PR-39 and PR-11 peptides inhibit ischemia-reperfusion injury by blocking proteasome-mediated I kappa B alpha degradation

PR-39 inhibits proteasome-mediated I kappa B alpha degradation and might protect against ischemia-reperfusion injury. We studied PR-39, its truncated form PR-11, and a mutant PR-11AAA, which lacks the ability to prevent I kappa B alpha degradation, in a rat heart ischemia-reperfusion model. After 30 min of ischemia and 24 h of reperfusion, cardiac function, infarct size, neutrophil infiltration, and myeloperoxidase activity were measured. Intramyocardial injection of 10 nmol/kg PR-39 or PR-11 at the time of reperfusion reduced infarct size by 65% and 57%, respectively, which improved blood pressure, left ventricular systolic pressure, and relaxation and contractility (+/-dP/dt) compared with vehicle controls 24 h later. Neutrophil infiltration, myeloperoxidase activity, and the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule 1 were reduced. Thus PR-39 and PR-11 effectively inhibit myocardial ischemia-reperfusion injury in the rat in vivo. This effect is mediated by inhibition of I kappa B alpha degradation and subsequent inhibition of nuclear factor-kappa B-dependent adhesion molecules. The active sequence is located in the first 11 amino acids, suggesting a potential for oligopeptide therapy as an adjunct to revascularization.

Norepinephrine transporter mRNA expression after coitus in the rabbit brainstem

In the female rabbit, coitus induces a massive release of hypothalamic gonadotropin-releasing hormone (GnRH) within 20 min. The GnRH surge is preceded by an increase in hypothalamic norepinephrine (NE) release. Presumably, coitus stimulates NE, hence GnRH, release by increasing the activity of tyrosine hydroxylase (TH, the rate-limiting enzyme for NE synthesis) and/or decreasing the activity of norepinephrine transporter (NET, the key protein for NE re-uptake). Since NE cell bodies are located primarily in the brainstem, we hypothesize that coital signals are relayed to hypothalamic GnRH-secreting neurons via brainstem NE-containing perikarya. In support of this hypothesis, we found that both c-fos and TH mRNA expressions in brainstem noradrenergic areas, particularly in the A1 and A2 cell groups, increased within 30 min and returned to precoital levels within 60 min after coitus. Here we analyzed coitally induced changes in NET mRNA expression at 0, 15, 30 and 60 min postcoitus in the brainstem by in situ hybridization, using 35S-labeled rabbit NET RNA probes. In comparison with nonmated females (i.e., at 0 min), the expression of NET mRNA significantly increased (P<0.05) within 15 min postcoitus in the A1, but not the A2 area. By 30 min postcoitus, NET gene expression increased in the caudal portion of the A1 and in the caudal and central portion of the A2. By 60 min postcoitus, NET mRNA expression in the caudal and rostral portion of the A1 and the caudal and central portion of the A2 was still higher than NET mRNA expression in nonmated rabbits (P<0.05). No change in NET mRNA expression was observed in the A6. The results suggest that coitus increases NET mRNA expression in A1 and A2 noradrenergic areas within 15-30 min, and this enhanced NET mRNA expression was maintained for at least 60 min, particularly in the A2. These findings, in combination with our previous observation on increased TH gene expression within 30 min, but not 60 min, after coitus, further suggest that the coitus-induced NET transcriptional events within brainstem NE neurons may play an important role in the maintenance, and particularly in the termination, of hypothalamic NE release, hence regulating the size and duration of the coitus-induced GnRH surge.

[The electric pulse caused pore in the skin observed by fluorescence microscopy]

The objective of this study was to enunciate the difference in skin morphological changes between iontophroresis and electroporation for transdermal drug delivery (TDD). Fluorescence microscope was employed to observe the skin structure of human and snake in passive diffusion (control); iontophoresis was performed using direct current(0.5 mA/cm2) and electroporation was performed using intensive 380 V, pulse rate 4 ppm, pulse duration 5.5 ms, pulse number 100 and electric capacity 22 microF. Fluorescein was FITC. The results showed that for human skin in the passive, these were a few highlight fluorescent blots with scale of 15-30 microns and rough edge, but the edge of the blots became smooth and the scale did not change in the iontophoresis; when the scale of the blots was extended to 80-90 microns, the edge was smooth. For the snakes shin, the highlight blots were not sighted in the passive and iontophoresis, but they were found to be 25-30 microns in the electroporation. These data demonstrate that electric pulse can cause pore in the skin, thus creating a new route for drug permeation through skin.

Intramyocardial delivery of FGF2 in combination with radio frequency transmyocardial revascularization

Therapeutic angiogenesis and percutaneous transmyocardial revascularization (PMR) are potentially synergistic modalities to improve myocardial perfusion. To evaluate the efficiency of FGF2 delivery into an area that has been radio frequency (RF) ablated, we studied two catheter-based delivery methods, a direct injection system (Stiletto) and a combined RF ablation-delivery system (RF-PMR). Four groups (n = 3/group) of pigs received six transendocardial injections of (125)I-FGF2/fluorescent microspheres with either the Stiletto or the RF-PMR catheter. RF-PMR injections were preceded by a 0.6 sec RF ablation step. After either 1 or 24 hr, hearts and other tissues were harvested. Intramyocardial deposition sites were located with UV light and isolated. Specific activity per site was expressed as a percentage of total activity injected per site corrected for quenching. Injection site recovery was high for both catheter systems (average = 88%) and systemic uptake was low (< 6% in the liver). FGF2 retention was significantly higher with the Stiletto than the RF-PMR catheter (Stiletto 1 hr 41% +/- 17%, 24 hr 26% +/- 10%, RF-PMR 1 hr 21% +/- 14%, 24 hr 13% +/- 8%; P < 0.001), principally explained by the differences in catheter design. The Stiletto has a retractable needle and is optimized for intramyocardial delivery, whereas infusion from the RF-PMR device occurs at the endocardial surface and relies on channels created during RF ablation. Overall, FGF2 retention after transendocardial intramyocardial delivery by the Stiletto or the RF-PMR system is significantly higher than previously observed for intracoronary, intravenous and intrapericardial delivery. In conclusion, the combination of RF ablation and growth factor delivery using the RF-PMR system is feasible and efficient. Cathet Cardiovasc Intervent 2001;53:429-434.

