Ferredoxin-dependent redox system of a thermoacidophilic archaeon, Sulfolobus sp. strain 7. Purification and characterization of a novel reduced ferredoxin-reoxidizing iron-sulfur flavoprotein

To elucidate the ferredoxin-dependent redox system of the thermoacidophilic, aerobic archaeon Sulfolobus sp. strain 7, a novel FeS flavoprotein, which can reoxidize the reduced 7Fe ferredoxin in vitro, has been purified and characterized (designated as IFP) using the cognate 7Fe ferredoxin and 2-oxoacid:ferredoxin oxidoreductase, a key enzyme of the archaeal tricarboxylic acid cycle. IFP consists of three non-identical subunits with apparent molecular masses of 87, 32, and 22 kDa, respectively, and contains at least two FMN (Em, 6.8 = -57 mV) and two plant-ferredoxin-type [2Fe-2S]2+,1+ clusters (Em, 6.8 = -260 mV)/alpha 2 beta 2 gamma 2 structure. Both FeS and flavin centers of IFP are slowly but fully reduced by the enzymatically reduced cognate ferredoxin under anaerobic conditions at 50 degrees C, but not by NAD(P)H. Thus, the ferredoxin-dependent redox system of Sulfolobus sp. strain 7 is tentatively proposed as follows: 2-oxoacid:ferredoxin oxidoreductase (thiamine pyrophosphate and [4Fe-4S] cluster)-->ferredoxin-->IFP ([2Fe-2S] cluster-->FMN).

Involvement of benzodiazepine/GABA-A receptor complex in ethanol-induced state-dependent learning in rats

State-dependent learning (SDL) induced by ethanol (EtOH) was investigated on the step-through passive avoidance task in rats. Pretraining injection of EtOH dose-dependently reduced step-through latency in the test session 24 h after the training. Injection of EtOH (1.0 g/kg) before both the training and test sessions, however, failed to reduce the latency. These results show that EtOH produces SDL. The failure of learning performance in SDL (dissociation in SDL) induced by EtOH was blocked by bicuculline, Ro15-4513 and picrotoxin injected before the training session. The success of learning performance in SDL (non-dissociation in SDL) induced by EtOH was also blocked by bicuculline, Ro15-4513 and picrotoxin injected before the test session. The antagonism of Ro15-4513 against EtOH was blocked by flumazenil. In the substitution test, pretest injection of EtOH produced non-dissociation in SDL in the both of pretraining diazepam-and muscimol-treated rats. On the other hand, neither pretest injection of diazepam nor muscimol produced non-dissociation in the pretraining EtOH-treated rats: asymmetrical cross-substitution between EtOH and diazepam and between EtOH and muscimol was observed. These results suggest that the EtOH-induced SDL is partially mediated by the benzodiazepine (BDZ)/GABA-A receptor complex.

Canine bullous pemphigoid (BP): identification of the 180-kd canine BP antigen by circulating autoantibodies

Human bullous pemphigoid (BP) is an immune-mediated blistering disease characterized by autoantibodies against BP antigens (230/180 kd), which are constitutive glycoproteins of hemidesmosomes found in basal keratinocytes. Blistering diseases similar to human BP have been reported in dogs. IgG deposits at the basement membrane zone (BMZ) are a common feature of canine BP. Although circulating anti-BMZ IgG autoantibodies have been demonstrated in some cases of canine BP, the specific skin protein targeted by these autoantibodies has not been identified. In this study, we characterized the antigenic target of the autoantibodies in the serum from a 3-year-old castrated male Pit Bull Terrier with BP. Direct immunofluorescence of the patient's skin demonstrated IgG deposits at the dermal-epidermal junction. Indirect immunofluorescence demonstrated autoantibodies in the patient's serum that stained the epidermal roof of salt-split canine skin and left the dermal floor unstained. These serum autoantibodies did not stain normal intact dog skin but labeled intact bovine tongue. Direct immunoelectron microscopy of the dog's skin revealed IgG deposits within the hemidesmosomes of the basal keratinocytes. Western immunoblotting experiments showed that canine keratinocytes express both the 230-kd and 180-kd bullous pemphigoid antigens, and the autoantibodies from the patient's serum recognized the 180-kd bullous pemphigoid antigen in proteins extracted from canine and human keratinocytes. Canine BP has many parallel features with human BP including similar immune deposition of IgG within hemidesmosomes and a hemidesmosome-associated 180-kd glycoprotein target for circulating autoantibodies.

