Second allogeneic peripheral blood stem cell transplantation with fludarabine-based low-intensity conditioning regimen for relapsed myelodysplastic syndrome after allogeneic bone marrow transplantation

We describe the case of a 51-year-old patient with relapsed myelodysplastic syndrome after allogeneic bone marrow transplantation (BMT), who underwent allogeneic peripheral blood stem cell transplantation (PBSCT) after conditioning with a novel regimen consisting of fludarabine, busulfan, and antithymocyte globulin. The second PBSCT was performed early, at 3 months after the initial allogeneic BMT, but it was well tolerated and complete hematologic remission was documented. The patient did not experience any early transplantation-related organ toxicity but died from opportunistic infection 6 months after the second transplantation. Our experience suggests that this novel regimen may induce remission and could be offered to patients relapsing after the first transplantation; however, the fludarabine-containing regimen might be accompanied by profound immunosuppression.

Up-regulation of CD44 in rheumatoid chondrocytes

The adhesion molecule CD44 is thought to play an important role in the inflammatory process. To identify the expression of CD44 in articular chondrocytes in rheumatoid arthritis (RA), monoclonal anti-CD44 antibodies were immunohistochemically used to react with articular cartilage specimens of 15 patients with RA, 9 with osteoarthritis (OA), and 6 with femoral neck fracture (FF). The proportion of CD44-positive chondrocytes in RA was 93 +/- 2% (N=16), which was significantly higher than that in OA (59 +/- 7%, N=9, p<0.001) and FF (46 +/- 5%, N=6, p<0.001). Among CD44 isoforms examined, the hemopoietic form was dominant in chondrocytes in RA. Therefore, up-regulation of CD44 on chondrocytes may play a significant role in cartilage degeneration in RA.

Embolization of arteriovenous malformations prior to radiosurgery

SUMMARY

Embolization prior to radiosurgery is useful to reduce the AVM nidus for adequate planning for radiosurgery. In 37 cases we encountered, patients with the least radiosurgical effects had diffuse type nidus, where the feeders embolized with absorbable embolic materials had the possibility of recanalization. The main purpose of embolization is to prevent bleeding while the radiosurgical effects are being fully obtained. Thus, nidus embolization and the occlusion of fistulous feeders, meningeal feeders and intranidal aneurysms using permanent embolic materials are essential, since effective and successful embolization can increase the occlusion rate and shorten the period until complete occlusion following radiosurgery.

Plasmid-encoded metallo-beta-lactamase (IMP-6) conferring resistance to carbapenems, especially meropenem

In 1996, Serratia marcescens KU3838 was isolated from the urine of a patient with a urinary tract infection at a hospital in northern Japan and was found to contain the plasmid pKU501. Previously, we determined that pKU501 carries bla(IMP) and the genes for TEM-1-type beta-lactamases as well as producing both types of beta-lactamases (H. Yano, A. Kuga, K. Irinoda, R. Okamoto, T. Kobayashi, and M. Inoue, J. Antibiot. 52:1135-1139, 1999). pKU502 is a recombinant plasmid that contains a 1.5-kb DNA fragment, including the metallo-beta-lactamase gene, and is obtained by PCR amplification of pKU501. The sequence of the metallo-beta-lactamase gene in pKU502 was determined and revealed that this metallo-beta-lactamase gene differed from the gene encoding IMP-1 by one point mutation, leading to one amino acid substitution: 640-A in the base sequence of the IMP-1 gene was replaced by G, and Ser-196 was replaced by Gly in the mature enzyme. This enzyme was designated IMP-6. The strains that produced IMP-6 were resistant to carbapenems. The MICs of panipenem and especially meropenem were higher than the MIC of imipenem for these strains. The k(cat)/K(m) value of IMP-6 was about sevenfold higher against meropenem than against imipenem, although the MIC of meropenem for KU1917, which produced IMP-1, was lower than that of imipenem, and the MIC of panipenem was equal to that of imipenem. These results support the hypothesis that IMP-6 has extended substrate profiles against carbapenems. However, the activity of IMP-6 was very low against penicillin G and piperacillin. These results suggest that IMP-6 acquired high activity against carbapenems, especially meropenem, via the point mutation but in the process lost activity against penicillins. Although IMP-6 has reduced activity against penicillins due to this point mutation, pKU501 confers resistance to a variety of antimicrobial agents because it also produces TEM-1-type enzyme.