Genomic structure and promoter characterization of an imprinted tumor suppressor gene ARHI

We have recently identified a maternally imprinted tumor suppressor gene, ARHI (aplysia ras homolog I), the expression of which is lost in ovarian and breast cancers. We have now characterized the genomic structure of the gene including its promoter and the methylation status of its upstream CpG islands. The ARHI gene spans approximately 8 kb containing two exons and one intron. Exon 1 contains 81 non-translated nucleotides, connected to exon 2 with a 3.2-kb intron. The entire protein-coding region is located within exon 2 and encodes a 229-residue small GTP-binding protein belonging to the Ras superfamily. Genomic structure analysis has identified three potential CpG islands. Two of them (CpG island I and II) are located within the promoter and adjacent exon 1 of the ARHI gene. Aberrant methylation of these CpG islands has been detected in breast cancer cells but not in normal epithelial cells, supporting the possibility that appropriate methylation status of the CpG islands in the promoter region may play a role in the downregulation of ARHI gene expression. A TATA box is found 27 bp upstream of the transcription start site associated with several putative transcription factor binding sites. Transient transfection with nested deletion constructs of the 2-kb ARHI promoter regions fused to a luciferase reporter indicated a 121-bp sequence upstream of the transcription initiation site is required for basal promoter activity. Interestingly, this is the region where lower promoter activity has been observed in cancer cells than in normal cells.

Quantitative determination of olanzapine in rat brain tissue by high-performance liquid chromatography with electrochemical detection

A sensitive assay was developed for the measurement of olanzapine in rat brain tissue using HPLC with electrochemical detection. The assay has a lower limit of quantitation of 0.5 ng/ml in tissue homogenate and utilizes a liquid-liquid extraction followed by reversed-phase HPLC for the quantitative analysis of olanzapine. The method provided a linear response for olanzapine over a concentration range of 0.5-100 ng/ml with a coefficient of determination (r2) greater than 0.9995. The extraction efficiencies of olanzapine and internal standard (LY170158) were greater than 82% in brain tissue. The intra-assay and inter-assay relative errors ranged from -5.38 to 17.60% and -3.25 to 10.53%, respectively. The intra-assay and inter-assay RSD values were in the range of 1.12 to 6.96% and 3.78 to 6.68%. Long-term stability studies showed that brain tissue homogenate samples spiked with olanzapine and internal standard are stable at -70 degrees C for at least 110 days. However, a room temperature stability study showed that olanazapine was not stable in brain homogenate if the sample was exposed at 25 degrees C longer than 2 h. This method has been used for the study of the disposition and pharmacokinetics of olanzapine in male Sprague-Dawley rats.

Inhibitory effects of ML-9, wortmannin, and Y-27632 on the chemotaxis of vascular smooth muscle cells in response to platelet-derived growth factor-BB

The chemotactic migration toward platelet-derived growth factor-BB of SM3, a cell line established from rabbit aorta smooth muscle, was examined by the Boyden chamber method. Myosin light-chain (MLC) kinase inhibitors ML-9 and wortmannin, and the Rho kinase inhibitor Y-27632 effectively reduced the migration. However, neither membrane ruffling nor the phosphorylation of MLC was inhibited concomitantly. The reduction is discussed with reference to a novel property of MLC kinase, which stimulates myosin ATPase activity without phosphorylating MLC [Ye et al. (1999) Proc. Natl. Acad. Sci. USA 96, 6666-6671].

Synergistic effects of olanzapine and other antipsychotic agents in combination with fluoxetine on norepinephrine and dopamine release in rat prefrontal cortex

To understand the mechanism of the clinical efficacy of olanzapine and fluoxetine combination therapy for treatment-resistant depression (TRD), we studied the effects of olanzapine and other antipsychotics in combination with the selective serotonin uptake inhibitors fluoxetine or sertraline on neurotransmitter release in rat prefrontal cortex (PFC) using microdialysis. The combination of olanzapine and fluoxetine produced robust, sustained increases of extracellular levels of dopamine ([DA](ex)) and norepinephrine ([NE](ex)) up to 361 +/- 28% and 272 +/- 16% of the baseline, respectively, which were significantly greater than either drug alone. This combination produced a slightly smaller increase of serotonin ([5-HT](ex)) than fluoxetine alone. The combination of clozapine or risperidone with fluoxetine produced less robust and persistent increases of [DA](ex) and [NE](ex). The combination of haloperidol or MDL 100907 with fluoxetine did not increase the monoamines more than fluoxetine alone. Olanzapine plus sertraline combination increased only [DA](ex). Therefore, the large, sustained increase of [DA](ex), [NE](ex), and [5-HT](ex) in PFC after olanzapine-fluoxetine treatment was unique and may contribute to the profound antidepressive effect of the olanzapine and fluoxetine therapy in TRD.

