The role of middle ear effusions and epidermal growth factor in cholesteatoma formation in the gerbilline temporal bone

To study the process of aural cholesteatoma formation, we used gerbilline temporal bones to examine histologically the early stages of spontaneous cholesteatomas associated with experimentally induced otitis media with effusion (OME) following electric cauterizations of the eustachian tube. Epidermal growth factor (EGF) was then localized immunohistochemically in the pars flaccida of normal ears and the forming spontaneous cholesteatomas. Findings in the ears with the early spontaneous cholesteatomas were effusion inside the pars flaccida and hypertrophy and hyperkeratosis of the pars flaccida. Findings in the ears with experimental OME involved an effusion in the whole middle ear cavity as well as hypertrophy and hyperkeratosis in both the pars flaccida and pars tensa. The incidence of ear drum changes was higher in the experimental OME group than in control animals without cauterization. EGF was localized in the mucous layer of normal drums, the mucous layer and lamina propria of drums with hypertrophy alone, and all layers in drums with hypertrophy and hyperkeratosis. EGF was especially positive in the cytoplasms of transformed cuboidal cells. These findings suggest that EGF within the transformed mucous layer may play an important role as a biochemical factor in developing cholesteatomas.

Variation of urinary pH and bicarbonate concentrations of students in metropolitan and rural areas of Japan

Changes in urinary pH and bicarbonate levels were studied in urine collected before and after final examinations taken by 91 medical students (65 males, 26 females) in Tokyo and from 87 students (73 males, 14 females) in Kanazawa, a rural municipality. Bicarbonate levels and pH in the urine of students in both cities increased significantly after attending 2 h of final examinations. The highest pH value and highest bicarbonate level were 7.66 and 80.3 mM, respectively, found in the urine of a student in Kanazawa. Urinary pH and bicarbonate levels averaged 6.48 and 11.1 mM, respectively, for students in Tokyo and 6.26 and 8.91 mM, respectively, for students in Kanazawa. Given that the concentrations of carbon dioxide in the air of the classrooms in both cities increased drastically during the final examinations (i.e., from 700 ppm to 1 200 ppm in Tokyo and from 700 ppm to 1 500 ppm in Kanazawa), it appears that the increases in urinary pH and bicarbonate levels were correlated with the increase of carbon dioxide (known to be convertible to bicarbonate in blood) in the rooms. This was also supported by the increase in urinary pH and bicarbonate levels found in urine collected from 20 students who stayed in a cinema for 3 h, at which location carbon dioxide levels in air reached 1 200 ppm.

New design of N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) lung imaging in the patient with lung cancer

N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) was injected intravenously into primary non small cell lung carcinoma patients (n = 17). The average pixel count ratios of the cancerous area to the whole lung was measured in the initial and delayed images. In the initial image, this ratio was less than 1.0 for the entire group of patients, and was thought to reflect decreased blood flow in the cancerous tissues. The rate of counts within a ROI in the delayed image to counts in the same ROI in the initial image was also calculated and called the remain rate. The remain rate (delayed count/initial count) was significantly higher in the cancerous area than in the whole lung (0.65 +/- 0.30, median 0.62, 0.38 +/- 0.05, median 0.38, p < 0.01). This observation was thought to be due to a relative decrease in the blood flow and the accumulation of IMP, which forms pools within the alveolar spaces of the cancerous areas. The image prepared with the remain rate revealed a hot image in the cancerous regions, even when this was not apparent in the delayed image. The remain rate image may therefore be useful in the identification of cancerous areas in lung tissue if it is used in comparison with the initial image.

