A Multicenter Prospective Survey on Early-Onset Inflammatory Bowel Disease in Japan

INTRODUCTION

The incidence of early-onset inflammatory bowel disease is increasing in Japan.

OBJECTIVE

This study aimed to analyze the treatment and progress of early-onset inflammatory bowel disease.

METHODS

This prospective survey evaluated the data of 43 patients aged <8 years who were diagnosed with inflammatory bowel disease (IBD) from the time of diagnosis to 36 months after registration.

RESULTS

A total of 12 patients with Crohn's disease (CD), 21 with ulcerative colitis (UC), and 3 with unclassified IBD were enrolled. The mean disease onset age was 3 years and 7 months. Colon and anal lesions were present in 100 and 50% of patients with CD, respectively. Granulomas were detected in 5 patients (41.7%). Dietary elimination including elemental diet was performed in all patients. Eleven patients (91.7%) were in remission by initial induction therapy, and 72.7% maintained remission for 36 months. Three patients (14.3%) with UC had familial history, 71.4% had pancolitis-type UC, and 66.7% exhibited disease of moderate severity. Colectomy was performed in 4 patients (21.1%). Eighteen patients (85.7%) were in remission by initial induction therapy; however, only 15.8% maintained remission for 36 months. Anal complication was more prevalent in infantile-onset IBD than in childhood-onset IBD (p = 0.014).

CONCLUSIONS

Among Japanese patients aged <8 years who were diagnosed with IBD, colitis-type disease was more common in CD and pancolitis was more common in UC. As the courses of several patients were severe, identifying primary immunodeficiency appears to be necessary to confirm background disease.

Clinical, Pathologic, and Genetic Features of Neonatal Dubin-Johnson Syndrome: A Multicenter Study in Japan

OBJECTIVE

To clarify the clinical, pathologic, and genetic features of neonatal Dubin-Johnson syndrome.

STUDY DESIGN

Ten patients with neonatal Dubin-Johnson syndrome were recruited from 6 pediatric centers in Japan between September 2013 and October 2016. Clinical and laboratory course, macroscopic and microscopic liver findings, and molecular genetic findings concerning ATP-binding cassette subfamily C member 2 (ABCC2) were retrospectively and prospectively examined.

RESULTS

All neonates exhibited cholestasis, evident as prolonged jaundice with or without acholic stools and elevations of serum direct bilirubin as well as γ-glutamyltransferase or total bile acids. Only 38% (3 of 8) of patients who underwent liver biopsy showed a grossly black liver or melanin-like pigment deposits in hepatocytes; their biopsies were performed in early infancy. Immunohistochemically, all liver specimens showed no expression of multidrug resistance-associated protein 2 but increased expression of the bile salt export pump protein. Homozygous or compound heterozygous pathogenic variants of ABCC2 were identified in all patients, representing 11 distinct pathogenic variants including 2 not previously reported.

CONCLUSIONS

Immunohistochemical staining of the liver for multidrug resistance-associated protein 2 and molecular genetic analysis of ABCC2 are crucial for accurate diagnosis of neonatal Dubin-Johnson syndrome.

Screening of carnitine and biotin deficiencies on tandem mass spectrometry

BACKGROUND

It is important to assess pediatric patients for nutritional deficiency when they are receiving specific interventions, such as enteral feeding. We focused on measurement of C0 and 3-hydroxyisovalerylcarnitine (C5-OH) with tandem mass spectrometry (MS/MS), which is performed as part of the newborn mass screening. The purpose of this study was to investigate the usefulness of MS/MS for screening carnitine and biotin deficiencies.

METHODS

Forty-two children (24 boys, 18 girls) were enrolled between December 2013 and December 2015. Blood tests, including measurement of serum free carnitine via the enzyme cycling method, and acylcarnitine analysis on MS/MS of dried blood spot (DBS), were performed for the evaluation of nutrition status.

RESULTS

Median patient age was 2 years (range, 2 months-14 years). Mean serum free carnitine was 41.8 ± 19.2 μmol/L. In six of the 42 patients, serum free carnitine was <20 μmol/L (range, 4.0-18.7 μmol/L). C0 and C5-OH measured on MS/MS of DBS were 33.8 ± 20.2 nmol/mL and 0.48 ± 0.22 nmol/mL, respectively. There was a strong positive correlation (r = 0.89, P < 0.001) between serum free carnitine and C0 measured on the same day. In one patient on hydrolyzed formula, C5-OH was >1.00 nmol/L. Therapy-resistant eczema was improved by treatment with additional biotin and a non-hydrolyzed formula.

CONCLUSION

C0 and C5-OH, measured on MS/MS of DBS, were useful for screening carnitine and biotin deficiencies.

Difference between early onset and late-onset pediatric ulcerative colitis

BACKGROUND

Early onset pediatric ulcerative colitis (EO-UC) is distinguished from late-onset pediatric ulcerative colitis (LO-UC) by the effects of genetic predisposition, but there have been few reports on the clinical features of EO-UC in Asia.

METHODS

To describe and compare the presentation and disease course of EO-UC (age range, 0-7 years) with those of LO-UC (age range, 8-15 years), we retrospectively analyzed 63 children with UC who had been diagnosed between January 2004 and March 2014 at Saitama Children's Medical Center in Japan.

RESULTS

Ten patients (16%) had EO-UC, and 53 (84%) had LO-UC. All patients in the EO-UC group and 70% in the LO-UC group had pancolitis (P = 0.05). The period from onset to diagnosis was 9.0 ± 14.1 months for EO-UC and 2.6 ± 3.5 months for LO-UC (P < 0.01). The prevalence of extra-intestinal complications at diagnosis was significantly higher for EO-UC than for LO-UC (50% vs 11%, respectively; P < 0.01). There were no significant differences in the use of corticosteroids, immunomodulators, immunosuppressants, or surgical risk between the groups but, in the EO-UC group, only one patient was treated with cytapheresis and none was treated with anti-tumor necrosis factor (TNF-α) antibodies.

