Two-Dimensional NMR Study of a Liquid-Crystal Solution under Magic-Angle Spinning. Conformation of Carboxylic Ionophore Lasalocid A Dissolved in a Lyotropic Liquid Crystal

The conformation of a carboxylic ionophore, lasalocid A, has been determined in a lyotropic liquid crystal by means of magic-angle spinning (MAS) and two-dimensional NMR experiments. The information extracted from ROESY spectra measured under MAS was analyzed according to the distance-geometry algorithm. The liquid crystal used for the solvent is cesium perfluorooctanoate dissolved in D2O, and the resulting structure of lasalocid A is a cyclic one, indicating cation complexation within a hydrophobic region of the liquid crystal. In this way, the two-dimensional MAS NMR experiment is proved to be a useful technique in conformational studies of complex molecules dissolved in lyotropic liquid crystal which may be regarded as offering a membrane-like environment.

A novel kinase cascade mediated by mitogen-activated protein kinase kinase 6 and MKK3

A cDNA encoding a novel member of the mitogen-activated protein kinase kinase (MAPKK) family, MAPKK6, was isolated and found to encode a protein of 334 amino acids, with a calculated molecular mass of 37 kDa that is 79% identical to MKK3. MAPKK6 was shown to phosphorylate and specifically activate the p38/MPK2 subgroup of the mitogen-activated protein kinase superfamily and could be demonstrated to be phosphorylated and activated in vitro by TAK1, a recently identified MAPKK kinase. MKK3 was also shown to be a good substrate for TAK1 in vitro. Furthermore, when co-expressed with TAK1 in cells in culture, both MAPKK6 and MKK3 were strongly activated. In addition, co-expression of TAK1 and p38/MPK2 in cells resulted in activation of p38/MPK2. These results indicate the existence of a novel kinase cascade consisting of TAK1, MAPKK6/MKK3, and p38/MPK2.

Inhibition of purified human sucrase and isomaltase by ethanolamine derivatives

Sucrase-isomaltase complex was purified from human intestinal mucosa. Immunostaining shows that sucrase-isomaltase is confined to the area of the striated cell borders of human small intestinal absorptive cells of the villus. Inhibition of sucrase and isomaltase activity by ethanolamine derivatives was investigated. Tris inhibits both types of enzyme activity and is the strongest inhibitor of the ethanolamine derivatives investigated. Bis-Tris inhibited sucrase more than isomaltase. On the other hand, mono-, di- and tri-ethanolamine were weak inhibitors of sucrase but not isomaltase.

[Intraoperative use of plasma-derived activated factor VII (F VII a) in a hemophilia A patient with inhibitors]

We treated a 1-year 9-month-old boy with severe hemophilia A who developed high level of F VIII inhibitor. A placement of an implantable intravenous access device was scheduled under general anesthesia. After a slow induction using oxygen, nitrous oxide and sevoflurane, a peripheral venous line was placed and plasma-derived F VII a was infused. A catheter was inserted via the jugular vein to the SVC and it was connected to the device placed subcutaneously in his right chest wall. The peroperative blood loss was slight, and anesthesia and surgery went uneventfully.

Novel designed enediynes: molecular design, chemical synthesis, mode of cycloaromatization and guanine-specific DNA cleavage

The molecular design and chemical synthesis of novel enediyne molecules related to the neocarzinostatin chromophore (1), and their chemical and DNA cleaving properties are described. The 10-membered enediyne triols 16-18 were effectively synthesized from xylitol (10) in a short step, and found to be quite stable when handled at room temperature. The representative and acylated enediyne 16 was cycloaromatized by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in cyclohexa-1,4-diene-benzene to give the benzenoid product 21 through a radical pathway. On the other hand, the enediyne 16 was cycloaromatized by diethylamine in dimethyl sulfoxide-Tris-HCl, pH 8.5 buffer to afford another benzenoid product 22 as a diethylamine adduct through a polar pathway. Furthermore, the enediynes 16-18 were found to exhibit guanine-specific DNA cleavage under weakly basic conditions with no additive.

