Detection of Two Biotypes of Liriomyza chinensis (Diptera: Agromyzidae) in Japan

The larva of stone leek leafminer, Liriomyza chinensis (Kato), is known to infest alternately just below the epidermis and inner surface of hollow cylindrical leaves of allium crops, resulting in the formation of discontinuous linear mines (mine form: discontinuous). However, after the fall of 2016, a novel mine form of the same species (mine form: continuous) was detected in Welsh onion fields of Kyoto Prefecture, Japan. We hypothesized that these mine forms were associated with flies having different genetic backgrounds; hence, we compared the mine forms and the partial mtCOI gene of flies collected from Welsh onion fields from 2018 to 2019. The results demonstrated that the flies that emerged from different mine forms could be classified into two haplogroups, i.e., flies displaying a discontinuous mine form were of haplogroup A, whereas those that displayed continuous mines were of haplotype B. Additionally, using populations of these flies reared in the laboratory, we confirmed that the mine form of the larvae of haplotype A on Welsh onions was discontinuous, whereas that of haplotype B was continuous. We named the population that exhibited a discontinuous mine form as biotype A and the population displaying a continuous mine form as biotype B.

Species Composition of Alate Aphids (Hemiptera: Aphididae) Harboring Potato Virus Y and the Harbored Virus Strains in Hokkaido, Northern Japan

Many studies have evaluated transmission abilities of laboratory-reared aphids for potato virus Y (PVY), but few have focused on PVY-harboring species of field-collected aphids and the strains of PVY harbored by aphids. In the present study, we collected alate aphids in yellow pan traps in potato fields with Japanese commercial cultivars in Hokkaido, northern Japan in single 24-h periods during the tuber bulking stage and examined whether individual whole aphids harbored PVY by nested RT-PCR. PVY-positive individuals were identified to species using the gene sequence for cytochrome c oxidase subunit I and, when needed, morphological data and distribution records. In addition, individual strains of PVY harbored were determined using partial sequences of coat protein. Among 1,857 aphids trapped, 195 aphids had PVY and comprised 19 species; 17 species were identified to species-group taxa. Most of the aphid species detected as PVY positive colonize weeds that are common around potato fields in Hokkaido. Five species-group taxa had not been reported previously as a vector aphid of PVY and might be new PVY-vector species. PVYNTN was most frequently detected from PVY-positive aphids as found recently in PVY-infected potatoes in commercial fields in Hokkaido. Two or three PVY strains were rarely detected from a single aphid, and no obvious difference was found in the proportion of the harbored PVY strains among positive aphid species. The first documentation of the species composition of PVY-harboring aphids and the strains of PVY harbored in East Asia should aid understanding of the epidemiology of PVY in Japan.

Abstract P4-21-25: The importance of hormone receptor status on biomarker expression and the efficacy of lapatinib plus capecitabine therapy after progression on trastuzumab in HER2 positive recurrent and advanced breast cancer

Background: Anti-HER2 treatment using trastuzumab (Tmab) has contributed to improving the clinical outcome of HER2-positive breast cancerpatients. However, some patients do not respond to Tmab therapy and the combination of Lapatinib and capecitabine (LC) is an effective treatment option after progression on Tmab. Hormone receptor status is also an important factor for deciding if the patient should be treated with endocrine therapy as well. The aim of this study was to investigate the clinical significance of hormone receptor status in biomarker expression and to evaluate the efficacy of lapatinib therapy.

Materials and Methods: Eighty patients with HER2 positive breast cancer refractory to Tmab were enrolled in this prospective trial (KBC-SG 1107) between December 2011 and March 2014. The following treatment began after enrollment; lapatinib 1250-mg tablets were administered orally once daily and capecitabine (2000 mg/m2 per day) on days 1 to 14 every 21 days until disease progression or until severe adverse events. Total HER2 (H2T), p95HER2 (p95), and total HER3 (H3T) expression levels were quantified in formalin-fixed paraffin embedded samples using VeraTag assays. ER and progesterone receptor (PgR), PTEN and p95 expressions were evaluated using immunohistochemistry (IHC) and PIK3CA mutation using direct sequencing. Statistical analyses were performed using SPSS (ver. 21). A two-sided P<0.05 was considered a statistically significant difference.

Results: The ER- and PgR-positive rates were 55.0% and 33.8%, respectively. The response rate to LC was 30% (CR: 1 case; PR: 23 cases), the clinical benefit rate was 51.3% and the median progression-free survival (PFS) was 174.5 days. Both ER and PgR negativity significantly correlated with higher H2T (cutoff: 13.8), p95HER2 (cutoff: 2.8) and PTEN expression levels (cutoff: H score of 100). Lower H2T expression levels and PIK3CA mutation rates were often observed in the non-responders (both: p=0.087). The ER and PgR status did not correlate with response. A high p95 and PTEN expression significantly correlated with longer PFS in ER and/or PgR positive cases (p=0.02 and 0.03), respectively. The overall survival (OS) after LC significantly correlated with the number of recurrence organs (p=0.0002) but not with the p95 and PTEN expression levels.

Conclusion: LC therapy was effective in Tmab-refractory HER2 positive breast cancer. Moreover, the biomarker expression differed depending on the ER/PgR status and a high p95 and PTEN expression correlated with longer PFS in ER and/or PgR positive cases. Further study is necessary to validate these findings.

Citation Format: Arima N, Nishimura R, Toh U, Tanaka M, Saimura M, Okumura Y, Saito T, Tanaka T, Teraoka M, Shimada K, Koga T, Kurashita K, Todoroki H, Ueo H, Ohi Y, Toyoshima S, Mitsuyama S, Tamura K. The importance of hormone receptor status on biomarker expression and the efficacy of lapatinib plus capecitabine therapy after progression on trastuzumab in HER2 positive recurrent and advanced breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-25.

Population survey of phytoseiid mites and spider mites on peach leaves and wild plants in Japanese peach orchard

A population survey of phytoseiid mites and spider mites was conducted on peach leaves and wild plants in Japanese peach orchards having different pesticide practices. The phytoseiid mite species composition on peach leaves and wild plants, as estimated using quantitative sequencing, changed during the survey period. Moreover, it varied among study sites. The phytoseiid mite species compositions were similar between peach leaves and some wild plants, such as Veronica persica, Paederia foetida, Persicaria longiseta, and Oxalis corniculata with larger quantities of phytoseiid mites, especially after mid-summer. A PCR-based method to detect the ribosomal ITS sequences of Tetranychus kanzawai and Panonychus mori from phytoseiid mites was developed. Results showed that Euseius sojaensis (specialized pollen feeder/generalist predator) uses both spider mites as prey in the field.

