Analysis of skin disposition of flurbiprofen after topical application in hairless rats

Cutaneous disposition of topically applied flurbiprofen (FP) was evaluated using a new in situ experimental model in hairless rats. A disk-shaped agar gel (3.85 cm in diameter and 0.5 cm in thickness) was subcutaneously implanted in the abdominal region of rats as a drug receptor, and a drug donor cell was subsequently placed above this agar gel. No significant pharmacokinetic modification of FP was observed as a result of this experimental procedure. A bolus injection and a constant intravenous infusion of FP were applied to the rats, followed by an analysis of FP levels in the plasma and agar gels. Using these results, the clearance rate of FP from the systemic circulation to the gel could be calculated. FP (1% gel formulation, 1.0 g/3.14 cm(2)) was then topically applied to the skin of these rats. From these experiments, the amount of FP that migrated from the formulation to the systemic circulation and the amount of FP that migrated directly to the agar gel across the skin, over 10 h, were separately evaluated to be 235.4 and 2.0 microg, respectively. Thus, most of the FP was absorbed into the systemic circulation. The effect of endogeneous vasoactive compounds and penetration enhancers on the FP disposition within skin was also determined. Epinephrine and bradykinin were used as vasoactive compounds that were entrapped in agar gel, and an isopropyl myristate system (IPM system) and a l-menthol-ethanol-glycerin-water system (MEGW system) were used as enhancers in the formulation. Epinephrine enhanced the direct delivery of FP into the agar gel to more than ten times its former level, in spite of the fact that it had no effect on systemic delivery. Bradykinin strengthened systemic delivery slightly, without changing the quantity of FP in the gel. IPM increased only the systemic delivery of FP, as was the case with bradykinin, whereas the MEGW system markedly increased both the blood concentration and the quantity of FP in the gel (13 and 200 times, respectively). This technique has proven to be an effective tool for the quantitative evaluation of cutaneous disposition of a topically applied drug.

Simultaneous transport and metabolism of ethyl nicotinate in hairless rat skin after its topical application: the effect of enzyme distribution in skin

An in vitro permeation study of ethyl nicotinate (EN) was carried out using excised hairless rat skin, and simultaneous skin transport and metabolism of the drug were kinetically followed. Fairly good steady-state fluxes of EN and its metabolite nicotinic acid (NA) through the skin were obtained after a short lag time for all the concentrations of EN applied. These steady-state fluxes were not proportional to the initial donor concentration of EN: EN and NA curves were concave and convex, respectively, which suggests that metabolic saturation from EN to NA takes place in the viable skin at higher EN application. Further permeation studies of EN or NA were then carried out on full-thickness skin or stripped skin with an esterase inhibitor to measure their permeation parameters, such as partition coefficient of EN from the donor solution to the stratum corneum and diffusion coefficients of EN and NA in the stratum corneum and the viable epidermis and dermis. Separately, enzymatic parameters (Michaelis constant K(m) and maximum metabolism rate V(max)) were obtained from the production rate of NA from different concentrations of EN in the skin homogenate. The obtained permeation and enzymatic parameters were then introduced to differential equations showing Fick's second law of diffusion in the stratum corneum and the law with Michaelis-Menten metabolism in the viable epidermis and dermis. The calculated steady-state fluxes of EN and NA by the equations were very close to the obtained data. We then measured the esterase distribution in skin microphotographically using fluorescein-5-isothiocyanate diacetate. A higher enzyme concentration was observed in the epidermal cells and near hair follicles than in the dermis. Simulation studies using the even and the partial enzyme distribution models suggested that no significant difference between the models was observed in the skin permeations of EN and NA, whereas concentration-distance profiles of EN and NA were very different. This finding suggests that the total amount of enzyme in skin which converts EN to NA is a determinant of the metabolic rate of EN in skin. The present approach is a useful tool for analyzing simultaneous transport and metabolism of many drugs, especially those showing Michaelis-Menten type-metabolic saturation in skin.

