Timing of initial symptom onset during milk and wheat challenges: A retrospective study

BACKGROUND

Allergic reactions to milk appear sooner than those to hen's eggs, irrespective of the total dose of the oral food challenges (OFCs) and type of matrices. The reported median times for the first symptom occurrence are 20-30 min with milk and 50-60 min with eggs. However, allergic reactions due to wheat have not yet been fully investigated.

METHODS

This study retrospectively collected data from OFC for milk and wheat conducted at Sagamihara National Hospital and Sendai Medical Center from 2009 to 2023. The time from the start of the OFC to the onset of symptoms was compared between children with cow's milk and wheat allergy.

RESULTS

Twenty-five and 13 children reacted to single-dose OFCs with milk products equivalent to 25 mL of raw cow's milk or 15 g of udon noodles, respectively. The median ages of patients with positive challenges were 1.4 and 2.8 years for milk and wheat, respectively, and the median times for the first symptom occurrence were 20 min and 53 min, respectively (p = .006).

CONCLUSION

This multicenter study was the first to examine the time of symptom appearance during single-medium-dose milk and wheat challenges. Allergic reactions to wheat appear later than those for milk during OFC. For multiadministration OFC for wheat, the dosing interval should be longer than 60 min. Our findings can help improve the safety of OFCs.

Allergic reactions to milk appear sooner than reactions to hen's eggs: a retrospective study

BACKGROUND

Oral food challenge test doses are recommended to be performed at least 20 min apart; however, the times of symptom provocation from the start of the oral food challenge have never been compared between different foods. In this study, the durations from the start of the oral food challenge to symptom development in children with egg or milk allergy were compared.

METHODS

Thirty-eight and 74 children who had previously passed oral food challenges to 96 g of yogurt and pumpkin cake containing ¼ whole egg underwent oral food challenges with 200 mL raw cow's milk and 1 whole scrambled egg, respectively; of these, 15/38 and 33/74 children had a reaction.

RESULTS

The median ages of patients with a positive challenge were 5.8 and 5.1 years for milk and eggs, respectively. The median times for the first symptom occurrence were 20 min (range, 5-55 min) and 50 min (5-480 min), respectively (p = 0.009). The first symptoms developed within 30, 60, and 90 min in 12/15 (80 %), 15/15 (100 %), and 15/15 (100 %) children with milk allergies, and in 10/33 (30.3 %), 20/33 (60.6 %), and 26/33 (78.8 %) children with egg allergies, respectively. The median times of peak symptoms were 50 min (10-210 min) and 120 min (30-560 min) (p = 0.001), and those of symptom disappearance were 90 min (30-240 min) and 180 min (80-700 min) for milk and eggs (p = 0.002), respectively.

DISCUSSION

Based on the results of our study, symptoms developed within 30 min for only a subset of patients for eggs, and may even take upwards of 60 min to develop. The times of symptom disappearance were 90 min and 180 min for milk and eggs, respectively, indicating that egg-allergic patients should be observed for a longer period time than milk-allergic patients.

CONCLUSIONS

Allergic reactions induced by milk appeared and disappeared sooner than those induced by eggs.

Erratum: Butter Tolerance in Children Allergic to Cow's Milk

[This corrects the article DOI: 10.4168/aair.2015.7.2.186.].

Butter Tolerance in Children Allergic to Cow's Milk

We performed an oral food challenge (OFC) with 10 g of butter (equivalent of 2.9 mL cow's milk) and 25-mL heated cow's milk for 68 children with cow's milk-allergy. Thirty-eight children reacted only to heated cow's milk. Twenty-four children reacted to neither heated milk nor butter. Thirty-eight (86.4%) of 44 patients with positive results to the OFC for heated milk could safely tolerate butter. It is highly likely that even children with cow's milk-allergy who show positive results to an OFC for heated milk can consume butter. The milk-specific IgE value indicative of a negative predictive value of over 95% was 17.8 kUA/L, and patients with low milk-specific IgE values may be able to safely consume butter. Including butter in the diets of patients with milk-allergy after a butter challenge may improve quality of life.

[The effects of great East Japan earthquake on patients with food allergy in Miyagi Prefecture]

BACKGROUND

Although many food-allergic children experienced the Great East Japan Earthquake, little was known about the effects of the disaster on them.

METHODS

Using a questionnaire survey, we studied 194 patients with food allergy in Miyagi Prefecture, who were hospitalized for the oral food challenge test after the earthquake. This survey consists of items related to the damage to home, means of gathering information, lack of allergen-free foods, exacerbation of atopic dermatitis or bronchial asthma, etc.

RESULTS

At the earthquake, most of the patients lived around Sendai city. Lifeline disruptions, communication breakdown, and goods shortage occurred in almost all family. Immediately after the earthquake, it was difficult to continue the food elimination diet. Asthmatic attack occurred in 14% of food-allergic children with bronchial asthma. Exacerbation of eczema was seen in 60% of food-allergic patients with atopic dermatitis. Almost all guardians of atopic dermatitis children think that it was because the shower was unavailable after the earthquake.