CONCLUSIONS

The EO-UC group had a higher incidence of pancolitis, longer diagnostic delay, and more extra-intestinal manifestations than the LO-UC group. Diagnosis and treatment may therefore be slightly more difficult for EO-UC than for LO-UC.

Characteristics of inflammatory bowel disease with an onset before eight years of age: a multicenter epidemiological survey in Japan

BACKGROUND AND AIM

Pediatric inflammatory bowel disease (IBD) has not been rare in Japan since the 1990s. The present study attempted to define the epidemiological and clinical characteristics of early-childhood IBD in Japan in comparison with results from Western countries.

METHODS

Among children diagnosed as having IBD between January 1998 and December 2008, those showing onset before 8 years of age were investigated retrospectively. A questionnaire survey was carried out at 45 facilities throughout Japan, and 80 cases were reported from 27 facilities. On the basis of the final diagnosis, 24 patients with Crohn's disease (CD) and 47 patients with ulcerative colitis (UC) were analyzed.

RESULTS

Among the patients with CD, the age at onset was less than 1 year in 62.5%. On the basis of the Montreal classification, 87.5% of CD cases involved the colon, and 63.8% of UC cases were pancolitis. Coexisting conditions such as congenital diseases (five cases) and cerebral palsy (four cases) were present before the onset of IBD. Growth failure was more severe (P < 0.05) at diagnosis in CD patients than in UC patients. Familial occurrence within first-degree relatives was observed in eight families among 45 patients with UC, compared with none among the CD patients (P < 0.05).

CONCLUSION

Our results suggest that, in Japan, the pathogenesis of IBD in infants and children may differ from that in Western countries, and that the characteristics of early childhood-onset IBD are distinct from those of school age-onset IBD.

Successful colonoscopic approach in a child with intussusception associated with enterohemorrhagic Escherichia coli O157 infection

The pathogenesis of intussusception caused by enterohemorrhagic Escherichia coli (E. coli) O157 infection is unknown. In our case, colonoscopy was useful for confirming O157 infection. The intussusception was caused by focally damaged edematous mucosa in the cecum. This case helped in elucidating the pathogenesis of the disease.

[Severe aplastic anemia following living-donor liver transplantation for fluminant hepatitis]

We report a case of a 15-year-old girl with severe aplastic anemia who underwent orthotopic liver transplantation 5 years ago for fulminant hepatic failure during the course of immunodeficiency of unknown etiology. She previously exhibited similar immunodeficiency and experienced recurrent viral infections. She developed jaundice at 9 years of age and was diagnosed with fulminant hepatitis. One month later, she underwent living donor liver transplantation, with the donor being her father. Five years after the liver transplant, pancytopenia was noted; she did not respond to treatment with increasing doses of tacrolimus/prednisone and administration of granulocyte-colony stimulating factor. Bone marrow biopsy was performed, and severe aplastic anemia was diagnosed. Six years after the liver transplant, she underwent bone marrow transplantation (BMT), with the donor being her HLA-matched sibling. However, she developed liver dysfunction with recovery of white blood cells. She developed sepsis, which eventually led to her death on day 30 after BMT.

Efficacy and safety of pulse steroid therapy in Japanese pediatric patients with ulcerative colitis: a survey of the Japanese Society for Pediatric Inflammatory Bowel Disease

AIMS

We have evaluated the therapeutic efficacy and safety of pulse steroid therapy for ulcerative colitis (UC) in a Japanese pediatric population by means of a survey.

METHODS

A questionnaire on UC patients treated with therapy between 2002 and 2006 was sent to 37 members of the Japanese Society for Pediatric Inflammatory Bowel Disease.

RESULTS

21 of 62 cases in 6 of 19 centers registered in this study had been treated with pulse steroid therapy. The success rate of remission induction with this treatment was 55%, and improvement was observed in all cases in which remission was not achieved. There were no reports of any obvious side effects. The most common reason for using pulse steroid therapy was for remission induction in relapsed cases. Over the course of 12 (or fewer) months, the number of cases in which remission was maintained was only 1 in 4. However, the amount of concomitant steroid use had significantly decreased after 1 year.

CONCLUSIONS

This survey shows that in Japan, pulse steroid therapy is used for a relatively large number of children with UC and is as an effective method of remission induction that has few side effects.

Apoptosis under hypercytokinemia is a possible pathogenesis in influenza-associated encephalopathy

BACKGROUND

Influenza-associated encephalopathy is reported to be frequent in Japan and East Asia. No evaluating markers except interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha and no likely pathological mechanism for the disease have yet been elucidated.

METHODS

In this study, influenza-associated encephalopathy was defined by clinical symptoms, and the use of an anti-influenza antibody test and/or influenza antigen detection kits, as well as computed tomography and/or magnetic resonance imaging. The levels of proinflammatory cytokines, acute phase proteins, endothelial markers and cytochrome c were compared in sera from 11 patients with and 42 without encephalopathy.

RESULTS

Cytochrome c concentration in sera from patients with encephalopathy was markedly increased compared with that from patients without encephalopathy and normal controls. Although levels of several other proinflammatory cytokines and acute phase proteins such as TNF-alpha and IL-8 were also elevated in patients with influenza virus infection, the difference between those with and without encephalopathy, though significant, was less dramatic. The mean serum concentration of cytochrome c in 11 patients with encephalopathy, consisting of four deceased, four with and three without residual central nervous system sequelae, was 26.7 +/- 19.5 ng/mL on admission. In contrast, cytochrome c levels in 42 patients without encephalopathy were 0.3 +/- 0.7 ng/mL.