Reduced-dose chop therapy for elderly patients with non-Hodgkin's lymphoma

While CHOP therapy is effective for malignant lymphoma, the optimum schedule for elderly patients remains controversial. The present study investigated the usefulness of reduced-dose CHOP therapy for elderly patients. Previously untreated patients aged 65 years or older with intermediate to high-grade non-Hodgkin's lymphoma were given up to 6 courses of reduced-dose CHOP therapy at 3-week intervals. Group A patients were given (5/6) of the standard dose and Group B received 7/12 of the standard dose. Filgrastim was administered when the white blood cell count fell below 2,000/microL. Fifty-seven patients were evaluable and the scheduled therapy was completed in 37. For patients aged from 65 to 79 years and for patients older than 80 years, the complete response rate was 79.5% and 46.2%, overall 3-year survival was 58.2% and 30.4%, and event-free 3-year survival was 49.3% and 44.4%, respectively. Major toxicities (> or = grade 3) included leukopenia in 42 patients and documented infection in 7 patients. Grade 3 cardiac plus renal failure, grade 3 peritonitis due to small bowel perforation, and grade 3 liver dysfunction occurred in 1 patient each. One patient died of toxicity (grade 4 hematological toxicity and pneumonia). In conclusion, it seems that in the elderly patients with non-Hodgkin's lymphoma, response to reduced-dose ((5/6) dose) CHOP therapy is comparable to that for standard CHOP in younger adults, mainly because of improved dose-intensity.

[AmpC beta-lactamases producing bacteria]

beta-Lactamases are the principal mechanism of bacterial resistance to beta-lactam antibiotics. In recent years, resistance due to production of beta-lactamases including extended-spectrum beta-lactamses, carbapeneases and AmpC beta-lactamses, has risen at alarming rate in clinical isolates of gram-negative bacteria. AmpC beta-lactamses are classified by whether genes locate on chromosome or plasmid. The purpose of this paper is to address the general mechanism involve in AmpC beta-lactamase production and the clinical importance of the enzymes.

Studies on the constituents of Broussonetia species VIII. Four new pyrrolidine alkaloids, broussonetines R, S, T, and V and a new pyrroline alkaloid, broussonetine U, from Broussonetia kazinoki Sieb

Four new pyrrolidine alkaloids, broussonetines R, S, T, and V and a new pyrroline alkaloid, broussonetine U were isolated from the branches of Broussonetia kazinoki SIEB. (Moraceae) in low yield. Broussonetines R, S and T were formulated as (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R)-1-hydroxy-3-[6-(4-hydroxybutyl)-cyclohexy-2-on-1(6)-enyllpropyl] pyrrolidine (1), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R,10S)-1,10,13-trihydroxytridecyl] pyrrolidine (2), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R,5S)-1,5, 13-trihydroxy-10-oxo-tridecyl] pyrrolidine (3). And broussonetines U and V were proposed to be (2S,3S,4S)-2-hydroxymethyl-3, 4-dihydroxy-5-(9-oxo-13-hydroxytridecyl)-5-pyrroline (4), (2R,3S,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(E)-9-oxo-13-hydroxy-3-tridecenyl] pyrrolidine (5), respectively, by spectroscopic and chemical methods.