Phytoseiid mite species composition in Japanese peach orchards estimated using quantitative sequencing

We attempted a population survey of spider mites and phytoseiid mites in Japanese peach orchards with different pesticide practices; however, we had difficulty discriminating phytoseiid mites. To estimate phytoseiid mite species composition, ribosomal gene fragments were amplified from genomic DNA of five phytoseiid mite species using PCR. Cloning and nucleotide sequencing of amplified fragments identified species-specific polymorphic sites. Newly amplified fragments from recombinant plasmids were mixed in various ratios to produce standard DNA template mixtures. After direct sequencing, the signal ratios between two nucleotides at each species-specific polymorphic site were calculated and shown against the corresponding expected ratios. Quadratic regression equations were used to estimate the phytoseiid mite species composition. Results showed that the phytoseiid mite species composition changed during the survey period and varied among study sites.

PMDA's challenge to accelerate clinical development and review of new drugs in Japan

In recent years, Japan's Pharmaceuticals and Medical Devices Agency (PMDA) has conducted several projects to shorten drug development and review times in Japan to resolve the "drug lag." Key to achieving this goal is greater involvement by the PMDA in drug development through enhancement of scientific consultation and improvement of the review process by reinforcing the operational system, including hiring more reviewers. We discuss here the current projects of the PMDA as well as future challenges.

Participation of elderly patients in registration trials for oncology drug applications in Japan

BACKGROUND

The objective of this study was to evaluate the age-based enrollment of cancer patients into registration trials of new drug applications or expanding the indications for use.

MATERIALS AND METHODS

The data from 234 registration trials in Japan and overseas of 43 drugs, which were reviewed by the Pharmaceuticals and Medical Devices Agency and approved by the Ministry of Health, Labour and Welfare in Japan between 1999 and 2008, were retrospectively analyzed according to the age distribution of enrolled patients. The age distribution of the Japanese cancer population was derived from Cancer Statistics in Japan 2003 and Annual Report on Health, Labour and Welfare 2003-2004.

RESULTS

In the Japanese cancer population, the estimated median age of cancer patients is 70 years, and 66% of cancer patients are aged 65 years or more. The estimated median age of cancer patients in all registration trials conducted in Japan was 59 years, whereas it was 55 years in the registration trials conducted overseas. The proportion of patients aged 65 years or more enrolled in registration trials conducted in Japan was 35%; this number was 28% in registration trials conducted overseas.

CONCLUSION

Elderly patients are underrepresented in oncology registration trials in Japan.

Effects of starvation on reproduction of the predacious mite Neoseiulus californicus (Acari: Phytoseiidae)

Effects of starvation on gravid females of Neoseiulus californicus were investigated at 20 degrees C and 85% RH. When females that had been reared with abundant prey were swapped, just after laying their first egg, to conditions without any prey and water, they laid 1.8 eggs and survived for 4.3 days. In the body of well-fed females, an egg with eggshell and/or two oocytes were observed in the ventral and dorsal regions, respectively. The larger oocyte had two roundish nuclei and abundant yolk granules, and was enveloped with a vitelline membrane. These two nuclei were not fused but were just close to each other. The smaller oocyte had a nucleus, but had not yet formed yolk granules and vitelline membrane. Females after 12 h starvation had an egg in the ventral region and an oocyte in the dorsal region of the body. After more than 24 h starvation females maintained an oocyte in the dorsal region of the body, but had no egg in the ventral region. The oocyte was filled with abundant yolk granules and contained two irregular nuclei when females were starved for 24 h, but when starved for more than 36 h it contained one irregular nucleus. These findings suggest that (1) gravid females maintained an oocyte in the dorsal region after laying two eggs during starvation, (2) the oocyte was not absorbed during starvation, (3) the oocyte advanced vitellogenesis and the fusion of two nuclei, and (4) the vitellogenic oocyte was not enveloped with an eggshell and had not started embryogenesis.

Phase II study of an epirubicin and docetaxel (ET) combination as pre and post-operative systemic therapy in patients with early stage breast cancer (EBC)

10660

Background: The goal of chemotherapy (CT) for EBC is to achieve a high pathologic complete response (CR) leading to an increase in the rate of breast conserving surgery (BCS). ET is one of the most active CT regimens for metastatic breast cancer. The primary endpoint of this study was to evaluate clinical response Methods: Eligible patients (pts) were newly diagnosed with EBC and had large primary tumors (stage II-III, > 3 cm). Forty-seven pts were enrolled and received epirubicin 60 mg/m2 followed by docetaxel 60 mg/m2 every 3 weeks for 4 cycles before surgery. Within 4 weeks after surgery, 4 additional cycles of ET were given to the pts who responded to ET. Results: Forty-five pts were evaluable for safety and clinical response. The median age was 47 (range, 29–75). The tumor size was T2 in 44% of the pts, T3 in 36%, and T4 in 20%. ER and PgR were both positive in 40% of pts, while both negative in 31%. HER2 was positive in 33% of pts. Four cycles of ET at full dose were given to 96% of pts prior to surgery. The clinical response was 73% including 7% CR (95% CI 58–85%); the BCS rate was 36%. Central pathologic review was performed in 37 pts showing disappearance of all tumor cells (grade 1) in 1 patient (3%) and 2 pts (5%) achieved a grade 2 response (in situ carcinoma in the operated breast) by Chevallier’s criteria. Grade 3–4 toxicities included neutropenia (71%), leukocytopenia (69%), febrile neutropenia (18%) and anorexia (9%). Twenty-four of 33 pts who responded to ET received additional ET after surgery. Conclusions: ET showed a high clinical response in previously untreated EBC with acceptable toxicity. In order to improve pathological CRs further, the doses and treatment schedule of this regimen needs to be improved. Currently, we are following the pts to assess differences in survival between pts with or without additional adjuvant ET.

No significant financial relationships to disclose.