Oestrogen upregulates noradrenaline release in the mediobasal hypothalamus and tyrosine hydroxylase gene expression in the brainstem of ovariectomized rhesus macaques

Noradrenaline plays a key role in the initiation of ovulation in nonprimate species. A similar noradrenaline role in the primate has not been established experimentally. We utilized the ovariectomized-oestrogen-supplemented (OVX + E) rhesus macaque to examine the effects of intravenous (i.v.) infusion of oestradiol-17beta (E2) on the activity of the brain noradrenaline system. Experiment 1 established the induction of a preovulatory surge-like release of luteinizing hormone in OVX + E monkeys by i.v. infusion of E2 (OVX + E + E2). In experiment 2, a marked increase in hypothalamic microdialysate noradrenaline concentrations occurred after identical E2 infusion into the OVX + E monkeys that were used in experiment 1. In experiment 3, tyrosine hydroxylase (TH) mRNA expression in the locus coeruleus of the brainstem increased at various times after E2 infusion as determined by semiquantitative in situ hybridization. The amount of TH mRNA in OVX + E + E2 animals was higher (P < 0.05) than that in either the OVX + E or OVX monkeys; no difference was found in the latter two groups. Moreover, selected locus coeruleus sections from E2-infused monkeys were examined for the localization of oestrogen receptors (ER) by in situ hybridization. Both ER-alpha and ER-beta mRNAs were expressed in the locus coeruleus, although the expression was greater for ER-alpha than for ER-beta. We conclude that i.v. infusion of E2, which induces a preovulatory surge-like release of LH, stimulates brain noradrenaline activity; this enhanced activity likely involves an ER-mediated process and is reflected by hypothalamic noradrenaline release and locus coeruleus TH mRNA expression. The results support the concept that noradrenaline can influence the E2-stimulated ovulation in nonhuman primates and that the brainstem is one of the components in this neuroendocrine process.

Threonine phosphorylation diverts internalized epidermal growth factor receptors from a degradative pathway to the recycling endosome

Transregulation of the epidermal growth factor receptor (EGFR) by protein kinase C (PKC) serves as a model for heterologous desensitization of receptor tyrosine kinases, but the underlying mechanism remained unknown. By using c-Cbl-induced ubiquitination of EGFR as a marker for transfer from early to late endosomes, we provide evidence that PKC can inhibit this process. In parallel, receptor down-regulation and degradation are significantly reduced. The inhibitory effects of PKC are mediated by a single threonine residue (threonine 654) of EGFR, which serves as a major PKC phosphorylation site. Biochemical and morphological analyses indicate that threonine-phosphorylated EGFR molecules undergo normal internalization, but instead of sorting to lysosomal degradation, they recycle back to the cell surface. In conclusion, by sorting EGFR to the recycling endosome, heterologous desensitization restrains ligand-induced down-regulation of EGFR.

Enhanced transdermal delivery of tetracaine by electroporation

The effect of electroporation on the transport of tetracaine through skin in vitro was studied using side-by-side compartment diffusion cells method. After achieving steady state by passive diffusion, fluxes of tetracaine achieved with passive diffusion, electroporative pulse and iontophoresis were compared. Electroporation (square-wave pulse, voltage 130 V, pulse time 0.4 s, pulse frequency 40 pulses min(-1)) or iontophoresis (0.2.mA cm(-2), lasting for 4 h) increased the transport of tetracaine through skin. The flux of tetracaine at 0.25 h after electroporation (pulse number 400) was 54.6+/-6.0 microg.cm(-2).h(-1), that after iontophoresis was 17.4+/-5.8 microg.cm(-2).h(-1) and that after passive diffusion was 8.2+/-0.5 microg.cm(-2).h(-1). In addition, the fluxes of tetracaine increased with the increasing of pulse number. From these results, it is clear that electroporation is effective in enhancing transdermal delivery of tetracaine and its function is better than iontophoresis.

Molecular activation of noradrenergic neurons in the rabbit brainstem after coitus

Our previous studies indicate that coitus in female rabbits induces a gonadotropin-releasing hormone (GnRH) surge that is preceded by an increase in hypothalamic norepinephrine (NE) release. The additional findings of an enhanced tyrosine hydroxylase (TH) mRNA expression in the female brainstem after coitus, in addition to the appropriate topographic distribution of TH and dopamine-beta-hydroxylase (DBH), lead us to hypothesize that coital signals are relayed to hypothalamic GnRH-secreting neurons via brainstem NE-containing perikarya. Here we analyzed coitally activated areas in the brainstem by in situ hybridization of the oncogene c-fos, as well as the expression of TH mRNA at 0, 30 and 60 min postcoitus using specific 35S-labeled probes for c-fos and TH. To establish the identity of activated brainstem neurons, we immunocytochemically double-labeled cells with specific antibodies against Fos protein and DBH at 90 min postcoitus. Both c-fos and TH mRNAs were present at 0 min (control) in the A1, A2 and A6 brainstem-noradrenergic areas. At 30 min after coitus the expression of both genes significantly increased (P<0.01) in the A1 and A2 areas. By 60 min postcoitus the expression of c-fos mRNA decreased to control levels, while that of TH mRNA remained stimulated. Double-labeling of Fos and DBH indicated that the number of dual-labeled neurons increased (P<0.05) over control levels only in the A1 and A2 areas (not in A6) at 90 min postcoitus. These findings support the hypothesis that coitus activates transcriptional/translational events within brainstem NE neurons that culminate in the release of hypothalamic NE and hence a GnRH surge.

Chronic methylphenidate treatment enhances water maze performance following traumatic brain injury in rats

Methylphenidate (MPH), a central nervous system stimulant with dopaminergic activity, facilitates neurobehavioral outcome following cortical suction ablation injury, but its potential efficacy following experimental traumatic brain injury (TBI) is unknown. Thus, beginning 24 h after controlled cortical impact injury or sham surgery, male Sprague-Dawley rats were injected (i.p.) once daily for 18 days with either MPH (5 mg/kg) or saline vehicle (VEH) and motor function assessed on post-operative days 1-4, followed by Morris water maze training to find a hidden platform on days 14-18. The MPH treatment regimen was ineffective in accelerating beam-balance or beam-walk recovery, but did significantly decrease swim latencies when compared to VEH-treated controls. The results are consistent with published studies showing improved outcome with MPH therapy. Furthermore, this positive finding with delayed treatment suggests that strategies that enhance catecholamine neurotransmission during the chronic post injury phase may be a useful adjunct in ameliorating some of the neurobehavioral sequelae following TBI in humans.

