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K Yamao

Publications and source records attributed to K Yamao.

At least 19 recordsLinked to original sources
PubMed2006

Systematic review and meta-analysis: importance of CagA status for successful eradication of Helicobacter pylori infection.

BACKGROUND: Some, but not all studies have provided evidence that the CagA status of Helicobacter pylori strains is a predictive factor for the outcome of eradication therapy. AIM: To clarify the association between CagA status and eradication outcome. METHODS: We included studies reporting the numbers of successful and failed cases in H. pylori-eradication therapy according to the CagA status. Fourteen studies (1529 patients) were included of 325 articles identified in the search. The pooled risk ratio for H. pylori-eradication failure in CagA-negative relative to CagA-positive strains and the pooled risk difference in eradication success between the two groups were used as summary statistics. Meta-regression was used for examining the source of heterogeneity. RESULTS: The summary risk ratio for eradication failure in CagA-negative relative to CagA-positive was 2.0 (95% CI: 1.6-2.4, P < 0.001), corresponding with the summary risk difference for eradication success between the groups of 11% (95% CI: 3-19%, P = 0.011). Meta-regression analysis demonstrated that usage of polymerase chain reaction examination for CagA status and a high proportion of non-ulcer dyspepsia patients were factors for heterogeneity among studies. CONCLUSIONS: Our meta-analysis confirmed the importance of the presence of CagA as a predictor for successful eradication of H. pylori.

Antigens, Bacterial↗
PubMed2006

Influence of smoking and CYP2C19 genotypes on H. pylori eradication success.

CYP2C19 polymorphisms and smoking influence the efficacy of H. pylori eradication therapy, but interaction between the two have hitherto not been examined. A total of 142 H. pylori-positive patients who received triple drug therapy with lansoprazole, amoxicillin and clarithromycin were categorized into three groups with regard to diplotypes of CYP2C19: homozygous extensive metabolizer (homEM), heterozygous EM (hetEM), and poor metabolizer (PM). The overall success rate was 61.3%. Smoking was an independent risk factor of eradication failure (OR 2.81, 95% CI 1.14-6.91), whereas CYP2C19 polymorphisms were less influential. Among non-smokers, the homEM and hetEM groups showed worse eradication rates (58.5 and 67.3%) relative to PM (76.2%) as expected; however, an opposite trend was observed among smokers (homEM 50.0%, hetEM 46.7%, PM 20.0%), indicating possible interactions with CYP2C19 polymorphisms. Smoking has a greater influence on H. pylori eradication than the CYP2C19 genotype. Interaction between smoking and CYP2C19 should be examined in the future.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2006

Indocyanine green is an ideal dye for endoscopic ultrasound-guided fine-needle tattooing of pancreatic tumors.

Endoscopic ultrasound-guided fine-needle tattooing (EUS-FNT) is an ideal technique for preoperative marking of lesions detected on preoperative examination. Although India ink has been used for endoscopic tattooing, there have been numerous reports of complications associated with its use. This is the first report of EUS-FNT using indocyanine green (ICG) and describes its use for preoperative marking of a tumor in a 78-year-old man with multiple pancreatic tumors. There were no complications associated with the EUS-FNT procedure and it is suggested that ICG is a more suitable dye for tattooing of pancreatic lesions than India ink, being far less frequently associated with side effects.

Aged↗
PubMed2005

Puncture of solid pancreatic tumors guided by endoscopic ultrasonography: a pilot study series comparing Trucut and 19-gauge and 22-gauge aspiration needles.

BACKGROUND AND STUDY AIMS: The aim of this prospective study was to compare endoscopic ultrasonography-guided Trucut needle biopsy (EUS-TNB) with EUS-guided fine-needle aspiration biopsy (EUS-FNAB) using 19- and 22-gauge needles for biopsy from different sites in patients with solid pancreatic cancers. PATIENTS AND METHODS: Sixteen consecutive patients with masses in the uncinate process (n = 3), the head (n = 5), or the body and tail (n = 8) of the pancreas underwent both EUS-TNB and EUS-FNAB. The specimens obtained were evaluated by histopathological analysis alone RESULTS: Tissue specimens were obtained by Trucut needle, and by 19-gauge and 22-gauge aspiration needles in 69 %, 69 %, and 100 % of patients respectively. Sensitivity for malignancy was 69 % for all needles. Tissue sampling by Trucut and by 19-gauge aspiration needle from masses in the uncinate process was impossible. The sensitivity of the Trucut and 19-gauge aspiration needles was 100 % in the 11 patients with successful procedures. If Trucut or 19-gauge aspiration needles had been used for body and tail masses, and the 22-gauge aspiration needle for masses in the uncinate process and head, the sensitivity for malignancy would have been 81 %. CONCLUSIONS: EUS-TNB allows reliable tissue sampling for the diagnosis of pancreatic masses, but its use is limited to lesions in the body and tail of the pancreas. EUS-FNAB using a 22-gauge needle may be useful for accurate diagnosis in some patients with masses in the uncinate process or the head of the pancreas.