CONCLUSION

The present results indicate that cytochrome c is a useful marker to follow patients with influenza-associated encephalopathy and suggest that an apoptosis of cells in several organs including the cerebrum and liver under the influence of hypercytokinemia is a possible mechanism of the disease.

Thalidomide therapy for infantile-onset Crohn's disease

A 6-month-old boy was diagnosed as having Crohn's disease (CD) by the endoscopic examination. Primary immunodeficiency syndrome was initially suspected due to a refractory infection that occurred just after birth and a family history that his older brother died at the age of 3 months of septicemia associated with perirectal abscess. Thalidomide was used because conventional medical treatment by steroids and immunosuppressives was ineffective. Thalidomide improved the symptoms of diarrhea, abdominal pain, high fever and fistula, and the PCDAI score decreased markedly from 45 to 15. Although thalidomide was discontinued after three months because of the onset of side effects, including edema, rash and the peripheral neuropathy, the effect on the fistula closure was maintained over a long period of time. Further studies will be necessary to determine the dosage of thalidomide that does not elicit side effects, but thalidomide seems to be effective in patients with refractory CD. Infantile CD is very rare and the diagnosis is often delayed. CD is generally resistant to medical treatment. More detailed information of infantile CD will be needed to elucidate the pathogenesis of this disease and progress of treatment. Recently the incidence of inflammatory bowel diseases has increased. CD should be suspected in any infant with the perianal lesion (fissures, fistula, skin tag and abscesses) especially when prolonged gastrointestinal symptoms, stomatitis or fever coexist.

Guidelines for treatment of ulcerative colitis in children

This paper introduces the guidelines for treatment of ulcerative colitis in children, created by the working group of the Japanese Society for Pediatric Gastroenterology, Hepatology and Nutrition (Chair: Yuichiro Yamashiro) and the Japanese Society for Pediatric Inflammatory Bowel Disease (IBD) (Chair: Akio Kobayashi). The ideas of the working group, with regard to the fundamental differences in medical treatment between children and adults, included: (1) for children, intensive medical treatment including appropriate systemic management is important during the acute phase of illness. (2) Treatment with steroids, which can cause growth disturbances, should not be continued for long periods of time. (3) Pulsed steroid therapy, selective removal of blood cells, and intravenous infusion of cyclosporin should be included in the therapeutic option for severe and fluminant cases.

Accuracy of the stool antigen test for the diagnosis of childhood Helicobacter pylori infection: a multicenter Japanese study

OBJECTIVE

The (13)C-urea breath test (UBT) has been accepted as a reliable noninvasive test for detecting Helicobacter pylori infection. Recently, another noninvasive test, a new enzyme immunoassay for H. pylori antigens in stool, has been widely investigated for its clinical usefulness. The purpose of this multicenter study was to evaluate the diagnostic accuracy of the stool antigen test in Japanese children.

METHODS

A total of 264 children (148 male and 116 female; mean age 9.2 yr, range 2-17 yr) who underwent (13)C-UBT and the stool antigen test were studied. The diagnosis in these patients was gastritis (n = 49), gastric ulcer (n = 4), duodenal ulcer (n = 24), recurrent abdominal pain (n = 43), and other conditions (n = 144). The stool antigen test was performed using the HpSA ELISA (Premier Platinum HpSA, Meridian Diagnostics). According to manufacturer's instructions, an absorbance at 450/630 nm of <0.100, > or =0.120, and 0.100-0.119 was defined as negative, positive, and indeterminate, respectively. Based on the (13)C-UBT with a cutoff value of 3.5 per mil, the performance of HpSA was studied. In 21 patients who received eradication therapy, the HpSA was performed at baseline and at 1, 2, and 6 months after completion of therapy. Eradication of H. pylori was confirmed by (13)C-UBT at 2 or 3 months of follow-up.

RESULTS

(13)C-UBT showed that 76 children were infected with H. pylori and 188 were not infected. In these same children, HpSA results were positive in 77 children, negative in 183, and indeterminate in four. The overall sensitivity, specificity, and accuracy of the test were 96.0% (95% CI = 88.6-99.2%), 96.8% (95% CI = 94.2-99.3%), and 96.5% (95% CI = 94.3-98.8%), respectively. There were no significant differences in these results among age groups of < or =5, 6-10, and > or =11 yr. Receiver operating characteristic curve analysis demonstrated that the best cutoff value of absorbance at 450/630 nm was 0.110. When a single cutoff value of 0.110 without indeterminate results was used, the sensitivity, specificity, and accuracy were 96.1% (95% CI = 90.8-99.7%), 96.3% (95% CI = 93.6-99.0%), and 96.2% (95% CI = 93.9-98.5%), respectively. In 19 patients in whom H. pylori was successfully eradicated, HpSA results were negative at 1 month of follow-up and remained negative through 6 months.

CONCLUSIONS

The HpSA is an accurate test for the detection of H. pylori infection in all age groups of children.

[Exchange transfusions in sepsis after the pediatric open heart surgery]

We experienced 2 cases of septic children after open heart surgery. Both of them recovered by using exchange blood transfusion technique. We use irradiated and dialysed fresh blood for exchange blood transfusion. After this procedure, they recovered from sepsis, as the datas improving, white blood cell reduced from 19,700 +/- 3,710 to 8,200 +/- 2,360, CRP reduced from 5.46 +/- 1.65 to 1.89 +/- 0.70, T-Bil reduced from 7.61 +/- 2.66 to 3.02 +/- 0.89, and BUN reduced from 525.92 +/- 6.64 to 19.76 +/- 5.34. Furthermore, blood pressure and urine volume were stable between exchange blood transfusion, although after open heart surgery. Therefore this procedure has benefits for the compromised, septic patients, performed open heart surgery, because of its stability of the circulating circumstances. And using the irradiated and dialysed fresh blood provides stable condition eventhough under high dose catecholamine use.