Regulation of neurogenesis by interactions between HEN1 and neuronal LMO proteins

Basic-helix-loop-helix transcription factors regulate neurogenesis and neuronal differentiation by as yet unknown mechanisms. We show that an embryonic neuronal-specific basic-helix-loop-helix protein, HEN1 (also known as NSCL1 or NHLH), interacts with ‘LIM only’ proteins. Examination of the expression patterns of XHEN1 and XLMO-3, the Xenopus homologues of these human genes, reveals extensive overlap during early neurogenesis: at the onset of gastrulation on the dorsal side of the blastopore lip and, subsequently, in the prospective neural plate. Binding of XLMO-3 increases the transcriptional activity of XHEN1 in vivo. Co-expression of these two genes in Xenopus embryos induces a cascade of expression of neuronal-specific basic-helix-loop-helix proteins that leads to neuronal differentiation. We propose that XHEN1, in concert with XLMO-3, is a critical regulator of neurogenesis.

Stable transfectants of smooth muscle cell line lacking the expression of myosin light chain kinase and their characterization with respect to the actomyosin system

We constructed a plasmid vector having a 1.4-kilobase pair insert of myosin light chain kinase (MLCK) cDNA in an antisense direction to express antisense mRNA. The construct was then transfected to SM3, a cell line from vascular smooth muscle cells, producing a few stable transfectants. The down-regulation of MLCK expression in the transfectants was confirmed by both Northern and Western blots. The control SM3 showed chemotaxic motility to platelet-derived growth factor-BB, which was supported by lamellipodia. However, the transfectants showed neither chemotaxic motility nor developed lamellipodia, indicating the essential role of MLCK in the motility. The specificity for the targeting was assessed by a few tests including the rescue experiment. Despite this importance of MLCK, platelet-derived growth factor-BB failed to induce MLC20 phosphorylation in not only the transfectants but also in SM3. The mode in which MLCK was involved in the development of membrane ruffling is discussed with special reference to the novel property of MLCK that stimulates the ATPase activity of smooth muscle myosin without phosphorylating its light chain (Ye, L.-H., Kishi, H., Nakamura, A., Okagaki, T., Tanaka, T., Oiwa, K., and Kohama, K. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 6666-6671).

[Study on the antitumor activity of CBMC activated by IL-12 alone or in combination with IL-2]

OBJECTIVE

To investigate the efficacy of cord blood mononuclear cells (CBMC) activated by interleukin-12 (IL-12) alone or in combination with interleukin-2 (IL-2) in tumor cells.

METHODS

The cytotoxicity of CBMC and peripheral blood mononuclear cells (PBMC) activated by IL-12 and/or IL-2 was measured with (3)H-TdR release assay, and the morphological change of K562 cells incubated with activated CBMC was observed.

RESULTS

(1) CBMC activated by 10 IU/ml IL-12 produced significant cytotoxic activities which were (27.23 +/- 4.92)% and (29.12 +/- 3.46)% against K562 and Raji cells, respectively; moreover, 10 IU/ml IL-12 could be synergized with the same dose of IL-2 in enhancing the cytotoxicities which were (47.60 +/- 4.60)% and (38.69 +/- 4.86)% against the two target cells, respectively. (2) Short-term incubation with IL-12 activated CBMC increased the cytotoxicity to K562 cells, and long-term incubation increased the cytotoxicity to Raji cells. (3) No NK lytic activity of CBMC could be detected before cytokines stimulation. After stimulated by 10 IU/ml IL-12, NK lytic activity of CBMC was similar to that of PBMC. (4) K562 cells demonstrated obvious apoptosis after cultured with activated CBMC.

CONCLUSION

CBMC activated by IL-12 had evident antitumor activity, which was further increased when IL-12 in combination with IL-2. These results showed the potential value to improve the graft-versus-leukemia (GVL) response after cord blood progenitor cell transplantation.

Correolide and derivatives are novel immunosuppressants blocking the lymphocyte Kv1.3 potassium channels

The voltage-gated potassium channel, Kv1.3, is specifically expressed on human lymphocytes, where it controls membrane potential and calcium influx. Blockade of Kv1.3 channels by margatoxin was previously shown to prevent T cell activation and attenuate immune responses in vivo. In the present study, a triterpene natural product, correolide, was found to block Kv1.3 channels in human and miniswine T cells by electrophysiological characterization. T cell activation events, such as anti-CD3-induced calcium elevation, IL-2 production, and proliferation were inhibited by correolide in a dose-dependent manner. More potent analogs were evaluated for pharmacokinetic profiles and subsequently tested in a delayed-type hypersensitivity (DTH) response to tuberculin in the miniswine. Two compounds were dosed orally, iv, or im, and both compounds suppressed DTH responses, demonstrating that small molecule blockers of Kv1.3 channels can act as immunosuppressive agents in vivo. These studies establish correolide and its derivatives as novel immunosuppressants.

[Clinical study of gentamycin-loaded chitosan drug delivery system]

An clinical and pharmacokinetic study for a drug delivery system (DDS) of gentamycin-loaded chitosan bar were carried out with the purpose to evaluate its efficacy and giving further data for its clinical applications. Eighteen cases of chronic osteomyelitis were treated by surgical necrectomy with implantation of gentamycin-load chitosan bar in the prepared bone cavity. After operation, the concentration of gentamycin in serum and wound drainage fluid were examined at different times and blood urea nitrogen (BUN) and serum creatinine (Cr) as well. The clinical results were evaluated by the conditions of wound healing and clinical and roentgenographic manifestations. The results showed that the serum gentamycin concentration reached its peak level (0.86 microgram/ml) at 24 hours after operation and lasted for 4 days. No increase in the concentrations of BUN and Cr were observed after implantation. The gentamycin concentration in wound drainage fluid was several hundred times higher than the minimum inhibitory concentration (MIC) for staphylococcus aureus. All of the 18 cases were followed up for 24.8 months (in an range of 6-34 months) 16 patients received initial cure and without any recurrence. So, it could be concluded that the gentamycin-loaded chitosan DDS was a simple and effective method for the treatment of chronic osteomylitis without the necessity to carry out a second operation to remove the drug carrier, and it was sound to popularize its clinical application.

