Characterization of xanthine oxidase from Cellulosimicrobium funkei possessing hypoxanthine-metabolizing activity

AIMS

Purine-degrading enzymes are favourable as medications and diagnostic tools for hyperuricemia. This study aimed to characterize enzymes isolated from micro-organisms, which may be useful for developing a new prophylaxis for hyperuricemia.

METHODS AND RESULTS

Cellulosimicrobium funkei A153 was found to be a good catalyst for hypoxanthine degradation and could oxidize hypoxanthine to xanthine and further to uric acid. The enzyme catalysing this oxidation was purified, and its partial amino acid sequences were examined. Based on this information and genome sequencing results, this xanthine dehydrogenase family protein was cloned and expressed in Rhodococcus erythropolis L88. The recombinant enzyme with a His-tag was characterized. The enzyme was a xanthine oxidase as it could utilize molecular oxygen as an electron acceptor. It was stable under 50°C and exhibited maximum activity at pH 7·0. The k_cat , K_m and k_cat /K_m values for xanthine were 1·4 s^-1 , 0·22 mmol l^-1 and 6·4 s^-1  mmol^-1  l, respectively.

CONCLUSIONS

Xanthine oxidase is favourable for hyperuricemia medication because it oxidizes hypoxanthine, an easily adsorbed purine, to xanthine and further to uric acid, which are hardly adsorbed purines.

SIGNIFICANCE AND IMPACT OF THE STUDY

The enzyme is useful for decreasing serum uric acid levels via conversion of easily absorbed purines to hardly absorbed purines in the intestine. Enzymes from micro-organisms may be used as a novel prophylaxis for hyperuricemia.

Surgical treatment of an abnormally positioned right adrenal tumor on segmental caudal vena cava aplasia in two dogs

Segmental caudal vena cava (CVC) aplasia is a rare congenital vascular anomaly in dogs. Two dogs were diagnosed by CT imaging to have right adrenal tumors with concomitant segmental CVC aplasia. During surgery, a firm connection between the right adrenal gland and CVC was observed in both cases. The adrenal glands were found ventral to the CVC and the adrenal tumor was resected including the vascular wall. CVC venectomy for tumor removal will be required if the right adrenal gland is displaced in dogs with segmental CVC aplasia, even if there is no intravascular invasion.

Synthesis and Glycan-Protein Interaction Studies of Se-Sialosides by 77Se NMR

To expand the potential of Se-carbohydrates for multifunctional mimicry of sugars, herein we addressed the synthesis of the highly challenging and biologically significant Se-glycosides of sialic acid (Se-sialosides). An α-sialyl selenolate anion generated in situ smoothly reacted with electrophiles to give α-Se-sialosides as single stereoisomers. A Se-sialoside was sequentially incorporated with selenium, producing a triseleno-sialoside. This molecule was used as a ⁷⁷Se NMR-active handle for studying glycan-protein interaction, revealing different binding profiles of sialic acid binding proteins.

Compartmentalized host spaces accommodating guest aromatic molecules in a chiral way in a helix-peptide-aromatic framework

A novel host molecular assembly of a free-standing flat nanosheet with compartmentalized spaces was prepared using a bolaamphiphilic peptide composed of two amphiphilic helical peptides and an oligo(naphthaleneethynylene) (ONE) unit at the center of the molecule. The nanosheet possesses void host spaces that can accommodate two mol-equivalent ONE groups to form columns of ONE groups in a right-handed helical way and ONE channels over a long distance. The present molecular system therefore can provide a chiral pore channel for relatively large molecules.

The anti-inflammatory effect of 10-oxo-trans-11-octadecenoic acid (KetoC) on RAW 264.7 cells stimulated with Porphyromonas gingivalis lipopolysaccharide

BACKGROUND

There is rapidly developing interest into the role of several anti-inflammatory agents to resolve inflammation in periodontal disease. A bioactive polyunsaturated fatty acid, 10-oxo-trans-11-octadecenoic acid (KetoC), is known to have various beneficial physiological effects; however, the effect of KetoC on inflammation remains unclear. Here, we investigated the effect of KetoC on RAW 264.7 cells stimulated with Porphyromonas gingivalis lipopolysaccharide, and explored the intracellular mechanism responsible for its anti-inflammatory effects.

METHODS

RAW 264.7 cells were pre-treated with or without KetoC, and then stimulated with or without P. gingivalis lipopolysaccharide. Levels of tumor necrosis factor α (TNFα), interleukin (IL)-6 and IL-1β were determined by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Specific antagonists for G protein-coupled receptor (GPR)40 and GPR120 were used to clarify the receptor for KetoC. The intracellular mechanism was investigated using western blotting analysis to separate nuclear and cytosolic NF-κB p65 protein.

