Delta-induced Notch signaling mediated by RBP-J inhibits MyoD expression and myogenesis

Signaling induced by interaction between the receptor Notch and its ligand Delta plays an important role in cell fate determination in vertebrates as well as invertebrates. Vertebrate Notch signaling has been investigated using its constitutively active form, i.e. the truncated intracellular region which is believed to mimic Notch-Delta signaling by interaction with a DNA-binding protein RBP-J. However, the molecular mechanism for Notch signaling triggered by ligand binding, which leads to inhibition of differentiation, is not clear. We have established a myeloma cell line expressing mouse Delta1 on its cell surface which can block muscle differentiation by co-culture with C2C12 muscle progenitor cells. We showed that Delta-induced Notch signaling stimulated transcriptional activation of RBP-J binding motif, containing promoters including the HES1 promoter. Furthermore, ligand-induced Notch signaling up-regulated HES1 mRNA expression within 1 h and subsequently reduced expression of MyoD mRNA. Since cycloheximide treatment did not inhibit induction of HES1 mRNA, the HES1 promoter appears to be a primary target of activated Notch. In addition, a transcriptionally active form of RBP-J, i.e. VP16-RBP-J, inhibited muscle differentiation of C2C12 cells by blocking the expression of MyoD protein. These results suggest that HES1 induction by the Delta1/Notch signaling is mediated by RBP-J and blocks myogenic differentiation of C2C12 cells by subsequent inhibition of MyoD expression.

Prevalence of fatty liver in a general population of Okinawa, Japan

A total of 2,574 residents in Yaeyama District of Okinawa, Japan, were investigated using real time ultrasonography to determine the real prevalence of fatty liver in the general population and to define its associated factors. Overall prevalence of fatty liver was 14.0%. Prevalence of fatty liver in persons under 19 years old was only 1.2%, and increased with age to a maximum in persons 40-49 years of age and then decreased. For persons over 20 years old, obesity index and serum levels of triglyceride and total cholesterol were measured, and alcohol consumption was asked. Prevalence of fatty liver was significantly higher in drinkers than non-drinkers (p less than 0.01), and increased with alcohol consumption. Furthermore, in persons not suffering from obesity prevalence of fatty liver was significantly higher in drinkers than in non-drinkers (p less than 0.001). The results of logistic regression analysis indicated that obesity and elevated serum triglyceride level in both sexes, and alcohol in males were significant predictors of fatty liver. In conclusion, prevalence of fatty liver increased with age to a maximum in persons 40-49 years of age and overall was 14.0%. Obesity was the strongest associated factor in both sexes and in males alcohol was also a strong factor.

Extensibility of the lumbar and sacral cord. Pathophysiology of the tethered spinal cord in cats

Tethered spinal cord, or tethered cord syndrome, describes a disorder manifested by progressive motor and sensory deficit in the legs and by incontinence. Tethered cord syndrome occurs when the elongated spinal cord is anchored by a thick filum terminale or other pathological structures. The underlying mechanism is impairment of oxidative metabolism in the lumbosacral cord. The authors studied the extensibility of various parts of lumbar, sacral, and coccygeal segments in experimental animals and correlated this with the oxidative metabolism in these segments. The filum terminale possesses far greater extensibility than any spinal cord segments and functions as a buffer in preventing the cord from overstretching. The lumbar, sacral, and coccygeal segments elongate under traction only below the attachment of the lowest pair of dentate ligaments. The lower the cord segment, the greater the percentage of elongation in spite of limited elasticity of the cord tissue; this greater percentage of elongation of the spinal cord correlates with increasing impairment of the oxidative metabolism and more severe neurological deficit. These findings explain such symptoms and signs as motor and sensory deficits in the legs associated with the human tethered cord syndrome, and correspond with the high clinical incidence of incontinence. The lower spinal cord segments elongated promptly within 3 seconds after the start of traction. This implies that repeated acute hyperextension and hyperflexion, as occurs in humans, may accentuate oxidative metabolic changes that have already been caused by chronic cord tethering. The authors conclude that the elongation of the spinal cord under traction parallels the degree of metabolic dysfunction.

