[Leg pain under spinal anesthesia in leprosy patients]

We studied leg pain experienced under spinal anesthesia in leprosy patients. Seven of twenty patients complained of the leg pain a few minutes after spinal block. The pain was localized in the parts of deafferentation or phantom limb, and was relatively mild and controllable. We consider that the inhibitory system is inactivated when the somatic impulse is blocked by spinal anesthesia, and as a result the abnormal burst activity of dorsal horn produced by peripheral nerve damage of leprosy causes phantom pain.

Carbon-11 labeled ethionine and propionine as tumor detecting agents

To develop 18F-fluoroalkyl derivatives of methionine (MET) as a tumor detecting agent by mean of clinical PET, a pilot study assessing the potential of their parent compounds, 11C-labeled ethionine (11C-ETH) and propionine (11C-PRO), was performed. 11C-ETH and 11C-PRO were prepared by the reaction of L-homocysteine thiolactone and corresponding 11C-alkyl iodides. After i.v. injection of a mixture of 3H-MET. 14C-ETH and 11C-PRO into mice bearing FM3A mammary carcinoma, the highest FM3A uptake was found in 14C-ETH, followed by 3H-MET and 11C-PRO, while the FM3A-to-brain and FM3A-to-muscle ratios were nearly the same for all three compounds. The FM3A uptake of 14C-ETH and 11C-PRO were nearly equal or slightly higher than the liver uptake. In the pancreas, liver, FM3A and brain tissues, incorporation of 14C-ETH into acid-precipitable materials was much lower than that of 3H-MET, whereas no incorporation of 11C-PRO was found. Brain uptake of all three compounds was significantly reduced by carrier MET-loading (5 min p.i.) or by cycloheximide treatment to inhibit protein synthesis (60 min p.i.), whereas the FM3A uptake was not affected. Incorporation of 14C-ETH into acid-precipitable materials was inhibited by the cycloheximide. The results suggest that 11C-labeled ETH has a similar potential for tumor detection by PET as 11C-MET, and that 11C-PRO has similar properties to those of other artificial amino acids. The development of 18F-fluoroalkyl derivatives of MET is of interest as the next step.

Differences in spatial localization and chromatin pattern during different phases of cell cycle between normal and cancer cells

We studied differences in chromatin patterns and the spatial localization of centromeres of chromosome 11 during the cell cycle between normal peripheral blood lymphocytes (PBL) and human promyelocytic leukemia cells (HL-60) using fluorescence in situ hybridization. The pericentromeres in both cells were located at the periphery during Gq (quiescent) phase, but moved towards the nuclear center in G1 and mid-S phase. During G2, the pericentromeres of PBL continued to move towards the nuclear center whereas those of HL-60 returned to the periphery. The angle defining the spatial location of two pericentromeres, in reference to the center of the nucleus, increased in PBL cells from a mean of 67 degrees during Gq phase to 106 degrees during G1 phase (P < 0.01), and the two pericentromeres remained wide apart throughout the entire cell cycle. In HL-60, the angle also increased during G1, but then decreased during mid-S and G2 phases. Both cells exhibited pericentromeric signals during Gq that were round and compact, and the entire chromatin was loosely condensed. The signal became more loose and dispersed during the G1 and mid-S phases. The pericentromere signal varied during G2 and was generally rod-like or bipartite with condensation of the entire chromatin or chromosome-like. Our results suggest that subtle but important differences in spatial localization of pericentromeres are present during the interphase between normal PBL and HL-60 cells.