RESULT

KetoC (5 μmol/L) was not toxic to RAW 264.7 cells, and significantly reduced the expression of TNFα and IL-6 mRNA and protein, and IL-1β mRNA. No protein production of IL-1β was observed. Additionally, when bound to GPR120, KetoC trended to downregulate nuclear NF-κB p65 protein levels. However, the antagonist for GPR40 failed to diminish the action of KetoC.

CONCLUSION

KetoC suppressed the proinflammatory cytokines TNFα, IL-6 and IL-1β via NF-κB p65, by binding to its receptor GPR120. KetoC is a promising candidate in future studies as a bioactive anti-inflammatory agent in treating periodontal disease.

Production of cis-11-eicosenoic acid by Mortierella fungi

AIM

To find cis-11-eicosenoic acid (20:1ω9, EA)-producing micro-organisms.

METHODS AND RESULTS

We found EA-producing fungi by screening about 300 fungal strains and identified a major fatty acid accumulated in the Mortierella fungi as EA by means of GC-MS analysis. In particular, Mortierella chlamydospora CBS 529.75 produced a high amount of EA (36.3 mg g(-1) of dried cells) on cultivation at 28°C for 4 days and then at 12°C for 3 days. In the result of lipid analysis, most of the EA was a component of triacylglycerols, not phospholipids.

CONCLUSION

We found that M. chlamydospora CBS 529.75 was the best producer for the microbial production of EA.

SIGNIFICANCE AND IMPACT OF THE STUDY

EA is beneficial as a raw material for medical supplies and a moisturizing component of cosmetic creams. This is the first report of microbial production of EA.

Identification of insulin-like growth factor 2 mRNA-binding protein 3 as a radioresistance factor in squamous esophageal cancer cells

Identification of reliable markers of radiosensitivity and the key molecules that donate susceptibility to anticancer treatments to esophageal cancer cells would be highly desirable. We found that the mRNA expression of insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) was higher in radioresistant TE-5 and TE-9 cells than in radiosensitive TE-12 cloneA1 cells. Conversely, knocking down expression of IGF2BP3 mRNA in TE-5 and TE-9 cells using small interfering RNA significantly enhanced their radiosensitivity. Furthermore, patients with squamous cell esophageal cancers strongly expressing IGF2BP3 tended to respond poorly to chemoradiation. These data suggest that IGF2BP3 may be a key marker of radiosensitivity that diminishes the susceptibility of squamous cell esophageal cancer cells to radiotherapy. IGF2BP3 may, thus, be a useful target for improving radiotherapy for patients with esophageal squamous cell carcinoma.

Outcomes of endoscopic and surgical resection for a second primary cancer in the residual cervical esophagus after thoracic esophagectomy

Patients who have received subtotal esophagectomy for thoracic esophageal cancer must be closely monitored for second primary malignancies. The purpose of this study is to review and assess patients who developed a second primary esophageal cancer in the residual cervical esophagus. Between 1996 and 2010, 10 patients were diagnosed in our hospital with esophageal squamous cell cancer in the residual cervical esophagus after undergoing thoracic esophagectomy and were treated with endoscopic or surgical resection. Data from these patients were reviewed retrospectively. Seven of the 10 patients (70%) had multiple primary carcinoma lesions at the time of their esophagectomy. A second primary cancer in the residual cervical esophagus was detected in eight patients during follow-up endoscopic examinations while the patients were still asymptomatic. Seven of the patients underwent endoscopic resection for a superficial cancer. None of those patients experienced any complications, and all are currently alive and cancer-free. The remaining three patients underwent resection of the cervical esophagus with regional lymph node dissection. Two of those patients experienced severe complications; one subsequently died (hospital death) from pneumonia, 12 months after surgery, while the other died from recurrence of his cancer. The third patient is alive and cancer-free. Early detection of a second primary malignancy in the residual cervical esophagus followed by endoscopic resection is the best treatment strategy for patients who previously received subtotal esophagectomy for thoracic esophageal cancer. Surgical resection puts patients at high risk of mortality or morbidity.

Nucleoside Oxidase, a Hydrogen Peroxide-Forming Oxidase, from Flavobacterium meningosepticum

A novel enzyme which catalyzes the oxidation of nucleosides to nucleoside-5(prm1)-carboxylic acids, forming hydrogen peroxide, was purified to homogeneity from Flavobacterium meningosepticum T-2799. The enzyme has a molecular weight of about 500,000, and four nonidentical subunits (molecular weights of 81,000, 69,000, 33,000, and 16,000) were detected on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. On the basis of visible absorption spectra of the purified enzyme, the enzyme is concluded to be a hemoprotein. It also contains covalently bound flavin adenine dinucleotide. The various nucleosides, such as adenosine (K(infm) = 48 (mu)M), inosine (K(infm) = 66 (mu)M), guanosine (K(infm) = 21 (mu)M), thymidine (K(infm) = 50 (mu)M), uridine (K(infm) = 80 (mu)M), and cytidine (K(infm) = 50 (mu)M), were oxidized by the enzyme, but nucleotides, bases, and ribose were not.