New model of acute necrotizing pancreatitis induced by excessive doses of arginine in rats

We examined the biological and histologic characteristics of a new experimental model of acute necrotizing pancreatitis induced by excessive doses of arginine in rats. Rats were given a single intraperitoneal injection of 500 mg/100 g body weight of L-arginine. At 12-24 hr after the arginine injection, serum levels of amylase, lipase, and anionic trypsin(ogen) reached respective peak values 2, 5, and 20 times those of control rats without arginine and returned to control levels after 24-48 hr. The contents of pancreatic protein, DNA, and digestive enzymes were markedly reduced after the arginine injection and reached their nadirs at 72 hr. After 14 days these levels were almost normal. Histologic examination revealed a number of small vesicles within acinar cells at 6 hr, which were identified as markedly swollen mitochondria by the electron microscope. Other intracellular organelles and nuclei also showed degenerative changes. At 12 hr interstitial edema appeared, and acinar cell necrosis was seen after 24 hr. The extent and severity of necrotic changes of pancreatic exocrine tissue with inflammatory cell infiltration were maximal at 72 hr. At seven days, pancreatic acinar cells began to regenerate, and pancreatic architecture appeared almost normal after 14 days. The present study has demonstrated that the administration of excessive doses of arginine induces a new, noninvasive experimental model of acute necrotizing pancreatitis.

Microstructure and release characteristics of the minipellet, a collagen-based drug delivery system for controlled release of protein drugs

We have developed the minipellet, a matrix-type system for the sustained delivery of protein drugs using collagen as a biodegradable drug carrier. In this study, we analyzed the microstructure and release profile of the minipellet containing human serum albumin (HSA) as a model drug.The findings suggest that the minipellet has a structure in which collagen fibers are strongly oriented in the direction of extrusion from the nozzle in the molding process of the minipellet, and that HSA exists as fine particulate clusters which are homogeneously distributed among the collagen fibers in the minipellet. During release, the HSA clusters dissolve and HSA is retained within the collagen matrix as a solution.The results of release experiments indicate that HSA release from the minipellet is mainly controlled by diffusion in the collagen matrix, and that sustained release is achieved by the dense structure of the collagen matrix which is formed in the manufacture process. In addition, more detailed study suggests that the minipellet has unique directional release behavior caused by its microstructure.

Prevalence of gallstone disease in a general population of Okinawa, Japan

A total of 2,584 healthy residents in the Yaeyama District of Okinawa, Japan, were investigated in 1984 to determine the prevalence of gallstone disease and its associated factors. Diagnosis of gallstone disease was assessed by real-time ultrasonography. For participants over 20 years of age, obesity index and serum levels of total cholesterol and triglycerides were measured. Overall prevalence of gallstone disease was 3.2%. Prevalence increased with age from 0% under 19 years of age to 11.4% over 70 years of age and was higher in females (4.0%) than in males (2.5%). The results of the logistic regression analysis indicated that age and fatty liver were significant predictors of gallstone disease. The results of the automatic interaction detector analysis indicated that age and fatty liver were strong factors associated with gallstone disease and that prevalence was highest in females over age 50 with fatty liver.

Smoking increases tissue factor expression in atherosclerotic plaques: implications for plaque thrombogenicity

BACKGROUND

Smoking increases the risk of atherothrombotic events. To determine whether smoking influences plaque thrombogenicity, we examined the effect of cigarette smoking and aspirin use on tissue factor (TF) expression in atherosclerotic plaques.

