Ectopic expression of c-myc fails to overcome downregulation of telomerase activity induced by herbimycin A, but ectopic hTERT expression overcomes it

Telomerase plays a key role in the maintenance of chromosomal stability in tumors, but the mechanism regulating telomerase activity is still unclear. Recent studies have suggested that c-myc may be vital for regulation of hTERT mRNA expression and telomerase activity. In this study, we investigated the changes of telomerase activity and telomerase-related genes induced by herbimycin A in K562 human chronic myelogeous leukemic cells. Telomerase activity showed a biphasic pattern in herbimycin A-treated K562 cells. Initially, the telomerase activity decreased along with the decline of cells in S and G2/M phases, but it recovered slightly at the end of treatment. Expression of mRNA for the telomerase catalytic subunit (hTERT) was decreased before the decline of telomerase activity, and increased slightly before the reactivation of telomerase activity. During herbimycin A treatment, both c-myc and cyclin D1 mRNA showed transient downregulation before the increase of G1 cells. Herbimycin A treatment caused the downregulation of both telomerase activity and hTERT mRNA in cyclin D1-transfected K562 cells, while telomerase activity was partially restored in c-Myc-transfected cells. In contrast, hTERT-transfected K562 cells maintained a high level of telomerase activity during herbimycin A treatment. Neither the template RNA component of telomerase (hTERC) nor telomerase-associated protein (TEP-1) were altered in any of the transfected K562 cells. These results indicate that telomerase activity is mainly regulated by hTERT, and that c-Myc protein is one of the positive regulators of hTERT in leukemic cells but is not enough to counteract the downregulation of telomerase activity by herbimycin A completely.

Treatment of solitary small hepatocellular carcinoma: consideration of hepatic functional reserve and mode of recurrence

BACKGROUND/AIMS

Hepatocellular carcinoma (HCC) recurs frequently after initial treatment. The subsequent prognosis varies with the mode of recurrence. Some patients die of hepatic failure even though the HCC is controlled. We consider the clinical stage (CS), using the modified Child-Pugh classification, to be an important factor influencing the prognosis of these patients.

METHODOLOGY

To determine the most effective treatment for HCC, we examined 105 patients with solitary small HCC who were followed-up for more than 1 year after initial treatment. All of them were judged to be cured according to imaging or histological studies. The initial treatments were hepatic resection (n = 43), percutaneous ethanol injection therapy (PEIT, n = 33), and percutaneous microwave coagulation therapy (PMCT, n = 29). The modes of recurrence were divided into intrahepatic metastasis (IM) and multicentric occurrence (MO).

RESULTS

Prognosis of MO was superior to that of IM in CS I patients, but there was no difference in prognosis between these modes in CS II. The hepatic resection group had more MO recurrences in CS I patients and more IM recurrences in CS II patients. IM developed frequently after PEIT and PMCT, regardless of the CS. Prognosis with hepatic resection was superior to that of the other treatments in CS I patients, but there was no difference in prognosis among the 3 treatment modalities in CS II patients.

CONCLUSIONS

These data indicate that hepatic resection is the first choice for treating HCC in CS I patients, and that PEIT or PMCT is preferable for CS II patients.

Atomic force microscopy with carbon nanotube probe resolves the subunit organization of protein complexes

Among many scanning probe microscopies, atomic force microscopy (AFM) is a useful technique to analyse the structure of biological materials because of its applicability to non-conductors in physiological conditions with high resolution. However, the resolution has been limited to an inherent property of the technique; tip effect associated with a large radius of the scanning probe. To overcome this problem, we developed a carbon nanotube probe by attaching a carbon nanotube to a conventional scanning probe under a well-controlled process. Because of the constant and small radius of the tip (2.5-10 nm) and the high aspect ratio (1:100) of the carbon nanotube, the lateral resolution has been much improved judging from the apparent widths of DNA and nucleosomes. The carbon nanotube probes also possessed a higher durability than the conventional probes. We further evaluated the quality of carbon nanotube probes by three parameters to find out the best condition for AFM imaging: the angle to the tip axis; the length; and the tight fixation to the conventional tip. These carbon nanotube probes, with high vertical resolution, enabled us to clearly visualize the subunit organization of multi-subunit proteins and to propose structural models for proliferating cell nuclear antigen and replication factor C. This success in the application of carbon nanotube probes provides the current AFM technology with an additional power for the analyses of the detailed structure of biological materials and the relationship between the structure and function of proteins.