CONCLUSION

It is necessary to supply food-allergic patients with the specific food elimination diet, and atopic dermatitis patients with the shower facilities as soon as possible after the natural disaster occurs.

Non-Helicobacter bacterial flora rarely develops in the gastric mucosal layer of children

Non-Helicobacter bacteria can be cultured from the gastric mucosa in adults but in children, there are no studies about such microflora. The purpose of this study, therefore, was to clarify whether gastric biota develops in children. In 10 children and 10 adults or elderly (5 H. pylori-infected and 5 uninfected in each group), biopsy specimens of the gastric antrum and corpus and gastric juice were studied for bacterial examinations and the data were compared between both age groups in relation to H. pylori status and luminal pH. Bacterial genera and species were analyzed using both culture and real-time polymerase chain reaction (PCR) with the 52 genus- and species-specific primer sets. Non-Helicobacter bacteria in the mucosa were cultured from all adult patients, whereas microorganisms were cultured in only one child (p < .001). Gastric pH was lower in children (median, 1.4) than in adults (median, 2.6) (p < .005). The grade of endoscopic gastric atrophy was moderate or severe in 8 adults, but absent or mild in all 10 children. Among adults, there was a significant positive correlation between gastric pH and total bacterial counts of both the mucosa and juice. These data indicate that impaired gastric acid secretion associated with long-term H. pylori infection enables non-Helicobacter bacteria to colonize in the human stomach. Such microorganisms rarely colonize in the gastric mucosa in children regardless of H. pylori status.

Association between gastric atrophy and Helicobacter pylori infection in Japanese children: a retrospective multicenter study

The purpose of this study was to determine whether Helicobacter pylori infection and mucosal inflammation result in gastric atrophy in Japanese children. A total of 196 patients ages 1-16 years were retrospectively studied: 131 patients were infected with H. pylori and 65 patients were uninfected. Antral (n = 196) and corpus biopsy specimens (n = 70) were investigated based on the Updated Sydney system. In both the antrum and corpus, H. pylori-infected patients showed significantly higher degrees of inflammation and activity of gastritis, compared with noninfected patients. The prevalence of grade 2 or 3 atrophy in the antrum was 10.7% in H. pylori-infected patients and 0% in the noninfected patients (P < .01) and in corpus 4.3% and 0%, respectively (P = .20). The frequency of intestinal metaplasia in the 2 study groups was 4.6% and 4.6% in the antrum and 0% and 4.2% in the corpus, respectively. Among H. pylori-infected patients, the antrum showed significantly higher degrees of H. pylori density, inflammation and activity of gastritis, and atrophy than the corpus. In the antrum, atrophy was significantly correlated with activity, whereas in the corpus, atrophy correlated with H. pylori density, inflammation, and activity. H. pylori-induced gastric inflammation can cause atrophy in Japanese children, predominantly in the antrum. It remains to be determined whether H. pylori-infected children with gastric atrophy are at increased risk for gastric cancer.

Influence of age and duration of infection on bacterial load and immune responses to Helicobacter pylori infection in a murine model

Using a murine model, we previously showed that Helicobacter pylori infects and colonizes offspring via maternal transmission during the nursing period. The aim of this study was to investigate the influence of age and duration of infection on inflammatory and immune responses to H. pylori in infant and adult mice. During the breast-feeding period, the number of bacteria was significantly suppressed in 1-week-old mice infected with H. pylori at an early stage of nursing, compared with adult mice, suggesting that breast-milk induces such low colonization. In addition, these mice had weaker gastric inflammation, especially Th1 cytokine and humoral responses than in mice infected with H. pylori after weaning in spite of elevated levels of Th1 cytokines. Although infant mice showed low inflammatory responses against H. pylori, they produced H. pylori-specific antibodies following vaccination with oral or parenteral adjuvant. Our results suggest the importance of age at the time of primary infection on bacterial load, gastric inflammation and humoral responses in a murine model of H. pylori infection.

Gastric epithelial cell turnover and mucosal protection in Japanese children with Helicobacter pylori infection

BACKGROUND

In adults, epithelial cell proliferation and apoptosis of the gastric mucosa are induced by Helicobacter pylori infection and are associated with gastric atrophy or gastric carcinoma. In children, there are few studies about such epithelial changes. To elucidate the role of H. pylori infection in gastric mucosal inflammation, we immunohistochemically examined gastric mucosa of Japanese children.

METHODS

Biopsy specimens obtained from the gastric antrum and corpus of H. pylori-infected (n = 13) and noninfected children (n = 15) were studied for immunolocalization of Ki-67, single-strand DNA, manganese superoxide dismutase (Mn-SOD), and CD68, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling. In 10 patients with successful eradication, pre- and posttreatment results were compared.

