Identification of cardiac-specific myosin light chain kinase

Two myosin light chain (MLC) kinase (MLCK) proteins, smooth muscle (encoded by mylk1 gene) and skeletal (encoded by mylk2 gene) MLCK, have been shown to be expressed in mammals. Even though phosphorylation of its putative substrate, MLC2, is recognized as a key regulator of cardiac contraction, a MLCK that is preferentially expressed in cardiac muscle has not yet been identified. In this study, we characterized a new kinase encoded by a gene homologous to mylk1 and -2, named cardiac MLCK, which is specifically expressed in the heart in both atrium and ventricle. In fact, expression of cardiac MLCK is highly regulated by the cardiac homeobox protein Nkx2-5 in neonatal cardiomyocytes. The overall structure of cardiac MLCK protein is conserved with skeletal and smooth muscle MLCK; however, the amino terminus is quite unique, without significant homology to other known proteins, and its catalytic activity does not appear to be regulated by Ca(2+)/calmodulin in vitro. Cardiac MLCK is phosphorylated and the level of phosphorylation is increased by phenylephrine stimulation accompanied by increased level of MLC2v phosphorylation. Both overexpression and knockdown of cardiac MLCK in cultured cardiomyocytes revealed that cardiac MLCK is likely a new regulator of MLC2 phosphorylation, sarcomere organization, and cardiomyocyte contraction.     

Extensive left atrial endoatriectomy for infective endocarditis

The technique of extensive endoatriectomy of the left atrium and reconstruction with autologous pericardium for infective endocarditis is described. Endocardium of the left atrium with vegetations was completely excised from the valvular annulus to normal endocardium, and autologous pericardium was used to reinforce the endocardial defect and to allow less tension in the closure. This technique permits complete removal of infectious lesions and facilitates mitral valve replacement reinforcing the mitral annulus.     

Early removal of bile duct stones in patients with acute biliary pancreatitis by endoscopic papillary balloon dilatation

BACKGROUND/AIMS: Endoscopic papillary balloon dilatation has been accepted as a novel alternative to endoscopic sphincterotomy for the management of bile duct stones. Hence, little or no attempt was made to retrieve stones in cases with acute biliary pancreatitis by endoscopic papillary balloon dilatation. METHODOLOGY: The present study was conducted in ten patients with acute biliary pancreatitis associated with cholestasis or biliary infection. Two patients came with disseminated intravascular coagulopathy, one Child C liver cirrhosis, and another with prolonged prothrombin time of unknown etiology. After the papilla was dilated with a balloon-tipped catheter, the stones were removed with either a retrieval basket catheter, a retrieval balloon, or both. RESULTS: Clearance of the common bile duct was achieved in all ten patients without any serious complications such as pancreatitis aggravation or hemorrhage. Clinical signs and laboratory findings were strikingly improved in all patients. CONCLUSIONS: The results suggest that bile duct stones can be effectively and safely removed by means of endoscopic papillary balloon dilatation even in patients with acute pancreatitis.     

A case of leptospirosis caused by Leptospira borgpetersenii serovar sejroe infected in Bali Island, Indonesia

We report a patient with leptospirosis caused by Leptospira borgpetersenii serovar Sejroe infection on Bali Island, Indonesia. This 33-year-old Japanese man had stayed at a resort hotel on the island from July 8 to July 13 2004. At the hotel, he swam in the pool, walked barefoot, and lied down in the grass. He developed a high fever and headache 7 days after completing his trip, and was admitted to our hospital on July 23. On admission he showed conjunctival suffusion and complained of myalgias. Laboratory findings included granulocytosis and elevated CRP. Plasmodium spp. were not found in blood smears, and no pathogenic bacteria were isolated from blood or fecal cultures. We diagnosed the patient as leptospirosis upon detection of slender coiled organisms with characteristic morphology by darkfield examination of blood sample. Minocycline 100 mg i.v.b.i.d. showed excellent efficacy. A microscopic agglutination test (MAT) during the convalescent stage demonstrated a significant increase in antibodies against L. borgpetersenii serovar Sejroe, confirming the diagnosis of leptospirosis. Despite occurrence of a pandemic of leptospirosis in certain Southeast Asian countries including Indonesia, information concerning pandemic disease is limited. In addition serovars of "imported" cases representing infection in pandemic areas differ widely from those in domestic cases. Adequate laboratory support therefore is crucial for accurate diagnosis of leptospirosis.     

Simultaneous DNA Typing of Human Platelet Antigens 2, 3 and 4 by an Allele-Specific PCR Method

We developed an allele-specific polymerase chain reaction (ASPCR) method using originally designed primers to determine the genotype of the human platelet antigens (HPAs) 2, 3 and 4 in parallel. The results were compared with those obtained by PCR restriction fragment length polymorphism and the mixed passive hemagglutination test. Seventy-three individuals were tested and the ASPCR results were in good agreement with those determined by the other two methods. This method enables the genotyping of HPA-2, -3 and -4 in parallel without the use of platelets, platelet-specific alloantibodies or restriction enzymes.     