Lipoproteins regulate C-type natriuretic peptide secretion from cultured vascular endothelial cells

We have shown that oxidized low-density lipoprotein (Ox-LDL) modulates various endothelial cell (EC) functions. C-type natriuretic peptide (CNP), the third member of the natriuretic peptide family to be discovered, is secreted from peripheral vascular ECs and regulates body fluid homeostasis, vascular tone, and vascular growth. This study was designed to investigate the effects of lipoproteins on CNP secretion from cultured ECs. Treatment of bovine carotid ECs with OX-LDL and its extracted lipids resulted in a concentration-dependent suppression of the spontaneous and transforming growth factor-beta 1-stimulated secretion CNP. Native LDL, its extracted lipids, and acetylated LDL were inactive. OX-LDL depleted of its amphiphilic lipids, which was prepared by incubation with defatted albumin, lost its suppressive effect on CNP secretion. 7-Ketocholesterol, one of the amphiphilic lipids in OX-LDL that is transferable from OX-LDL to defatted albumin, suppressed CNP secretion by ECs, thus mimicking the effect of OX-LDL. Coincubation with high-density lipoprotein (HDL), which alone had no effect on CNP release, significantly prevented OX-LDL-induced inhibition of CNP secretion by ECs. Analysis by thin-layer chromatography demonstrated that oxysterols, including 7-ketocholesterol, in OX-LDL were transferred from OX-LDL to HDL during coincubation of these two lipoproteins. These results indicate that OX-LDL suppresses CNP secretion from ECs by 7-ketocholesterol or other transferable hydrophilic lipids in OX-LDL, and the suppressive effect of OX-LDL is reversed by HDL. Lipoproteins thus may regulate CNP secretion from the endothelium of atherosclerotic arteries.

Altered cardiovascular responses to purinergic A2 stimulation in the nucleus tractus solitarius of spontaneously hypertensive rats

OBJECTIVE

To investigate the cardiovascular effects of adenosine A2 receptor stimulation in the nucleus tractus solitarius and whether these effects are altered in hypertension.

DESIGN AND METHODS

Ten- or 11-week-old spontaneously hypertensive rats (SHR) or Wistar-Kyoto (WKY) rats were anaesthetized with urethane. Adenosine (100 ng) or adenosine A2 agonist (2-octynyladenosine, 5 ng) were micro-injected (50 nl) into the nucleus tractus solitarius. Blood pressure and heart rate were measured from a femoral artery. Sympathetic nerve activity was recorded from the abdominal splanchnic nerve.

RESULTS

Blood pressure, heart rate and sympathetic nerve activity were consistently decreased after the micro-injection of adenosine into normotensive rats. Changes from the baseline in blood pressure, heart rate and sympathetic nerve activity were significantly smaller in SHR than in WKY rats (blood pressure: SHR -5.6 +/- 2.1% versus WKY rats -20.0 +/- 2.1%; heart rate: SHR -5.4 +/- 0.88% versus WKY rats -9.2 +/- 2.3%; sympathetic nerve activity: SHR -5.5 +/- 1.1% versus WKY rats -21 +/- 2.8%). Micro-injection of an A2 agonist into the nucleus tractus solitarius also decreased blood pressure and heart rate, and those responses were not inhibited by pretreatment with an adenosine A1-specific antagonist. The response induced by micro-injection of A2 agonist into the nucleus tractus solitarius was significantly smaller in SHR than in WKY rats, whereas the changes in heart rate did not differ statistically (blood pressure: -23.4 +/- 4.7% versus -10.8 +/- 2.1%; heart rate: -12.1 +/- 1.2% versus -13.6 +/- 2.1%).

CONCLUSION

The present results suggest that stimulation of adenosine A2 receptors in the nucleus tractus solitarius decreases both blood pressure and inhibitory sympathetic nerve activity and that those inhibitory responses to adenosine in the nucleus tractus solitarius are deranged in SHR.

Suppurative lesions without prominent epithelioid cell response in abscess-forming granulomatous lymphadenitis