The effect of a perioperative steroid pulse on surgical stress in hepatic resection

Little has been reported on the control of cytokine release, which is induced by surgical stress. The aim of this study was to investigate the effect of a perioperative short-term steroid pulse on surgical stress. Seventeen patients with a non-cholestatic liver, who underwent hepatic resection, were included in this study. The patients were classified into two groups consisting of a control group (n = 11) and a steroid pulse group (n = 6), in whom 30 mg/kg of methylprednisolone was intravenously administered 3 hours before the operation, and thereafter 1 gram of methylprednisolone was also intravenously administered both immediately after operation and on postoperative day 1. Interleukin 6 was serially measured, and the perioperative clinical parameters including C-reactive protein were compared between both the control and the steroid pulse groups. The IL-6 values immediately after operation, as well as at postoperative days 1 and 3 in the steroid pulse group were significantly lower than those in the control group. The value of the C-reactive protein at postoperative day 3 in the steroid pulse group was significantly lower than that in the control group, and the postoperative peak value of bilirubin as well as the incidence of postoperative complications in the control group tended to be higher than those in the steroid pulse group. In addition, the steroid pulse demonstrated no adverse side effects. A perioperative short-term steroid pulse using methylprednisolone is thus suggested to reduce surgical stress by decreasing cytokine release.

Cystic neoplasms of the liver: a report of two cases with special reference to cystadenocarcinoma

We herein present two cases with cystic neoplasms of the liver, both successfully treated by a surgical resection. One patient underwent a tumor enucleation, while the other had a left hepatic lobectomy and left caudate lobectomy. Although the follow-up period is still relatively short, both patients are doing well without any sign of recurrence. The specimens were histopathologically examined including immunohistochemical staining. Both tumors were unilocular-cystic and contained mucus. One tumor was considered to have originated from a cystadenoma with a mesenchymal stroma, which has been espoused by Wheeler and Edmondson, while the other tumor was considered to have originated from the bile duct. Therefore, the diagnosis of one patient was cystadenocarcinoma, while the other was considered to be a mucin-producing papillary adenocarcinoma of the intrahepatic bile duct. No invasive growth to the liver parenchyma or the surrounding tissues was observed in either case. Thus, a surgical resection should be the first choice of treatment for cystic neoplasms of the liver. Furthermore, a malignant transformation of cystadenoma with a mesenchymal stroma should be given a special entity in cystadenocarcinoma.

Cocaine-induced CREB phosphorylation and c-Fos expression are suppressed in Parkinsonism model mice

Cocaine exerts multiple neurochemical effects in the central nervous system through inhibition of the dopamine transporter at the synapse. Here we report that systemic administration of the drug induces rapid phosphorylation of CREB in the mouse striatum where expression of the nuclear proto-oncogene c-fos is observed. In MPTP-treated mice, in which dopaminergic neurones are degenerated and which show Parkinsonism-like behaviour, however, CREB phosphorylation is not induced by cocaine exposure and c-fos expression is significantly depressed in comparison with controls. These data suggest that CREB may play a major role in the dopaminergic activation of c-fos in the striatum and that the lack of a CREB-induced transcription cascade may have a critical relevance for long-lasting psychomotor disorders in Parkinsonism.

Poly A-linked non-isotopic microtiter plate reverse transcriptase assay for sensitive detection of clinical human immunodeficiency virus isolates

A colorimetric reverse transcriptase assay (cRT assay) was developed for quantitative detection of HIV-1. In this format, reverse transcriptase incorporates biotin-labeled dUTP onto oligo-dT primers hybridized to poly A templates. The templates are covalently bound to the surface of microtiter wells. The amount of incorporated biotin-labeled dUTP is measured by binding horseradish peroxidase conjugated streptavidin, washing away unbound peroxidase, adding colorimetric substrate and then reading with a standard colorimetric reader. The sensitivity of the assay is very good. As little as 3 x 10(5) molecules of recombinant HIV-RT can be detected after 20 h of reaction time. Direct comparison using 3 cultured clinical isolates indicates that this level of detection is equivalent to the commercially available p24 antigen capture assay and the HIV-RNA assay based on branched DNA signal amplification. Other retroviruses, such as HIV-2 and feline immunodeficiency virus (FIV), can also be detected in this format. This non-isotopic assay is easy to perform and could provide a convenient and quantitative method for HIV study by monitoring reverse transcriptase, an essential activity in the infection process.