[Studies on quality and safety control of drugs for human use from transgenic animals/clone animals]

Recently the pharmaceuticals, which were produced using transgenic animals, have been developed, and will be submitted for registration in nearly future in Japan as well as in USA and EU. In addition, clone animals are also thought to be useful for the productions of the pharmaceuticals. This study has been, therefore, undertaken to establish the technical requirement for registration of the pharmaceuticals. They should be evaluated from the following standpoints: 1) Transgene construct and its characterization; 2) Creation and characterization of the transgenic founder animal; 3) Establishment of a reliable and continuous source of transgenic founder animals; 4) Generation and selection of the production animals; 5) Maintenance of transgenic animals; 6) Recovery and purification of products from transgenic animals; 7) Characterization of products; 8) Process validation/evaluation and in-process test; 9) Specification of products; 10) Stability of products; 11) Preclinical safety evaluation and clinical evaluation. Cloning technology by nuclear transfer of a transformed somatic cell has been already applied to the creation of the transgenic founder animal for the production of pharmaceuticals. The pharmaceuticals produced using the clone animals could be evaluated from almost the same standpoints. However, the flexible evaluation will be also needed depending on the development of the technology.

Deletion of 12 carboxyl-terminal residues from pig 3alpha/beta,20beta-hydroxysteroid dehydrogenase affects steroid metabolism

Pig 3alpha/beta,20beta-hydroxysteroid dehydrogenase (3alpha/beta,20beta-HSD) is 80-85% identical to human, rat, and mouse carbonyl reductases. However, pig 3alpha/beta,20beta-HSD contains an extra 12 amino acids at its COOH-terminus that these other mammalian carbonyl reductases lack. We constructed a pig 3alpha/beta,20beta-HSD mutant, G278opal, which lacks these amino acids and found that compared to wild-type 3alpha/beta,20beta-HSD, G278opal has a 10-fold lower catalytic efficiency for testosterone and progesterone. G278opal also has lower 3alpha- and 20beta-reductase and increased 3beta-reductase activity compared to wild-type 3alpha/beta,20beta-HSD. Binding of NADPH to G278opal was similar to that of wild-type 3alpha/beta,20beta-HSD. The recently determined three-dimensional structure of 3alpha/beta,20beta-HSD, without a steroid substrate, shows the 12 COOH-terminal amino acids in a random configuration. Our data indicate that the 12 COOH-terminal amino acids have a role in steroid metabolism suggesting that binding of steroid to wild-type 3alpha/beta,20beta-HSD induces a conformational change in which the 12 COOH-terminal amino acids interact with the steroid substrate.

Cobalamin deficiency results in severe metabolic disorder of serine and threonine in rats

Dietary cobalamin (vitamin B12; Cbl) deficiency caused significant increases in plasma serine, threonine, glycine, alanine, tyrosine, lysine and histidine levels in rats. In particular, the serine and threonine levels were over five and eight times, respectively, higher in the Cbl-deficient rats than those in the sufficient controls. In addition, some amino acids, including serine and threonine, were excreted into urine at significantly higher levels in the deficient rats. When Cbl was supplemented into the deficient rats for 2 weeks, in coincidence with the disappearance of the urinary excretion of methylmalonic acid (an index of Cbl deficiency), the plasma serine and threonine levels were normalized. These results indicate that Cbl deficiency results in metabolic disorder of certain amino acids, including serine and threonine. The expression level of hepatic serine dehydratase (SDH), which catalyzes the conversion of serine and threonine to pyruvate and 2-oxobutyrate, respectively, was significantly lowered by Cbl deficiency, even though Cbl does not participate directly in the enzyme reaction. The SDH activity in the deficient rats was less than 20% of that in the sufficient controls, and was normalized 2 weeks after the Cbl supplementation. It is thus suggested that the decrease of the SDH expression relates closely with the abnormalities in the plasma and urinary levels of serine and threonine in the Cbl-deficient rats.

A collision tumor composed of adenocarcinoma and malignant lymphoma in the remnant stomach after pancreatoduodenectomy: report of a case

The occurrence of a collision tumor in the stomach, consisting of adenocarcinoma and malignant lymphoma, is extremely rare. We report herein the case of a patient who had undergone a pancreatoduodenectomy for bile duct cancer 5 year earlier, in whom an ulcerating tumor of the remnant stomach developed and grew rapidly within 5 months. Surgical exploration revealed a tumor in the remnant stomach, multiple liver metastases, and multiple lymph node metastases. Total resection of the remnant stomach was performed, and pathological examination revealed a collision tumor consisting of adenocarcinoma and malignant lymphoma. The patient died of liver metastases and lymph node metastases 7 months after his second operation. The coexistence of both adenocarcinoma and malignant lymphoma of the remnant stomach and the etiology of this unusual combination, never previously reported, is discussed.

Immunohistochemical analysis on biological markers in ductal carcinoma in situ of the breast

BACKGROUND

The increasing use of mammographic screening has led to an increased detection of ductal carcinoma in situ (DCIS) of the breast. The detailed biological characteristics of DCIS and a new classification of DCIS based on these characteristics are needed.

METHODS

Immunohistochemical studies were performed to assess the expression of c-erbB-2 (ErbB-2), estrogen receptor (ER), p53 and proliferative activity (Ki-67) in 65 patients with pure DCIS and 60 with invasive ductal carcinoma (IDC). We classified pure DCIS tumors using three classifications, the architectural, Nottingham, and Van Nuys classifications.

RESULTS

ErbB-2, ER and p53 staining was positive in 34%, 66% and 21% of patients with DCIS, respectively, and 58%, 42% and 33% in patients with IDC, respectively. Ki-67 stained positively in 1.5% of patients with DCIS and 11.2% of patients with IDC. The comedo type showed a high rate of positive ErbB-2 and p53 staining. The cribriform and papillary types showed a high rate of positive ER staining. Under the Van Nuys classification, ErbB-2, p53 and Ki-67 expression were highest in the group with high nuclear grade and lowest in the group with non-high nuclear grade without necrosis.

CONCLUSION

Although the biological markers of IDC tended to suggest aggressive behavior more so than those of DCIS, these differences were based on the histological sub-type, comedo or non-comedo. The Van Nuys classification best defined the subgroups of DCIS with a distinct expression pattern of biological markers, and the best candidates for breast-conserving surgery.

Highly efficient deacetylation by use of the neutral organotin catalyst [tBu2SnOH(Cl)]2

Deprotection of acetyl esters is effected cleanly by the neutral organotin catalyst, [tBu2SnOH(Cl)]2. The mildness of the reaction gives rise to great synthetic versatility and in the process a variety of functional groups are tolerated. Differentiations between primary, secondary, and tertiary alcohols and between acetyl ester and other esters are feasible. No racemization occurs with chiral acetyl esters. Exclusive deprotection of primary acetyl esters in carbohydrates and nucleosides is observed. The crude product thus obtained can be used for further reactions without purification.

Pathological features of mucinous carcinoma of the breast are favourable for breast-conserving therapy

AIM

The effectiveness of breast-conserving therapy for mucinous carcinoma has not been well documented. We examined clinical and pathological features of cases to determine whether patients with mucinous carcinoma were suitable candidates for this treatment.

