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Dive into the research topics where Yasuo Hayashida is active.

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Featured researches published by Yasuo Hayashida.


Virus Genes | 2006

Analysis of human immunodeficiency virus type 1 integration by using a specific, sensitive and quantitative assay based on real-time polymerase chain reaction.

Norio Yamamoto; Chika Tanaka; YuFeng Wu; Myint Oo Chang; Yoshio Inagaki; Yasunori Saito; Toshio Naito; Hitoshi Ogasawara; Iwao Sekigawa; Yasuo Hayashida

A novel real-time nested-PCR assay was developed to quantify integrated human immunodeficiency virus type-1 (HIV-1) DNA with high specificity and sensitivity. This assay reproducibly allowed the detection of three copies of integrated HIV DNA in a background of 100,000 cell equivalents of human chromosomal DNA. The non-specific amplification of unintegrated HIV-1 DNA was significantly inhibited in this assay and the specificity of this assay was much higher than the previously reported method. This assay showed that kinetics in viral DNA sysnthesis was cell-type dependent and that the kinetics of HIV-1 DNA integration was very rapid in Jurkat T cell line. This method may provide new insights into the integration processes and be useful in evaluating future integrase inhibitors.


Clinical Rheumatology | 2007

Estrogen receptor expression by peripheral blood mononuclear cells of patients with systemic lupus erythematosus

Akihiro Inui; Hitoshi Ogasawara; Toshio Naito; Iwao Sekigawa; Yoshinari Takasaki; Yasuo Hayashida; Kenji Takamori; Hideoki Ogawa

To investigate the influence of sex hormones on the development of systemic lupus erythematosus (SLE), we examined the estrogen receptor (ER) expression by peripheral blood mononuclear cells (PBMC) in patients with SLE using the real-time quantitative polymerase chain reaction (TaqMan) method. The expression of messenger RNA (mRNA) for ER alpha (ERa) was increased and expression of ER beta (ERb) mRNA was decreased in PBMC from SLE patients compared with PBMC from normal controls. These findings may be useful for elucidation of the pathophysiology of SLE.


Renal Failure | 2007

Eradication of Helicobacter pylori in Hemodialysis Patients

Tomoko Itatsu; Hiroto Miwa; Akihito Nagahara; Minoru Kubota; Akihisa Miyazaki; Nobuhiro Sato; Yasuo Hayashida

Background. Helicobacter pylori (H. pylori) are a causative agent of digestive disease. Although a proton pump inhibitor combined with amoxicillin-clarithromycin is the accepted drug treatment for H. pylori eradication in Japan, there is no consensus treatment for hemodialysis patients. Study. Seventy-seven hemodialysis patients underwent upper digestive tract endoscopy. Biopsy specimens were taken, and histological findings, culture, and rapid urease tests were performed to confirm the presence of H. pylori. H. pylori-positive patients were then administered at random either a seven-day lansoprazole (60 mg a day)-amoxicillin (750 mg a day)-clarithromycin (400 mg a day) (LAC) regimen or a seven-day lansoprazole (60 mg a day)-clarithromycin (400 mg a day) (LC) regimen. The success of H. pylori eradication was determined from histological findings, culture, and rapid urease tests. Results. In 13 of 77 patients (13.6%), ulcers and/or ulcer scars were seen by endoscopy. Thirty-one patients (40.3%) were positive for H. pylori, and 20 patients among them were randomized to one of two regimens: one is seven-day LAC regimen (eleven patients) and the other is seven-day LC regimen (nine patients). Eradication was successful in nine of the eleven patients (72.7%) receiving the LAC regimen, but in only three of the nine patients (33.3%) who underwent the LC regimen. No serious adverse effects were observed with either regimen, and 95% of the patients reported complete compliance. Conclusion. A seven-day low dose LAC regimen is safe and effective and recommended for treatment of H. pylori infection in hemodialysis patients.