[Bupivacaine-fentanyl continuous infusion is superior to morphine bolus injection in postoperative epidural analgesia]

We compared bolus injection of morphine 51 +/- 9 micrograms.kg-1 (M-S group) with 48 h-continuous infusion of bupivacaine and fentanyl mixture (BF-C group) for postoperative epidural analgesia in 100 patients who had undergone upper abdominal laparotomy. The epidural analgesia was started about 60 min before completion of surgery. The mixed solution, consisting of bupivacaine 48 ml (240 mg), fentanyl 24 ml (1.2 mg) and 0.9% saline (24 ml), was administered at a rate of 2 ml.h-1 by using a 100 ml balloon infuser. Analgesic effects (determined by visual analogue scale, verbal pain scores at rest and with movement, additional requests of other analgesics), comfort and side effects of the epidural analgesia were examined. The evaluation based on postoperative analgesia and comfortable feeling rated higher in the BF-C group compared with the M-S group (P < 0.01 to of 0.05). There were fewer requests for other postoperative analgesics in the BF-C group (P < 0.01 to 0.05). There was no significant difference in side effects between the two groups. The plasma fentanyl concentration in the BF-C group (n = 5) was maintained almost constant for the period from 24 to 49 hours after the start of infusion and was approximately 1.6 ng.ml-1. We conclude that continuous infusion of bupivacaine (2.5 mg.ml-1) and fentanyl (12.5 micrograms.ml-1) at a rate of 2 ml.h-1 is superior to bolus injection of morphine for postoperative analgesia.

Needle track seeding after percutaneous ethanol injection therapy for small hepatocellular carcinoma

We present two cases of patients experiencing needle track seeding after undergoing percutaneous ethanol injection therapy (PEIT) for small hepatocellular carcinoma, who were treated by surgical resection of the metastases. One patient demonstrated metastatic tumors due to needle track seeding 6 months after the beginning of PEIT (a total of 7 injection sessions for 2 tumors measuring < 20 mm in diameters), whereas the other developed a metastatic tumor 20 months after beginning PEIT (a total of 30 injection sessions for 3 tumors measuring < 20 mm in diameter). In the two cases, both the primary and metastatic tumors histologically revealed moderately differentiated hepatocellular carcinoma. Moreover, the histological findings of the metastatic foci did not always appear to be more aggressive than those of the primary tumors. Therefore, in order to detect such metastasis as early as possible, more careful attention should be paid to the appearance of needle track seeding after performing PEIT for hepatocellular carcinoma, even if the target of such PEIT is small HCC.

Inhibition of the high-affinity glutamate uptake system facilitates the massive potassium flux during cerebral ischaemia in vivo

During cerebral ischaemia, the extracellular concentration of K+ ([K+]e) increases abruptly to 50-60 mM following an initial slow increase to 6-10 mM. We have recently shown that the increase in [K+]e is significantly delayed by in situ administration of kynurenic acid, a broad spectrum antagonist of excitatory amino acids, suggesting that the catastrophic ionic fluxes occurring during ischaemia are initially mediated by EAA-coupled ion channels. In order to confirm further the role of EAAs, the changes in extracellular K+ ([K+]e) and glutamate ([Glu]e) during cerebral ischaemia were determined in the rat hippocampus by microdialysis in vivo, and the effect of dihydrokainate (DHKA), an inhibitor of the high-affinity uptake system of EAAs, was examined by in situ administration through the dialysis probe. DHKA induced a significant increase in baseline [Glu]e and facilitated the abrupt increase in [K+]e during cerebral ischaemia. These findings support the hypothesis that EAAs play a vital role in producing the rapid ionic shifts earlier during cerebral ischaemia.

