The feasible maintenance dose of corticosteroid in Takayasu arteritis in the era of biologic therapy.

Objective: Although biologic agents are used in Takayasu arteritis (TAK), corticosteroids are still the mainstay of treatment. This study aimed to investigate the feasible maintenance dose of prednisolone (PSL) in the biologic therapy era.Method: We enrolled 93 patients with TAK who satisfied the criteria of the American College of Rheumatology and visited our department from 2008 to 2018. The clinical characteristics and PSL dose of the patients were retrospectively evaluated.Results: The mean ± sd maintenance dose of PSL was 5.0 ± 3.0 mg/day. In patients having TAK for > 20 years, PSL discontinuation and drug-free status were achieved in 27.2% and 18%, respectively. Although tapering the PSL dose to 10 mg/day was achieved within 12 months, tapering to 5 mg/day required 10 years. Relapse significantly interfered with the PSL dose reduction. The clinical characteristics of patients with relapse included a lower rate of combination therapy using immunosuppressants. Moreover, biologics were used in > 60% of patients with relapse. Tapering of PSL was significantly possible in patients receiving biologics and additional relapse was observed in 6.3% and 50% of patients with and without biologics, respectively. Such PSL-sparing effect enabled the reduction of the median PSL dose from 10 to 5 mg/day. Steroid discontinuation was achieved in some patients.Conclusions: The use of biologics significantly reduced the PSL dose in relapsed patients. A PSL dose of ≤ 5 mg/day is a feasible target for TAK, especially when biologic agents are used. Nevertheless, corticosteroid discontinuation may also be the target in some patients.

Encapsulated probiotic cells: Relevant techniques, natural sources as encapsulating materials and food applications - A narrative review.

The administration of probiotic microorganisms in adequate amounts is constantly related to health benefits. To promote beneficial effects, these microorganisms must not be affected by exposure to environmental factors and must be able to adhere and colonize the human gastrointestinal tract. Several encapsulation techniques and encapsulating materials are available to produce probiotic particles, however, it is essential that the process must not be aggressive, reducing or preventing injuries and cell losses, besides, the particle properties obtained must be adequate for the proposed purpose. At the same time, the global market for supplements and probiotic foods has been growing significantly, and cell encapsulation appears as an alternative to incorporate probiotics into different food matrices. This review discusses and updates the main techniques, and the traditional and emerging polysaccharides for encapsulation of probiotic cells, as well as the advantages and possibilities of incorporating produced particles into food matrices. Currently, various scientific studies report the use of different encapsulation techniques, such as extrusion, emulsion, spray drying, spray chilling and fluidized bed to encapsulate probiotics properly. The alginate is still widely used to produce probiotic particles, however, there has been a growing interest in its total or partial substitution with others polysaccharides, such as gums, mucilages, prebiotic compounds and microbial exopolysaccharides, which improve the protection and survival of encapsulated cells and allow their incorporation into dairy and non-dairy food products.

Molecular allergen profiling in horses by microarray reveals Fag e 2 from buckwheat as a frequent sensitizer.

BACKGROUND: Companion animals are also affected by IgE-mediated allergies, but the eliciting molecules are largely unknown. We aimed at refining an allergen microarray to explore sensitization in horses and compare it to the human IgE reactivity profiles. METHODS: Custom-designed allergen microarray was produced on the basis of the ImmunoCAP ISAC technology containing 131 allergens. Sera from 51 horses derived from Europe or Japan were tested for specific IgE reactivity. The included horse patients were diagnosed for eczema due to insect bite hypersensitivity, chronic coughing, recurrent airway obstruction and urticaria or were clinically asymptomatic. RESULTS: Horses showed individual IgE-binding patterns irrespective of their health status, indicating sensitization. In contrast to European and Japanese human sensitization patterns, frequently recognized allergens were Aln g 1 from alder and Cyn d 1 from Bermuda grass, likely due to specific respiratory exposure around paddocks and near the ground. The most prevalent allergen for 72.5% of the tested horses (37/51) was the 2S-albumin Fag e 2 from buckwheat, which recently gained importance not only in human but also in horse diet. CONCLUSION: In line with the One Health concept, covering human health, animal health and environmental health, allergen microarrays provide novel information on the allergen sensitization patterns of the companion animals around us, which may form a basis for allergen-specific preventive and therapeutic concepts.