Tissue factor and tissue factor pathway inhibitor levels during and after cardiopulmonary resuscitation

Disseminated intravascular coagulation frequently occurs after global ischemia and reperfusion due to cardiac arrest. The present study was performed to demonstrate the role of tissue factor for coagulation pathway activation, as well as to investigate the precise time course of tissue factor pathway inhibitor (TFPI) during and after cardiopulmonary resuscitation (CPR). Thirty-two of out-of-hospital cardiac arrest patients were classified into two groups, those who achieved return of spontaneous circulation (ROSC) (n=13) and those without ROSC (n=19). Ten normal healthy volunteers served as control subjects. Serial levels of tissue factor and TFPI were measured during and after cardiac arrest and CPR. In patients with ROSC, cardiac arrest and CPR led to persistent increases in the levels of tissue factor that peaked 6 hours after arrival at the Emergency Department. Tissue factor levels in patients without ROSC also showed marked elevations compared to those of the control subjects. In both groups, the levels of TFPI were significantly lower than those in the control subjects. However, we could not find differences in the levels of the two markers between the patients with ROSC and those without ROSC. In conclusion, we demonstrated persistent elevation of the tissue factor levels associated with low TFPI during and after CPR in patients with out-of-hospital cardiac arrest. These results indicate the activation of the extrinsic coagulation pathway without adequate TFPI generation, which may contribute to thrombin activation and fibrin formation after whole-body ischemia and reperfusion.

Modulatory effect of a serine protease inhibitor on surgical stress: its clinical implications

The relationship between endogenous cytokine antagonists and surgical stress is poorly understood. Surgical stress induces immunosuppression, and the reversed therapy of postoperative immunosuppression has been expected. The aim of the present study was to assess the effect of a serine protease inhibitor on postoperative immune reactivity. Twenty patients with colorectal cancer were randomly separated into experimental and control groups of 10 patients each. The experimental group received perioperative administration of a serine protease inhibitor while the control group did not. Plasma levels of cytokine antagonists, which suppress cell-mediated immunity, such as cortisol, interleukin-1 receptor antagonist, soluble interleukin-2 receptor (sIL-2R) and soluble tumor necrosis factors p55, p75 (sTNF-R55, -R75) were simultaneously measured. Significant reductions of plasma concentration of sIL-2R and sTNF-R55 were observed. Perioperative administration of a serine protease inhibitor may contribute to ameliorating immunosuppression after major surgery.

Evaluation of bile acids and fusidate derivative as nasal absorption enhancers using an electrophysiological technique

The present study was carried out to investigate the reversibility of the action of two nasal absorption enhancers, bile acids and fusidate derivative, on nasal membrane resistance. The nasal mucosa was isolated from rabbit nasal septum and mounted in a Ussing-type chamber to allow the monitoring of the membrane resistance and flux of fluorescein isothiocyanate-labeled dextran (FD10, M.W. 9400). Membrane resistance was reduced by 46% following treatment with 0.5% (w/v) sodium taurodihydrofusidate (STDHF) for 10 min and then gradually returned to the control level after being wash. The resistance was restored to 76% of the control level following a 30 min treatment with 0.5% (w/v) STDHF. However, there was no recovery of resistance following treatment with 0.5% (w/v) STDHF for 120 min or 1% (w/v) STDHF for 10in. Concurrently, FD10 transport was enhanced while membrane resistance was reduced. Treatment with 0.5% (w/v) sodium deoxycholate (DC) for more than 10 min showed no reversible action and marked FD10 transport enhancement, whereas a 10-30 min treatment with 0.5% (w/v) sodium glycocholate (GC) or sodium taurocholate (TC) resulted in the rapid recovery of membrane resistance without any enhancement of FD10 permeation. STDHF transport across the nasal mucosa was approximately 2-fold faster than that of DC, GC, and TC. The accumulation of STDHF in the nasal mucosa was 2-fold lower than that of DC and 1.7-fold higher than that of GC and TC after a 30 min treatment. The rank order of hydrophobicity determined by reverse-phase HPLC was: DC>STDHF>GC>TC. These results suggest that the reduction in membrane resistance and its reversibility appear to be due to a balance between the accumulation and clearance of STDHF.