Journal of Gastroenterology | 2000

Metastatic gastrinoma to the liver 20 years after primary resection

Atsushi Okuzawa; Shigeru Kobayashi; Kazuhiro Sakamoto; Yousuke Uchida; Yoshimasa Suzuki; Ken Ono; Eiichirou Seki; Y. Tomiki; Yoshimi Iwanuma; Yasuo Hayashida; Toshiki Kamano; Masahiko Tsurumaru

Abstract: Gastrinoma is a rare endocrine tumor that is frequently associated with liver metastasis. The liver metastasis is usually seen simultaneously or soon after a primary operation. A 47-year-old woman who had had a total gastrectomy 20 years earlier developed liver metastasis. An interval of this length between surgery and metastasis is extremely rare. The total gastrectomy prevented the patient from developing the usual symptoms of hypergastrinemia that would have enabled early diagnosis of the metastasis. Laboratory examinations on admission revealed a high serum gastrin concentration (1500 pg/ml). Computed tomography showed an irregularly enhanced mass lesion with an uneven, low-density central area in the right anterior inferior segment of the liver. An extended right hepatectomy was performed. Intraoperative ultrasonography showed no abnormalities in the remnant pancreas. Examination of the cut surface of the specimen revealed a yellow, firm, elastic tumor, 55 mm in diameter. The interior of the tumor appeared necrotic. Histopathologically, the tumor was composed of cells with hyperchromatic, dysplastic nuclei arranged in a trabecular pattern with nest formation. Gastrin staining was positive. A histologic diagnosis of metastatic gastrinoma was made. The patients gastrin concentration returned to normal and she was well at 2-year follow-up.


Asian Journal of Surgery | 2004

Mucosal Neuroendocrine Cell Abnormalities in Patients with Chronic Constipation

Akiko Kobayashi; Yasuo Hayashida; Hiroo Yokota; Hiroyuki Kobayashi; Atsuyuki Yamataka; Takeshi Miyano

OBJECTIVES The aim of this study was to examine the distribution of neuroendocrine cells (NEC) in patients with chronic constipation (CC) as a means of establishing a relationship between pathology, symptomatology and treatment. METHODS Rectal biopsy specimens from 43 patients with CC (aged 17-82 years) and 20 age-matched normal controls were examined histopathologically using haematoxylin and eosin, and immunohistochemically using antibodies against chromogranin-A (Ch-A) and serotonin (5-HT) to detect NEC. The number of positive NEC per 70 crypts (CR) was counted and expressed as the ratio of NEC/CR. CC patients were divided into groups based on management, then compared using NEC/CR. RESULTS CC was managed conservatively in 29 patients (group A) and invasively in 14. Of these 14, 10 had normal histology (group B) and four had typical histopathological signs of intestinal neuronal dysplasia (IND; group C). All control specimens were unremarkable. In controls, NEC/CR was 0.94+/-0.33 for Ch-A and 0.32+/-0.08 for 5-HT. In group A, NEC/CR was 2.23+/-0.13 for Ch-A and 1.02+/-0.06 for 5-HT. In group B, it was 2.79+/-0.18 for Ch-A and 1.72+/-0.33 for 5-HT. In group C, it was 3.12+/-0.22 for Ch-A and 2.32+/-0.14 for 5-HT. The increase in Ch-A and 5-HT immunoreactive cells in groups B and C compared with controls was greater (p<0.01, p<0.05) than the increase seen in group A compared with controls (p<0.01, p<0.05). CONCLUSIONS These results demonstrate that increased numbers of NEC may play a role in the abnormal bowel function seen in CC, and may have some relationship with the development of giant submucosal ganglia in IND.


Digestive Endoscopy | 2000

Cancer Cell Exfoliation by Preoperative Colonoscopic Examination

Yuichi Tomiki; Toshiki Kamano; Yasuo Hayashida; Tsuyoshi Okada; Yasuhiro Kunii; Yoshiro Ishibiki; Yoshihiko Kawase; Masahiko Tsurumaru

Background: Colonoscopic contact and repeated biopsies have been associated with an increased risk of cancer cell dissemination. We examined whether exfoliated cancer cells were detected during preoperative colonoscopic examination in patients with colorectal cancer.


