Physicochemical properties of amorphous clarithromycin obtained by grinding and spray drying

In order to characterize the amorphous clarithromycin (CAM) obtained by grinding and spray drying, physicochemical properties (crystallinity, thermal behavior, stability and solubility parameters) were evaluated. From powder X-ray diffraction, it was estimated that the crystalline state of CAM was changed into an amorphous state by grinding and spray drying. In differential scanning calorimetry measurements, both broad and sharp peaks for crystallization were observed in ground samples, whereas spray dried samples showed one broad peak due to crystallization. As to the stability test under high humidity, structural difference was confirmed between ground CAMs and spray dried CAM. The heat of dissolution of ground CAMs was greater than that of intact CAM. In the solubility parameter measurement, the increase of the special term, deltas, indicated that the energy change was due to the polarity of the surface energy of the powder particles by grinding.

[Hyperkalemia after irradiated blood transfusion]

A 70-yr-old woman was scheduled for hepatectomy and colectomy. We gave general anesthesia with N2O-O2-Isoflurane and continuous epidural block. About 4.5 hours after the start of the operation, 8 units of irradiated RBC-MAP were transfused. Then elevated T waves were noted and serum potassium was increased to 5.4 mmol.l-1. The transfusion of RBC-MAP was stopped and calcium gluconate was administered immediately. Then serum potassium decreased to 4.3 mmol.l-1 and ECG returned to normal. During the operation, 10 units of irradiated RBC-MAP were transfused and 8 units of them had been stored more than 1 week after the irradiation. We suspect that hyperkalemia was induced by high concentration of potassium in RBC-MAP. Irradiation of blood products is an effective way to prevent post-transfusion graft versus host disease. However, the increase in potassium is greater in the irradiated than nonirradiated RBC-MAP. We must pay attention to the high concentration of potassium in th eplasma of RBC-MAP stored after irradiation.

Urinary excretion of the vitronectin receptor (integrin alpha V beta 3) in patients with Fabry disease

A renal disorder is one of the important manifestations of Fabry disease, but the details of the pathogenesis have not been clarified yet. We examined the possibility that the vitronectin receptor (VNR, integrin alpha V beta 3), one of the integrins, is involved in the progression of the renal injury in Fabry disease. We measured the urinary excretion of beta 3 originating from VNR in Fabry patients by immunoblotting analysis and enzyme-linked immunosorbent assay (ELISA). Immunofluorescent microscopic analyses for VNR and globotriaosylceramide were performed on urinary sediments from Fabry patients. Furthermore, beta 3 and vitronectin in kidney tissues were analyzed immunohistochemically. Immunoblotting analysis and ELISA showed that the urinary excretion of beta 3 originating from VNR was significantly increased in the Fabry group compared with both the pathological and healthy control groups. Immunofluorescent microscopy revealed the expression of VNR and accumulation of globotriaosylceramide in urinary sediments from the Fabry patients. Increased expression of beta 3 was observed in glomerular epithelial cells, and in Bowman's capsular epithelial layer and tubular cells, and the amount of vitronectin was moderately increased in the kidney tissues from the Fabry patients. The urinary excretion of VNR was increased, and the expression of VNR was observed in Fabry kidney tissues. The expression of VNR may be involved in the progression of the renal injury in this disease.

Right ventricular responses to vagus stimulation of fibers to discrete cardiac regions in dog hearts