Differences in Ca2+ channels governing generation of miniature and evoked excitatory synaptic currents in spinal laminae I and II

Many neurons of spinal laminae I and II, a region concerned with pain and other somatosensory mechanisms, display frequent miniature "spontaneous" EPSCs (mEPSCs). In a number of instances, mEPSCs occur often enough to influence neuronal excitability. To compare generation of mEPSCs to EPSCs evoked by dorsal root stimulation (DR-EPSCs), various agents affecting neuronal activity and Ca2+ channels were applied to in vitro slice preparations of rodent spinal cord during tight-seal, whole-cell, voltage-clamp recordings from laminae I and II neurons. The AMPA/kainate glutamate receptor antagonist CNQX (10-20 microM) regularly abolished DR-EPSCs. In many neurons CNQX also eliminated mEPSCs; however, in a number of cases a proportion of the mEPSCs were resistant to CNQX suggesting that in these instances different mediators or receptors were also involved. Cd2+ (10-50 microM) blocked evoked EPSCs without suppressing mEPSC occurrence. In contrast, Ni2+ ( Collapse

Key Words

• mepscs
• epscs
• lva ca²⁺ channels
• spinal laminae i and ii
• spinal dorsal horn
• rodent
• mibefradil
• la³⁺

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MESH Headings

• 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology
• Animals
• Cadmium/pharmacology
• Calcium Channel Blockers/pharmacology
• Calcium Channels/metabolism
• Cricetinae
• Excitatory Amino Acid Antagonists/pharmacology
• Excitatory Postsynaptic Potentials/drug effects
• Ganglia, Spinal/metabolism
• In Vitro Techniques
• Nickel/pharmacology
• Patch-Clamp Techniques
• Potassium/pharmacology
• Potassium/physiology
• Rats
• Rats, Sprague-Dawley
• Tetrodotoxin/pharmacology

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Grants

• F32 NS010321 NINDS NIH HHS
• R01 NS010321 NINDS NIH HHS
• NS10321 NINDS NIH HHS

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Pathogenic poxviruses reveal viral strategies to exploit the ErbB signaling network

Virulence of poxviruses, the causative agents of smallpox, depends on virus-encoded growth factors related to the mammalian epidermal growth factor (EGF). Here we report that the growth factors of Shope fibroma virus, Myxoma virus and vaccinia virus (SFGF, MGF and VGF) display unique patterns of specificity to ErbB receptor tyrosine kinases; whereas SFGF is a broad-specificity ligand, VGF binds primarily to ErbB-1 homodimers, and the exclusive receptor for MGF is a heterodimer comprised of ErbB-2 and ErbB-3. In spite of 10- to 1000-fold lower binding affinity to their respective receptors, the viral ligands are mitogenically equivalent or even more potent than their mammalian counterparts. This remarkable enhancement of cell growth is due to attenuation of receptor degradation and ubiquitination, which leads to sustained signal transduction. Our results imply that signal potentiation and precise targeting to specific receptor combinations contribute to cell transformation at sites of poxvirus infection, and they underscore the importance of the often ignored low-affinity ligand-receptor interactions.

Sulfhydryl-dependent biotransformation and macromolecular binding of 1,2-dibromo-2,4-dicyanobutane in blood

1,2-Dibromo-2,4-dicyanobutane (BCB) is a broad-spectrum microbicide used commercially in consumer products. The objectives of this study were to elucidate the biotransformation of BCB, characterize its ability to covalently bind macromolecules, and predict the possible toxicological ramifications of such events. After iv administration of [14C]BCB to male Fischer 344 rats, 14C-equivalents were observed to bind gradually to blood constituents. By 48 hr, approximately 12% of the total dose was covalently bound. At no time was parent compound detected in the blood. However, the debrominated BCB metabolite 2-methyleneglutaronitrile (MGN) was observed. In vitro experiments revealed that BCB was extremely labile and was readily debrominated in fresh whole blood, erythrocyte preparations, and buffered glutathione (GSH) solutions. In each case, the formation of MGN was inhibited by the alkylation of free sulfhydryls with N-ethylmaleimide (NEM). For every 1 mol of BCB converted to MGN, 2 mol of GSH were oxidized to glutathione disulfide (GSSG) (BCB + 2 GSH --> MGN + GSSG + 2 HBr). The oxidation of free sulfhydryls during the conversion of BCB to MGN caused erythrocyte hemolysis (EC50 approximately 1 mM) in isolated preparations. Hemolysis was increased by coincubation of BCB with NEM (EC50 approximately 0.3 mM) and was decreased by coincubation with GSH (EC50 > 3 mM). However, MGN did not cause hemolysis of erythrocytes, even at concentrations 10-fold higher than the EC50 of BCB. In vitro experiments also demonstrated that incubation with either BCB or MGN resulted in significant macromolecular binding to the erythrocyte fraction of the blood (approximately 80%). Incubation with NEM resulted in a significant decrease in binding for both BCB (11.3% bound) and MGN (29.5% bound). Because BCB is rapidly debrominated in whole blood, it appears that MGN is the reactive species responsible for macromolecular binding. From these studies, we conclude that the conversion of BCB to MGN is mediated by a free sulfhydryl-dependent biotransformation pathway. Furthermore, BCB biotransformation is required for erythrocyte binding, and the consumption of free sulfhydryls associated with the biotransformation of BCB is responsible for hemolysis.