RESULTS

In both gastric antrum and corpus, neutrophil and mononuclear cell infiltration, epithelial cell proliferation, and apoptosis significantly increased in H. pylori-infected patients, predominantly in the antrum. In the antrum of H. pylori-infected patients, there was positive correlation between the degrees of neutrophil infiltration and cell proliferation (P < 0.05) or apoptosis (P < 0.05). H. pylori eradication improved mucosal inflammation, cell proliferation (P < 0.001), and apoptosis (P < 0.01) in the antrum. Mn-SOD immunoreactivity and CD68-positive macrophages in the antrum, which significantly increased in H. pylori-infected patients, decreased after the eradication.

CONCLUSIONS

H. pylori infection induced gastric mucosal inflammation and epithelial cell turnover in children. Moreover, gastric mucosal defense mechanism against H. pylori infection was activated. H. pylori eradication in childhood might prevent the accumulation of gastric epithelial cell damage.

Helicobacter heilmannii infection in a child after successful eradication of Helicobacter pylori: case report and review of literature

An 11-year-old boy with Helicobacter pylori-associated duodenal ulcer was successfully treated with a combination of lansoprazole, amoxicillin, and clarithromycin. Endoscopy and gastric biopsies were repeated 2 and 12 months later, showing ulcer healing and eradication of H. pylori. However, a 3-year follow-up study demonstrated H. heilmannii in the antral mucosa based on its characteristic morphology and positive urease test and negative culture. The patient had no contact with domestic animals such as cats and dogs. A 7-day course with lansoprazole, amoxicillin, and clarithromycin was performed again, resulting in successful eradication of the organism. Pediatric cases with H. heilmannii infection reported are reviewed.

Multicenter comparison of rapid lateral flow stool antigen immunoassay and stool antigen enzyme immunoassay for the diagnosis of Helicobacter pylori infection in children

BACKGROUND AND AIM

The stool antigen enzyme immunoassay (EIA) methods are widely used for diagnosing Helicobacter pylori infection. Recently, a novel, rapid stool antigen test, the lateral flow immunoassay (LFI) method, has been developed. The primary purpose of this study was to compare the EIA method with the LFI method for the diagnosis of H. pylori infection in children.

MATERIALS AND METHODS

Stool specimens from children being evaluated for H. pylori infection were also examined using the LFI (ImmunoCard STAT! HpSA) and EIA methods (Premier Platinum HpSA). The sensitivity, specificity and accuracy of the test were based on the 13C-labeled urea breath test.

RESULTS

One hundred and eighty-two children and adolescents, 3-17 years of age (mean 9.2 years), were studied. In addition, 29 patients who received eradication therapy were re-evaluated 2 or 3 months post-treatment. The 13C-labeled urea breath test was positive in 64 patients (35.2%). The sensitivity, specificity and accuracy of the LFI method were 90.6% (95% CI = 80.7-96.5%), 95.8% (92.1-99.4%), and 94.0% (90.5-97.4%), respectively and for the EIA method, sensitivity, specificity and accuracy were 96.8% (95% CI, 89.0-99.6%) and 99.2% (97.5-100%), and 98.3% (96.5-100%), respectively. There were no significant differences in results among the age groups 3-5, 6-10 and 11-17 years. As for the assessment of H. pylori eradication, the results of the LFI and EIA methods agreed with those of 13C-urea breath test in 27/29 and 29/29 patients, respectively.

CONCLUSIONS

The LFI stool antigen method showed a good sensitivity, specificity and accuracy for diagnosing H. pylori infection in children. This novel method may be useful in clinical practice as an office-based test because it is rapid, reliable and easy to perform.

Comparison between the 13C-urea breath test and stool antigen test for the diagnosis of childhood Helicobacter pylori infection

BACKGROUND

As noninvasive tests for Helicobacter pylori infection, the 13C-urea breath test (UBT) and stool antigen test have been widely used. In children, however, there are few studies reporting which test shows superior performance. The purpose of this study was to compare the 13C-UBT and stool antigen test for their accuracy in diagnosing H. pylori infection in children.

METHODS

A total of 123 Japanese children, ages 2 to 17 years (mean, 12 years) who underwent gastric biopsies for H. pylori infection were studied. The diagnoses included gastritis (n = 55), gastric ulcer (n = 5), duodenal ulcer (n = 20), iron-deficiency anemia (n = 7), and other conditions (n = 36). The cutoff value of the 13C-UBT was defined to be 3.5 per thousand. The stool antigen test was performed using the HpSA enzyme-linked immunosorbent assay (ELISA) (Premier Platinum HpSA). In 16 patients who received eradication therapy, the 13C-UBT and HpSA were repeated 2 months after treatment.

