An assessment of histopathological criteria for infection in joint arthroplasty in rheumatoid synovium

Intraoperative frozen section is reported to be a reliable means of identifying occult infection for preoperative evaluation of arthroplasty. The aim of this study was to determine whether the reported histopathological criteria--the existence of more than 10 polymorphonuclear cells (PMN) per high-power field--is valuable for determination of infection during the arthroplasty of patients with rheumatoid arthritis (RA). The permanent histological sections of RA synovium were analysed to study the degree of infiltration of PMNs. Furthermore, in order to examine the penetrative distribution of PMNs within the synovial tissues, immunohistochemical staining of PMNs was performed. In addition, the clinical history, from the postoperative period to the present, was investigated in 46 patients (60 joints). The presence of early- and/or late-stage postoperative infection, the development of postoperative fever, the progression of erythrocyte sedimentation rate (ESR) (more than 30 mm per hour) and the changes in CRP (more than 10 mg per litre) were further examined and compared with the histopathological tissue analyses and findings. The results demonstrated the presence of more than five PMNs per high-power field, excluding surface fibrin and inflammatory exudate in at least five separate microscopic fields in 10 joints (16.7%) of nine patients, out of 60 joints of 46 patients, in which no postoperative infection was evident. As to the magnitude of penetrative distribution of PMNs in 10 joints, there was a trend of deepening infiltration among the patients with intensive PMN infiltration. In addition, no development of postoperative fever, CRP or continuous indications of high ESR values were evident in this group. As the existence of more than 10 PMN per high-power field was not absolutely indicative of occult infection, investigation of frozen section during arthroplasty should be carefully managed.

Lactone-ring-cleaving enzymes of microorganisms: their diversity and applications

Microbial lactonohydrolases (lactone-ring-cleaving enzymes) with unique characteristics were found. The Fusarium oxysporum enzyme catalyzes the reversible and stereospecific hydrolysis of aldonate lactones and D-pantolactone (D-PL), and is useful for the optical resolution of racemic PL. The Agrobacterium tumefaciens enzyme hydrolyzes several aromatic lactones, and catalyzes the stereospecific hydrolysis of PL like the Fusarium enzyme, but its selectivity is opposite. The Acinetobacter calcoaceticus enzyme catalyzing the specific hydrolysis of dihydrocoumarin belongs to serine-enzyme family, and is useful for enantioselective hydrolysis of methyl DL-beta-acetylthioisobutyrate and regioselective hydrolysis of methyl cetraxate. This enzyme also catalyzes the bromination of monochlorodimedon when incubated with H(2)O(2) and dihydrocoumarin.

Spectroscopic characterization of the photocycle intermediates of photoactive yellow protein

The absorption spectra of photocycle intermediates of photoactive yellow protein mutants were compared with those of the corresponding intermediates of wild type to probe which amino acid residues interact with the chromophore in the intermediate states. B and H intermediates were produced by irradiation and trapped at 80 K, and L intermediates at 193 K. The absorption spectra of these intermediates produced from R52Q were identical to those from wild type, whereas those from E46Q and T50V were 7-15 nm red-shifted as those in the dark states. The absorption spectra of M intermediates were measured by flash photolysis at room temperature. Those of Y42F, T50V, and R52Q were identical to that of wild type, whereas that of E46Q was 11 nm red-shifted. Assuming that the intermediates of mutants have a structure comparable to that of wild type, these findings suggest the following: Glu46 interacts with the chromophore throughout the photocycle, interaction between the chromophore and Thr50 as well as Tyr42 is lost upon the formation of M intermediate, and Arg52 never interacts with the chromophore directly. The hydrogen-bonding network around the phenolic oxygen of the chromophore would be thus maintained until L intermediate decays, and the global conformational change would take place by the loss of the hydrogen bond between the chromophore and Tyr42. This model conflicts with some of the results of previous crystallographic studies, suggesting that the reaction mechanism in the crystal may be different from that in solution.

Isolation and primary structural analysis of two conjugated polyketone reductases from Candida parapsilosis

Two conjugated polyketone reductases (CPRs) were isolated from Candida parapsilosis IFO 0708. The primary structures of CPRs (C1 and C2) were analyzed by amino acid sequencing. The amino acid sequences of both enzymes had high similarity to those of several proteins of the aldo-keto-reductase (AKR) superfamily. However, several amino acid residues in the putative active sites of AKRs were not conserved in CPRs-C1 and -C2.

Quality control of diphtheria tetanus acellular pertussis combined (DTaP) vaccines in Japan

Diphtheria tetanus acellular pertussis combined (DTaP) vaccines have been successfully used in Japan by controlling their potencies and toxicities with animal models. In accordance with the recent practical introduction of DTaP vaccines of various formulations, a question has been raised in other nations as to the efficacy of a quality control system based on animal tests and standard preparations. The World Health Organization issued its guidelines on the production and quality control of acellular pertussis vaccines in 1998 along with the concept of quality control by ensuring that production lots were consistent with clinical trial lots, rather than by comparing them with standard preparations in traditional laboratory tests. However, because it is not feasible to evaluate the combined use of vaccines from different manufacturers in a clinical study, the alternative trend of quality control may give rise to a difficulty in rationalizing the practical immunizations to use vaccines of different brands in a mixed consequence. A standardized national regulation system to ensure the equivalence of approved products would be essential for such an immunization practice. The success of the Japanese DTaP vaccination suggests the possibility of an effective quality control of DTaP vaccines by means of standardized test systems.

[Multimodal treatment including intraoperative irradiation for advanced pancreatic cancer with extended metastasis]

From January 1987 to December 1999, we treated 11 advanced pancreatic cancer patients with extended metastasis with multimodal treatment. Two patients received external radiation therapy (ERT) and systemic chemotherapy, 1 received intraoperative radiation therapy (IORT) and ERT and arterial infusion chemotherapy (AIC), 2 received IORT and AIC, 4 received only IORT, 2 received only AIC, and 15 did not receive any of these treatments. There was a significant difference in the survival rate between treatment and no treatment cases (median survival of 177 days and 109 days, respectively) (p = 0.04). A significant difference in the survival rate was also observed between IORT cases and no treatment cases (median survival of 212 days and 109 days, respectively) (p = 0.02). However, there was no significant difference in the survival rate between AIC cases and no treatment cases (median survival of 177 days and 109 days, respectively) (p = 0.10). Therefore, our experience suggests that multimodal treatment including intraoperative irradiation is effective for advanced pancreatic cancer patients with extended metastasis.