Sustained enhancement of Ca(2+) influx by glibenclamide induces apoptosis in RINm5F cells

Cytosolic Ca(2+) elevations are known to be involved in triggering apoptosis in many tissues, but the effect of sustained enhancement of Ca(2+) influx on apoptosis in beta cells remains unknown. We have found that the viability of RINm5F cells is decreased dose-dependently by continuous exposure to glibenclamide at concentrations from 10(-7) to 10(-4) M, and that this effect is partially ameliorated by pretreatment with cycloheximide. Electrophoresis of the cells exposed to glibenclamide revealed ladder-like fragmentation characteristic of apoptosis, and which also is suppressed by cycloheximide pretreatment. By using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining, we detected increased DNA fragmentation in the nuclei of the cells exposed to glibenclamide, and staining with Hoechst 33342 and propidium iodide showed a dose-dependent increase in the number of cells with the chromatin condensation and fragmentation in their nuclei that is characteristic of apoptosis. The effects of glibenclamide on cell viability and apoptotic cell death were partially inhibited by treatment with Ca(2+) channel blocker, and by reducing the extracellular Ca(2+) concentration during glibenclamide exposure, suggesting that they may be derived from increased Ca(2+) influx. Furthermore, only the percentage of apoptotic cells, and not that of necrotic cells, increased with the increasing intracellular Ca(2+) concentration during glibenclamide exposure. In conclusion, we have demonstrated that the sustained enhancement of Ca(2+) influx caused by glibenclamide exposure can induce apoptotic cell death in a pure beta cell line.

Wortmannin, a PI3-kinase inhibitor: promoting effect on insulin secretion from pancreatic beta cells through a cAMP-dependent pathway

To determine the role of phosphatidylinositol 3-kinase (PI3-kinase) in the regulation of insulin secretion, we examined the effect of wortmannin, a PI3-kinase inhibitor, on insulin secretion using the isolated perfused rat pancreas and freshly isolated islets. In the perfused pancreas, 10(-8) M wortmannin significantly enhanced the insulin secretion induced by the combination of 8.3 mM glucose and 10(-5) M forskolin. In isolated islets, cyclic AMP (cAMP) content was significantly increased by wortmannin in the presence of 3.3 mM, 8.3 mM, and 16.7 mM glucose with or without forskolin. In the presence of 16.7 mM glucose with or without forskolin, wortmannin promoted insulin secretion significantly. On the other hand, in the presence of 8.3 mM glucose with forskolin, wortmannin augmented insulin secretion significantly; although wortmannin tended to promote insulin secretion in the presence of glucose alone, it was not significant. To determine if wortmannin increases cAMP content by promoting cAMP production or by inhibiting cAMP reduction, we examined the effects of wortmannin on 10(-4) M 3-isobutyl-1-methylxantine (IBMX)-induced insulin secretion and cAMP content. In contrast to the effect on forskolin-induced secretion, wortmannin had no effect on IBMX-induced insulin secretion or cAMP content. Moreover, wortmannin had no effect on nonhydrolyzable cAMP analog-induced insulin secretion in the perfusion study. These data indicate that wortmannin induces insulin secretion by inhibiting phosphodiesterase to increase cAMP content, and suggest that PI3-kinase inhibits insulin secretion by activating phosphodiesterase to reduce cAMP content.

The MH1 domains of smad2 and smad3 are involved in the regulation of the ALK7 signals

The biological responses of the transforming growth factor beta (TGF-beta) superfamily are induced by activation of a receptor complex and Smad proteins. We surveyed the TGF-beta superfamily receptors using the degenerate PCR strategy, and found activin receptor-like kinase 7 (ALK7) to be abundantly expressed in fetal rat pancreatic islets. ALK7 is also expressed in adult rat islets and pancreatic beta-cell-derived MIN6 cells. The constitutively active form of ALK7, ALK7(T194D), activated Smad3 and a chimeric Smad protein, Smad3-2, containing the MH1 domain of Smad3 and the MH2 domain of Smad2, and translocated them to nuclei and then induced activation of the human PAI-1 promoter. However, neither Smad2 nor Smad2-3 protein, containing the MH1 domain of Smad2 and the MH2 domain of Smad3 were activated. These results indicate that the ALK7 signal regulates nuclear localization and activation of Smad2 and Smad3, and the MH1 domain of Smad2 has inhibitory effects on the nuclear localization.

Transcriptional repressors are increased in pancreatic islets of type 2 diabetic rats

To further clarify the mechanism of impaired insulin gene transcription in the diabetic state, we investigated the expression and function of the transcriptional repressor CREM (CRE modulator) in rat pancreatic islets. The CREM gene generates both transcriptional activators and repressors by alternative splicing and an intronic promoter. We isolated a novel alternatively spliced CREM isoform, CREM-17X, which efficiently represses insulin gene transcription, in addition to the three previously reported repressors. We also compared mRNA levels of insulin and the CREM repressors in pancreatic islets of Wistar and GK (Goto-Kakizaki) rats, the well-characterized spontaneous animal model of type 2 diabetes. The CREM repressor levels are increased, and the expression of insulin mRNA is decreased in GK rats, suggesting that increased CREM repressor expression in pancreatic islets could contribute to the decreased insulin gene transcription that results in impaired insulin secretion in type 2 diabetes.

An evaluation of infants' growth in the Kingdom of Nepal

BACKGROUND

The His Majesty's Government/Japan International Cooperation Agency Primary Health Care Project began in April 1993 in collaboration with the Saitama Prefectural Government, for the purpose of improving the health status of the people in model districts of the Kingdom of Nepal. Growth monitoring is one of the basic methods that defines the health and nutritional status of children.