RESULTS

Based on biopsy tests, 60 children were infected with H. pylori and 63 children were not. For the 13C-UBT, the sensitivity, specificity, and accuracy were 95.0% (95% confidence interval [CI], 86.1%-99.0%), 98.4% (95% CI, 91.5%-100%), and 96.4% (95% CI, 93.6%-99.9%), respectively. For the HpSA, the sensitivity, specificity, and accuracy were 98.3% (95% CI, 90.8%-100%), 98.4% (95% CI, 91.2%-100%), and 98.3% (95% CI, 96.0%-100%), respectively. There were no significant differences between the performance of these two tests. In the assessment of H. pylori eradication, the results of 13C-UBT and HpSA agreed with those of biopsy tests.

CONCLUSIONS

The 13C-UBT and the HpSA are equally accurate for the diagnosis of active H. pylori infection in Japanese children.

Diversity of vacA and cagA genes of Helicobacter pylori in Japanese children

BACKGROUND

Helicobacter pylori infection is generally acquired in childhood and persists as an asymptomatic infection for decades in most infected individuals. Only a minority develops a clinical outcome even in childhood, such as peptic ulcer. It has been reported that H. pylori infection with the type I strain, which expresses the VacA and CagA antigen, is associated with peptic ulcer.

AIM

We examined the diversity of vacA and cagA genes in isolates obtained from Japanese paediatric patients with peptic ulcer or chronic gastritis to investigate the relationship between genetic diversity and clinical outcome.

METHODS

The diversity of vacA and cagA genes was investigated by PCR and sequence analysis in 30 isolates obtained from Japanese paediatric patients with peptic ulcer (eight strains) or chronic gastritis (22 strains).

RESULTS

All isolates from Japanese children were cagA-positive strains. Twenty-six strains (86.7%) had East Asian type CagA, and 4 (13.3%) had Western type CagA. The predominant vacA genotype was s1c/m1b (22/30, 73.3%). There was no significant association between the diversity of cagA and vacA genes and clinical outcome. All four children infected with Western CagA strain had a history of overseas travel or residence.

CONCLUSION

The predominant genotype of H. pylori in Japanese children is East Asian CagA and vacA s1c/m1b genotype, regardless of clinical outcome. Japanese H. pylori strains are homogeneously of the East Asian type; however, Western strains can be introduced into Japan concomitant with host movement from foreign countries in childhood.

Effect of Helicobacter pylori infection on gastric acid secretion and meal-stimulated serum gastrin in children

BACKGROUND

Comparative studies of gastric acid secretion in children related to Helicobacter pylori infection are lacking. The purpose of this study was to compare acid secretion and meal-stimulated gastrin in relation to H. pylori infection among pediatric patients.

MATERIALS AND METHODS

Thirty-six children aged 10-17 years (17 with H. pylori infection) undergoing diagnostic endoscopy participated in the study. Diagnoses included gastritis only (n = 23), duodenal ulcer (n = 5) and normal histology (n = 8). Gastric acid output was studied using the endoscopic gastric secretion test before and 2-3 months after H. pylori eradication. Meal-stimulated serum gastrin response was assessed before and 12 months after eradication.

RESULTS

H. pylori gastritis was typically antrum-predominant. Acid secretion was greater in H. pylori-positive patients with duodenal ulcer than in gastritis-only patients or controls [mean +/- standard error (SE): 6.56 +/- 1.4, 3.11 +/- 0.4 and 2.65 +/- 0.2 mEq/10 minutes, respectively; p <.001]. Stimulated acid secretion was higher in H. pylori-positive boys than girls (5.0 +/- 0.8 vs. 2.51 +/- 0.4 mEq/10 minutes, respectively; p <.05). Stimulated acid secretion pre- and post-H. pylori eradication was similar (5.47 +/- 0.8 vs. 4.67 +/- 0.9 mEq/10 minutes, respectively; p =.21). Increased basal and meal-stimulated gastrin release reversed following H. pylori eradication (e.g. basal from 134 to 46 pg/ml, p <.001 and peak from 544 to 133 pg/ml, p <.05).

CONCLUSIONS

H. pylori infection in children is associated with a marked but reversible increase in meal-stimulated serum gastrin release. Gastric acid hypersecretion in duodenal ulcer remains after H. pylori eradication, suggesting that the host factor plays a critical role in outcome of the infection.

Childhood Helicobacter pylori infection in a murine model: maternal transmission and eradication by systemic immunization using bacterial antigen-aluminium hydroxide

In humans, transmission of Helicobacter pylori is thought to occur largely during childhood. Infected mothers are generally considered to be the main source of the pathogen. However, little is known about when and how often maternal transmission of H. pylori occurs during childhood. In the present study, we examined these issues in an experimental murine model. Pregnant C57BL/6 mice, infected experimentally with H. pylori, delivered and nursed their litters. The stomachs of the infants were isolated and assessed for transmission of H. pylori. We also investigated the effect of systemic immunization using H. pylori antigen-aluminium hydroxide (AlOH) with regard to providing anti-H. pylori immunity and eradicating the maternally transmitted bacteria in infants. Polymerase chain reaction (PCR) was used to examine the presence of transmitted bacteria and their eradication. Maternal transmission of H. pylori varied widely during the nursing period, but almost all litters showed bacterial transmission at 2 weeks postpartum. Systemic immunization with bacterial antigen-AlOH eradicated the bacteria in most litters; this immunization induced a local decrease of Th2 cytokines and a local increase of Th1 cytokines in the gastric tissue, as determined by ELISA. Our results indicate that our H. pylori vaccine provides not only protection, but also eradication of the already transmitted H. pylori.