Glycolic acid production using ethylene glycol-oxidizing microorganisms

Screening for microorganisms oxidizing ethylene glycol to glycolic acid was carried out. Among stock cultures, several yeasts and acetic acid bacteria showed high glycolic acid producing activity. Pichia naganishii AKU 4267 formed the highest concentration of glycolic acid, 35.3 g/l, from 10% (v/v) ethylene glycol (molar conversion yield, 26.0%). Among soil isolates, Rhodotorula sp. 3Pr-126, isolated using propylene glycol as a sole carbon source, formed the highest concentration of glycolic acid, 25.1 g/l, from 10% (v/v) ethylene glycol (molar conversion yield, 18.5%). Rhodotorula sp. 3Pr-126 showed higher activity toward 20% (v/v) ethylene glycol than P. naganishii AKU 4267. Optimization of the conditions for glycolic acid production was investigated using P. naganishii AKU 4267 and Rhodotorula sp. 3Pr-126. Under the optimized conditions, P. naganishii AKU 4267 and Rhodotorula sp. 3Pr-126 formed 105 and 110 g/l of glycolic acid (corrected molar conversion yields, 88.0 and 92.2%) during 120 h of reaction, respectively.

Stability of blood carbon monoxide and hemoglobins during heating

The effects of heating on hemoglobin (Hb) and carbon monoxide (CO) levels in human blood were investigated by in vitro experiments. Head-space gas chromatography (HS-GC) using a molecular sieve 5A stationary phase and thermal conductivity detection was adopted for the measurement of CO gas, and spectrophotometric methods were used for the measurement of various Hb forms, protein and heme contents. Deteriorated absorbance spectra were observed for heat-treated blood samples, and double wavelength spectrophotometry was proven to give wrong percent saturation of carboxyhemoglobin content (% CO-Hb). The blood sample taken from one fatal fire casualty gave significantly higher % CO-Hb measured spectrophotometrically, compared to that by HS-GC. Control blood or purified Hb solution, which was saturated with CO in designated extent, was heated in a sealed vial. Under the incubation below 54 degrees C, all Hb forms were stable, except for oxyhemoglobin (Hb-O(2)), which was partially oxidized to met-hemoglobin (Met-Hb). In contrast, under the incubation at 65 degrees C, Met-Hb was denatured completely to be insoluble, and Hb-O(2) was partially denatured via Met-Hb formation. CO-Hb was resistant against heating. The difference of heat susceptibility and precipitability among Hb forms resulted in artificial increase of % CO-Hb. During heating, spontaneous CO was produced from blood.

[A case of pulmonary dirofilariasis]

A 76-year-old woman admitted to our hospital with abnormal shadow on chest X-ray. Computed tomography demonstrated the 2 x 2 cm of round, well defined tumor on right S6 segment which was suspected to be a malignant tumor. Partial resection was performed with video-assisted thoracotomy (VATS) and histological examination of quickly frozen specimen showed no malignancy. Then, histological examination of formalin fixed specimen showed dirofilariasis. It has been reported 97 cases of dirofilariasis in Japan so far. Although X-ray or biochemical and immunological examination of serum help to diagnose dirofilariasis, difinite diagnosis can be done only by histological evidence of resected specimen. Because of the difficulty for denial the malignant tumor, surgical treatment should be required.

Acid/azole complexes as highly effective promoters in the synthesis of DNA and RNA oligomers via the phosphoramidite method

The utility of various kinds of acid salts of azole derivatives as promoters for the condensation of a nucleoside phosphoramidite and a nucleoside is investigated. Among the salts, N-(phenyl)imidazolium triflate, N-(p-acetylphenyl)imidazolium triflate, N-(methyl)benzimidazolium triflate, benzimidazolium triflate, and N-(phenyl)imidazolium perchlorate have shown extremely high reactivity in a liquid phase. These reagents serve as powerful activators of deoxyribonucleoside 3'-(allyl N,N-diisopropylphosphoramidite)s or 3'-(2-cyanoethyl N,N-diisopropylphosphoramidite)s employed in the preparation of deoxyribonucleotides, and 3'-O-(tert-butyldimethylsilyl)ribonucleoside 2'-(N,N-diisopropylphosphoramidite)s or 2'-O-(tert-butyldimethylsilyl)ribonucleoside 3'-(N,N-diisopropylphosphoramidite)s used for the formation of 2'-5' and 3'-5' internucleotide linkages between ribonucleosides, respectively. The azolium salt has allowed smooth and high-yield condensation of the nucleoside phosphoramidite and a 5'-O-free nucleoside, in which equimolar amounts of the reactants and the promoter are employed in the presence of powdery molecular sieves 3A in acetonitrile. It has been shown that some azolium salts serve as excellent promoters in the solid-phase synthesis of oligodeoxyribonucleotides and oligoribonucleotides. For example, benzimidazolium triflate and N-(phenyl)imidazolium triflate can be used as effective promoters in the synthesis of an oligodeoxyribonucleotide, (5')CGACACCCAATTCTGAAAAT(3') (20mer), via a method using O-allyl/N-allyloxycarbonyl-protected deoxyribonucleoside 3'-phosphoramidites or O-(2-cyanoethyl)/N-phenoxyacetyl-protected deoxyribonucleotide 3'-phosphoramidite as building blocks, respectively, on high-cross-linked polystyrene resins. Further, N-(phenyl)imidazolium triflate is useful for the solid-phase synthesis of oligoribonucleotides, such as (5')AGCUACGUGACUACUACUUU(3') (20mer), according to an allyl/allyloxycarbonyl-protected strategy. The utility of the azolium promoter has been also demonstrated in the liquid-phase synthesis of some biologically important substances, such as cytidine-5'-monophosphono-N-acetylneuraminic acid (CMP-Neu5Ac) and adenylyl(2'-5')adenylyl(2'-5')adenosine (2-5A core).

Extreme discrepancy between macroscopic diagnosis and pathological findings of gallbladder cancer treated by hepatopancreatoduodenectomy

Diagnosis of gallbladder cancer in terms of invasion depth and spread is an important factor in determining cumulative survival after surgical treatment. However, diagnostic methods available at present occasionally fail to judge staging correctly. We report a case of gallbladder cancer which showed extreme discrepancy between the preoperative macroscopic and imaging diagnosis (positive direct invasion to the liver and invasion to the bile duct and duodenum through the serosal layer; S3, Hinf3, Binf2, and stage IV by the Japanese Society of Biliary Surgery classification) and the pathological findings (limited in vasion within the subserosal layer; ss, hinf0. binf0, and stage II). This discrepancy allowed us to perform curative treatment by hepatopancreatoduodenectomy, including extended right lobectomy of the liver, external bile duct resection, resection of the mesocolon, and lymph node dissection. Surgeons should aim for curability of advanced gallbladder cancer by radical resection until accurate methods for the preoperative diagnosis of cancer spread are available, because the clinical picture may be modified by inflammatory changes.