High and pointed type of femoral localized reaction frequently extends to complete and incomplete atypical femoral fracture in patients with autoimmune diseases on long-term glucocorticoids and bisphosphonates.

Once a localized reaction (beaking) was detected, discontinuation of bisphosphonates (BPs) and switching to vitamin D supplementation or teriparatide therapy effectively improved its shape. When the localized reaction was high, of the pointed type, and/or accompanied by prodromal pain, the risks of complete and incomplete atypical femoral fracture increased and consideration of prophylactic fixation for such patients was required. INTRODUCTION: Femoral localized reaction (localized periosteal thickening of the lateral cortex, beaking) is reported to precede atypical femoral fractures (AFFs) and to develop in 8-10% of patients with autoimmune diseases taking BPs and glucocorticoids. The aims of the present study were to retrospectively investigate the shapes of localized reaction to consider how to manage the condition. METHODS: Twenty femora of 12 patients with autoimmune diseases who were on BPs and glucocorticoids exhibited femoral localized reaction. The heights of localized reaction were measured and the shapes classified as pointed, arched, and other. Localized reaction changes were divided into three categories: deterioration, no change, and improvement. A severe form of localized reaction was defined; this was associated with prodromal pain, de novo complete AFF, or incomplete AFF with a fracture line at the localized reaction. RESULTS: The mean height of localized reaction was 2.3 ± 0.8 mm (range, 1.0-3.7 mm) and the pointed type was 35%. Localized reaction was significantly higher (3.3 ± 0.8 vs. 2.1 ± 0.7 mm; p = 0.003) and the pointed type more common (78 vs. 27%; p = 0.035) in those with the severe form of localized reaction. Seven patients with localized reactions discontinued BPs just after localized reaction was detected, but five continued on BPs for 2 years. Localized reaction deterioration was more common in patients who continued than discontinued BPs (100 vs. 29%; p = 0.027). After 2 years, all patients had discontinued BPs and localized reaction did not deteriorate further in any patient. CONCLUSIONS: Once a localized reaction was detected, discontinuation of BPs and switching to vitamin D supplementation or teriparatide therapy effectively improved it. When the localized reaction was high, of the pointed type, and/or accompanied by prodromal pain, the risks of complete and incomplete AFF increased and consideration of prophylactic fixation for such patients was required.

Comparison of neoadjuvant chemotherapy versus upfront surgery with or without chemotherapy for patients with clinical stage III esophageal squamous cell carcinoma.

