Reinjection experiment at the matsukawa vapor-dominated geothermal field: Increase in steam production and secondary heat recovery from the reservoir

A reinjection experiment has been conducted in an attempt to sustain reservoir pressure and steam production and to extract remaining heat energy in the superheated reservoir in the Matsukawa vapor-dominated geothermal field. This experiment was undertaken because the increase in superheat of produced steam and the decline of steam production are the current major issues for stable operation of the power plant. Almost all the reinjected fluid into well MR 1 was recovered from well M5, and the steam production of well M5 has increased by approximately 67%.     

Analysis of multiple indicator dilution curves for estimation of renal tubular transport parameters

A model is developed to estimate the renal tubular secretory parameters by the multiple indicator dilution (MID) technique. The model allows the calculation of influx (from plasma space to tubular cell), efflux (from tubular cell to plasma space) and sequestration (from tubular cell to luminal side) rate constants. A program using the MID-statistical analysis with least squares fitting (SALS) system for the estimation of these parameters is presented. A trapezoid rule and a non-linear least squares regression were used to carry out definite integrals of cubic spline function and least squares fitting, respectively. The system presented seems to be useful for the precise and rapid estimation of the tubular secretory rate constants.     

Structure and expression of the tobacco nuclear gene encoding RNA-binding protein RZ-1: the existence of an intron in the 3''-untranslated region

We investigated prolactin (PRL) and growth hormone (GH) secretion during acute and late abstinence following methylphenidate (MP) administration. Ten male patients who were undergoing acute cocaine abstinence and nine control subjects were randomly assigned into one of two possible sequences of MP and placebo, with each experimental condition occurring on two successive days. This procedure was repeated after 7 days for the patients. Baseline measures were analyzed by analysis of variance (ANOVA) with post hoc tests. Measures of MP challenge were analyzed by analysis of covariance (ANCOVA) with baseline as the covariate. Acute abstinence was compared with control values and then to late abstinence. Plasma levels of PRL, GH, and MP were measured along with a measure of clinical symptoms. Patients had higher basal PRL concentrations during acute abstinence compared with controls, and patients showed no difference when compared to themselves after 7 days (late abstinence). Provocation with MP yielded exaggerated PRL and GH responses in patients during acute abstinence compared with control values, and ANCOVA also revealed a significant increase in PRL response during late abstinence compared with acute abstinence. GH was a less sensitive indicator than PRL. Craving was exacerbated by MP during both acute and late abstinence and was possibly increased at late abstinence. This indicates that the perturbation in dopamine regulation persists and may be increased as clinical recovery occurs for most subjective symptoms. Blood pressure changes were variable and interpretation was uncertain.     

Pharmacokinetics of pentazocine and its occupancy of opioid receptors in rat brain

In order to assess quantitatively the pharmacodynamic process of pentazocine (PTZ), time courses of its plasma concentration and of the occupation of specific opioid receptors in the brain were investigated after intravenous (i.v.) administration of PTZ to rats. The plasma concentration of PTZ was determined by HPLC and the pharmacokinetic parameters were analyzed using nonlinear least-squares analysis. Measurement of ex vivo receptor occupation was made by comparing the specific [3H]naloxone (opioid receptor antagonist) binding in vitro to the crude P2-synaptosomal fractions between vehicle-treated rats (control) and PTZ-treated rats. Following the i.v. administration of PTZ, the occupancy of specific opioid receptors decreased rapidly until 10 min, depending on the two pharmacological doses (2.5 and 10 mg/kg). The results strongly suggest the fast binding kinetics of PTZ in terms of its association with and dissociation from specific opioid receptor sites in the brain in addition to its fast rate of disappearance from the brain compartment. Furthermore, we demonstrated that the time profile of receptor occupancy correlated well (r = 0.8650) with that of the unbound concentration in plasma until 120 min after the i.v. administration of PTZ to rats.     