Quantitative assessment of the autonomic nervous system activities during atropine-induced bradycardia by heart rate spectral analysis

Using power spectral analysis of heart rate fluctuation, autonomic nervous system activities in bradycardia appearing in the initial phase of atropine administration were evaluated quantitatively in 16 healthy females. Atropine sulfate (10 micrograms/kg), diluted in 100 ml of 0.9% NaCl solution, was intravenously infused at a rate of 0.5 micrograms/kg per min. Electrocardiograms were sampled for 4 min for later analysis before and 0, 5, 10, 15 and 20 min after initiation of atropine infusion. Powers of low (LFC, 0.05-0.15 Hz) and high-frequency (HFC, 0.15-0.4 Hz) components in the power spectrum of R-R interval variations, and the LFC/HFC ratio were determined at each sampling point. HFC power at 0-4 min increased from 1.11 +/- 0.18 ms2 (mean) of baseline value to 1.37 +/- 0.19 ms2 (P < 0.05). The next 5-9-min value of 1.48 +/- 0.14 ms2 was the maximum, and the amount of atropine infused by 9 min was 4.5 micrograms/kg. The HFC powers following this point decreased. The 20-24-min value after 10 micrograms/kg atropine decreased to 0.21 +/- 0.03 ms2 (P < 0.01), which was lower than the previous 15-19-min value of 0.36 +/- 0.04 ms2 (P < 0.01). The LFC/HFC ratios showed no significant change for the initial 9 min of the atropine infusion. However, these ratios at 15-19 min and 20-24 min were increased from 0.50 +/- 0.04 (mean) of baseline value to 0.75 +/- 0.09 and 0.81 +/- 0.09, respectively (P < 0.01). A transient vagotonic state after atropine administration, followed by the well-known vagolytic state, was quantitatively detected by non-invasive spectral analysis of heart-rate fluctuation.

The effects of pituitary adenylate cyclase-activating polypeptide on cerebral arteries and vertebral artery blood flow in anesthetized dogs

We investigated and compared the effects of pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) on cerebral circulation in anesthetized dogs. The intracisternal administration of PACAP-27, PACAP-38, and VIP dilated canine cerebral arteries in a dose-dependent manner. A 10 nmol dose of PACAP-27, PACAP-38, and VIP dilated the basilar artery by 23 +/- 3, 27 +/- 3 and 30 +/- 3%, respectively. Rostrally located arteries tended to be more responsive to PACAP-27. Pretreatment with NG-monomethyl-L-arginine did not affect PACAP-27-induced vasodilation. Vertebral artery blood flow was also affected by intra-arterial injection of these peptides in a dose-dependent manner. A 100 pmol dose of PACAP-27, PACAP-38, and VIP increased the vertebral artery blood flow by 42 +/- 10, 29 +/- 4, and 62 +/- 11%, respectively. The VIP receptor antagonist, [Lys1,Pro2,5,Arg3,4,Tyr6]VIP, inhibited both the VIP- and PACAP-38-induced increase in vertebral artery blood flow. These findings suggest that PACAP plays a role in the regulation of cerebral circulation.

Dye-mixture laser tunable in three primary color regions with a linear variable filter

The tuning characteristics of a Coumarine 460-Disodium Fluorescein-Rhodamine 640 dye-mixture laser in the blue, green, and yellow-orange regions are reported. A linear variable filter was inserted into the laser cavity as a tuning element. The tunable range was 439-485 nm in the blue region, 509-531 nm in the green region, and 592-601 nm in the yellow-orange region. Comparison of the characteristics of the one-wavelength tuning output with those of simultaneous broadband outputs in the three color regions showed that energy transfer was an important mechanism for the oscillations, especially in the longer-wavelength region, which was farthest away from a pumping wavelength.

Genomic analysis of a NF1-related pseudogene on human chromosome 21

A neurofibromatosis type-1 (NF1)-related locus on human chromosome 21 has been characterized. A detailed genomic mapping performed by yeast artificial chromosome (YAC) dot-hybridization revealed that the NF1-related locus is close to the sequence-tagged site (STS), D21S329 (G52E12), which is located on the proximal region of 21q11.2. Sequence analysis showed that this locus seemed to be conserved to the NF1 gene only in several partial regions. Two exon-like segments corresponding to exons 8 and 9 of NF1 were found, in addition to two previously found fragments corresponding to exons 7 and 11. Other exon-like segments were not found in the region so far sequenced. Comparing these homologous segments with the NF1 cDNA, a 2-bp deletion appeared in exon 8 of the locus, resulting in the existence of stop codons in all reading frames. In addition, there were no amplified fragments derived from the related locus by reverse transcription-PCR. Thus, our results suggest that the NF1-related locus on chromosome 21 is a nonprocessed pseudogene.