METHOD

Cases of pure type (n=52) and mixed type (n=24) mucinous carcinomas were reviewed with emphasis on the risk factors associated with local recurrences after breast-conserving therapy.

RESULTS

Large pure mucinous carcinomas had a low incidence of extensive intraductal spreading (EIS). An inverse correlation existed between the incidence of EIS and tumour size (P<0.05). Comedo type EIS was infrequent (11%) in pure mucinous carcinoma. Incidences of lymphatic vessel invasion (4%) and nodal involvement (4%) were lower in pure mucinous carcinoma than in mixed carcinoma (P<0.05). No nodal involvement occurred in patients with pure mucinous carcinoma less than 3 cm in diameter.

CONCLUSIONS

Patients with pure mucinous carcinomas, except those invading the local skin, are suitable candidates for breast-conserving therapy. Most pure mucinous carcinomas, including a large tumour up to 5 cm in diameter, can be treated with this therapy.

Possible physiological roles of proteolytic products of actin in neutrophils of patients with Behçet's disease

A truncated actin with an N-terminus of Met-44 is known to be selectively increased in neutrophils of patients with Behçet's disease and to be generated proteolytically by PMN-elastase (Yamashita S. et al., Biol. Pharm. Bull., 23, 519-522 (2000); Biol. Pharm. Bull., 24, 119-122 (2001)). In this study, the functions of the N-terminal peptide consisting of Asp-2 to Val-43 of beta-actin (42-merP) and the truncated actin with an N-terminus of Met-44 were examined. We first confirmed that the 42-merP existed in the patient plasma. The motility of human peripheral blood neutrophils and neutrophilic granulocytes differentiated from HL-60 cells was suppressed by the 42-merP. Furthermore, when neutrophil-like cells from HL-60 cells were preincubated with 10 nm 42-merP, migration of the cells induced by chemotactic factors such as fMLP and IL-8 was suppressed. The release of PMN-elastase, which is a neutrophil granular enzyme that is responsible for the production of the 42-merP and truncated actin, was suppressed by pretreating the neutrophils with 42-merP before fMLP-stimulation. The truncated actin was unable to polymerize in 0.1 M KCl, suggesting that the increase of truncated actin damages the reconstitution capacity of actin in neutrophils of the patients. These results suggest that the increase of 42-merP and truncated actin in patients with Behçet's disease changes functions of neutrophils

[Effect of gallic acid derivatives on secretion of Th1 cytokines and Th2 cytokines from anti CD3-stimulated spleen cells]

As reported previously (Kosuge et al., Yakugaku Zasshi, 120, 408 (2000)), methyl gallate, a gallic acid derivative, which has been one of compounds isolated from extracts of Psidium geneus Myrtaceae, selectively suppresses Th2 cytokine secretion. In the present study, to examine more effective compounds than methyl gallate, the effects of various gallic acid derivatives on the secretion of helper T cell subtype specific cytokines from anti CD3-stimulated spleen cells were investigated. Ten micrograms/ml of methyl gallate and ethyl gallate remarkably suppressed the secretion of IL-4 and IL-5, Th2 cytokines, but did not suppress meaningfully the secretion of IFN-gamma, a Th1 cytokine. On the other hand, the other gallic acid derivatives suppressed the secretion of both IL-4 and IFN-gamma. Ten micrograms/ml of methyl gallate suppressed the secretion of IL-2, a Th1 cytokine, but the same concentration of ethyl gallate did not suppress it. In conclusion, it seemed that ethyl gallate was the most selective inhibitor for the secretion of Th2 cytokines among gallic acid derivatives used in this study.

Tubular carcinoma of the breast: a histologic subtype indicative of breast-conserving therapy

We reviewed the clinical and pathologic features of pure tubular carcinoma of the breast with particular emphasis on the reported risk factors associated with local recurrences and survival following breast-conserving therapy. Of 1653 cases of invasive breast cancer, 12 (0.7%) were identified as pure tubular carcinoma. Clinical/pathologic features of pure tubular carcinoma were compared with those of T1 invasive carcinoma of all other histologic types (T1 IC). Of the 12 patients with pure tubular carcinoma (median tumor diameter 1.4 cm; range 0.5-3.0 cm), a multicentric association was identified in one patient while a multifocal association was seen in two. One patient had nodal metastatic disease out of the ten who underwent axillary dissection. No lymphatic vessel invasion was identified in any tumors (P < 0.1 vs T1 IC). In addition, extensive intraductal spread was not present in any tumors (P < 0.05 vs T1 IC). This study shows that patients with pure tubular carcinoma are appropriate candidates for breast-conserving therapy based on the clinical/ pathologic features. When a multifocal association is suspected preoperatively, either a wide local excision or a quadrantectomy which includes other lesions is thus recommended.

Characterization of a protease responsible for truncated actin increase in neutrophils of patients with Behçet's disease

As described previously (Yamashita S. et al., Biol. Pharm. Bull., 23, 519-522 (2000)), high levels of a truncated actin with an N-terminus of Met-44 were detected in neutrophils of patients with Behcet's disease. Since the increase of the truncated actin in neutrophils of patients may be important for understanding the pathology of Behçet's disease, the mechanism of the truncated actin formation was studied. First, to investigate the presence of a specific protease, which cleaves the actin at the site between Val-43 and Met-44, a peptide with a partial amino acid sequence of actin from the N-terminal Pro-38 to Asp-51 was synthesized as the protease substrate. The synthesized peptide was digested with cytosolic fractions of neutrophils from patients and healthy volunteers, and digestion products were analyzed by C18-reverse phase HPLC. The chromatograms of these samples showed that an endoprotease, which cleaved the peptide at a specific site, was present in cytosolic fractions of neutrophils from patients with Behçet's disease. Then, the effects of various kinds of protease inhibitors on the digestion of the peptide were investigated in order to identify the responsible endoprotease. The digestion of the peptide was suppressed by 4-(2-aminoethyl) benzenesulfonylfluoride (AEBSF, a serine protease inhibitor) and N-methoxysuccinyl-Ala-Ala-Pro-Val chloromethylketone (CMK, a polymorphonuclear (PMN)-elastase inhibitor) in the presence of EDTA. Furthermore, PMN-elastase was found to cleave the substrate peptide and actin at the site between Val-43 and Met-44. These results lead to the conclusion that the PMN-elastase is responsible for cleavage of actin at the N-terminal site between Val-43 and Met-44 in neutrophils from patients with Behçet's disease.

