Carboxyl-terminal processing protease for the D1 precursor protein: cloning and sequencing of the spinach cDNA

A previous study has demonstrated that the carboxyl-terminal (C-terminal) processing protease in spinach for the D1 precursor protein (pDl) of the photosystem II reaction center is a monomeric protein of about 45 kDa. Based on the amino acid sequence data of the purified protease, a cDNA clone encoding the enzyme has been identified and sequenced, from a spinach green leaf cDNA library. In order to determine the 5' end of the transcript, the rapid amplification of cDNA end (5'-RACE) technique was applied. By these analyses, the full-length transcript was established to consist of 1906 nucleotides and a poly(A) tail, containing an open reading frame (ORF) corresponding to a protein with 539 amino acid residues. By comparing the amino acid sequence of the purified protease with that deduced from nucleotide sequence of the cDNA clones, the enzyme was shown to be furnished with an extra amino-terminal extension characteristic of both a transit peptide and a signal sequence. This suggests that the protease is synthesized in the cytosol and translocated into the lumenal space of thylakoids. The mature part of the enzyme consists of 389 amino acid residues and exhibits a significant sequence homology with two groups of proteins as demonstrated by a computer homology search, i.e. (1) the deduced sequence of a protein proposed to be the C-terminal processing protease for pD1 in Synechocystis sp. PCC 6803, based on genetic experiments and (2) proteases for C-terminal cleavage identified in Escherichia coli and Bartonella bacilliformis.

The first case of insulin-dependent diabetes mellitus with prominent spurious hyperglucagonemia due to interference of immunoglobulin G in glucagon radioimmunoassay (OAL-123) system

A 51-year-old male was admitted to our hospital because of diabetic ketoacidosis. His symptoms were promptly improved with intensive insulin therapy, but his plasma glucagon immunoreactivity measured by the OAL-123 radioimmunoassay (RIA) system showed persistently high values (3,090-3,210 pg/ml). A computed tomographic scan, abdominal angiography and endoscopic examination of his gastrointestinal tract showed no evidence of glucagonoma. After removing the immunoglobulin fraction from the plasma, his immunoreactive plasma glucagon level returned to normal. Moreover, the immunoglobulin G fraction purified from the patient's plasma inhibited the binding of [125I]glucagon to rabbit antiglucagon antiserum, OAL-123. Dot-blot analysis demonstrated that the immunoglobulin G of this patient cross-reacted against OAL-123. Therefore, it was considered that the prominent hyperglucagonemia in this patient was due to the presence of IgG, which interfered with the measurement of plasma-immunoreactive glucagon.

Molecular cloning and sequence analysis of the gene encoding the H2O-forming NADH oxidase from Streptococcus mutans

To discover the molecular properties of two distinct NADH oxidases, corresponding to H2O2-forming oxidase (NOX-1) and H2O-forming oxidase (NOX-2) induced in Streptococcus mutans, for the first step we had cloned and sequenced the nox-1 gene encoding NOX-1. In this paper, a nox-2 gene encoding NOX-2 from S. mutans was cloned, and the nucleotides sequenced. The nox-2 gene comprises 1371 base-pairs, encoding a polypeptide of 457 amino acid residues. The deduced relative molecular mass (M(r) = 49919) agreed with the previous value obtained from the purified NOX-2 protein. The nox-2 gene was expressed in Escherichia coli using its own promoter. Alignment of the NOX-2 protein sequence with that of the NOX-1 showed that the proteins do not significantly resemble each other. Comparisons with the NADH oxidase from Streptococcus faecalis 10C1 yield identities of 41%. The redox-active cysteine in the enzyme from S. faecalis was found to correspond to Cys 44 in the NOX-2.