A quantitative in vitro assay for detecting biological activity of endotoxin using rabbit peripheral blood

The pyrogen test or the endotoxin test has been playing a crucial role in detecting endotoxin in parenteral drugs. The current test methods, however, have disadvantages such as requiring a relatively high number of animals or an inadequacy in direct evaluation of in vivo activity. We made an attempt to establish a new in vitro assay method that can overcome the shortcomings of the current assay methods. We standardized the system of tumor necrosis factor-alpha (TNF-alpha) induction from the peripheral blood of rabbits for assaying endotoxin activity. This in vitro assay showed a linear dose-response regression between 0.1 and 5.0 endotoxin units per milliliter of endotoxin and a definite homogeneity of variance by logarithmically transforming the endotoxin and TNF-alpha concentrations in the reaction mixtures at 5 h of incubation at 37 degrees C. The assay showed a definite correlation with the pyrogen test but not with the endotoxin test when endotoxins from various bacteria were tested.

Nifedipine induces gingival overgrowth in rats through a reduction in collagen phagocytosis by gingival fibroblasts

BACKGROUND

Nifedipine is used as a long-acting vasodilator, and a primary side effect is the induction of gingival overgrowth, which is characterized by an accumulation of collagenous components within the gingival connective tissue. To elucidate the mechanisms of nifedipine-induced gingival overgrowth, we investigated the effect of nifedipine on Type I collagen metabolism in the gingiva of rats.

METHODS

Twenty-day-old rats were fed a powdered diet containing or lacking nifedipine for 3 to 55 days. Immunohistochemical analysis with anti-Type I collagen antibody was employed to examine the density of Type I collagen in the gingival connective tissue. Total RNAs were isolated from mandibular molar gingiva on days 0, 3, 15, 30, and 55, and reverse transcription polymerase chain reaction was performed to investigate the mRNA levels of Type I collagen. In addition, we performed a flow cytometric analysis with collagen-coated latex beads and cultured fibroblasts derived from rat gingiva to measure collagen phagocytosis.

RESULTS

Immunohistochemical analysis revealed that Type I collagen was more prevalent in the connective tissue of nifedipine-treated gingiva than in controls on day 55. In the nifedipine-treated group, the expression of Type I collagen mRNA gradually decreased to 1.5% on day 55 compared to day 0. In the control group, Type I collagen mRNA also decreased to 32%; however, mRNA expression was significantly lower in the nifedipine-treated group than in the controls. When the rate of phagocytic cells derived from nifedipine-treated gingiva and controls was represented as the mean +/- SE of the percentage from 3 different experiments, the values were as follows: on day 15, 13.5 +/- 2.1% and 15.0 +/- 1.5%; on day 30, 12.2 +/- 4.3% and 34.5 +/- 6.7% in the nifedipine-treated and the control group, respectively, indicating that phagocytic cells were considerably fewer in the nifedipine-treated gingiva on day 30. This finding demonstrates that the decrease in phagocytosis caused by nifedipine appeared before the detection of severe macroscopic gingival overgrowth.

CONCLUSION

These findings suggest that the decrease in collagen degradation due to lower phagocytosis is closely associated with the increase in Type I collagen accumulation in nifedipine-treated rat gingiva.

Intercellular adhesion molecule-1 in patients with idiopathic interstitial pneumonia

This study focuses on a possible role of intercellular adhesion molecule-1 (ICAM-1) in interstitial pulmonary diseases. We determined a soluble form of ICAM-1 in serum and bronchoalveolar lavage fluid (BALF) using ELISA in patients with usual interstitial pneumonia (UIP), bronchiolitis obliterance organizing pneumonia (BOOP), or nonspecific interstitial pneumonia (NSIP). In addition, we investigated the expression of ICAM-1 in the lung tissues of these patients by means of immunohistochemical staining. Serum levels of soluble ICAM-1 were significantly higher in patients with UIP or NSIP than in healthy subjects, and were also high in patients with BOOP. The soluble ICAM-1 in BALF tended to be higher in patients with UIP, BOOP, or NSIP than in normal subjects. A significant correlation was seen between soluble levels of ICAM-1 in serum and BALF. In the immunostaining of ICAM-1 of the lung tissues, ICAM-1 expression was more pronounced in patients with UIP than in those with BOOP or NSIP. The increased expression of ICAM-1 was seen in type II alveolar epithelium and vascular endothelium in patients with interstitial pneumonia. A positive correlation was observed between the degree of ICAM-1 expression in the lung tissues and the BALF levels of soluble ICAM-1. The expression of ICAM-1 in type II alveolar epithelium suggests that ICAM-1 plays a specific role in the fibrotic process of the lung, and that the measurement of soluble ICAM-1 in sera and BALF could be a useful marker for evaluating the progression of fibrosis.

Low-temperature Fourier transform infrared spectroscopy of photoactive yellow protein

The photocycle intermediates of photoactive yellow protein (PYP) were characterized by low-temperature Fourier transform infrared spectroscopy. The difference FTIR spectra of PYP(B), PYP(H), PYP(L), and PYP(M) minus PYP were measured under the irradiation condition determined by UV-visible spectroscopy. Although the chromophore bands of PYP(B) were weak, intense sharp bands complementary to the 1163-cm(-1) band of PYP, which show the chromophore is deprotonated, were observed at 1168-1169 cm(-1) for PYP(H) and PYP(L), indicating that the proton at Glu46 is not transferred before formation of PYP(M). Free trans-p-coumaric acid had a 1294-cm(-1) band, which was shifted to 1288 cm(-1) in the cis form. All the difference FTIR spectra obtained had the pair of bands corresponding to them, indicating that all the intermediates have the chromophore in the cis configuration. The characteristic vibrational modes at 1020-960 cm(-1) distinguished the intermediates. Because these modes were shifted by deuterium-labeling at the ethylene bond of the chromophore while labeling at the phenol part had no effect, they were attributed to the ethylene bond region. Hence, structural differences among the intermediates are present in this region. Bands at about 1730 cm(-1), which show that Glu46 is protonated, were observed for all intermediates except for PYP(M). Because the frequency of this mode was constant in PYP(B), PYP(H), and PYP(L), the environment of Glu46 is conserved in these intermediates. The photocycle of PYP would therefore proceed by changing the structure of the twisted ethylene bond of the chromophore.