Thallium-201 single-photon emission tomography in the treatment follow-up of nasopharyngeal carcinoma

In order to assess the usefulness of thallium-201 single-photon emission tomography (SPET) in the treatment follow-up of nasopharyngeal carcinoma (NPC), a total of 75 201T1 SPET studies were performed in 18 patients with histologically proven NPC. The findings were compared with those of magnetic resonance imaging (MRI) before and after therapy. Four patients received radiotherapy alone while the other 14 received concurrent chemo-radiotherapy. Treatment response was classified as complete (CR) or partial (PR) based on the findings of MRI and 201T1 SPET. Intense 201T1 uptake by the tumour was seen in all 18 patients before treatment. After treatment, MRI showed seven CRs and 11 PRs, whereas 201T1 SPET showed 13 CRs and five PRs. In 12 patients, the results of 201T1 SPET were in agreement with those of MRI. In six patients MRI showed PR but 201T1 showed CR. Follow-up (mean 10.6 months) MRI and 201T1 SPET studies of these six patients revealed that tumour gradually decreased and finally vanished in three patients. This preliminary study indicates that 201T1 SPET has potential in the assessment of early response to treatment of patients with NPC when compared with MRI.

A rapid increase in the level of binding protein (BiP) is accompanied by synthesis and degradation of storage proteins in pumpkin cotyledons

The binding protein (BiP) has been implicated in cotranslational folding of nascent polypeptides, and in the recognition and disposal of aberrant polypeptides. To elucidate the involvement of BiP in the biosynthesis of vacuolar proteins, we have characterized the protein in pumpkin cotyledons during seed maturation and seedling growth. Isolated microsomes from maturing pumpkin cotyledons contained a significant amount of BiP, protein-disulfide isomerase and calreticulin. We have purified a 70-kDa protein; sequences of the N-terminus and internal fragments of this protein exhibited a high identity to the sequence of soybean. Immunoblot analysis with specific antibodies raised against the purified BiP showed that the amount of BiP in a cotyledon increased markedly at the middle stages and then decreased. The increase was accompanied by the synthesis of storage proteins and the development of the endoplasmic reticulum in the cotyledons at the middle stage of seed maturation. Most of these storage proteins degraded dramatically between 2 and 5 days after seed germination, and the degradation was also accompanied by a rapid increase in the level of BiP. Subcellular fractionation of the 4-day-old cotyledons showed a high accumulation of BiP in the endoplasmic reticulum. It is possible that BiP might be involved in the synthesis of seed storage proteins during maturation and in the synthesis of hydrolytic enzymes responsible for the degradation of the storage proteins during seed germination.

A new genus of the order Actinomycetales, Spirilliplanes gen. nov., with description of Spirilliplanes yamanashiensis sp. nov

Actinomycete strain YU127-1T (T = type strain), which produces zoospores, was isolated from a soil sample. The aerial mycelium of this organism at maturity forms short chains of spores. The hyphae form coils, and sporangia are not observed. Strain YU127-1T contains glutamic acid, glucosamine, glycine, alanine, and meso-diaminopimelic acid in its cell wall (wall chemotype II), 3-O-methylmannose, mannose, xylose, and glucose as whole-cell sugars, meanaquinone 10(H4), and glycolyl cell wall polysaccharides and has a guanine-plus-cytosine content of 69.0 mol%. Mycolic acids are absent. Phosphatidylinositol and phosphatidylethanolamine are diagnostic phospholipids. The chemotaxonomic data, except for the lack of arabinose in the whole-cell sugars, indicate that this strain belongs to the family Micromonosporaceae. The morphological and physiological characteristics and chemotaxonomic and phylogenetic data for this strain differ from those of the previously described actinomycetes. We therefore propose a new genus, spirilliplanes, for this organism; the type species of the genus is Spirilliplanes yamanashiensis sp. nov., and the type strain of S. yamanashiensis is strain YU127-1 (= IFO 15828).