Recurrent laryngeal papillomatosis developing into laryngeal carcinoma with human papilloma virus (HPV) type 18: a case report

We report a case of recurrent laryngeal papillomatosis which developed into laryngeal squamous cell carcinoma 11 years after the first diagnosis. Interestingly, we could identify HPV type 18 DNA in the carcinoma tissue using the polymerase chain reaction (PCR). Other known risk factors of irradiation, smoking, exposure to chemical agents, or a hereditary tendency to malignant tumours were not present in this case. Our finding suggests that HPV type 18 is another aetiological agent for laryngeal carcinoma.

Seroepidemiological study of human herpesvirus-6 and -7 in children of different ages and detection of these two viruses in throat swabs by polymerase chain reaction

The presence of human herpesvirus 6 (HHV-6) and human herpesvirus 7 (HHV-7) in throat swabs of 62 children of different age groups (group I, ages 0-5 month; group II, ages 6-11 months, group III, ages 12-23 months, group IV, age 2-8 years) and 28 adults was detected by polymerase chain reaction. The detection rate of HHV-6 DNA was the highest (87%) in children aged 1-year-old and decreased with age, whereas the detection rate of HHV-7 increased with age and reached a maximum in adults. HHV-6B was detected in almost all samples except for two children who secreted only HHV-6A. When the antibody prevalence was determined in the four groups of children, HHV-6 antibody was detected in 8/12 (66.7%), 10/12 (83.3%), 15/16 (93.8%), and 13/14 (92.9%), respectively. Antibody to HHV-7 in these groups was detected in 6/12 (50.0%), 4/12 (33.3%), 12/16 (75.0%), and 13/14 (92.9%), respectively. Detection of HHV-6 DNA in throat swabs of triplets who had the sequential onset of exanthem subitum was attempted by using samples sequentially collected from these children after the onset of the disease in the first patient. HHV-6 DNA with high copy numbers was detectable during the acute and convalescent phases of the disease in all patients, but no DNA was detected in samples collected before the onset of disease.

H-NMR study of temperature-induced structure alteration at the active site of horse heart cytochrome c

The molecular structure of the active site of horse heart met-cyano cytochrome c, as a function of temperature, has been investigated using 1H-NMR. A temperature dependence study of the NMR spectra revealed that one heme methyl proton resonance exhibits anti-Curie behavior, i.e., the hyperfine shift increases with increasing temperature. Analyses of the average heme methyl proton hyperfine shift and the proximal His imidazole proton resonances indicated that the iron-His bonding interaction in this protein is essentially independent of temperature. Since such an anomalous temperature dependence of the heme methyl proton resonance disappears in met-cyano complex of a heme peptide prepared by enzymatic degradation of the protein [Smith, M. and McLendon, G. (1981) J. Am. Chem. Soc. 103, 4912-4921], the anti-Curie behavior observed for the heme methyl proton resonance in met-cyano cytochrome c is attributed to a rotational displacement of the heme about the iron-His bond relative to the protein moiety due to a temperature-dependent conformational alteration of the heme-protein linkage. Such rotational mobility of heme at the active site of a protein may be responsible for the anomalous temperature dependence of heme methyl proton hyperfine shifts reported for many c-type ferri cytochromes.

Development in vitro of preimplantation embryos from 55 mouse strains

Mouse pronuclear embryos were obtained by in vitro fertilization with oocytes of 55 strains of immature females by gonadotrophin-induced ovulation and epididymal sperm of Slc:ICR strain. The number of oocytes ovulated with hormones (5.3-49.4 oocytes per head; average, 22.6), rates of in vitro fertilization (12.2-95.3%; average, 70.7%) and subsequent preimplantation development in Whitten's medium (WM) varied greatly among strains. F1 hybrids developed significantly better than other strains of mice and outbred animals did not develop as well as inbred animals. Within inbred mice, coat colour had no significant effect. In addition, the observation of preimplantation development in WM supplemented with ethylenediamine tetraacetic acid (EDTA) showed that the beneficial effect of the chelator was not universal to mouse embryos; EDTA had a good effect on ICR and PW/aSlc embryos but not on AKR or ddY embryos. The results indicate that strain differences should be considered when interpreting reproductive experiments using mouse embryos.