Amino acids in the N-terminal region regulate the photocycle of photoactive yellow protein

The spectroscopic properties of photoactive yellow protein (PYP) partially digested by chymotrypsin were studied. Chymotrypsin yielded three major products that were yellow but distinguishable by SDS-PAGE. They were readily separated by DEAE-Sepharose column chromatography. Protein sequencing and mass spectrometry demonstrated that chymotrypsin cleaved the N-terminal 6, 15, or 23 amino acids (T6, T15, and T23). The blue-shifts of the absorption maxima and the increases in the apparent pK(a) of the chromophores relative to those of intact PYP were less than 4 nm and 0.2, respectively. The absorption spectra of the near-UV intermediates produced from T6, T15, and T23 were identical to that of intact PYP, but with lifetimes that were 140, 2,300, and 4,500 times longer, respectively. These observations suggest that the recovery of the dark state of PYP from the near-UV intermediate is accelerated by the N-terminal region, and that this region acts as a regulatory factor for the photocycle of PYP.

Direct observation of three conformations of MutS protein regulated by adenine nucleotides

Mismatched base-pairs, which are caused by either DNA replication errors, DNA damage or genetic recombination, are repaired by the mismatch-repair system. The MutS protein, a component of the mismatch-repair system, recognizes mismatched base-pairs in DNA, and its DNA-binding activity is affected by ATP and ADP. Here, we show that the MutS protein from Thermus thermophilus HB8 can have three different conformations in solution, based on direct observations made by small-angle X-ray scattering. The conformation of MutS in solution is drastically influenced by the presence of ADP and ATP; the ATP-bound form has the most compact conformation, the ADP-bound form the most stretched, and the nucleotide-free form has a conformation intermediate between the two. Based on these findings, we conclude that the DNA-binding activity of MutS may depend on conformational changes triggered by both the binding and hydrolysis of ATP.

Rapid determination of cyanide and azide in beverages by microdiffusion spectrophotometric method

A rapid screening method was developed for the determination of the toxic volatile anions, cyanide and azide, in beverages. This method consisted of a microdiffusion extraction combined with spectrophotometry using the Konig cyanide reaction and ferric azide complex formation in conjugation with cerium azide oxido-reduction. The time required to achieve full recovery in the extraction of hydrogen cyanide and hydrazoic acid from samples was considerably shortened by increasing the diffusion temperature from 25 degrees C to 40 degrees C. The time required to achieve saturated color development in the Konig cyanide reaction was also shortened by increasing incubation temperature to 40 degrees C. The interference in both azide color reactions was examined for volatile compounds. Cyanide interfered only in the case of ferric azide complex formation. Sulfide, sulfate, nitrite, and acetic acid interfered in both the color reactions. The established method gave a detection limit of 6 microM for cyanide and 0.5mM for azide, and it required only 1 h to determine both anions. Cyanide and azide disappeared by evaporation from beverages during 25 degrees C storage under open conditions in a pH-dependent manner as a function of their respective pKa values of 9.2 and 4.6.

Cloning and characterization of a novel serine/threonine protein kinase gene expressed predominantly in developing brain

We have isolated a rat gene, sbk, that encodes a novel serine/threonine protein kinase possessing a consensus sequence for an SH3-binding domain from developing rat brain. Rat SBK comprises 417 amino-acid residues consisting of a serine/threonine protein kinase consensus sequence followed by a C-terminal proline-rich region. Sequence comparison with other known kinases revealed that sbk belongs to a novel family of serine/threonine protein kinases structurally related to a Xenopus gastrula-specific protein kinase, Pk9.7. An in vitro kinase assay demonstrated that the SBK protein autophosphorylates at serine/threonine residues. Transcripts of sbk were strongly detected in brain, and the distribution shows an association with neurons but not glial cells. A marked increase in sbk transcripts was observed in developing brain in the late embryonic stage when dramatic neuronal proliferation, migration, and maturation occur. Fluorescence in situ hybridization analysis was used to map sbk to mouse chromosome 7F1-F3 and rat chromosome 1q21. These data suggest a role for SBK in signal-transduction pathways related to the control of brain development.

Effect of pedological characteristics on aqueous soil extraction recovery and tert-butyldimethylsilylation yield for gas chromatography-mass spectrometry of nerve gas hydrolysis products from soils

Detection and identification of alkyl methylphosphonate (RMPA) and methylphosphonate (MPA) are performed to verify the existence of nerve gases by gas chromatography-mass spectrometry (GC-MS) after tert-butyldimethylsilylation (TBDMS). However, it is sometimes difficult to detect RMPA and MPA in soils. This study examines the relationship between the pedological characteristics and the aqueous extraction recoveries and TBDMS derivatization yields of ethyl-, isopropyl- and pinacolyl methylphosphonate and MPA for 21 soil samples. The aqueous extraction recoveries were measured directly by capillary electrophoresis. Andosols showed low extraction recoveries, while Regosols and Fluvisols showed high recoveries. RMPA were extracted with higher recoveries than MPA from all soils. MPA could not be extracted from Andosols. Within the pedological characteristics, phosphate absorption coefficients showed a strong negative correlation with the extraction recoveries of all phosphonates. The levels of RMPA and MPA in aqueous soil extracts were also determined for eight soils by GC-MS after TBDMS. Compared to the aqueous extraction recoveries, the yields of TBDMS derivatives were low. Strong anion exchange led to a significant improvement in derivatization yields. The efficiencies of TBDMS derivatization were inversely correlated with the levels of alkaline earth metals extractable from soils when the three soils that possessed high total carbon were excluded.

Vascular endothelial growth factor secreted by replicating hepatocytes induces sinusoidal endothelial cell proliferation during regeneration after partial hepatectomy in rats

BACKGROUND

The aim of this study was to investigate regulatory mechanisms of sinusoidal endothelial cell (SEC) proliferation after hepatectomy in rats.

METHODS

We investigated expressions of vascular endothelial cell growth factor (VEGF) and its receptors, flt-1 and KDR/flk-1, in regenerating liver after 70% hepatectomy. Proliferation of both hepatocytes and SECs was also monitored by evaluating the proliferating cell nuclear antigen (PCNA) labeling index. Furthermore, VEGF production by cultured hepatocytes isolated at different times after hepatectomy was measured in vitro.

RESULTS

The expression of VEGF mRNA was increased markedly between 48 and 72 h after hepatectomy, and thereafter decreasing gradually. The immunohistochemical staining revealed that expression of VEGF started to increase 24 h after hepatectomy, with a peak at 72 h, and the majority of the VEGF-positive cells were hepatocytes located in periportal areas. Meanwhile, expression of flt-1 and KDR/flk-1 was observed along the sinusoids even before hepatectomy, but was increased between 72 and 120 h. Furthermore, VEGF production by cultured hepatocytes isolated 72 h after hepatectomy was significantly increased. The PCNA labeling index of the SECs exhibited a delayed and slower regenerative response in comparison to the hepatocytes, reaching a peak at 72 h.