To investigate the role on the right ventricular function of the parasympathetic nerves in discrete cardiac regions, we studied the effects of stimulation of the intracardiac parasympathetic nerves to the atrioventricular (AV) nodal area (AVPS) or sinoatrial (SA) nodal area (SAPS), and stimulation of the cervical vagus nerves (CVS) on the right atrial and ventricular function in the autonomically decentralized heart of the anesthetized dog. AVPS prolonged AV conduction time (AVCT) and decreased the ventricular rate without changes in atrial rate, right atrial 'a' wave pressure (RAP), its first derivative (RAd P/dt), right ventricular pressure (RVP) and its first derivative (RVd P/dt) in the spontaneously beating heart. On the other hand, AVPS prolonged the AVCT in the atrium paced electrically and further decreased the ventricular rate with decreases in ventricular pressure responses but not atrial responses. SAPS decreased atrial and ventricular rates without AVCT changes and attenuated the right atrial and ventricular pressure responses. In the atrial paced heart, SAPS decreased the ventricular responses less than those responses in the spontaneously beating heart with similar decreases in the atrial pressure responses, but it changed neither the AVCT nor ventricular rate. On the other hand, CVS decreased the atrial and ventricular rate or pressure responses, and increased the AVCT. CVS in the paced heart also decreased the atrial and ventricular pressure responses with the prolongation of AVCT. The cardiac responses to parasympathetic stimulations were abolished by atropine. These results suggest that AVPS decreases ventricular rate without direct right ventricular pressure effects but the negative chronotropic effects of AVPS and SAPS decrease the ventricular pressure responses rate-dependently in the dog heart.

Effects of low temperature on the chronotropic and inotropic responses to zatebradine, E-4031 and verapamil in isolated perfused dog atria

We investigated the effects of hypothermia (25 degrees C) on the chronotropic and inotropic effects of zatebradine (a blocker of hyperpolarization-activated inward current, I(f)), E-4031 (a blocker of the rapid type of the delayed rectifier K+ current, I(Kr)) and verapamil, and on the positive cardiac responses to isoproterenol after treatment with zatebradine and E-4031 in isolated, blood-perfused dog atria. Hypothermia shifted the dose-response curves to the right for the negative chronotropic and inotropic effects of verapamil and for the negative chronotropic and positive inotropic effects of zatebradine, but not for the negative chronotropic and positive inotropic effects of E-4031. Hypothermia attenuated the positive chronotropic response to isoproterenol or Bay k 8644 (an L type Ca2+ channel agonist) and was attenuated more than the inotropic one. Zatebradine selectively inhibited the positive chronotropic response to isoproterenol at a normal temperature, but in hypothermia, it inhibited neither the chronotropic nor inotropic responses. E-4031 did not affect the positive responses to isoproterenol. These results suggest that verapamil and zatebradine but not E-4031 influence the atrial rate and contractile force much less in hypothermia than in normothermia and that the I(f) and inward Ca2+ current are sensitive to hypothermia in the heart.

Isolation and characterization of the yeast las21 mutants, which are sensitive to a local anestheticum, tetracaine

We isolated and characterized yeast mutants whose growth is sensitive to a local anestheticum tetracaine and, at the same time, temperature sensitive. These mutants were collectively called las mutants (local anestheticum sensitive). The las21 mutants were analyzed in this study. The wild type LAS21 gene was cloned by exploiting temperature sensitivity of the las21 mutants and we found that LAS21 encodes ORF YJL062w which has not been analyzed before. Las21p is putative membrane protein belonging to the major facilitator super family containing plural membrane spanning domains. Complete elimination of the LAS21 ORF did not kill the cells but made their growth temperature sensitive. Interestingly, the complete loss of the LAS21 gene canceled the sensitivity to tetracaine. The ability of the las21 mutants to grow at a higher temperature was recovered in the various media containing an osmotic stabilizer or salts. Furthermore, temperature sensitivity of the las21 mutants was partially suppressed by introduction of PKC1, encoding protein kinase C, on a high copy vector. We found some genetic interactions between LAS21 and Ras/cAMP cascade genes. These results suggest that LAS21 defines unknown pathway regulating the stress response of yeast.