TCM differential treatment of child hood persisting pneumonia--a report of 52 cases

According to TCM differentiation of the symptoms and signs, 52 children with presisting pneumonia were divided into the following four types: 1) deficiency of body fluid due to accumulation of heat in the lung, 2) earth failing to generate metal, 3) deficiency of the Ying and Wei systems, and 4) excessiveness of pathogens due to qi deficiency. After treatment for 2-3 weeks, 40-cases were cured, 8 improved, and 4 ineffective.

[The effects of graded spinal cord injuries on transcranial electric stimulation motor evoked potentials in the rat]

OBJECTIVE

To study the effects of graded spinal cord injury (SCI) on the motor evoked potentials (MEP) characteristics and the prognostic value of MEP for the motor function.

METHOD

Modified Allen's method was used by weight drop force of 30 gcf, 50 gcf, 80 gcf and 100 gcf on the T(8 - 9) spinal cord of 40 SD rats in order to make SCI models. MEP was recorded continuously at L(1 - 2) epidurally and bilateral gastrocnemius muscles before and after the spinal cord lesion was produced (followed up for 1 month). The inclined plane and Tarlov technique were used to assess clinical neurological function.

RESULT

The amplitude of rat's MEP changed significantly with graded SCI, the more sever the lesion, the lower the potentials. mMEP was more sensitive than scMEP, though the abolishment of mMEP soon after SCI didn't indicate that the animals could not regain ambulation. Changes in amplitude of scMEP recorded early after SCI were collaborate significantly with inclined plane (gamma = 0.9665, P < 0.01) and Tarlov scale (gamma = 0.8893, P < 0.01) assessed 1 month later, and can be used as a chronic measure parameter of motor function prognosis. scMEP still existed 1 month after SCI in 3 of 11 rats (27.3%) without any voluntary movement in bilateral hindlimbs, suggesting that some parts of conductive function still existed in the spinal cord. So it should be called "discomplete SCI".

CONCLUSIONS

scMEP can be used as a reliable parameter for motor function prognosis, because it reflects objectively and sensitively the severity of central motor neurol fiber injury.

[Tail-suspended rats with inguinal canal ligation and their myocardial function]

To examine the effect of testosterone level on myocardial contractility and to prevent the testis from sliding into abdominal cavity when subjected to tail-suspension, a new tail-suspended model of rat with its inguinal canal ligated was made. Rats suspended for 4 w without inguinal canal ligation (SUS) exhibited significant reduction in weight of testis (CON 1.70 +/- 0.19 g; SUS 0.60 +/- 0.16 g) and in serum testosterone level (CON 99.5 +/- 32.7 ng/dl; SUS 23.0 +/- 13.2 ng/dl) (P<0.01). Unexpectedly, 4 w tail-suspension of rats with inguinal canal ligation (ST) also showed significant changes in testis weight (1.21 +/-0.30 g) and serum testosterone level (40.7 +/- 32.6 ng/dl). A significant decrease of the developed tension of the papillary muscle of the left cardiac ventricle was observed in SUS and ST group as compared with controls (CON: 3.93 +/- 0.42 g/mm2, SUS: 2.54 +/- 0.85 g/mm2, ST: 2.60 +/- 0.73 g/mm2). There was no relationship between the developed tension and serum testosterone level. It suggests that the decrease of blood supply of the testis may result in an atrophy of the testis in ST group.

Metabolic and dispositional fate of 1,2-dibromo-2,4-dicyanobutane in the male fischer 344 Rat

Studies were conducted to characterize the absorption, disposition, metabolism, and excretion of 1,2-dibromo-2,4-dicyanobutane (BCB; methyldibromoglutaronitrile) following iv, oral, and topical administration to male Fischer 344 rats. Following iv administration of [14C]BCB (8 mg/kg, 120 microCi/kg), no parent compound was detected in the blood; however, its debrominated metabolite, 2-methyleneglutaronitrile (2-MGN; Cmax 7.3 micrograms/ml), was observed up to 1 hr. Within 72 hr, greater than 60% of the dose was excreted in the urine and 4.1% in the feces, and 6.6% was exhaled as 14CO2. Although less than 5% of the dose was retained in tissues, approximately 12% was bound to the erythrocyte fraction of the blood. Following oral administration of [14C]BCB (80 mg/kg, 100 microgramsCi/kg), approximately 85% of the dose was absorbed, whereas 72% of the dosed radioactivity was recovered in the urine and 9.7% in the feces, 7.5% was exhaled as 14CO2, 3.5% bound to tissues, and 2. 6% bound to blood. Although parent compound could not be detected in the blood following oral administration, 2-MGN was detected (Cmax 0. 32 micrograms/ml). Following topical application of [14C]BCB (25 mg/kg, 50 microgramsCi/kg), less than 12% of the dose was absorbed, with the major route of excretion being the urine (6.6% of dose). Urinary metabolite profiles were nearly identical for each route of administration, and the primary urinary metabolite was a mercapturate conjugate of 2-MGN that was identified as N-acetyl-S-(2, 4-dicyanobutane)-L-cysteine. BCB was found to be extremely labile in whole blood, plasma, and glutathione containing solutions, and in each case the formation of 2-MGN could be reduced by the alkylation of free-sulfhydryls with N-ethylmaleimide. These results suggest that BCB is totally debrominated prior to systemic distribution, and tissue exposure to intact BCB seems to be exceedingly low regardless of route of administration.

[Endovascular exclusion of abdominal aortic aneurysm]

OBJECTIVE

To explore the indications, methods, manipulations, and problems of endovascular exclusion of abdominal aortic aneurysm (AAA).

METHOD

Under general anesthesia and dynamic supervision of DSA, an endovascular exclusion with a stent-graft complex of 11.0 cm x 2.6 cm was successfully performed on a 70-year-old man contraindicated for major open surgery with AAA of 10.0 cm x 6.0 cm and an AAA neck of 2.5 cm x 1.6 cm.