Systemic activation of tissue-factor dependent coagulation pathway in evolving acute respiratory distress syndrome in patients with trauma and sepsis

BACKGROUND

Extravascular coagulation and fibrin deposition coupled with perturbations of intravascular coagulation occurs in association with acute respiratory distress syndrome (ARDS). To evaluate the pathogenetic role of an extrinsic coagulation pathway in the intravascular coagulation of ARDS patients and to explore the time course of the changes of tissue factor levels, platelet counts, and disseminated intravascular coagulation (DIC), we performed a prospective cohort study.

METHODS

The study subjects consisted of 113 patients: 27 patients with ARDS, 31 patients at risk for but not developing the syndrome, and 55 patients without ARDS. According to the underlying disease, the patients were further subdivided into two groups: patients with trauma (n = 76) and patients with sepsis (n = 37). Ten normal healthy volunteers served as control subjects. Plasma tissue factor antigen (tissue factor) levels and platelet counts were measured on the day of admission and on days 1 through 4 after admission. Simultaneously, the DIC scores were determined.

RESULTS

The values of tissue factor in the patients with ARDS were significantly more elevated than those measured in the other two groups (p < 0.001) and control subjects (p < 0.001) on the day of admission. The values continued to be markedly high up to day 4 of admission. On the day of admission, the platelet counts in the ARDS patients showed significantly lower values (p < 0.05) than those in the other two groups. The incidence of DIC and the DIC scores in ARDS patients were significantly higher than those in the other two groups. The tissue factor levels (r(s) = 0.428, p < 0.0001) and DIC scores (r(s) = 0.357, p < 0.0002) correlated significantly with Lung Injury Score. When the patients were subdivided into two subgroups, i.e., trauma and sepsis, some differences of the tissue factor levels were noted between the two groups.

CONCLUSION

We demonstrated that tissue-factor dependent coagulation pathway of plasma is extensively activated in patients with ARDS, followed by intravascular coagulation and platelet consumption. We further provide precise information on the time course of tissue factor levels and DIC in patients with ARDS and those at risk for developing this syndrome.

[The anesthetic management of a patient with a congenital mediastinal cyst undergoing video-assisted thoracoscopic surgery (VATS)]

We recently conducted video-assisted thoracoscopic surgery (VATS) on an 8-day-old boy in whom a congenital mediastinal cyst had caused obstruction of the left main bronchus. After the surgery, the cyst recurred and caused reobstruction of the airway. When he was 51-day-old, we conducted VATS again. We could not perform cystectomy by VATS because the left lung was inflated, and we conducted cystectomy by thoracotomy.

A new mode of B12 binding and the direct participation of a potassium ion in enzyme catalysis: X-ray structure of diol dehydratase

BACKGROUND

Diol dehydratase is an enzyme that catalyzes the adenosylcobalamin (coenzyme B12) dependent conversion of 1,2-diols to the corresponding aldehydes. The reaction initiated by homolytic cleavage of the cobalt-carbon bond of the coenzyme proceeds by a radical mechanism. The enzyme is an alpha2beta2gamma2 heterooligomer and has an absolute requirement for a potassium ion for catalytic activity. The crystal structure analysis of a diol dehydratase-cyanocobalamin complex was carried out in order to help understand the mechanism of action of this enzyme.

RESULTS

The three-dimensional structure of diol dehydratase in complex with cyanocobalamin was determined at 2.2 A resolution. The enzyme exists as a dimer of heterotrimers (alphabetagamma)2. The cobalamin molecule is bound between the alpha and beta subunits in the 'base-on' mode, that is, 5,6-dimethylbenzimidazole of the nucleotide moiety coordinates to the cobalt atom in the lower axial position. The alpha subunit includes a (beta/alpha)8 barrel. The substrate, 1,2-propanediol, and an essential potassium ion are deeply buried inside the barrel. The two hydroxyl groups of the substrate coordinate directly to the potassium ion.