Characterization of amorphous ursodeoxycholic acid prepared by spray-drying

The objectives of this study were to characterize the amorphous state of ursodeoxycholic acid (UDCA) samples prepared by spray-drying, and to demonstrate the applicability of thermal and water-vapour-adsorption techniques for studying the material. Amorphous UDCA was prepared by spray-drying a solution of the compound in a mixture of ethanol and dichloromethane. The amorphous material was characterized by powder X-ray diffraction, infrared (IR) spectroscopy, isothermal microcalorimetry, differential scanning calorimetry (DSC) and water-vapour adsorption. When the inlet-air temperature of the spray drier was increased beyond 140 degrees C, the intensity of X-ray diffraction peaks from crystalline UDCA decreased and the IR bands in the hydroxyl-stretching and carboxyl-stretching regions changed. Dissolution of intact and spray-dried samples of UDCA prepared at 60 and 100 degrees C was an endothermic process but the dissolution became exothermic with increasing inlet-air temperature. UDCA samples differing in crystallinity were obtained, depending on the inlet-air temperature. A good correlation was obtained between the heat of solution and the heat of crystallization determined from DSC peak area. A good correlation was also obtained between the heat of solution and the crystallinity determined by Ruland's method from X-ray diffraction patterns. The amount of water vapour adsorbed on UDCA samples increased with increasing inlet-air temperature, indicating hydrogen bonding between water molecules and the hydroxyl groups or the carboxyl groups of amorphous UDCA. These results indicate that measurement of adsorption of water vapour and thermal analysis can both be used to evaluate the crystallinity of solid substances.

Fluorometric Studies of Pyrene Adsorption on Porous Crystalline Cellulose

Pyrene crystals were physically mixed with either porous crystalline cellulose (PCC) or octa decyl siryl silica-80Tm (ODS). Solid-state fluorescence spectra of pyrene were analyzed to estimate the interaction between pyrene and porous materials. Pyrene monomer emission was observed at 398 nm immediately after being mixed with PCC, while pyrene crystals showed only excimer emission at 475 nm, indicating that the pyrene molecules adsorbed onto the PCC surface in a short period. For the PCC system containing 1.0% pyrene, long-term storage caused an increase in the intensity of excimer-like emission peak at 477 nm accompanied by a decrease in the intensity of monomer emission peak at 398 nm. For the ODS system containing 1.0% pyrene, spectrometric changes were similar to those for the PCC system. In the process of interaction formation between pyrene and an additive, a two-step mechanism was proposed, i.e., the adsorption of pyrene molecules onto the surface of porous additives, and the formation of a ground state dimer of pyrene. The formation of dimeric pyrene could be associated with the surface polarity of additives. Copyright 1998 Academic Press.

X-ray linear birefringence and linear dichroism in a cobalt crystal measured with a tunable X-ray polarimeter

X-ray linear birefringence and linear dichroism spectra have been measured simultaneously and quantitatively for the first time. The sample was a hexagonal cobalt single-crystal foil. The apparatus used was an energy-tunable X-ray polarimeter, consisting of a polarizer, a phase retarder and an analyser. The X-ray energy was scanned over a range of 350 eV near the K-absorption edge. The Kramers-Kronig relation between the refraction and absorption anisotropy has been confirmed on an absolute scale. The phase-difference sensitivity of the polarimeter as a polarization inferometer is as small as 2pi/10000, which is about 100 times smaller than that of the Bonse-Hart inferometer.

X-ray triple refraction and triple absorption in a cobalt-complex crystal

X-ray triple refraction and triple absorption have been quantitatively measured for the first time. The samples were (100)-, (010)- and (001)-oriented plates of a cobalt-complex monoclinic crystal. The apparatus used was an energy-tunable X-ray polarimeter with a phase retarder. The X-ray energy was scanned over a range of 150 eV near the cobalt K-absorption edge. Both the spectra of ellipticity and rotation of polarization were completely different for each crystal plate, which revealed that the biaxial crystal had three refractive indices and three absorption coefficients in the X-ray region. The Kramers-Kronig relation between the real and imaginary parts of the dielectric anisotropy has been quantitatively confirmed for all three different orientations.