Superiority of the microvascularly augmented flap: analysis of 50 transverse rectus abdominis myocutaneous flaps for breast reconstruction

Our experience with 50 transverse rectus abdominis myocutaneous (TRAM) flap transfers was evaluated as to the types of TRAM flaps, indications for breast reconstruction with a TRAM flap, and complications. The TRAM flap was transferred as a free flap in 7 patients, a unipedicled flap in 14 patients, and a microvascularly augmented flap in 29 patients. Microvascular augmentation was performed through the contralateral inferior epigastric vascular system to the superiorly pedicled muscle in 10 patients who had undergone radical mastectomy and the ipsilateral inferior epigastric vascular system in 19 patients who had undergone modified radical mastectomy. In this series, the incidence of flap-site complications, including total flap loss, partial flap loss, and fat necrosis, was lowest in the microvascularly augmented flap group. Particularly, incidence of partial flap loss in the microvascularly augmented flap group was significantly lower than in the unipedicled flap group (p < 0.01). These outcomes demonstrated the superiority of the microvascularly augmented TRAM flap for breast reconstruction.

Expression of p34cdc2 protein kinase and p53 in supraglottic carcinomas

The clinicopathological significance of the simultaneous expression of the p34cdc2 protein kinase oncogene product and mutant-type p53 oncogene product was studied in 15 supraglottic squamous cell carcinomas. Clinical and histopathological data were recorded from the medical records, and immunohistochemical and DNA cytofluorometric analysis were performed. p34cdc2 was positive in 80% and mutant-type p53 in 53% of the tumors. Their simultaneous expression was seen in 33% of the tumors, but the probability was not statistically significant. Correlations between the expression of p34cdc2 or mutant-type p53 and T, N categories, histological differentiation, and DNA ploidy pattern were not significant. However, when the percentages of p34cdc2 and mutant-type p53-positive cells in the tumor were high, aneuploidy tended to be present and the clinical stage more advanced. It is suggested that the growth and progression of supraglottic carcinomas are associated with the disruption of the regulatory system of the cell cycle.

The cDNA sequence encoding bovine SP-22, a new defence system against reactive oxygen species in mitochondria

We have isolated cDNA clones coding SP-22, an antioxidant protein in mitochondria, from a bovine adrenal medulla cDNA library constructed with (lambda)gt11. The largest clone contained the entire coding sequence for mature SP-22. Since the isolated cDNA clones lacked 5'- and 3'-ends, we determined the sequences of both ends by the "Rapid Amplification of cDNA Ends (RACE)" tecnique. The deduced amino acid sequence of the mature protein region was the same as that determined by protein sequencing. Since SP-22 had a mitochondrial targetting signal, its mitochondrial localization was confirmed.

Inhibitory effects of selenium, vitamin A and butylated hydroxytoluene on growth of human maxillary cancer cells in vitro

The effects of vitamin A, selenium, and butylated hydroxytoluene (BHT) on the growth of a human maxillary cancer cell line were examined in monolayer cell cultures. The colony-forming assay showed a 50% reduction in the survival rate of the cell line at a concentration of 3.6 micrograms/ml of selenium, 28 micrograms/ml of vitamin A, and 74 micrograms/ml of BHT. Flow cytometric analysis with both FITC-labeled bromodeoxyuridine monoclonal antibody and propidium iodide demonstrated an increase of the S-phase fraction in the presence of selenium, an increase of the G0/G1-phase fraction in the presence of vitamin A, and an increase of the G2-M-phase fraction 1 day followed by an increase of G0/G1-phase fraction from the 3rd to 7th day when BHT was added. These results suggest that the mechanisms of inhibition of DNA synthesis by these compounds are different.