Small Cell Carcinoma of the Esophagus Treated with Esophagectomy and following Chemotherapy: Case Report with Review of the Literature

We report 2 cases of small cell carcinoma of the esophagus treated with esophagectomy as a primary treatment and following chemotherapy. One patient (pT1N1M0) achieved long-term survival, while the other patient (pT1N1M1-lym) died 18 months after surgery. We used reports on 47 Japanese patients receiving esophagectomy as a primary treatment to determine when esophagectomy for small cell carcinoma of the esophagus is indicated. We conclude that esophagectomy as a local treatment provides relatively good long-term survival only in patients without lymph node involvement.

Microbial production of conjugated gamma-linolenic acid from gamma-linolenic acid by Lactobacillus plantarum AKU 1009a

AIMS

Optimal production conditions of conjugated gamma-linolenic acid (CGLA) from gamma-linolenic acid using washed cells of Lactobacillus plantarum AKU 1009a as catalysts were investigated.

METHODS AND RESULTS

Washed cells of Lact. plantarum AKU 1009a exhibiting a high level of CGLA productivity were obtained by cultivation in a nutrient medium supplemented with 0.03% (w/v) alpha-linolenic acid as an inducer. Under the optimal reaction conditions with 13 mg ml(-1)gamma-linolenic acid as a substrate in 5 -ml reaction volume, the washed cells [32% (wet cells, w/v) corresponding to 46 mg ml(-1) dry cells] as the catalysts produced 8.8 mg CGLA per millilitre reaction mixture (68% molar yield) in 27 h. The produced CGLA was a mixture of two isomers, i.e., cis-6,cis-9,trans-11-octadecatrienoic acid (CGLA1, 40% of total CGLA) and cis-6,trans-9,trans-11-octadecatrienoic acid (CGLA2, 60% of total CGLA), and accounted for 66% of total fatty acid obtained. The CGLA produced was obtained as free fatty acids adsorbed mostly on the surface of the cells of Lact. plantarum AKU1009a.

CONCLUSION

The practical process of CGLA production from gamma-linolenic acid using washed cells of Lact. plantarum AKU 1009a was successfully established.

SIGNIFICANCE AND IMPACT OF THE STUDY

We presented the first example of microbial production of CGLA. CGLA produced by the process is valuable for evaluating their physiological and nutritional effects, and chemical characteristics.

[Sentinel lymph node mapping in non-small cell lung cancer]

The sentinel node (SN) concept is that lymphatic flux from a primary tumor initially flows into the SN. If this concept is correct, and metastasis is not found in a SN, it almost certainly that metastasis is not present in more distal lymph nodes. SN mapping and biopsy were developed as techniques for staging the lymphatic basin without the potential morbidity of lymph edema and nerve injury in cases of melanoma, or lymph edema of the arm in cases of breast cancer. Although there is also evidence of the existence of SN in non-small cell lung cancer (NSCLC), SN mapping is not widely used in the treatment of NSCLC. The potential benefit of SN mapping in NSCLC is enabling surgeons to know more precise staging of cancer. More sensitive techniques can be employed with a limited amount of tissue to detect micrometastasis. In addition, SN mapping can be applied to appropriate segmentectomy for NSCLC.

[Experience of twenty-one cases of tracheo-bronchoplasty]

Twenty-one cases of tracheo-bronchoplasty were performed in Akita University Hospital from 1997 to 2007. There are 14 cases of squamous cell carcinoma, 3 cases of adenocarcinoma, 2 cases of adenoid cystic carcinoma, 1 case of inflammatory tracheal stenosis, and 1 case of inflammatory bronchial stenosis. We performed 12 cases of right upper sleeve lobectomy, 4 cases of left upper sleeve lobectomy, 2 cases of left lower sleeve lobectomy, 1 case of right sleeve pneumonectomy, and 2 cases of tracheoplasty. Of 3 cases, we added sleeve resection of pulmonary artery. The ends of the bronchus are anastomosed end-to-end. The bronchial anastomotic suture was carried out peri-cartilaginously through all layers using an interrupted suture technique except for membranous portion. Membranous portion was sutured a continuous anastomotic technique. We use monofilament, absorbable suture material.