Comparative hepatic transport of desglycylated and cyclic metabolites of rilmazafone in rats: analysis by multiple indicator dilution method

Rilmazafone (RZ) is an orally active sleep inducer which can be activated to its cyclic form (M1) via the labile desglycylated metabolite (DG). In this scheme, RZ is exclusively metabolized to DG and M1 by aminopeptidases in the small intestine. The concentration of M1 in the systemic plasma after oral administration of RZ has been reported to be higher than that observed after administration of M1, due to the lower hepatic extraction of DG than M1 (Koike et al., Drug Metab. Dispos., 16, 609 (1988)). In the present study, the disposition of DG and M1 in rat liver was investigated, using the multiple indicator dilution method. The hepatic availabilities (F) of DG and M1, assessed from the recovery into the hepatic vein, were 0.16 and 0.07, respectively, which was consistent with the previous in vivo finding that the first-pass elimination of M1 was greater than that of DG. The kinetic analysis based on the distributed model showed that the influx (k'1) and efflux (k'2) rate constants for M1 were larger than those for DG, whereas no significant difference in the sequestration rate constant (k'3) was observed between the two ligands. Based on the concept proposed by Miyauchi et al. (J. Pharmacokinet. Biopharm., 15, 25 (1987)), it was suggested that the determinant factor of the hepatic intrinsic clearance was the influx clearance for both ligands, because the values of k'2 for each ligand were much smaller than the respective k'3 values. It was concluded that the higher plasma concentration of M1 after oral administration of RZ than that observed after administration of M1 is due to the fact that the hepatic uptake of DG is lower than that of M1.     

Pneumocystis carinii pneumonia in mutant mice deficient in both TCRalphabeta and TCRgammadelta cells: cytokine and antibody responses

PURPOSE: A phenomenon known as hidden penis has numerous origins, including congenital buried penis and obesity with descent of the escutcheon. No previous report to our knowledge mentions abnormal hypermobility of ventral skin and dartos fascia, which is a major cause of surgical treatment failures. Because the skin and dartos fascia are inadequately attached to Buck's fascia, the corporeal bodies telescope proximally inside the scrotum and pubis. Therefore, the subdermis of the penoscrotal junction must also be tacked to the tunica albuginea ventrally to stabilize the proximal penile skin and prevent the penis from retracting into the scrotum. The surgical technique for correction of the hidden penis in adult and pediatric patients with adequate penile shaft skin is described. MATERIALS AND METHODS: Surgery for hidden penis from multiple causes was performed in 6 adults and 7 children. Tacking sutures were taken from the subdermis of the ventral penoscrotal junction to the tunica albuginea in all cases. A combination procedure with either suprapubic dermatolipectomy, tacking of the penopubic subdermis to the rectus fascia, penoscrotal Z plasty, circumcision revision or lateral penile shaft Z plasty also was performed in some patients. RESULTS: Improvement was noted in all cases. One child requires suprapubic lipectomy for optimal improvement and 3 minor wound problems occurred. CONCLUSIONS: Surgery for hidden penis achieves marked aesthetic and often functional improvement. Surgical failure can be diminished by placing ventral tacking sutures from the tunica albuginea to the subdermis of the penoscrotal junction.     