To clarify the clinicopathological significance of the suppurative lesions without an epithelioid granulomatous response (SLs without Ep) in lymph nodes and their relationship to abscess-forming granulomatous lymphadenitis (AGL) and cat scratch disease (CSD), 10 cases were assessed clinicopathologically and immunohistologically. SLs without Ep were located in the subcapsular sinus, paracortical area and medullary cords, but not in the germinal centers. The microabscesses were surrounded by collections of monocytoid B-lymphocytes (MBLs), histiocytes without epithelioid features, neutrophils, small lymphocytes and small numbers of plasma cells. The majority of the MBLs seen in the SLs without Ep were of the large cell type. The histological triad of toxoplasmic lymphadenitis, i.e., reactive follicular hyperplasia, small clusters of epithelioid cells and aggregates of MBLs, were also seen in all cases. Some of the clinical and pathological findings in our 10 cases were characteristic of CSD, i.e., (1) cat exposure before the lymphadenopathy was in four of the 10 cases, (2) occurrence in autumn and winter months in all cases, (3) typical suppurative granulomas surrounded by palisaded epithelioid cells were in four of the 10 cases, and (4) Warthin-Starry silver stain-positive bacteria were detected in seven of the 10 cases. The results of our study suggest that SLs without Ep are an early stage of CSD.

Dominant role of the second heat shock element in expression of the HSP70-1 gene in rat liver after whole body hyperthermia

We investigated the regulatory expression of the HSP70-1 gene in rat liver after whole body hyperthermia (rectal temperature of 42 degrees C for 30 min). After heat treatment, HSP70-1 mRNA showed a peak at 1 h, and its protein product began to increase at 3 h. Under these conditions, we identified cis-acting elements involved in the regulatory expression of the HSP70-1 gene by in vivo genomic footprinting. We observed that the second heat shock element (HSE-2; -201 to -178) was clearly protected from methylation by dimethyl sulfate in parallel with the increase in HSP70-1 mRNA. On the contrary, the most proximal HSE-1 (-120 to -101) was protected only slightly. Furthermore, the flanking regions of HSE-2, that is, an NF-kappa B-like element on the upstream side and a GC box on the down-stream side were also protected simultaneously in accordance with the induced expression of the HSP70-1 gene. Gel mobility shift assays with nuclear extracts from rat liver at 30 min after heat treatment showed maximal DNA binding activity equally with oligonucleotides containing HSE-1 and HSE-2, respectively, and also demonstrated the participation of heat shock factor-1 (HSF1) in both cases. These results suggest that, in addition to HSF1, other regulatory factors might be involved in the dominant protection of HSE-2 in the promoter of the HSP70-1 gene in rat liver after whole body hyperthermia.

Cloning of the cDNA encoding a novel rat mast-cell proteinase, rMCP-3, and its expression in comparison with other rat mast-cell proteinases

A cDNA encoding a novel rat mast-cell proteinase (MCP) named rMCP-3 was successfully cloned and sequenced from the peritoneal cells of Lewis rats infected with the intestinal nematode Nippostrongylus brasiliensis by using the combination of reverse transcription-PCR and rapid-amplification-of-cDNA-ends ('RACE') methods. The cDNA was 979 bp long and included a 741 bp open reading frame. When the deduced amino acid sequence was compared with those of other known mast-cell proteinases, rMCP-3 was considered to be translated as a preproenzyme with a 19-amino-acid signal peptide, a two-amino-acid activation peptide and a 226-amino-acid mature enzyme. The amino acid identity in the mature enzyme was 52.9% and 55.1% with rMCP-1 and rMCP-2 respectively. The rMCP-3 mRNA was not detected in the peritoneal cells of mast-cell-deficient Ws/Ws rats, though it was strongly detected in those of littermate +/+ and Lewis rats, indicating the mast-cell origin of rMCP-3 In addition to being present in peritoneal mast cells, the rMCP-3 mRNA was strongly detected in the skin, tongue, and RBL2H3 rat basophilic leukaemia cells and weakly in the jejunum of N. brasiliensis-infected rats by RNA blot analysis using a rMCP-3 gene-specific probe. By reverse transcription-PCR, the rMCP-3 mRNA was also detected in the lung. While the expression of rMCP-1 and rMCP-2 are clearly restricted in connective-tissue mast cells and mucosal mast cells respectively, rMCP-3 was widely expressed in both types of mast cells with a predominance in connective-tissue mast cells.