Homogenous implant in rat tibias of matrix preserved in 98% glycerin: histomorphologic study

As a chemical medium for preservation of tissues, glycerin has shown good results because it maintains the cellular integrity despite the tissue dehydration it causes. Taking advantage of the osteoinducing properties of the osseous matrix and glycerin as a proper medium for tissue preservation, osseous matrix was implanted in rat tibias. Twenty-four rats were used, each receiving two surgical wounds. In one of the wounds an osseous matrix preserved in 98% glycerin was implanted and the other received a matrix without preservatives. Six animals were sacrificed on days 10, 20, 30 and 60 post-implant. After routine histological processing, the specimens were stained in hematoxylin-eosin and Masson's trichrome. The results showed that the matrixes preserved in glycerin presented faster resorption with replacement by newly formed tissue.

Laparoscopic findings in primary sclerosing cholangitis

BACKGROUND AND STUDY AIMS

Primary sclerosing cholangitis (PSC) is a cholestatic disease characterized by segmental narrowing and dilatation of bile ducts. Few studies have been performed on the laparoscopic findings associated with this disease, and the present study was intended to assess the usefulness of laparoscopy for the diagnosis and staging of PSC.

PATIENTS AND METHODS

Six patients were examined by laparoscopy with liver biopsy. Repeated laparoscopy was performed in three patients.

RESULTS

Laparoscopy revealed coarse surface irregularity and discoloration. Surface irregularity was classified into four grades: smooth, shallowly depressed, undulated, and nodular. The affected area showed whitish yellow discoloration. The discolored area was demonstrated as a poorly stained area by intravenous injection of indocyanine green (ICG). Lobular markings became apparent because of the yellow color change in the portal tract, resulting in a leopardskin-like appearance. Lymph-vessel dilatation was seen in advanced stages. Repeated laparoscopy of a patient without treatment demonstrated a progression from a smooth surface to a shallow depression with leopardskin-like markings. On the other hand, the two patients treated with immunosuppressive agents showed improvement of liver swelling and disappearance of the leopardskin-like markings and lymph-vessel dilatation.

CONCLUSIONS

Laparoscopy may provide useful information for the diagnosis and staging of PSC.

Molecular cloning and analysis of the 5'-flanking region of the human MYPT1 gene

We have cloned and sequenced a 5 kb genomic fragment in the 5'-flanking region of the human myosin phosphatase target subunit 1. The transcription initiation site (+1) was 268 bp upstream from the translation start site. In this promoter there are no canonical TATA or CAAT box elements but there is a high GC-rich sequence. Basal promoter activity was due to the GC-rich region that contained one Sp1 transcription factor binding site, thus demonstrating that the MYPT1 gene is a housekeeping gene. Luciferase reporter assays showed the presence of two regions for positive elements and one for a negative element.

Aberrant expression of cytokeratin 7 as a histological marker of progression in primary biliary cirrhosis

AIM

We evaluated the aberrant expression of cytokeratin 7 (CK-7) in hepatocytes as a marker of cholestasis and progression in primary biliary cirrhosis (PBC).

PATIENTS AND METHODS

The expression of CK-7 was studied by immunohistochemistry in 83 cases of PBC. This expression was compared with biochemical data, the deposition of copper-associated protein, and previous histological classifications.

RESULTS

In normal liver, CK-7 was expressed exclusively in bile duct epithelial cells (BDE). In PBC, the expression was also observed in hepatocytes. The expression pattern was classified as follows: Grade 0, BDE as in normal; Grade 1, proliferated bile ductules; Grade 2, periportal hepatocytes in addition to proliferated bile ductules; Grade 3, intralobular hepatocytes; Grade 4, the majority of hepatocytes. The grades correlated with serum bilirubin levels but not with serum levels of biliary enzymes. A discrepancy between the CK-7 grading and Ludwig's classification was noted in cases with Stage 1 of the CK-7 grading who were considered Stage 2 or 3 in Ludwig's classification, suggesting that cholestasis and inflammatory activity might be independent events.

