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H Futami

Publications and source records attributed to H Futami.

At least 19 recordsLinked to original sources
PubMed2000

A two-hit model for development of multiple endocrine neoplasia type 2B by RET mutations.

Multiple endocrine neoplasia (MEN) type 2B mutations have been reported at methionine 918 or alanine 883 in the tyrosine kinase domain of the RET proto-oncogene. Recently, a new combination of two germline missense mutations at valine 804 and tyrosine 806 was identified in a patient with MEN 2B-like clinical phenotypes including medullary thyroid carcinoma, mucosal neuroma, and marfanoid habitus. In this case, valine 804 and tyrosine 806 were replaced with methionine and cysteine, respectively. In the present study, biological activities of RET with these new mutations were compared with those with known MEN 2A or MEN 2B mutations. The transforming activity of RET with the V804M/Y806C mutation was about 8- to 13-fold higher than that of RET with a single V804M or Y806C mutation. Like RET with the M918T or A883F MEN 2B mutation, the transforming activity of RET with the V804M/Y806C mutation was not affected by substitution of phenylalanine for tyrosine 905 that abolished the activity of RET with the MEN 2A mutation. On the other hand, substitution of phenylalanine for tyrosines 864 and 952 drastically diminished the activity of RET with the V804M/Y806C, M918T or A883F mutation, suggesting that these three mutant proteins have similar biological properties.

3T3 Cells↗
PubMed2000

Unilateral surgery supported by germline RET oncogene mutation analysis in patients with sporadic medullary thyroid carcinoma.

Compared to hereditary medullary thyroid carcinoma (MTC), sporadic MTC tends to be unicentric and confined to one lobe. Patients with sporadic MTC usually undergo total thyroidectomy because of a possible hereditary or bilateral process. We evaluated the usefulness of germline RET oncogene mutation analysis in surgery for apparently sporadic MTC and performed unilateral surgery on patients without detectable mutation. In 36 patients with a preoperative diagnosis of apparently sporadic MTC, we performed germline RET oncogene mutation analyses: before surgery in 8 recent patients and after surgery in 28 who had been treated before 1996. Of the latter, 5 had bilateral MTC. DNA samples were extracted from their peripheral blood, and the polymerase chain reaction products of the RET proto-oncogene were analyzed using single-strand conformation polymorphism analysis and the direct sequencing methods. Before 1996 we often performed total thyroidectomy but changed to hemithyroidectomy thereafter, except in one patient with associated Graves' ophthalmopathy. Our minimal standard practice included systematic central and ipsilateral neck dissection. The outcome was assessed in terms of gastrin- and calcium-stimulated plasma calcitonin levels. Germline RET mutations were found in six patients. Five of these patients had bilateral MTC, whereas all 30 patients without mutation had unilateral disease. Hemithyroidectomy in seven of our recent patients resulted in normalization of plasma calcitonin levels in all, although four were found to have microscopic lymph node involvement. In conclusion, hemithyroidectomy with systematic central and ipsilateral neck dissection is an appropriate procedure for patients with sporadic MTC without detectable germline RET mutations.

Adult↗
PubMed1999

Relationship between Helicobacter pylori infection and gastric metaplasia in the duodenal bulb in the pathogenesis of duodenal ulcer.

BACKGROUND: The aim of this study was to determine whether the amount of Helicobacter pylori and the extent of gastric metaplasia in the duodenal mucosa play critical roles in the pathogenesis of duodenal ulcer. METHODS: Duodenal and gastric biopsy specimens were obtained from H. pylori-positive patients with duodenal ulcer, gastric ulcer or chronic gastritis. The extent of gastric metaplasia was evaluated histologically and endoscopically using the methylene blue test. In this study, we performed competitive polymerase chain reaction, a highly sensitive and quantitative method for determining the amount of H. pylori gastric and duodenal mucosa. The prevalence and extent of gastric metaplasia and the amount of H. pylori in the duodenal bulb in the three patient groups were compared. The correlation between the amount of H. pylori in the duodenum and gastric antrum and extent of gastric metaplasia were also determined. RESULTS: The prevalence and extent of gastric metaplasia and the amount of H. pylori in the duodenal bulb in patients with duodenal ulcer were much higher than in patients with gastric ulcer or chronic gastritis. A positive correlation was found between the amount of H. pylori in the duodenum and the extent of gastric bulb and that in the antrum. CONCLUSIONS: The findings of this study indicate that H. pylori colonization in the duodenal bulb may play a critically important role in the pathogenesis of duodenal ulcer and that the amount of H. pylori in the duodenal bulb may be related to the amount of H. pylori in the gastric antrum and the extent of gastric metaplasia in the duodenal bulb.

