Lack of vasodilatory response in skeletal muscle blood vessels of aged spontaneously hypertensive rats

Regional hemodynamic responses to the vasodilators, hydralazine (1 mg/kg, i.v.) and verapamil (0.1 mg/kg/min, i.v.), were examined in conscious Wistar Kyoto rats (WKY) and spontaneously hypertensive rats (SHR), 15 and 50 weeks of age, using the radioactive microsphere method. The flow rates of heart and skeletal muscle in SHR were higher than those in WKY, and the flow rates of liver, kidney, intestines, and skin in SHR were lower than those in WKY. These differences between the regional blood flow in WKY and SHR were observed in both aged and young rats. The changes in organ blood flow induced by hydralazine and verapamil were similar for WKY and SHR in most organs. Both drugs increased the skeletal muscle blood flow in WKY and young SHR, but not in aged SHR, that is, the skeletal muscle blood vessels in aged SHR lost their vasodilatory response. These results suggest that, although a lack of vasodilatory responses in the skeletal muscle vasculature of aged SHR may be triggered by persistent hypertension, the vital organ vasculature maintains its normal vasodilating capacity.

Survival of F-reticulocytes in sickle cell disease

Fetal hemoglobin, Hb F, is known to be an important factor for clinical course of sickle cell disease, as it suppresses polymerization of sickle hemoglobin. To investigate the effect of Hb F on the survival of sickle reticulocytes (young red cells) in circulation, Hb F levels in individual reticulocytes and mature erythrocytes were quantified via fluorescence image cytometry. We first examined unfractionated SS cells from 3 patients with different Hb F levels, and found that Hb F levels in reticulocyte populations were always lower than those in erythrocyte populations. This suggests that subsets of reticulocytes with lower Hb F levels are removed during maturation while those with higher Hb F levels tend to survive to become erythrocytes. The distribution of Hb F in reticulocytes was different among these patients and seems to strongly affect the survival of F-reticulocytes. We also analyzed density-separated fractions, and found that Hb F levels in reticulocytes found in the densest fraction were lower than those in lighter fractions. This suggests that reticulocytes with lower Hb F levels are susceptible to quick dehydration within their maturation period (1-2 days) in circulation.

Lymphoepithelioma-like carcinoma of the lung: analysis of two cases for Epstein-Barr virus infection

Lymphoepithelioma-like carcinoma, which is an uncommon histological type of epithelial tumor, has been described as being closely associated with Epstein-Barr virus (EBV) infection in organs other than the lung. Recently, we experienced two surgically resected cases of pulmonary tumors mimicking lymphoepithelioma-like carcinoma. Both cases contained EBV DNA genomes as shown by polymerase chain reaction (PCR) using EBV DNA-specific primers, one positive for EBV DNA in virtually all cancer cells, and the other showing positive hybridization in a small number of cancer cells by in situ hybridization (ISH) using digoxigenin-labeled olignucletide probes for each of EBV DNA for EBV DNA. EBV-encoded RNA-1 (EBER-1) was typically detected in one case. These results are highly suggestive of EBV-associated tumors in one of the current cases, although in the other case, no such close association was determined. It seems that lymphoepithelioma-like pulmonary carcinoma, which seems extremely unusual, may be closely associated with EBV infection in tumorigenesis.

Estimation of fetal hemoglobin levels in individual red cells via fluorescence image cytometry

A method for estimating fetal hemoglobin (Hb F) levels in individual red blood cells was developed. Cell smears were prepared using a slide maker to ensure uniform thickness and were then stained with immunofluorescence. An antifading gel was applied to preserve a stable fluorescence. The total fluorescence intensities from the same number of red cells in different slide specimens correlated with their hemolysate Hb F levels, which were determined via column chromatography (R = 0.95). Hb F level in individual cells was estimated from fluorescence intensity and cell area, which were determined via image analysis techniques and the hemolysate Hb F level. Blood from a normal subject, a subject with hereditary persistence of fetal hemoglobin, and from sickle cell patients with varying Hb F levels was analyzed. Our analyses showed a wide distribution of Hb F among cells for the normal subject and a gaussian distribution with a peak at the hemolysate Hb F level for the subject with hereditary persistence of fetal hemoglobin. The Hb F distributions were unique to the patients with sickle cell disease. Because Hb F level in individual sickle cells is crucial to the inhibition of cell sickling, the unique hb F distribution may be important in determining the clinical course of this disease.

Evaluation of a new heparin bonding process in prolonged extracorporeal membrane oxygenation

A novel heparin bonding method has been developed for in situ surface modification using ozone oxidation, and evaluated in vitro and in vivo during prolonged extracorporeal membrane oxygenation (ECMO) experiments. The ECMO system consisted of a Capiox hollow fiber membrane oxygenator (MO; Terumo Corp., Tokyo, Japan) with an integral heat exchanger, a Capiox centrifugal pump (CP), and an extracorporeal circuit. The blood contacting surfaces of the system were completely modified using the heparin bonding process, and evaluated in a chronic sheep model for extended period of time, ranging from 96 to 168 hr, under minimal systemic heparinization. The heparin bonded surface was able to maintain high levels of heparin bioactivity, and showed improved blood compatibility in in vitro epifluorescent video microscopy experiments by suppressing platelet adhesion/activation and complement activation. For the ECMO experiments, extracorporeal blood flow was maintained at 3 L/min and the activated clotting time was maintained at 150 sec. There was no significant change in the gas transfer capability or mean pressure drop across the MO over experimental times of up to 168 hr. Platelet count and other coagulation parameters remained stable within the physiologic range throughout the experiment. There were no detectable thrombi in the CP, tubing, or connectors in the test circuit. Local thrombus formation was noted in a stagnant area of the MO, although this did not interfere with its function or lead to any significant embolization. Based on these results, the heparin bonded ECMO system appears to be a safe and effective device for prolonged extracorporeal circulation under minimal systemic heparinization.

Sickling in vitro at venous and arterial oxygen tensions of reticulocytes from patients with sickle cell disease

Sickling of reticulocytes and mature erythrocytes from patients with sickle cell disease was compared at venous and arterial oxygen tensions (PO2 = 30 and 90 mm Hg). Reticulocyte-rich fractions (d < 1.06) were partially deoxygenated in two ways after incubation at PO2 = 180 mm Hg: (1) PO2 of 30 mm Hg for 1 hour, and reoxygenation to 90 mm Hg for 2 hours and (2) PO2 of 90 mm Hg and kept for 2 hours. Percentages of sickled cells were always higher (3-5 times) in reticulocytes than in mature erythrocytes. Percentage of sickled reticulocytes measured at PO2 = 90 mm Hg after partial deoxygenation to PO2 = 30 mm Hg was 2 times higher than that obtained directly at PO2 = 90 mm Hg. In contrast, there was no difference in percentage of sickled cells in the mature erythrocyte population under the two experimental conditions. These results suggest that reticulocytes are more susceptible to sickling under venous oxygen tension and less likely than mature erythrocytes to resume discoidal shape even at arterial oxygen tension.