RESULT

The patient was up and about on the first postoperative day. Duplex scan (by the end of the first postoperative week) and CT (on the postoperative 20th day) revealed a completely excluded AAA by the stent-graft that was patent and had an inner diameter of 2.2-2.4 cm, without migration and torsion. The primary AAA sac was full of thrombi and no patent lumbar and inferior mesenteric arteries were observed. The external diameter of AAA was unchanged, renal and iliac arteries were all patent, but a micro-crevice between the proximal end of the stent-graft and the anterior wall of the AAA neck was revealed. Six months postoperative follow-up showed that the patient's abdominal pulsatile mass and the left lower extremity's claudication disappeared.

CONCLUSION

Endovascular exclusion of AAA is of great practical value.

Frequent coexpression of MRP/GS-X pump and gamma-glutamylcysteine synthetase mRNA in drug-resistant cells, untreated tumor cells, and normal mouse tissues

Expression of the multidrug-resistance protein gene MRP, which confers non-P-glycoprotein-mediated multidrug resistance, has been found in many drug-resistant variants and tumor samples. Recent studies have demonstrated that MRP functions as an ATP-dependent transporter functionally related to the previously described glutathione-conjugate (GS-X) pump. We have shown recently that the MRP and gamma-glutamylcysteine synthetase (gamma-GCS) heavy subunit mRNA levels are coordinately overexpressed in cisplatin (CP)-resistant human leukemia cells (Ishikawa et al., J Biol Chem 271: 14981-14988, 1996) and frequently co-elevated in human colorectal tumors (Kuo et al., Cancer Res 56: 3642-3644, 1996). In the present study, we showed the coexpression patterns of thirteen additional human drug-resistant cell lines representing different tumor cell origins selected with different agents, except for one doxorubicin-selected line which demonstrated minor elevation in MRP mRNA with no detectable increase in gamma-GCS mRNA, suggesting that the increase of MRP mRNA preceded the increase in gamma-GCS mRNA. Furthermore, in seventeen randomly selected untreated tumor cell lines, the overall correlation coefficient between MRP and gamma-GCS mRNA levels was 0.861. In normal mice, the correlation coefficient of mrp and gamma-gcs mRNA was 0.662 in fourteen tissues (kidney and liver were not included) analyzed. Kidney and liver expressed low levels of mrp relative to gamma-gcs; however, these two tissues expressed high levels of a functionally related mrp homologue, mrp2 (cMoat or cMrp), which may have compensated for the underexpressed mrp in maintaining the total GS-X pump activities. Altogether, these results demonstrated the frequent coexpression of these two genes in various cell settings.

Comparison of biodegradable and metallic tension-band fixation for patella fractures. 38 patients followed for 2 years

We compared the outcome of patella fractures fixed by biodegradable tension-band (B) with self-reinforced polyglycolide or self-reinforced poly-L-lactide plugs and polyester ligaments or by metallic tension-band (M) with Kirschner wires and metallic cerclage wire in a randomized study. 38 fractures (18 with B and 20 with M) were treated. The follow-up time was 24 (14-32) months. The fractures healed in all patients after a medium of 8 weeks. In the B group, the clinical outcome was good in 13, fair in 4, and poor in 1 patient. In the M group, the corresponding figures were 15, 3 and 2. There were no clinical or radiographic differences between the two methods. Patella fractures can be treated, successfully using biodegradable tension-band fixation with no need for a second operation to remove the implants after bone union.

Microelectrode arrays for stimulation of neural slice preparations

A planar 6 x 6 array of iridium electrodes with four reference electrodes has been developed for use with neural tissue preparations. Precise knowledge of the relative locations of the array elements allows for spatial neurophysiological analyses. The 10 microns diameter platinized iridium electrodes on a 100 microns pitch have been used to stimulate acutely prepared slices of spinal cord from free-ranging rodents. An intracellular recording from a single neuron in the substantia gelatinosa (SG) using the whole-cell, tight-seal technique allowed low noise, high resolution studies of excitatory or inhibitory electrical responses of a given neuron to inputs from the primary afferent fibers or from stimulation by individual electrodes of the array. The resulting maps of responses provide an indication of the interconnectivity of neural processes. The pattern emerging is that of limited interconnectivity in the SG from areas surrounding a recorded neuron but with strong excitatory or inhibitory effects from those oriented in a longitudinal (rostral-caudal) direction relative to the neuron. The observations to date suggest the neurons of the SG are arranged in sets of independent networks, possibly related to sensory modality and input from particular body regions.

Effect of age and gender on azimilide pharmacokinetics after a single oral dose of azimilide dihydrochloride

Azimilide is a new class III antiarrhythmic drug that blocks K+ channels. To determine the effects of age and gender on azimilide pharmacokinetics, a single 150-mg oral dose was administered to 66 healthy volunteers in a 3 x 2 factorial design (age groups of 18-40, 41-64, and > or = 65 years). Blood and urine were analyzed for azimilide and metabolites. The single dose was well-tolerated. Azimilide was 94% plasma protein-bound, and binding was not affected by age or gender. Age does not affect azimilide pharmacokinetics. The renal clearance of azimilide was significantly higher in women than in men (19%), but oral clearance did not differ between genders. Although the maximum azimilide concentration (Cmax) was 27% higher in women, time to maximum concentration or area under the azimilide concentration-time curve were not different from those for men. Body weight-adjusted Cmax did not differ between genders. Dosing adjustments based on either age or gender are not required.