Analysis of catalytic action of transglutaminase induced in human promyelocytic leukemia (HL-60) and human hepatoblastoma (HepG2) cells

Transglutaminase is a calcium-dependent enzyme that catalyzes an amine incorporation and a cross-linking of proteins. Intracellular transglutaminase is induced when human promyelocytic leukemia HL-60 cells are treated with retinoic acid and human hepatoblastoma HepG2 cells, with interleukin-6. To find whether the intracellular reaction catalyzed by transglutaminase increased when the enzyme is induced in these cells, the transglutaminase-catalyzed incorporation of 14C-labeled methylamine into cellular proteins was measured. The incorporation level of the labeled methylamine into proteins of HL-60 and HepG2 cells did not increase after the transglutaminase had been induced. The presence of the calcium ionophore A23187 did not affect these results. These findings suggested that even after the enzyme induction the catalytic action of intracellular transglutaminase is maintained at a constant level in these cells by unknown regulatory mechanism(s).

Relationship between morphological diversity and AgNORs or cathepsin B expression in colorectal cancers

The biological characteristics associated with the morphological diversity of colorectal cancers were investigated to elucidate the causes of this diversity. We examined the proliferative and infiltrating activity of tumor cells, indicated by the mean number of Ag nucleolar organizer region associated proteins (NORs) per nucleus (MNA) and the immunohistochemical response to cathepsin B(CB), in various morphological types of early and advanced colorectal cancers. We examined 73 colorectal cancers obtained by endoscopic and surgical resection. MNA values for sessile and flat-elevated cancers were greater than the values for pedunculate, subpedunculate, and flat-or-depressed early cancers (sessile, P < 0.05). In advanced cancers invading the muscularis propria, protruding cancers showed significantly higher MNA values than small ulcerative cancers (P < 0.01). CB expression increased significantly with the progression of colorectal cancers (P < 0.01), but was not related to morphological diversity in early and advanced cancers. In both sessile and flat cancers, CB expression was higher in moderately differentiated than in well differentiated adenocarcinomas. These results indicate that, in colorectal cancers, protruding early cancers without stalks and protruding advanced cancers have higher proliferative activity than pedunculate or flat early cancers and small ulcerative advanced cancers, respectively, and that CB expression is not associated with morphological diversity, but with depth of invasion and histological differentiation.

Catalytic activities of hammerhead ribozymes with a triterpenoid linker instead of stem/loop II

A minizyme is a hammerhead ribozyme with short oligonucleotide linkers instead of stem/loop II. In a previous study we demonstrated that a minizyme with high-level activity forms a dimeric structure with a common stem II (Amontov and Taira, J. Am. Chem. Soc., 118 (1996) 1624-1628). As a continuation of this study, we recently examined whether a short oligonucleotide linker at stem/loop II could be replaced by a triterpenoid linker and whether the resulting minizymes with bulky hydrophobic groups would form dimeric structures. In contrast to the minizyme with high-level activity that we characterized in the previous study, minizymes that contained a triterpenoid group had low cleavage activities. The nature of the dependence of the activity on the concentration of ribozyme revealed that these minizymes with a triterpenoid group do not form dimeric structures. Thus, the low activities of these structures can be attributed to their failure to form dimers.

Gallbladder cancer. A comparative study among clinicopathologic features, AgNORs, and DNA content analysis

A comparative study among clinicopathologic features, silver-stained nucleolar organizer region associated proteins (AgNORs), and DNA content analysis in 76 patients with gallbladder cancer was performed. The AgNOR count, AgNOR area, and the ration of AgNOR area to nuclear area were significantly higher in patients with a low grade of histological differentiation and deep invasion into the gallbladder wall. Moreover, these parameters were higher in cases with lymph node involvement and distant metastases. DNA ploidy pattern and clinicopathologic features showed to statistical significance. Our results demonstrate that AgNOR parameters are useful indicators to evaluate the malignant behavior of gallbladder cancer. Furthermore, the AgNOR count together with the depth of the neoplastic invasion and lymph node metastases proved to be independent prognostic factors for survival in patients with gallbladder cancer.

Entire hemithorax irradiation following complete resection in patients with stage II-III invasive thymoma

PURPOSE

To evaluate the feasibility and efficacy of prophylactic entire hemithorax irradiation (EH) in addition to mediastinal irradiation (MRT) following a complete resection in Stage II-III invasive thymoma.