SOS induction in Escherichia coli by single-stranded DNA of mutant filamentous phage: monitoring by cleavage of LexA repressor

Infection of Escherichia coli in the presence of chloramphenicol with mutant filamentous phage that are defective in the initiation of minus-strand DNA synthesis induces the SOS response as monitored by cellular LexA levels. This observation demonstrates that single-stranded DNA serves as a primary signal for SOS induction in vivo.

A cell division inhibitor SulA of Escherichia coli directly interacts with FtsZ through GTP hydrolysis

E. coli SulA is an SOS-inducible protein that inhibits cell division. FtsZ is a protein that plays a central role in bacterial cell division. Using purified SulA protein that was fused to the maltose binding protein, we demonstrate in vitro that SulA interacts with FtsZ to form a stable complex. The reaction requires GTP and Mg ion. GDP and GTP gamma S cannot substitute for GTP, which suggests that hydrolysis of GTP is required for the reaction. The complex is formed in a molar ratio of approximately one to one of the two proteins. It is likely that the complex formation represents the in vivo mechanism by which SulA inhibits cell division.

[Artificial defect on myocardial SPECT image due to extra-cardiac MIBI accumulation]

If 99mTc-methoxy isobutylisonitrile (MIBI) myocardial scintigraphy was performed on the rest-stress protocol, MIBI accumulated in extra-cardiac area, gallbladder or liver, on rest image significantly. The purpose of this study was to evaluate whether extra-cardiac MIBI accumulation influences the quality of myocardial images. Rest-stress MIBI myocardial scintigraphy was performed in 90 patients. Fifteen patients showed defects on rest image in spite of normal findings on stress image. Before and after removing the area of extra-cardiac MIBI accumulation on projection images, SPECT was reconstructed in the 15 patients. Perfusion defect on rest image improved in 66% of patients (10/15) and 37% of total segments (33/89) by removing the area of extra-cardiac MIBI accumulation. Furthermore, it was 21% (4/19), 38% (11/29), 43% (16/37) and 50% (2/4) in anterior, septum, posterior and lateral segments respectively. Significant MIBI extra-cardiac accumulation, especially in the gallbladder, is one of the causes of artificial defects on rest image. Thus, reconstruction of SPECT after removing area of MIBI extra-cardiac accumulation will be an appropriate method to improve the quality of MIBI images.

Effects of a synthetic rat adrenomedullin on regional hemodynamics in rats

The effects of rat adrenomedullin, a novel vasorelaxant peptide, on systemic and regional hemodynamics were examined in conscious Sprague Dawley (SD) rats and spontaneously hypertensive rats (SHR). The intravenous infusion of adrenomedullin at rates of 1.67 and 5 micrograms/kg per min decreased the mean arterial pressure in a dose-dependent fashion in both types of rats. Adrenomedullin at a rate of 5 micrograms/kg per min increased the heart rate and cardiac output. As a result, the total peripheral resistance significantly decreased. With regards to the regional hemodynamics, adrenomedullin significantly increased the flow rates in the lungs, heart, spleen, kidneys, adrenal glands and small intestine of SHR. The flow rates in the brain and skin did not change and the flow rates in the skeletal muscle and testis were decreased. These regional hemodynamic changes were also observed in SD rats and there was no qualitative difference in the regional responses to adrenomedullin between SHR and SD rats. Thus, adrenomedullin predominantly increased the flow rates in organs in which adrenomedullin gene was highly expressed. It therefore seems that adrenomedullin may act as a local vasodilatory hormone rather than as a circulatory hormone.

[Evaluation of the chemotherapy of a transplantable bladder tumour strain (NM-B-1) by two anti-cancer drugs in combination with a pressor agent in nude mice]

The anti-cancer effects of either Cis-diammine (Glycolato) platinum II (CDGP-II), a novel platinum derivative, or ifosfamide (IFX) on bladder carcinoma strain NM-B-1 inoculated in nude mice were examined. These chemotherapeutic agents were compared with each other in terms of their inhibitory effect on tumor growth, their histology, and the concentration of each agent in the blood, tumor tissue, liver and kidneys. (1) The tumor growth was inhibited by CDGP-II in all three different dosage groups (p < 0.05), but not by IFX (p > 0.05). These results were also confirmed by histological examination. (2) The amount of CDGP-II (30 mg/kg) in the tumor tissue increased in a time-dependent manner, while in the blood plasma and kidney tissue, it decreased. Total value (TV) and active metabolite (AML) of IFX (500 mg/kg) were examined. TV in the tumor tissue decreased in a time-dependent manner. AML could not be detected. There was no change of AML in the blood plasma, liver, and kidneys. (3) Transmigration of single loading of CDGP-II or IFX with Angiotensin II (AT-II) from blood into the tissue was examined. CDGP-II in the blood plasma, tumor, liver and kidneys increased in a time-dependent manner. After single administration of IFX, TV decreased in the blood plasma, tumor, liver and kidneys, while AML increased in the blood and kidneys (p < 0.01). (4) The results suggest that CDGP-II may have an anti-tumor effect of NM-B-1. However, the effect can not be enhanced under the influence of a pressor chemotherapeutic agent.(ABSTRACT TRUNCATED AT 250 WORDS)

Deoxyspergualin is a new radioprotector in mice

A novel immunosuppressant, deoxyspergualin, given at doses of 2.5 to 20 mg/kg/day on days -3, -2 and -1 before X irradiation protected BALB/c mice from the lethal effects of radiation in a dose-dependent manner. The dose of radiation that killed 50% of the mice within 30 days was 5.63 Gy for mice receiving radiation alone, but was 7.13 Gy in the mice given deoxyspergualin at 20 mg/kg. Prior administration of deoxyspergualin ameliorated leukopenia and thrombocytopenia induced by sublethal irradiation, and significantly increased the number of femoral spleen colony-forming units (CFU-S) that survived irradiation. Deoxyspergualin also reduced the proportion of CFU-S in S phase, as determined by in vitro sensitivity to hydroxyurea. These findings suggest that deoxyspergualin may be effective in the prevention of hematopoietic injury caused by radiotherapy.

Development and usefulness of the gelatin-particle-agglutination test for titration of antibodies against diphtheria, pertussis and tetanus toxins

The gelatin-particle-agglutination (PA) test for titrating antibodies against diphtheria, pertussis and tetanus toxins was developed and used for assaying 65 sera from healthy children to assess the antitoxin acquisition in relation to the administration of adsorbed diphtheria-purified pertussis-tetanus (DPT) combined vaccine. The antitoxin titers obtained by the PA test and the conventional methods were correlated well; the correlation coefficient of the diphtheria antitoxin titers between the PA test and the cell culture method was 0.908, that of the tetanus antitoxin titers between the PA test and the passive hemagglutination test 0.968, and that of anti-pertussis toxin titers between the PA test and polystyrene-ball ELISA 0.885. The PA test was shown to be useful in both developed and developing countries, since it is simple to perform, sensitive and specific, and the three antitoxins can be titrated by the same procedure.