CONCLUSIONS

This is the first crystallographic indication of the 'base-on' mode of cobalamin binding. An unusually long cobalt-base bond seems to favor homolytic cleavage of the cobalt-carbon bond and therefore to favor radical enzyme catalysis. Reactive radical intermediates can be protected from side reactions by spatial isolation inside the barrel. On the basis of unique direct interactions between the potassium ion and the two hydroxyl groups of the substrate, direct participation of a potassium ion in enzyme catalysis is strongly suggested.

Forearm heating band used in apheresis therapy that employs a positive-temperature coefficient polymer heater

For standard apheresis therapy, blood is withdrawn from the ante-cubital vein of one arm and processed blood is returned to a vein of the opposite arm. For low-density lipoprotein apheresis or for the treatment of patients with Guillain-Barré syndrome, a sufficient quantity of blood is readily obtained by this method. In some patients with collagen diseases, however, it may be difficult to secure a reliable vein due to vasospasm or it may not be possible to obtain sufficient blood flow. We constructed a forearm heating band by employing a positive-temperature coefficient heater and evaluated the device to determine whether the application of heat to the forearm is effective in securing a sufficient quantity of blood in those patients with collagen disease (eight with systemic lupus erythematosus and one with multicentric Castleman's disease). Both forearms were heated by using this heating band, in addition to systemic warming with an electric blanket, starting 30 minutes before apheresis. The body surface temperature was sequentially monitored by employing a needle-type thermometer. The surface temperature of the heated area became constant at 37.6+/-0.3 degrees C within approximately 20 minutes (34.7+/-1.3 degrees C at the control site, P<0.001). It was found that this heating band makes it possible to obtain the quantity of blood that is necessary for apheresis and reduce the time required for the treatment. No adverse effects attributable to heating of the forearm were recognized.

Screening of cationic compounds as an absorption enhancer for nasal drug delivery

Several cationic compounds were screened as potential nasal absorption enhancers to increase intranasal absorption of a model drug, fluorescein isothiocyanate labeled dextran (MW 4.4 kDa, FD-4), without nasal membrane damage in rats. Their effects were compared with those of classical enhancers. Various cationic compounds (poly-L-arginines with different molecular weights (MW 8.9, 45.5 and 92.0 kDa, poly-L-Arg (10), (50) and (100), respectively), L-arginine (L-Arg), L-lysine (L-Lys), and cetylpyridinium chloride (CPCL) were evaluated. Of the cationic compounds, poly-L-Arg and CPCL greatly enhanced the intranasal absorption of FD-4, as did chitosan, a cationic polysaccharide which has been reported to show a great effect on the transnasal delivery of peptide and protein drugs. The enhancing intensity by poly-L-Arg was dependent on its molecular weight. Rank order of the enhancing ratio, calculated from the AUC ratio for the enhancer treatment against the untreatment, was 0.5% poly-L-Arg (100) congruent with0.5% sodium dodecylsulfate congruent with0.5% CPCL?0.5% poly-L-Arg (50)?0.5% sodium deoxycholate congruent with0.5% sodium taurodihydrofusidate?0.5% polyoxyethylene-9-lauryl ether congruent with0.5% lysophosphatidylcholine?0.5% chitosan congruent with0.5% poly-L-Arg (10)>/=10% L-Arg congruent with10% L-Lys?0.5% sodium glycocholate congruent with0.5% sodium taurocholate congruent with0.5% EDTA. Only the poly-L-Args represented almost the same degree of hemolysis of cationic compounds compared with pH 7.0 phosphate buffered saline in the rat erythrocyte lysis experiment. The enhancing ratio by classical enhancers correlated with leaching of protein, phospholipids and LDH from isolated rabbit nasal mucosa. CPCL also fell on the regression lines between the enhancing ratio and their degree of leaching from classical enhancers. In contrast, the enhancing intensities by poly-L-Arg (10), (50) and (100) were greatly shifted from the regression line: the amount of leaching was markedly low in spite of a great enhancement of FD-4 absorption. These findings suggest that of the assessed enhancers only the poly-L-Args enhance the transnasal delivery of high molecular substances without severe damage to the nasal mucosal membrane. Poly-L-Arg is therefore a promising candidate having a good balance between enhancing activity and safety for nasal peptide and protein delivery.

