Mitsuharu Nakamoto

Study of 16,16-Dimethyl Prostaglandin E2 for Prevention of Stress Ulcer after Hepatectomy of Experimental Cirrhotic Liver and Its Influence on Hepatic Regeneration

The influence of 16,16-dimethyl prostaglandin E2 (16,16-dm PGE2; an agent used for the prevention of stress ulcer after hepatectomy of the cirrhotic liver) on liver regeneration after hepatectomy was studied in rats. The following results were obtained. Ulceration after the stress of 6 h of water immersion was markedly suppressed in rats treated with 30 r/kg of 16,16-dmPGE2 as compared with the untreated controls. In animals that received hepatectomy alone, the gastric pH and gastric mucosal blood flow showed significant reduction from the preoperative levels. In animals that received hepatectomy plus 16,16-dmPGE2 treatment the postoperative reduction in the gastric pH and gastric mucosal blood flow was suppressed, suggesting the effectiveness of 16,16-dmPGE2 treatment in the prevention of stress ulcer after hepatectomy of the cirrhotic liver. The 3H-thymidine uptake percentage and thymidine activity 24 h after hepatectomy and the DNA content 30 h after hepatectomy were significantly higher in animals treated with 16,16-dmPGE2 than in the untreated controls. In animals that were treated intraperitoneally with 50 mg/kg of indomethacin 6 h before hepatectomy the mitotic index 30 h after hepatectomy was markedly lower than that in untreated controls. This indomethacin-induced reduction in the mitotic index tended to be normalized by treatment with 16,16-dmPGE2. These results suggest that 16,16-dmPGE2 treatment effectively prevents stress ulcer and favorably affects hepatic regeneration after hepatectomy of the cirrhotic liver.

Release of γ-aminobutyric acid and acetylcholine by neurotensin in guinea-pig ileum

1 The release of γ‐aminobutyric acid (GABA) and acetylcholine (ACh) from the strips of guinea‐pig ileum was investigated in the presence of neurotensin. 2 Neurotensin evoked the release of [3H]‐GABA from the strips preloaded with [3H]‐GABA, and the evoked release was Ca2+‐dependent and tetrodotoxin‐sensitive. 3 Hexamethonium, scopolamine, [D‐Pro2, d‐Trp7,9] substance P and pretreatment with substance P did not alter the neurotensin‐evoked release of [3H]‐GABA. 4 Pretreatment with neurotensin inhibited the release of [3H]‐GABA evoked by neurotensin but not by high K+, thereby indicating that neurotensin induced a specific desensitization of its own receptor. These observations indicate that neurotensin may stimulate the GABAergic neurone through its own receptor. 5 Neurotensin evoked the release of [3H]‐ACh from strips preloaded with [3H]‐choline and this release was Ca2+‐dependent and tetrodotoxin‐sensitive. 6 The evoked release of [3H]‐ACh was not affected by hexamethonium, scopolamine and [D‐Pro2, d‐Trp7,9] substance P. 7 Bicuculline partly inhibited the neurotensin‐evoked release of [3H]‐ACh; thus neurotensin seems to induce a release of ACh partly through the release of endogenous GABA. 8 All this evidence indicates that neurotensin induces release of GABA as well as ACh from the myenteric neurones of the guinea‐pig ileum.

An Approach to the Mechanism of Acute Ulceration in Obstructive Jaundice

Changes of noradrenaline (NA) and prostaglandin (PG) E2 in gastric mucosa and gastric wall blood flow (GWBF) were investigated after stress load in rats with obstructive jaundice. We found that water immersion and restraint stress more easily increased the ulcer index and decreased GWBF, corresponding to a decrease of the NA and PGE2 contents in the gastric mucosa, as the duration of jaundice increased. Administration of PGE2 reduced the increase of the ulcer index and the decrease of the GWBF and NA contents in the gastric mucosa. It is suspected that the rapid decrease of NA and PGE2 is connected with the rapid decrease of GWBF after stress load in obstructive jaundice, and we reached the hypothesis that both PGE2 and NA mutually regulate local GWBF.

Incidence of esophageal injury after pulmonary vein isolation in patients with a low body mass index and esophageal temperature monitoring at a 39 °C setting

Esophageal injury following catheter ablation of atrial fibrillation (AF) is reported to occur in 35% of patients. Even with a low energy setting (20–25 W), lesions develop in 10% of patients. Body mass index (BMI) has been reported to be a predictor of esophageal injury, indicating that patients with a low BMI (<24.9 kg/m2) are at a higher risk. We hypothesized that catheter ablation with a lower energy setting of 20 W controlled by esophageal temperature monitoring (ETM) at 39 °C could prevent esophageal injury even in patients with a BMI <24.9 kg/m2.