Mandibular reconstruction using the double barrel fibular graft

Five patients underwent mandibular reconstruction using the double barrel fibular graft from 1989 to 1994. Bony defects ranged from 7 to 14 cm. In three patients, two skin flaps were taken with the fibular graft for composite reconstruction. In order to overcome the main disadvantage of the fibular graft, i.e., small circumference of the bone, a harvested fibula was osteotomized into several portions, folded into two parallel lengths, and fixed along the inferior border of the mandible and the alveolar ridge. The double barrel fibular graft provided more than 4-cm alveolar height without damaging bone viability. In Orientals, a fibula is approximately 1.5 cm thick, and using a single fibular strut for mandibular reconstruction may result in subsequent difficulty in wearing conventional dentures or osseointegrated implants. All patients acquired good mandibular contour and enough thickness of the alveolar ridge, and could wear a conventional denture and eat a solid diet. This procedure seems to be superior to the iliac bone graft for major mandibular reconstruction because of its length, the possibility of three-dimensional composite reconstruction, increased bone thickness, and minimal donor-site morbidity.

Epstein-Barr virus in the proliferative diseases of squamous epithelium in the oral cavity

The presence of Epstein-Barr virus was analyzed in 79 cases of oral epithelial proliferative diseases by polymerase chain reaction, in situ hybridization for Epstein-Barr virus-deoxyribonucleic acid and Epstein-Barr virus-encoded small messenger ribonucleic acid and immunohistochemistry for Epstein-Barr virus latent membrane protein. These lesions were histologically categorized as invasive squamous cell carcinoma (n = 36), carcinoma in situ (n = 10), verrucous carcinoma (n = 4), leukoplakia (n = 19), and papilloma (n = 10). Epstein-Barr virus genomes were detected in 19 squamous cell carcinoma (52.8%), four carcinoma in situ (40%), and one leukoplakia (5.3%); none of the verrucous carcinoma or papilloma cases were positive with polymerase chain reaction. By deoxyribonucleic acid in situ hybridization, positive signals were observed in the nuclei of cancer cells in 10 cases, in infiltrating lymphocytes in three, and both in one case. In patients with carcinoma in situ, only a single case was positive. In one case of leukoplakia positive signals were found in upper and middle layer squamous cells. The results by Epstein-Barr virus-encoded small messenger ribonucleic acid in situ hybridization revealed the same distribution as that by deoxyribonucleic acid in situ hybridization. Latent membrane protein was expressed only in the epithelial cells of leukoplakia but not in cases with squamous cell carcinoma and carcinoma in situ. These findings suggest that Epstein-Barr virus infection of oral squamous epithelium may be carcinogenic; alternatively, the virus may merely exist in epithelial cells of squamous cell carcinoma, carcinoma in situ, and leukoplakia as a passenger.

Quantitative analysis of the degree of irreversible deformation of F cells and non-F cells and its relationship to cell density in sickle cell disease

To study the effect of fetal hemoglobin (Hb F) on the formation of dense and irreversibly deformed cells in patients with sickle cell disease (SCD), we investigated the distribution of Hb F and Hb F cells (FC, cells having HbF) and the difference in the degree of irreversible deformation between FC and non-Hb F cells (NFC) in relation to their cell density. We used immunofluorescence to define FC and image analysis to quantify the degree of deformation. Blood samples from 16 patients with Hb F levels ranging from 4 to 24% were separated into less dense [top (T), d < 1.11 g/mL] and dense [bottom (B), d > or = 1.11 g/mL] fractions. We found higher percentages of Hb F and FC in top fractions, suggesting that FC are hydrated more than NFC. Quantitative shape analysis demonstrated that the irreversible deformation of FC in the top fraction [FC(T)] was not significantly different from that of NFC in the fraction [NFC(T)] (p = 0.163), but rather that the irreversible deformation of FC in the bottom fraction [FC(B)] was much milder than for NFC(B) (p < 0.001). The order of the degree of irreversible deformation was NFC(B) > FC(B) > NFC(T) = FC(T). These results clearly demonstrated that FC are less susceptible to both irreversible deformation and dehydration than NFC, suggesting that in circulation, the sickling process plays a major role in cell dehydration. Additionally, we found that the ratio of NFC(B) to FC(B) decreased as a patient's Hb F increased (r = 0.84) and that NFC(B) = FC(B) when Hb F was about 20%.

The margin of safety in the use of a straight path centrifugal blood pump

A new centrifugal blood pump with a rotor that arranges 6 straight paths radially was developed for open heart surgery and temporary circulatory support. We describe comparative studies of the margin of safety in the practical use of the new pump. This pump was evaluated for temperature increase, cavitation, and pressure sensitivity. Two commercially available centrifugal pumps, the Biomedicus cone type and the Sarns 3M impeller type, were used as control pumps. The temperature increase in the new pump was four times slower than in the impeller pump when the outlet and the inlet of the pump was clamped. No sign of cavitation was observed when 0.1 ml air was introduced to the pump inlet under a negative pressure of 200 mm Hg in fresh bovine blood. As for pressure sensitivity of centrifugal pumps in practical applications, circuit resistance was a more essential factor than flow-pressure curves of the pump.

Epstein-Barr virus in patients with polymorphic reticulosis (lethal midline granuloma) from China and Japan

BACKGROUND

Polymorphic reticulosis is one of several diseases constituting lethal midline granuloma (LMG). Previous immunohistochemical studies suggested a T-cell nature of proliferating cells; the term nasal T-cell lymphoma (NTL-LMG) has since been used widely. The authors' previous study in Asian countries showed the clustering of Mongolian patients with NTL-LMG, but the frequency varied with geographic area; it was much higher in Korea and southwest Japan (Okinawa) than in Shanghai and Honshu, Japan. Recently an etiologic role of Epstein-Barr virus (EBV) for the development of NTL-LMG has been postulated.

METHODS

In this study, the presence of EBV and human T-cell lymphocytic leukemia virus type 1 (HTLV-1) genomes were examined in NTL-LMG patients from Southwest Japan (Okinawa, 10 patients), another Japanese district (Honshu, 21 patients), and Shanghai, China (5 patients). All of the tissues from different geographic sites were analyzed at one central location.

RESULTS

Immunohistochemistry showed that proliferating large cells were positive for CD43 and/or CD45RO, identical with reported NTL-LMG cases. Polymerase chain reaction (PCR) revealed the presence of EBV genome in the NTL-LMG lesions, but the frequency varied according to the geographic area: 67% in Okinawa, 33% in Honshu, and 100% in Shanghai. In situ hybridization provided positive signals in the nuclei of proliferating cells. Expression of latent membrane protein in the proliferating cells of cases positive for EBV by PCR and in situ hybridization was confirmed.

CONCLUSIONS

The results suggest that the EBV may play a role in the development of NTL-LMG. However, the variation of frequency of EBV genome in different geographic locations suggests that EBV infection may not be an indispensable condition for the disease.