Evaluation of therapeutic efficacy of adjuvant Helicobacter pylori whole cell sonicate in mice with chronic H. pylori infection

Successful prophylactic administration of Helicobacter pylori whole cell sonicate (WCS) plus complete Freund's adjuvant (CFA) or aluminum hydroxide (ALM) against subsequent H. pylori infection was reported recently. Here we tested the effect of WCS plus TiterMax Gold (TMX) or ALM in mice with chronic H. pylori infection. Mice with chronic (18 weeks) H. pylori infection were injected intraperitoneally with H. pylori (Sydney strain) WCS plus ALM or TMX once weekly for three times. The number of colonizing H. pylori in the stomach, IgG1 and IgG2a levels, and local inflammatory status were determined after therapeutic immunization. H. pylori specific IgG1, but not IgG2a, was significantly induced in mice immunized with H. pylori WCS plus TMX or ALM. Immunization did not result in reduction of bacterial count or recruiting inflammatory cells to the stomach. Adjuvant H. pylori WCS resulted in induction of CD4+ Th2 cell-mediated immunity although it did not reduce bacterial density in mice with chronic H. pylori infection. Our results implied that CD4+ Th1 cell-mediated immunity, rather than Th2 cell dominant immunity, might play a role in reducing the number of bacteria in chronic H. pylori infection.

[The prospects of vaccination against H. pylori infection]

H. pylori causes numerous gastroduodenal diseases including malignancies. Although eradication of H. pylori using antibiotics is clinically performed, it is sometimes unsuccessful because of resistant bacteria and patient non-compliance with treatment. Therefore prophylactic and therapeutic vaccination against H. pylori infection is necessary for clinical use but it is still under study. H. pylori is widely believed to be transmitted in childhood. If long and chronic H. pylori infection causes gastric cancer, vaccination should be targeted at children for the prophylaxis of cancer. Systemic immunization with aluminum hydroxide which has been already proved to be safe for human child, deserve attention.

Diagnostic accuracy of the 13C-urea breath test for childhood Helicobacter pylori infection: a multicenter Japanese study

OBJECTIVES

In adults, the 13C-urea breath test (UBT) has been widely used as a noninvasive test of Helicobacter pylori infection because of its high sensitivity and specificity. However, this test is less well established in pediatric practice. The optimum cutoff value and test protocol of the 13C-UBT remains to be established in the pediatric population. The primary purpose of this study was to evaluate diagnostic accuracy of the 13C-UBT for children and to determine its optimum cutoff value.

METHODS

A total of 220 Japanese children aged 2-16 yr (mean = 11.9) who underwent upper GI endoscopy and gastric biopsies were finally studied. Endoscopic diagnoses included gastritis (n = 131), gastric ulcer (n = 15), duodenal ulcer (n = 72), and combined ulcer (n = 2). H. pylori infection status was confirmed by biopsy tests including histology, urease test, and culture. With the 13C-UBT, breath samples were obtained at baseline and at 20 min after ingestion of 13C-urea without a test meal and were analyzed by isotope ratio mass spectrometry. Based on biopsy tests, a cutoff value was determined using a receiver operating characteristic curve. In 26 children (seven children infected and 19 noninfected), paired breath samples were also measured by nondispersive infrared spectometry (NDIRS).

RESULTS

Biopsy tests demonstrated that 89 children (40%) were infected with H. pylori and 131 children were not infected. There were no statistical differences in mean delta 13C values at 20 min between male and female H. pylori-infected and noninfected patients. A receiver operating characteristic analysis defined the best cutoff value as 3.5 per thousand. The overall sensitivity and specificity at a cutoff value of 3.5 per thousand were 97.8% (95% CI = 92.1-99.7%) and 98.5% (95% CI = 96.4-100%), respectively: high sensitivity and specificity were demonstrated in all three age groups (< or =5, 6-10, and > or = 11 yr). There was a close correlation between the values with isotope ratio mass spectrometry and NDIRS methods (r = 0.998, p < 0.001).

CONCLUSIONS

The 13C-UBT with a cutoff value of 3.5 per thousand is an accurate diagnostic method for active H. pylori infection. The test with the NDIRS method is inexpensive and might be widely applied in clinical practice.