Thyroid metastasis from hepatocellular carcinoma as an initial presentation: a case report

Although metastases to the thyroid are not uncommon at autopsy, most of these lesions are clinically occult. To our knowledge, this is the first report of a case of hepatocellular carcinoma initially presenting as a thyroid mass. Various radiological studies suggested malignant thyroid tumor, and core needle biopsy was performed. Metastasis from hepatocellular carcinoma was histopathologically suspected, and subsequent abdominal CT revealed advanced hepatocellular carcinoma.

Biochemical identification of the neutral endopeptidase family member responsible for the catabolism of amyloid beta peptide in the brain

Amyloid beta peptide (Abeta) is a physiological peptide that is constantly catabolized in the brain. We previously demonstrated that an endopeptidase sensitive to phosphoramidon and thiorphan conducts the initial rate-limiting proteolysis of Abeta in vivo, but the exact molecular identity of the peptidase(s) has remained unknown because of the molecular redundancy of such activity. We analyzed the brain-derived enzyme by means of immuno-depletion and gene disruption, and demonstrate here that neprilysin accounts for the majority of the Abeta-degrading activity. Furthermore, kinetic analysis, giving a K(m) value of 2.8 +/- 0.76 microM, indicated that Abeta(1-42) is a relevant substrate for neprilysin.

Rhabdoid features in leiomyosarcoma of soft tissue: with special reference to aggressive behavior

The presence of rhabdoid cells has been reported in various types of malignant neoplasms and has been determined to be a predictor of aggressive behavior of neoplasms regardless of tumor histogenesis. One hundred and thirteen cases of leiomyosarcoma, selected from 1800 soft tissue sarcomas, were reviewed on hematoxylin and eosin sections, and immunohistochemical staining when available, and seven cases with rhabdoid features were retrieved. Clinicopathologic differences were analyzed to compare between cases with rhabdoid features and those without rhabdoid features. In the seven cases with rhabdoid features, two were intra-abdominal, and the others arose in external soft tissues including muscle, subcutis, and cutis. Patient age ranged from 33 to 84 years, three were female, and four were male. Tumor size ranged from 3 to 22 cm. Clinical evidence showed no differences from those cases without rhabdoid features. Histologically, one of the abdominal cases was epithelioid leiomyosarcoma. Two of the 7 cases were better subclassified as pleomorphic leiomyosarcoma, in which rhabdoid cells are diffusely scattered. In cases other than those with pleomorphic leiomyosarcomas, foci of anaplastic areas were observed, and collections of rhabdoid cells were present in those areas. Immunohistochemical examination of the cases confirmed myogenic differentiation, and showed rhabdoid cells being positive for vimentin and desmin in the inclusion bodies, and diffusely so for muscle actin in the cytoplasm. After dividing all the cases of leiomyosarcoma by their location, prognostic analysis was performed. Leiomyosarcoma of external soft tissue with rhabdoid cells showed a tendency for poorer prognoses than cases without rhabdoid features. On the contrary, retroperitoneal cases did not. This study indicates that rhabdoid features are associated with aggressive biological behavior in leiomyosarcoma of the external soft tissue.

Functional evaluation of hydronephrosis by diffusion-weighted MR imaging. Relationship between apparent diffusion coefficient and split glomerular filtration rate

PURPOSE

To determine the relationship between apparent diffusion coefficient (ADC) values measured by diffusion-weighted MR imaging and split renal function determined by renal scintigraphy in patients with hydronephrosis.

MATERIAL AND METHODS

Diffusion-weighted imaging on a 1.5 T MR unit and renal scintigraphy were performed in 36 patients with hydronephrosis (45 hydronephrotic kidneys, 21 non-hydronephrotic kidneys). ADC values of the individual kidneys were measured by diffusion-weighted MR imaging. Split renal function (glomerular filtration rate (GFR)) was determined by renal scintigraphy using 99mTc-DTPA. The relationship between ADC values and split GFR was examined in 66 kidneys. The hydronephrotic kidneys were further classified into three groups (severe renal dysfunction, GFR <10 ml/min, n=7; moderate renal dysfunction, GFR 10-25 ml/min, n= 10; normal renal function, GFR >25 ml/ min, n=28), and mean values for ADCs were calculated.

RESULTS

In hydronephrotic kidneys, there was a moderate positive correlation between ADC values and split GFR (R2=0.56). On the other hand, in nonhydronephrotic kidneys, poor correlation between ADC values and split GFR was observed (R2=0.08). The mean values for ADCs of the dysfunctioning hydronephrotic kidneys (severe renal dysfunction, 1.32 x 10(-3) +/- 0.18 x 10(-3) mm2/s; moderate renal dysfunction, 1.38 x 10(-3) +/- 0.10 x 10(-3) mm2/s) were significantly lower than that of the normal functioning hydronephrotic kidneys (1.63 x 10(-3) +/- 0.12 +/- 10(-3) mm2/s).

CONCLUSION

These results indicated that measurement of ADC values by diffusion-weighted MR imaging has a potential value in the evaluation of the functional status of hydronephrotic kidneys.

Loss of heterozygosity and microsatellite instability in ductal carcinoma in situ of the breast

To investigate the alterations of genetic instabilities in carcinogenesis of the breast, we analyzed the allelotypic profile of 65 ductal carcinomas in situ (DCIS), compared with that of 207 invasive ductal carcinomas (IDC) of the breast. These studies were performed by means of examining microsatellite-length polymorphisms at seven loci (AluVpa, ESR, D11S988, D13S267, D16S398, D17S1159, and D17S855) from microdissected paraffin sections. Allelic loss or imbalance, considered a loss of heterozygosity (LOH), tended to be more frequently seen in IDC than in DCIS. In particular, the frequency of LOH at the 17p locus was significantly higher in IDC than in DCIS (42 vs. 23%, P=0.022). LOH in DCIS was most frequently seen at D16S398 (26%). LOH frequency at D16S398 in low- and intermediate-grade DCIS was higher than that in high-grade DCIS, while LOH frequencies at D11S988 and D17S1159 in low- and intermediate-grade DCIS was lower than those in high-grade DCIS. LOH frequency at D11S988 in non-comedo type DCIS was lower than that in comedo type DCIS. Furthermore, the frequency of microsatellite instability (MSI) at only one locus in DCIS (28%) was statistically higher than that in IDC (6%) (P<0.001), while there was no difference between the frequency of MSI at multiple loci in DCIS (6%) and that in IDC (3%). Together, these observations indicate that chromosomal losses of 16q may occur in low- and intermediate-grade DCIS and those of 11p and 17p may occur high-grade DCIS, and that MSI occurring at only one locus is not yet clear and MSI at multiple loci is uncommon in not only IDC but also DCIS of the breast.