A general and fast method for mapping mutations on the Escherichia coli chromosome

Images

Epstein-Barr virus in patients with polymorphic reticulosis (lethal midline granuloma) from China and Japan

BACKGROUND

Polymorphic reticulosis is one of several diseases constituting lethal midline granuloma (LMG). Previous immunohistochemical studies suggested a T-cell nature of proliferating cells; the term nasal T-cell lymphoma (NTL-LMG) has since been used widely. The authors' previous study in Asian countries showed the clustering of Mongolian patients with NTL-LMG, but the frequency varied with geographic area; it was much higher in Korea and southwest Japan (Okinawa) than in Shanghai and Honshu, Japan. Recently an etiologic role of Epstein-Barr virus (EBV) for the development of NTL-LMG has been postulated.

METHODS

In this study, the presence of EBV and human T-cell lymphocytic leukemia virus type 1 (HTLV-1) genomes were examined in NTL-LMG patients from Southwest Japan (Okinawa, 10 patients), another Japanese district (Honshu, 21 patients), and Shanghai, China (5 patients). All of the tissues from different geographic sites were analyzed at one central location.

RESULTS

Immunohistochemistry showed that proliferating large cells were positive for CD43 and/or CD45RO, identical with reported NTL-LMG cases. Polymerase chain reaction (PCR) revealed the presence of EBV genome in the NTL-LMG lesions, but the frequency varied according to the geographic area: 67% in Okinawa, 33% in Honshu, and 100% in Shanghai. In situ hybridization provided positive signals in the nuclei of proliferating cells. Expression of latent membrane protein in the proliferating cells of cases positive for EBV by PCR and in situ hybridization was confirmed.

CONCLUSIONS

The results suggest that the EBV may play a role in the development of NTL-LMG. However, the variation of frequency of EBV genome in different geographic locations suggests that EBV infection may not be an indispensable condition for the disease.

Carcinoma of stomach and breast with lymphoid stroma: localisation of Epstein-Barr virus

AIMS

To determine the presence of Epstein-Barr virus (EBV) genome in six patients (three with gastric and three with breast carcinoma) with severe small lymphoid cell infiltration.

METHODS

The polymerase chain reaction and in situ hybridisation were used to detect EBV genome. The number and distribution of T and B lymphocytes were evaluated by immunohistochemistry.

RESULTS

Histologically all of the patients had poorly differentiated tumours. Immunohistochemistry showed that T cells predominated in three cases, B cell in two, and almost equal numbers in one case. PCR showed that the EBV genome was present in two cases each of gastric and breast carcinoma. In situ hybridisation for EBV genome provided positive signals only in the small lymphoid cells in one gastric and two breast carcinomas giving a positive reaction for EBV genome by PCR. The gastric and breast cancer cells did not give positive signals.

CONCLUSIONS

Severe lymphoid cell infiltration in gastric and breast carcinoma does not necessarily indicate that these tumours are associated with EBV. Larger numbers of cases will need to be studied to confirm this.

[Detection of viability by percent thallium uptake with conventional thallium scintigraphy]

Thallium myocardial scintigraphy (TMS) is used for diagnosis of viability in infarcted myocardium before coronary revascularization. Underestimation of viability by TMS has been reported by many investigators. To evaluate viability precisely, thallium re-injection method or 24 hour delayed imaging is performed. However these techniques are not convenient and are difficult to perform in clinical practice. Percent Tl-uptake method was developed for predicting myocardial viability. To evaluate usefulness of this method, TMS was performed before and after PTCA in 23 patients with myocardial infarction. Left ventricle was divided into 3 layers, then each layer was divided into 4 segments (12 segments in total). Forth three segments showed recovery of perfusion on TMS after PTCA. Viability in infarcted myocardium is predicted by 1) redistribution (RD), 2) %Tl-uptake > or = 45% on the image immediately after exercise (TE), and 3) %Tl-uptake > or = 45% on delayed image (TD). Sensitivity was RD: 60%, TE: 90% and TD: 95% (p < 0.001 vs. RD). Specificity was RD: 74%, TE: 68%, and TD: 60% (NS). Predictive accuracy (PA) was RD: 69%, TE: 77%, TD: 73% (NS). Compared with RD, %Tl-uptake, either TE or TD, increased sensitivity with slightly improved PA, but decreased specificity slightly. Therefore %Tl-uptake would be a sensitive and useful predictor to find patients who are most likely to benefit from re-vascularization.

Multiple DNA conformational changes induced by an initiator protein precede the nicking reaction in a rolling circle replication origin

The core origin for plus strand DNA replication of filamentous bacteriophage f1 binds the initiator protein (gpII), which subsequently introduces a specific nick in the plus strand. The core origin consists of a nicking region and a binding region. The binding of gpII occurs in two steps, forming a binding intermediate (complex I) and a functional complex for nicking (complex II). Results of gel retardation experiments using circularly permuted DNA fragments and direct visualization by electron microscopy show that gpII induces successive bends within the binding region upon formation of the complexes. We show that gpII binding induces duplex melting in the nicking region using KMnO4 modification of unpaired thymidine residues as a probe for melting. Origin binding occurred in the absence of superhelicity of DNA and Mg2+, whereas duplex melting required superhelical DNA, but not Mg2+. Deletion analyses indicated that hypothetical formation of a cruciform around the nicking site is not necessary for either melting or nicking. A mutation in gpII resulted in stimulation of duplex melting and nicking without showing obvious effects on bending. This suggests that the mechanism of melting involves local interaction between gpII and the nicking region. Furthermore, using synthetic oligonucleotide substrates, we show that the nicking reaction takes place efficiently when the nicking region is single-stranded and the binding region is double-stranded. These results indicate that the nicking reaction is preceded by an ordered series of protein-induced DNA-conformational changes: successive bending of the origin upon gpII binding, followed by duplex melting that requires negative superhelicity.

[Clinical treatment of urinary tract stones with Alexandrite laser]

Clinical treatment of urolithiasis with Alexandrite-laser which is a solid pulse laser system developed in Switzerland is reported. Two cases of renal stones, 3 cases of vesical stones, and 35 renal units in 34 cases of ureteral stones were treated. The approach to the aimed stone was, percutaneous to the renal stones, and transurethral to the vesical and ureteral stones. The clinical success rate was 92.5% (37/40), when we defined success as the endoscopically observed fragmentation. The uric acid stone in the bladder was not disintegrated even when the plasma occurred, but the ureteral uric acid stone was easily fragmented. The difference was thought to be attributed to the condition of the surface. The Alexandrite-laser system generates a 750 nm wavelength, and this wavelength is neither absorbed in water nor hemoglobin, so is thought to be harmless to the tissue. Actually, if misirradiation to the ureteral mucosa during lithotripsy was done, neither plasma formation nor perforation occurred. In conclusion, the Alexandrite-laser is thought to be safe and effective equipment for the treatment of urolithiasis.