Adult↗
PubMed1999

H+/K+-adenosine triphosphatase mRNA in gastric fundic gland mucosa in patients infected with Helicobacter pylori.

BACKGROUND: How Helicobacter pylori infection affects gastric acid secretion has not been made clear. This study aimed to elucidate the effects of H. pylori infection on H+/K+-adenosine triphosphatase (ATPase) mRNA in gastric fundic gland mucosa. METHODS: Twenty patients with chronic gastritis and H. pylori infection were treated with lansoprazole and antibiotics. Before and 1 month after treatment gastroduodenoscopy was performed, and changes in the amount of H+/K+-ATPase mRNA in the fundic gland mucosa, gastric juice pH, and serum gastrin levels were determined. RESULTS: The amount of H+/ K+-ATPase mRNA in the fundic gland mucosa was increased in patients with eradication of H. pylori, in whom significant decreases in gastric juice pH and serum gastrin levels were observed. No significant changes were observed in patients without eradication of H. pylori. CONCLUSIONS: These results suggest that one of the mechanisms by which H. pylori infection suppresses acid secretion is by the inhibition of proton pump synthesis in parietal cells.

DNA Primers↗
PubMed1999

Two germline missense mutations at codons 804 and 806 of the RET proto-oncogene in the same allele in a patient with multiple endocrine neoplasia type 2B without codon 918 mutation.

Multiple endocrine neoplasia (MEN) type 2B is a clinically distinct entity among the autosomal dominant MEN 2 syndromes. Most patients with MEN 2B carry a germline mutation (M918T) of the RET proto-oncogene, while a few carry A883F. We examined a patient with MEN 2B, but without M918T or A883F, and her relatives. Here, we report the presence in this patient of 2 germline mutations, V804M and Y806C in the same allele. While the novel Y806C was inherited from her father, its carriers (her father and brother) was not affected by MEN 2. In contrast, V804M was a de novo mutation, that has been reported in patients with familial medullary thyroid carcinoma. Combinations of mutations of the RET proto-oncogene may cause oncogenic activities different from those of single mutations.

Base Sequence↗
PubMed1999

Further evidence that exacerbation of ulcerative colitis causes the onset of immune thrombocytopenia: a clinical case.

Ulcerative colitis associated with immune-mediated thrombocytopenia is rare. It has been suggested that antigenic mimicry between platelet surface antigen and bacterial glycoprotein plays a role in this association. We present a case in which exacerbation of UC sequentially induced development of ITP associated with elevation of PAIgG. In the case, two episodes of ITP occurred, with each preceded by exacerbation of UC. After remission of UC, ITP remitted and PAIgG simultaneously decreased. In the first episode, the onset of ITP was about 1 month after the exacerbation of UC. However, in the second episode, the onset of ITP was much faster, 11 days after that of UC, and the magnitude of elevation of PAIgG was much higher in the second episode. This may provide further evidence that ITP is causally associated with UC, and is the result of immunostimulation from luminal antigens and altered immunoregulation.

Adult↗
PubMed1999

Relation between interleukin-1beta messenger RNA in gastric fundic mucosa and gastric juice pH in patients infected with Helicobacter pylori.

The effects of Helicobacter pylori infection on gastric acid secretion has not been clarified. The aim of this study was to elucidate the effects of H. pylori infection on gastric juice pH in relation to gene expression of interleukin-1beta (IL-1beta), which is reported to inhibit gastric acid secretion. Gastric juice pH and serum gastrin levels were measured in patients with peptic ulcer disease. The amount of IL-1beta mRNA in gastric fundic gland mucosa was also measured by a competitive reverse transcription-polymerase chain reaction method. These parameters were determined before and after treatment with lansoprazole and amoxicillin. Before treatment a significant positive relation was observed between the amount of IL-1beta mRNA in gastric fundic gland mucosa and gastric juice pH. After treatment significant decreases in the amount of IL-1beta mRNA, gastric juice pH, and serum gastrin levels were observed in patients with eradication of H. pylori, whereas no significant changes were observed in patients without eradication. These results suggest that H. pylori infection induces IL-1beta and suppresses acid secretion, resulting in increases in gastric juice pH and serum gastrin levels. Eradication of H. pylori decreases IL-1beta induction, resulting in an increase in gastric juice acidity and normalization of serum gastrin levels.