Coexistence of primary biliary cirrhosis and myasthenia gravis: a case study

We present a case that suggests a relationship between primary biliary cirrhosis and myasthenia gravis. A 43-year-old Japanese woman was admitted to the Nagoya City University Medical School, First Department of Internal Medicine with abnormal liver function in August 1991. She had had ptosis of the right eye since 1990. She had not been treated for liver disease. Ptosis of the right eye and hepatomegaly were present. Serum laboratory examinations revealed elevated biliary enzymes and IgM levels; tests were positive for antimitochondrial antibody and antiacetylcholine antibody. Liver histology revealed chronic non-suppurative destructive cholangitis and led to a diagnosis of primary biliary cirrhosis. The tensilon test was positive. Electromyography with repetitive motor nerve stimulation revealed a neuromuscular junction defect; i.e., the primary characteristic of myasthenia gravis. The patient was diagnosed with myasthenia gravis. Although the development of myasthenia gravis has previously been reported in patients with primary biliary cirrhosis during D-penicillamine administration, this is a very rare case of the coexistence of both diseases before such treatment.

The cell biological application of carbon nanotube probes for atomic force microscopy: comparative studies of malaria-infected erythrocytes

We describe the first cell biological application of carbon nanotube (CN) probes for atomic force microscopy studies. Topographic and phase images were collected from Plasmodium falciparum malaria-infected erythrocytes using both TappingMode Etched Silicon Probes (TESP probe) and CN probes. We estimate that the lateral resolution of a CN probe-generated topographic image is at least four-fold higher than that of the TESP probe. Carbon nanotube probe-generated phase images of P. falciparum-induced knobs on the surface of erythrocytes also show a markedly higher lateral resolution than comparable TESP probe-generate phase images of the same area. We conclude that CN probes are useful for cell biological atomic force microscopy studies and should play an increasingly important role in the future of this evolving discipline.

Endoscopic injection sclerotherapy for esophagogastric variceal bleeding in children with biliary atresia

BACKGROUND/AIMS

To determine the safety and effectiveness of endoscopic injection sclerotherapy (EIS) for children with biliary atresia.

METHODOLOGY

Subjects were 7 patients with biliary atresia with esophagogastric varices and variceal bleeding. Intravariceal injection using 5% ethanolamine oleate was performed under fluoroscopy until varices were eradicated.

RESULTS

Endoscopic examination revealed that bleeding occurred in the junctional gastric varices in most of the cases. The mean number of EIS sessions required for obliteration of the varices was 2.3. In the observation period (mean: 21 months), recurrent esophagogastric varices occurred in 2 patients. One had variceal bleeding that was treated successfully by additional EIS. There were no severe complications associated with EIS.

CONCLUSIONS

EIS under fluoroscopy was safe and effective for variceal bleeding in children with biliary atresia.

Is the blood flow in the left ventricle during the isovolumic relaxation period a useful parameter of left ventricular systolic and early diastolic performance?