N-methyl-D-aspartate receptor-mediated, prolonged afterdischarges of CA1 pyramidal cells following transient cerebral ischemia in the rat hippocampus in vivo

We previously reported the post-ischemic potentiation (PIP) of synaptic efficacy in hippocampal Schaffer collateral/CA1 responses of the rat beginning at 6-8 h following 12 min transient cerebral ischemia in vivo. The present study demonstrated that repetitive stimulation with a relatively low frequency (5 Hz, 6 s), which produced short-lasting afterdischarges (ADs; duration, 4.49 +/- 4.26 s; n = 7) in sham-controls, resulted in prolonged ADs (duration, 26.33 +/- 12.63 s; n = 6; P < 0.001) at the same period after ischemia. The PIP was not affected by 2-amino-5-phosphonovalerate (APV) administered via microdialysis at 7 h post-ischemia. The prolonged ADs in response to repetitive stimulation were, however, reversed to short-lasting ADs (duration, 7.13 +/- 1.44 s; n = 4; P < 0.02) by the same procedure, leaving the response to single stimulation unaffected. These findings suggest that, during the reperfusion period, Ca2+ influx into the CA1 pyramidal cells can be greatly increased through N-methyl-D-aspartate (NMDA) receptor-coupled ion channels if appropriately timed multiple synaptic inputs bombard these cells. Such Ca2+ influx may contribute to delayed death of CA1 pyramidal cells after transient cerebral ischemia if synaptic activity is maintained at relatively high levels during the reperfusion period.

Effects of midazolam and flumazenil on carotid sinus baroreflex control of circulation in rabbits

We have studied the effects of midazolam and flumazenil on the carotid sinus baroreflex, by examining mean arterial pressure (MAP) and heart rate (HR) responses to partial or complete bilateral carotid occlusion (BCO) in 12 conscious rabbits after aortic denervation. In eight rabbits, the responses to complete BCO were evaluated before and after cumulative doses of midazolam 0.5 and 1.0 mg kg-1, and after flumazenil 0.3 mg kg-1 following administration of midazolam. Midazolam and flumazenil had no effect on MAP or HR before complete BCO and neither affected the MAP response to complete BCO. Midazolam 0.5 and 1.0 mg kg-1 decreased the HR response to 60% and 58% of control, respectively. Flumazenil restored the midazolam-induced depression of the HR response to the control level. In the other four rabbits, we examined the MAP and HR responses to partial BCO (carotid artery pressure reduced by 5, 10 and 20 mm Hg) before and after midazolam 0.5 mg kg-1 and after flumazenil 0.3 mg kg-1 following administration of midazolam. The response to partial occlusion showed the same tendency as the response to complete BCO. These results indicate that midazolam attenuated the HR response of the carotid sinus baroreflex, flumazenil restored this midazolam-induced depression and neither drug affected the MAP response.

[Detection of a 14;18 breakpoint cluster region in B-cell lymphomas by PCR methods]

Cytogenetic studies of B-cell lymphomas have shown a t(14;18) chromosomal translocation in the majority of cases. However, its detection is not always simple to achieve and a new approach is urgently required. Recently, molecular biological analysis has revealed rearrangements of IgH and/or bcl-2 genes in the DNA of lymphomas. In these cases, a translocation-specific fragment, MBR (bcl-2/JH), could be amplified by PCR. Our present study clearly demonstrated the presence of MBR PCR products in 7 out of 8 cases with B-cell lymphoma. Thus, the results indicate that amplification of MBR by PCR is useful for detection of a translocation and therefore clinical diagnosis of lymphoma cells.

Homogeneous fluorescence detection method for human leukocyte antigen-DR typing following polymerase chain reaction amplification with sequence-specific primer

A fluorescent homogeneous method for the detection of sequence-specific amplification of human leukocyte antigen (HLA) alleles has been developed. In this approach, polymerase chain reaction sequence-specific primers (PCR-SSP) are used to amplify DRB1, DRB3, and DRB4 alleles. Lambda exonuclease and Exonuclease I are added to reduce background by digesting template DNA, partial primer dimer, and primer. PCR amplicons are then detected following the addition of a fluorescent dye (thiazole yellow dimer) which binds to double-stranded DNA. No transfer or wash steps are required. Thus, the risk of sample contamination, which is a major source of inaccuracy for DNA amplification methods, is greatly reduced. This approach is also faster and more easily automated than the standard approach using gel electrophoresis and ethidium bromide staining. Speed and automation are important considerations for HLA typing since the number of possible alleles for each HLA type is substantial. A homogeneous HLA-SSP typing method may be especially useful for clinical labs doing large numbers of samples and for the eventual automation of HLA DNA typing.