METHODS AND MATERIALS

Forty-three patients with invasive thymoma treated with surgery and radiation therapy between 1978 and 1993 were analyzed retrospectively. All 43 patients underwent a complete surgical resection and were judged to have Masaoka's Stage II-III invasive thymoma. Of these, 23 patients received EH and MRT (EH-MRT) and the remaining 20 received MRT. Of the 23 patients with EH-MRT, 11 were Stage II and 12 Stage III. Of the 20 with MRT, 11 were Stage II and 9 Stage III. In most cases, EH was 15 Gy per 15 fractions over 3 weeks (without lung compensation calculation). In both the EH-MRT and MRT group, the total radiation doses to the mediastinum were similar with a median of 40 Gy. The median follow-up time after surgery was 63 months and no patients were lost to follow-up.

RESULTS

Only one of the 23 patients with EH-MRT relapsed. On the other hand, eight of the 20 with MRT relapsed, six of whom died of disease. The pleura was the most common site of failure. At 5 years, the relapse-free rate was 100% for those receiving EH-MRT and 66% for those with MRT (p = 0.03); the overall survival rate was 96% for those with EH-MRT, and 74% for those with MRT (p: not significant). The only significant treatment-related complication was radiation pneumonitis requiring treatment, in one patient who received MRT and three who received EH-MRT, including one death of a 72-year-old man and one 68-year-old woman with severe lung fibrosis.

CONCLUSION

Except for elderly patients, EH-MRT following a macroscopically complete resection appears to be safe and feasible, and can reduce intrathoracic relapses.

Solution structure of bromelain inhibitor IV from pineapple stem: structural similarity with Bowman-Birk trypsin/chymotrypsin inhibitor from soybean

Bromelain inhibitor VI from pineapple stem (BI-VI) is a unique double-chain inhibitor with an 11-residue light chain and a 41-residue heavy chain by disulfide bonds and inhibits the cysteine proteinase bromelain competitively. The structure of BI-VI in aqueous solution was determined using nuclear magnetic resonance spectroscopy and simulated annealing-based calculations. Its three-dimensional structure was shown to be composed of two distinct domains, each of which is formed by a three-stranded antiparallel beta-sheet. Unexpectedly, BI-VI was found to share a similar folding and disulfide bond connectivities not with cystatin superfamily inhibitors which inhibit the same cysteine proteinases but with the Bowman-Birk trypsin/chymotrypsin inhibitor from soybean (BBI-I). BBI-I is a 71-residue inhibitor which has two independent inhibitory sites toward the serine proteinases trypsin and chymotrypsin. These structural similarities with BBI-I suggest that they have evolved from a common ancestor and differentiated in function during a course of molecular evolution.

Overexpression of the gene for N-acylamino acid racemase from Amycolatopsis sp. TS-1-60 in Escherichia coli and continuous produciton of optically active methionine by a bioreactor

A DNA sequence encoding N-acylamino acid racemase (AAR) was inserted downstream from the T7 promoter in pET3c. The recombinant plasmid was introduced into Escherichia coli MM 294 lysogenized with a bacteriophage lambda having a T7 RNA polymerase gene. The amount of AAR produced by the E. coli transformant was 1100-fold more than that produced by Amycolatopsis sp. TS-1-60, the DNA donor strain. The AAR was purified to homogeneity from the crude extract of the E. coli transformant by two steps: heat treatment and Butyl-Toyopearl column chromatography. Bioreactors for the production of optically active amino acids were constructed with DEAE-Toyopearl-immobilized AAR and D- or L-aminoacylase. D- or L-methionine was continuously produced with a high yield from N-acetyl-DL-methionine by the bioreactor.