Activating Gs(alpha) mutation in intramuscular myxomas with and without fibrous dysplasia of bone

Activating missense mutations in the Arg 201 codon of the gene encoding the alpha subunit of Gs, the G protein that stimulates cAMP formation, have been recognized as the cause of many endocrine diseases, McCune-Albright syndrome and isolated fibrous dysplasia of bone. On the other hand, intramuscular myxomas with fibrous dysplasia, so-called Mazabraud's syndrome, have been sporadically reported, but it has not been confirmed whether intramuscular myxoma, with or without fibrous dysplasia, is associated with the Gs(alpha) mutations. We investigated the presence of the Gs(alpha) mutations in intramuscular myxomas with or without fibrous dysplasia by a PCR-SSCP assay, using formalin-fixed, paraffin-embedded tissues. In five of the six intramuscular myxomas (three with and two without fibrous dysplasia), point mutations were detected as aberrant bands by SSCP, which were confirmed by a subsequent sequence analysis (three Arg to His and two Arg to Cys). This result suggests that the Gs(alpha) mutations are related to tumorigenesis in intramuscular myxoma and that intramuscular myxoma is one of the diseases induced by abnormal Gs(alpha) protein.

Axillary lymph node metastases in patients with small carcinomas of the breast: is accurate prediction possible?

OBJECTIVES

To find out whether macroscopic classification of the tumour margin is predictive of axillary lymph node metastases and to identify a combination of clinical and pathological findings by which axillary node status can be predicted accurately in small carcinomas (T1) of the breast.

DESIGN

Retrospective study.

SETTING

Municipal referral centre, Japan.

SUBJECTS

All 1003 patients with T1 invasive carcinoma of the breast who had axillary lymph node dissection between January 1970 and December 1996 as part of their treatment.

MAIN OUTCOME MEASURES

The association between the incidence of axillary lymph node metastases and 10 clinical and pathological factors (age, palpability and size of tumour, macroscopic classification of tumour margin, clinical axillary status, radiating spiculation on a mammogram, histological type, lymphatic invasion, oestrogen and progesterone receptor status) were analysed.

RESULTS

Clinical axillary node status, macroscopic classification of tumour margin, lymphatic invasion, and age of the patient were significant predictors of axillary lymph node metastases (p < 0.01 in each case). Among 47 patients aged 65 or more whose tumours had well-defined margins and with a clinical N0 status in the axillae, the incidence of histological axillary lymph node metastasis was only 6% (n = 3) whereas it was 65% in 57 patients with tumours of ill-defined margins whose axillae were N1 or N2.

CONCLUSIONS

Macroscopic classification of tumour margins is an independent predictor of axillary lymph node metastases for patients with small carcinomas of the breast. However, even with combinations of the examined predictors of axillary node metastases, the subgroup of patients at minimal risk of metastasis was less than 5% in T1 breast cancer, whereas three-quarters of the patients had clear axillary lymph nodes. Most patients with T1 breast cancer will need surgical staging of the axillae by methods such as sentinel node biopsy.

[Activities of antimicrobial agents against 5,180 clinical isolates obtained from 26 medical institutions during 1998 in Japan. Levofloxacin--Surveillance Group]

The surveillance study was conducted to determine the antimicrobial activity of fluoroquinolones (ofloxacin, levofloxacin, ciprofloxacin, tosufloxacin) and other 20 antimicrobial agents against 5,180 clinical isolates obtained from 26 medical institutions during 1998 in Japan. The resistance to fluoroquinolones was remarkable in Enterococci, methicillin-resistant staphylococci and Pseudomonas aeruginosa from UTI. However, many of the common pathogens such as Streptococcus pneumoniae including penicillin-resistant isolates, methicillin-susceptible Stahylococcus aureus, Moraxella catarrhalis, the family of Enterobacteriaceae, Haemophilus influenzae including ampicillin-resistant isolates have been kept to be susceptible to fluoroquinolones. About 90% of P. aeruginosa isolates from RTI were susceptible to fluoroquinolones. In conclusion, the results from this surveillance study suggest that fluoroquinolones are useful in the treatment of various bacterial infections including respiratory infections.

Comparison of fluid-attenuated inversion-recovery MR imaging with CT in a simulated model of acute subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Because MR imaging is becoming integral to the evaluation and treatment of very early stroke, it is critical to prove that MR imaging is at least as sensitive to acute subarachnoid hemorrhage (SAH) as is CT. The present study was conducted to evaluate the possibility of detecting a small amount of acute SAH diluted by CSF not revealed by CT but identified on fluid-attenuated inversion-recovery (FLAIR) MR images in an in vitro study.

METHODS

Acute SAH was simulated with mixtures of artificial CSF and arterial blood (hematocrit [Hct], 45%) ranging from 0% to 100% by volume. We scanned these phantoms with CT and turbo-FLAIR MR imaging (9000/119 [TR/effective TE]; inversion time, 2200 ms; echo train length, 7), and we measured T1 and T2 relaxation times of these phantoms at temperatures within 36 degrees C to 37 degrees C. Plots of CT value from the different blood/water mixture ratios versus Hct were generated and correlated with the average CT value from normal cortex. We measured T1 and T2 relaxation times of these phantoms and normal cortex and generated T2 relaxation curves as a function of effective TE for a specific inversion time (2200), and determined the TR (9000) for the turbo-FLAIR sequence by using a theoretical equation for the turbo inversion recovery signal intensity.

RESULTS

Above a Hct of 27% blood, the mixture was denser on CT scans than was the normal cortex. At a selected time longer than an effective TE of 120, above a Hct of 22.4% blood, the mixture was more hyperintense than the normal cortex on turbo-FLAIR images. At selected times longer than an effective TE of 160, above a Hct of 9% blood, the mixture was more hyperintense than was the normal cortex.

CONCLUSION

FLAIR imaging is more sensitive than CT in the detection of a small amount of acute SAH diluted by CSF at selected appropriate TE, as determined in an in vitro study.