Autoantibodies against 70-kDa heat shock proteins (HSP70) in allogeneic bone marrow transplant recipients

We report that autoantibodies against the 70-kDa heat shock protein family (HSP70) were detected in allogeneic bone marrow transplant recipients. Antibodies to HSP70 family proteins were detected in three out of 14 recipients of an allogeneic marrow graft but in none of the seven patients receiving autologous peripheral blood stem cell transplant (PBSCT). Immunoblotting analysis combined with two-dimensional SDS-PAGE revealed that these patients had antibodies to a constitutive 73-kDa/pI 5.5 heat shock protein (HSP73) and to a stress-inducible 72-kDa/pI 5.6 protein (HSP72). This is the first report, to our knowledge, describing the presence of autoantibody against HSP73 in allogeneic marrow transplant recipients. Our results may provide additional insight into the etiology and the pathophysiology of allogeneic transplant-related disorders.

Novel colorectal adenocarcinoma-associated 40- and 47-kDa protein antigens recognized by anti-60-kDa heat shock protein antibody

Expression of 40- and 47-kDa proteins recognized by anti-60-kDa heat shock protein antibody was investigated in colorectal adenocarcinoma tissue. In all cases of colorectal adenocarcinoma tissue (n = 9), 40- and 47-kDa proteins were detected by immunoblot analysis. However, expression of these two proteins was extremely low or was not expressed in control tissue. There was no correlation between the quantity of these two bands and histologic type or the location of the tumors. Our results first demonstrate the accumulation of structurally altered 60-kDa heat shock protein-associated antigens in carcinoma tissue and suggest that these two proteins could be a possible candidate for tumor-specific 60-kDa heat shock protein-related protein antigens.

The influence of arm movements on a vertical jump

The influence of arm lowering movements (ALM) on a vertical jump with all but the ankle joints immobilized was studied in five healthy volunteers. Subjects were instructed to rapidly lower both arms after takeoff when jumping from an initial position with the elbows flexed. They performed the jumps either with their hands empty or holding 4 kg dumbbells. ALM prolonged the time subjects were airborne, especially when holding the dumbbells. Protocol for the experiment required that subjects maintain maximum angular velocity of the ankle joint, vertical platform force, and electromyographic monitoring from the triceps surae muscle. Positive acceleration of the head increased in the ALM jumps, and became even more pronounced when the jumps were performed with dumbbells. This increase in head acceleration was inversely proportional to the downward acceleration of the hands. These results indicate that prolonging a vertical jump depends on ALM in the air.

Induction and intracellular localization of a 72-kDa heat shock protein in rat gastric mucosa after water-immersion stress

We investigated the expression and changes in the intracellular localization of a 72-kDa heat shock protein (HSP72) in rat gastric pyloric and fundic mucosa before and after water-immersion stress. Severe mucosal damage was found in the fundic mucosal area of the stomach after this stress. However, no mucosal lesion developed in the pyloric mucosal area. HSP72 in both the soluble and insoluble fractions of the pyloric and the fundic mucosal areas was significantly increased after water-immersion stress, peaking 6h after the initiation of the stress. The increase in HSP72 was more significant in the pyloric mucosal area than in the fundic mucosal area under both normal and stress conditions. The increase of HSP72 in the pyloric mucosal cells occurred prior to the formation of the mucosal lesions, whereas the increase of HSP72 in the fundic mucosal cells was observed after ulcer formation. An immunohistochemical study showed that HSP72 was constitutively expressed in the cytoplasm of the gastric mucosal cells, and that the intranuclear induction of HSP72 was remarkably intense in the pyloric mucosal cells, especially in the proliferative zone, compared with the fundic mucosal cells. Our results may suggest that HSP72 has an important cytoprotective function in gastric mucosal cells and that there is a "biophysical" difference between pyloric and the fundic mucosal cells.

Salivary and blood lactate after supramaximal exercise in sprinters and long-distance runners

This investigation examined the reproducibility of salivary lactate measurement in long-distance runners following a 3000-m run and compared the salivary and blood lactate concentrations in sprinters and long-distance runners following a 400-m run. There was no significant difference in salivary and blood lactate between the first and second 3000-m run test. The peak salivary and blood lactate following a 400-m run was higher in sprinters than in long-distance runners. There was a significant relationship between the peak lactate of saliva and that of blood following a 400-m run. The results showed that the salivary lactate following exercise was reproducible and the salivary lactate concentration may serve as a relevant indicator in determining which have a higher lactate production.