CONCLUSIONS

These results suggest that the aberrant expression of CK-7 in hepatocytes may be a marker of chronic cholestasis and progression in PBC.

Detection of doxorubicin cardiotoxicity by using iodine-123 BMIPP early dynamic SPECT: quantitative evaluation of early abnormality of fatty acid metabolism with the Rutland method

BACKGROUND

To evaluate the possibility of predicting the development of doxorubicin-induced cardiomyopathy, we performed quantitative assessment of the early kinetics of iodine-123 beta-methyl-iodophenyl-pentadecanoic acid (I-123 BMIPP) by means of dynamic myocardial SPECT.

METHODS

Thirty-six patients with various malignancies were examined. I-123 BMIPP dynamic myocardial SPECT was performed before chemotherapy, after chemotherapy, or both. Immediately after the injection of I-123 BMIPP (111 MBq), 30-second dynamic SPECT data were acquired successively for 15 minutes. The left ventricular (LV) myocardium was divided into 8 segments in short-axial and vertical slices. By using the time-activity curve (TAC) of each myocardial segment [Mo(t)] as an output function and the TAC of the LV cavity [B(t)] as an input function, the Rutland equation, Mo(t)/B(t)= F + K Integral of(B(t)dt/B(t)), was used as a means of assessing all segments.

RESULTS

Mo(t)/B(t) showed a good linear correlation with Integral of(B(t)dt/B(t)) from 30 seconds to 4 minutes in all 456 segments. The mean K value of 8 LV segments was significantly lower after chemotherapy than before chemotherapy (0.071+/-0.019 [n = 21] vs. 0.095+/-0.025 [n = 36], P<.001). In 21 patients in whom dynamic SPECT was performed both before and after chemotherapy, the mean K values of left ventricle showed a significant decrease, from 0.101+/-0.024 to 0.071 +/-0.019 (P<.0001). The fractional change in the value of K after chemotherapy showed a significant linear correlation with the administered dose of doxorubicin (r = 0.648, P<.002).

CONCLUSION

I-123 BMIPP dynamic myocardial SPECT may be clinically useful, because it permits the early detection of doxorubicin-induced cardiomyopathy.

Oxidation products of uric acid and ascorbic acid in preterm infants with chronic lung disease

Allantoin, the oxidation product of uric acid (UA), can be used as an in vivo marker of free radical generation. The aims of the present study were to evaluate the allantoin changes in plasma and bronchoalveolar lavage fluid (BALF) as well as to examine plasma levels of ascorbic acid (AA) and its oxidation product, dehydroascorbic acid (DHAA), in infants with or without chronic lung disease (CLD) during the first week of life. The study population was 20 infants of 24-30 weeks gestation, comprising 10 who subsequently developed CLD and 10 without CLD. In the CLD infants, the plasma allantoin/UA ratio showed a significant increase after day 1 and continued to increase gradually to reach a peak on day 6 (6.5 +/- 4.1% for CLD and 2.1 +/- 0.9% for non-CLD infants). The allantoin/UA ratio in BALF was also higher in CLD infants and the difference reached significance on days 4-6 (41.2 +/- 15.8% for CLD and 11.7 +/- 9.9% for non-CLD infants). In contrast to allantoin, the plasma DHAA/AA ratio did not differ between the 2 groups throughout the study period. Our findings that the allantoin/UA ratios were significantly higher in CLD than non-CLD infants not only in plasma but also in BALF, and that the intergroup differences of this ratio in both plasma and BALF was more prominent in the latter half of the first week of life further confirm our previous speculation that oxygen radicals are involved in the development of neonatal CLD.