Aged↗
PubMed2001

Peripheral T/natural killer-cell lymphoma involving the female genital tract: a clinicopathologic study of 5 cases.

Malignant lymphoma of the female genital tract (FGT) is rare. In this study, 5 peripheral T/natural killer (NK)-cell lymphomas (PTCLs) involving the FGT are reported. They include 2 from the uterus and 1 each from ovary, uterus and ovary, and vagina, and were detected between 1996 and 2000. One of the 2 ovarian tumors was bilateral. In all cases, the FGT was the initial site of clinical presentation of disease. Age at presentation ranged from 21 to 52 years (median, 36 years). One case was stage I disease, 2 were stage II, and 2 were stage IV. All 5 tumors were positive for CD3epsilon, and 3 harbored the Epstein-Barr virus, although the detailed immunophenotypic profiles varied. Three were diagnosed as nasal type T/NK-cell lymphoma, 1 as anaplastic large-cell lymphoma (anaplastic lymphoma kinase [ALK]-positive), and 1 as unspecified PTCL of cytotoxic phenotype, according to the forthcoming World Health Organization classification. Four of 5 patients received laparotomy and chemotherapy. Four patients (in stages II and IV) died of disease within 16 months of the initial diagnosis, whereas only 1 patient (in stage I) is alive without disease at 39 months of follow-up. Our experience in this series provided clinically relevant information on diagnosis, treatment, and outcome for extremely rare tumors of the FGT.

Adult↗
PubMed2001

Epithelial inclusion cyst (epidermoid cyst) formation with epithelioid cell granuloma in an intrapancreatic accessory spleen.

The histologic characteristics of a case of epidermoid cyst formation with an epithelioid cell granuloma that developed in intrapancreatic accessory spleen were investigated, with the aim of clarifying its origin as well as etiologic factors. The patient, a 48-year-old male, was found to have a cystic lesion in the tail of the pancreas and renal cell carcinoma (clear cell carcinoma) during a medical check up. The pancreatic mass appeared to be a so-called "mucinous tumor" on imaging, and combined resection of the body and tail of the pancreas and the spleen was performed together with a left nephrectomy. The lesion in the tail of the pancreas was then demonstrated to have accessory splenic tissue with cyst formation in its central region. The cystic wall was covered with stratified squamous epithelium and ductal epithelium with squamous metaplasia, and pancreatic islet cells were evident at various sites within the accessory spleen. Formation of epithelioid cell granuloma tissue was observed around the cysts. The epithelium of the cyst was positive for CA19-9 and negative for antibodies against mesothelial cells, whereas the pancreatic island cells were positive for insulin. These results suggested that cystic epithelium in the accessory spleen could be derived from pancreatic duct epithelium. Frequent recurrence of chronic inflammation and epitheloid cell granuloma formation may have resulted from an aberration of the ectopic remaining pancreatic tissue in the spleen.

Choristoma↗
PubMed2001

Interleukin 1 polymorphisms, lifestyle factors, and Helicobacter pylori infection.

Associations between Helicobacter pylori (HP) infection and lifestyle factors have been reported by several authors, but little is known about the host factors associated with the infection. This study aims to examine the infection rate of HP according to gene polymorphisms of interleukin (IL)-1A, IL-1B, and IL-1RN, and to investigate the interactions with lifestyle factors. Subjects were 241 non-cancer outpatients who had participated in a HP eradication program. Polymorphisms at - 889 (T to C) of IL-1A, at - 31 (C to T; T allele makes a TATA box) and - 511 (C to T) of IL-1B, and at intron 2 (86-bp VNTR (variable number of tandem repeats)) of IL-1RN were genotyped by PCR (polymerase chain reaction), PCR-RFLP (restriction fragment length polymorphism) and PCR-CTPP (PCR with confronting two-pair primers). It was found that IL-1B polymorphisms at - 31 and - 511 were near-completely linked, but in the opposite way to that in Caucasians; - 31C / - 511T and - 31T / - 511C alleles were dominant in the present subjects. The HP infection rate was substantially different among the genotypes of IL-1B C - 31T; 45.2% (19 / 42) for the C / C, 67.7% (90 / 133) for the C / T, and 63.6% (42 / 66) for the T / T. The age-sex adjusted odds ratio (OR) relative to the C / C genotype was 2.32 (95%CI (confidence interval), 1.10 - 4.92) for the T / C genotype and 2.46 (1.06 - 5.74) for the T / T genotype. The OR for the T / T genotype was significantly modified by smoking status; interaction term = 14.6 (1.12 - 190). The polymorphisms of IL-1A and IL-1RN were not associated with the infection rate. The results suggested that the T allele of IL-1B C - 31T is associated with vulnerability to persistent HP infection, and that the vulnerability is modified by smoking.