Sound spectrogram analysis in patients receiving Kawahara's surgical voice restoration for advanced carcinoma of the hypopharynx and cervical esophagus

Loss of voice after total laryngectomy is a major concern that has prompted much effort to develop methods of surgical voice restoration. In 1992, Kawahara described a tracheocolic shunt for voice restoration using a revascularized ileocolic graft. With this method, aspiration through the phonatory shunt is prevented by the ileocolic valve (Bauhin's valve), while vocalization is allowed. The purpose of this study was to use sound spectrogram analysis to evaluate voices surgically restored in that way. Between 2002 and 2005, 10 consecutive patients underwent laryngopharyngoesophagectomy with Kawahara's surgical voice restoration for advanced carcinoma of the hypopharynx and/or cervical esophagus at Akita University Hospital, Japan. We then used sound spectrography to analyze and compare the voices of patients receiving Kawahara's voice restoration, against healthy volunteers and patients who underwent the same surgery without voice restoration and spoke using an electronic larynx. We also evaluated the intelligibility of conversation and performed a listening test. The sound spectrograms showed that when produced by the electronic larynx, consonant sounds and voice frequencies below 300 Hz were not clearly recognized. By contrast, in patients who received Kawahara's surgical voice restoration, consonant and vowel sounds at frequencies above and below 300 Hz were clearly recognized. Although conversation was intelligible with both Kawahara's surgical voice restoration and the electronic device, listeners judged the voice produced by the former to be superior. Thus, the voice produced by Kawahara's surgical voice restoration is superior to that produced by the electronic larynx.

Extravascular Lung Water Measured Using Single Transpulmonary Thermodilution Reflects Perioperative Pulmonary Edema Induced by Esophagectomy

Pulmonary edema is the most frequent postoperative complication following esophagectomy for thoracic esophageal cancer. We enrolled 23 patients who underwent esophagectomy with extended lymph node dissection for thoracic esophageal cancer in a prospective observational clinical trial. We used the PiCCO device to measure extravascular lung water with the aim of determining whether it correlates with the respiratory index and whether it is predictive of pulmonary complications. Based on constant criteria, the tracheal tubes of 11 patients were removed on the morning of postoperative day 1 (extubation group), while 12 patients remained intubated (intubation group). These two groups significantly differed in that all patients in the extubation group recovered without any pulmonary complications, whereas 4 patients (33%) in the intubation group developed pulmonary complications. The extravascular lung water measured using PiCCO correlated significantly with the respiratory index. In the intubation group, both extravascular lung water and respiratory index were elevated 12 h after surgery and were even higher 24 h after surgery. The extravascular lung water measured using PiCCO reflects the level of postoperative pulmonary edema and predicts the pulmonary complications induced by esophagectomy with extended lymph node dissection.

[Survival after surgical resection for stage IV non-small cell lung cancer]

We analyzed 20 patients with stage IV non-small cell lung cancer operated from 1988 to 2003. Fourteen out of 20 were cases with pulmonary metastasis (pm2). The prognosis of patients with pm2 was better than that of those with distant organ metastasis. In pm2 patients, the survival rate of cases without lymph node metastases was higher than those with lymph node metastases. It is suggested that in cases of pm2 without lymph node metastases, surgical operation is possibly effective treatment of choice.

[Thymolipoma in association with myasthenia gravis; report of a case]

An 18-year-old man was admitted with easy fatigue and muscle weakness. A diagnosis of myasthenia gravis was made. Chest X-ray showed no mediastinal abnormality, however, chest computed tomography (CT) showed a soft tissue mass in the thymus. The patient underwent extended thymectomy and small tumor (2 x 2 x 2 cm) was resected. On histological examination the tumor proved to be a thymolipoma composed of mature adipose elements containing cords and nests of thymic tissue. Symptoms of myasthenia gravis were dramatically improved after the operation. This case is the 12th in the world literature in which a thymolipoma is associated with symptoms of myasthenia gravis.

Lack of monosynaptic corticomotoneuronal EPSPs in rats: disynaptic EPSPs mediated via reticulospinal neurons and polysynaptic EPSPs via segmental interneurons

In the rat, some findings have been taken to suggest the existence of monosynaptic corticomotoneuronal (CM) connections. Because this connection is believed to be largely responsible for the ability to make independent digit movements in primates and man, it has been inferred that the monosynaptic CM connection in the rat is likewise important for skilled prehension. Comparison of intra- and extracellular recordings from forelimb motoneurons in anesthetized rats, revealed no monosynaptic CM excitatory postsynaptic potentials (EPSPs). The fastest descending excitation in forelimb motoneurons was disynaptically mediated via a corticoreticulospinal pathway and slowly conducted excitation via corticospinal fibers and segmental interneurons. The findings stress the importance of di- and trisynaptic excitatory corticofugal pathways to forelimb motoneurons in the control of skillful digit movements.