CONCLUSIONS

These data strongly suggest that VEGF secreted by proliferating hepatocytes may represent an important stimulator of SEC proliferation.

Synthesis of optically pure ethyl (S)-4-chloro-3-hydroxybutanoate by Escherichia coli transformant cells coexpressing the carbonyl reductase and glucose dehydrogenase genes

The asymmetric reduction of ethyl 4-chloro-3-oxobutanoate (COBE) to ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE) was investigated. Escherichia coli cells expressing both the carbonyl reductase (S1) gene from Candida magnoliae and the glucose dehydrogenase (GDH) gene from Bacillus megaterium were used as the catalyst. In an organic-solvent-water two-phase system, (S)-CHBE formed in the organic phase amounted to 2.58 M (430 g/l), the molar yield being 85%. E. coli transformant cells coproducing S1 and GDH accumulated 1.25 M (208 g/l) (S)-CHBE in an aqueous monophase system by continuously feeding on COBE, which is unstable in an aqueous solution. In this case, the calculated turnover of NADP+ (the oxidized form of nicotinamide adenine dinucleotide phosphate) to CHBE was 21,600 mol/mol. The optical purity of the (S)-CHBE formed was 100% enantiomeric excess in both systems. The aqueous system used for the reduction reaction involving E. coli HB101 cells carrying a plasmid containing the S1 and GDH genes as a catalyst is simple. Furthermore, the system does not require the addition of commercially available GDH or an organic solvent. Therefore this system is highly advantageous for the practical synthesis of optically pure (S)-CHBE.

Primary Photoreaction of Photoactive Yellow Protein Studied by Subpicosecond−Nanosecond Spectroscopy

The primary photochemical event of photoactive yellow protein (PYP) was studied by laser flash photolysis experiments on a subpicosecond-nanosecond time scale. PYP was excited by a 390-nm pulse, and the transient difference absorption spectra were recorded by a multichannel spectrometer for a more reliable spectral analysis than previously possible. Just after excitation, an absorbance decrease due to the stimulated emission at 500 nm and photoconversion of PYP at 450 nm were observed. The stimulated emission gradually shifted to 520 nm and was retained up to 4 ps. Then, the formation of a red-shifted intermediate with a broad absorption spectrum was observed from 20 ps to 1 ns. Another red-shifted intermediate with a narrow absorption spectrum was formed after 2 ns and was stable for at least 5 ns. The latter is therefore believed to correspond to I1 (PYP(L)), which has been detected on a nanosecond time scale or trapped at -80 degrees C. Singular value decomposition analysis demonstrated that the spectral shifts observed from 0.5 ps to 5 ns could be explained by two-component decay of excited state(s) and conversion from PYP(B) to PYP(L). The amount of PYP(L) at 5 ns was less than that of photoconverted PYP, suggesting the formation of another intermediate, PYP(H). In addition, the absorption spectra of these intermediates were calculated based on the proposed reaction scheme. Together, these results indicate that the photocycle of PYP at room temperature has a branched pathway in the early stage and is essentially similar to that observed under low-temperature spectroscopy.

Roles of amino acid residues near the chromophore of photoactive yellow protein

To investigate the roles of amino acid residues around the chromophore in photoactive yellow protein (PYP), new mutants, Y42A, E46A, and T50A were prepared. Their spectroscopic properties were compared with those of wild-type, Y42F, E46Q, T50V, R52Q, and E46Q/T50V, which were previously prepared and specified. The absorption maxima of Y42A, E46A, and T50A were observed at 438, 469, and 454 nm, respectively. The results of pH titration for the chromophore demonstrated that the chromophore of PYP mutant, like the wild-type, was protonated and bleached under acidic conditions. The red-shifts of the absorption maxima in mutants tended toward a pK(a) increase. Mutation at Glu46 induced remarkable shifts in the absorption maxima and pK(a). The extinction coefficients were increased in proportion to the absorption maxima, whereas the oscillator strengths were constant. PYP mutants that conserved Tyr42 were in the pH-dependent equilibrium between two states (yellow and colorless forms). However, Y42A and Y42F were in the pH-independent equilibrium between additional intermediate state(s) at around neutral pH, in which yellow form was dominant in Y42F whereas the other was dominant in Y42A. These findings suggest that Tyr42 acts as the hinge of the protein, and the bulk as well as the hydroxyl group of Tyr42 controls the protein conformation. In all mutants, absorbance at 450 nm was decreased upon flash irradiation and afterwards recovered on a millisecond time scale. However, absorbance at 340--370 nm was increased vice versa, indicating that the long-lived near-UV intermediates are formed from mutants, as in the case of wild-type. The lifetime changes with mutation suggest the regulation of proton movement through a hydrogen-bonding network.

The role of fibronectin in bronchoalveolar lavage fluid of asthmatic patients

Allergic and chronic inflammation of the airway is regarded as the main pathogenesis of bronchial asthma, in which adhesion of inflammatory cells requires the expression of adhesion molecules. Thus, to clarify the role of fibronectin (FN) in the airway inflammation of bronchial asthma, FN levels in plasma and bronchoalveolar lavage fluid (BALF) from bronchial asthmatics were determined. FN concentrations in plasma and BALF were measured by enzyme-linked immunosorvent assay (ELISA) in 17 asthmatic patients and 10 healthy controls to elucidate the role of FN in allergic inflammation. The mean FN/albumin (Alb) level in the BALF of asthmatic patients was 2.973 micrograms/mg, which was significantly higher than that of healthy controls (0.727 microgram/mg). Non-atopic asthmatics showed a significantly higher level of FN in their BALF in comparison with atopic asthmatics, although the ratio of FN to albumin showed no significant difference. FN levels in BALF correlated significantly with total cell density (r = 0.71, P < 0.05) and alveolar macrophage density (r = 0.64, P < 0.05). FN levels in plasma did not correlate with those in BALF. In conclusion, increased FN in BALF, which was produced locally in the airways of asthmatic patients, is actively involved in the regulation of allergic inflammation.

Nucleotide synthesis via methods without nucleoside-base protection

Oligonucleotide synthesis via methods without nucleobase protection (N-unprotected methods) is briefly reviewed. The N-unprotected methods are advantageous in the following respects over conventional approaches that use protectors, generally, acyl protectors for the nucleobase (N-protected method). Two steps, introduction and removal of the protecting groups, are eliminated, and consequently use of undesirable reagents involved in these steps are avoided. In the synthesis of DNA oligomers, the risk of depurination of deoxyadenosine and deoxyguanosine derivatives, which is a serious problem in the N-protected methods, is considerably reduced. The range of synthesizable artificial analogues bearing base-labile functions is extended because harsh base treatment for the deprotection is eliminated.