Neoadjuvant chemotherapy (NAC) and chemoradiotherapy have been shown to extend postoperative survival, and preoperative therapy followed by esophagectomy has become the standard treatment worldwide for patients with esophageal squamous cell carcinoma (ESCC). The Japan Clinical Oncology Group 9907 study showed that NAC significantly extended survival in advanced ESCC, but the survival benefit for patients with clinical stage III disease remains to be elucidated. We compared the survival rates of NAC and upfront surgery in patients with clinical stage III ESCC. Consecutive patients histologically diagnosed as clinical stage III (excluding cT4) ESCC were eligible for this retrospective study. Between September 2002 and April 2007, upfront transthoracic esophagectomy was performed initially and, for patients with positive lymph node (LN) metastasis in a resected specimen, adjuvant chemotherapy using cisplatin and 5-fluororouracil every 3 weeks for two cycles was administered (Upfront surgery group). Since May 2007, a NAC regimen used as adjuvant chemotherapy followed by transthoracic esophagectomy has been administered as the standard treatment in our institution (NAC group). Patient characteristics, clinicopathological factors, treatment outcomes, post-treatment recurrence, and overall survival (OS) were compared between the NAC and upfront surgery groups. Fifty-one and 55 patients were included in the NAC and upfront surgery groups, respectively. The R0 resection rate was significantly lower in the NAC group than in the upfront surgery group (upfront surgery, 98%; NAC, 76%; P = 0.003). In the upfront surgery group, of 49 patients who underwent R0 resection and pathologically positive for LN metastasis, 22 (45%) received adjuvant chemotherapy. In the NAC group, 49 (96%) of 51 patients completed two cycles of NAC. In survival analysis, no significant difference in OS was observed between the NAC and upfront surgery groups (NAC: 5-year OS, 43.8%; upfront surgery: 5-year overall surgery, 57.5%; P = 0.167). Patients who underwent R0 resection showed significantly longer OS than did those who underwent R1, R2, or no resection (P = 0.001). In multivariate analysis using age, perioperative chemotherapy, depth of invasion, LN metastasis, surgical radicality, postoperative pneumonia, and anastomotic leakage as covariates, LN metastasis [cN2: hazard ratio (HR), 1.389; P = 0.309; cN3: HR, 16.019; P = 0.012] and surgical radicality (R1: HR, 3.949; P = 0.009; R2 or no resection: HR, 2.912; P = 0.022) were shown to be significant independent prognostic factors. In clinical stage III ESCC patients, no significant difference in OS was observed between NAC and upfront surgery. Although potential patient selection bias might be a factor in this retrospective analysis, the noncurative resection rate was higher after NAC than after upfront surgery. The survival benefit of more intensive NAC needs to be further evaluated.

Treatment of pressure ulcers in patients with declining renal function using arginine, glutamine and ß-hydroxy-ß-methylbutyrate.

The aim of this study is to examine the efficacy on healing pressure ulcers (PU) of using a supplement combination containing arginine, glutamine and ß-hydroxy-ß-methylbutyrate, which was given to two elderly patients with renal dysfunction. The PU was surgically opened, decompressed and treated by drugs. A half quantity of the defined dose of the supplement combination, with an enteral nutrition product, was administered to the patients twice a day. This combination improved the PUs, with no effect on renal function. This novel finding may provide a nutritional rationale of arginine, glutamine and ß-hydroxy-ß-methylbutyrate for PUs associated with renal dysfunction.

Development of a new wastewater treatment process for resource recovery of carotenoids.

A new wastewater treatment process that involves coagulation, ozonation, and microalgae cultivation has been developed. Here, two challenges are discussed. The first was minimizing phosphorus removal during coagulation in order to maximize algal production. The second was to optimize microalgae cultivation; algal species that grow rapidly and produce valuable products are ideal for selection. Haematococcus pluvialis, which produces the carotenoid astaxanthin, was used. Growth rate, nutrient removal ability, and astaxanthin production of H. pluvialis in coagulated wastewater were investigated. After coagulation with chitosan, the turbidity and suspended solids decreased by 89% ± 8% and 73% ± 16%, respectively. The nitrogen and phosphorus contents of the supernatant remained at 86% ± 6% and 67% ± 24%, respectively. These results indicate that coagulation with chitosan can remove turbidity and SS while preserving nutrients. H. pluvialis grew well in the supernatant of coagulated wastewater. The astaxanthin yield from coagulated wastewater in which microalgae were cultured was 3.26 mg/L, and total phosphorus and nitrogen contents decreased 99% ± 1% and 90% ± 8% (Days 31­35), respectively [corrected].

Comparison of Gd-DTPA-induced signal enhancements in rat brain C6 glioma among different pulse sequences in 3-Tesla magnetic resonance imaging.