Analysis of neutrophil proteins of patients with Behçet's disease by two-dimensional gel electrophoresis

Protein changes in the neutrophils of patients with Behçet's disease were analyzed by high resolution two-dimensional gel electrophoresis to investigate the pathological features of Behçet's disease. Two clear protein spots were found to be differently expressed between healthy volunteers and patients with Behçet's disease. One was a 53 kDa protein with pI 5.2 that was detected in healthy volunteers but was nearly absent in the patients. The other was a 40 kDa protein with pI 5.2 that was detected in the patients but nearly absent in the healthy volunteers. Analysis of the N-terminal amino acid sequence of the 40 kDa protein revealed that it was a truncated actin with an N-terminus of Met-44. The presence of the truncated actin in the neutrophils of patients was confirmed by Western blot analysis using an antibody to the C-terminus of actin. The 53 kDa protein could not be identified because its N-terminus was blocked. The presence of the truncated actin in the neutrophils of the patients may be important in understanding the pathology of Behçet's disease.

Increased degradation of newly synthesized interferon-gamma (IFN-gamma) in anti CD3-stimulated lymphocytes treated with glycoprotein processing inhibitors

As described previously (Kosuge T., Toyoshima S., Biol. Pharm. Bull., 23, 1-5 (2000)), inhibitors of the glycoprotein processing enzymes, glucosidase I and II, induce decreased secretion of interferon-gamma (IFN-gamma) into culture supernatants of anti CD3-stimulated lymphocytes, and in the present study the mechanism has been investigated in further detail. The processing inhibitors did not affect intracellular levels of IFN-gamma but enhanced the degradation of newly synthesized IFN-gamma in anti CD3-stimulated lymphocytes. Furthermore, since the stability of N-glycosylated proteins is known to be regulated by lectin family chaperones, such as calnexin, a type I transmembrane protein located in the endoplasmic reticulum (ER), and calreticulin, a soluble protein in the ER lumen, the effect of the processing inhibitors on the interaction of IFN-gamma with calnexin and calreticulin was investigated. It was found that IFN-gamma formed complexes with calnexin and calreticulin in anti CD3-stimulated lymphocytes. Total binding of IFN-gamma to calnexin was not affected but that to calreticulin was increased in anti CD3-stimulated lymphocytes treated with the processing inhibitors. However, binding of newly synthesized IFN-gamma to calreticulin was decreased in the lymphocytes under the same conditions as above. These results suggest that these glycoprotein processing inhibitors block the release of IFN-gamma from already formed calreticulin complexes, which prevents the binding of newly synthesized IFN-gamma to calreticulin and results in the enhancement of IFN-gamma degradation.

[Effects of psidium components on cytokine productions in helper T cells and type-I allergy]

Psidium genus Myrtaceae (Psidium) is known to be a chinese medicine with an anti-allergy effect. In the present study, to identify active components in Psidium and investigate mechanisms of its anti-allergy effect, effects of several components isolated from Psidium on cytokine production in helper T cell subtypes, Th1 and Th2 cells, were studied. All components, except methyl gallate, suppressed cytokine production in both Th1 and Th2 cells. Then, effects of methyl gallate on IgE production in a model mouse with type I allergy were studied. Methyl gallate suppressed IgE production in the mouse. Only methyl gallate selectively suppressed Th2-cytokine production.

Effect of inhibitors of glycoprotein processing on cytokine secretion and production in anti CD3-stimulated T cells

We have investigated the effect of inhibitors of glycoprotein processing on cytokine secretion and production in anti CD3-stimulated T cells to elucidate the role of carbohydrate in the triggering of T cell function. The inhibitors of glycoprotein processing, especially mannnosidase inhibitors, enhanced the anti CD3-induced production of interleukin-2 (IL-2), which is a cytokine without the linkage sequence of N-linked oligosaccharides. On the other hand, N-methyl-1-deoxynojirimycin (NMdNM, an inhibitor of processing glucosidase 1), 1-deoxynojirimycin (dNM, an inhibitor of processing glucosidase I and II) and bromoconduritol (BCD, an inhibitor of processing glucosidase II) inhibited the secretion of interleukin-4 (IL-4), interferon-gamma (IFN-gamma), or interleukin-5 (IL-5) into culture supernatants of anti CD3-stimulated T cells, which had N-linked oligosaccharides. Mannosidase inhibitors, 1-deoxymannojirimycin (dMAN, an inhibitor of processing mannosidase I) and swainsonine (SWN, an inhibitor of processing mannosidase II) did not inhibit the secretion or production of IL-4, IFN-gamma and IL-5. To confirm the inhibition of N-linked oligosaccharide processing in the cytokines by the above inhibitors, the binding of IFN-gamma to lectins with various sugar-binding specificities was investigated. All inhibitors reduced the binding of IFN-gamma to PHA E4, which had a high affinity to bi- or tri-antennary complex type N-linked oligosaccharides with bisecting N-acetylglucosamine. Similarly, all inhibitors reduced the binding of IFN-gamma to PHA L4, which had high affinity to tri- or tetra-antennary complex type N-linked oligosaccharides with beta1-6-linked branching. SWN and dMAN increased the binding of IFN-gamma to concanavalin A (ConA), which had a high affinity to bi-antennary complex type, hybrid type and high-mannose type N-linked oligosaccharides. These results suggest that the processing inhibitors used here inhibit the N-linked oligosaccharide processing of cytokines, and the inhibition of processing enzyme glucosidases I and II induces a decreased secretion of cytokines with N4-linked oligosaccharides.

Process of egg formation in the female body cavity and fertilization in male eggs of Phytoseiulus persimilis (Acari: Phytoseiidae)

The process of egg formation in the body cavity of a phytoseiid mite, Phytoseiulus persimilis, was observed to examine fertilization of male eggs. After insemination, one of the ova at the periphery of the ovary began to expand, taking up yolk. Two pronuclei appeared in the expanded egg, located dorsally in the ovary, and yolk granules were formed gradually. After the egg became filled with yolk granules the two pronuclei fused. The egg moved via the narrow entrance at the ventral region into the oviduct, where the eggshell was formed. When the eggshell was complete, and while embryogenesis proceeded, the egg was deposited. In the meantime some ova began to expand sequentially and two joining pronuclei appeared in expanding eggs. The joining pronuclei in the first egg proved male diploidy. This is additional evidence of pseudo-arrhenotoky in this phytoseiid mite species, since the first eggs developed into males.

Mediastinal parathyroid cyst: treatment with thoracoscopic surgery--a case report

Parathyroid cysts are rarely located in the mediastinum. This report describes a 45-year-old man with a mediastinal parathyroid cyst. Video-assisted thoracic surgery was successfully performed to remove the cyst.