Elderly case of Dieulafoy's lesion in the jejunum presenting with repeated hemorrhagic shocks

A 72-year-old man with hypertension was admitted to our hospital because of temporary stupor. On admission, neurological examination and brain magnetic resonance imaging showed no remarkable findings. Hemoglobin concentration of the blood was 14.4 g/dL. He developed shock following melena (day 1). Hematological examination after the shock revealed hemoglobin of 7.6 g/dL. Blood transfusion was performed. Initial gastrointestinal endoscopy and colonoscopy performed 4 h after the shock revealed blood in the colon, but did not reveal mucosal changes and the bleeding source. A second gastrointestinal endoscopy performed after a second shock revealed faint backward flow of the intestinal bleeding from the jejunum and did not show bleeding source in the esophagus, stomach and duodenum (day 2). Computed tomography (CT) and angiography performed on day 2 revealed the bleeding source (Fig. 1a– d). Although radiologists performed transcatheter arterial embolization (Fig. 1e), the patient developed a third shock following melena (day 4). A third gastrointestinal endoscopy showed a Dieulafoy’s lesion (DL) in the jejunum (Fig. 1f,g). We applied two clips and an endoscopic local injection of hypertonic saline– epinephrine solution. The hemostasis was successful. We could not perform gastrointestinal endoscopy after the treatment because of disappearance of melena and patient refusal. As in a similar previous report, we speculate that the DL in our case healed and disappeared. However, this could not be proven. Dieulafoy’s lesion is a vascular malformation and a rare but potentially life-threatening disease that is responsible for 7% of upper gastrointestinal hemorrhage. DL in the small intestine is extremely rare, and the diagnosis is difficult. In addition, elderly patients with DL can have several complications such as cardiovascular disease, chronic renal disease and dementia. Repeated hemorrhagic shocks can cause anemia and malnutrition, and worsen the general condition of elderly patients. Malnutrition among elderly patients leads to poor outcomes such as functional decline, frailty, the decline in quality of life and higher mortality. Nevertheless, DL located in the jejunum is beyond conventional gastrointestinal endoscopy. Angiography is useful for defining the lesion. Therefore, early detection of the bleeding source by repeated endoscopy, CT and angiography is necessary, and appropriate treatment is more important in elderly than young patients. Aging may be a risk factor for DL. The findings of DL in elderly patients suggest that atherosclerosis is associated with DL. DL also may be caused by an aneurysm in one of the vessels, perhaps in combination with atherosclerosis. Meanwhile, congenital or acquired vascular malformation might be an underlying cause in young patients. Although surgery had been performed in patients presenting with DL in the jejunum, endoscopic therapy is effective and safe in most cases. Endoscopic hemostasis is less invasive than surgery, especially for elderly patients. Although balloon-assisted enteroscopy recently has become practicable, this method was unavailable in our case. Transoral endoscopy accomplished by colonoscopy could be an alternative in emergency cases. This case highlights the unusual gastrointestinal hemorrhage that can induce repeated hemorrhagic shocks and malnutrition. The possibility of underlying causes in the small intestine should be kept in mind in patients with unusual gastrointestinal hemorrhage. Careful evaluation of the clinical and laboratory findings, and early treatment is important, especially in elderly patients. Geriatr Gerontol Int 2010; 10: 267–268

Elderly case of giant liver cyst presenting with inferior vena cava syndrome and decreased activities of daily life.

Decreased activities of daily life (ADL) in the elderly population is a major problem. Causes of decreased ADL in the elderly population are mainly cerebrovascular diseases, bone fracture by falls and dementia, but can also include geriatric syndrome, including frailty and a depressive status. Proper management of these causes might ameliorate decreased ADL. We herein present a rare case of an elderly patient complicated with inferior vena cava (IVC) syndrome as a result of a giant liver cyst (GLC) who developed decreased ADL because of severe leg edema. The patient was a 68-year-old woman who lived alone, and had a history of aortitis syndrome and cerebral infarction. She developed bilateral leg edema without abdominal pain. Two months later, her leg edema had worsened, and she developed fatigability, debility and a depressive status. Physical examination showed both paresis and atrophy of the muscles of the right arm and leg, and limited motion of the right shoulder, elbow and wrist joints as the sequelae of cerebral infarction. She gained 2 kg in 1 month. Marked pitting edema in the bilateral lower limbs and edema of the body wall were revealed. Laboratory examinations excluded hypoalbuminemia, hypothyroidism, heart failure and renal failure. Plain computed tomography (CT) showed GLC. Contrast-enhanced CT including reconstructed images showed that the cyst was compressing the IVC with dilatation of the IVC on the lower level with GLC (Fig. 1a–c). Neither a thrombus in the IVC nor a tumorous lesion in the cystic wall was present. Thus, we determined that her leg edema was caused by IVC compression as a result of GLC. The estimated volume of fluid within GLC on the reconstructed CT images was nearly 1.8 L. Six months after the onset of her leg edema, the cyst was percutaneously drained with aspiration of 2.4 L of fluid. She lost 6 kg in weight (from 57 to 51 kg) within 1 week after the drainage. She became free of bilateral leg edema, fatigability and depressive status. CT carried out 6 months after the drainage showed neither compression of the IVC nor dilatation of the IVC (Fig. 1d,e). Early diagnosis and treatment for such conditions is desirable, because the risks of thrombus formation within the IVC, rupture of the cyst and infection increase with age. These complications worsen the physical and mental condition, and decrease ADL in elderly patients. This patient’s physical activity and performance before the onset of leg edema was impaired because of the sequelae of cerebral infarction. These physical symptoms might have been the main trigger for her depressive status and decreased ADL; however, she recovered because of proper treatment of GLC. It is important to prevent reductions in physical activity in elderly individuals, because physical activity is associated with ADL and inversely correlates with the costs of medical care. In conclusion, we present a rare case of an elderly patient complicated with IVC syndrome as a result of GLC. It is important to pay attention to maintaining a good physical and mental condition in elderly patients.