Digestive Endoscopy | 2006

RELATION BETWEEN RESPIRATORY SUPPRESSION FROM SEDATION DURING ENDOSCOPY AND VITAL CAPACITY

Yuichi Tomiki; Koji Shinmura; Shinji Kasamaki; Kiyoshi Terai; Tsutomu Maeda; Ryohei Takeda; Makoto Takahashi; Yukihiro Yaginuma; Kazuhiro Sakamoto; Takashi Nakajima; Toshiki Kamano; Yasuo Hayashida

Background:  Respiratory suppression is observed during endoscopy under sedation. If respiratory suppression can be predicted before endoscopy, incidental complications can conceivably be prevented. In the present study, we focused on the relation between respiratory suppression from sedation and lung function.


Digestive Endoscopy | 2002

Acute Gastric Mucosal Injury Caused by Ingestion of Chlorinated Fungicide

Shinji Kasamaki; Shigeru Kobayashi; Yasuo Hayashida; Shu Hirai; Takumi Ochiai; Hironobu Motoyama; Hiroo Yokota

We encountered a patient with acute gastric mucosal injury caused by ingestion of a chlorinated fungicide. Approximately 15 h after the episode of ingestion, endoscopic views were compatible with the acute gastric mucosal lesion of severe degree throughout the stomach. At that time, endoscopic biopsy showed congestion in the epithelial layer of the mucosa, along with lymphocytic infiltration that had likely existed from the onset of the condition. On the third day, the mucosal lesion looked more serious with peculiar hemorrhagic folds, and biopsy revealed exfoliation of the epithelial surface and neutrophilic infiltration in the stroma of the epithelial layer. On the seventh day, endoscopic images showed persistence of the lesion, but biopsy demonstrated the development of regenerating epithelium along with a marked reduction in infiltration of neutrophils and edema in the stroma.


Digestive Endoscopy | 1999

A Case of Esophageal Cyst Excised Successfully Using Laparoscopy

Kazuhiro Sakamoto; Noboru Mizobuchi; Kenji Narumi; Suguru Watabe; Atsushi Okuzawa; Shigeru Shirota; Yoshiaki Kajiyama; Shigeru Kobayashi; Yasuo Hayashida; Toshiki Kamano; Masahiko Tsurumaru; Hitoshi Funabiki

Laparoscopic excision of an esophageal cyst was successfully performed on a 29‐year‐old male. The patient, complaining of back pain, was admitted to our hospital for further evaluation of a submucosal esophageal tumor. Close examination revealed a cystic tumor originating from the proper muscular layer at the distal esophagus, measuring 3 cm in diameter. Under general anesthesia, the tumor was excised laparoscopi‐cally without esophageal mucosal injury, with monitering by esophagoscopy. Postoperative esophagography showed no stagnation or stenosis. He was discharged on the 11th postoperative day. The cyst was diagnosed pathologically as an inclusion cyst of the esophagus. Laparoscopic or thoracoscopic surgery is a useful treatment for benign esophageal tumors, because it is less invasive giving more rapid recovery. Concomitant esophagoscopic monitering is beneficial to avoid injury of the esophageal mucosa, especially in such benign tumors that are firmly adherent to the esophageal muscle and mucosal layer.


Digestive Endoscopy | 1997

A Clinical Study of Acute Pancreatitis following Endoscopic Retrograde Cholangiopancreatography

Ken Ono; Shigeru Kobayashi; Kazuhiro Sakamoto; Yasuo Hayashida; Noburu Sakakibara

Abstract: Endoscopic retrograde cholangiopancreatography (ERCP) has been established as a safe and effective examination for patients with pancreatobiliary diseases. Pancreatitis following ERCP is an extremely rare complication. However, once pancreatitis occurs, patients may deteriorate developing a severe condition. This study was designed to investigate the cause of this pancreatitis with the aim of minimizing complications.

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