[Evaluation of preoperative blood preparation and blood consumption for implementation of type and screen and maximum surgical blood order schedule]

We analyzed preoperative blood preparation and intraoperative blood transfusion in Kagawa Prefectural Central Hospital and evaluated the effectiveness of maximum surgical blood order schedule (MSBOS) and Type and Screen (T&S). Forty seven kinds of surgery were performed on 1,283 cases from May, 1991 to April, 1992. Transfusion was performed in 179 cases of them. All of 1,884 units of blood that had been prepared, were crossmatched and 1,078 of them were actually transfused. The Crossmatched to Transfused ratio (C/T ratio) was 1.71. If we adopted MSBOS and T&S in 13 elective surgery, 766 units of blood and labour work for preoperative blood preparation could have been saved. MSBOS and T&S are beneficial for efficient usage of blood transfusion in surgery.

Injection of ethanolamine oleate into a segmental portal branch for pharmacologic hepatic segmentectomy in dogs

RATIONALE AND OBJECTIVES

Currently available treatments for hepatocellular carcinoma are not satisfactory in terms of recurrence rates. In this study, we injected ethanolamine oleate (EO) into a portal branch in an attempt to cause necrosis of a liver segment in which hepatocellular carcinoma might be located.

METHODS

Nine dogs received EO injections via a balloon catheter into a segmental portal branch of the liver.

RESULTS

Immediately after injection, 80-100% of the liver cells in the EO-injected segment underwent coagulative necrosis. After 1 week, the EO-injected segment had become completely necrotic in two dogs. Only a few viable hepatocytes were still observed around the arteries and beneath the liver capsule in another dog. No pathologic changes were observed in the lungs, kidneys, or heart of any dog. There was a correlation between the EO dosages and the volume of the EO-injected liver tissue.

CONCLUSION

EO injection into a portal branch results in the pharmacologic destruction of the corresponding liver segment. This procedure may be beneficial in the treatment of hepatic malignancies.

Identification of a cis-regulatory region of a gene in Arabidopsis thaliana whose induction by dehydration is mediated by abscisic acid and requires protein synthesis

In Arabidopsis thaliana, the induction of a dehydration-responsive gene, rd22, is mediated by abscisic acid (ABA) but the gene does not include any sequence corresponding to the consensus ABA-responsive element (ABRE), RYACGTGGYR, in its promoter region. The cis-regulatory region of the rd22 promoter was identified by monitoring the expression of beta-glucuronidase (GUS) activity in leaves of transgenic tobacco plants transformed with chimeric gene fusions constructed between 5'-deleted promoters of rd22 and the coding region of the GUS reporter gene. A 67-bp nucleotide fragment corresponding to positions -207 to -141 of the rd22 promoter conferred responsiveness to dehydration and ABA on a non-responsive promoter. The 67-bp fragment contains the sequences of the recognition sites for some transcription factors, such as MYC, MYB, and GT-1. The fact that accumulation of rd22 mRNA requires protein synthesis raises the possibility that the expression of rd22 might be regulated by one of these trans-acting protein factors whose de novo synthesis is induced by dehydration or ABA. Although the structure of the RD22 protein is very similar to that of a non-storage seed protein, USP, of Vicia faba, the expression of the GUS gene driven by the rd22 promoter in non-stressed transgenic Arabidopsis plants was found mainly in flowers and bolted stems rather than in seeds.

[Static characteristics of accommodation on the relationship between accommodative resting position and viewing distance]

The steady-state accommodation of subjects during a 15 min visual task was measured in real time by an infrared optometer to investigate the relationship between accommodative resting position and the effect of viewing distance. When the subjects were loaded at 50 cm (closer than their resting state), the steady-state accommodation showed an inward shift which was enhanced when computation was done. On the contrary, when they worked outside their resting position-2m viewing distance-, an outward shift of steady-state accommodation was seen in the control group who reacted only to the visual objects displayed. For the mental task group this was not evident. It appears that the steady-state accommodation is different between the cases of visual stimuli given inside and outside the resting position.