A hydrophilic tetrahydro-beta-carboline in human urine

A substance that exhibited a tryptophan-like fluorescence peak at 354 nm on excitation at 295 nm at neutral pH was isolated from human urine. This compound was determined by visible-light absorption spectroscopy, fluorescence spectroscopy, 1H and 13C NMR spectroscopies, and FAB-MS to be 1-(1',2',3',4',5'-pentahydroxypentyl)-1,2,3,4-tetrahydro-2-carboli ne-3- carboxylic acid. This compound, named tetrahydropentoxyline, is a new type of hydrophilic tetrahydro-beta-carboline, and its elution position was between those of 4-pyridoxic acid and kynurenic acid on C18 reversed-phase HPLC. The amount of tetrahydropentoxyline excreted in the urine of normal subjects [n = 21; age, 45 (SD 20) years] was about 5.2 (SD 1.0) mg per day.

Urinary bone resorption markers in patients with metabolic bone disorders

Recently, urinary pyridinoline and deoxypyridinoline have been commonly employed as bone resorption markers. We studied these markers in 17 patients with hyperthyroidism, 15 undergoing long-term anticonvulsant drug therapy, and 28 with postmenopausal osteoporosis. Both markers had significantly higher levels than those in age-matched control groups. Values of urinary pyridinoline and deoxypyridinoline correlated well with urinary hydroxyproline levels in patients with hyperthyroidism (r = 0.856, p < 0.001 for pyridinoline and hydroxyproline; r = 0.919, p < 0.001 for deoxypyridinoline and hydroxyproline); however, poor correlations were observed, especially between urinary deoxypyridinoline and urinary hydroxyproline (r = 0.357, NS) in patients with postmenopausal osteoporosis. To compare the discriminatory ability of urinary pyridinoline and deoxypyridinoline, receiver operating characteristic (ROC) curves were generated for each of these patient groups using data from age-matched healthy females as the control group. The areas under the curves for both markers were 100.0% in hyperthyroidism. The areas under the curves for pyridinoline in patients undergoing long-term anticonvulsant drug therapy (mean +/- SE; 98.1 +/- 2.8%) and postmenopausal osteoporosis (77.9 +/- 5.7%) were significantly higher than those for deoxypyridinoline in anticonvulsant drug therapy (92.4 +/- 3.3%) and in osteoporosis (64.9 +/- 4.3%). Using data from premenopausal healthy females as the control group, areas under ROC curves for urinary pyridinoline (100.0%) and deoxypyridinoline (94.8 +/- 5.9%) were significantly higher than those for urinary hydroxyproline (73.8 +/- 9.4%) in patients undergoing long-term anticonvulsant drug therapy. In patients with postmenopausal osteoporosis, those for urinary pyridinoline (97.0 +/- 2.8%) were also significantly higher than those for urinary hydroxyproline (74.0 +/- 6.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

The mechanism of chlorpromazine-induced red blood cell swelling

1. Chlorpromazine (CPZ)-induced red blood cell (RBC) swelling was investigated by determination of electrolyte, mean cell volume (MCV) and water content changes in CPZ-treated cells. 2. CPZ-induced RBC swelling is dose-, hematocrit- and pH-dependent, and is associated with a net increase in RBC monovalent cation and Cl- contents. 3. The partition coefficient (Kp) for the CPZ-RBC membrane interaction is pH dependent (Kp = 2500 at pH 7.8; Kp = 840 at pH 6.8). 4. Despite the pH dependence of Kp values an equal number of CPZ molecules is required to induce a 12% increase in MCV at pH 7.8 and 6.8.

The occurrence of monocytoid B-lymphocytes in the spleen in gastric cancer

Occurrence of monocytoid B-lymphocytes (MBL) in spleens of 34 patients with gastric cancer was examined. Histologic findings of gastric cancer including classification, depth of invasion, and stage of disease were defined based on the General Rules for the Gastric Cancer Study (Japan). MBL were defined morphologically as having abundant pale cytoplasm with distinct cell borders and small nucleus often with reniform shape. Immunohistochemically, these cells were B-cell in nature, i.e., CD15-, CD43-, CD45RA+, CD45Ro-, CD68-, CD74+, CDw75+, Mx-PanB(L26)+, MBI+, EMA-, PG-MI-. Clusters of MBL were found in 14 of 34 (41%) patients: they were found to be directly adjoining to the periarterial sheath or apart from the white pulp. In the cases without MBL, zonation of mantle zone and marginal zone was apparent with distinct secondary follicles in 72% of cases. Meanwhile, in spleens with MBL, the mantle zone showed atrophy in a half of cases, resulting in indistinct zonation of the mantle zone and marginal zone. Secondary follicles were distinct in less than 30% of cases. Correlation of the occurrence of MBL, evaluated by Spearman's correlation coefficient, revealed that the age was the most important factor (R = -0.4852, P = 0.00364): the median age of patients with and without MBL was 75.7 and 61.7 yr, respectively. The MBL were increased in gastric cancer as compared with other cancers (P < 0.03) and with noncancer spleens (P < 0.1). The age of gastric cancer patients with MBL was older than those in other cancers and noncancer patients. Therefore occurrence of MBL in spleen might be a function of aging.

Dose-dependent red blood cell volume increase induced by bepridil

1. Bepiridil, (beta-[(2-methylpropoxy)methyl]-N-phenyl-N-(phenyl-methyl)-1-py rro lidine-ethanamine), a calcium channel blocker, inhibits sickling of red blood cells (RBC) from patients with sickle cell disease (SCD) at micromolar concentrations in vitro. 2. Bepridil induces dose-dependent osmotic swelling of RBC and a concomitant decrease in mean corpuscular hemoglobin concentration (MCHC). 3. Modest decreases in MCHC greatly lengthen the delay time for polymerization of deoxygenated sickle hemoglobin (Hb S) and inhibit RBC sickling. 4. Equilibrium dialysis studies of bepridil and purified hemoglobin showed a low binding affinity (Kb = 10(3)/M). 5. The partition coefficient (Kp) determined for the interaction of RBC and bepridil was 1-3 x 10(3), which is similar to the Kp determined for other amphipathic molecules, such as chlorpromazine.

Quantification of the cross-link pentosidine in serum from normal and uremic subjects

Pentosidine is a fluorescent cross-link compound that accumulates in human tissues from uremic and diabetic patients. Using SP-Sephadex C-25 pretreatment before reversed-phase HPLC, we developed a method for quantifying pentosidine in the acid hydrolysate of serum. We examined concentrations of pentosidine in serum from 98 patients with end-stage renal disease requiring hemodialysis and from 33 normal control subjects. The mean (+/- SD) concentration of pentosidine was significantly greater in serum from uremic patients than that from control subjects (1267 +/- 695 nmol/L vs 77 +/- 40 nmol/L, P = 0.0001). There was a significant correlation between serum pentosidine concentrations and age in control subjects (r = 0.453, P &lt; 0.01), but not in uremic patients. Serum pentosidine significantly increased with the duration of hemodialysis treatment (r = 0.272, P &lt; 0.05). The greater pentosidine concentrations in uremic patients may be caused by the increased synthesis of pentosidine (perhaps because of the retention of pentosidine precursors), by the retention of pentosidine molecule itself in end-stage renal failure, or both.