METHODS

Anthropometric indices were measured in 759 children in the Bhaktapur district. We used the World Health Organization prototype growth chart and national growth standard for Japanese children (1990) to analyze the growth data.

RESULTS

We found that the average bodyweight growth curve of children up to 4 months of age followed the 50th percentile reference curve. For children of 5-12 months of age, there was a delay in bodyweight gain and the growth curve reached the 3rd percentile curve. For children more than 1 year old, the growth curve moved below the third percentile curve. Catch-up growth did not occur before the children reached 5 years of age. The main causes of catch-up growth being hampered were chronic undernutrition and inadequate nutritional balance.

CONCLUSIONS

As this was the first opportunity to evaluate infant growth in this district, the first important consequence of the results was to analyze the causes of growth faltering and failure-to-thrive in Nepalese children. Even more important, was the need to give appropriate counseling on improving feeding and other health-related practices, and the most important consequence of all was to instruct Nepalese health workers that utilizing the growth charts is an integral part of health care.

Tyrosinemia type I-like disease: a possible manifestation of 3-oxo-delta 4-steroid 5 beta-reductase deficiency

BACKGROUND

It has been suggested that quantitative analysis of urinary bile acids may help to distinguish primary 3-oxo-delta 4-steroid 5 beta-reductase deficiency from the excretion of 3-oxo-delta 4 bile acids that occurs as a result of liver damage.

METHODS

Urinary bile acids were quantitatively analyzed by gas chromatography-mass spectrometry in four Japanese patients with severe neonatal cholestasis associated with hypertyrosinemia without urinary succinylacetone (i.e. tyrosinemia type I-like disease). These four patients represented sporadic cases.

RESULTS

Large amounts of 3-oxo-delta 4 bile acids were detected, which comprised greater than 80% of the total urinary bile acids. Small amounts of allo-bile acids and primary bile acids were also detected, comprising less than 1% and 15% of the total urinary bile acids, respectively.

CONCLUSIONS

It was suspected that these four patients had a primary 3-oxo-delta 4-steroid 5 beta-reductase deficiency. However, it is possible that some patients in this study may have had a secondary 3-oxo-delta 4-steroid 5 beta-reductase deficiency, caused by idiopathic neonatal cholestatic liver failure.

A syndrome of peripheral blood T-cell infection with Epstein-Barr virus (EBV) followed by EBV-positive T-cell lymphoma

The role of Epstein-Barr virus (EBV) in the pathogenesis of severe, chronic active EBV infection and its complications is unclear. We investigated two Japanese patients diagnosed with severe, chronic active EBV infection who subsequently developed EBV-positive T-cell lymphoma. The patients displayed abnormally high antibody titers to EBV antigens, and had evidence of peripheral blood CD4(+) T-cell infection with EBV, 19 months and 3 months, respectively, before the diagnosis of EBV-positive T-cell lymphoma. The lymphomas were infected with monoclonal EBV and expressed the EBV latency genes EBNA-1, LMP-1, and LMP-2. Genetic studies showed that the virus detected in the T-cell lymphoma was indistinguishable, with respect to type and previously defined LMP-1 and EBNA-1 gene variations, from virus detected in the peripheral blood T cells 19 months earlier. These studies support an important pathogenetic role of T-cell infection with EBV in chronic active EBV infection and in the EBV-positive T-cell lymphoma that followed.

Gastric inhibitory polypeptide activates MAP kinase through the wortmannin-sensitive and -insensitive pathways

The signal transduction pathways of a cloned human gastric inhibitory polypeptide (GIP) receptor have been investigated in CHO cells stably expressing this receptor. Exposure of GIP receptor expressing cells to GIP significantly increased MAP kinase activity. Time course analysis showed that a rapid and marked increase in MAP kinase activation was detected and that this activation reached maximal levels 10 min after the addition of GIP. Dose-response analysis showed that GIP activated MAP kinase activity in a dose-dependent manner with an ED50 value of 5.9 x 10(-10) M of GIP. Wortmannin, a potent inhibitor of phosphatidylinositol 3-kinase (PI3-kinase), partially inhibited GIP-induced MAP kinase activation, suggesting that GIP activates MAP kinase through two different, wortmannin-sensitive and -insensitive pathways. It has been demonstrated that in CHO cells cAMP attenuates MAP kinase activity by inhibiting Raf-1. Since GIP elevates intracellular cAMP, we examined the effects of cAMP on MAP kinase activation. Interestingly, forskolin, which increased intracellular cAMP levels, significantly inhibited MAP kinase activation by GIP, but did not affect MAP kinase activation by GIP in the presence of wortmannin, suggesting that the wortmannin-sensitive pathway activates an MAP kinase cascade at or above the level of Raf-1 and that the wortmannin-insensitive pathway activates an MAP kinase cascade below the level of Raf-1. These findings demonstrate that the GIP receptor is linked to the MAP kinase cascade via at least two different pathways.

