Evolution to acute myeloblastic leukemia from chronic neutrophilic leukemia with dysplastic features in granulocytic lineage

We experienced the case of an 82-year-old man with chronic neutrophilic leukemia (CNL) with dysplastic features in the granulocytic lineage which subsequently progressed to acute myeloblastic leukemia (AML) with myelofibrosis. The patient had hepatosplenomegaly, but there was no evident cause of neutrophilic leukocytosis. The cytogenetic study showed that he had a normal karyotype. Concentrations of the serum granulocyte colony-stimulating factor (G-CSF) were not detectable. Two years after the diagnosis of CNL, blastic transformation to AML occurred with myelofibrosis and significant morphological abnormalities in neutrophils. The blasts were positive for myeloperoxidase, CD33, CD34, and HLA-DR, and the presence of dysplasia within the granulocytic lineage suggested that he had an abnormality at the level of the granulocyte-committed progenitors. Heterogeneous origins of CNL might lead to various clinicopathological features in each case.     

Combination of flecainide and propranolol for congenital junctional ectopic tachycardia

Congenital junctional ectopic tachycardia is a rare tachyarrhythmia with high mortality. A pharmacological approach in early infancy is regarded as the first‐line therapeutic option. Pharmacologically, amiodarone alone or in combination with other drugs is the most commonly reported effective agent for congenital junctional ectopic tachycardia, but it has many adverse effects. Here we report the case of a 40‐day‐old infant. The clinical course suggests that combined oral flecainide and propranolol is an effective alternative therapy for early infants. Esophageal lead electrocardiography may give a clear diagnosis of junctional ectopic tachycardia.     

Successful laparoscopic extirpation of a large omental lipoblastoma in a child

Omental lipoblastoma is extremely rare among benign tumors. We herein report the case of a child who underwent laparoscopic extirpation of a large omental lipoblastoma. A 4‐year‐old girl was diagnosed with an intra‐abdominal solid tumor. Abdominal imaging revealed a fat density mass that was well encapsulated and measured 18 × 15 × 7.5 cm in size. Considering the MRI findings and movability of the tumor, we strongly suspected that the lesion was an omental lipoblastoma. We initially decided to perform laparoscopic exploration and, if possible, extirpation of the solid tumor sequentially. A total of five trocars were used, and the tumor was found to originate from the omentum. We successfully performed complete resection of the tumor laparoscopically. A histological examination revealed lipoblastoma. For large abdominal tumors in children, the laparoscopic approach is recommended as the first procedure when the tumor is preoperatively considered to be benign and resectable.     

Strictureplasty for short duodenal stenosis in Crohn's disease

Involvement of the gastroduodenum is extremely rare in Crohn's disease. For obstructing duodenal Crohn's disease, bypass procedures have traditionally been selected. However, more recently, strictureplasty has become an acceptable surgical option. We treated two Crohn's disease patients with short proximal duodenal stenosis, using Finney-type strictureplasty. Their postoperative courses were uneventful and they have remained asymptomatic during follow-up periods of more than 5 years, and 4 months, respectively. Owing to the good clinical results of our two patients, we consider strictureplasty to be indicated for short proximal duodenal stenosis in Crohn's disease. Received: October 14, 1999 / Accepted: February 25, 2000     

Antifibrotic effect of adrenomedullin on coronary adventitia in angiotensin II-induced hypertensive rats

OBJECTIVE: The extracellular matrix (ECM) determines the structural integrity of the heart and vasculature, participating in cardiovascular remodeling. We previously reported that adrenomedullin (AM) inhibited cellular proliferation and protein synthesis of cardiac fibroblasts; however, the precise mechanisms of AM actions as an antifibrotic factor remain unknown. The purpose of this study was to examine the biological actions of AM against the profibrotic factor angiotensin II (Ang II) in coronary adventitia. METHODS AND RESULTS: Rats with hypertension induced by Ang II infusion were administered 0.06 mug/kg/min recombinant human AM subcutaneously for 14 days. The AM infusion significantly (p<0.05) reduced the Ang II-induced increase of coronary adventitial fibroblasts expressing Ki-67 and alpha-smooth muscle actin (alpha-SMA) in the left ventricle, by 65%, and 62%, respectively, without affecting systolic blood pressure, left ventricle/body weight, or cross-sectional area of myocardial fibers. Collagen deposition of coronary arteries was reduced by the AM infusion (-24%, p<0.01), and these effects of AM were accompanied by significant reductions in gene expression of type 1 collagen (-49%, p<0.05) and transforming growth factor-beta1 (TGF-beta1) (-55%, p<0.01). In cultured cardiac fibroblasts, 10(-7) mol/L AM exerted an inhibitory effect on TGF-beta1-induced alpha-SMA expression (p<0.01) that was mimicked by 8-bromo-cAMP and attenuated by the protein kinase A inhibitor H-89. CONCLUSION: AM decreased Ang II-induced collagen deposition surrounding the coronary arteries, inhibiting myofibroblast differentiation and expressions of ECM-related genes in rats. The present findings further support the biological action of AM as an antifibrotic factor in vascular remodeling.     