Left ventricular (LV) early diastolic performance is determined by LV behavior in the late systole to early diastole and may relate to the physical potential of patients. Isovolumic relaxation flow (IRF) velocity was obtained by continuous Doppler echocardiography in the left ventricle from the apex in 26 patients with atypical chest pain and 63 patients with coronary artery disease (CAD) with or without prior myocardial infarction (MI) who underwent cardiac catheterization. In each patient, a time constant of LV relaxation (tau) was calculated from the LV pressure waves obtained by a catheter-tipped micromanometer. The LV end-systolic volume index was measured using contrast left ventriculography. IRF velocity in patients having CAD with prior MI (24.8 +/- 5.4 cm/s) was significantly less than in those with atypical chest pain (41.2 +/- 9.6 cm/s). It was also significantly less than in patients having CAD without prior MI (37.3 +/- 6.8 cm/s). IRF velocity significantly correlated with the time constant tau (r = -0.42, p < 0.001) and LV end-systolic volume index (r = -0.84, p < 0.001). This study indicates that IRF velocity obtained by continuous Doppler echocardiography in the left ventricle provides important information regarding LV systolic performance and early diastolic performance.

Differentiation of abnormal relaxation pattern with aging from abnormal relaxation pattern with coronary artery disease in transmitral flow with the use of tissue Doppler imaging of the mitral annulus

An abnormal relaxation pattern in transmitral flow velocity waveforms has been observed in older healthy subjects as well as in patients with heart disease. Accordingly, we investigated whether the hemodynamic differences between patients with coronary artery disease (CAD) with an abnormal relaxation pattern in transmitral flow (ratio of E-wave to A-wave velocities < 1.0) and healthy older subjects with an abnormal relaxation pattern can be distinguished with the use of mitral annular velocity (MAV) during early diastole. We measured MAV in the longitudinal direction of the heart during early diastole by M-mode color tissue Doppler imaging in 24 patients with atypical chest pain (defined as healthy subjects in this study) and 70 patients with CAD who underwent cardiac catheterization. In all patients a time constant of left ventricular pressure decay (tau) and the left ventricular (LV) end-systolic volume index were also measured. Twenty-one healthy subjects and 59 patients with CAD had an abnormal relaxation pattern in their transmitral flow. The age, heart rate, mean blood pressure, and ratio of E-wave to A-wave velocities were not different between the two groups. However, the tau was longer and the LV end-systolic volume index was greater in patients who had an abnormal relaxation pattern with CAD than in healthy subjects with an abnormal relaxation pattern. The MAV during early diastole was lower in the former than in the latter (5.8 +/- 1. 9 vs 9.8 +/- 1.9 cm/s, P <.001). Mitral annular velocity during early diastole by M-mode color tissue Doppler imaging can detect the differences in LV relaxation and LV systolic performance between the abnormal relaxation pattern with CAD and the physiologically abnormal relaxation pattern with aging, providing further information regarding the meaning of an LV abnormal relaxation pattern.

Takayasu's arteritis accompanied with massive pericardial effusion--a case report

A 40-year-old woman who had been treated for Takayasu's arteritis was admitted to the hospital with fever, fatigue, malaise, and severe chest pain. Computed tomography of the chest demonstrated massive pericardial effusion and bilateral pleural effusion. In laboratory data, the C-reactive protein was high at 22.0 mg/dL, and erythrocyte sedimentation rate was also high at 80 mm/hr. The diagnosis was pericarditis with a recurrence of the systemic inflammatory process of Takayasu's arteritis. The patient was treated with methylprednisolone pulse therapy. Her massive pericardial effusion disappeared without pericardiocentesis.

Coadministration of basic fibroblast growth factor and sucrose octasulfate (sucralfate) facilitates the rat dorsal flap survival and viability