Cell growth and pigment production in suspension cultures of a mycobiont isolated from the lichen Cladonia cristaiella

This is the first study on the factors that affect cell growth and the production of secondary metabolites of a lichen mycobiont in liquid culture. An ascospore-derived strain of Cladonia cristatella mycobiont accumulated and excreted red pigments into a liquid medium. Growth of the mycobiont was increased by using liquid Lilly–Barnett medium containing 16% (w/v) sucrose as a carbon source, 0.2% (w/v) L-glutamine as a nitrogen source, and 0.2% (w/v) polypeptone, adjusting pH to 5.0 before autoclaving, and incubating cultures at 20 °C. Pigment production by the mycobiont was increased by using liquid Lilly–Barnett medium containing 4% (w/v) sucrose as a carbon source, 0.2% (w/v) L-asparagine as a nitrogen source, and 0.2% (w/v) malt extract, adjusting pH to 5.0 before autoclaving and incubating cultures at 20 °C. All acetone extracts under any cultural conditions yielded similar HPLC chromatograms. We proved no relationship between cell growth and secondary metabolism based on the nutritional factors in the cultured C. cristatella mycobiont. Key words: lichen, suspension culture, Cladonia cristatella mycobiont, red pigment, production, and growth factor.

Dual effects of trimebutine on electrical responses of gastric smooth muscles in the rat

The effects of trimebutine on the electrical properties of smooth muscle membranes were studied in the isolated rat stomach, the objective being to elucidate the dual actions of this drug on gastric motility. Transmural nerve stimulation elicited a cholinergic excitatory junction potential (e.j.p.) and a nonadrenergic noncholinergic inhibitory junction potential (i.j.p.), and trimebutine inhibited the e.j.p. more than the i.j.p., with no significant change in the acetylcholine-induced depolarization. Trimebutine reduced the interval and, at high concentrations, the amplitude of slow waves. In enzymatically dispersed single cells, the Ca2+ current elicited by depolarization of the membrane was also inhibited by trimebutine. Thus, trimebutine increases slow wave frequency and inhibits cholinergic transmission and Ca2+ influx. The former would enhance while the latter two would depress gastric motility.

Activation of protein kinase C by oxidized diacylglycerols

The effects of 1,2-diacylglycerol hydroperoxide (DAG-OOH), its alcohol (DAG-OH), "unoxidized" 1,2-diacylglycerol (DAG), 1,2-dioleoylglycerol (DOG), and phorbol 12-myristate acetate (PMA) on the activity of protein kinase C (PKC) isolated from rat brain were examined in the presence and absence of phosphatidylserine (PS) and calcium ion. Both DAG-OOH and DAG-OH stimulated the activity of PKC dose- and time-dependently. The ability of additives for PKC activation increased in the order of DOG, DAG << DAG-OOH, DAG-OH < PMA. DAG-OOH and DAG-OH activated PKC even in the absence of PS and calcium ion as PMA does. If DAG-OOH and DAG-OH are released from the oxidized biomembranes by the action of phospholipase C, these components may act like PMA and serve to activate the PKC-dependent signal transduction system.

Lymphoepithelial cyst of the pancreas: a preoperatively diagnosed case based on an aspiration biopsy

This paper reports an extremely rare case of lymphoepithelial cyst of the pancreas. The patient, a 58-year-old man with no subjective symptoms, was found to have a pancreatic tumor during a physical examination. He visited our clinic and was admitted for a follow-up examination. Based on the ultrasonographic findings, superselective angiography, and aspiration biopsy, an epidermoid cyst was diagnosed. Enucleation was easily performed. Macroscopically, this cyst resembled an atheroma. Histologically, the cavity of the cyst was lined with a squamous epithelium with a nucleated layer and below that, lymphatic tissue. No malignancy was found. Tumors of the pancreas with a squamous epithelial covering are extremely rare; only a few such cases have been reported in the literature. As of 1991, only 12 cases, including the present case, had been reported. With the advances in diagnostic techniques, the detection of pancreatic tumors is expected to improve. This paper reports a case in which the use of an aspiration biopsy and superselective angiography proved to be useful in making an accurate diagnosis.