Gastrin Release from Antral G Cells Stimulated with Secretin

Recently, gastrinoma cells were demonstrated to release gastrin when directly stimulated by secretin both in vivo and in vitro. In this study, the reaction of antral G cells was investigated. Secretin was injected into the right gastroepiploic artery in canines, and into the common hepatic artery during a selective arteriography in patients without gastrinomas. G cells obtained from the antrum of rats were attached to 0.45-microns filters and irrigated with medium containing secretin. The serum gastrin concentration increased rapidly in significant amounts and very quickly after an intraarterial injection of secretin, both in humans and in dogs. The rate of gastrin release from the rat antral G cells in vitro increased significantly when the medium contained secretin. In conclusion, secretin stimulated gastrin release from antral G cells both in vivo and in vitro.     

A seasonal variation in the onset of postoperative adhesive small bowel obstruction is related to changes in the climate

BACKGROUND: Postoperative small bowel obstruction following abdominal procedures is more common in patients who have undergone laparotomy. However, little is known about the influence of climate on the incidence of postoperative small bowel obstruction. METHODS: To evaluate whether seasonal climatic variations are a risk factor for postoperative small bowel obstruction, hospital-based, retrospective case series was designed from medical records of 230 patients suffering from postoperative small bowel obstruction admitted to the Tokyo University Branch Hospital. Detailed analysis of weather charts from the Japanese Meteorological Agency and review of medical records for selected patients who were diagnosed with postoperative small bowel obstruction. The obstruction was diagnosed by abdominal X-ray imaging, clinical examination, and patient interviews. RESULTS: A total of 233 patients diagnosed with postoperative small bowel obstruction were identified. Analysis of the medical records of these 233 patients revealed that the variables associated with an increased risk of postoperative small bowel obstruction included low ambient temperatures of 5-10 degrees C, an increase in air humidity by 40-50% and air pressure of 1010-1015 hPa. CONCLUSION: The typical winter weather in Tokyo is characterised by low temperatures, low humidity and moderate air pressure. These winter climate conditions could be correlated with an increased incidence of postoperative small bowel obstruction in Tokyo during our period.     

Crystal structure of a central stalk subunit C and reversible association/dissociation of vacuole-type ATPase

The vacuole-type ATPases (V-ATPases) exist in various intracellular compartments of eukaryotic cells to regulate physiological processes by controlling the acidic environment. The crystal structure of the subunit C of Thermus thermophilus V-ATPase, homologous to eukaryotic subunit d of V-ATPases, has been determined at 1.95-A resolution and located into the holoenzyme complex structure obtained by single particle analysis as suggested by the results of subunit cross-linking experiments. The result shows that V-ATPase is substantially longer than the related F-type ATPase, due to the insertion of subunit C between the V(1) (soluble) and the V(o) (membrane bound) domains. Subunit C, attached to the V(o) domain, seems to have a socket like function in attaching the central-stalk subunits of the V(1) domain. This architecture seems essential for the reversible association/dissociation of the V(1) and the V(o) domains, unique for V-ATPase activity regulation.     

Coexpression of CD40 and CD40 ligand in Epstein-Barr virus-infected T and NK cells and their role in cell survival

We investigated the role that CD40-CD40 ligand (CD40L) signaling plays in survival of Epstein-Barr virus (EBV)-infected T and NK cells. EBV-infected T and NK cell lines derived from patients with either chronic active EBV infection (CAEBV) or nasal T/NK cell lymphoma, as well as virus-infected peripheral T cells freshly isolated from a patient with CAEBV, were shown to express both CD40 and CD40L on their surface. Apoptosis of these cells was enhanced by blockade of CD40-CD40L signaling by a fusion protein of CD40 and immunoglobulin G (CD40Ig). Expression of CD40 was induced in human CD40L-positive Jurkat T cells after experimental EBV infection, and apoptosis of infected cells was enhanced by CD40Ig. These results suggest that CD40-CD40L signaling promotes survival of EBV-infected T and NK cells and, thus, plays an important role in the pathogenesis of T/NK lymphoproliferative disorders associated with the virus.