Identification of two missense mutations in the GIP receptor gene: a functional study and association analysis with NIDDM: no evidence of association with Japanese NIDDM subjects

Gastric inhibitory polypeptide (GIP) potently stimulates insulin secretion from pancreatic islets in the presence of glucose as an incretin. Because the insulinotropic effect of GIP is reduced in NIDDM, it should be clarified whether defects in the GIP receptor gene contribute to the impaired insulin secretion in NIDDM. Using genomic DNA samples from Japanese NIDDM and non-NIDDM subjects, we have investigated the entire coding region of the GIP receptor gene by polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP). We have identified two missense mutations, Gly198-->Cys (Gly198Cys) in exon 7 and Glu354-->Gln (Glu354Gln) in exon 12. Investigation of the function of GIP receptor with either of these mutations reveals a half-maximal stimulation value of GIP-induced cAMP response in Chinese hamster ovary cells expressing the GIP receptor with Gly198Cys of 6.3 +/- 1.2 x 10(-10) mol/l (n = 3), which was considerably higher than that of the normal GIP receptor, 9.4 +/- 3.8 x 10(-12) mol/l GIP (n = 3), whereas that of the GIP receptor with Glu354Gln was not significantly different from that of the normal GIP receptor. To assess the possible role of the GIP receptor gene in genetic susceptibility to NIDDM, we have examined the allelic frequencies of Gly198Cys and Glu354Gln in NIDDM and control subjects. Association studies show no relationship between NIDDM and either of the two mutations.

[A quantitative analysis of the cells infected with Epstein-Barr virus in the peripheral blood mononuclear cells derived from the patients with infectious mononucleosis]

The quantitative analysis of the cells infected with Epstein-Barr virus was performed on the peripheral blood mononuclear cells from the patients with infectious mononucleosis, by using in situ hybridization with Epstein-Barr virus encoded small nuclear RNA1 (EBER1). An alkaline-phosphatase conjugated oligonucleotide probe complementary to EBER1 was used as an antisense probe, while oligonucleotide DNA probe compatible with the sequence of EBER1 was used as a sense probe, control probe. The EBER1 positive cells on the slide-glass were enumerated microscopically. In situ hybridization revealed that 50,000 peripheral blood mononuclear cells from the patients in the acute phase of infectious mononucleosis contained 35 +/- 36 cells infected with Epstein-Barr virus (n = 11). The cells infected with Epstein-Barr virus apparently decreased in the convalescence of all the patients with infectious mononucleosis and the mean of the cells infected with Epstein-Barr virus was 3 +/- 4 in the convalescence (n = 6) (p < 0.02). On the other hand, no positive cells were detected in healthy individuals with past-infection of Epstein-Barr virus (n = 10) or without any previous Epstein-Barr virus infection (n = 11). The striking increase of the cells with Epstein-Barr virus genome was clearly demonstrated in the peripheral blood mononuclear cells from the patients with infectious mononucleosis.

Effector coupling of somatostatin receptor subtypes on human endocrine tumors

Effector coupling of somatostatin receptor subtypes sst1 and sst2 was examined in a reconstituted system. Forskolin-stimulated cyclic adenosine monophosphate (cAMP) formation was inhibited 66% by somatostatin (SRIF-14) in CHO cells expressing somatostatin receptor 1(sst1) (CHO-SR1), but not sst2, in a dose-dependent manner with an ED50 of 1 x 10(-9) mol/L SRIF-14. The inhibition was blocked by pertussis toxin (PTX), indicating that sst1 is coupled to adenylyl cyclase via PTX-sensitive Gi protein. In CHO cells, Gi alpha 2 and Gi alpha 3 mRNAs were detected. In adenylyl cyclase assays, 1 mumol/L SRIF-14 caused a 16% inhibition of forskolin-stimulated adenyly cyclase activity. Preincubation with Gi alpha 3, but not Gi alpha 1/Gi alpha 2, antiserum blocked this inhibition. By contrast, sst2 is coupled to adenylyl cyclase via Gi alpha 1. In cells expressing sst2 with Gi alpha 1(CHO-SR2G1), SRIF-14 significantly inhibited forskolin-stimulated cAMP formation by 53% and with an ED50 at 4 x 10(-9)mmol/L SRIF-14, which was completely blocked by PTX; ED50 values for sst1 and sst2 agree with the IC50 values in binding assays. In CHO-SR1, the rank of potency of agonists affecting adenyl cyclase was SRIF-14 = SRIF-28 > RC 160 > SMS 201-995. In CHO-SR2G1, the rank was RC-160 > SRIF-14 = SRIF-28 > SMS 201-995.

Multiple effector coupling of somatostatin receptor subtype SSTR1

The signal transduction pathways of a cloned human somatostatin receptor subtype, SSTR1, have been investigated in CHO cells stably expressing this receptor. In SSTR1-expressing CHO cells, somatostatin-14 inhibits forskolin-stimulated cAMP formation in a dose-dependent manner with an ED50 of 1.0 x 10(-9) M. Somatostatin-14 also stimulates inositol 1,4,5-trisphosphate formation in a dose-dependent manner with an ED50 of 4.0 x 10(-8) M. Somatostatin-14 inhibitory action on adenylyl cyclase and stimulatory action on inositol 1,4,5-trisphosphate formation are both blocked by pertussis toxin, indicating that these effects of SSTR1 are mediated by pertussis toxin-sensitive G protein(s). Antiserum against Gi alpha 3 blocked the inhibitory effects of somatostatin-14 on forskolin-stimulated adenylyl cyclase, but antiserum against Gi alpha 1/Gi alpha 2 did not, indicating that Gi alpha 3 dominantly couples SSTR1 to adenylyl cyclase. These results demonstrate that SSTR1 can be coupled to different signaling pathways to exert multiple biological effects, one of which is mediated by Gi alpha 3.

Human somatostatin receptor, SSTR2, is coupled to adenylyl cyclase in the presence of Gi alpha 1 protein

Somatostatin has been shown to exert diverse biological effects in various tissues. Recently, the human genes encoding five subtypes of somatostatin receptor (SSTR1-SSTR5) were cloned. Among these subtypes SSTR2 is present in many endocrine tumors as well as normal tissues and may mediate the effects of somatostatin analog, SMS201-995. In this study, we have investigated the intracellular effect of SSTR2 stably expressed in Chinese hamster ovary cells. Somatostatin-14 does not affect the forskolin stimulated cAMP formation when human SSTR2 is expressed in CHO cells, which lack internal Gi alpha 1 protein. However, somatostatin-14 inhibits the adenylyl cyclase in a dose dependent and pertussis toxin-sensitive manner when human SSTR2 is co-expressed with Gi alpha 1 in CHO cells. These results indicate that human SSTR2 is functionally coupled to Gi alpha 1 protein but not to Gi alpha 2 or Gi alpha 3 when expressed in CHO cells.