Nucleolar organizer regions in glottic carcinomas: comparison of DNA cytofluorometry and clinicopathological analysis

The significance of nucleolar organizer regions (NORs) and nuclear DNA content in 73 glottic carcinomas was assessed for proliferative activity and tumor progression. NORs stained with silver colloid were counted, and nuclear DNA content was assayed by cytofluorometry. The cytofluorometric study demonstrated that the percentage of tumors with aneuploidy tended to increase as histological differentiation decreased. Survival rates of patients with diploid and aneuploid tumors were not significantly different. AgNOR staining revealed that mean AgNOR numbers rose as histological differentiation of tumors decreased. Moreover, as T and N categories and stages showed advancing malignancy, mean AgNOR numbers tended to rise. However, there was no significant difference in survival rates between tumors with low and with high AgNOR counts. These studies indicate that while AgNOR staining is better than DNA cytofluorometry for determining histological differentiation of glottic carcinoma, neither is of prognostic value at the present time.

Inhibitory effects of selenium, vitamin A and butylated hydroxytoluene on in vitro growth of human tongue cancer cells

The effects of vitamin A, selenium and butylated hydroxytoluene (BHT) on the growth of a human tongue cancer cell line were examined in monolayer cell cultures. A colony-forming assay showed a 50% reduction in the survival rate of the cell line at a concentration of 2.6 micrograms/ml selenium, 60 micrograms/ml vitamin A and/or 38 micrograms/ml BHT. Relatively low concentrations of selenium markedly inhibited glucose consumption. Flow cytometric analysis with both fluorescein-isothiocyanate-labelled bromodeoxyuridine monoclonal antibody and propidium iodide demonstrated an increase in S-phase fractions 1 day after the addition of selenium, increased G0/G1 phase fractions in the presence of vitamin A and increased G2-M phase fractions when BHT was added. These results suggest that these compounds inhibit DNA synthesis of in vitro human tongue cancer cells by different mechanisms.

Morphology of the dorsal lingual papillae in the lesser mouse deer, Tragulus javanicus

The dorsal lingual papillae of the lesser mouse deer were studied morphologically using light and scanning electron microscopy. Four types of papillae, filiform, fungiform, vallate and foliate, were observed. Filiform papillae consisted of larger main papillae with smaller secondary papillae on their anterolateral aspects. Secondary papillae were well distributed over the anterior two-thirds of the tongue, but were very rare or absent in the posterior third. Fungiform papillae were distributed among the filiform papillae, being larger and more abundant on the tip of the tongue. Vallate papillae were round-flat or long-flat, surrounded by a prominent circular groove and a thin annular pad. An important finding was the presence of distinct and prominent foliate papillae on the posterolateral sides of the tongue. Keratinisation of the covering stratified squamous epithelium was relatively weak. Taste buds were observed in the epithelium of the fungiform, vallate and foliate papillae. The lingual papillae of the lesser mouse deer showed some characteristics that differed from those reported for domestic ruminants. These may be related to the feeding habits and the type of food eaten by this species.

[Chronic necrotizing pulmonary aspergillosis in a patient with chronic pulmonary emphysema]

A 67-year-old man with pulmonary emphysema was admitted to the hospital because of left back pain. Chest roentgenography revealed an infiltrate in the left upper lobe, with cavitation, Mycetoma-like shadows were seen in the cavities about 3 weeks later, and a test for the precipitating antibody to Aspergillus fumigatus was positive. Chronic necrotizing pulmonary aspergillosis (CNPA) was diagnosed, and fluconazole was given. A chest roentgenogram taken 4 weeks later showed resolution of both the mycetoma-like shadows and much of the infiltrate. Systemic immunosuppression was highly unlikely: the patient had not been undergoing corticosteroid therapy, and had no predisposing conditions, such as a chronic debilitating illness or diabetes mellitus. In that sense, this case is similar to another reported recently, in which CNPA was associated with chronic obstructive pulmonary disease in an immunocompentent patient.