METHODS AND RESULTS

A total of 23 apoE-/- mice were exposed to cigarette smoke with (n=9) or without (n=14) aspirin treatment. Eleven mice who were exposed to filtered room air served as controls. Aortic root plaques of mice exposed to smoke had higher immunoreactivity for TF (14+/-4% versus 6.4+/-3%; P=0.0005), vascular cell adhesion molecule-1 (15+/-4% versus 5+/-2%; P=0.002), and macrophages (16+/-5% versus 6+/-2%; P=0.002) compared with nonsmoking controls. Aspirin treatment attenuated smoking-induced changes in plaque composition. In human plaques obtained by carotid endarterectomy, TF immunoreactivity (8+/-5% versus 2+/-2%; P=0.0002) and activity (P=0. 03) were higher in the plaques from smokers (n=28) than those from nonsmokers (n=28). Aspirin use was associated with reduced TF expression in smokers (9+/-8% versus 3+/-4%; P=0.0017).

CONCLUSIONS

Our results suggest increased plaque TF expression and thrombogenicity as a novel mechanism for the increased risk of atherothrombotic events in smokers. Treatment with aspirin may reduce TF expression.

Characterization of the amyR gene encoding a transcriptional activator for the amylase genes in Aspergillus nidulans

The Aspergillus nidulans amyR gene and its cDNA were cloned and sequenced. The genomic gene comprised 2,092 bp, interrupted by two short introns, and encoded a cys-6 zinc transcriptional activator (AMYR) of 662 amino acid residues with a calculated molecular mass of 72,862 Da. Disruption of the amyR gene caused defects in the utilization of maltose and starch and abolished expression of the taaG2 gene encoding A. oryzae Taka-amylase A, which is inducibly and abundantly expressed in the wild-type A. nidulans. Expression of the amyR gene was under the control of the carbon catabolite repressor, CREA. The growth defect of the malA1 mutant on maltose was complemented by the amyR gene; and the amyR gene derived from the mutant possessed a single mutation, from A to T, at position 1,483, resulting in a substitution of His478 to Leu. These results indicate that the amyR gene is identical to the genetically defined malA gene. AMYR possessed five domains (Zn and MH1-MH4) homologous to Mal63p, a transcriptional activator for the genes involved in maltose utilization in Saccharomyces cerevisiae. The His478 to Leu substitution lay within the MH3 domain, corresponding to the negative regulatory domain of Mal63p which relieves the inhibitory effect on the activation function in response to maltose.

Hepatoma-specific antitumor activity of an albumin enhancer/promoter regulated herpes simplex virus in vivo

Targeting viral vectors to appropriate cell types so that normal cells are not adversely affected is an important goal for gene therapy. Previously, we described a novel approach to viral gene therapy using a conditional, replication-competent herpes simplex virus (HSV), where replication and associated cytotoxicity are limited to a specific cell-type by the regulated expression of an essential immediate-early viral gene product. In this report we analyze the hepatoma-specific replication, cytotoxicity and anti-tumor effect of recombinant HSV G92A, regulated by the albumin enhancer/promoter. G92A efficiently replicated in vitro in two human hepatoma cell lines expressing albumin, but not in four human non-hepatoma, albumin-non-expressing tumor cell lines, while all cell lines were equally susceptible to a tissue nonspecific HSV recombinant, hrR3. In vivo, G92A replicated well in subcutaneous xenografts of human hepatoma cells (Hep3B) in athymic mice, but not in non-hepatoma subcutaneous tumors (PC3 and HeLa), whereas, hrR3 replicated well in both tumor types. Intratumoral inoculation of G92A inhibited the growth of established subcutaneous hepatoma tumors in nude mice, but not prostate tumors. Replication-competent viral vectors controlled by cell-specific transcriptional regulatory sequences provide a new therapeutic strategy for tumor therapy.

Extraordinary carrier multiplication gated by a picosecond electric field pulse

The study of carrier multiplication has become an essential part of many-body physics and materials science as this multiplication directly affects nonlinear transport phenomena, and has a key role in designing efficient solar cells and electroluminescent emitters and highly sensitive photon detectors. Here we show that a 1-MVcm⁻¹ electric field of a terahertz pulse, unlike a DC bias, can generate a substantial number of electron–hole pairs, forming excitons that emit near-infrared luminescence. The bright luminescence associated with carrier multiplication suggests that carriers coherently driven by a strong electric field can efficiently gain enough kinetic energy to induce a series of impact ionizations that can increase the number of carriers by about three orders of magnitude on the picosecond time scale.