Effects of neural blockade and general anesthesia on the laser-Doppler skin blood flow waves recorded from the finger or toe

Effects of neural blockade and general anesthesia on the basic wave (BW) and the reflex wave (RW) among the laser-Doppler (L-D) skin blood flow waves recorded on the finger or toe were studied in 2 volunteers and 42 patients. The BW was continuous, rhythmic and independent of respiratory movements. The RW, which was induced by a deep inspiration or a snapping sound, was a transient marked reduction in blood flow. The BW was almost flattened and the RW was no longer induced at the finger under complete wrist block (n = 2), or under cervical or upper thoracic epidural anesthesia extended caudally over T7 (n = 2). On the other hand, the BW was still detected with reducing frequency and the RW could be provoked with one exception at the finger on the side with a sympathetic ganglion block at the C6 vertebral level (n = 14). The BW and RW at the toe were retained under lumbar subdural anesthesia (n = 6) as well. However, under the combination of lumbar subdural anesthesia and lower thoracic epidural anesthesia extending rostrally over T4 (n = 6), both the BW and the RW disappeared at the toe. In the course of deepening nitrous oxide/enflurane anesthesia (n = 10), the BW gradually reduced in frequency until it was almost flattened, and it became difficult to provoke the RW. L-D flowmetry of the finger or toe could be a useful clinical measure for detecting the presence or absence of sympathetic function controlling cutaneous vasomotion.

Effects of systemic cooling and rewarming on the evoked spinal cord potentials and local spinal cord blood flow in dogs

Changes in evoked spinal cord potential (ESCP) and in local spinal cord blood flow (local SCBF) were measured simultaneously in eight dogs in the course of systemic cooling and rewarming using a water mattress. PaCO2 was maintained at 35-40 mm Hg (temperature-uncorrected values) by adjusting ventilatory volume every 1 degree C change of esophageal temperature under N2O (60%)-O2-isoflurane (1.15%) anesthesia. Local SCBF and arterial blood pressure decreased and ESCP latencies increased linearly with the decrease in body temperature to 23-24 degrees C. The conductive ESCPs (non-synaptic components) showed temporary augmentation in amplitude before eventual decrease under cooling. These showed a tendency to return to the precooling baselines after the initiation of rewarming. These results demonstrate that conductive ESCPs could be available for intraoperative monitoring of spinal function under hypothermia down to 23-24 degrees C.

Control of systemic hypertension with diltiazem, a calcium-antagonist, in patients with a mildly elevated intracranial pressure: a comparative study

A cerebral vasodilatory action could represent a critical adverse effect of any drug used to control the systemic blood pressure (SBP) in patients with an elevated intracranial pressure (ICP), since such an action increases the ICP and thereby reduces the cerebral perfusion pressure (CPP). While several new calcium antagonists are now available, each drug exerts variable dilatory actions on the cerebral, coronary and peripheral vasculatures. Among these agents, diltiazem has been found to be sufficiently potent to control systemic hypertension but to have a less potent dilatory action on the cerebral vasculature in experimental animals. Based on such a characteristic, diltiazem appears to be an ideal drug for controlling systemic hypertension in patients with an elevated ICP. However, little has yet been investigated in the clinical setting. In the present study, the effects of three drugs, i.e., nitroglycerin, nicardipine and diltiazem, on the ICP were analysed retrospectively. Data were collected from patients who had demonstrated a mildly elevated ICP (mean ICP, 10-23 mmHg) and moderate systemic hypertension (mean SBP, 97-125 mmHg) during the period of 72 hours after surgical evacuation of spontaneous intracerebral haematomas. We reviewed the computer-based records of 385 patients, and identified 35 episodes in which the mean SBP was reduced by more than 10 mmHg by one of these three drugs alone during the initial 24 hours after haematoma evacuation.(ABSTRACT TRUNCATED AT 250 WORDS)