The effective use of local growth factors and cytokines may replace the lengthy staged surgical delay process. We tested the efficacy of basic fibroblast growth factor (bFGF) coadministered with sucralfate (sucrose octasulfate) on the rat dorsal flap model. A total of 76 male Wistar rats were used in this experiment. Four groups of the animals were divided. Group 1 (n = 5) was the vehicle control (saline soaked), group 2 (n = 5) was sucrose octasulfate soaked (100 microg/ml, 1 ml), group 3 (n = 5) was bFGF soaked (1 microg/ml, 1 ml), and group 4 (n = 5) was both bFGF and sucrose octasulfate soaked. All agents were soaked equally in Gelfoam. The flap survival measured by the quantitative computer-assisted morphologic analysis was significantly improved by day 5 postoperatively in the combined administration group compared with the vehicle control (81 and 53 percent, respectively; p < 0.05). In lead oxide-gelatin microangiography, there was enhanced pedicle vessel formation observed as well as the extended vessel sprouting up to very close to the distal end in combined group on day 5. The endogenous bFGF mRNA expressions shown by reverse transcriptase-polymerase chain reaction were detected in all four groups. The angiogenesis indicated by alpha-smooth muscle actin immunopositivity was significantly more enhanced in the combined group than the vehicle control (37.3 and 19.4, respectively; p < 0.01). In the combined group, there was stronger immunopositivity for bFGF in epidermis and hair follicles observed, and more notably bFGF-immunopositive dermal fibroblasts were evident. Thus, coadministration of bFGF and sucralfate markedly facilitates the rat dorsal flap survivability by enhancing the bFGF expression and angiogenesis.

Evaluation of left ventricular early diastolic performance by color tissue Doppler imaging of the mitral annulus

A noninvasive assessment of left ventricular (LV) diastolic performance by tissue Doppler imaging was performed in 56 patients (8 patients with atypical chest pain, 42 with coronary artery disease with a previous myocardial infarction, and 6 without a previous myocardial infarction) who underwent cardiac catheterization. Mitral annular velocity (MAV) during early ventricular diastole was obtained by M-mode color tissue Doppler imaging at the posterior corner of the mitral annulus. In each patient, the negative peak of the first derivative of LV pressure decay (peak -dP/dt) and a time constant of LV relaxation (tau) were calculated from the LV pressure waves obtained by a catheter-tip micromanometer. LV end-systolic volume index was measured from contrast left ventriculography. MAV during early diastole was significantly correlated with tau (r = -0.73, p <0.001), peak -dP/dt (r = 0.58, p <0.001), and LV end-systolic volume index (r = -0.63, p <0.001). On multivariate regression analysis with MAV during early diastole, tau and LV end-systolic volume index were selected as prime determinants (r = 0.80, p <0.001). These findings suggest that MAV during early diastole has a direct relation to LV elastic recoil as well as to LV relaxation. MAV during early diastole gives important information regarding LV behavior in late systole to early diastole where LV early diastolic performance is determined.

Extent of myocardial damage in regions with reverse redistribution at 3 h and at 24 h on 201Tl SPET: evaluation based on regional myocardial oxidative metabolism

Reverse redistribution (RRD) of 201Tl is often observed in patients with recent myocardial infarction. However, the difference in the extent of myocardial damage between regions with 3-h RRD and those with 24-h RRD remains unknown. Accordingly, we investigated RRD from the standpoint of myocardial oxidative metabolism. Carbon-11 (11C) acetate dynamic myocardial PET scanning was performed at rest in 14 patients with recent myocardial infarction, and the clearance rate constant (Kmono) of 11C-acetate was calculated in 6-7 ROIs on the transaxial image in each patient using a monoexponential fit as an index of myocardial oxidative metabolism. Exercise 201Tl myocardial SPET was also performed. Ninety-two regions corresponding to the PET study were then classified based on the findings of transaxial 201Tl SPET imaging; that is, regions with reverse redistribution, regions with severely decreased 201Tl activity or no 201Tl activity on the 24-h delayed images, and regions with normal 201Tl activity throughout the study. Kmono in regions with reverse redistribution (0.051 +/- 0.009 min-1) was significantly lower than that in regions with normal 201Tl activity throughout the study (0.066 +/- 0.011 min-1) (P < 0.001) but significantly higher than that in regions with severely decreased or no 201Tl activity on the 24-h delayed images (0.037 +/- 0.003 min-1) (P < 0.001). Percent Kmono (i.e. Kmono in region with RRD/the mean of Kmono in all regions with a normal 201Tl SPET result) was significantly lower in the 3-h RRD regions (81.3 +/- 6.3%) than in the 24-h RRD regions (87.6 +/- 6.1%) (P < 0.05). Impairment of myocardial oxidative metabolism is observed in regions with RRD, suggesting that RRD corresponds to mild myocardial damage. Reverse redistribution on 24-h delayed images may indicate much milder myocardial damage compared with RRD on 3-h delayed images.

