Chloroplast RNA editing required for functional acetyl-CoA carboxylase in plants.

RNA editing is an important post-transcriptional process in chloroplasts and is thought to be functionally significant. Here we show a requirement of RNA editing for a functional enzyme. In peas, acetyl-CoA carboxylase (ACCase), a key enzyme of fatty acid synthesis, is composed of biotin carboxylase with the biotin carboxyl carrier protein and carboxyltransferase (CT). CT is composed of the nuclear-encoded alpha polypeptide and the chloroplast-encoded beta polypeptide in peas. One nucleotide of the beta polypeptide mRNA, which is edited in pea chloroplasts, converts the serine codon to the leucine codon. We show that this RNA editing is required for functional CT by comparing the unedited and edited recombinant enzymes. In plants not having a leucine codon at the same position, editing was shown to take place so as to create the leucine codon, indicating that editing is needed for in vivo CT activity and therefore for ACCase. To our knowledge, ACCase is an essential enzyme, suggesting that the chloroplast RNA editing is necessary for these plants.

Plume aspects and penetration shape with inclined YAG laser beams.

Nd:YAG laser light beams from three oscillators were separately condensed and then combined at a processing point to enhance the processing ability of the laser system. In this system one or more laser beams must be inclined. An inclined laser beam forms an inclined plume and an inclined penetration under conditions of high laser peak power and high energy input (region I). From the direction and size of the plume, the penetration of a weld bead can be evaluated. In the case of two or three laser beam combinations, keyholes exist for each laser beam separately in region I.

[A study of calcium metabolism in calcium-containing stone formers].

To clarify the pathogenesis of calcium-containing urinary stone, calcium metabolism of the 113 patients with calcium-containing stone was studied by fasting and oral calcium loading test. The stone patients were classified into four groups. Those were normocalciuria (NC, n = 60), absorptive hypercalciuria-1 (AH-1, n = 26), absorptive hypercalciuria-2 (AH-2, n = 16) and renal hypercalciuria (RH, n = 11). In the AH-1 group, hypercalciuria resulted from enhancement of intestinal calcium (Ca) absorption. The increase in serum Ca from absorbed Ca increased renal filtered load of Ca. Urinary excretion of Ca was correlated to that of sodium (Na) in fasting and Ca load, and both increments were also correlated in Ca load. As of this fact, the increase in Na excretion was responsible for a cause of hypercalciuria in the AH-1 group. In the RH group, the serum ionized Ca level and % tubular reabsorption of Ca were significantly lower than those of other groups. Urinary excretion of Ca and Na ratio was significantly higher than that of the NC and AH-1 groups. This condition was due to an impaired renal tubular reabsorption of Ca and the resulting secondary hyperparathyroidism. These findings suggested was response disorder of distal tubular to parathyroid hormone. Urinary excretion of phosphorus (P) was correlated to that of Na in fasting and Ca load, and both increments were also correlated in Ca load in the AH-1 group. The increase in urinary excretion of P resulted from the secondary hyperparathyroidism in the RH group.(ABSTRACT TRUNCATED AT 250 WORDS)

Increase in the amount of elongation factor 2 in rat liver by peroxisome proliferators.

The changes in protein phosphorylation during induction and deinduction of peroxisome proliferation in rat liver by three types of proliferators were studied by in vitro phosphorylation assay. Among the variously phosphorylated proteins, an increase during induction and a decrease during deinduction in phosphorylation of P100, a cytosolic protein having a molecular weight of 100 kDa, was most remarkable. The time course of enhancement of phosphorylation by the administration of the proliferators, however, was not parallel with proliferation of peroxisome but with increase in the liver DNA content. Amino acid sequencing of the protein indicated the identity of its N-terminal 17 amino acid residues with those of elongation factor 2 (EF2). Increase in the amount of EF2 by peroxisome proliferators was confirmed by immunoblotting and this was almost parallel with peroxisome proliferation, suggesting that both increase in the amount of EF2 and some changes in phosphorylation activities account for a large increase in in vitro phosphorylation of EF2 by the administration of peroxisome proliferators.