Base Sequence↗
PubMed1998

Pyoderma gangrenosum complicating ulcerative colitis: Successful treatment with methylprednisolone pulse therapy and cyclosporine.

A 32-year-old woman with ulcerative colitis had a relapsed of pyoderma gangrenosum during puerperium. Both the pyoderma gangrenosum and ulcerative colitis had been well controlled with oral prednisolone, but ulcerative colitis relapsed in pregnancy, and pyoderma gangrenosum relapsed in the puerperium. The pyoderma gangrenosum responded to methylprednisolone pulse therapy initially, but relapsed when prednisolone was tapered. A second trial of pulse therapy combined with cyclosporine resulted in complete remission of the pyoderma gangrenosum, and no recurrence was recognized after prednisolone was tapered. This is a very rare case of successful treatment with methylprednisolone pulse therapy combined with cyclosporine for pyoderma gangrenosum complicating ulcerative colitis.

Adult↗
PubMed1998

Effect of Helicobacter pylori infection on gastric juice pH.

BACKGROUND: How Helicobacter pylori infection affects gastric acid secretion is still unclear. METHODS: Gastric juice pH, ammonia concentration in gastric juice, serum gastrin level, and grade of gastritis in accordance with the Sydney System were determined for patients with gastric ulcer (GU) and duodenal ulcer (DU) before and after treatment with lansoprazole and amoxicillin, and results were compared with those of H. pylori-negative controls. RESULTS: Scores for H. pylori density, atrophy, metaplasia, and activity of gastritis in the corpus were higher in patients with GU, especially those with proximally located GU, than in those with DU. Gastric juice pH was significantly higher in GU patients than in DU patients and controls. After H. pylori eradication, gastric juice pH and serum gastrin levels in both GU and DU patients were significantly decreased to control levels. In patients without eradication, no significant changes in these factors were observed. CONCLUSIONS: These findings suggest that H. pylori infection and gastritis in the corpus suppress acid secretion and increase gastric juice pH, resulting in hypergastrinemia, and that eradication of H. pylori normalizes acid secretion and serum gastrin levels.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1998

Genotype-phenotype correlation of patients with multiple endocrine neoplasia type 2 in Japan.

BACKGROUND: Multiple endocrine neoplasia type 2 (MEN 2) is a hereditary syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma and hyperparathyroidism. MEN 2 is caused predominantly by germ-line mutations of the RET proto-oncogene. This study aimed to clarify the genotype-phenotype correlation in MEN 2 patients in Japan in order to modify the clinical management according to the genotype. METHODS: Constitutive DNA of 64 MEN 2 patients (48 kindreds) were searched for mutations at exons 10, 11, 13, 14 and 16 of the RET proto-oncogene using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), direct sequencing and restriction enzyme digestion. The clinical characteristics of the patients were obtained from a previous nationwide questionnaire survey. RESULTS: Overall, 62 (96.9%) out of 64 patients had a germ-line point mutation at the hot spots. MTC and pheochromocytoma occurred equally in every genotype except C630S. Specific genotype had a correlation between tumor size and age at the operation for MTC or extent of MTC, i.e. C618S developed late onset type of MTC as compared with that of C634R, C634Y and M918T. Small MTC in C634R may be less aggressive than those in C634Y and M918T. CONCLUSIONS: DNA testing has good clinical implications for the management of patients with MEN 2 and the timing and operative procedures of thyroidectomy can be modified according to the genotype.

Adrenal Gland Neoplasms↗
PubMed1998

A large germline deletion of the MEN1 gene in a family with multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN1) is a familial cancer syndrome inherited as an autosomal dominant trait. Various heterozygous germline mutations of the responsible gene, MEN1, have been identified within its exons in many, but not all, affected individuals. We here demonstrate, by DNA polymorphism analysis and gene dosage analysis with polymerase chain reaction (PCR), a large heterozygous germline MEN1 deletion in a kindred with MEN1, in whom no mutation could be detected in the PCR-amplified exons. The deletion spanned an at least 7 kb region containing the entire MEN1 gene. These findings indicate that a large germline deletion of the MEN1 gene, which escapes detection in PCR-based sequence analysis, should be considered as a potential cause of MEN1.