Quantification of the cross-link pentosidine in serum from normal and uremic subjects

Pentosidine is a fluorescent cross-link compound that accumulates in human tissues from uremic and diabetic patients. Using SP-Sephadex C-25 pretreatment before reversed-phase HPLC, we developed a method for quantifying pentosidine in the acid hydrolysate of serum. We examined concentrations of pentosidine in serum from 98 patients with end-stage renal disease requiring hemodialysis and from 33 normal control subjects. The mean (+/- SD) concentration of pentosidine was significantly greater in serum from uremic patients than that from control subjects (1267 +/- 695 nmol/L vs 77 +/- 40 nmol/L, P = 0.0001). There was a significant correlation between serum pentosidine concentrations and age in control subjects (r = 0.453, P < 0.01), but not in uremic patients. Serum pentosidine significantly increased with the duration of hemodialysis treatment (r = 0.272, P < 0.05). The greater pentosidine concentrations in uremic patients may be caused by the increased synthesis of pentosidine (perhaps because of the retention of pentosidine precursors), by the retention of pentosidine molecule itself in end-stage renal failure, or both.

Image analysis studies of the degree of irreversible deformation of sickle cells in relation to cell density and Hb F level

We analyzed, quantitatively by image analysis, the degree of irreversible deformation of red cells (SS cells) from patients with homozygous sickle cell disease, and studied the relationships among the degree of irreversible cell deformation, cell density, and Hb F level. SS cells from 25 patients (aged 1-36 years) whose Hb F levels ranged from 2.5% to 40.0%, were fully oxygenated and then were separated into four fractions by density centrifugation. Every fraction was studied for morphology and Hb F content. We found that the irreversible deformation of SS cells from the circulation occurred mainly by elongation and that the degree of elongation was extremely variable. We also found that in the cells of patients with Hb F levels < 20% the degree of irreversible elongation increases as cell density increases, suggesting that dehydration occurs concomitantly with irreversible elongation. Statistical analysis (Student t test) indicated that there were significant differences (P = 0.008 or < 0.001) in the degree of elongation among density-fractionated SS cells from patients with Hb F < 20%, although there was no significant difference (P > 0.1) among those from patients with Hb F > or = 20%. We also found that cell density increased as Hb F level of the density fraction decreased in all patients with Hb F < 20% but not always in those with Hb F > or = 20%. This suggests that cells with lower Hb F levels are selectively susceptible to dehydration. Furthermore, we found that the mean degree of irreversible elongation decreases linearly with increasing levels of Hb F and reaches the normal range at 21-24%. Since the degree of irreversible deformation of SS cells quantified by image analysis is directly related to cell density, and inversely to Hb F levels, mechanical stress or membrane damage caused by Hb S polymerization may be an important factor in the formation of dense cells in vivo.

[Clinical application of transrectal ultrasonic therapy to nonbacterial prostatitis and prostatodynia cases which were resistant to conventional drug therapy]

A total of 25 patients with nonbacterial prostatitis and prostatodynia which were resistant to conventional drug therapy underwent 5 minutes course of transrectal ultrasonic therapy in association with application of 1% hydrocortisone acetate cream to the anterior rectal wall for consecutive 8 days. The efficacy of the treatment was evaluated only by comparison of symptom scores for subjective symptoms obtained before and after treatment. Excellent results, which were defined as more than 70% reduction of symptom scores after treatment, were obtained in 5 (27.8%) among 18 evaluable cases in which symptom scores before treatment were more than 4, good (40-69% reduction of scores) in 4 (22.2%), fair (10-39% reduction of scores) in 4 (22.2%) and poor (less than 10% reduction of scores) in 5 (27.8%). Because of good clinical efficacy and the absence of complication, transrectal ultrasonic therapy combined with hydrocortisone acetate cream application was thought to be useful for the treatment of nonbacterial prostatitis and prostatodynia cases which responded poorly to the conventional therapy.

Age-related changes of urinary pyridinoline and deoxypyridinoline in Japanese subjects

Urinary pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) are commonly used as bone resorption markers because they are more sensitive to bone resorption than is urinary hydroxyproline. Age-related changes of urinary Pyr and D-Pyr were studied in 337 healthy females, aged 1 to 93 y, and 113 healthy males, aged 3 to 75 y. Levels of urinary Pyr and D-Pyr follow a characteristic pattern as one ages, with very high values during childhood decreasing to low baseline levels in adulthood between 20 and 49 y. Both values in the 0-19 y age group were significantly higher than those in the other age groups for both sexes. These values increased moderately but significantly in females in the 50-59 y age group compared to those in the 40-49 y age group (Pyr: 26.4 +/- 7.6 vs. 19.3 +/- 6.2 nmol/mmol creatinine, p < 0.05; D-Pyr: 7.7 +/- 2.4 vs. 5.6 +/- 2.2 nmol/mmol creatinine, p < 0.05). In contrast, these values stayed at low levels in the 50-59 y age group in males. The values of urinary Pyr and D-Pyr were significantly higher in females than in males in the 50-59 y age group (females vs. males--Pyr: 26.4 +/- 7.6 vs. 17.0 +/- 3.9 nmol/mmol creatinine, p < 0.05; D-Pyr: 7.7 +/- 2.4 vs. 4.7 +/- 1.2 nmol/mmol creatinine, p < 0.05). In our cross-sectional study, the values of urinary Pyr and D-Pyr increased in childhood (0-19 y), and in the early postmenopausal period (50-59 y). These 2 urinary markers reflect the age-related changes of bone resorption.

Malignant lymphoma of the uterus. Report of seven cases with immunohistochemical study

BACKGROUND

Uterine lymphoma is a rare disease; therefore, information regarding histologic type, immunophenotype of tumor cells, and etiologic factors are limited.

METHODS

Seven patients with uterine lymphoma, three from the corpus and four from the cervix, were collected by a nationwide study in Japan. Selection of cases was preferentially made from the "Annual of Pathologic Autopsy Cases in Japan."

RESULTS

All cases with cervical lymphoma presented with vaginal bleeding. Abdominal pain or backache was observed in patients with corpus lymphoma. The age ranges of patients with corpus and cervical lymphomas were 46-78 years of age (mean, 63 years) and 30-71 years of age (mean, 53 years), respectively. Information about clinical staging was available for six patients; two patients with Stage I, three patients with Stage II, and one patient with Stage III. A definite diagnosis of uterine lymphoma was made by biopsy in all cases. Total hysterectomy, with or without bilateral salpingo-oophorectomy, was carried out in three patients, and tumor resection was carried out in one patient. Adjuvant therapy was given in six cases. Follow-up showed that five patients died due to tumor within 1 year of treatment. Histologically, all cases were non-Hodgkin lymphoma showing a diffuse pattern of proliferation. All but one were diffuse large cell type. Immunohistochemistry revealed the tumor cells in all cases were of B-cell nature. Expression of HLA-DR antigen was evaluable in four cases, of these three showed an increased expression on the vascular endothelium.