Molecular cloning of mouse intestinal trefoil factor and its expression during goblet cell changes

A cDNA encoding mouse intestinal trefoil factor (mITF) was successfully cloned and sequenced from the small intestine of C57BL/6 mouse by using the combination of reverse transcription-PCR and rapid amplification of cDNA ends methods. The gene was, similar to rat and human ITFs, mainly expressed in the small and large intestine. The mITF expression was up-regulated during the recovery phase after depletion of goblet cells in acetic acid-induced colitis. On the other hand, the expression in the jejunum was not altered, while goblet cell hyperplasia was induced by Nippostrongylus brasiliensis infection. These results suggest that the mITF expression did not simply correlate with the number of goblet cells. The mITF may play an important role in the maintenance and repair of mucosal function of the rectum. Additionally, the mITF in the jejunum may play a role in alteration of the physicochemical nature of goblet cell mucins, thereby affecting the establishment of intestinal helminths.

CT and pathological correlation of pulmonary sarcoidosis

In CT the presence of mediastinal or hilar lymphadenopathies and thickened bronchovascular bundles are landmarks for the diagnosis of pulmonary sarcoidosis. The major CT findings for parenchymal involvement are thickened bronchovascular bundles, large parenchymal nodules, pleural or subpleural nodules, ground-glass opacities, local lung volume loss (distortion of the lung parenchyma), and microscopic and macroscopic honeycombing. The thickened bronchovascular bundles correspond histologically to granulomas, either with or without perigranulomatous fibrosis in the connective tissue sheath around the pulmonary vessels and airways. Conglomerate granulomas are represented on CT by high-attenuation nodules, and the ground-glass opacities are caused by the summation of a number of small granulomas in the interstitium.

CT of pulmonary tuberculosis

CT scans in patients with primary tuberculosis commonly show lymphohematogenous spread of the disease, whereas those of postprimary (reactivation) tuberculosis commonly show bronchogenic spread. High-resolution CT (HCRT) is extremely helpful in understanding pathomorphological changes, mode of spread of the disease, and sequential morphological change after antituberculous chemotherapy, and possibly in diagnosing activity of the disease. Centrilobular 2- to 4-mm nodules or branching linear lesions representing intrabronchiolar and peribronchiolar caseation necrosis are the most common findings of early bronchogenic spread of tuberculosis. The 2- to 4-mm centrilobular nodules may coalesce to form 5- to 8-mm nodules or lobular consolidation. Cavitation usually begins at the central portion of a lobule around the bronchioles. Resolution of the tuberculous lesions occurs with antituberculous chemotherapy, resulting in varying degrees of fibrosis, bronchovascular distortion, emphysema, and bronchiectasis. HRCT may show both paracicatricial irregular emphysema and lobular emphysema. CT findings of early miliary dissemination commonly include ground-glass opacification with barely discernible nodules that show discrete miliary nodules thereafter. CT also is useful in the evaluation of long-standing destructive pulmonary lesions and tracheobronchial tuberculosis.

A physical fitness model of older adults

Physical fitness for young people is viewed as a multidimensional construct, in that it consists of specific components such as strength, mobility, balance, flexibility, and stamina. This study examined whether this structure underlying physical fitness is also relevant to older adults. A 10-item performance test, which was assumed to assess six components of physical fitness, was administered to 69 healthy volunteers ranging in age from 61 to 83 years. A covariance structure model was applied to the test data: the second-order factor was Physical Fitness, and the first-order factors were Strength, Walking, Balance, Flexibility, Stamina, and Manual Speed which were assumed to be measured based on the ten observed variables. Goodness-of-fit index (GFI) of the model was acceptable (GFI = 0.93). While four factors relating to basic motor performances (Strength, Walking, Balance, and Manual Speed) had loadings more than 0.62 to Physical Fitness, Flexibility and Stamina had less than 0.35. It was suggested for elderly people that strength, mobility, balance, and speed components of physical fitness were highly correlated and explainable by a single factor, while flexibility and cardiorespiratory endurance were to be measured by use of specific measures.