Diagnostic accuracy of the 13C-urea breath test for childhood Helicobacter pylori infection: a multicenter Japanese study

OBJECTIVES

In adults, the 13C-urea breath test (UBT) has been widely used as a noninvasive test of Helicobacter pylori infection because of its high sensitivity and specificity. However, this test is less well established in pediatric practice. The optimum cutoff value and test protocol of the 13C-UBT remains to be established in the pediatric population. The primary purpose of this study was to evaluate diagnostic accuracy of the 13C-UBT for children and to determine its optimum cutoff value.

METHODS

A total of 220 Japanese children aged 2-16 yr (mean = 11.9) who underwent upper GI endoscopy and gastric biopsies were finally studied. Endoscopic diagnoses included gastritis (n = 131), gastric ulcer (n = 15), duodenal ulcer (n = 72), and combined ulcer (n = 2). H. pylori infection status was confirmed by biopsy tests including histology, urease test, and culture. With the 13C-UBT, breath samples were obtained at baseline and at 20 min after ingestion of 13C-urea without a test meal and were analyzed by isotope ratio mass spectrometry. Based on biopsy tests, a cutoff value was determined using a receiver operating characteristic curve. In 26 children (seven children infected and 19 noninfected), paired breath samples were also measured by nondispersive infrared spectometry (NDIRS).

RESULTS

Biopsy tests demonstrated that 89 children (40%) were infected with H. pylori and 131 children were not infected. There were no statistical differences in mean delta 13C values at 20 min between male and female H. pylori-infected and noninfected patients. A receiver operating characteristic analysis defined the best cutoff value as 3.5 per thousand. The overall sensitivity and specificity at a cutoff value of 3.5 per thousand were 97.8% (95% CI = 92.1-99.7%) and 98.5% (95% CI = 96.4-100%), respectively: high sensitivity and specificity were demonstrated in all three age groups (< or =5, 6-10, and > or = 11 yr). There was a close correlation between the values with isotope ratio mass spectrometry and NDIRS methods (r = 0.998, p < 0.001).

CONCLUSIONS

The 13C-UBT with a cutoff value of 3.5 per thousand is an accurate diagnostic method for active H. pylori infection. The test with the NDIRS method is inexpensive and might be widely applied in clinical practice.

A computer simulation study of isometric contraction of latissimus dorsi muscle used for cardiac assistance

This study was designed to investigate the feasibility of a skeletal muscle pump employing latissimus dorsi muscle (LDM) for cardiac assistance. We developed and used a 2-dimensional mathematical model for LDM to investigate how the size of pneumatic balloons (30, 38, and 45 ml) and the three different locations (proximal, center, and distal) affect the pressure applied to the balloon by LDM. The computer simulation was performed by coding a visco-elastic and nonlinear 2-dimensional program that employed the finite element method (FEM). The muscle specific parameters of LDM were obtained from animal experiment results. The model is based on Hill's characteristic equation and composed of a contractile component and a passive element. The simulation results indicated that the intermediate and largest sized balloon lead to the highest and the lowest power (volume reduction per unit time interval), respectively. On the other hand, when the balloon is inserted in the distal LDM, the power is lower than in the other two positions, regardless of the balloon size. The above results suggest that the optimal size of the balloon should be selected depending on the muscle specific parameters of the actuator, and that the balloon should be inserted either in the proximal portion or center of the actuator.

Effect of hepatocyte volume on energy status in the cirrhotic rat liver

To evaluate the effect of reduced hepatocyte volume on liver energy status, the relationship between the morphologically quantified hepatocyte volume and biochemical parameters, and the difference in nuclear density between the parenchyma and stroma were assessed in rat livers with thioacetamide-induced cirrhosis. The ratio of hepatocytes to whole liver tissue, defined as the 'hepatocyte area ratio', and the nuclear densities of the parenchyma and stroma were calculated microscopically with an image analysing system. Adenine nucleotide, protein and DNA contents, and the ornithine carbamoyltransferase activity in the liver were assayed. In the cirrhotic group, adenine nucleotide content, protein content and ornithine carbamoyltransferase activity were positively correlated with the hepatocyte area ratio, whereas DNA content was negatively correlated with this ratio. The adenylate energy charge of the cirrhotic liver was maintained at a constant level regardless of the ratio. Adenine nucleotide content, protein content and ornithine carbamoyltransferase activity per fractional 'hepatocyte area ratio' in cirrhotic livers were significantly lower than in control livers. The nuclear density of the stroma was significantly greater than that of the parenchyma. These results suggest that the lowered energy status in the cirrhotic liver is not caused by reduced hepatocyte volume but rather by impaired hepatocyte metabolism. In addition, the morphological measurement with an image analysing system was found to be useful for evaluating the effects of decreased hepatocyte volume on biochemical derangements in cirrhotic tissue.