A case of body stalk anomaly arising in the second baby of a triplet pregnancy after in-vitro fertilization and embryo transfer

We report a case of body stalk anomaly arising in the second baby of a triplet pregnancy after in-vitro fertilization and embryo transfer (IVF-ET). Body stalk anomaly or limb-body wall complex is a rare congenital anomaly with a series of similar clinical manifestations and poor prognosis. IVF-ET is an effective treatment for various types of infertility. We summarize and discuss herein the relation with the sequence of genesis for such malformations and multiple pregnancies after IVF-ET.

[Surgical treatment for pulmonary metastases from colorectal cancer]

Blalock first reported pulmonary resection for metastatic colorectal cancer in 1944. Since then, surgical resection of pulmonary metastases has been generally accepted as a standard therapeutic procedure in properly selected cases. Recently, the criteria of eligibility have been progressively expanded according to the development of radiological diagnosis using helical computed tomography (CT), widespread of minimum invasive video-assisted thoracic surgery. In this review summarized the surgical treatment of pulmonary metastases from colorectal cancer based on the recent literatures. Major areas of controversy remain with respect to the following aspects: prognostic factors (i.e., number of metastases, size of tumor, disease free interval, preoperative serum carcinoembryonic antigen level), procedure of operation (i.e., role of video-assisted thoracic surgery, lymphonode dissection), indication of surgical treatment on metastases both lung and liver, role of repeat thoracotomy for recurrence. For all above-mentioned points it appeared reasonable to try to the cooperative multicentric clinical prospective study.

Production of 5,8,11-eicosatrienoic acid by a delta5 and delta6 desaturation activity-enhanced mutant derived from a delta12 desaturation activity-defective mutant of Mortierella alpina 1S-4

Enhanced production of 5,8,11-eicosatrienoic acid (Mead acid, 20:3omega9) was attained with a mutant fungus, Mortierella alpina JT-180, derived from delta12 desaturation activity-defective and delta6 desaturation activity-enhanced M. alpina M209-7. Production of 20:3omega9 by JT-180 was 1.4 times greater than that of the parent strain M209-7. This is thought to be due to its enhanced Delta5 desaturation activity, which was 3.3 times higher than that of M209-7. In both strains, 78.5-80.4% of the total lipids comprised triacylglycerol (TG), and 76.6-79.0% of 20:3omega9 was present in TG. Comparing the fatty acid compositions among various lipid species, the highest percentages (24.1-37.6%) of 20:3omega9 in total lipids were found in phosphatidylcholine. For optimization of 20:3omega9 production by JT-180, a glucose concentration of 4% in the culture medium and shifting of the growth temperature from 28 degrees C to 20 degrees C on the 2nd day were shown to be effective. Under optimal conditions, 20:3omega9 production by JT-180 reached 1.92 g/l culture medium in a 10-l jar fermentor (corresponding to 81.5 mg/g dry mycelia and 18.3% of total fatty acids), which is greater than that reported previously from M209-7 (1.65 g/l).

Engineering cytochrome P450 BM-3 for oxidation of polycyclic aromatic hydrocarbons

Cytochrome P450 BM-3, a self-sufficient P450 enzyme from Bacillus megaterium that catalyzes the subterminal hydroxylation of long-chain fatty acids, has been engineered into a catalyst for the oxidation of polycyclic aromatic hydrocarbons. The activities of a triplet mutant (A74G/F87V/L188Q) towards naphthalene, fluorene, acenaphthene, acenaphthylene, and 9-methylanthracene were 160, 53, 109, 287, and 22/min, respectively. Compared with the activities of the wild type towards these polycyclic aromatic hydrocarbons, those of the mutant were improved by up to 4 orders of magnitude. The coupling efficiencies of the mutant towards naphthalene, fluorene, acenaphthene, acenaphthylene, and 9-methylanthracene were 11, 26, 5.4, 15, and 3.2%, respectively, which were also improved several to hundreds fold. The high activities of the mutant towards polycyclic aromatic hydrocarbons indicate the potential of engineering P450 BM-3 for the biodegradation of these compounds in the environment.

ABCA3 is a lamellar body membrane protein in human lung alveolar type II cells

The ABCA3 gene, of the ABCA subclass of ATP-binding cassette (ABC) transporters, is expressed exclusively in lung. We report here the cloning, molecular characterization, and distribution of human ABCA3 in the lung. Immunoblot analysis using the specific antibody reveals a 150-kDa protein in the crude membrane fraction of human lung. Immunohistochemical analyses of alveoli show that ABCA3 is expressed only in the type II cells expressing surfactant protein A. At the ultrastructural level, ABCA3 immunoreactivity was detected mostly at the limiting membrane of the lamellar bodies. Since members of the ABCA transporter family are known to be involved in transmembrane transport of endogenous lipids, our findings suggest that ABCA3 plays an important role in the formation of pulmonary surfactant in type II cells.