[Radiotherapy for carcinoma of the esophagus in aged patients]

One hundred fifty-four patients with esophageal carcinoma were treated with either irradiation alone or irradiation combined with surgery at the University of Occupational and Environmental Health Hospital between January 1980 and February 1992. The number of patients 75 years old and older was 25. In patients 74 years old and younger, the overall five-year survival rate by Kaplan-Meier method was 24.5%. The survival rate was best in the patients who were treated by a combination of irradiation and surgery. In patients 75 years old and older, the one-year survival rate was 59%, and the three-year rate was 20%. Aged patients had a tendency to be worse in performance status, and there was no correlation between treatment modality and survival time. We conclude that radiotherapy is useful for treating esophageal cancer in aged patients particularly when maintenance of the quality of life is considered.

Isoenzymes of cyclic nucleotide phosphodiesterase in the human aorta: characterization and the effects of E4021

In extracts of the human aorta, five isoenzymes of cyclic nucleotide phosphodiesterase, namely, phosphodiesterase I, phosphodiesterase II, phosphodiesterase III, phosphodiesterase IV and phosphodiesterase V, were identified exclusively in the cytosolic fraction, and no phosphodiesterase activity was detected in the particulate fraction. Phosphodiesterase V and phosphodiesterase I were the major cGMP-hydrolyzing enzymes in the human aorta. A novel vasorelaxant, sodium 1-[6-chloro-4-(3,4-methylenedioxybenzyl)aminoquinazolin-2-yl ]piperidine-4- carboxylate sesquihydrate (E4021), relaxed prostaglandin F2 alpha-precontracted strips of human pulmonary artery with an ED50 value of 0.5 microM. E4021 potently and highly selectively inhibited the activity of phosphodiesterase V from human aorta with a Ki value of 2.4 nM. These results suggest that there is a unique distribution of phosphodiesterase isoenzymes in the human aorta and that inhibitors of phosphodiesterase V might be useful as a new type of vasodilator in the treatment of clinical disorders.

E-cadherin and urokinase-type plasminogen activator tissue status in gastric carcinoma

BACKGROUND

E-cadherin (ECD) is known to be an invasion suppressor gene, and urokinase-type plasminogen activator (uPA) plays a central role in infiltration of solid cancers.

METHODS

To elucidate the relationship between expression of these factors and metastasis in patients with gastric cancer, the authors examined immunohistochemically a combination analysis of uPA and E-cadherin expression in 98 primary tumors, and the results were correlated with several parameters related to metastasis.

RESULTS

Among 125 tumors, 42 (34%) were evaluated as having E-cadherin expression (E-cadherin-positive), and the other 83 (66%) were defined as having reduced E-cadherin expression (E-cadherin-negative). uPA immunoreactivity was observed in 82 tumors (66%). There were four subtypes of patterns of uPA and E-cadherin expression: 22 uPA-negative/E-cadherin-positive, 17 uPA-negative/E-cadherin-negative, 21 uPA-positive/E-cadherin-positive, and 65 uPA-positive/E-cadherin-negative, uPA overexpression and reduced E-cadherin expression were associated with lymph node metastasis, vessel invasion, serosal involvement, and poor prognosis. In addition, uPA-positive/E-cadherin-negative tumors were associated significantly with large tumors, positive serosal invasion, lymph node involvement, and poor prognosis. Patients with uPA-positive/E-cadherin-negative expression had the poorest prognoses, compared with the three other groups of patients uPA-positive/E-cadherin-negative tumors had a fourfold relative risk of death when compared with uPA-negative/E-cadherin-positive tumors. A Cox proportional hazard model projected lymph node status as the strongest of the prognostic variables followed by DNA ploidy patterns and uPA/E-cadherin tissue status.

CONCLUSIONS

These results indicate that immunohistochemical combination analysis of uPA and E-cadherin expression may be a powerful aid in evaluating metastatic potential or the prognosis of patients with gastric cancer.