Increased soluble platelet/endothelial cell adhesion molecule-1 in the early stages of acute coronary syndromes

Specific molecules including inflammatory cell adhesion molecules mediate attachment of blood leukocyte and platelets to the endothelium and mononuclear cell migration into the arterial intima. However, the clinical significance of soluble cell adhesion molecules very early in the course of acute coronary syndrome is not known. We assayed platelet/endothelial cell adhesion molecule-1 (PECAM-1, CD31), intercellular adhesion molecule-1 (ICAM-1, CD54), and P-selectin (CD62P) in plasma obtained from 20 patients within 3 h after the onset of acute myocardial infarction (AMI); 16 patients with unstable angina pectoris; 20 patients with stable angina pectoris, and 28 controls. Blood samples were obtained on hospital admission and again 1 week after onset of AMI and unstable angina, and on admission in patients with stable angina and controls. Plasma PECAM-1 concentration (ng/ml) on admission was higher in patients with AMI (25.6±4.7) and unstable angina (24.7±4.4) than in stable angina (20.5±4.4) and control (18.8±3.8) groups. In both AMI and unstable angina, plasma PECAM-1 had decreased significantly by 1 week (AMI, 20.8±4.0; unstable angina, 21.0±4.1). Plasma ICAM-1 concentration (ng/ml) on admission was higher in patients with AMI (254±70), unstable angina (264±78), and stable angina (245±68) than in controls (201±56), but did not differ between the three coronary syndromes. Plasma P-selectin concentration did not differ between the four groups, including controls. Therefore, soluble PECAM-1 concentration may be a sensitive markers providing early diagnostic aid in acute coronary syndromes.     

Biliary cystadenocarcinoma followed up as benign cystadenoma for 10 years

We describe a case of biliary cystadenocarcinoma that showed a longterm clinical course. A 69-year-old Japanese man was admitted to our hospital because of abdominal discomfort. The patient had been diagnosed with benign cystadenoma of the liver at another hospital in 1987 and had been followed up for 10 years. Abdominal ultrasonography (US) and computed tomography (CT) scan demonstrated a unilocular cystic lesion, which included multiple conspicuous papillary protrusions in the left hepatic lobe. Left lateral segmentectomy was performed, and intraoperative cholangiography revealed a communication between the cystic tumor and intrahepatic bile duct. The tumor contained clear mucinous fluid and enfolded multiple yellowish papillary projections on the cystic wall. Histological examination showed the tumor to be biliary cystadenocarcinoma. The patient is doing well 4 years after the operation.     

Evaluation of the densitometric method of ejection fraction by direct digital subtraction left ventriculography

The aim of the present study was to test the hypothesis that the densitometric ejection fraction (EF) could be calculated by direct contrast digital subtraction left ventriculography in a single heartbeat. Thirty patients underwent direct contrast digital subtraction left ventriculography and biplane conventional left ventriculography. The values of EF were obtained from digital subtraction ventriculograms of the first cardiac cycle after completion of the injection of the contrast medium by the videodensitometric technique and were compared with those obtained from conventional ventriculograms by the arealength method in the same patients. There was a close correlation between the densitometric EF from digital subtraction ventriculograms and the volumetric EF from conventional ventriculograms (r = 0.78). Densitometric EF measured in the 30° right anterior oblique projection highly correlated with densitometric EF measured in the 60° left anterior projection (r = 0.98). These data suggest that this densitometric technique is available in any projection and is a simple procedure for the accurate measurement of left ventricular EF.     

A case of atypical pulmonary carcinoid accompanying skin metastasis]

A 73-year-old woman underwent cranial surgery in 1999 after receiving a diagnosis of suspected malignant meningioma. She began complaining of headache 2 years postoperatively, and around the same time, she noticed a painful skin tumor. She was then transferred to our hospital for further evaluation. The skin tumor was diagnosed by skin biopsy as an atypical metastatic carcinoid tumor. Systemic examination demonstrated a primary lesion in the left lung. Pulmonary, skin and bone biopsy samples exhibited the same pathological findings as those of the atypical pulmonary carcinoid tumor. She did not show any carcinoid symptoms. EP therapy (etoposide + carboplatin) and CAV therapy (cyclophosphamide + doxorubicin + vincristin) were administered, but there was no clinical response. The patient is currently doing well without chemotherapy and is being followed by the Outpatient Department.     

Analysis of Promoter Region of X-Linked pgk-1 Gene Polymorphisms: Evidence for Polyclonality of Adult Mouse Gastric Glands

The clonality of gastric glands remains a controversial topic. Chimeric mouse studies suggested that all gastric glands were monoclonal. However, using the X-linked transgenic mouse model, we have suggested that most glands are polyclonal during development and that the fraction of monoclonal glands increases after birth. Nevertheless, a fraction of glands is perpetually polyclonal even in the adult murine stomach. To examine the existence of gastric polyclonal glands in the adult mouse, we studied an X-linked intrinsic polymorphic gene, pgk-1, in 6 week-old female mice heterozygous for the X-linked pgk-1a and pgk-1b. The sequence containing the seventh HpaII site in the promoter region of the gene and the polymorphic sites was utilized. Twenty-four of 225 fundic glands (10.7%) and 3 of 167 pyloric glands (1.8%) were clonally heterotypic. Only 0.6% of colonic crypts were heterotypic. Clonally heterotypic glands with inactive X-specific methylation were present in the adult murine stomach.