Studying carrier multiplication in materials is important to understand their transport properties and interaction with light. Hirori et al. show that intense terahertz pulses can generate electron-hole pairs in GaAs quantum wells that then emit infrared light, contrary to the effect with a DC field.

Characteristic distribution of cathepsin E which immunologically cross-reacts with the 86-kDa acid proteinase from rat gastric mucosa

The antiserum raised against the high-molecular-weight acid proteinase from rat gastric mucosa, termed 86-kDa acid proteinase, has been shown to recognize rat cathepsin E, but not cathepsin D (Muto, N. et al. (1987) J. Biochem. 101, 1069-1075). Using this specific antiserum, characteristic distribution of cathepsin E in rats was demonstrated. The enzyme was detected in a limited number of tissues, such as stomach, thymus, spleen, bladder, and erythrocyte membranes. Among them, the highest activity was observed in the stomach. In contrast, cathepsin D immunoreactive with the antiserum specific to rat gastric cathepsin D was demonstrated in all the tissues examined. Cathepsin E-type enzymes partially purified from these five tissues were precipitated in the same manner by the specific antiserum, and they had the same molecular weight, electrophoretic mobility, and resistance against denaturation by 4 M urea. These results indicate that they could be exactly classified as cathepsin E. This type of enzyme was also detectable in mice and guinea pigs, but they showed relatively weak immunoreactivities with the antiserum. Thus, it is concluded that the distribution of cathepsin E is intrinsically different from ordinary cathepsin D, suggesting that it has a different physiological role from cathepsin D.

The N- and C-terminal regions of RBP-J interact with the ankyrin repeats of Notch1 RAMIC to activate transcription

The evolutionarily-conserved DNA-binding protein RBP-J directly interacts with the RAM domain and the ankyrin (ANK) repeats of the Notch intracellular region (RAMIC), and activates transcription of downstream target genes that regulate cell differentiation. In vitro binding assays demonstrate that the truncated N- and C-terminal regions of RBP-J bind to the ANK repeats but not to the RAM domain. Using an OT11 mouse cell line, in which the RBP-J locus is disrupted, we showed that RBP-J constructs mutated in the N- and C-terminal regions were defective in their transcriptional activation induced by either RAMIC or IC (the Notch intracellular region without the RAM domain) although they had normal levels of binding activity to DNA and the RAM domain. The studies using chimeric molecules between RBP-J and its homolog RBP-L showed that the N- and C-terminal regions of RBP-J conferred the IC- as well as RAMIC-induced transactivation potential on RBP-L, which binds to the same DNA sequence as RBP-J but fails to interact with RAMIC. Taken together, these results indicate that the interactions between the N- and C-terminal regions of RBP-J and the ANK repeats of RAMIC are important for transactivation of RBP-J by RAMIC.

SS-MIX: A Ministry Project to Promote Standardized Healthcare Information Exchange

Objectives: To promote healthcare information exchange between providers and to allow hospital information systems (HIS) export information in standardized format (HL7 and DICOM) in an environment of widespread legacy systems, which only can export data in proprietary format.

Methods: Through the Shizuoka prefecture EMR project in 2004–2005, followed by the ministry’s SS-MIX project, many software products have been provided, which consist of 1) a standardized storage to receive HL7 v2.5 mes sages of patient demographics, prescription orders, laboratory results, and diagnostic disease in ICD-10, 2) a referral letter creation system, 3) a formatted document creation system, 4) a progress note/nursing record system, and 5) an archive/viewer to incorporate incoming healthcare data CD and allow users to view on HIS terminal. Meanwhile, other useful applications have been produced, such as adverse event reporting and clinical information retrieval. To achieve the above-mentioned objectives, these software products were created and propagated, because users can use these software products, provided that their HIS can export the above information to the standardized storage in HL7 v2.5 format.