Messenger RNA for the guanine nucleotide-binding regulatory protein (G protein) is reduced in the acute ischemic myocardium

It has been reported that the function of the guanine-binding regulatory protein (G protein), especially the alpha subunit of the stimulatory G protein (Gs alpha), in myocardium is decreased with acute ischemia. However, it is unclear whether this decrease is due to transcriptional or post-transcriptional changes. Moreover, no studies have examined the distribution of G protein mRNA in ischemic myocardium using in situ hybridization. The purpose of this study was to explore alterations in mRNA of G proteins (Gs and Gi) in ischemic hearts using in situ hybridization. We measured the levels of mRNA for Gs alpha and Gi alpha in ischemic and non-ischemic myocardium by in situ hybridization using a radioisotope imaging system. We compare these mRNA levels in ischemic and non-ischemic myocardium with Northern blot analysis and the protein levels of G proteins by Western blot analysis. The mRNA for Gs alpha and Gi alpha was distributed diffusely in normal hearts. Levels of mRNA detected by in situ hybridization were substantially reduced by acute ischemia, and these results were confirmed by Northern and Western blot analysis. These results suggest that decreased levels of mRNA and protein for G proteins may underlie the impaired function of the receptor--G protein--adenylate cyclase system in ischemic myocardium. In addition, quantitative evaluation of mRNA is possible by in situ hybridization and correlates well with Northern analysis.

Sulredoxin: a novel iron-sulfur protein of the thermoacidophilic archaeon Sulfolobus sp. strain 7 with a Rieske-type [2Fe-2S] center

A novel pink [2Fe-2S] protein has been purified from the cytosol fraction of the thermoacidophilic archaeon Sulfolobus sp. strain 7 (originally named Sulfolobus acidocaldarius 7) and called "sulredoxin." Its absorption, circular dichroism, and electron paramagnetic resonance spectra suggest the presence of a Rieske-type [2Fe-2S] cluster (g-factors of 2.01, 1.91, and 1.79; average g-factor [gav] = 1.90) which is remarkably similar to that of Thermus thermophilus respiratory Rieske FeS protein (J. A. Fee, K. L. Findling, T. Yoshida, R. Hille, G. E. Tarr, D. O. Hearshen, W. R. Dunham, E. P. Day, T. A. Kent, and E. Münck, J. Biol. Chem. 259:124-133, 1984) and distinctively different from those of the plant-type ferredoxins (gav = 1.96). Sulredoxin, which is the first Rieske-type [2Fe-2S] protein isolated from an archaeal species, does not function as an electron acceptor of the cognate 2-oxoacid:ferredoxin oxidoreductase. Whether sulredoxin is derived from the archaeal membrane-bound respiratory Rieske-type FeS center (gy = 1.91) is the subject of further investigation.

Unaltered size of right ventricular infarct in dogs with right ventricular hypertrophy induced by pressure overload

We investigated whether right ventricular infarct size is increased in the hypertrophied right ventricle. In dogs, we produced chronic pressure overload-induced right ventricular hypertrophy (RVH) and acute pulmonary stenosis (APS) with a similar right ventricular systolic pressure to RVH. Then, in an open-chest model, right coronary artery occlusion for 4 h followed by 1 h of reperfusion was performed in animals with RVH or APS or in controls. Regional myocardial blood flow was measured with nonradioactive colored microspheres. Compared with the control group, regional myocardial oxygen consumption in the right ventricle was increased in the APS but not in the RVH group. The risk area and collateral blood flow were comparable in the three groups. However, the infarct size relative to risk area was increased in the APS group (42.3 +/- 4.9%), but that in the RVH group (21.1 +/- 4.4%) was not different from controls (26.1 +/- 4.2%). Thus right ventricular infarction in the heart with RVH was not increased compared with the normal heart.

Basal cell tumor in a Japanese macaque (Macaca fuscata)

A rare case of basal cell tumor of the skin in a wild-caught female Japanese macaque (Macaca fuscata) was studied. Tumor growth, which was composed of cells resembling basal cells, was observed in the dermis and subcutis and showed a mixture of ribbon, solid, glandular, and cystic patterns. The tumor was separated from surrounding normal tissue by a compressed zone of fibrous connective tissue. The nuclei were round and hyperchromatic and possessed a single centrally located nucleolus. Mitotic figures were common. Immunohistochemically, a positive reaction for epithelial membrane antigen, keratin, and cytokeratin AE3 was evident. Electron microscopic examination revealed a small number of tonofilaments in the cytoplasm.

Clinical pilot study on high-dose intraarterial chemotherapy with direct hemoperfusion under hepatic venous isolation in patients with advanced hepatocellular carcinoma

BACKGROUND

We recently developed a novel system of direct hemoperfusion under hepatic venous isolation in an attempt to achieve high-dose intraarterial chemotherapy for patients with malignant liver tumors. We report here the results of treatment of these patients with advanced hepatocellular carcinoma.