[Retropharyngeal abscess in an adult and an elderly woman]

Retropharyngeal abscess is reported to be decreasing in frequency in recent years. We report two cases of retropharyngeal abscess that were diagnosed within four years in Department of Otorhinolaryngology, Gifu University Hospital. Case 1 was a 36-year-old male who was suggested to have an abscess as primary infection and case 2 was a 71-year-old female whose abscess seemed to be a secondary infection following unknown primary infection. Endoscopic or open neck drainage as well as antibacterial chemotherapy mainly with combinations of flomoxef and clindamycin in the case 1 and piperacillin and clindamycin in the case 2 was successfully carried out. They were discharged an 15-day and 24-day after operation in the cases 1 and 2, respectively. A 30 min. culture after sample collection on operation demonstrated aerobe-anaerobe mixed infection in both cases; three aerobes and four anaerobes in the case 1 and three aerobes and two anaerobes in the case 2. These results suggest that retropharyngeal abscess may be a complicated infection involving more bacterial species than has been commonly believed. Measuring susceptibility of isolates to antimicrobial agents, a strain of Capnocytophaga sp. and a strain of anaerobic gram-negative rod were highly resistant to piperacillin, cefroxine and ofloxacin. It is important for adequate antibacterial chemotherapy to grasp the bacteriology of retropharyngeal abscess and analyze susceptibility of antimicrobial agents.

Two mechanisms by which ATP depletion potentiates induction of the mitochondrial permeability transition

The present and a previous study [J. W. Snyder, J. G. Pastorino, A. M. Attie, and J. L. Farber, Am. J. Physiol. 264 (Cell Physiol. 33): C709-C714, 1993] define two mechanisms whereby ATP depletion promotes liver cell death. ATP depletion and cell death are linked by the mitochondrial permeability transition (MPT). Mitochondrial deenergization promotes the MPT, and ATP maintains a membrane potential by reversal of ATP synthase. With an increased influx of Ca2+ induced by the ionophore A-23187, oligomycin depleted the cells of ATP without loss of the mitochondrial membrane potential and further elevated the intracellular Ca2+ concentration. Cyclosporin A (CyA) prevented the accompanying cell killing. Fructose also preserved the viability of the cells. With the increased cytosolic Ca2+ imposed by A-23187, viability is maintained by ATP-dependent processes. Upon depletion of ATP, Ca2+ homeostasis cannot be maintained, and the MPT is induced. Rotenone also depleted the cells of ATP, and A-23187 accelerated the loss of the mitochondrial membrane potential occurring with rotenone alone. CyA and fructose prevented the cell killing with rotenone and A-23187. Oligomycin did not prevent this action of fructose. We conclude that ATP is needed to maintain Ca2+ homeostasis to prevent the MPT and the resultant liver cell death. ATP is also needed to maintain mitochondrial energization when electron transport is inhibited.