[Antibacterial activity of 16 antibiotics against Helicobacter pylori]

The susceptibilities of 24 Helicobacter pylori isolates, which were originated from clinical materials, to 5 beta-lactam antibiotics [benzylpenicillin (PCG), ampicillin (ABPC), cephalothin (CET), ceftazidime (CAZ), cefotiam (CTM) and imipenem (IPM)], two macrolides [clarithromycin (CAM) and rokitamycin (RKM)], two aminoglycosides [amikacin (AMK) and gentamicin (GM)], two new quinolones [ciprofloxacin (CPFX) and levofloxacin (LVFX)], two tetracycline [tetracycline (TC) and minocycline (MINO)], rifampicin (RIF) and chloramphenicol (CP) were tested. All of the isolates showed similar susceptibilities against beta-lactam antibiotics. However, MICs of CTM and CAZ were two- to four-fold higher than those of PCG, ABPC, CET and IPM, MICs of rokitamycin for the tested strains were higher than those of clarithromycin. MICs of CPFX and LVFX showed two-modal distributions. The first peak of distributions was observed between 0.06 to 0.5 microgram/ml and second one was between 4 to 16 micrograms/ml. These distributions suggested that MIC values of 4 to 16 micrograms/ml could result from the expression of a resistance mechanism. In addition, some of H. pylori strains were observed drug resistances between CP and AMK, new quinolones and AMK respectively. From the molecular epidemiological study, cryptic plasmids were detected from the 3 isolates among 24 strains tested.

The skin of atopic dermatitis patients contains a novel enzyme, glucosylceramide sphingomyelin deacylase, which cleaves the N-acyl linkage of sphingomyelin and glucosylceramide

We have demonstrated previously that there is an abnormal expression of sphingomyelin (SM) deacylase in the epidermis of patients with atopic dermatitis (ADe). In the present study, we have prepared N-[palmitic acid-1-(14)C]SM and N-[palmitic acid-1-(14)C]glucosylceramide (GCer) to use as substrates and have quantified SM deacylase activity by detecting the release of [(14)C]palmitic acid in extracts of the stratum corneum or the epidermis of ADe patients. In studies using [palmitic acid-1-(14)C]SM as a substrate, a pH dependency of catalytic activity with a peak at pH 5.0 was found. Preparative SDS/PAGE using an extract of ADe epidermis revealed that the molecular mass of SM deacylase is 40000 Da, which is consistent with its apparent molecular mass of 42000 Da estimated by gel-filtration analysis of stratum corneum extracts. Analytical isoelectric focusing (IEF) chromatography demonstrated that the pI values of SM deacylase, beta-glucocerebrosidase (GlcCDase), sphingomyelinase (SMase) and acid ceramidase were 4.2, 7.4, 7.0 and 5.7, respectively. In enzymic analysis using pI-4.2 SM deacylase partially purified by IEF, which had no detectable contamination with acid ceramidase, GlcCDase or SMase, radio-TLC analysis revealed that radiolabelled sphingosylphosphocholine or [1-(14)C]palmitic acid was enzymically liberated from [choline-methyl-(14)C]SM or N-[palmitoyl-1-(14)C]GCer, respectively, used as substrates. Further the pI-4.2 protein purified from extracts of the stratum corneum of ADe patients was able to hydrolyse N-[palmitoyl-1-(14)C]SM and GCer, but not N-[palmitoyl-1-(14)C]ceramide. These results indicate that a hitherto undiscovered epidermal enzyme, termed here glucosylceramide sphingomyelin deacylase, is expressed in the skin of ADe patients, which plays an important role in ceramide deficiency (including acylceramides) in the stratum corneum.