CONCLUSIONS

Uterine lymphoma comprises exclusively B-cell type.

Malignant lymphoma of bladder. Report of three cases and review of the literature

BACKGROUND

The significance of long-standing cystitis has been postulated as a causal factor in malignant lymphoma of bladder.

METHODS

The authors reviewed 3 cases of primary malignant lymphoma of the urinary bladder and an additional 27 cases described in the literature (25 from Western countries and 2 from Japan). Clinical and pathologic findings in the total 30 cases are summarized.

RESULTS

The majority of patients presented with gross hematuria and were between 20 and 85 years of age (median age, 64 years). Marked female preponderance was found (male to female ratio, 1:6.5). Six patients (20%), all of whom were women, out of 30 had a history of chronic cystitis. Macroscopic findings showed a solitary mass (22 cases), multiple masses (6 cases), or a diffuse lesion without nodule formation (2 cases). The vast majority of bladder lymphoma were non-Hodgkin lymphoma (NHL) of B-cell type; among them, 14% were follicular lymphomas. Follow-up indicated that NHL of bladder had a favorable prognosis.

CONCLUSIONS

Malignant lymphoma of bladder is characterized by a preponderance in women, who are occasionally affected by chronic cystitis.

Osmoregulation of the fatty acid receptor gene fadL in Escherichia coli

The fadL gene of Escherichia coli codes for an outer membrane protein that is involved in the uptake of long-chain fatty acids. Uptake is regulated by environmental osmolarity, and decreases when the cells are grown under conditions of high osmolarity. A temperature-sensitive mutant that requires fatty acid for growth at 42 degrees C was unable to grow at the high temperature even in the presence of fatty acid if the medium contained 10% sucrose. Promoter activity of the fadL gene in vivo was repressed by high osmolarity in a FadR repressor null mutant. Furthermore, in vitro transcription of the fadL gene was strongly repressed by the addition of OmpR and EnvZ proteins. The results of gel retardation and DNase I protection experiments indicated that OmpR, after incubation with the protein kinase EnvZ, specifically binds to at least four sites around the fadL promoter, two upstream and two downstream from the transcriptional start site. These results suggest that transcription of the fadL gene is osmotically regulated by the OmpR-EnvZ two-component system.

Primary lymphoma of the brain developing in a boy after a 5-year history of encephalitis: polymerase chain reaction and in situ hybridization analyses for Epstein-Barr virus

A 7-year-old boy presented with headache, vomiting, fever, epileptic seizure, and a left hemiparesis. Computed tomography revealed low-density areas in the left frontal lobe and right occipital lobe. Incisional biopsy of the right occipital lesion showed a diffuse and laminar destruction accompanied by microglial reaction in the cortex. An encephalitis of unknown etiology was suspected without data on viral titers in the serum and cerebrospinal fluid. Two months later right hemiparesis and ataxia appeared that were alleviated by prednisolone. Thereafter, similar symptoms repeatedly appeared, but disappeared after treatment with prednisolone. Approximately 5 years later, hemiparesis recurred: computed tomography revealed an 8 x 5 cm mass in the right lobe. A brain biopsy revealed non-Hodgkin's lymphoma of diffuse large, predominantly non-cleaved cell type of B-cell nature. The patient died 1 week after the surgery. The first biopsy specimen (taken at 7 years of age) did not contain Epstein-Barr virus genomes even when examined by polymerase chain reaction. The polymerase chain reaction and in situ hybridization techniques on the second biopsy specimens (taken at 12 years of age) revealed the Epstein-Barr virus sequences in the nuclei of diffuse large cell lymphoma. These findings suggested that the Epstein-Barr virus infection occurring between the first and second biopsies played an etiologic role in the pathogenesis of the brain lymphoma.

The Maillard protein cross-link pentosidine in urine from diabetic patients

The Maillard protein cross-link pentosidine is a fluorescent condensation product of lysine, arginine and ribose. It accumulates in human tissues with age, and the accumulation process is accelerated in the tissues of diabetic patients. Using SP-Sephadex C-25 in the pretreatment for HPLC, we examined levels of pentosidine in urine without hydrolysis (free form) and levels of pentosidine in urine after hydrolysis (total forms), from 23 diabetic patients and 21 control subjects. The mean percentages of the values of free form per total forms (+/- SD) were 89 +/- 15% in diabetic patients, 88 +/- 16% in control subjects and 89 +/- 15% in total populations of diabetic patients and control subjects. There was a significant correlation between the values of free form and total forms in diabetic patients (r = 0.983, p = 0.0001), in control subjects (r = 0.820, p < 0.02) and in total populations of diabetic patients and control subjects (r = 0.951, p = 0.0001). The mean level of pentosidine per mol creatinine (+/- SD) was significantly elevated in urine from diabetic patients as compared to the level in control subjects (8.8 +/- 4.3 mumol/mol creatinine vs 4.2 +/- 1.4 mumol/mol creatinine, p = 0.0001 in free form; 10.1 +/- 5.3 mumol/mol creatinine vs 4.7 +/- 1.4 mumol/mol creatinine, p = 0.0001 in total forms). These results demonstrate that urinary pentosidine, especially in free form, could be a useful marker for the assessment of diabetes and diabetic complications.

Comparative studies of phenothiazine derivatives for their effects on swelling of normal and sickle erythrocytes

1. Three phenothiazines with similar structure; chlorpromazine (CPZ), triflupromazine (TFPZ), and trifluoperazine (TFP), were compared for the potency of swelling of normal red cells and antisickling effect of red cell from patients with sickle cell disease. 2. Normal erythrocytes treated with the phenothiazines became swollen within 60 min, and the percent increase in mean cell volume (MCV) was dose-dependent and varied according to the agent used. 3. The cell swelling was hematocrit-dependent, and pH-dependent. A greater swelling potency was seen at lower hematocrits and higher pH values. 4. The swelling was also dependent on the pKa values of these chemicals. TFP with the lowest pKa induced the highest degree of swelling while CPZ with the highest pKa induced the lowest. 5. The un-ionized fraction of the phenothiazines at a given pH was directly related to potency of the swelling. 6. The cell swelling was directly related to the binding affinities of the phenothiazines to calmodulin. 7. The antisickling effect of these compounds using sickle red cells, numerically estimated by an automated image analysis system, was found in the same order as that of swelling potency: TFP > TFPR > CPZ.

A straight path centrifugal blood pump concept in the Capiox centrifugal pump

This article describes comparative studies of a newly developed "straight path" centrifugal pump (Capiox centrifugal pump) targeted for open-heart surgery and circulatory support. A unique straight path design of the rotor was very effective in reducing the pump's rotational speed and prime volume. This pump was evaluated for hydraulics, hemolysis, depriming characteristics, cavitation, and heat generation. Two commercially available centrifugal pumps, the Biomedicus cone-type pump and the Sarns 3M impeller-type pump, were used as controls. The new pump required the lowest pump speed to produce the same flow rates under the same pressure loads and demonstrated the lowest hemolysis and the lowest temperature rise with the outlet clamped. The air volume required to deprime the new pump was one-third to one-half that for the other pumps, and no sign of cavitation was observed even if a small amount of air was introduced to the pump inlet under a negative pressure of 200 mm Hg.