BACKGROUND: T1-shortening contrast media are routinely used in magnetic resonance (MR) examinations for the diagnosis of brain tumors. Although some studies show a benefit of 3 Tesla (T) compared to 1.5T in delineation of brain tumors using contrast media, it is unclear which pulse sequences are optimal. PURPOSE: To compare gadopentetate dimeglumine (Gd-DTPA)-induced signal enhancements in rat brain C6 glioma in the thalamus region among different pulse sequences in 3T MR imaging. MATERIAL AND METHODS: Five rats with a surgically implanted C6 glioma in their thalamus were examined. T1-weighted brain images of the five rats were acquired before and after Gd-DTPA administration (0.1 mmol/kg) using three clinically available pulse sequences (spin echo [SE], fast SE [FSE], fast spoiled gradient echo [FSPGR]) at 3T. Signal enhancement in the glioma (E(T)) was calculated as the signal intensity after Gd-DTPA administration scaled by that before administration. Pulse sequences were compared using the Tukey-Kramer test. RESULTS: E(T) was 1.12+/-0.05 for FSE, 1.26+/-0.11 for FSPGR, and 1.20+/-0.11 for SE. FSPGR showed significantly higher signal enhancement than FSE and comparable enhancement to SE. CONCLUSION: FSPGR is superior to FSE and comparable to SE in its ability to delineate rat brain C6 glioma in the thalamus region.

The effect of glucose on the progression of the nuclear maturation of pig oocytes.

The progression of the nuclear maturation of oocytes is a useful marker for the estimation of the subsequent developmental competence of oocytes. In this study, we examined the effect of energy substrates in an in vitro maturation medium on the progression of the nuclear maturation of oocytes. In experiment 1, the supplementation of the maturation medium with 0, 5 and 10 mM of glucose lead to increase in the total cell number of the blastocysts. In experiments 2 and 3, the maturation phase was divided into two stages (germinal vesicle (GV) stage: 0-20 h and nuclear maturation stage: 20-44 h), and the effects of glucose or pyruvate added at each stage on the kinetics of nuclear maturation were examined. The addition of glucose at the nuclear maturation stage rather than at the GV stage of maturation effected greater acceleration in the progression of nuclear maturation. However, the addition of pyruvate at both stages had the same effect on the progression of nuclear maturation was the same. In addition, when glucose was added to the medium containing pyruvate, an additive effect on the progression of nuclear maturation was observed (experiment 4). In experiment 5, the inhibitors of glucose-6-phosphate dehydrogenase (G6PD), dehydroepiandrosterone (DHEA) and 6-aminonicotinamide (6-AN) decreased the rate of the final maturation of oocytes and reduced the difference between the rates of the final maturation of oocytes cultured with glucose and those cultured with pyruvate. In the experiment 6, when the activator of G6PD, brilliant cresyle blue (BCB), was added to the maturation medium, the progression of nuclear maturation was significantly accelerated. The results of this study suggested that in addition to the role of an energy substrate, glucose or its metabolites play a role in nuclear maturation. This role was more pronounced at the second stage of maturation (transition from GV breakdown (GVBD) to M2), probably due to the metabolism of glucose via the pentose phosphate pathway (PPP) rather than the glycolysis pathway.

Modification of ovary stock solution with magnesium and raffinose improves the developmental competence of oocytes after long preservation.

During ovary storage oocytes lose some of their developmental competence. In the present study, we maintained storage solutions of phosphate-buffered saline (PBS) at various temperatures (20 or 35 degrees C) or supplemented them with magnesium (Mg), raffinose and sucrose. Subsequently, we examined the kinetics of electrolytes in the follicular fluid (FF) during the ovary storage period (9 h), the survival rate of granulosa cells in the follicles, and the developmental competence of oocytes after the storage. Lowering the temperature from 35 to 20 degrees C increased the total cell number of blastocysts that developed at 7 days after in vitro maturation and in vitro fertilization of oocytes. In stock solution with supplements of 15 mM Mg or a combination of 5 mM Mg and 10 mM raffinose or sucrose, a significantly higher number of oocytes developed into blastocysts with a large number of cells in each blastocyst, and a significantly higher number of living granulosa cells were obtained as compared with stock solutions without any supplements. During ovary storage, the concentrations of potassium and chloride in the FF were increased, and the addition of Mg to the stock solution increased the concentration of Mg in the FF. Germinal vesicle breakdown in oocytes that were collected from ovaries stored in the solution supplemented with 15 mM Mg or a combination of 5 mM Mg and 10 mM of raffinose occurred at a slower rate than that in oocytes collected from ovaries stored in PBS alone. On the other hand, the oocytes collected from ovaries stored in the solution supplemented with 15 mM Mg or a combination of 5 mM Mg and 10 mM raffinose reached the metaphase II (MII) stage more rapidly than the oocytes collected from ovaries stored in the PBS alone. In conclusion, the modification of stock solution by the addition of Mg and raffinose improved the developmental competence of oocytes obtained from ovaries preserved for a long period.