High-expression of sphingomyelin deacylase is an important determinant of ceramide deficiency leading to barrier disruption in atopic dermatitis

We have previously demonstrated that there is abnormal expression of sphingomyelin (SM) deacylase-like enzyme in the epidermis of patients with atopic dermatitis (AD), which results in decreased levels of ceramides in their involved and uninvolved stratum corneum. For quantitation of the expression of SM deacylase in AD, we synthesized 16-(9-anthroyloxy) hexadecanoylsphingosylphosphorylcholine or [palmitic acid-14C] SM and used them as substrates to directly measure the activity of SM deacylase by detecting the release of labeled free fatty acid. Direct enzymatic measurements demonstrated that stratum corneum from lesional forearm skin (volar side) of AD patients has an extremely high SM deacylase activity that is at least five times higher than in the stratum corneum from healthy controls. In stratum corneum from nonlesional skin of AD patients, SM deacylase activity is still at least three times higher than in healthy controls. In contrast, stratum corneum from contact dermatitis patients shows levels of SM deacylase similar to healthy controls. In extracts of whole epidermis biopsies from AD patients, SM deacylase activities are significantly (3-fold) increased over healthy controls in the particulate fraction, whereas there is no significant difference in the activity of sphingomyelinase between AD and healthy control. In peripheral blood lymphocytes of AD patients, there is no increase in activity compared with healthy controls, indicating a possibility that the high expression of SM deacylase is highly associated with the skin of AD patients. These findings suggest that, in contrast to changes in sphingolipid metabolism due to aging, the hitherto undiscovered enzyme SM deacylase, is highly expressed in the epidermis of AD patients, and competes with sphingomyelinase or beta-glucocerebrosidase for the common substrate SM or glucosylceramide, which leads to the ceramide deficiency of the stratum corneum in AD.

[In vitro antibacterial activity of prulifloxacin, a new oral quinolone, and comparative susceptibility rate at clinical breakpoint MIC]

In vitro drug sensitivity of clinically isolated bacteria against prulifloxacin (PUFX), which is a new quinolone, was investigated, and the antibacterial activity and susceptibility rate at clinical breakpoint were compared with those of norfloxacin, ofloxacin (OFLX), ciprofloxacin, tosufloxacin, fleroxacin, sparfloxacin and levofloxacin (LVFX). The following results were obtained. 1) PUFX showed a broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. 2) MIC80 of PUFX was 0.25 and 1 microgram/ml, against methicillin susceptible Staphylococcus aureus and Streptococcus pneumoniae, respectively and below 0.125 microgram/ml against Gram-negative Enterobacteriaceae. MIC90 of PUFX against Pseudomonas aeruginosa, which has MIC not exceeding 4 micrograms/ml to OFLX, was 0.5 microgram/ml. 3) PUFX was judged as active against the bacteria under the criteria proposed presented by "the Sensitivity Determination Committee for Antibiotics, Japan Society of Chemotherapy: Break Point for Respiratory Infectious Diseases and Sepsis". It is suggested that the sensitivity of each bacterial species to PUFX was high. 4) From the correlation analysis of MIC, PUFX was shown to have two to eight times higher antibacterial acitivity than LVFX for Citrobacter freundii, Serratia marcescens and Pseudomonas aeruginosa. 5) PUFX showed potent short-time bactericidal activity against S. aureus and P. aeruginosa.

Expression of perforin and Fas ligand mRNA in the liver of viral hepatitis

Cytotoxic T lymphocytes (CTLs) play an important role in the pathogenesis of viral hepatitis. We studied the expression of mRNAs of perforin and Fas ligand (Fas-L) in biopsy specimens from chronic hepatitis B (CHB) (15 cases) and hepatitis C (CHC) patients (13 cases). Both perforin and Fas-L mRNAs were detected in all cases of both CHB and CHC. No messages were detected in the control livers from two cases of fatty liver, a case of Gilbert's syndrome, and a case of Dubin-Johnson syndrome. Semiquantitative analysis revealed a positive correlation between the intensity of perforin and Fas-L mRNAs in both CHB and CHC. In CHB, the intensity of both perforin and Fas-L mRNAs showed a positive correlation with the histological activity and serum alanine aminotransferase level, while the correlation was not apparent in CHC. These results suggest that both perforin and Fas/Fas-L systems are involved in the pathogenesis of liver cell injury of CHB and CHC.