Rapid ventricular induction of brain natriuretic peptide gene expression in experimental acute myocardial infarction

BACKGROUND

We have demonstrated that brain natriuretic peptide (BNP) is a cardiac hormone predominantly synthesized in and secreted from the ventricle. We have also reported that, compared with atrial natriuretic peptide (ANP), the plasma concentration of BNP is increased to a greater degree in patients with congestive heart failure and more rapidly in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

To investigate ventricular gene expression of BNP in AMI, we analyzed plasma and ventricular BNP concentrations along with ventricular BNP mRNA in rats with AMI produced by coronary artery ligation. The BNP concentration in the left ventricle increased about 2-fold as early as 12 hours postinfarction and 5-fold 1 day postinfarction compared with sham-operated rats, whereas left ventricular ANP concentration remained unchanged within 1 day. The tissue concentration of BNP increased in the noninfarcted region as well as in the infarcted region. The surviving myocytes in and around the necrotic tissues in the infarcted region were intensely stained with the anti-BNP antiserum, indicating augmented production in the remaining myocytes in the infarcts. The BNP concentration in the right ventricle also increased about 10-fold 12 hours postinfarction, whereas the ANP concentration remained unchanged within 12 hours. Northern blot analysis revealed that BNP mRNA expression was augmented 3-fold in the left ventricle as early as 4 hours postinfarction. In contrast, ANP mRNA expression was unchanged. Reflecting the rapid induction of ventricular BNP production, the plasma BNP concentration rose to about 100 pg/mL 12 hours postinfarction (sham-operated rats, < 70 pg/mL).

CONCLUSIONS

These results demonstrate the rapid induction of ventricular BNP gene expression in rats with AMI compared with ANP and suggest that BNP gene expression in the ventricle is regulated distinctively from ANP gene expression against acute ventricular overload. They also suggest that the BNP gene can be one of the acutely responsive cardiac genes for the ventricular overload and suggest a possible pathophysiological role of BNP distinct from ANP in AMI.

Carboxyl terminal of G protein beta subunit is required for association with gamma subunit

To investigate a complex formation of heterotrimeric G protein beta and gamma subunits, we constructed a deletion mutant which lacked the C-terminal WD40 repeating unit of beta 1 and cotransfected into HEK293 cells with gamma 2 which was tagged with FLAG-epitope. Co-immunoprecipitation assay indicated that the mutant beta 1 failed to associate with FLAG gamma 2. Furthermore, from the analysis of additional deletion mutants, the last 10 amino acids of C-terminal region of beta 1 were found to be necessary to associate with gamma 2. These results suggest that the C-terminal region, in addition to the N-terminal alpha-helical structure, of beta subunit may be involved in the beta gamma complex formation.

3D-spiral CT of multiple exostoses

We report pre- and post-operative three-dimensional (3D)-spiral CT images in a patient with multiple exostoses. Images of 3D-CT, which were performed using the integrated 3D software of the CT system, showed the exact shapes and locations of the individual tumors around the knee joint in comparison with the surgical findings and resected specimen. 3D-spiral CT images of multiple exostoses would be useful for the planning of surgical procedure.

Significance of detection of enterovirus RNA in myocardial tissues by reverse transcription-polymerase chain reaction

Enteroviruses are known to have association with human myocarditis and dilated cardiomyopathy (DCM). We screened biopsy specimens from patients with active myocarditis or DCM, and myocardial tissues from autopsy cases without cardiac diseases using polymerase chain reaction (PCR) gene amplification. Positive enteroviral signals were demonstrated from 4 of 5 patients with active myocarditis (80%), 7 of 42 patients with DCM(17%) and 3 of 27 autopsies (11%). Out of 7 PCR positive patients with DCM, 3 cases showed hypertrophy and disarray of cardiocytes, fibrosis in the interstitium, and a few inflammatory infiltrates. The remaining 4 cases with DCM and 3 PCR positive autopsy cases did riot exhibit histological findings compatible with those in myocarditis. Our results support the observations that enteroviruses are common aetiologic agents of myocarditis, and some cases of DCM. Our results also suggest the possibility that in some cases enteroviruses may persist in the myocardium without causing apparent pathological changes.