Binding affinity of sarpogrelate to 5-HT(2A) receptor ligand recognition sites in rat renal cortical and mesangial cells in culture

We detected specific binding of 3H-ketanserin (0.6 nM) in rat renal cortical membrane preparations (4.70 +/- 0.57 fmol/mg protein) and mesangial cells (7.55 +/- 0.92 fmole/10(6) cells). Thus, the value in the renal cortical membrane corresponded to 15% of that in the cerebral cortical membranes (30.0 +/- 2.9 fmole/mg protein). The affinity of 3H-ketanserin binding displacement activities by sarpogrelate, a selective 5-HT2A receptor antagonist, in the renal cortical membrane (IC50; 0.448 +/- 0.061 microM) and mesangial cells (IC50; 0.656 +/- 0.187 microM) were almost 100-fold less than that in the cerebral cortical membrane (IC50; 4.62 +/- 1.02 nM). In the renal cortical membranes and mesangial cells, methysergide displaced a tiny fraction of 3H-ketanserin binding at concentrations up to 10 microM. These results did not explain the functional activity of 5-HT in the mesangial cells, and we conclude that specific 3H-ketanserin binding sites in the mesangial cells consisted of methysergide-resistant and non-serotonergic sites with low affinity for sarpogrelate.

Effects of mineral fibers on the gene expression of proinflammatory cytokines and inducible nitric-oxide synthase in alveolar macrophages

To determine which parameters are useful for the risk assessment of man-made mineral fibers (MMMFs), we examined the gene expression of interleukin-1 alpha (IL-1 alpha), tumor necrosis factor alpha (TNF alpha), interleukin-6 (IL-6) and inducible nitric-oxide synthase (iNOS) in mineral fiber-exposed alveolar macrophages (AMs). Male Wistar rats were intratracheally exposed to saline or mineral fibers suspended in saline (2 mg of crocidolite, chrysotile, alumina silicate refractory fiber (RF1) or potassium octatitanate whisker (TW)). Bronchoalveolar lavage was performed 4 weeks after the fiber-instillation, and the recovered AMs were stimulated by lipopolysaccharide for 2 or 6 hours. Expression of IL-1 alpha, TNF alpha, IL-6 and iNOS from AMs was observed using reverse transcription-polymerase chain reaction (RT-PCR). The levels of IL-1 alpha and IL-6 mRNA induced by mineral fiber exposure were greatest in AMs exposed to TW, crocidolite, chrysotile and RF1 in that order. However, both gene expression of iNOS and TNF alpha were not elevated in both crocidolite and TW exposure, despite their high pathological potential. These data suggested that IL-1 alpha and IL-6 may be useful indicators for the risk assessment of MMMFs.

Pilocarpine-induced cholinergic sweat secretion compared with emotional sweat secretion in atopic dermatitis

We studied pilocarpine-induced cholinergic sweating, emotional sweating and sympathetic reflex sweating in atopic dermatitis (AD) patients. Secreted sweat was measured both with equipment that continuously records sweat rate and with a filter paper method that measures sweat weight absorbed. Comparison of the two methods revealed that the filter paper method underestimated the sweat secretion in AD patients. While AD patients showed no significant abnormalities in emotional sweating and sympathetic reflex sweating, the duration of pilocarpine-induced sweating was prolonged. The time from the maximal sweat rate until the sweat rate fell to half of the maximal rate was significantly longer in AD patients than in control subjects. In contrast, the time from the beginning of sweat secretion until the maximal sweat rate was not significantly different between AD patients and control subjects. There was no significant difference between AD patients and control subjects in sweat volume secreted in 20 min after pilocarpine iontophoresis. In AD patients, the total sweat volume secreted after pilocarpine iontophoresis was greater than in control subjects, although not significantly. These results suggest that the system of deactivation of pilocarpine-induced sweat secretion is impaired in AD patients whereas the activation system is not altered.

Alterations of soluble L- and P-selectins during cardiac arrest and CPR

OBJECTIVE

To investigate the relationship between cytokines and the inflammatory responses in patients with out-of-hospital cardiac arrest, we examined the changes of cytokines as well as alterations in the markers of neutrophil activation, platelet and endothelial activation, and endothelial injury.