Identification of somatostatin receptor subtypes and an implication for the efficacy of somatostatin analogue SMS 201-995 in treatment of human endocrine tumors

The presence of somatostatin receptors has been demonstrated in various endocrine tumors as well as in normal tissues. We recently have cloned five human somatostatin receptor subtypes (SSTR1-SSTR5). These mRNAs are expressed in a tissue-specific manner. In this study, we have determined the somatostatin receptor subtypes expressed in various endocrine tumors using a reverse transcriptase polymerase chain reaction method. In two cases of glucagonoma and its metastatic lymph nodes in one case, all the SSTR subtype mRNAs except SSTR5 mRNA were expressed. In four cases of insulinoma, SSTR1 and SSTR4 mRNAs were detected, but SSTR2 mRNA was not detected in one case and SSTR3 mRNA was not detected in two cases, indicating a heterogeneous expression of SSTR subtypes in insulinomas. Interestingly, SSTR3 mRNA, which is highly expressed in rat pancreatic islets, is not expressed in normal human pancreatic islets, while SSTR1, SSTR2, and SSTR4 mRNAs are expressed. In three cases of pheochromocytoma, SSTR1 and SSTR2 mRNAs were detected, showing an expression pattern identical to that of normal adrenal gland. In a carcinoid, SSTR1 and SSTR4 mRNAs were detected. We have also found that human SSTR2 shows a high affinity for SMS 201-995, which has been used clinically for the treatment of endocrine tumors. Since SMS 201-995 was effective in the treatment of a patient with glucagonoma in which SSTR2 mRNA was present, but had no effect in a patient with carcinoid in which SSTR2 mRNA was not detected, this study suggests that the efficacy of SMS 201-995 may depend, at least in part, on the expression of SSTR2 in tumors.

Cloning, functional expression and pharmacological characterization of a fourth (hSSTR4) and a fifth (hSSTR5) human somatostatin receptor subtype

Somatostatin exerts diverse effects in various tissues upon binding its specific membrane receptors. Recently, we have cloned three different somatostatin receptor subtypes. Here we report the sequence and functional expression of a fourth and a fifth human somatostatin receptor subtype, termed hSSTR4 and hSSTR5, respectively. The hSSTR4 encodes a protein of 388 amino acids and the hSSTR5 is a protein of 364 amino acids. There is 42-60% identity among the amino acid sequences of the five human somatostatin receptor subtypes identified to date. RNA blotting studies reveal that the hSSTR4 is expressed as a single transcript of 4.8 kb in MIA PaCa-2 cells, a cell line derived from human pancreatic cancer while the hSSTR5 is undetectable in the tissues examined. The hSSTR4 and hSSTR5 transiently expressed in COS1 cells exhibit specific binding to somatostatin-14 with IC50 values of 1.6 and 0.16 nM, respectively. We also have characterized the binding affinity of various somatostatin analogues to the hSSTR4 and hSSTR5. The rank of the potency of the analogues are: somatostatin-14 = somatostatin-28 >> RC-160 >> SMS201-995 for the hSSTR4 and somatostatin-28 > somatostatin-14 >> RC-160 > SMS201-995 for the hSSTR5. These results suggest that diverse actions of somatostatin are mediated by at least five somatostatin receptor subtypes with potentially different function.

Duodenal findings on ultrasound in children with Schonlein-Henoch purpura and gastrointestinal symptoms

Abdominal ultrasonic examination was performed in 14 patients with Schonlein-Henoch purpura (SHP). Thickening of the duodenal wall was observed in nine (82%) of the 11 with such gastrointestinal (GI) symptoms as severe abdominal pain or bleeding. The thickened duodenal wall showed a high echogenicity. Enlargement of the duodenal lumen was seen in seven (64%) patients with GI symptoms. These findings had been observed in four patients before SHP was diagnosed on the basis of the peculiar skin lesions. In three cases of SHP without GI symptoms, those changes were absent. Four cases of ulcerative colitis, three of bacterial enterocolitis (two Yersinia and one Klebsiella), and five without SHP and any GI problems did not exhibit such duodenal abnormalities. On subsequent endoscopic study, mucosal edema and multiple hemorrhagic erosions were seen, especially at the second portion of the duodenum in two cases of SHP. Biopsy specimens from the duodenum of those cases showed leukocytoclastic vasculitis, suggested by the ultrasound (US) findings. It is important to consider the duodenal changes carefully when US is performed in patients with severe GI symptoms of unknown origin. The characteristic duodenal findings described suggest the differential diagnosis of SHP, which usually requires no surgical intervention.

Somatostatin receptors, an expanding gene family: cloning and functional characterization of human SSTR3, a protein coupled to adenylyl cyclase

We previously reported the cloning of two distinct somatostatin receptor (SSTR) subtypes, SSTR1 and SSTR2. Although both SSTR1 and SSTR2 bound somatostatin specifically and with high affinity, neither was coupled to adenylyl cyclase, a major cellular effector of somatostatin's actions. Here we report the cloning and functional characterization of a third member of the SSTR family. Human SSTR3 is a protein of 418 amino acids and has 45% and 46% identity with human SSTR1 and SSTR2, respectively. RNA blotting studies showed that SSTR3 mRNA could be readily detected in brain and pancreatic islets. The pharmacological properties of human SSTR3 were characterized by transiently expressing the human SSTR3 gene in COS-1 cells. Membranes from cells expressing human SSTR3 bound the somatostatin agonist [125I]CGP 23996 specifically and with high affinity, with a rank order of potency of somatostatin-28 = CGP 23996 > somatostatin-14 > SMS-201-995. Studies using cells transiently coexpressing the human dopamine D1 receptor and human SSTR3 showed that somatostatin was able to inhibit dopamine-stimulated cAMP formation in a dose-dependent manner, indicating that SSTR3 was functionally coupled to adenylyl cyclase. These results indicate that the diverse biological effects of somatostatin are mediated by a family of receptor with distinct, but overlapping, tissue distributions, unique pharmacological properties, and potentially different functions.