Prognostic factors for well-differentiated squamous cell carcinoma in the oral cavity with emphasis on immunohistochemical evaluation

Histological and immunohistological prognostic factors for well-differentiated oral squamous cell carcinoma (SCC) were examined in 31 patients. They included 18 males and 13 females aged 42-84 (median 63) years. The tumors were located in the tongue in 13 cases, gingiva in 7, floor of the mouth in 5, cheek mucosa in 4, and palate in 2. Advanced disease (stages III and IV) was found in 92% of patients; 22 were treated by radical surgery and nine by excisional or incisional biopsy, followed by adjuvant chemotherapy and external radiation. The 5-year survival rate in patients with stages III and IV disease was 58% and 33%, respectively. Histologic factors evaluated were tumor cell mitotic counts, degree of lymphocyte and eosinophil infiltration around the tumor, mast cell counts, HLA-DR expression on tumor cells, or surrounding lymphocytes. Multivariate analysis revealed that degree of eosinophilic infiltration and expression of HLA-DR antigen on the tumor cells were significant factors for prognosis (P < 0.05); i.e., heavy eosinophilic infiltration and expression of HLA-DR antigen on tumor cells were signs of an unfavorable prognosis. The interpretation of the present findings are discussed with a review of the literature.

[Usefulness and safety of dobutamine stress thallium myocardial scintigraphy]

Pharmaceutical stress test is performed for diagnosis of coronary artery disease in patients who can not perform exercise test. We studied whether high dose dobutamine stress test is useful and safe. Subjects consisted of 133 patients (pts) in doubutamine stress test and 45 pts in exercise test. Dobutamine stress test was initiated by 10 micrograms/kg/min, followed by 10 micrograms/kg/min increment every 3 minutes. Maximal doubutamine dose was 40 micrograms/kg/min for 3 minutes. Endpoints of dobutamine stress were as follows: ST depression equal to or more than (> or =) 0.2 mV: 30 pts, > or = 75% predictive maximum heart rate: 20 pts, > or = 20 mmHg systolic blood pressure fallen: 10 pts, 40 micrograms/kg/min for 3 minutes: 10 pts, chest pain: 7 pts, pressure rate product (PRP) > or = 25,000: 1 patient. Side effects of dobutamine stress test were as follows: palpitation: 52%, arrhythmia: 13%, angina and dyspnea: 7%, headache: 6%. These symptoms were disappeared within 2 minutes. One patient, who performed dobutamine test 2 day after PTCA, had myocardial infarction. At peak of dobutamine stress test, systolic blood pressure, heart rate and PRP were increased similar to exercise test. However, diastolic blood pressure was not changed. The concentration at peak of dobutamine was 25.5 +/- 7.8 micrograms/kg/min. The duration of dobutamine stress test was 7.3 +/- 2.3 minutes. The 65 patients (49%) need more than 20 micrograms/kg/min of dobutamine which was maximal loading dose in previous reports. For diagnosis of coronary artery disease, sensitivity was 91% (31/34) and specificity was 70% (7/10). From these data, high dose dobutamine stress test is useful and relatively safe stress method for diagnosis of coronary disease. This stress test would be performed in patients who can not perform exercise test.

Detection of low copy numbers of Epstein-Barr virus by in situ hybridization using nonradioisotopic probes prepared by the polymerase chain reaction

A highly sensitive in situ hybridization procedure was established using digoxigenin-11-dUTP-labeled probes that were prepared by the polymerase chain reaction (PCR). By using 12 sets of primers, BamHI-W fragment of the Epstein-Barr Virus (EBV) was amplified with labeled substrate in individual PCRs. Then the 12 probes (average size, 120 base pairs) were mixed and hybridized with cultured and RNase-treated Namalwa cells, which contain two copies of EBV genomes per cell. The strength of the signals was much stronger as compared with random-primed probe. Our results indicate that the size-averaged PCR probes magnified the sensitivity for detecting low copy numbers of virus genomes by in situ hybridization and that this technique has the potential for investigating latent virus infection in other clinical situations.

Development of the Terumo Capiox centrifugal pump and its clinical application to open heart surgery: a comparative study with the roller pump

We have developed the Terumo Capiox centrifugal pump (CXP), which consists of a rotor having a unique straight-path design to reduce pump rotational speed without decreasing hydraulic efficiency. The CXP was tested in vitro for blood trauma with a specially designed test circuit using fresh bovine blood. The Biopump (BP) (Medtronic, Minneapolis, MN, U.S.A.) and the roller pump (RP) were used as controls. The CXP demonstrated the smallest elevation of free plasma hemoglobin compared with the BP and the RP. The CXP was then applied to cardiopulmonary bypass (CPB) in 10 patients (CXP group) who underwent elective coronary artery bypass grafting (CABG), and the results were compared with those for a comparable roller pump group (RP group). Free plasma hemoglobin level, platelet count, and serum beta-thromboglobulin (beta-TG) level were measured during CPB. There were no CXP-related complications nor hemodynamic abnormalities during CPB. The CXP group demonstrated less hemolysis and less platelet depletion than the RP group. Furthermore, the serum beta-TG level was significantly lower in the CXP group than in the RP group. The CXP showed excellent hemodynamic performance with less blood trauma both in vitro and in clinical application to open heart surgery. Thus, the CXP has significant potential to be safely applied to CPB for open heart surgery and circulatory support.

Nucleotide sequence of the primer RNA for DNA replication of filamentous bacteriophages

We determined the nucleotide sequence of RNA synthesized in vitro by Escherichia coli RNA polymerase at the complementary-strand replication origin on the single-stranded viral DNA of bacteriophages f1 and IKe (ori-RNA) by using chain-terminating ribonucleoside triphosphate analogs. The results indicated that the start site of f1 ori-RNA synthesis is 20 nucleotides downstream from the site previously reported (K. Geider, E. Beck, and H. Schaller, Proc. Natl. Acad. Sci. USA 75:645-649, 1978) and that the RNA sequence [(5')pppAGGGCGAUGGCCCACUACGU-OH(3')] is complementary to the f1 DNA sequence from nucleotides 5736 to 5717, with minor heterogeneity at the 3' end. IKe ori-RNA had a sequence identical to that of f1 ori-RNA, except for a single base substitution, and IKe RNA was complementary to a region of IKe DNA (from nucleotides 6441 to 6422) that was homologous to the f1 sequence. Phenotypes and ori-RNA sequences in the relevant region of the genome of f1 deletion mutants were consistent with the presently determined sequence of ori-RNA. A possibility that ori-RNA synthesis is initiated by a mechanism similar to that for general transcription is suggested as a result of the new assignment of the ori-RNA start site. The double-origin plasmid assay of minus-strand origin activity, a sensitive in vivo method for detecting cis-acting elements for the initiation of DNA replication on a single-stranded DNA template, is described.