DESIGN

Prospective, cohort study.

SETTING

General intensive care unit of a tertiary care center.

PATIENTS AND PARTICIPANTS

26 out-of-hospital cardiac arrest patients were classified into two groups: those who achieved return of spontaneous circulation (ROSC) (n = 10) and those with no ROSC (n = 16). Eight normal healthy volunteers served as control subjects.

MEASUREMENTS AND RESULTS

Serial levels of soluble L-selectin (sL-selectin), soluble P-selectin (sP-selectin), neutrophil elastase, and soluble thrombomodulin were measured during and after cardiopulmonary resuscitation (CPR). Serial levels of tumor necrosis factor alpha (TNFalpha) and interleukin-1beta (IL-1beta) were also measured. We could not find any elevations in either cytokine during the study period. In both groups, sP-selectin levels were significantly higher than those in control subjects from the time of arrival at the emergency department to 24 h after admission. sL-selectin levels in the two groups were markedly lower compared to those in control subjects at all sampling points. In patients with ROSC, cardiac arrest and CPR led to an increase in the levels of neutrophil elastase and soluble thrombomodulin that peaked 6 h or 24 h after arrival at the emergency department. No statistical differences in the levels of the two selectins, neutrophil elastase, and soluble thrombomodulin between the two groups were found during CPR.

CONCLUSIONS

Out-of-hospital cardiac arrest and CPR induces platelet, neutrophil, and endothelial activation and is associated with endothelial injury. Inflammatory cytokines may not have an important role in human whole-body ischemia-reperfusion injury.

Combined effect of cigarette smoke and mineral fibers on the gene expression of cytokine mRNA

To investigate which parameters are stimulated by mineral fibers and whether cigarette smoke enhanced a fiber-induced response, we examined the level of cytokine mRNA from alveolar macrophages (AMs) and lungs of rats exposed to mineral fibers and cigarette smoke in vivo. Male Wistar rats were given a single intratracheal instillation of 2 mg of Union Internationale Contre le Cancer chrysotile or refractory ceramic fiber (RF1). The animals then inhaled a side stream of smoke 5 days per week for 4 weeks. The expression of manganese superoxide dismutase, inducible nitric oxide synthase (iNOS), basic fibroblast growth factor (bFGF), interleukin-1[alpha] (IL-1[alpha]), interleukin-6 (IL-6), and tumor necrosis factor-[alpha] (TNF[alpha]) mRNA from lipopolysaccharide-stimulated AMs and lungs of rats exposed to mineral fibers and/or cigarette smoke were assessed using semiquantitative reverse-transcriptase polymerase chain reaction. Exposure only to cigarette smoke increased in IL-1[alpha] mRNA levels in AMs. Chrysotile stimulated the expression of IL-1[alpha], TNF[alpha], and IL-6 in AMs, and the expression of bFGF in lungs. RF1 resulted in increased expression of IL-1[alpha] and TNF[alpha] in AMs. Cigarette smoke stimulated the gene expression of iNOS in AMs and IL-6 and bFGF in lungs treated with chrysotile; IL-1[alpha] in AMs and bFGF in lungs did the same in lungs with RF1. Among these cytokines, message levels of IL-1[alpha], iNOS, and bFGF were increased in rats stimulated with mineral fibers, and the stimulating effects of mineral fibers were enhanced by cigarette smoke. Therefore, IL-1[alpha], iNOS, and bFGF would be the possible parameters of the lung remodeling induced by mineral fibers.