Results: In 20 hospitals of Japan, the standardized storage has been installed and some applications have been used. As major HIS vendors are shipping HIS with HL7 export function since 2007, HIS of 594 hospitals in Japan became capable of exporting data in HL7 v2.5 format (as of March 2010).

Conclusions: In high CPOE installation rate (85% in 400+ bed hospitals), though most of them only capable of exporting data in proprietary format, prefecture and ministry projects were effective to promote healthcare information exchange between providers. The standardized storage became an infrastructure for many useful applications, and many hospitals started using them. Ministry designation of proposed healthcare standards was effective so as to allow vendors to conform their products, and users to install them.

Postnatal changes in ghrelin mRNA expression and in ghrelin-producing cells in the rat stomach

Ghrelin was recently isolated from the rat stomach as an endogenous ligand for the GH secretagogue receptor. Although it is well known that a large amount of ghrelin is produced in the gastrointestinal tract, developmental changes in ghrelin mRNA expression and differentiation of ghrelin-immunopositive (ghrelin-ip) and mRNA-expressing (ghrelin-ex) cells in the stomach have not been elucidated. In this study, we therefore investigated the changes in ghrelin mRNA expression levels and in the numbers of ghrelin-ip and -ex cells in the stomachs of 1- to 8-week-old male and female rats by Northern blot analysis, immunohistochemistry and in situ hybridization. Northern blot analysis showed that the level of weak ghrelin mRNA expression was low in the postnatal period but then increased in a dimorphic pattern, i.e. transient stagnation at 4 weeks in the male rats and at 5 weeks in the female rats. The number of ghrelin-ip and ghrelin-ex cells also increased after birth, and more numerous ghrelin cells were found in female rats than in male rats, and this finding was confirmed by Northern blot analysis. Ghrelin-ip and -ex cells first appeared in the glandular base of the fundic gland and then they were found in the glandular base and the glandular neck at 3 weeks of age, suggesting that the distribution of ghrelin cells is extended from the glandular base to the glandular neck during the postneonatal development period. This is the first report on detailed changes in postneonatal ghrelin expression level and in the number of ghrelin cells in the rat stomach. The sexual dimorphism of ghrelin expression and ghrelin cell differentiation suggest that ghrelin plays an important physiological role in the stomach.

Uncertain Eigenvalue Analysis of Composite Laminated Plates by the Stochastic Finite Element Method

Uncertain eigenvalue problem of linear vibration is analyzed by means of the stochastic finite element method, the basis of which utilizes mean-centered second order perturbation technique. Attention is paid to the fluctuation of the stacking sequence, that is, fiber orientation and layer thickness of FRP laminated plates. The stacking sequence is expressed in terms of probabilistic variables. The eigenvalue problem is formulated based on the Kirchhoff-Love’s theory of thin plate, the stretching, coupled and bending stiffnesses of which are uncertain due to the stacking sequence. The numerical analyses deal with the vibration of simply-supported graphite/epoxy plates. The sensitivity of the input stacking sequence and the correlation coefficients of the probabilistic variables are evaluated quantitatively.

Erythromycin improves glycaemic control in patients with Type II diabetes mellitus

AIMS/HYPOTHESIS

Erythromycin mimics the effect of the gastrointestinal hormone motilin by binding to its receptor and acting as a motilin agonist. We recently found that motilin stimulates insulin secretion at lower doses than doses required to stimulate gastric contractile activity. We studied the effects of erythromycin on insulin secretion and glycaemic control in patients with diabetes mellitus.

METHODS

Inpatients (n = 34) with Type II (non-insulin-dependent) diabetes mellitus were randomly assigned to receive either erythromycin (400 mg orally three times a day, n = 19) or a placebo (n = 15) for 1 week (first study). Another 34 outpatients with Type II diabetes were also treated with erythromycin (200 mg orally three times a day, n = 17) or a placebo (n = 17) for 4 weeks (second study). Finally, nine inpatients with Type II diabetes and eight normal control subjects received intravenous erythromycin (10 mg x kg(-1) x h(-1)) or saline infusion and insulin secretion was examined (third study).