Plasma fibronectin in asthmatic patients and its relation to asthma attack

This study investigated the relation between asthma attacks and levels of plasma fibronectin (FN) and serum eosinophilic cationic protein (ECP) in patients with bronchial asthma in order to clarify the role of FN in the airway inflammation of bronchial asthma. Plasma levels of FN were significantly higher (P < 0.025) in patients with bronchial asthma than in healthy controls. They were also significantly higher (P < 0.05) in non-atopic asthmatics than in atopic asthmatics. Furthermore, plasma FN was lower during the attack than the non-attack stage (P < 0.025), and a significant increase of plasma FN was noted (P < 0.05) in asthmatics who had more severe and more frequent attacks. Serum levels of ECP were significantly higher during the attack than the non-attack stage (P < 0.005). An increase of plasma FN in the non-attack stage after attacks showed a significant correlation (P < 0.05) with a decrease of serum ECP. These observations clearly indicate that the decrease in plasma FN associated with attacks is closely related to aggravation of airway inflammation, and that the increase in plasma FN in the non-attack stage reflects chronic airway inflammation. These results suggest that the fluctuation in plasma levels of FN may be one of the factors affecting allergic inflammation and attacks in bronchial asthma.

A family of multiple endocrine neoplasia type 2A with the RET proto-oncogene mutation in codon 618 (Cys-->Arg)

Multiple endocrine neoplasia type 2 (MEN-2) is a hereditary syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma and hyperplasia or adenoma of the parathyroid gland with hyperparathyroidism. Recent genetic studies have identified the presence of germline missense mutations in the RET proto-oncogene in almost 100% of MEN-2 patients. We report here three generations of one MEN-2 family with rare missense mutation at codon 618 (Cys-->Arg) of the RET proto-oncogene. The first patient was surgically treated at the age of 63 years but died of bone metastasis. His two children (29-year-old daughter and 25-year-old son) were treated surgically for MTC and neck lymph node metastasis. Germline mutations of the RET proto-oncogene of these three MTC patients and two children of the 29-year-old daughter (9-year-old female and 7-year-old male) were examined. Three MTC patients and the 9-year-old female possessed the mutation. The phenotype of the family with this rare point mutation of the RET proto-oncogene is reported.

N-phenylimidazolium triflate as a highly effective promoter for the interribonucleotide-bond formation via the phosphoramidite method

N-Phenylimidazolium triflate has been invented as an extremely effective promoter for the construction of interribonucleotide linkage according to the phosphoramidite strategy.

The complete nucleotide sequence of a plant root-inducing (Ri) plasmid indicates its chimeric structure and evolutionary relationship between tumor-inducing (Ti) and symbiotic (Sym) plasmids in Rhizobiaceae

The Ri (root-inducing) plasmid in Agrobacterium rhizogenes and Ti (tumor-inducing) plasmid in Agrobacterium tumefaciens have provided the fundamental basis for the construction of plant vectors and transgenic plants. Recently, the determination of the first complete nucleotide sequence of the Ti plasmid (pTi-SAKURA) has been successful. To understand the general structure of these oncogenic T-DNA transfer plasmids, the whole nucleotide sequence of a mikimopine-type Ri plasmid, pRi1724, was analyzed. The plasmid is 217,594 bp in size, and has 173 open reading frames (ORFs) in total, which are asymmetrically distributed. Except for 27 ORFs, which are unknown, 173 ORFs were classified into 12 groups as follows: three for DNA replication, nine for plasmid modification, 22 for conjugation, 26 for virulence, 11 for T-DNA gene, 19 for mikimopine/mikimopine-lactam transport, ten for an unknown opine metabolism, seven for transcriptional regulator, five for sugar transport, five for glycerol metabolism, four for chemoreceptor and 32 for others. The elucidated chimeric structure of pRi1724 interestingly indicates that the evolution of Rhizobiaceae plasmids seems to have kept interactions among the plasmids; especially, the genes and elements for a conjugal transfer of pRi1724 had clearly closer kinship to those of a Sym (symbiotic) plasmid, pNGR234a in Rhizobium sp. than those of Ti plasmids. By using sequencing and Northern analysis, we examined the metabolic pathway and gene expression of mikimopine, which is probably an Ri-specific opine.

Ethyl(methyl)dioxirane as an efficient reagent for the oxidation of nucleoside phosphites into phosphates under nonbasic anhydrous conditions

A convenient method for the oxidation of nucleoside phosphites into phosphates under nonbasic and nonaqueous conditions using commercially available ethyl(methyl)dioxirane has been developed. This oxidation is effective with both N-protected and N-unprotected strategies.

Light induces destabilization of photoactive yellow protein

To understand the effect of visible light on the stability of photoactive yellow protein (PYP), urea denaturation experiments were performed with PYP in the dark and with PYP(M) under continuous illumination. The urea concentrations at the midpoint of denaturation were 5.26 +/- 0.29 and 3.77 +/- 0.19 M for PYP and PYP(M), respectively, in 100 mM acetate buffer, and 5.26 +/- 0.24 and 4.11 +/- 0.12 M for PYP and PYP(M), respectively, in 100 mM citrate buffer. The free energy change upon denaturation (DeltaG(D)(H2O)), obtained from the denaturation curve, was 11.0 +/- 0.4 and 7.6 +/- 0.2 kcal/mol for PYP and PYP(M), respectively, in acetate buffer, and 11.5 +/- 0.3 and 7.8 +/- 0.1 kcal/mol for PYP and PYP(M), respectively, in citrate buffer. Even though the DeltaG(D)(H2O) value for PYP(M) is almost identical in the two buffer systems, the urea concentration at the midpoint of denaturation is lower in acetate buffer than in citrate buffer. Although their CD spectra indicate that the protein conformations of the denatured states of PYP and PYP(M) are indistinguishable, the configurations of the chromophores in their denatured structures are not necessarily identical. Both denatured states are interconvertible through PYP and PYP(M). Therefore, the free energy difference between PYP and PYP(M) is 3.4-3.7 kcal/mol for the protein moiety, plus the additional contribution from the difference in configuration of the chromophore.

Interfering effect of diphtheria-tetanus-acellular pertussis combined (DTaP) vaccines on the bacterial endotoxin test

We evaluated applicability of the endotoxin test to DTaP vaccines. Although no DTaP vaccine batches showed immediate interference with the activating activity of spiked endotoxin on the clotting of Limulus amaebocyte lysate (LAL), a gradually progressing interference depending on the time after spiking was seen for some of the batches. The interfering DTaP vaccine batches, however, showed no significant effect onin vitro TNF-alpha induction in RAW264.7 cells and pyrogenicity in rabbits of spiked endotoxin. Aluminium hydroxide gel in the vaccines was suggested to be one of the causes of the interference. Accordingly, a careful evaluation of the interfering effect was assumed crucial for the effective application of the endotoxin test to check residual biological activity of endotoxin in DTaP vaccines.