Mitochondrial DNA decreases during pollen development in rapeseed (Brassica napus L.), but mitochondrial linear-plasmid-encoded RNA polymerase persists in mature pollen.

Mitochondrial DNA in the male reproductive cells of rapeseed (Brassica napus L.) was monitored by fluorescence microscopy of Technovit 7100 resin sections double-stained with 4',6-diamidino-2-phenylindole and 3,3'-dihexyloxacarbocyanine iodide. Mitochondrial DNA progressively decreased during pollen development and disappeared in mature pollen. This result corresponds well with the maternal inheritance of mitochondria in rapeseed determined by previous genetic analyses. To better characterize the mode of inheritance of the mitochondrial linear plasmid in rapeseed, which is transmitted through pollen, we analyzed by indirect immunofluorescence microscopy the expression and localization of ORF6 protein, a putative RNA polymerase encoded by the plasmid. ORF6 protein was expressed in mature pollen and specifically localized in the cytoplasm of sperm cells in the mature pollen. This suggests that the genes encoded by the plasmid DNA are transcribed in the mature pollen by its own RNA polymerase (ORF6 protein) and that the gene expression in the generative cells may be needed for transmission of plasmid DNA through the pollen.

Role of cystine transport in intracellular glutathione level and cisplatin resistance in human ovarian cancer cell lines.

Transport system x(c)(-) is a member of plasma membrane heterodimeric amino-acid transporters and consists of two protein components, xCT and 4F2hc. This system mediates cystine entry coupled with the exodus of intracellular glutamate and regulates the intracellular glutathione (GSH) levels in most mammalian cultured cells. We studied the activity of system x(c)(-) and GSH content in human ovarian cancer cell line (A2780) and its cisplatin (CDDP)-resistant variant (A2780DDP). The rate of cystine uptake was approximately 4.5-fold higher in A2780DDP cells than in A2780 cells and the cystine uptake in A2780DDP cells was mediated by system x(c)(-). Intracellular GSH content was much higher in A2780DDP cells but it fell drastically in the presence of excess glutamate, which inhibited the cystine uptake competitively. xCT and 4F2hc mRNAs were definitely expressed in A2780DDP cells, but far less in A2780 cells. Expression of system x(c)(-) activity by transfection with cDNAs for xCT and 4F2hc made A2780 cells more resistant to CDDP. Similar results on the cystine uptake were obtained in human colonic cancer cell lines. These findings suggest that the system x(c)(-) plays an important role in maintaining the higher levels of GSH and consequently in CDDP resistance in cancer cell lines.

Bile acid extraction rate in the liver of cows fed high-fat diet and lipid profiles in the portal and hepatic veins.

The purposes of this study are to assess the responses of increased supplemental dietary fat in the cow, without upsetting rumen fermentation, on the bile acid (BA) extraction rate in the liver and to determine whether this diet would affect the postprandial lipid profiles in the portal and hepatic venous blood. Six Holstein cows were equipped with catheters fitted in the portal and hepatic veins. Two cows each were assigned randomly to a sequence of three dietary treatments of 21-day period. The methodology of this study was based on the supplementation of the basal concentrate diet with 0 (control), 5, or 10% calcium salts of fatty acids (CSFA). The total bile acids were significantly increased in the portal and hepatic veins with the 5% CSFA diet, whereas no increase occurred with the 10% CSFA diet. Data obtained in this study showed that 10% CSFA diet failed to stimulate BA secretion to exceed the values obtained with 5% CSFA-diet. Moreover, there was no change in the hepatic extraction rate of BA in animals fed either the 0 or 5% CSFA diets which ranged from 2.4 to 6.5-fold and 3.1 to 7.3-fold, respectively. However, the extraction rate increased sharply with the 10% CSFA diet (27-fold). The median portal and hepatic concentrations of total lipids, triglycerides, total cholesterol, phospholipids and non-esterified fatty acids did not show any significant increase during feeding of the control diet. Moreover, feeding either the 5 or 10% CSFA diet did not significantly increase these values in either vein.