Clinicopathological Study on Colorectal Cancer of Patients Over 80 Years of Age.

1985年1月より1989年12月までの5年間に当科で切除した大腸癌120例のうち, 高齢者の特徴を最も顕著に示すと思われる80歳以上の21例 (17.5%) を高齢者大腸癌として79歳以下の対照群99例と比較検討した.高齢者大腸癌は術前に治療を要する肺疾患や, 循環器系, 呼吸器系, 総蛋白量の異常を示す率が高率であった (p<0.05).占拠部位は高齢化に伴い右側結腸の占める割合が高くなる傾向にあった.壁深達度はss-alが61.9%と最も多く, 脈管侵襲ではV0が29.4%と低率 (p<0.05) で, n2以上のリンパ節転移率は23.5%と高齢者で高い傾向をみた.stage IV以上が42.1%と進行度の高い症例が対照群より多い傾向にあった.治癒切除率は対照群と遜色なかったが, 術後の合併症発生率は42.9%, 手術直接死亡率は4.8%と対照群に比し高い傾向があった.高齢者では術後に合併症を生じると重篤となりやすく, 緻密な術前・後の管理が必要である.

Studies on 7 cases of acute mesenteric arterial occlusive disease.

当科にて経験した急性腸間膜動脈閉塞症7例を対象とし, 臨床的特徴, 予後に影響する因子などについて検討した.平均年齢は68.3歳, 全例に循環器系疾患などの併存を認めた.アシドーシスを5例 (71.2%), 白血球増多を4例 (57.1%) に認めた.全例に小腸広範囲切除を施行し, 4例 (57.1%) が直死した.直死例の平均年齢は75.8歳と高く, また発症より手術までの平均時間は78時間で, 生存例の16時間に比べて長い傾向を示した.白血球増多例の75.0%が直死したのに対して, 白血球正常例の直死は33.3%のみであった.直死4例のうち3例は, 術後再度の血行障害によると思われる縫合不全や消化管穿孔を契機として死亡した.本症の予後を向上させるためには, 術後の腸管壊死を避けるために種極的な腸切除が必要であるが, それ以前に血管造影などを駆使した早期診断が重要と思われた.

CLINICOPATHOLOGICAL AND IMMUNOHISTOLOGICAL STUDIES AND PROGNOSIS OF PRIMARY MALIGNANT LYMPHOMA OF THE SMALL INTESTINE

切除した小腸原発性悪性リンパ腫5例を対象に, 臨床病理学, 免疫組織学的検討を行った. 性別は4: 1, 手術時平均年齢は62.2歳, 病悩期間は平均3.3か月であった. 臨床症状は腹痛を全例に認めたが, 悪性リンパ腫に特異的な症状はなかった. 発生部位は空腸1例, 回腸4例, 肉眼型は潰瘍型3例, 動脈瘤型2例で, 腫瘍径は全例4cm以上 (平均8.0cm) と大きく, 多発症例は2例あった. 免疫組織学的検索では全例B細胞由来リンパ腫で, このうち, 2例に腫瘍細胞質内に免疫グロブリン局在を認め, 1例はIgGλ 型, 1例はIgMλ 型であった. 腫瘍径と予後の関連性は見出せなかったが, 深達度, リンパ節転移, 進行度との関連性は示唆できた.

CLINICAL STUDIES ON PANCREATITIS ACCOMPANIED WITH PEPTIC ULCERS

慢性膵炎手術46例を対象として, 膵内外分泌能と酸分泌能を対比し, さらに潰瘍成因について防御因子の面より粘膜ウロン酸を測定した. 潰瘍合併率は30.6%と高率であったが, MAOは正酸から低酸を示すのがほとんどで, 潰瘍合併例のMAOは非合併例よりも低値を示す症例が多かった. P-S試験, OGTT insulinogenic indexを指標として, 膵内外分泌障害の程度とMAO, ガストリンを比較したが相関はなかった. 胃粘膜ウロン酸量は胃潰瘍例と似た値を示し, 防御能の低下が示唆された. 潰瘍合併例に対する術式は潰瘍を含む胃切除を基本とし, 迷切術の併用は胃防御能を低下することから好ましくないと思われた.