[Coagulation and fibrinolysis in pregnancy]

We studied on coagulation and fibrinolysis systems during pregnancy by measuring plasma levels of thrombin-antithrombin III complex (TAT), plasmin-alpha 2 plasmin inhibitor complex (PIC), fibrinogen/fibrin degradation products (FDP), plasminogen (PLG) and antithrombin III (AT-III). Ninety seven pregnant, 5 post-delivery and 32 nonpregnant women aged from 20 to 52 years old were included in this study. Plasma concentrations of TAT and PIC in nonpregnant women were 3.38 +/- 1.02 micrograms/l and 0.65 +/- 0.24 micrograms/ml, respectively. TAT gradually increased with the progression of pregnancy and rapidly decreased after the delivery. Whereas PIC and AT-III concentrations did not change significantly during pregnancy. Fibrinogen, PLG and FDP concentrations changed similarly as TAT. Eight pregnants whose plasma PIC concentrations elevated more than 1.0 micrograms/l were further examined. In 6 women out of them (71.5%), FDP concentrations were elevated. In this particular group of subjects, however, they delivered normally without complications such as toxemia. These observations suggest that, at least, a hypercoagulative state progresses with pregnancy, being normalized after the delivery. Although we could not find the relationship between the hypercoagulation and clinical complications such as thrombosis and toxemia of pregnancy, present findings suggest that special caution should be paid on the pregnants whose TAT and FDP levels are elevated.

Comparability of hamster with human faecal unconjugated bile acids in a model of colorectal cancer

The relationship between experimental colorectal carcinogenesis and bile acids has usually been investigated in the rat, a species with a markedly different bile acid profile from man. In this study, we show that the hamster faecal bile acid profile is similar to that in man. Rectal cancer was induced in hamsters using twice weekly instillations of N-methyl-N-nitro-N-nitrosoguanidine (MNNG) for 4 weeks at doses of 1-8 mg kg-1. The medcian (range) faecal bile acid concentrations of tumour-bearing hamsters (0.52, 0.46-0.84 mumoles g-1 faeces) was reduced compared to controls (1.08, 0.95-1.65, mumoles g-1) and non-tumour bearing MNNG treated hamsters (1.18, 0.64-1.42 mumoles g-1), largely due to a decrease in cholic acid derivatives (all p less than 0.05) at least). This model may be more suitable for studying the relationship between colorectal cancer and bile acids.

[Anticoagulants preventing pseudo-thrombocytopenia]

It is well known that some anticoagulants, especially EDTA (ethylene diamine tetraacetic acid), sometimes lead to pseudo-thrombocytopenia due to the aggregation of thrombocytes. We evaluated appropriate anticoagulants that prevent pseudo-thrombocytopenia without affecting other hematological data. In this study, 10 mg EDTA-2K and 1 mg citric acid were added to 1 ml of blood as anticoagulants. Using these anticoagulants (EC method), an aggregation of thrombocytes was clearly inhibited and the platelet counts remained stable in 10 cases with pseudo-thrombocytopenia. This method did not affect the other blood cell counts, the stainability and the morphology of the cells. Since the addition of citric acid to EDTA could prevent the cell volume change induced by the high concentration of EDTA, the micro-hematocrit values were remained unchanged. Hematological data in 20 cases which did not show any pseudo-thrombocytopenia, correlated significantly between the EDTA method and the EC method, and did not change significantly 24 hours after blood sampling. It is concluded that EDTA and citric acid may be a useful combination of anticoagulants for the prevention of pseudo-thrombocytopenia.

Specific inhibitory effect of dietary eicosapentaenoic acid on N-nitroso-N-methylurea-induced mammary carcinogenesis in female Sprague-Dawley rats

We have investigated the effects of two qualitatively different types of unsaturated fatty acids on N-nitroso-N-methylurea (NMU)-induced mammary carcinogenesis in female Sprague-Dawley rats. Semipurified diets containing 4.7% eicosapentaenoic acid (EPA) plus 0.3% linoleic acid or 5% linoleic acid were prepared. Animals maintained on these diets were given an i.v. injection of NMU (50 mg/kg body wt) at 50 days of age and killed 20 weeks later. Both tumor incidence and tumor number per rat were significantly lower in the EPA diet group (60.0% and 2.3 +/- 2.5 versus 93.3% and 5.1 +/- 4.5 respectively) for the 5% linoleic acid diet. Furthermore, the average weight of tumor material (total) per rat was significantly lower in the EPA as compared to linoleic acid diet group (2.9 +/- 4.2 g and 11.4 +/- 12.2 g respectively). Analysis of phospholipid fatty acids in the mammary tumors in the EPA diet group showed a higher proportion of C16:0, C18:2, omega-3 fatty acids C20:5 and C22:6 and a lower proportion of C20:4. Furthermore, mammary tumors in rats fed the EPA diet demonstrated significant reduction in prostaglandins. The results thus suggest that inhibition by EPA of NMU-induced mammary carcinogenesis may be mediated via the modulation of lipid metabolism and associated reduction in prostaglandin synthesis.