[Whole mediastinal irradiation with or without entire hemithoracic irradiation for invasive thymoma]

We retrospectively reviewed the case histories of 45 patients with invasive thymoma who underwent postoperative or definitive radiotherapy. Patients in stage II or stage III were classified according to the treatment volume as follows: a) those who received irradiation confined to the primary tumor site with a generous margin (involved field group, n = 17) and b)those who received prophylactic whole mediastinal irradiation with or without entire hemithoracic irradiation (prophylactic group, n = 21). Seven recurrences were observed among the involved field group, while all patients in the prophylactic group were relapse-free and alive after a median follow-up interval of 50 months. Major side effects were observed in two patients who received entire hemithoracic irradiation. One developed severe pneumonitis resulting in lung fibrosis that required hospitalization, while the other developed nephrotic syndrome of unknown cause. We conclude that whole mediastinal irradiation with or without entire hemithoracic irradiation can be used as a treatment of choice for postoperative invasive thymoma.

Primary structure, sequence-specific 1H-NMR assignments and secondary structure in solution of bromelain inhibitor VI from pineapple stem

One of the bromelain inhibitors, isoinhibitor VI (BI-VI), was purified from pineapple stem powder and its complete amino acid sequence was determined by conventional protein sequencing. These results revealed that the protein consists of an 11-residue light chain and a 41-residue heavy chain, cross-linked to each other by disulfide bonds to form the native inhibitor of 52 residues (M(r) = 5888). The secondary structure of BI-VI was analyzed based on the sequence-specific 1H resonance assignment of its two-dimensional NMR spectra. BI-VI was shown to be composed of two domains (A and B) which are formed by antiparallel beta-sheets, but has no alpha-helix. These results were consistent with the CD spectra of BI-VI. Residues Lys27-Ile29 (heavy chain) form a triple-stranded antiparallel beta-sheet with residues Asp9-Tyr11 and Lys22-Glu24 (heavy chain) in the A domain and residues Cys5-Cys7 (heavy chain) form another triple-stranded beta-sheet with residues Cys6-Cys8 (light chain) and Asp32-Ile34 (heavy chain) in the B domain. The secondary structure as well as the primary structure of BI-VI was distinctly different from that of the other cysteine protease inhibitor, cystatin, and from that of basic pancreatic trypsin inhibitor.

[Correlation analysis between patlak plot and DAR using 11C-methionine PET]

Seven patients were studied with positron emission tomography (PET) using 11C-methionine. All had non-Hodgkin's lymphoma but one, who had Hodgkin's disease. By assuming a simple three-compartment model for dynamic data analysis, we used the graphic method proposed by Patlak et al., where Ki (K2K3/(K1+K3)) was compared with DAR (differential absorption ratio). Trichloroacetate was added to each plasma sample, and the activity of the acid-soluble fraction was counted to eliminate the influence of the protein-bound fraction of injected activity. Patlak data plots, using this acid-soluble fraction as an input factor, showed good linearity over the time of data collection. All tumors showed clear 11C-methionine accumulation. Tumor activity reached almost a plateau within 10 min and was kept at the same level for at least 30 min. Ki and DAR were 0.070 +/- 0.035 and 4.64 +/- 1.85 (mean +/- SD), respectively. There was no apparent correlation between histological type and Ki or DAR, while the correlation efficient between Ki and DAR was 0.875. Our conclusion is that DAR will give almost the same result as dynamic data in the analysis of methionine metabolism using PET.

Agraphia and acalculia after a left prefrontal (F1, F2) infarction

A patient presented with agraphia and acalculia associated with a left frontal (F1, F2) infarction. He made mainly phonological but also lexical errors in writing (syllabograms), but his ability to write kanji (morphograms) was relatively preserved. Although he could add and subtract numbers, he could neither multiply nor divide them because of a difficulty in retrieving the multiplication tables and calculation procedures. Positron emission tomography showed decreased cerebral blood flow and metabolism limited to the infarct site. These findings suggest that agraphia and acalculia may occur associated with a left prefrontal lesion, and that the retrieval of arithmetic processes is modality specific.