Residue size at position 87 of cytochrome P450 BM-3 determines its stereoselectivity in propylbenzene and 3-chlorostyrene oxidation

We report here oxidation of propylbenzene and 3-chlorostyrene by wild-type cytochrome P450 BM-3 with high turnover (479 nmol 1-phenyl-1-propanol/min/nmol P450 and 300 nmol 3-chlorostyrene oxide/min/nmol P450). Furthermore, the residue size at position 87 of P450 BM-3 was found to play critical roles in determining stereoselectivity in oxidation of propylbenzene and 3-chlorostyrene. Replacement of Phe87 with Val, Ala and Gly resulted in decreases in optical purity of produced (R)-(+)-1-phenyl-1-propanol from 90.0 to 37.4, 26.0 and -15.6% e.e., respectively, and in increases in those of produced (R)-(+)-3-chlorostyrene oxide from -61.0 to -38.0, 67.0 and 94.6% e.e., respectively.

Novel amidohydrolytic reactions in oxidative pyrimidine metabolism: analysis of the barbiturase reaction and discovery of a novel enzyme, ureidomalonase

Amidohydrolytic reactions in oxidative pyrimidine metabolism were investigated in detail. Barbiturase has been reported to catalyze the amidohydrolysis of barbituric acid to urea and malonic acid. However, purification of the enzyme revealed that it catalyzes the ring-opening of barbituric acid to ureidomalonic acid. The existence of a consecutive enzyme named ureidomalonase, which hydrolyzes ureidomalonic acid to urea and malonic acid, was also discovered during the purification of barbiturase.

Neural recognition molecule NB-2 of the contactin/F3 subgroup in rat: Specificity in neurite outgrowth-promoting activity and restricted expression in the brain regions

NB-2, a neural cell recognition molecule of the contactin/F3 subgroup, promoted neurite outgrowth of the cerebral cortical neurons but not the hippocampal neurons. NB-2 in rat became apparent after birth at protein level, reaching a maximum at postnatal day 14 in the cerebrum and postnatal day 3 in the cerebellum. NB-2 in the cerebellum declined abruptly thereafter. In situ hybridization demonstrated that NB-2 mRNA was highly expressed in regions implicated in the central auditory pathway, including the cochlear nuclei, superior olive, inferior colliculi, medial geniculate nuclei, and auditory cortex. In addition, a high level of NB-2 expression was observed in the accessory olfactory bulb, thalamic nuclei, facial nucleus, and inferior olive. By immunohistochemistry, intense immunoreactivity against NB-2 was also detected in the auditory pathway. Thus, NB-2 is expressed in highly restricted brain regions, including the auditory system, suggesting that it plays specific roles in the development and/or maturation of the regions.

Cancer of the gastric tube reconstructed through the posterior mediastinal route after radical surgery for esophageal cancer

Among 750 patients diagnosed with esophageal carcinoma in our department between 1972 and 1997, we reviewed our 10 cases in which cancer occurred within gastric tubes reconstructed through the posterior mediastinal route after radical surgery for esophageal cancer. The interval between esophagectomy and cancer onset in the reconstructed gastric tube was relatively long (mean interval: 72 months). Five of our 10 subjects had gastric tube cancer detected at follow-up endoscopy. Four underwent total or partial gastric tube resection with open thoracotomy using colonic or jejunal reconstruction; 3 underwent endoscopic resection. To the best of our knowledge, this is the first report on patients undergoing total resection of gastric tubes reconstructed through the posterior mediastinal route after esophagectomy and rereconstruction using the pedicled colon for the gastric tube cancer.

Purification, characterization, and gene cloning of purine nucleosidase from Ochrobactrum anthropi

A bacterium, Ochrobactrum anthropi, produced a large amount of a nucleosidase when cultivated with purine nucleosides. The nucleosidase was purified to homogeneity. The enzyme has a molecular weight of about 170,000 and consists of four identical subunits. It specifically catalyzes the irreversible N-riboside hydrolysis of purine nucleosides, the K(m) values being 11.8 to 56.3 microM. The optimal activity temperature and pH were 50 degrees C and pH 4.5 to 6.5, respectively. Pyrimidine nucleosides, purine and pyrimidine nucleotides, NAD, NADP, and nicotinamide mononucleotide are not hydrolyzed by the enzyme. The purine nucleoside hydrolyzing activity of the enzyme was inhibited (mixed inhibition) by pyrimidine nucleosides, with K(i) and K(i)' values of 0.455 to 11.2 microM. Metal ion chelators inhibited activity, and the addition of Zn(2+) or Co(2+) restored activity. A 1.5-kb DNA fragment, which contains the open reading frame encoding the nucleosidase, was cloned, sequenced, and expressed in Escherichia coli. The deduced 363-amino-acid sequence including a 22-residue leader peptide is in agreement with the enzyme molecular mass and the amino acid sequences of NH(2)-terminal and internal peptides, and the enzyme is homologous to known nucleosidases from protozoan parasites. The amino acid residues forming the catalytic site and involved in binding with metal ions are well conserved in these nucleosidases.