Suppression of membrane-type 1 matrix metalloproteinase (MMP)-mediated MMP-2 activation and tumor invasion by testican 3 and its splicing variant gene product, N-Tes.

Using expression cloning to screen a human fetal kidney cDNA library for regulator(s) of pro-matrix metalloproteinase (MMP)-2 processing mediated by membrane-type (MT) 1 MMP, we isolated a cDNA whose product interfered with pro-MMP-2 activation. It encodes the NH(2)-terminal 313-amino acid region of a calcium-binding proteoglycan, testican 3, with a 3-amino acid substitution at the COOH terminus and thus was named N-Tes. N-Tes comprises a signal peptide, a unique domain, a follistatin-like domain, and a Ca(2+)-binding domain but lacks a COOH-terminal thyroglobulin domain and two putative glycosaminoglycan attachment sites of testican 3. Pro-MMP-2 activation by MT3-MMP was also inhibited by the coexpression of N-Tes. Immunoprecipitation analysis demonstrated direct interaction of N-Tes with either MT1-MMP or MT3-MMP. Expression of testican 1 or testican 3 but not testican 2 also inhibited pro-MMP-2 activation by either MT1-MMP or MT3-MMP. Deletion and substitution of amino acids residues in N-Tes revealed that the unique NH(2)-terminal domain of N-Tes is responsible for the inhibition of pro-MMP-2 activation by MT-MMPs. Expression of N-Tes and testican 3 was detected in normal brain but down-regulated in glioma tissues. Transfection of either the N-Tes or testican 3 gene into U251 glioma cells or Madin-Darby canine kidney cells transformed by erbB2 suppressed their invasive growth in collagen gel. These results suggest that both N-Tes and testican 3 would interfere with tumor invasion by inhibiting MT-MMPs.

Dicationic dithiocarbamate carbapenems with anti-MRSA activity.

A new class of 1 beta-methylcarbapenems bearing a doubly quaternarized 1,4-diazabicyclooctane (DABCO) substituted dithiocarbamate moiety at the C-2 side chain was prepared, and the biological profiles of the compounds, including in vitro and in vivo anti-MRSA activity and DHP-I susceptibility, were evaluated to identify a carbapenem derivative that was superior to BO-3482 (1). As a result, we discovered a 1 beta-methyl-2-[4-(4-carbamoylmethyl-1,4-diazabicyclo[2,2,2]octanediium-1-yl)methyl-1,2,3,6-tetrahydropyridinylthiocarbonylthio]carbapenem, 14a showing greater than 2-fold better anti-MRSA activity in a mouse infection model and 3-fold better DHP-I susceptibility as compared with BO-3482 (1).

Molecular cloning and characterization of CHM1L, a novel membrane molecule similar to chondromodulin-I.

Chondromodulin-I (ChM-I) is a cartilage-specific glycoprotein that stimulates the growth of chondrocytes and inhibits the tube formation of endothelial cells. In the present study, we identified a novel ChM-I like molecule, designated ChM1L. Cloning of full length cDNAs of human, mouse, and rat ChM1L revealed that ChM1L encodes 317 amino acids novel type II transmembrane protein. ChM1L protein was expressed on the cell surface as N-glycosylated and non-N-glycosylated protein with molecular mass of 45 and 40 kDa, respectively. In adult mouse tissues, ChM1L mRNA was highly expressed in eye, skeletal muscle, and whole rib. The temporal pattern of ChM1L mRNA was examined using whole embryo at day 10 to 19 of gestation. After day 11, ChM1L mRNA was detected and its level was progressively elevated in association with development of mouse embryo. These data suggest that ChM1L is a novel membrane molecule which is similar to ChM-I that plays a regulatory role in eye, skeletal muscle, and development of embryo.

Otolith-activated vestibulothalamic neurons in cats.