[Clinical features of patients with osteoarthritic knees followed by development of rheumatoid arthritis]

We investigated clinical features of patients with osteoarthritic knees followed by development of rheumatoid arthritis (RA) after several year's interval. The subjects were 16 knees of 8 patients with osteoarthritis (OA) including one man and 7 women. The mean age at development of OA knee was 62.8 years (range; 45-73). The mean age at later development of RA was 66.0 years (range; 52-79). The mean follow-up period was 96.4 months (range; 28-191). We evaluated clinical features using the 1987 revised Criteria of the American College of Rheumatology (ACR), laboratory dates including RF, CRP, ESR, the number of joints with RA, and femorotibial angle (FTA). The mean number of features of patients which was fulfilled with the ACR criteria was 3.3 +/- 1.6 at the onset of RA. Only four patients were seropositive through the total follow-up period. The serum level of RF, CRP, and ESR were reduced at the follow-up period. The mean number of the joints involved in RA was 11.0 +/- 5.1 (range; 4-22) and wrist and shoulder joints were involved more frequently than other joints except knees. High tibial osteotomy (HTO) was performed on 5 knees of 3 patients and the mean degree of FTA was 168.8 +/- 1.9 degrees just after surgery. However, 36 months after development of RA, joint destruction and valgus deformity occurred on 3 knees and the mean degree of FTA of 5 knees was ended up to 159.6 +/- 11.3 degrees. Our experiences suggested that RF, CRP, ESR and lesions of other joints should be carefully evaluated in the OA patients with seropositivity or knee hydrarthrosis and that histological analysis for synovium should be assessed by the biopsy at time of HTO or arthroscopic surgery to improve accuracy of diagnosis.

[Assessment of most appropriate background subtraction method for quantification of 123I-metaiodobenzylguanidine (MIBG) myocardial uptake by comparing with plasma ANP and BNP]

BACKGROUND

Quantification of 123I-metaiodobenzylguanidine (MIBG) myocardial uptake is widely accepted as a useful tool for estimating the severity of congestive heart failure. However, most reliable method has not been determined yet because of the difficulty of background (BG) subtraction. In this study, the most appropriate BG subtraction method was evaluated as compared with plasma atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), norepinephrine (NEP) and left ventricular ejection fraction (LVEF).

METHODS

Twenty-one patients with chronic heart failure were examined. After bolus injection of 123I-MIBG (111 MBq), dynamic anterior chest images were collected every second for 2 minutes. Planar anterior chest images were obtained 15 minutes (early image) and 4 hours later (delayed image) respectively. The parameters for quantification of 123I-MIBG myocardial uptake used in this study were heart to mediastinum ratio (H/M), myocardial washout rate and uptake ratio. Background was calculated using the region of interest (ROI) placed over a part of upper mediastinum, whole upper mediastinum, right lung and pericardial space respectively. The values of these parameters were calculated with and without BG subtraction and compared with plasma ANP, BNP and others.

RESULTS

H/M did not correlate with ANP or BNP. Myocardial washout rate without BG subtraction showed significant correlation with ANP (p < 0.01) and BNP (p < 0.05). After BG subtraction employing ROI placed over the part of upper mediastinum and whole upper mediastinum, myocardial washout rate showed better correlation with BNP (p < 0.01). Myocardial uptake ratio did not showed any correlation with ANP or BNP without BG subtraction. However, myocardial uptake ratio showed significant correlation with BNP (p < 0.05) after subtraction of upper mediastinal BG. BG subtraction using ROI over right lung or pericardial area revealed poor results in both myocardial washout rate- and uptake ratio.

CONCLUSION

BG subtraction using ROI over the upper mediastinum is likely to be suitable for quantitative analysis of 123I-MIBG myocardial scintigram.