METHODS

Adriamycin (100 to 150 mg/m2) was administered into the hepatic artery of 15 patients, under conditions of extracorporeal drug elimination by direct hemoperfusion under hepatic venous isolation. Hepatic venous isolation was accomplished mainly by the double-balloon technique with an occlusion catheter and a balloon catheter. The isolated hepatic venous blood was filtered by direct hemoperfusion and pumped to the left axillary vein.

RESULTS

During 5 minutes of adriamycin infusion, the mean drug extraction ratios of the direct hemoperfusion filters were 91% +/- 9% (mean +/- SD). The amount of drug removed by the system was 26.4% +/- 16.0% of the amount of drug administered. Two patients died, one of necrotizing pancreatitis and the other of hepatic arterial thrombosis. Both deaths were related directly to the hepatic arterial catheter. Other side effects included hemolysis related to the system of hemoperfusion (87%), chemical hepatitis (80%), leukopenia less than 3000/mm3 (67%), alopecia (33%), and nausea and vomiting (20%). Nine (64%) of 14 evaluable patients had objective tumor responses, with a median duration of response of 6.2 months.

CONCLUSIONS

This approach offers an effective therapeutic option for patients with advanced hepatocellular carcinoma.

Analysis of recombination junctions in extrachromosomal circular DNA obtained by in-gel competitive reassociation

Essentially all eukaryotic cells contain circular extrachromosomal DNA as a result of excision from the chromosomes. To obtain insight into the nature of recombination associated with the occurrence of such DNA species and its biological significance, we analyzed a library enriched in recombination junctions which was constructed by a novel DNA subtraction technique; in-gel competitive reassociation (IGCR). Furthermore, we also introduced inverse PCR to characterize chromosomal DNA fragments containing the recombination junctions. At least 45% of the clones in the library constructed by the IGCR procedure comprised DNA with recombination junctions. Nucleotide sequence analysis of the recombination junctions indicated that three of four extrachromosomal DNAs thus analyzed were produced through recombination between sequences with a 3-5 bp homology in the chromosomes. One extrachromosomal DNA was apparently generated through non-homologous recombination, possibly by end-to-end joining. These results have demonstrated the usefulness of IGCR in concentrating recombination junctions, which provide the most direct evidence for the mechanism of the recombinational events involved, from highly complex genomes.

[Neuron specific enolase-producing IgD multiple myeloma with high serum amylase activity]

A 68-year-old man who was admitted to our hospital because of general fatigue and anorexia. He was diagnosed as suffering from neuron specific enolase (NSE)-producing IgD-lambda type multiple myeloma with high activity of serum amylase, based on the detection of monoclonal IgD-lambda M-protein in the serum and urine, markedly high activities of salivary-type amylase and NSE in the serum, and immunohistochemical evidence of NSE and IgD in the myeloma cells. After two courses of alpha-IFN and VMCP chemotherapy, serum IgD, amylase and NSE decreased to normal levels. These observations indicate that NSE was ectopically produced by myeloma cells.

Histopathologic features of naturally occurring hepatozoonosis in wild martens (Martes melampus) in Japan

Nodular lesions containing Hepatozoon sp. schizonts or merozoite-gametocytes were found in the tissues of 67 (96%) of 70 wild-caught martens (Martes melampus) examined in Gifu, Japan, 1991 and 1992. The heart was the most commonly parasitized organ (96%), followed by the perirenal adipose tissue (36%); the diaphragm, mesentery, tongue, omentum and perisplenic adipose tissue generally had a prevalence of 10 to 15%. In the heart, two types of nodular lesions were differentiated based on developmental stages: nodules containing schizonts and nodules consisting of an accumulation of phagocytes containing merozoites or gamonts. Under electron microscopy, mature schizonts contained membrane-bound merozoites with a single nucleus and small scattered electron-dense cytoplasmic granules in the schizont nodules; the merozoites and gamonts were engulfed in a phagosome-like vacuole of phagocytes with the nucleus compressed to one side due to the parasite in the merozoite-gamont nodule.

The effects of antianginal drugs on energy expenditure during exercise in normal subjects