Estimation of pulmonary capillary wedge pressure from M-mode mitral echograms

We investigated whether the isovolumic relaxation time (IRT) and an interval from the start of opening to the maximal amplitude of the anterior mitral leaflet in early diastole (D-E interval) would be useful predictors of the pulmonary capillary wedge pressure (PCWP). We recorded M-mode mitral echograms and phonocardiograms in 33 patients (aged 38-70 years) with acute myocardial infarction (AMI) in the coronary care unit and in 34 patients (aged 40-75 years) with prior myocardial infarction (OMI) during cardiac catheterization. All patients underwent the insertion of a flow-directed pulmonary artery catheter to obtain the PCWP. We measured the IRT and the D-E interval from the phonocardiograms and the M-mode echograms. There was no significant correlation between the IRT and the mean PCWP (mPCWP) in patients with AMI and in patients with OMI. The D-E interval was significantly and inversely correlated with the mPCWP (r = -0.91, p <0.0001) in all patients. The regression equation was mPCWP = -0.42 x (D-E) +47.9. The D-E interval of < or = 75 ms indicated a high mPCWP (mPCWP > or = 18 mm Hg) with high sensitivity (96%) and specificity (88%). The derived equation was tested in a prospective group of 32 additional patients (aged 43-75 years). A significant correlation was observed between the predicted and measured mPCWP (r = 0.91, p <0.0001). Thus, the PCWP can be estimated by using the D-E interval derived from M-mode mitral echograms in patients in the coronary care unit and in patients with chronic heart disease.

Pituitary-directed leukemia inhibitory factor transgene forms Rathke's cleft cysts and impairs adult pituitary function. A model for human pituitary Rathke's cysts

Leukemia inhibitory factor (LIF) and LIF receptors are expressed in adenohypophyseal cells and LIF regulates pituitary hormone transcription and cell replication in vitro. Therefore, transgenic mice expressing pituitary-directed LIF driven by the rat growth hormone (GH) promoter were generated to evaluate the impact of LIF on pituitary development. Three founders were established with diminished linear growth and body weight (57-65% of wild type [WT]), and intense anterior pituitary LIF immunoreactivity. Cystic cavities observed in pituitary anterior lobes were lined by cuboidal, ciliated epithelial cells, focally immunopositive for cytokeratin and S-100 protein and immunonegative for adenohypophyseal hormones. Transgenic pituitaries showed decreased GH (40%) and prolactin (PRL) (26%) cells, and decreased GH and PRL mRNAs by in situ hybridization. ACTH cells increased 2.2-fold, whereas gonadotrophs and thyrotrophs were unchanged. Serum GH was undetectable (< 0.78 ng/ml), PRL levels were one third of WT (P < 0.05), IGF-I levels were 30% of WT (P < 0. 001), and T4 was normal. 10 human pituitary Rathke's cysts studied all showed conclusive LIF immunoreactivity in cyst-lining cells. Thus, intrapituitary murine LIF overexpression causes cystic invaginations from the anterior wall of Rathke's cleft, suggesting failed differentiation of Rathke's epithelium to hormone-secreting cells. Arrested murine pituitary maturation with formation of pituitary Rathke's cleft cysts, GH deficiency, and short stature provide a model to study human Rathke's cyst pathogenesis.

Comparative effects of volume loading on pulmonary venous flow in dogs with normal heart and with myocardial ischemia

The influences of cardiac loading conditions and left ventricular performance on pulmonary venous flow are poorly understood. The authors studied the effects of volume loading on the pattern of pulmonary venous flow in normal and ischemic hearts. Thirteen anesthetized dogs were equipped with a transit-time ultrasonic flow probe around the left upper pulmonary vein. In 6 of the dogs, the left anterior descending artery was ligated to induce myocardial ischemia. The remaining 7 dogs had normal hearts. Heart rate was fixed at 110 beats/minute by right atrial pacing. Dextran was infused from the femoral vein until mean left atrial pressure increased 3 mm Hg above the baseline value in both groups. In normal heart, systolic pulmonary venous flow volume (SI) increased significantly, but early diastolic flow volume (DI) did not show a significant change during volume loading. The ratio of SI/DI increased significantly (1.12 +/- 0.34 vs 2.11 +/- 0.49, P < 0.05). After ligation of the left anterior descending artery, the SI and DI decreased significantly. The ratio of SI/DI did not show a significant change (0.88 +/- 0.32 vs 0.87 +/- 0.30, ns). In dogs with myocardial ischemia, volume loading caused increases in the SI and DI. However, no significant change was observed in the ratio of SI/DI (0.87 +/- 0.30 vs 0.97 +/- 0.36, ns). These findings demonstrate that left ventricular performance influences the alteration in pulmonary venous flow pattern that is caused by systemic volume loading.