Aorto-coronary dissection during angioplasty in a patient with myxedema

A 67-year-old man with overt hypothyroidism and medically controlled hypertension was admitted for coronary angiography because of exertional angina. His triiodothyronine (T3) and thyroxine (T4) levels had been low for 4 years. Although signs and symptoms of hypothyroidism were apparent, his hypercholesterolemia was mild. Coronary angiography revealed an eccentric stenosis in the distal portion of the right coronary artery and it was decided to perform angioplasty because his angina had continued in spite of medication. The dissection appeared at the lesion site after the first nominal inflation, and a subsequent image disclosed a spiral dissection from the dilated site to the aortic sinus and peripheral coronary artery. Although emergency stenting could not prevent the extension near the origin of the brachiocephalic artery, the false lumen thrombosed and then diminished with conservative therapy. Aorto-coronary dissection is potentially life-threatening and has been recently reported as a complication during cardiac catheterization procedures. Chronic hypothyroid insufficiency may be one of the risk factors for this complication.

ampR gene mutations that greatly increase class C beta-lactamase activity in Enterobacter cloacae

The ampC and ampR genes of Enterobacter cloacae GN7471 were cloned into pMW218 to yield pKU403. Four mutant plasmids derived from pKU403 (pKU404, pKU405, pKU406, and pKU407) were isolated in an AmpD mutant of Escherichia coli ML4953 by selection with ceftazidime or aztreonam. The beta-lactamase activities expressed by pKU404, pKU405, pKU406, and pKU407 were about 450, 75, 160, and 160 times higher, respectively, than that expressed by the original plasmid, pKU403. These mutant plasmids all carried point mutations in the ampR gene. In pKU404 and pKU405, Asp-135 was changed to Asn and Val, respectively. In both pKU406 and pKU407, Arg-86 was changed to Cys. The ease of selection of AmpR mutations at a frequency of about 10(-6) in this study strongly suggests that derepressed strains, such as AmpD or AmpR mutants, could frequently emerge in the clinical setting.

[New combination therapies for gastrointestinal cancer]

Recently, cisplation (CDDP) and CPT-11 have joined the other drugs used for gastrointestinal chemotherapy, and the combination of I-leucovorin (I-LV)/5-FU has become available for use in medical treatment in Japan. This enables doctors to make a variety of regimens for gastrointestinal cancers. In this paper, we explain the new combinations, especially LV/5-FU/platinum, CPT-11/CDDP, and LV/5-FU/CPT-11. The combination of 5-FU/LV/CPT-11 has shown a higher antitumor activity than 5-FU/LV alone, with increased progression free survival or time-to-treatment failure. This combination will be considered the new standard regimen for colorectal cancer. It is worthy of note that the combination of UFT/LV provided on equally effective but safe and more convenient oral alternative to the standard i.v. 5-FU/LV regimen for colorectal cancer.

Acute myocardial infarction in a patient with anomalous left coronary artery origin and primary antiphospholipid syndrome

Anomalous left main coronary artery (LMCA) originating from the right coronary sinus and running between the aorta and pulmonary trunk is a rare congenital condition. Although this disease is known to be associated with myocardial infarction and sudden death, the precise mechanism is uncertain. A 14-year-old male with this anomaly developed myocardial infarction during exercise complicated by primary antiphospholipid syndrome. He was admitted to hospital with persistent chest pain and sudden cardiac collapse that occurred while he was running. Cardiac catheterization demonstrated a narrowed segment in the LMCA and impaired blood flow, prompting a diagnosis of extensive anterior myocardial infarction. Emergency bypass surgery was performed using a single saphenous vein graft to the left anterior descending artery. Postoperative angiography showed the presence of an anomalous LMCA arising from the right sinus of Valsalva and running between the great vessels. The aortic samples were pathologically normal. He was discovered to also have primary antiphospholipid syndrome and was discharged without symptoms after warfarin therapy. Complicated primary antiphospholipid syndrome may trigger myocardial infarction in asymptomatic patients with this type of coronary anomaly.