[A case of recurrent lung cancer successfully treated with vinorelbine and cisplatin]

A 56-year-old female underwent lobectomy with ND2a lymph node dissection for left lung cancer in April 1999. Histopathological examination demonstrated moderately differentiated adenocarcinoma (pT2N2M0, stage III A). She received one course of a combination of etoposide and cisplatin as adjuvant therapy, followed by oral intake of UFT. In November 1999, a left para-aortic lymph node recurrence was found. She received radiation therapy (total 60 Gy) to the mediastinum. In April 2000, new lung and left supraclavicular lymph node recurrences were found. She received three courses of vinorelbine 20 mg/m2 (days 1, 8) and cisplatin 80 mg/m2 (day 1) followed by radiation therapy (total 50.4 Gy) to the left supraclavicular lesion. After the chemotherapy, a complete response (CR) of all metastatic lesions was achieved. Adverse reactions were grade 1 alopecia, grade 2 nausea/vomiting, grade 3 neutropenia, hypochromia, and injection site reaction. The combination of vinorelbine and cisplatin is a useful regimen in non-small-cell lung cancer.

[A case of recurrent breast cancer successfully treated with docetaxel]

A 50-year-old female underwent mastectomy for left breast cancer in June, 1991. She received tamoxifen for 36 months and tegafur for 30 months as adjuvant therapy. In November 1997, liver, lung and para-aortic lymph node recurrences were found, and we treated her six times with docetaxel 60 mg. After the chemotherapy, a complete response (CR) of all metastatic lesions was achieved and her serum CA15-3 level was decreased. Adverse reactions were grade 4 neutropenia, grade 2 alopecia, fever, and grade 1 edema. She received medroxyprogesterone acetate after the chemotherapy and has been well without re-growth of any metastases for over eight months.

Conjugated linoleic acid accumulation via 10-hydroxy-12-octadecaenoic acid during microaerobic transformation of linoleic acid by Lactobacillus acidophilus

Specific isomers of conjugated linoleic acid (CLA), a fatty acid with potentially beneficial physiological and anticarcinogenic effects, were efficiently produced from linoleic acid by washed cells of Lactobacillus acidophilus AKU 1137 under microaerobic conditions, and the metabolic pathway of CLA production from linoleic acid is explained for the first time. The CLA isomers produced were identified as cis-9, trans-11- or trans-9, cis-11-octadecadienoic acid and trans-9, trans-11-octadecadienoic acid. Preceding the production of CLA, hydroxy fatty acids identified as 10-hydroxy-cis-12-octadecaenoic acid and 10-hydroxy-trans-12-octadecaenoic acid had accumulated. The isolated 10-hydroxy-cis-12-octadecaenoic acid was transformed into CLA during incubation with washed cells of L. acidophilus, suggesting that this hydroxy fatty acid is one of the intermediates of CLA production from linoleic acid. The washed cells of L. acidophilus producing high levels of CLA were obtained by cultivation in a medium containing linoleic acid, indicating that the enzyme system for CLA production is induced by linoleic acid. After 4 days of reaction with these washed cells, more than 95% of the added linoleic acid (5 mg/ml) was transformed into CLA, and the CLA content in total fatty acids recovered exceeded 80% (wt/wt). Almost all of the CLA produced was in the cells or was associated with the cells as free fatty acid.

Critical role of the residue size at position 87 in H2O2- dependent substrate hydroxylation activity and H2O2 inactivation of cytochrome P450BM-3

Replacement of phenylalanine 87 with alanine or glycine (mutant F87A or F87G) greatly increased the H2O2-supported substrate hydroxylation activity of cytochrome P450BM-3, whose original H2O2-supported activity is hardly detectable. On the other hand, replacement of phenylalanine 87 with valine (mutant F87V) did not. In the oxidation of p-nitrophenoxydodecanoic acid (12-pNCA), the turnover numbers of the mutant F87A in the presence of NADPH and O2, or H2O2 were 493 and 162 nmol/min/nmol, respectively. The H2O2-supported F87A hydroxylation activity was further confirmed with free fatty acids as substrates. Moreover, the stability of F87A in H2O2 solutions also largely increased. The order of the stability of the wild type (WT), F87A, and their substrate (12-pNCA)-binding complexes in H2O2 solutions listed from high to low was F87A, WT, F87A substrate-binding complex, and WT substrate-binding complex. We propose that the free space size in the vicinity of the heme iron significantly influences P450BM-3 H2O2-supported activity and H2O2 inactivation.