Leukemia inhibitory factor (LIF) induces acute adrenocorticotrophic hormone (ACTH) secretion in fetal rhesus macaque primates: a novel dynamic test of pituitary function

Leukemia Inhibitory Factor (LIF), a pituitary cytokine, and LIF receptors are expressed in human fetal and adult adenohypophyseal cells. LIF induces adrenocorticotropin hormone (ACTH) secretion in vitro and potently synergizes with both corticotropin-releasing hormone (CRH) and cAMP-induced pro-opiomelanocortin (POMC) transcription. We therefore investigated the effects of intra-carotid administration of recombinant human LIF to chronically catheterized fetal non-human primates. LIF induced fetal monkey ACTH secretion in a time- and dose dependent manner. Maximal ACTH induction (12-fold) was achieved with 100 micrograms/kg after 60 minutes (p < 0.01). CRH (10 micrograms/kg) also induced ACTH secretion 4.8-fold at 60 minutes. Co-injection of LIF (50 micrograms/kg) and CRH (10 micrograms/kg) synergistically induced ACTH levels in a time-dependent manner up to 23-fold after 60 minutes. Thus, LIF alone induces ACTH secretion and LIF acts in synergy with CRH in vivo. As LIF is expressed early in human fetal pituitary development, and potentiates corticotroph function both in vitro and in vivo, this immuno-regulatory cytokine may be useful for clinical testing of the hypothalamic-pituitary-adrenal axis.

Simultaneous evaluation of the Doppler-derived transmitral flow velocity waveform and left ventricular isovolumic relaxation time in patients with coronary artery disease

We studied the usefulness of simultaneous evaluation of the Doppler-derived transmitral flow velocity waveform and left ventricular isovolumic relaxation time (IRT) in patients with coronary artery disease (CAD). Subjects consisted of 26 healthy volunteers, 54 patients with prior myocardial infarction (MI), and 27 patients with CAD but without prior MI. IRT was measured as the time from the beginning of the aortic valve closure sound to the onset of transmitral flow. Peak filling velocity during early diastole (E-wave velocity), peak filling velocity during atrial contraction (A-wave velocity), and IRT were compared among the three groups. No significant difference in A-wave velocity was found among these groups. Whereas E-wave velocity was significantly lower and IRT was significantly longer in patients with CAD but without prior MI than in healthy subjects, no significant differences in E-wave velocity or IRT were observed between patients with prior MI and healthy subjects. We then divided the patients with prior MI into two subgroups, one consisting of 45 patients with mean pulmonary capillary wedge pressure (mPCWP) < 16 mm Hg and the other consisting of 9 patients with mPCWP > or = 16 mm Hg. There was no significant difference in A-wave velocity between the two subgroups and healthy subjects. E-wave velocity was significantly lower in patients with MI and lower mPCWP than in healthy subjects, however, no significant difference in E-wave velocity was found between the patients with MI and higher mPCWP and the healthy subjects. On the other hand, IRT was significantly longer in those with lower mPCWP and significantly shorter in those with higher mPCWP than in healthy subjects. In conclusion, normal transmitral flow velocity waveform with short IRT suggests a 'pseudonormal' pattern due to elevated mPCWP in patients with CAD.

Usefulness of Ga-67 brain SPECT in patients with CNS malignant lymphoma

The efficacy of Ga-67 SPECT imaging of CNS malignant lymphoma was investigated in 14 studies of 11 patients. As compared with planar images, the SPECT imaging improved the detectability of the focus of CNS malignant lymphoma. All untreated cases showed L/N ratios higher than 3.0. And the L/N ratios also changed according to remission or relapse of CNS malignant lymphoma.