RESULTS

Erythromycin lowered fasting blood glucose and fructosamine concentrations (p < 0.01) and increased basal as well as glucose-stimulated insulin secretion (p <0.05-0.01) (first study). Low doses of erythromycin treatment for 4 weeks also significantly improved glycaemic control in Type II diabetic patients (second study). Erythromycin infusion significantly increased plasma insulin and decreased glucose concentrations in Type II diabetic and control subjects and greatly potentiated glucose-induced insulin secretion in the latter (third study).

CONCLUSION/INTERPRETATION

These results indicate that erythromycin given orally has an antidiabetogenic effect and therefore erythromycin derivatives that lack the antibacterial activity could have a therapeutic value in Type II diabetic patients.

Serum amyloid P component is the Shiga toxin 2-neutralizing factor in human blood

It has been suggested that some factor present in human plasma binds to Shiga toxin 2 (Stx2) and neutralizes it in vitro (Bitzan, M., Klemt, M., Steffens, R., and Muller-Wiefel, D. E. (1993) Infection 21, 140-145). This factor does not exist in other species (Caprioli, A., Luzzi, I., Seganti, L., Marchetti, M., Karmali, M., Clarke, I., and Boyd, B. (1994) Recent Adv. VTEC Infect. 353-356). Because analysis of this factor is important to understanding the pathology induced by Shiga toxin-producing Escherichia coli, we purified this factor from human plasma and identified it. Purification was carried out by serially subjecting human plasma to Con A-Sepharose, DEAE-Sepharose, hydroxyapatite, and gel-filtration high performance liquid chromatography (HPLC), using Stx2-neutralizing activity as the indicator. The gel-filtration HPLC fraction yielded a single band on SDS-polyacrylamide gel electrophoresis. Twenty N-terminal amino acid residues of this fraction were analyzed and found to correspond perfectly to human serum amyloid P component (HuSAP). Because commercially available HuSAP also showed Stx2 binding and neutralizing activity, we identified this factor as HuSAP.

Background values for evaluation of heavy metal contamination in sediments

The contamination of sediments can be evaluated from comparison of the current concentration with the estimated background value. Although it is known that grain size affects background concentrations, there have been difficulties in evaluating this effect. The specific surface area of sediments, which can be calculated from the grain size distribution, is introduced as a property index for correlation of background values. The results show that for sandy-to-sandy silt sediments, the background values of metals are expressed in terms of fines content, which can be correlated with the corresponding specific surface area. However, for silty clay or clayey silt sediments, which would have a high metal retention capacity, the level of the background may be constrained by the relatively low concentrations of metals in seawater. Finally, background levels of Zn, Cu and Pb are presented.

APC2 plays an essential role in axonal projections through the regulation of microtubule stability

Growth cones at the tip of growing axons are key cellular structures that detect guidance cues and mediate axonal growth. An increasing number of studies have suggested that the dynamic regulation of microtubules in the growth cone plays an essential role in growth cone steering. The dynamic properties of microtubules are considered to be regulated by variegated cellular factors but, in particular, through microtubule-interacting proteins. Here, we examined the functional role of adenomatous polyposis coli-like molecule 2 (APC2) in the development of axonal projections by using the chick retinotectal topographic projection system. APC2 is preferentially expressed in the nervous system from early developmental stages through to adulthood. Immunohistochemical analysis revealed that APC2 is distributed along microtubules in growth cones as well as axon shafts of retinal axons. Overexpression of APC2 in cultured cells induced the stabilization of microtubules, whereas the knockdown of APC2 in chick retinas with specific short hairpin RNA reduced the stability of microtubules in retinal axons. APC2 knockdown retinal axons showed abnormal growth attributable to a reduced response to ephrin-A2 in vitro. Furthermore, they showed drastic alterations in retinotectal projections without making clear target zones in the tectum in vivo. These results suggest that APC2 plays a critical role in the development of the nervous system through the regulation of microtubule stability.