Short-term complications and long-term results of expansive open-door laminoplasty for cervical stenotic myelopathy

BACKGROUND CONTEXT

Laminoplasty has been reported to achieve good operative results for treatment of cervical stenotic myelopathy. However, long-term results and prognostic factors have not been well documented. Among postoperative complications, weakness of the shoulder girdle muscles has been reported as a particular complication of laminoplasty, but the cause is still poorly understood.

PURPOSE

Our aim was to clarify the short-term complications and long-term operative results after unilateral open-door laminoplasty and to identify the predictors for operative outcome.

STUDY DESIGN

We retrospectively reviewed short-term complications and long-term operative results associated with cervical stenotic myelopathy treated by unilateral open-door laminoplasty.

PATIENT SAMPLE

There were 162 men and 42 women with an average age of 57 years who were treated by unilateral open-door laminoplasty in the two institutions. Pathogenesis of myelopathy was cervical spondylosis in 88 patients, cervical disk herniation with a narrow spinal canal in 10, and ossification of the posterior longitudinal ligament in 106.

OUTCOME MEASURES

Postoperative complications and their outcomes were examined clinically in 204 patients, and causes of motor paresis were sought with postoperative computed tomography after myelography. Postoperative improvement of clinical symptoms was assessed by recovery rate calculated with the scores of the Japanese Orthopaedic Scoring System in 80 patients.

METHODS

The occurrence rate of short-term postoperative complications, causes of motor paresis, and their outcomes were reviewed in 204 patients. Clinical condition was assessed with the Japanese Orthopaedic Scoring System, recovery rate was calculated with the score, and prognostic factors for outcome were studied in 80 patients who were followed up for 5 years or longer (average, 8 years; range, 5-17 years).

RESULTS

Occurrence rate of complications, such as muscle weakness, deep infection, closure of opened laminae, and others, was 10.8%. Muscle weakness was observed in 7.8% of the patients. However, this rate decreased in recent years. The cause of motor paresis is not known with certainty, but it may be secondary to operative trauma, posterior shift of the spinal cord, or to displacement of the lamina in the hinge side. Recovery rate of clinical symptoms was 62.1% at the final follow-up. Rates were 63.6% for cervical spondylosis, 87.1% for cervical disk herniation, and 61.3% for ossification of the posterior longitudinal ligament. There was no significant difference between pathologies. Patient age younger than 60 years at the time of operation and less than 1 year's duration of symptoms before surgery were significantly associated with recovery rate of clinical symptoms. Recovery rate was not correlated with either preoperative function judged by the Japanese Orthopaedic Association score or spinal sagittal diameter.

CONCLUSIONS

The main cause of postoperative motor paresis of upper extremities is thought to be operative trauma, resulting from such procedures as air-drill and Kerrison rongeur handling. Short-term complications may decrease with the use of nontraumatic procedures. Better operative outcomes may be achieved with careful operative procedures and early operative treatment in the patients with myelopathy.

Cisplatin induces fas expression in esophageal cancer cell lines and enhanced cytotoxicity in combination with LAK cells

OBJECTIVE

To establish a new therapeutic approach for the treatment of esophageal cancer, we investigated an alternative mechanism of immunotherapy for sensitizing target cells to effector cells.

METHODS

Six human esophageal cancer cell lines were used. The expression of Fas antigen on tumor cells was determined by flow cytometry. The cytotoxic effect of cis-dichlorodiammineplatinum (CDDP) and anti-Fas antibody was evaluated using an MTT assay. The cytotoxic activity of LAK cells was measured by a (51)Cr release assay.

RESULTS

Five out of six esophageal cancer cell lines expressed Fas antigen at various levels (26.2-61.5%), and Fas expression increased after CDDP treatment. The antitumor effect of anti-Fas antibody on the esophageal cancer cell line and the antitumor effect of LAK cells activated by IL-2 were enhanced by pretreatment with CDDP. After concanamycin A treatment to specifically evaluate Fas-dependent cytotoxicity, LAK cells expressing Fas ligand killed only Fas-positive cells, but not Fas-negative cells. An anti-Fas neutralizing antibody inhibited this cytotoxicity. DNA fragmentation was shown in a cell line that was treated with CDDP and anti-Fas antibody, and also in the targeted esophageal cancer cell line cocultured with LAK cells.

CONCLUSION

Our results suggest a potential clinical application of CDDP as a Fas inducer to make esophageal tumors susceptible to Fas antigen and LAK cytotoxicity.