Acetylleucine chloromethyl ketone, an inhibitor of acylpeptide hydrolase, induces apoptosis of U937 cells

Acetylleucine chloromethyl ketone (ALCK), an inhibitor of acylpeptide hydrolase (ACPH), inhibited the growth of human monoblastic U937 cells in a dose- and time-dependent manner. Morphology of the ALCK-exposed cells showed typical apoptosis, judging from the nuclear condensation and segmentation. Chromosomal DNA of U937 cells treated with ALCK showed an internucleosomal ladder-like pattern on electrophoresis, being characteristic of apoptosis. Of the other leucine chloromethyl ketone analogues, butyloylleucine chloromethyl ketone (BLCK) induced a weak ladder-like formation but caploylleucine chloromethyl ketone (CLCK)barely did. On the other hand, intracellular ACPH activity of U937 cells was strongly inhibited by culturing with ALCK, moderately with BLCK, and not with CLCK. These findings indicate that the inhibition of ACPH activity leads to apoptosis and suggest that ACPH may play a vital role in eukaryotic cells.

Transient association of the nicotinamide adenine dinucleotide phosphate oxidase subunits p47phox and p67phox with phagosomes in neutrophils from patients with X-linked chronic granulomatous disease

Optimal microbicidal activity of polymorphonuclear leukocytes (PMNs) requires recruitment of a functional nicotinamide adenine dinucleotide phosphate (NADPH) oxidase to the phagosome. In this study, we used a synchronized phagocytosis assay and immunofluorescence microscopy (IFM) to examine the association of cytosolic NADPH oxidase subunits with phagosomes containing opsonized zymosan (OpZ). Ingestion of OpZ began within 30 seconds of particle binding and forming phagosomes were enriched for both F-actin and the actin-binding protein p57. NADPH oxidase subunits p47phox and p67phox were also recruited to forming phagosomes and were retained on mature phagosomes for at least 15 minutes. Colocalization of F-actin, p57, and p47phox on phagosomes was confirmed by immunoblotting. Translocation of p67phox, but not p57, to forming phagosomes was deficient in PMNs lacking p47phox. Surprisingly, we found that in PMNs from six individuals with X-linked chronic granulomatous disease (CGD), p47phox and p67phox accumulated in the periphagosomal area during ingestion of OpZ. However, in marked contrast to normal PMNs, p47phox and p67phox were shed from nascent phagosomes along with F-actin and p57 once OpZ was internalized (approximately 5 minutes). These data support a model in which flavocytochrome b is required for stable membrane binding of p47phox and p67phox, but not their association with the cytoskeleton or transport to the cell periphery.

Apoptosis and cell proliferation in medullary carcinoma of the breast: a comparative study between medullary and non-medullary carcinoma using the TUNEL method and immunohistochemistry

BACKGROUND AND OBJECTIVES

Medullary carcinoma of the breast has generally been considered to result in better prognosis than ordinary invasive ductal carcinoma, which would seem to be discrepant when one considers its anaplastic histology and high mitotic rate. We attempted to elucidate the prognostic implications of apoptosis and cell proliferation in medullary carcinoma of the breast.

METHODS

Formalin-fixed, paraffin-embedded specimens of 50 cases of typical medullary carcinoma (MC) of the breast and those of 50 control cases of non-medullary invasive ductal carcinoma (N-MC), which were matched to the MC cases in both age and TNM classification, were investigated utilizing the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method and immunohistochemistry for p53, bcl-2, and Ki-67.

RESULTS

Mean values of the apoptotic index (AI), the proliferative index (PI), and the ratio of AI to PI (AI/PI) were significantly higher in MC than in N-MC (P < 0.0001). MC exhibited significantly lower positivity for bcl-2 than N-MC (P = 0.00003), while there was no significant difference in p53 positivity between MC and N-MC.

CONCLUSIONS

A high frequency of apoptosis may be related to a favorable prognosis in MC, even though it demonstrates a high proliferative activity, exhibiting a rapid cell turnover.

Role of diffusion-weighted echo-planar MRI in distinguishing between brain brain abscess and tumour: a preliminary report

Our purpose was to evaluate diffusion-weighted (DW) echo-planar MRI in differentiating between brain abscess and tumour. We examined two patients with surgically confirmed pyogenic brain abscess and 18 with metastatic brain tumours or high-grade glioma, using a 1.5 T system. The apparent diffusion coefficient (ADC) of each necrotic or solid contrast-enhancing lesion was measured with two different b values (20 and 1200 s/mm2). All capsule-stage brain abscesses (4 lesions) and zones of cerebritis (2 lesions) were identified on high-b-value DWI as markedly high-signal areas of decreased ADC (range, 0.58-0.70 [(10-3 mm2/s; mean, 0.63)]). All cystic or necrotic portions of brain tumours (14 lesions) were identified on high-b-value DWI as low-signal areas of increased ADC (range, 2.20-3.20 [(10-3 mm2/s; mean, 2.70)]). Solid, contrast-enhancing portions of brain tumours (19 lesions) were identified on high-b-value DWI as high-signal areas of sightly decreased or increased ADC (range, 0.77-1.29 [(10-3 mm2/s; mean, 0.94)]). Our preliminary results indicate that DW echo-planar MRI be used for distinguishing between brain abscess and tumour.

Characteristics of nitrogen metabolism in rats with thioacetamide-induced liver cirrhosis

Female Sprague-Dawley rats were given 0.03% thioacetamide (TAA) in their drinking water daily for 4 or 12 weeks, and were then given normal water for 4 weeks after the end of a 12-week TAA treatment to investigate amino acid metabolism. In the malnourished precirrhotic stage (stage 1) and the malnourished cirrhotic stage (stage 2), the aromatic amino acids (AAA), Glu, Asp, Orn, Arg and Cit increased, and the branched-chain amino acids (BCAA) decreased slightly. Because these changes normalized in the well-nourished cirrhotic stage (stage 3), they might have resulted from impairment of hepatocytes and malnutrition. The net uptake of BCAA into the liver increased in stage 2, but the AAA uptake did not exceed that in normal controls. Portal venous plasma AAA increased to the same level as arterial plasma AAA. These results suggest that the decrease in BCAA was partially due to liver uptake and that the increase in AAA was induced by reduction of liver uptake and overproduction in extrahepatic tissues. The liver contents of BCAA and AAA were unchanged in all stages, so were fully utilized in the impaired liver. The increases in Glu, Asp, Orn and Cit might have resulted from overproduction in the liver, because these contents of the liver increased in stage 2. In conclusion, the changes in amino acid metabolism in rats with cirrhosis induced by TAA closely resemble those seen in human liver cirrhosis.