Application of the environmental SEM in human dentin bleached with hydrogen peroxide in vitro.

The environmental SEM (E-SEM) can be used unfixed biological samples under a low vacuum and wet condition. In this study, the fractured dentin of unfixed human teeth was treated with a 30% hydrogen peroxide solution (H2O2) for the examination of tooth-bleaching prior to the E-SEM and a conventional SEM. The peritubular matrix (PM) always showed a few cracks along the long axis of a dentinal tubule, and the ends of fine fibrils rose to the smoothly changed surface of the intertubular matrix (IM). The E-SEM with non-fixation and the conventional SEM following fixation indicated that the hydrogen peroxide solution easily permeated the PM and dissolved the non-fibrillar substance including the cracks of the PM by the constriction. In the IM, the solution may partially dissolve the organic parts within mineralized fibrils as well as non-fibrillar substance between the fibrils, although these remnants might precipitate again there.

[Antiandrogen therapy of benign prostatic hypertrophy: clinical effects of allylestrenol evaluated by transrectal ultrasonographic measurement].

A multicenter trial was carried out on 100 patients with benign prostatic hypertrophy to elucidate the efficacy of anti-androgen therapy with allylestrenol (AE). AE was administered at a daily dose of 50 mg for 16 weeks to the patients and its efficacy was evaluated with subjective symptom scores, residual urine volume and uroflow rates. The effects of AE on prostatic volume and morphology were evaluated using transrectal ultrasound. Of these patients 65 completed the protocol, and only three patients withdrew from the study owing to side effects. Very modest adverse effects on sexual performance were seen in one patient. In this study, significant beneficial effects of AE on symptom scores, residual urine, maximum flow rate, and prostate size were demonstrated. However, volumetric reduction was not associated with urodynamic improvement. Prostatic shape was not changed throughout the study. These findings suggest that allylestrenol can be used as an alternative to prostatectomy in patients who are at high risk for surgery.

[Clinical study of UFT chemotherapy in renal cancer. Kyushu University Cooperative Study Group of Renal Cancer].

Clinical effects of UFT chemotherapy for renal cancer were evaluated by 19 collaborating hospitals. UFT (300-600 mg/day) was administered for more than 3 months. Of the 30 patients entered in this study, 21 were evaluable for the antitumor effects of the drug. Of the 21 evaluable patients, complete response (CR) was obtained in 2 patients, partial response (PR) in 1, no change (NC) in 7, progressive disease (PD) in 11, respectively. The response rate was 0% in patients with primary lesion and 21.4% in nephrectomized patients with metastatic lesion. Responses were observed in the metastases of lung, pleura and mediastinal lymph node. The main side effects in 27 patients were gastrointestinal symptoms. No significant abnormality was noted on blood laboratory data. In one patient the drug was discontinued within 3 months because of gastrointestinal symptoms. These results suggested that UFT chemotherapy for advanced renal cancer was clinically effective.

[Correlation of proliferation index with submucosal invasion of hypopharyngeal cancer].

Proliferation index of biopsied specimens from 11 cases of hypopharyngeal carcinoma was studied immunohistochemically using anti-BrDU monoclonal antibody. S-phase cell labelling index (SLI) was measured and compared with the extent of submucosal invasion that was evaluated histologically in each extirpated specimen by means of continuous large section technique. Conclusions were as follows: 1. The largest SLI was obtained in a moderately differentiated carcinoma, and calculated up to 56, while the smallest was encountered in a well differentiated carcinoma as 18. Mean value in these 11 cases was 35. 2. It seemed likely that moderately or poorly differentiated carcinomas show larger SLI, but its statistical significance could not be delineated in these materials. 3. Submucosal invasion was much longer in the oral direction than in the anal. The longest invasion was observed in a case that showed the largest SLI, and measured up to 22 mm. The shortest invasion, on the contrary, was seen in a case with the smallest SLI, and was only 9 mm. Mean value in these 11 cases was 14.4 mm. 4. SLI correlates well in every case to the extent of submucosal invasion toward the oropharynx. 5. SLI evaluated preoperatively in biopsied specimen may help to indicate an ample safety margin at the surgery.