Skin disposition of drugs after topical application in hairless rats

Drug fraction transported from a topical formulation on skin to subcutaneous tissues or muscles is dependent on the physicochemical properties of the entrapped drug. Cutaneous disposition of model drugs, antipyrine (ANP), lidocaine (LC) and piroxicam (PXC) as well as flurbiprofen (FP) was thus evaluated in hairless rats in which an agar gel disc was subcutaneously inserted into the abdominal region as a drug receptor and a drug donor cell was placed above it. Time courses of plasma level and agar gel amount were measured after topical application of 50% ANP, 3% LC, 1% PXC and 1% FP in hydroxypropylcellulose gel. Percutaneous absorption clearance of unionized form, CLab* was proportional to true octanol/water distribution coefficient and the order of FP > PXC > LC > ANP, suggesting that skin permeation of the drug was determined mainly by its distribution from the formulation to the skin barrier. PXC, however, had a relatively low flux compared to the other three drugs, probably due to its high molecular weight and melting point. Migration clearance of unionized form from systemic circulation to the subcutaneous agar gel, CLg* was also influenced by the lipophilicity of drugs. On the other hand, fraction from the formulation to the systemic circulation was in the order of PXC > FP > ANP > LC. This fraction was much higher than the direct migration fraction from the formulation to the subcutaneous agar gel. Factors determining for these fractions are still unclear. A drug having a low lipophilicity and a low protein binding, however, had a tendency to have a great targeting ability to the subcutaneous agar gel. In addition, most of the drug in the agar gel was contributed by the direct flow from formulation, not from the systemic circulation. The present in situ experimental method is a useful tool to evaluate skin disposition of drugs. Detailed understanding of the skin disposition of drugs from several formulations will enable the findings of a good drug and formulation candidates.

Association between a focal spared area in the fatty liver and intrahepatic efferent blood flow from the gallbladder wall: evaluation with color Doppler sonography

OBJECTIVE

The purpose of this study was to investigate whether fatty sparing adjacent to the gallbladder fossa is related to efferent blood flow from the gallbladder wall.

SUBJECTS AND METHODS

Color and power Doppler sonography were performed in 80 patients with a fatty liver that appeared as a fine echogenic pattern with considerable deep attenuation on sonography. We analyzed whether color signal appeared around the spared area, the gallbladder wall, or both. Subsequently, when such signal was detected, pulse Doppler analysis of the signal was performed.

RESULTS

Color signal indicating efferent blood flow from the gallbladder wall was detected in 25 (64%) of 39 patients with a focal spared area at the gallbladder fossa and in two (5%) of 41 patients without a focal spared area. This difference was statistically significant (p < .05). The waveform of efferent blood flow signals (n = 25) that were seen within spared areas was continuous in 23 (92%) of 25 patients and was pulsatile in the remaining two patients (8%).

CONCLUSION

Blood flow from the gallbladder wall to areas of the spared liver was frequently revealed by color and power Doppler sonography; therefore, this blood flow may be associated with focal fatty sparing.

Prilocaine induces apoptosis in osteoblastic cells

PURPOSE

To determine whether prilocaine, a local anesthetic, induces apoptosis in osteoblastic cells.

METHODS

After reaching subconfluence, human osteoblastic Saos-2 and MG63 cells and mouse osteoblastic MC3T3-E1 cells were exposed for 48 hr to varying concentrations of prilocaine up to 10 mM and the cytotoxicity of the cells was analyzed by phase-contrast microscopy and WST-1 assay. Saos-2 cells treated for 48 hr with 5 mM prilocaine were stained with Hoechst 33342 and nuclear fragmentation was examined under a fluorescence microscope. DNA was extracted from the cells treated with 5 mM prilocaine and DNA ladder formation (a hallmark of apoptosis) was analyzed by agarose gel electrophoresis.

RESULT

Prilocaine induced cell death in Saos-2 cells in a dose- and time-dependent manner up to the concentration of 10 mM. Marked nuclear condensation and fragmentation of chromatin were observed in the prilocaine-treated cells. DNA ladder formation also was induced by prilocaine treatment. Prilocaine-induced DNA ladder formation was dose-dependent with maximal effect at a concentration of 5 mM and was time-dependent from 12 to 48 hr. DNA ladder formation was also induced by prilocaine treatment in human osteoblastic MG63 cells and mouse osteoblastic MC3T3-E1 cells. Cycloheximide prevented prilocaine-induced apoptosis in Saos-2 cells in a dose-dependent fashion up to 20 microM as determined by WST-1 assay and DNA ladder formation in agarose gel electrophoresis.