The respiratory quotient (RQ = VCO2/VO2) provides important information (ie, the ratio of carbohydrate to fat utilization) concerning energy expenditure. We studied the effects of various antianginal drugs on energy expenditure during steady-state aerobic exercise in 9 healthy adult men. The drugs used were propranolol (a non-selective beta-blocker), metoprolol (a beta-1 selective blocker), amosulalol (an alpha- and beta-blocker), nicardipine (a calcium antagonist) and isosorbide dinitrate. Each drug was administered for 2 weeks, followed by a 2-week washout period. VO2, VCO2 and RQ were measured with an expired gas analyzer during treadmill exercise tests before and during the administration of each drug. Two protocols of constant-load exercise were performed: Protocol 1 lasted for 10 min at a speed of 5.5 km/h and a grade of 0%, (at a level of about 30% peak VO2), while Protocol 2 lasted for 10 min at a speed of 7 km/h and a grade of 0%, (at a level of about 40% peak VO2). RQ during exercise was significantly increased and VO2 was decreased after propranolol, metoprolol and amosulalol (P < 0.05). Neither nicardipine nor isosorbide dinitrate produced significant changes in these values. These data suggest that propranolol, metoprolol and amosulalol increase the efficiency of energy expenditure during ordinary physical activity by increasing the utilization of carbohydrate and by decreasing the utilization of fat.

Molecular characteristics of porcine thymus histone H1 variants

We constructed an assay system to measure the annealing activity that is one of the functional features of nuclear proteins, using ssDNAs derived from M13 phage recombinants which contained a complementary 406-bp portion each. Histone H1 variants were purified from porcine thymus by separation of chromatin, extraction with 5% perchloric acid, and reversed-phase HPLC. Three types of histone H1 variants were found by analysis of amino acid composition and on SDS-PAGE. All of these could promote the annealing. According to Hill's analysis all had similar numbers of binding sites to DNA strands but dissociation constants and annealing activity were different. The number of binding sites, dissociation constants, and annealing activity were changed by dephosphorylation of histone H1 variants. This result suggests that histone H1 variants have different affinities for DNA molecules and ssDNA-annealing activity, which is regulated by phosphorylation.

[Cryoglobulinemia]

Cryoglobulins are proteins that precipitate when cooled and dissolve when heated. Cryoglobulinemia may be classified into Type I (monoclonal), Type II (mixed), and Type III (polyclonal). About 5 to 10% of myeloma proteins and 7 to 20% of primary macroglobulinemia proteins are cryoprecipitable (Type I cryoglobulin), and more than half of these have no symptoms attributable to cryoglobulin nature of their M-component. The most common symptoms of Type I cryoglobulinemia include Raynaud's phenomenon, necrosis of the toes or legs, vascular purpura, and urticaria. In Type I cryoglobulinemia due to plasma cell dyscrasias, treatment is directed primarily at the underlying disease. Plasmapheresis and cryofiltration may be helpful particularly when this can be combined with effective chemotherapy.

Terpentecin and ECT4B, new family of topoisomerase II targeting antitumor antibiotics produced by Streptomyces: producing organism, fermentation and large scale purification

Terpentecin and UCT4B are new family of antitumor antibiotics with topoisomerase II mediated DNA cleavage activity. Based on the taxonomic studies, the producing strain S-464 was identified as Streptomyces sp. This strain is different from Kitasatosporia griseola which had been identified as the terpentecin-producing strain in 1988. Fermentation studies showed that natural nitrogen sources supported higher titer of terpentecin, and the synthetic medium with inorganic nitrogen sources supported selective production of UCT4B. An improved isolation method was developed for the large scale purification of terpentecin.

Subclinical renal oxalosis in wild-caught Japanese macaques (Macaca fuscata)

Various degrees of crystal deposition were found in the kidneys of 12 out of 59 Japanese macaques (Macaca fuscata) caught in the wild in Gifu, Japan. The needle- or rod-shaped crystals, which were radially arranged and occurred in the lumen and epithelium of the renal (mainly the proximal) tubules, were birefringent under polarized light. They stained with alizarin red S at a pH of 7.0 but not 4.2, and were identified as calcium oxalate. The morphological features of the renal lesions were similar to those previously reported in oxalate poisoning, and it was believed that the macaques ingested the oxalate in plants.

[Evaluation of sinoatrial conduction by the initial potential of the P wave signal-averaged electrocardiogram]

We investigated whether sinoatrial conduction can be evaluated by the initial potential (IP) on the P wave signal-averaged electrocardiogram (PSAE). We studied 61 patients who underwent electrophysiologic study. Programmed stimulation was performed to obtain the sinoatrial conduction time (SACT) and the maximal sinus node recovery time (SRTmax). The root mean square voltages for the initial 10 and 20 msec of the filtered P waves (IP10 and IP20) were calculated based on PSAE. The association between IP10 and IP20 with SACT or SRTmax was analyzed by linear regression analysis. The reduction of IP10 or IP20 was negatively correlated with the prolongation of SACT, but was not correlated with the prolongation of SRTmax. Our findings showed that IP on the PSAE can be used to estimate the status of sinoatrial conduction.