Comparative effects of Ringer's acetate and lactate solutions on intraoperative central and peripheral temperatures

STUDY OBJECTIVES

To compare the effects of Ringer's lactate (LR) and Ringer's acetate (AR) solutions on core body and peripheral temperatures during isoflurane or sevoflurane anesthesia.

DESIGN

Prospective, randomized study.

SETTING

Operating rooms of a university hospital.

PATIENTS

60 ASA physical status I and II patients undergoing general surgery.

INTERVENTIONS

Following induction with 5 mg/kg of thiamylal and 0.1 mg/kg of vecuronium, patients were randomly assigned to one of four groups (15 patients per group). They received inhalation anesthetics (66% nitrous oxide [N2O] and 1.0% to 2.0% isoflurane or 1.3% to 2.6% sevoflurane) and LR or AR.

MEASUREMENTS AND MAIN RESULTS

Tympanic membrane (central) temperatures, forearm temperatures, and fingertip temperatures were recorded during surgery every 30 minutes. Tympanic membrane temperatures in the patients given AR were significantly higher than those given LR during isoflurane anesthesia 5 and 30 minutes after induction of anesthesia. However, this was not the case for sevoflurane anesthesia. There were no significant differences in forearm and fingertip temperatures or fingertip bloodflow among the four groups.

CONCLUSION

There was no significant difference between AR and LR in the preservation of heat during either sevoflurane or isoflurane anesthesia. However, AR may be superior to LR for maintaining central temperature during the early period of isoflurane anesthesia.

The minimum alveolar concentration of sevoflurane in rats

There are only limited data on sevoflurane minimum alveolar concentration (MAC) in rats. This study was designed to determine the minimum alveolar concentration value for sevoflurane in younger and older rats. Minimum alveolar concentration determination was performed in spontaneously breathing animals, 9-week-old rats (younger, n = 8) and more than 13-month-old rats (older, n = 8). Rats were instrumented with a silastic catheter in the abdominal aorta via the femoral artery to allow for arterial blood gas sampling. Subsequently, minimum alveolar concentration for sevoflurane was determined in 40 younger and 38 older rats. Minimum alveolar concentration for sevoflurane in younger rats was significantly higher than in the older rats (2.68 +/- 0.19 vs. 2.29 +/- 0.19, P < 0.001). Subgroup analysis indicated that minimum alveolar concentration for sevoflurane was not affected by the presence of an arterial catheter in the abdominal aorta (younger, 2.75 +/- 0.08 vs. 2.67 +/- 0.21; older, 2.23 +/- 0.19 vs. 2.30 +/- 0.18). Minimum alveolar concentration is profoundly affected by the age of the animal, but not by limited instrumentation.

Evaluation of amorphous ursodeoxycholic acid by thermal methods

PURPOSE

The purpose of this study was to characterize the amorphous state of ursodeoxycholic acid (UDCA) samples by using isothermal microcalorimetry, X-ray diffraction, infrared (IR) spectroscopy and solid state carbon 13 nuclear magnetic resonance (13C-NMR) spectroscopy, and to demonstrate the application of the thermal methods (microcalorimetry and differential scanning calorimetry (DSC) for studying the amorphous state and clarifying the dissolution mechanism of UDCA.

METHODS

Amorphous UDCA was prepared by grinding and rapid cooling of the melts. The heat of solution of UDCA was measured by an isothermal heat-conduction twin microcalorimeter at 25.0 degrees C. Some physicochemical properties of amorphous UDCA were also studied.

RESULTS

The intensities of X-ray diffraction peaks of crystalline UDCA decreased with an increase in grinding time. The heat levels of solution of crystalline UDCA and UDCA ground for 1 min were endothermic, and became exothermic with an increase in grinding time. A good correlation was obtained between the heat of solution and the heat of crystallization determined from the peak area in DSC. Although no significant difference was observed in X-ray diffraction patterns of amorphous UDCA prepared by the two methods, significant differences were recognized in DSC, IR and 13C-NMR, and the heat of solution indicated different values among the two samples. The stability of amorphous UDCA samples stored under 74.5% relative humidity at 40 degrees C was found to depend upon the preparation methods.