CONCLUSION

Osteoblastic cells treated with prilocaine exhibit both morphological and biochemical features indicative of apoptosis. The apoptotic mechanisms involve transcriptional regulation of specific proteins or protein synthesis.

Crystallization and preliminary crystallographic studies of FMN-binding protein from Desulfovibrio vulgaris miyazaki F

The flavin mononucleotide binding protein from Desulfovibrio vulgaris (Miyazaki F) was crystallized using the vapour-diffusion method. The crystal belongs to the monoclinic space group P21 with unit-cell parameters a = 37.2, b = 84.6, c = 41.1 A, beta = 94.1 degrees, contains two molecules per asymmetric unit and diffracts beyond 1.2 A resolution with a synchrotron radiation X-ray source.

[Pulmonary tumor mass aberration into the bronchus of the intact right lung during total left lung resection]

A 77-year-old male with lung cancer underwent a total left lung resection. During surgery, there was no ventilatory trouble such as hypoventilation or hypoxia. However, a mass was found in the right main bronchus by endobronchial fiberscopy before extubation. Because the mass could not be aspirated through the endobronchial fiberscope, we extracted it using basket-foreceps. We speculated that surgical procedures may have caused the tumor mass to move to the bronchus of the contralateral intact lung. Accordingly, fiberscopic examination of the airway before extubation should be mandatory, even if there is no ventilatory trouble during lung resection.

End-tidal carbon dioxide and resuscitation

In this review, we attempted to summarize the effectiveness and the limitation of end-tidal carbon dioxide monitoring during cardiopulmonary resuscitation. End-tidal carbon dioxide can be an indicator of the real return of spontaneous circulation and can also be an indicator of the effectiveness of cardiac massage. We cannot, however, estimate the prognosis of cardiopulmonary resuscitation from the end-tidal carbon dioxide value. We concluded that cardiopulmonary resuscitation should never be abandoned for the sole reason that the end-tidal carbon dioxide value is low.

Cyclosporin in psoriasis: continuous monotherapy versus intermittent long-term therapy

Using two methods (continuous monotherapy and intermittent therapy) for the treatment of psoriasis with cyclosporine, we observed the clinical efficacy and adverse reactions of each treatment method for more than 36 months to evaluate the clinical usefulness of both methods. Thirty-seven cases were analyzed and the following results were obtained: 1) The PASI score evaluated at each visit was maintained between 5 and 10 by both treatment methods and the improvement rate was more than 70%, while there was no difference in the daily dose between the two treatment methods; 2) The period required to achieve remission tended to be prolonged by intermittent therapy, while no change was observed with continuous monotherapy; 3) The period up to relapse tended to become shorter with both treatment methods but this tendency was more marked with intermittent therapy; 4) E-PAP(evaluation for prognosis with averaged PASI) was lower in the continuous monotherapy group and the patients were more satisfied; 5) The incidence of adverse reactions was similar to that reported in previous studies, with no difference between the two treatment methods in this regard; 6) A significant increase in BUN levels was observed in elderly patients; 7) There were only three cases in which the drug was discontinued due to exacerbation and adverse reactions. Based on the above findings, continuous monotherapy seems to be of greater clinical usefulness than intermittent therapy.

Crystallization and preliminary x-ray study of two crystal forms of Klebsiella oxytoca diol dehydratase-cyanocobalamin complex

Two crystal forms of Klebsiella oxytoca diol dehydratase complexed with cyanocobalamin have been obtained and preliminary crystallographic experiments have been performed. The crystals belong to two different space groups, depending on the crystallization conditions. One crystal (form I) belongs to space group P212121 with unit-cell parameters a = 76.2, b = 122.3, c = 209. 6 A, and diffracts to 2.2 A resolution using an X-ray beam from a synchrotron radiation source. The other crystal (form II) belongs to space group P21 with unit-cell parameters a = 75.4, b = 132.7, c = 298.8 A, beta = 91.9 degrees, and diffracts to 3.0 A resolution. For the purpose of structure determination, a heavy-atom derivative search was carried out and some mercuric derivatives were found to be promising. Structure analysis by the multiple isomorphous replacement method is now under way.