Histologic and biochemical alterations in experimental acute pancreatitis induced by supramaximal caerulein stimulation

We studied the histologic and biochemical alterations in experimental acute pancreatitis induced by supramaximal caerulein stimulation in rats. All rats received 4 subcutaneous injections of various doses of caerulein (5-50 micrograms/kg body weight) at hourly intervals over 3 h, and 9 h after the first injection all animals were killed. Subcutaneous injections of 20 micrograms/kg body weight of caerulein induced a significant increase in serum amylase activity and histologic evidence of acute interstitial pancreatitis similar to those observed with the 50 micrograms/kg body weight dosage of caerulein. Therefore, a total of 4 subcutaneous injections of 20 micrograms/kg body weight of caerulein was chosen to study the time-course of structural and biochemical alterations in caerulein-induced acute pancreatitis. Serum amylase activity reached a maximal value of 10-fold increase over the basal values at 6 h, and then decreased gradually to normal values at 18 h after the first injection. Remarkable interstitial edema and cytoplasmic vacuoles in acinar cells were the earliest histologic alterations. Cellular infiltration was prominent at 9-12 h after the first injection. Although these histologic changes almost completely disappeared after 24 h, the reduction in the number of zymogen granules was still detectable by electron microscopic examination even after 7 days. DNA content in the pancreas showed no significant changes following the induction of acute pancreatitis, whereas a moderate to marked reduction in enzyme content persisted after 7 days. Within 14 days after the initiation of the injections, both structural and biochemical changes had completely disappeared.

Antitumor agents. 78. Inhibition of human DNA topoisomerase II by podophyllotoxin and alpha-peltatin analogues

It has been reported that the action of etoposide (VP-16) (14) as an antitumor agent is mediated through its interaction with DNA topoisomerase II which results in DNA breakage inside the cell. In order to understand the mechanism of action as well as structure-activity relationships of 14, several novel, synthetic and some naturally occurring analogues related to podophyllotoxin were examined for inhibition of the DNA topoisomerase II activity. Compound 2 exhibited enhanced activity and compound 5 slightly diminished activity relative to 14. A 4 beta-substituted ether at the C ring and O-demethylation at the E ring appear to enhance activity.

High incidence of autoimmune gastritis in patients misdiagnosed with two or more failures of H. pylori eradication

BACKGROUND

Although autoimmune gastritis (AIG) is generally considered relatively rare, we frequently encounter AIG among patients at to our hospital who have experienced at least two episodes of Helicobacter pylori eradication failure.

AIMS

We investigated the incidence of AIG in consecutive patients who consulted our department for H. pylori eradication with reference to eradication history.

METHODS

A total of 404 consecutive patients who visited the H. pylori-specific out-patient unit of our hospital from June 2015 to June 2017 were enrolled. Of these, 137 were treatment-naive, 47 had failed treatment once (single failure), and 220 had failed treatment twice or more (multiple failures) by 13 C-UBT. Gastroscopy was performed in all patients. Culture tests of gastric mucosal samples were performed for H. pylori and other bacteria positive for urease activity. Anti-parietal cell antibody (APCA) was measured. Patients with severe atrophy in the gastric corpus and positivity for APCA were diagnosed as having AIG.

RESULTS

A total of 43 patients were diagnosed as having AIG, of whom two were treatment-naive (1.5%, 2/137), 1 failed eradication once (2.1% 1/47), and 40 failed treatment at least twice (18.2%, 40/220). The incidence of AIG was significantly higher in the multiple failure group than in the single failure or treatment-naive groups. Urease-positive bacteria, such as Klebsiella pneumoniae and alpha-streptococcus, were identified in 33 of the 35 AIG patients who underwent culture testing.

CONCLUSION

AIG patients were often misdiagnosed as refractory to eradication therapy, probably because achlorhydria in AIG might allow urease-positive bacteria other than H. pylori to colonise the stomach, causing positive 13 C-UBT results.