Study to establish normal values for portal vein blood flow in children using a duplex ultrasound system

Portal vein blood flow in healthy children was measured using a duplex ultrasound system consisting of a B mode linear scanner and a single Doppler transducer. Portal blood flow volume (PBFV) correlated with age, height, weight and body surface area. Increases in PBFV with age were greater in boys than girls. A correlation was noted between the diameter of the portal vein and PBFV (r = 0.89). However, the maximum portal blood flow velocity (Vmax) did not correlate with age, height, weight or body surface area. Increases in PBFV in accordance with physical development was thought to depend mainly on widening of the portal vein and not on acceleration of portal blood flow velocity. The formula for calculating PBFV by multivaliate statistical analysis is as follows: PBFV(ml/min) = 30.1 x age(yrs) - 1.07 x height(cm) = 3.31 x weight(kg). Portal vein flowmetry using a duplex ultrasound system may be useful for evaluation of the hepatic circulation in children.

Changes of anti-HB core antibody in children with positive HB surface antigen

To elucidate the clinical courses of children chronically infected with HB virus (HBV), RIA values of anti-HBc were surveyed in 88 cases with positive HBs antigen. Among 56 children with positive HBe antigen, 20 had negative, indefinite or low titers of anti-HBc, and 18 (90%) of them had no liver malfunction. Out of 30 cases with abnormal liver function tests, 28 (93%) had high titers of anti-HBc. Follow-up study for a period of over 12 months reveals that serum HBe antigen disappeared in 10 out of the 40 cases who were positive for this antigen. All of the 10 cases had liver malfunction and high levels of anti-HBc. Among 12 children with initially positive anti-HBe, five had high titers of anti-HBc. Out of 13 children who once had high levels of anti-HBc, 3 showed reduction in titers of anti-HBc during the follow-up period in accordance with decrease in activity of hepatitis. Four out of 16 who initially had HBe antigen and low titers of anti-HBc showed high titers of anti-HBc during the observation period, while only one of 33 who had HBeAg and a high titer of anti-HBc went to the low titer group of anti-HBc, though continuously positive for HBe antigen. We presume that high levels of anti-HBc indicate previous or current liver damage due to HBV infection, while low titers of anti-HBc indicate that HBV-derived liver damage has not yet occurred or that a long time has passed since the last episode of liver damage subsided.

Effect of diabetes on the free polyol pattern in cataractous lenses

To obtain information about the effects of lenticular polyols on the prevention, initial stages, and development of diabetic cataracts, we identified and determined with gas-liquid chromatography or gas-liquid chromatography/mass spectrometry eight polyols in cataractous lenses of non-insulin-dependent diabetes mellitus patients and nondiabetic subjects. In the diabetics' lenses, the concentrations of polyols (e.g., sorbitol, fructose, mannitol, and adonitol) were higher than in the nondiabetics' lenses, whereas the concentration of 1-deoxyglucose was lower. The mean concentration of myo-inositol in lenses of diabetics was lower than that of nondiabetics, but this difference was statistically not significant. The total content of eight polyols in the diabetics' lenses did not differ significantly from that in the nondiabetics. In the lenses of diabetics, the content of glucose correlated positively with that of adonitol, fructose, and sorbitol. In the lenses of nondiabetics, the content of glucose correlated positively with that of mannitol and inversely with that of 1-deoxyglucose and myo-inositol. In diabetics, hemoglobin A1 (%) correlated positively with the concentration of adonitol in the lenses and inversely with the concentration of lens myo-inositol; however, it did not correlate with the concentration of glucose in lenses. Regulation of both the metabolism of lenticular polyols and the pattern of polyols in serum may be necessary for normalizing lenticular polyol content.

Effect of diabetes on the free polyol pattern in cataractous lenses

To obtain information about the effects of lenticular polyols on the prevention, initial stages, and development of diabetic cataracts, we identified and determined with gas-liquid chromatography or gas-liquid chromatography/mass spectrometry eight polyols in cataractous lenses of non-insulin-dependent diabetes mellitus patients and nondiabetic subjects. In the diabetics' lenses, the concentrations of polyols (e.g., sorbitol, fructose, mannitol, and adonitol) were higher than in the nondiabetics' lenses, whereas the concentration of 1-deoxyglucose was lower. The mean concentration of myo-inositol in lenses of diabetics was lower than that of nondiabetics, but this difference was statistically not significant. The total content of eight polyols in the diabetics' lenses did not differ significantly from that in the nondiabetics. In the lenses of diabetics, the content of glucose correlated positively with that of adonitol, fructose, and sorbitol. In the lenses of nondiabetics, the content of glucose correlated positively with that of mannitol and inversely with that of 1-deoxyglucose and myo-inositol. In diabetics, hemoglobin A1 (%) correlated positively with the concentration of adonitol in the lenses and inversely with the concentration of lens myo-inositol; however, it did not correlate with the concentration of glucose in lenses. Regulation of both the metabolism of lenticular polyols and the pattern of polyols in serum may be necessary for normalizing lenticular polyol content.