Adult↗
PubMed2000

Transpapillary biopsy in gallbladder disease.

BACKGROUND: Endoscopic biopsy is routine in gastrointestinal disease; similarly, histopathologic diagnosis is desirable in gallbladder disease. In this study we examined the clinical usefulness and the problems associated with transpapillary gallbladder biopsy. METHODS: Transpapillary gallbladder biopsy was attempted in 9 patients with gallbladder disease. After inserting a catheter sheath into the gallbladder using a guidewire via the transpapillary route without sphincterotomy, we inserted a biopsy forceps into the lumen of the sheath up to the gallbladder lumen and obtained specimens. RESULTS: We could obtain sufficient specimens for histopathologic diagnosis in 8 of 9 cases (88.9%). Of the 8 successful cases, targeted specimens were obtained in 7 (87.5%). Diagnostic accuracy with respect to malignant versus benign disease was 100% (2 of 2) and 83.3% (5 of 6), respectively. There were no complications. CONCLUSION: Transpapillary gallbladder biopsy is a clinically useful technique because it facilitates histopathologic diagnosis and therefore guides the choice of therapy.

Biopsy↗
PubMed2000

Methylation status of the p15INK4B gene in hematopoietic progenitors and peripheral blood cells in myelodysplastic syndromes.

We previously reported that the hypermethylation of the p15INK4B gene promoter was frequently observed in myelodysplastic syndromes (MDS), and that it may be associated with disease progression. An unanswered question is whether p15INK4B gene methylation is restricted to undifferentiated blastic cells, or whether differentiated cells such as granulocytes or erythrocytes of MDS origin also harbor this epigenetic alteration. In this study, we analyzed the methylation status of the p15INK4B gene in MDS by the methylation-specific PCR (MSP) method, which is more sensitive than Southern blotting. The bone marrow mononuclear cells (BM-MNCs) of 23 MDS patients were analyzed, and six of them showed p15INK4B methylation. Progenitor assay with methylcellulose medium was also performed in all patients. In two of the six patients with p15INK4B-methylated BM-MNCs, erythroid and/or non-erythroid colonies formed were subjected to molecular analysis. Colonies with and without p15INK4B methylation were detected in both patients. Furthermore, X-chromosome inactivation (XCI) pattern of each colony was simultaneously determined by MSP-based human androgen receptor gene analysis (HUMARA-MSP), and all p15INK4B-methylated colonies showed the same XCI pattern, which was dominant among the colonies, while p15INK4B-unmethylated colonies showed both patterns of XCI, in each of the two patients. We then examined the methylation status of the p15INK4B gene of granulocyte (PB-PMN) fractions from 10 patients with available peripheral blood cells. In all four patients with p15INK4B-methylated BM-MNCs, their PB-PMNs showed p15INK4B methylation. These results suggest that p15INK4B methylation in hematopoietic cells in MDS patients is restricted to the MDS clone but not necessarily to blast cells.

Acute Disease↗
PubMed1999

Case of intraductal papillary mucinous tumor (noninvasive adenocarcinoma) of the pancreas resected 27 years after onset.

A case of intraductal papillary mucinous tumor (IPMT) of the pancreas resected 27 yr after onset is presented. In March of 1997, a 71-yr-old man was admitted to our hospital with a complaint of severe epigastric pain. He had initially undergone endoscopic retrograde pancreatography (ERP) in April 1971 in our hospital and the patient had been followed up for pancreatografic changes for 26 yr. Dilatation of the main pancreatic duct gradually progressed during follow-up, and the filling defect owing to the tumor became demonstrable. On admission, ERP revealed diffuse dilatation of the main pancreatic duct, which was 20 mm in diameter, and the filling defect of 35 mm in diameter. We diagnosed this patient as having an IPMT of the pancreas. Considering his general condition, pancreatic segmentectomy was carried out, and the postoperative course was favorable. Histological findings were compatible with those of noninvasive papillary adenocarcinoma. This is a precious case for studying the natural history of intraductal papillary tumor of the pancreas and to evaluate the application of surgery, because the biologic behavior of this tumor is much less aggressive than that of pancreatic ductal cell carcinoma.

Adenocarcinoma↗