Triple bioaffinity mass spectrometry concept for thyroid transporter ligands

For the analysis of thyroid transporter ligands, a triple bioaffinity mass spectrometry (BioMS) concept was developed, with the aim at three different analytical objectives: rapid screening of any ligand, confirmation of known ligands in accordance with legislative requirements, and identification of emerging yet unknown ligands. These three purposes share the same biorecognition element, recombinant thyroid transport protein transthyretin (rTTR), and dedicated modes of liquid chromatography-mass spectrometry (LC-MS). For screening, a rapid and radiolabel-free competitive inhibition MS binding assay was developed with fast ultrahigh performance-liquid chromatography-electrospray ionization-triple-quadrupole-MS (UPLC-QqQ-MS) as the readout system. It uses the nonradioactive stable isotopic thyroid hormone (13)C(6)-l-thyroxine as the label of which the binding to rTTR is inhibited by any ligand such as thyroid drugs and thyroid endocrine disrupting chemicals (EDCs). To this end, rTTR is either used in solution or immobilized on paramagnetic microbeads. The concentration-dependent inhibition of the label by the natural thyroid hormone l-thyroxine (T4), as a model analyte, is demonstrated in water at part-per-trillion and in urine at part-per-billion level. For confirmation of identity of known ligands, rTTR was used for bioaffinity purification for confirmation of naturally present free T4 in urine. As a demonstrator for identification of unknown ligands, the same rTTR was used again but in combination with nano-UPLC-quadrupole time-of-flight-MS (nLC-Q-TOF-MS) and urine samples spiked with the model "unknown" EDCs triclosan and tetrabromobisphenol-A. This study highlights the potential of BioMS using one affinity system, both for rapid screening and for confirmation and identification of known and unknown emerging thyroid EDCs.     

Improved method for visualizing coated pits,microfilaments, and microtubules in cryofixed and freeze-substituted plant cells

We have optimized the conditions for visualizing microfilaments, microtubules, and coated pits in the cortical cytoplasm of high-pressure frozen and freeze-substituted plant cells, in both tobacco root tips and onion cotyledons, individual microfilaments and the supramolecular structure of coated pits can be seen clearly in freeze-substituted samples treated with OsO4 at 40 degrees C followed by 5% uranyl acetate. Treatment with uranyl acetate alone resulted in poorly stained cytoplasmic organelles, whereas microfilaments were difficult to discern in specimen treated with OsO4 alone. The combination of a 40 degrees C OsO4 staining step followed by staining with uranyl acetate at 4 degrees C should prove useful for more detailed plant cytoskeletal/membrane studies in the future.     

Large-scale production of saikosaponins through root culturing of Bupleurum falcatum L. using modified airlift reactors

Modification of internal configuration of a bubble column, airlift and stirred tank reactor (10-200 L) was made for root cultures of Bupleurum falcatum L. Agitation with an impeller covered with partition mesh was ineffective for a 10-L modified reactor, because it caused intensive foaming and subsequent overflow of the culture medium even at a low rotation speed of 50 rpm and a low aeration rate of 0.1 vvm (volume per volume of medium). In contrast, efficient aeration through a ceramic sparger placed at the bottom of a 20-L bubble column reactor yielded approximately 25 g/L of dry roots and 500 mg/L of saikosaponin-a and saikosaponin-d over 42 days. On a 200-L scale, however, the roots became flocculated under the upper perforated plate initially positioned near the middle of the reactor, forming a firm disk of roots and a large empty space between the disk and the medium. Thus, the roots had poor contact with the medium, which severely suppressed their growth. To avoid this flocculation, a bottom perforated plate and draft tube were installed as a partitioning device separating the culturing area (outside the draft tube) from the aeration area (inside the draft tube). The draft tube was made of a stainless steel mesh rather than a solid material, and the tube greatly increased the root yield in the 20-L reactor. This configuration was successfully applied at the 200-L scale, yielding 500-600 mg/L of saikosaponin-a and saikosaponin-d over 56 days.     

Remarkable Improvement in Efficiency of Filtration Method for Fullerene Purification

Filtration of fullerene extract through thin layer of powdered activated carbon fiber was reported as a very practical process for fullerene purification. In order to make it more efficient, the conditions of the filtration were further investigated. As a result, 1,2,4-trimethylbenzene with high fullerene solubility was found to be employed as solvent to give pure C₆₀ and C₇₀ in moderarte to excellent yields, reducing a volume of solvent, an amount of activated carbon and a time for purification. The efficiency of the improved filtration method presented here is considered to be comparable to or even better than that of the previous methods.