Solution structure of Grb2 reveals extensive flexibility necessary for target recognition

Grb2 is an adaptor protein composed of a single SH2 domain flanked by two SH3 domains. Grb2 functions as an important evolutionary conserved link between a variety of cell membrane receptors and the Ras/MAP kinase-signaling cascade. Here, we describe the solution structure of Grb2 as revealed by NMR and small angle X-ray scattering measurements. We demonstrate that Grb2 is a flexible protein in which the C-terminal SH3 domain is connected to the SH2 domain via a flexible linker. This is in contrast to the previously described Grb2 crystal structure, which showed a compact structure with intramolecular contact between two SH3 domains. Binding experiments on Grb2 and peptides containing two different proline-rich sequences indicate that Grb2 adapts the relative position and orientation of the two SH3 domains to bind bivalently to the target peptide sequences.

Antibacterial action of tryptanthrin and kaempferol, isolated from the indigo plant (Polygonum tinctorium Lour.), against Helicobacter pylori-infected Mongolian gerbils

We evaluated the effect of tryptanthrin and kaempferol, both isolated from Polygonum tinctorium Lour., against Helicobacter pylori colony formation in vitro and in H. pylori-infected Mongolian gerbils. H. pylori suspension was mixed with solution of tryptanthrin and/or kaempferol and placed onto agar plates. These plates were incubated at 37 degrees C, under 10% CO2 for 5 days, and the H. pylori colonies were counted. For the in vivo experiment, Mongolian gerbils were inoculated with H. pylori ATCC 43504 orally. After 4 weeks, the infected gerbils were given tryptanthrin and/or kaempferol, administered orally, twice a day for 10 days. The animals were killed and the number of live H. pylori in their stomachs was determined. In vitro both tryptanthrin and kaempferol significantly decreased the numbers of H. pylori colonies a dose-dependent manner. An additive effect on colony formation was observed with the combined use. In the in vivo experiment, oral administration of tryptanthrin and/or kaempferol significantly decreased the numbers of colonies in the gerbils' stomachs. We concluded that tryptanthrin and kaempferol were effective against H. pylori in vivo.

Time-resolved x-ray diffraction reveals multiple conformations in the M-N transition of the bacteriorhodopsin photocycle

We measured the M-N transition of wild-type bacteriorhodopsin (pH 9, 10 degrees C) by time-resolved x-ray diffraction study at SPring8 BL45XU-A. We confirmed the accumulation of M and N intermediates by absorbance measurements, and we found that the time resolution of x-ray diffraction experiments (244 ms) was sufficient to resolve the M-N transition. From the x-ray diffraction data, three components were decomposed by singular value decomposition analysis. The existence of three components in the M-->N-->BR reaction revealed that BR changes its structure during the M-N transition. Moreover, the difference Fourier maps of reconstituted fast and slow decay components clearly showed that the electron density distributions of the F helix changes in the M-N transition. The observed structural change at the F helix will increase access of the Schiff base and D96 to the cytoplasmic surface and facilitate the proton transfer steps that begin with the decay of the M state.

Light-induced conformational changes of rhodopsin probed by fluorescent alexa594 immobilized on the cytoplasmic surface

A novel fluorescence method has been developed for detecting the light-induced conformational changes of rhodopsin and for monitoring the interaction between photolyzed rhodopsin and G-protein or arrestin. Rhodopsin in native membranes was selectively modified with fluorescent Alexa594-maleimide at the Cys(316) position, with a large excess of the reagent Cys(140) that was also derivatized. Modification with Alexa594 allowed the monitoring of fluorescence changes at a red excitation light wavelength of 605 nm, thus avoiding significant rhodopsin bleaching. Upon absorption of a photon by rhodopsin, the fluorescence intensity increased as much as 20% at acidic pH with an apparent pK(a) of approximately 6.8 at 4 degrees C, and was sensitive to the presence of hydroxylamine. These findings indicated that the increase in fluorescence is specific for metarhodopsin II. In the presence of transducin, a significant increase in fluorescence was observed. This increase of fluorescence emission intensity was reduced by addition of GTP, in agreement with the fact that transducin enhances the formation of metarhodopsin II. Under conditions that favored the formation of a metarhodopsin II-Alexa594 complex, transducin slightly decreased the fluorescence. In the presence of arrestin, under conditions that favored the formation of metarhodopsin I or II, a phosphorylated, photolyzed rhodopsin-Alexa594 complex only slightly decreased the fluorescence intensity, suggesting that the cytoplasmic surface structure of metarhodopsin II is different in the complex with arrestin and transducin. These results demonstrate the application of Alexa594-modified rhodopsin (Alexa594-rhodopsin) to continuously monitor the conformational changes in rhodopsin during light-induced transformations and its interactions with other proteins.

Alteration of conformation and dynamics of bacteriorhodopsin induced by protonation of Asp 85 and deprotonation of Schiff base as studied by 13C NMR

According to previous X-ray diffraction studies, the D85N mutant of bacteriorhodopsin (bR) with unprotonated Schiff base assumes a protein conformation similar to that in the M photointermediate. We recorded (13)C NMR spectra of [3-(13)C]Ala- and [1-(13)C]Val-labeled D85N and D85N/D96N mutants at ambient temperature to examine how conformation and dynamics of the protein backbone are altered when the Schiff base is protonated (at pH 7) and unprotonated (at pH 10). Most notably, we found that the peak intensities of three to four [3-(13)C]Ala-labeled residues from the transmembrane alpha-helices, including Ala 39, 51, and 53 (helix B) and 215 (helix G), were suppressed in D85N and D85N/D96N both from CP-MAS (cross polarization-magic angle spinning) and DD-MAS (dipolar decoupled-magic angle spinning) spectra, irrespective of the pH. This is due to conformational change and subsequent acquisition of intermediate time-range motions, with correlation times in the order of 10(-)(5) or 10(-)(4) s, which interferes with proton decoupling frequency or frequency of magic angle spinning, respectively, essential for an attempted peak-narrowing to achieve high-resolution NMR signals. Greater changes were achieved, however, at pH 10, which indicate large-amplitude motions of transmembrane helices upon deprotonation of Schiff base and the formation of the M-like state in the absence of illumination. The spectra detected more rapid motions in the extracellular and/or cytoplasmic loops, with correlation times increasing from 10(-)(4) to 10(-)(5) s. Conformational changes in the transmembrane helices were located at helices B, G, and D as viewed from the above-mentioned spectral changes, as well as at 1-(13)C-labeled Val 49 (helix B), 69 (B-C loop), and [3-(13)C]Ala-labeled Ala 126 (D-helix) signals, in addition to the cytoplasmic and extracellular loops. Further, we found that in the M-like state the charged state of Asp 96 at the cytoplasmic side substantially modulated the conformation and dynamics of the extracellular region through long-distance interaction.