[A double cancer of the gallbladder and common bile duct associated with an anomalous arrangement of the choledocho-pancreatic ductal junction--a case report and a review of the literature]

Reported is the case of a 65-year-old woman who complained of general fatigue and itching. The cancer of the gallbladder and the common bile duct associated with anomalous arrangement of choledocho-pancreatic ductal junction was diagnosed after examination by ERCP, PTCS, US, and CT. The cancer of the common bile duct had metastasized to the pancreas, the portal vein, and the regional lymph nodes and was unresectable. It is well known that an anomalous arrangement of the choledocho-pancreatic ductal junction is highly associated with a cancer of the common bile duct or the gallbladder. But a case that is associated with double cancers is rare and only 6 cases have been reported in the Japanese literature. In addition to a discussion of this case, the literature is reviewed.

Prognostic significance of serosal invasion and free intraperitoneal cancer cells in gastric cancer

Survival rates after curative gastrectomy for advanced gastric cancer among 238 patients in whom the cancer was invading the serosa were compared with 283 patients without serosal invasion. Generalized Wilcoxon estimates for 5-year survival rate were 47.1 per cent for patients exhibiting serosal invasion and 75.9 per cent for patients without serosal invasion. The frequency of lymph node metastasis increased proportionately with the extent of serosal invasion: 18.4 per cent in cases of S0; 53.8 per cent in cases of S1; 80.0 per cent in cases of S2; and 91.4 per cent in cases of S3. The higher the aggregate total of S (serosal invasion) and n (lymph node metastasis) factors, the lower the 5-year survival rate. In addition, patients with serosal invasion had a propensity for peritoneal dissemination of cancer cells; the percentage of cases with intraperitoneal free cancer cells increased with the extent of serosal invasion. It is worth noting that when cancer infiltration proceeded to the deeper layers and was accompanied by nodal metastasis, cancerous invasion of the perinodal fatty tissue was frequently evident. Therefore, unfavourable prognosis after curative resection in gastric cancer patients with serosal invasion may be largely dependent on whether or not the cancer has invaded the peritoneal cavity and the perinodal fatty tissue.

Effect of dietary eicosapentaenoic acid on azoxymethane-induced colon carcinogenesis in rats

The effects of eicosapentaenoic acid (EPA, n-3 polyunsaturated fatty acid) and linoleic acid (n-6 polyunsaturated fatty acid) on azoxymethane-induced colon carcinogenesis in rats were studied. Male Donryu rats were given two types of semipurified diet containing 4.7% EPA plus 0.3% linoleic acid and 5% linoleic acid. The rats were given s.c. injection of azoxymethane (7.4 mg/kg body weight once a week for 11 weeks) and sacrificed 15 weeks after the last injection of azoxymethane. The tumor incidence and tumor yields (tumors per rat) of the colon were significantly lower in rats on the EPA diet compared to those on the linoleic acid diet; i.e., 33%, 0.41 +/- 0.61 and 69%, 1.66 +/- 1.69, respectively. In the analysis of phospholipid fatty acid composition, the colon tumor showed higher levels of arachidonic acid and lower levels of linoleic acid than those in the normal colon mucosa in both diet groups. Despite the increase of arachidonic acid in colon tumor, the EPA diet suppressed the excessive production of prostaglandin E2, which may be accompanied with neoplastic formation, whereas linoleic acid diet caused a marked increase in the tumor content of prostaglandin E2 compared to normal colon mucosa. These results suggest that EPA exerts its inhibitory effect on colon carcinogenesis by modulating lipid metabolism and inhibiting prostaglandin E2 synthesis in tumor cells.

Effects of dietary saturated and unsaturated fatty acids on fecal bile acids and colon carcinogenesis induced by azoxymethane in rats

To determine whether the kind of dietary fat affects colon carcinogenesis, male Donryu rats were fed a 5% fat diet containing linoleate, an unsaturated fat, or stearate, a saturated fat, in semipurified fat-free chow. The rats were given azoxymethane (7.4 mg/kg body weight) s.c. once a week for 11 weeks and killed 15 weeks after the last injection of the carcinogen. The rats on the unsaturated fat diet had a significantly higher incidence of colon tumors. Fatty acid analysis of cholesterol esters in the liver and examination of the amount of fecal bile acids showed that the unsaturated fat diet increased the level of cholesterol linoleate and arachidonate in the liver and also increased the fecal excretion of bile acids, especially that of lithocholic acid. The colon tumors in rats on the unsaturated fat diet, compared with those in rats on the saturated fat diet, contained a higher level of lysophosphatidylcholine. These results suggest that increased fecal excretion of bile acids due to increased polyunsaturated cholesterol esters in the liver stimulates phospholipase A2 activity of colon initiated cells and enhances colon carcinogenesis in rats on the unsaturated fat diet.