The components of the vestibular ascending pathway that transmit otolith information to the thalamus were studied electrophysiologically in anesthetized cats. Thalamic-projecting vestibular neurons (confirmed antidromically) were recorded extracellularly in the various vestibular nuclei. Otolith inputs to these neurons were examined with selective stimulation of the utricular (UT) or the saccular (SAC) nerves. Vestibular nerve branches other than the tested nerve were transected. Of 40 UT-activated vestibulothalamic neurons, 40% (16/40) were activated by UT nerve stimulation with latencies ranging between 0.9-1.4 ms, suggesting they were second-order neurons from the UT nerve. UT-activated vestibulothalamic neurons were recorded in the medial vestibular nucleus (MVN; 24/40), the lateral vestibular nucleus (LVN; 9/40), the descending vestibular nucleus (DVN; 6/40), and the superior vestibular nucleus (SVN; 1/40). Most of the neurons (38/40) were antidromically activated by focal stimulation of the ventral part of the ipsilateral thalamus. Antidromic stimulation of the pontine area revealed that trajectories of the ascending axons (14 of 38 neurons) to the ipsilateral thalamus passed through the pontine reticular formation, ventral to the ascending tract of Deiters (ATD) and the medial longitudinal fasciculus (MLF). Only three SAC-activated vestibulothalamic neurons were encountered in the LVN. All these neurons were second-order neurons from the SAC nerve and were antidromically activated by stimulation of the contralateral thalamus, in marked contrast to the UT-activated vestibulothalamic neurons. Only three UT-activated and two SAC-activated neurons sent descending collaterals to the spinal cord.

Effects of nifedipine retard on heart rate and autonomic balance in patients with ischemic heart disease.

The aim of this study was to explore the effects of nifedipine retard on heart rate and autonomic balance in patients with ischemic heart disease. Fourteen patients with ischemic heart disease (12 men and two women; mean age 64 years) were administered nifedipine retard at a daily dose of 20-40 mg. Changes in heart rate and autonomic balance were studied using Holter monitoring before and after 12 weeks of nifedipine therapy Heart rate was unchanged during sleep but was higher during the day after nifedipine retard administration. The high frequency power spectrum of heart rate variability (indicating parasympathetic activity) was lower during the day after nifedipine retard therapy but was unchanged during sleep. The low frequency power to high frequency power ratio, indicating sympathetic activity was unchanged during the day and during sleep. Nifedipine retard increased the heart rate of patients with ischemic heart disease only during the day and reduced parasympathetic activity.

Quantitative relationship between myocardial concentration of tacrolimus and QT prolongation in guinea pigs: pharmacokinetic/pharmacodynamic model incorporating a site of adverse effect.

Clinical cases have been reported of tacrolimus (FK506)-induced QT prolongation. We have previously demonstrated sustained QT prolongation by FK506 in guinea pigs. Herein, we aimed to conduct a pharmacokinetic/pharmacodynamic (PK/PD) analysis of FK506, using a model involving the myocardial compartment. The pharmacokinetics of FK506 and its effects on QTc intervals were investigated in guinea pigs. In the pharmacokinetic study, whole blood and ventricular FK506 concentrations were analyzed, using a 4-compartment model during and after intravenous infusion of FK506 (0.01 or 0.1 mg/hr/kg). Subsequently, the concentration-response relationship between ventricular FK506 concentration and change in QTc interval was analyzed, using the maximal effect (Emax) model. Pharmacokinetic profiles of FK506 showed a delayed distribution of FK506 into the ventricle. Furthermore, the observed QT prolongation paralleled the ventricular FK506 concentrations, with no lag-time between the two. The Emax model successfully described the relationship between changes in QTc interval and ventricular FK506 concentrations. In conclusion, the PK/PD model where the myocardial drug concentration of FK506 was linked with its adverse effect could describe, for the first time, the anti-clockwise hysteresis observed in the relationship between blood FK506 concentration and QTprolongation. Such a hysteresis pattern for QTprolongation might be caused, therefore, mainly by the delayed disposition of FK506 to ventricular myocytes.