Purification and properties of thermostable N-acylamino acid racemase from Amycolatopsis sp. TS-1-60

Thermostable N-acylamino acid racemase from Amycolatopsis sp. TS-1-60, a rare actinomycete strain selected for its ability to grow on agar plates incubated at 40 degrees C, was purified to homogeneity and characterized. The relative molecular mass (M(r)) of the native enzyme and the subunit was estimated to be 300,000 and 40,000 on gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis respectively. The isoelectric point (pI) of the enzyme was 4.2. The optimum temperature and pH were 50 degrees C and 7.5 respectively. The enzyme was stable at 55 degrees C for 30 min. The enzyme catalyzed the racemization of optically active N-acylamino acids such as N-acetyl-L- or D-methionine, N-acetyl-L-valine, N-acetyl-L-tyrosine and N-chloroacetyl-L-valine. In addition, the enzyme also catalyzed the racemization of the dipeptide L-alanyl-L-methionine. By contrast, the optically active amino acids, N-alkyl-amino acids and methyl and ethyl ester derivatives of N-acetyl-D- and L-methionine were not racemized. The apparent Km values for N-acetyl-L-methionine and N-acetyl-D-methionine were calculated to be 18.5 mM and 11.3 mM respectively. The enzyme activity was markedly enhanced by the addition of divalent metal ions such as Co2+, Mn2+ and Fe2+ and was inhibited by addition of EDTA and P-chloromercuribenzoic acid. The similarity between the NH2-terminal amino acid sequence of the enzyme and that of Streptomyces atratus Y-53 [Tokuyama et al. (1994) Appl Microbiol Biotechnol 40:835-840] was above 80%.

Cloning, DNA sequencing and heterologous expression of the gene for thermostable N-acylamino acid racemase from Amycolatopsis sp. TS-1-60 in Escherichia coli

The gene encoding the novel enzyme N-acylamino acid racemase (AAR) was cloned in recombinant phage lambda-4 from the DNA library of Amycolatopsis sp. TS-1-60, a rare actinomycete, using antiserum against the enzyme. The cloned gene was subcloned and transformed in Escherichia coli JM105 using pUC118 as a vector. The AAR gene consists of an open-reading frame of 1104 nucleotides, which specifies a 368-amino-acid protein with a molecular mass of 39411Da. The molecular mass deduced from the AAR gene is in good agreement with the subunit molecular mass (40kDa) of AAR from Amycolatopsis sp. TS-1-60. The guanosine plus cytosine content of the AAR gene was about 70%. Although the AAR gene uses the unusual initiation codon GTG, the gene was expressed in Escherichia coli using the lac promoter of pUC118. The amount of the enzyme produced by the transformant was 16 times that produced by Amycolatopsis sp. TS-1-60. When the unusual initiation codon GTG was changed to ATG, the enzyme productivity of the transformant increased to more than 37 times that of Amycolatopsis sp. TS-1-60. In the comparison of the DNA sequence and the deduced amino acid sequence of AAR with those of known racemases and epimerases in data bases, no significant sequence homology was found. However, AAR resembles mandelate racemase in that requires metal ions for enzyme activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Linearized method: A new approach for kinetic analysis of central dopamine D(2) receptor specific binding

We proposed a new method (;linearized method') to analyze neuroleptic ligand-receptor specific binding in a human brain using positron emission tomography (PET). We derived the linear equation to solve four rate constants, k(3), k(4), k(5), k(6) from PET data. This method does not demand a radioactivity curve in plasma as an input function to the brain, and can perform fast calculations in order to determine rate constants. We also tested the nonlinearized method including nonlinear equations which is a conventional analysis using plasma radioactivity corrected for ligand metabolites as an input function. We applied these methods to evaluate dopamine D(2) receptor specific binding of [(11)C] YM-09151-2. The value of B(max)/K(d)=k(3)/k (4) obtained by the linearized method was 5.72+/-3.1 which was consistent with the value of 5.78+/-3.4 obtained by the nonlinearized method.