Contribution of CD95 ligand-induced neutrophil infiltration to the bystander effect in p53 gene therapy for human cancer

Clinical trials of adenoviral p53 gene therapy provide the evidence that the bystander effect induced by the wild-type p53 gene transfer on adjacent tumor cells contributes to tumor progression; its mechanism, however, remains uncharacterized. We report in this work that injection of adenovirus expressing the human wild-type p53 gene (Ad5CMVp53) into established human colorectal tumors in nu/nu mice resulted in CD95 ligand (CD95L) overexpression, followed by a massive neutrophil infiltration. Culture supernatants of human colorectal cancer cells infected with Ad5CMVp53 exhibited a potent chemotactic activity against murine polymorphonuclear neutrophils, which could be abolished by the anti-CD95L mAb (NOK-1). In vivo cell depletion experiments indicated that neutrophils were in part responsible for the antitumor effect of the Ad5CMVp53 infection. Our data directly suggest that overexpression of CD95L by the wild-type p53 gene transfer induces neutrophil infiltration into human colorectal tumors, which may play a critical role in the bystander effect of p53 gene therapy.

Pitfalls in the toxicological analysis of an isobutyl nitrite-adulterated coffee drink

A forensic investigation was carried out on one poisoning case, where cyanide was first detected in an evidence sample of a canned coffee drink. A more complete study revealed that it had been adulterated with isobutyl nitrite (IBN) and not cyanide. We examined the detectivity of IBN and related compounds by headspace gas chromatography and capillary electrophoresis. IBN decomposes to isobutyl alcohol (iBuOH) and nitrite in aqueous solution, and under higher temperature and more acidic conditions, the rate of this reaction becomes more rapid. IBN was also produced by the esterification of iBuOH with nitrite below pH 5. Cyanide was produced in a coffee solution by the addition of nitrite below pH 6. An IBN-spiked canned coffee drink solution was stored at 4 degrees C and periodically analyzed for IBN, iBuOH, nitrite, nitrate, and cyanide. Since the IBN level decreased rapidly, iBuOH was produced in an almost 90% molar yield. Nitrite production reached a maximum of 40% molar recovery on the first day and then gradually disappeared. The nitrate level reached a plateau of approximately 60% molar recovery. Cyanide was also detected, and its level at the 14th day was approximately 0.26% molar recovery. These findings suggest that, in a coffee drink solution, IBN undergoes hydrolysis to produce iBuOH and nitric acid, which is oxidized to nitrate and also produces cyanide through the nonspecific oxidation of organic compounds under acidic conditions.

[Pulmonary Nocardia otitidiscaviarum infection in an immunocompetent host]

A rare case of pulmonary Nocardia otitidiscaviarum (N. otitidiscaviarum) was encountered in an immunocompetent host. A 74-year-old man was admitted to our hospital with a high fever and a productive cough. His chest radiograph and CT scan revealed infiltrative shadows in the right middle and lower lung fields. Although several antibiotics (third-generation cephalosporin, minocycline, imipenem) were administered, the fever and cough persisted, and C-reactive protein remained elevated. Repeated sputum cultures showed normal flora, so a transbronchial lung biopsy and bronchoalveolar lavage (BAL) were performed bronchoscopically at the right S5. The BAL fluid contained acid-fast, branching filamentous structures. The microorganism was identified as N. otitidiscaviarum by the Research Center for Pathogenic Fungi and Microbial Toxicoses (Chiba University). Trimethoprim-sulfamethoxazole was therefore administered, but the fever continued to rise daily, and C-reactive protein remained elevated. This isolated N. otitidiscaviarum showed resistance to multiple antimicrobial agents in vitro when examined by the disk diffusion method, and so, on the basis of the antibiogram, the patient was treated with clarithromycin (oral, 600 mg/day) plus amikacin (400 mg/day), which proved successful. Testing for pulmonary nocardiosis should be added to the differential diagnosis procedures for refractory pneumonia as an opportunistic infection and for community-acquired pneumonia.

Extrahepatic large hepatocellular carcinoma with peritoneal dissemination: multimodal treatment, including four surgical operations

We report a patient with extrahepatically growing large hepatocellular carcinoma (HCC) associated with disseminated intraabdominal tumor and spontaneous tumor bleeding who was treated with four operations, transcatheter arterial embolization, systemic chemotherapy, and hyperthermia. It took 12 months for the multimodal treatment to normalize the alpha-fetoprotein (AFP) level, and remission continued for 6 months. We performed the fourth surgical treatment for a recurrent abdominal tumor involving the small intestine and mesentery, but the patient died 26 months after the first admission. Multimodal treatment, including repeat surgical treatments, for such advanced HCC should be encouraged, to prolong life and to maintain quality of life.

Severe complications of mediastinal pancreatic pseudocyst: report of esophagobronchial fistula and hemothorax

We report two patients with alcoholic pancreatic pseudocyst which communicated to the mediastinal space through the aortic hiatus, in one patient resulting in hypotensive shock due to hemothorax, and in the other, resulting in esophagobronchial fistula via the mediastinal cyst. The first patient was successfully treated by radical resection of the pancreatic body and tail, and the spleen, with an ultrasonic scalpel, although inflammatory changes caused by pancreatitis were so prominent that the splenic vein was occluded. The second patient could not be treated surgically, because the superior mesenteric vein had been occluded by chronic pancreatitis; he died of respiratory failure and sepsis due to aspiration pneumonia, despite receiving medical treatment.

Beneficial effects of verapamil on intestinal ischemia and reperfusion injury: pretreatment versus postischemic treatment

We studied the effect of verapamil on intestinal ischemia and reperfusion (I/R) injury. Intestinal ischemia was induced by clamping the superior mesenteric artery for 30 min followed by reperfusion. Magnetic resonance spectroscopy was employed as a marker of the changes in the energy metabolism. Further, histological changes and the changes of water contents were evaluated. Recovery rates of energy metabolism after intestinal I/R were improved by verapamil, administered before and after ischemia, and tissue edema was significantly reduced with verapamil. These findings suggest that verapamil results in an improved recovery of the energy metabolism and cellular preservation, presumably by reducing the intracellular calcium influx.