Chromosome Deletion↗
PubMed1998

Amount of Helicobacter pylori in gastric mucus during anti-H. pylori treatment.

Helicobacter pylori is present in infected patients not only on the gastric epithelial cell surface but also in gastric mucus. We developed a competitive polymerase chain reaction (cPCR) method for quantitative measurement of H. pylori in gastric mucus. The aim of this study was to determine the number of H. pylori in gastric mucus before and after anti-H. pylori treatment. Patients with duodenal ulcer were treated with lansoprazole alone (n = 11) or lansoprazole and amoxycillin (n = 12). The amount of H. pylori in gastric mucus was measured over time by a cPCR assay. Helicobacter pylori infection was also tested for using histology, culture, and the rapid urease test (RUT). Although most patients treated with lansoprazole alone had become H. pylori-negative by the end of treatment when tested by histology, RUT, and culture, a large number of H. pylori organisms were found in the gastric mucus at that time by cPCR. These patients returned to being H. pylori positive 1 to 12 months later on the basis of histology, RUT, and culture. However, cPCR results indicated eradication of H. pylori by the end of treatment in eight of the 12 patients treated with lansoprazole and amoxicillin, and these patients remained H. pylori negative on histology, RUT, culture, and cPCR 1 to 12 months later. Testing for H. pylori in gastric mucus is thus useful for precise determination of the success or failure of H. pylori eradication therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1997

Adenoma of the common human bile duct in Gardner's syndrome may cause relapsing acute pancreatitis.

Familial adenomatous polyposis of the colon, or Gardner's syndrome, is often accompanied by adenomas of the stomach and duodenum. We experienced a rare case of Gardner's syndrome, with adenomas of the common bile duct, in a patient who presented with relapsing acute pancreatitis. Our findings indicate that adenoma in the common bile duct or pancreatic duct should be considered as a possible etiology when patients with familial polyposis or Gardner's syndrome present with pancreatitis, particularly relapsing acute pancreatitis.

Adenoma↗
PubMed1997

Germline mutations of the MEN1 gene in Japanese kindred with multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant familial cancer syndrome. The responsible gene MEN1 has recently been isolated, and its germline mutations have been identified in affected individuals in the United States, Canada and Europe. We screened for MEN1 mutations by direct nucleotide sequencing of all protein-coding regions, and identified five distinct germline mutations in five among six Japanese kindreds with familial MEN1 or familial hyperparathyroidism. The mutations were dispersed across the gene. These findings suggest that, because of the absence of an obvious founder effect, the entire MEN1 gene region should be examined for germline mutations in the probands of MEN1 and related syndromes in Japanese families.

DNA, Neoplasm↗
PubMed1997

A novel somatic mutation in the RET proto-oncogene in familial medullary thyroid carcinoma with a germline codon 768 mutation.

In individuals who carry germline mutations in tumor suppressor genes predisposing them to inherited cancer syndromes, occurrence of somatic mutations in the same genes contributes to tumorigenesis. Germline mutations in the RET proto-oncogene predispose individuals to multiple endocrine neoplasia (MEN) type 2 syndromes. Since these mutations are oncogenic by themselves, somatic mutations in the same gene had been thought unnecessary. Recently, a somatic mutation at codon 918 of RET was reported in medullary thyroid carcinoma (MTC) and C-cell hyperplasia in patients with MEN 2A or familial MTC (FMTC), suggesting its possible contribution to tumorigenesis. We describe here a novel somatic mutation at codon 919 in a patient with FMTC carrying a germline mutation at codon 768 that may also be related to tumor progression.

Aged↗
PubMed1997

Study of transmission routes of Helicobacter pylori in relation to seroprevalence of hepatitis A virus.

The seroprevalence of Helicobacter pylori in a group of 1,043 healthy Japanese people was compared with that of hepatitis A virus (HAV), which was used as a marker of fecal-oral exposure. No statistically significant relationship was observed between seropositivity for HAV and that for H. pylori. Therefore, the fecal-oral spread of H. pylori is of limited relevance in Japan.

Helicobacter Infections↗