CONCLUSIONS

Different states of amorphous UDCA were obtained depending on the preparation method. The application of thermal methods to evaluate the amorphous state was demonstrated. The mechanism of dissolution of UDCA was discussed from the results of the heat of solution examination.

Detection and quantitation of HBV DNA by semi-nested PCR in donated blood: comparison with HBV serological markers

To detect and quantitate hepatitis B virus (HBV) DNA, semi-nested polymerase chain reaction (PCR) method was designed for amplifying the HBV core region DNA. Cloned HBV core region DNA was used as a quantitation control, and upon electrophoresis of the semi-nested PCR product, one, two, or three bands of amplified DNA were observed using a small (< 50 mol), moderate (around 200 mol), or large (> or = 1250 mol) quantity of the template DNA, respectively. Using this semi-nested PCR method, HBV DNA was quantitated in donated blood and tested for HBV serological markers. Most of the HBV surface antigen (HBsAg) high titer samples showed three bands on the electrophoresis, indicating a high level of HBV DNA, while most of the HBsAg low titer samples showed one band, indicating a low level of HBV DNA. HBV DNA was detected in 7 out of 36 HBsAg-undetectable and anti-HBc-positive samples (19.4%) but all 7 showed one band, indicating a low level of HBV DNA. In almost all of the HBV e antigen-positive samples the HBsAg titer was high, and three bands were observed indicating a high level of HBV DNA.

Effects of grinding and humidification on the transformation of conglomerate to racemic compound in optically active drugs

The effects of grinding and humidification on the transformation of conglomerate to racemic compound have been investigated by X-ray powder diffraction (XPD), differential scanning calorimetry (DSC) and infrared (IR) spectroscopy for leucine, norleucine, valine, serine, tartaric acid and malic acid. Racemic physical mixtures were prepared by physical mixing of equimolar quantities of D and I. crystals using a mortar and pestle. Ground mixtures were obtained by grinding the physical mixtures with a vibrational mill. Humidification was performed by storing the physical mixtures and the ground mixtures in a desiccator containing saturated aqueous salt solutions at 40 degrees C. When physical mixtures of malic acid, tartaric acid and serine were ground, the XPD peaks of the racemic compounds were observed. The XPD patterns of humidified physical mixtures of these compounds also showed the formation of the racemic compounds. This indicated that grinding or humidification of malic acid, tartaric acid and serine induced the transformation of conglomerate to racemic compound crystals. When, on the other hand, the physical mixtures of valine, leucine and norleucine were ground, peaks of racemic compounds were not detected in the XPD pattern. After humidification of the ground mixtures of valine, leucine and norleucine, however, the XPD peaks of racemic compounds were observed. DSC and IR studies revealed consistent results. We concluded that grinding or humidification of malic acid, tartaric acid and serine could induce the transformation of a conglomerate to racemic compound. In contrast, humidifying after grinding was needed to bring about the transformation in leucine, norleucine and valine.

Use of an alkaline phosphatase-conjugated oligonucleotide probe for the gene encoding the bundle-forming pilus of enteropathogenic Escherichia coli

An alkaline phosphatase-conjugated 29-base oligonucleotide probe was developed to detect the gene encoding the bundle-forming pilus of enteropathogenic Escherichia coli. The sensitivity and specificity of the probe versus the results of localized adherence in the HEp-2 cell assay and fluorescent actin staining assay positivity were 95.7 and 100%, respectively.

Immunological analysis of organized pneumonia with eosinophilic pleural effusion

A 73-year-old man developed organized pneumonia with severe right-sided eosinophilic pleural effusion (PE). CD69+ and HLA-DR+ eosinophils in PE were 90 and 31%, respectively, but were undetectable in peripheral blood (PB). CD4+, CD45RA+ (naive) and CD4+, CD45RO+ (memory) cells in PB, PE and bronchoalveolar lavage (BAL) were 10.9, 8.4, 2.5 and 22.7, 38.3 and 16.4%, respectively. CD8+, CD45RA+ (naive) and CD8+, CD45RO+ (memory) cells in PB, PE and BAL were 3.5, 4.7, 1.0, and 8.9, 11.3 and 46.0%, respectively. The concentrations of interleukin-5 (IL-5) and IL-6 in PE were 1,680 and 2,797 pg/ml, respectively; however, these cytokines were undetectable in PB. The patient died 1 month after surgery to remove right thickened pleura. Microscopic findings showed right fibrinous pleuritis and organized pneumonia.

Association between the extent of sclerotic changes in iliac arteries and long-term prognosis in patients with ischemic heart disease

Peripheral vascular disease is often complicated with ischemic heart disease and is associated with increased cardiac mortality. Latent progression of sclerotic changes in the arteries supplying the lower extremities is often present but undiagnosed. We examined the influence of sclerotic changes of the iliac arteries on the late outcome in 79 patients with ischemic heart disease. Lower abdominal aortography was performed at the time of cardiac catheterization between December 1989 and January 1991. The degree of sclerotic change in the iliac arteries was assessed according to aortography findings such as stenosis, dilatation or bend, with higher scores representing more advanced sclerosis (aortography score). The mean aortography score of all patients was 5.8 +/- 4.6. The patients were followed up for 4.4 +/- 1.2 years to monitor the occurrence of cardiac events (cardiac death, acute myocardial infarction, coronary bypass surgery, or coronary angioplasty for new lesion). The cardiac event-free rate at 5 years was 76.6% in the high score group (32 patients with scores of 6 or more) and 92.9% in the low score group (47 patients with scores of 5 or less). The difference was significant (p = 0.007) by log-rank test. The hazard rate of the aortography score for predicting risk of cardiac event was 1.11 by the Cox proportional hazards model (95% confidence intervals: 1.01-1.23, p = 0.039). When the analysis was adjusted for coronary bypass surgery as primary therapy, the number of diseased coronary arteries, or the presence of peripheral vascular disease, similar results were obtained. In conclusion, more severe sclerotic change in iliac arteries is associated with a higher incidence of cardiac events in patients with ischemic heart disease.

Bul1, a new protein that binds to the Rsp5 ubiquitin ligase in Saccharomyces cerevisiae

We characterized a temperature-sensitive mutant of Saccharomyces cerevisiae in which a mini-chromosome was unstable at a high temperature and cloned a new gene which encodes a basic and hydrophilic protein (110 kDa). The disruption of this gene caused the same temperature-sensitive growth as the original mutation. By using the two-hybrid system, we further isolated RSP5 (reverses Spt- phenotype), which encodes a hect (homologous to E6-AP C terminus) domain, as a gene encoding a ubiquitin ligase. Thus, we named our gene BUL1 (for a protein that binds to the ubiquitin ligase). BUL1 seems to be involved in the ubiquitination pathway, since a high dose of UBI1, encoding a ubiquitin, partially suppressed the temperature sensitivity of the bul1 disruptant as well as that of a rsp5 mutant. Coexpression of RSP5 and BUL1 on a multicopy plasmid was toxic for mitotic growth of the wild-type cells. Pulse-chase experiments revealed that Bul1 in the wild-type cells remained stable, while the bands of Bul1 in the rsp5 cells were hardly detected. Since the steady-state levels of the protein were the same in the two strains as determined by immunoblotting analysis, Bul1 might be easily degraded during immunoprecipitation in the absence of intact Rsp5. Furthermore, both Bul1 and Rsp5 appeared to be associated with large complexes which were separated through a sucrose gradient centrifugation, and Rsp5 was coimmunoprecipitated with Bul1. We discuss the possibility that Bul1 functions together with Rsp5 in protein ubiquitination.