Absorption, disposition, and metabolism of trans-methyl styryl ketone in female B6C3F1 mice

trans-Methyl styryl ketone (MSK; trans-4-phenyl-3-buten-2-one) is a beta-unsaturated ketone that has a wide range of uses in industry, as well as consumer products. MSK does not appear to be overtly toxic in animal models, however, it has been shown to be mutagenic in several in vitro assays after S-9 activation. In this study experiments were conducted to characterize MSK absorption, distribution, metabolism, and elimination after iv, oral, and topical administration to female B6C3F1 mice. After iv administration, [14C]MSK (20 mg/kg; 120 microCi/kg) was rapidly cleared from the blood as evidenced by the following pharmacokinetic values (mean +/- SD): terminal disposition half-life (t1/2), 7.98 +/- 1.72 min; mean residence time, 5.6 +/- 1.7 min; steady-state apparent volume of distribution (Vss), 3.33 +/- 0.75 liters/kg; and systemic body clearance (CLs), 0.53 +/- 0.05 liters/min/kg. Within 48 hr, 92.4% of the dose was excreted in the urine and 3.5% in the feces. The major blood metabolites after iv administration were identified by GC-MS as the 4-phenyl-3-buten-2-ol (methyl styryl carbinol), 4-hydroxy-4-phenyl-2-butanone, and benzyl alcohol. After oral administration of [14C]MSK (200 mg/kg; 100 microCi/kg), 95% of the dosed radioactivity was recovered in the urine and 1.2% in the feces within 48 hr. Major urinary metabolites were identified by LC-MS/MS as N-phenylacetyl-l-glycine (35.1% of dose) and N-benzyl-L-glycine (19.1% of dose). Only a small amount of MSK was detected in the blood after oral administration ( approximately 0.73 microg/ml at 10 min), and [14C]-equivalents in the blood never exceeded 2.8% of the dose. Ater topical application of [14C]MSK (250 mg/kg; 50 microCi/kg), approximately 40% of the dose was absorbed and 84.5% of the absorbed dose was excreted into the urine (36% of the total dose). Urinary metabolites were similar to those described for oral administration. Importantly, [14C]-equivalents were not detected in the blood at any time after dermal administration. These results indicate that the rate of MSK clearance is equivalent to its rate of absorption, and tissue exposure to intact MSK is expected to be limited.

Poly(ADP-ribose) polymerase gene disruption renders mice resistant to cerebral ischemia

Nitric oxide (NO) and peroxynitrite, formed from NO and superoxide anion, have been implicated as mediators of neuronal damage following focal ischemia, but their molecular targets have not been defined. One candidate pathway is DNA damage leading to activation of the nuclear enzyme, poly(ADP-ribose) polymerase (PARP), which catalyzes attachment of ADP ribose units from NAD to nuclear proteins following DNA damage. Excessive activation of PARP can deplete NAD and ATP, which is consumed in regeneration of NAD, leading to cell death by energy depletion. We show that genetic disruption of PARP provides profound protection against glutamate-NO-mediated ischemic insults in vitro and major decreases in infarct volume after reversible middle cerebral artery occlusion. These results provide compelling evidence for a primary involvement of PARP activation in neuronal damage following focal ischemia and suggest that therapies designed towards inhibiting PARP may provide benefit in the treatment of cerebrovascular disease.

[Laser assisted uvulopalptoplasty treatment for obstructive sleep apnea syndrome]

71 patients of obstructive sleep apnea symdrome (OSAS) were treated by Nd:YAG laser assisted uvulopalptoplasty (LAUP). According to the atonamic features of every patient, and type of operation which should be selected, the success rate of surgery would increase, and complications would be reduced. The effect rate is 97.2% by clinic, 90.0% by polysimnograph (PSG).

Simultaneous determination of cyclohexene oxide and its metabolites in rat plasma and urine by gas chromatography

An assay was developed for the simultaneous measurement of cyclohexene oxide and its metabolites (cyclohexanol, trans-cyclohexane-1,2-diol, cyclohexane-1,2-diol-O-glucuronide, and N-acetyl-S-(2-hydroxycyclohexyl)-L-cysteine) in rat urine and plasma using gas chromatography. A mixture of ethyl acetate-acetonitrile (70:30) was used as the extracting solvent for both matrices. This liquid-liquid extraction procedure was followed by the separation of cyclohexene oxide and its metabolites on an HP-FFAP fused-silica capillary column. In order to determine the amount of cyclohexane-1,2-diol-O-glucuronide, samples were incubated at 37 degrees C with beta-glucuronidase and the amount of cyclohexane-1,2-diol formed from the reaction determined. The extraction efficiencies of cyclohexene oxide and cyclohexanol were greater than 90% both in urine and plasma. However, recovery from the plasma and urine for trans-cyclohexane-1,2-diol (60-68%) and N-acetyl-S-(2-hydroxycyclohexyl)-L-cysteine (approximately 76%) were considerably less. Long term stability studies showed that urine samples spiked with cyclohexene oxide and trans-cyclohexane-1,2-diol are stable at -20 degrees C for up to 9 weeks. However, plasma samples are only stable for up to 2 weeks under the same conditions. The calibration curves for all analytes were linear over the range of 12.5 to 400 micrograms/ml and correlation coefficients (r2) were greater than 0.990. The limit of detection for cyclohexene oxide, cyclohexanol, and N-acetyl-S-(2-hydroxycyclohexyl)-L-cysteine is 1.56 micrograms/ml, while the limit of detection for trans-cyclohexane-1,2-diol is 3.12 micrograms/ml. This method has been used for the determination of the disposition and metabolism of cyclohexene oxide, and may be applied in environmental monitoring, as well as in microbiological studies for other epoxide materials.

Nerve growth factor attenuates cholinergic deficits following traumatic brain injury in rats

Traumatic brain injury (TBI) results in chronic derangements in central cholinergic neurotransmission that may contribute to posttraumatic memory deficits. Intraventricular cannula (IVC) nerve growth factor (NGF) infusion can reduce axotomy-induced spatial memory deficits and morphologic changes observed in medial septal cholinergic neurons immunostained for choline acetyltransferase (ChAT). We examined the efficacy of NGF to (1) ameliorate reduced posttraumatic spatial memory performance, (2) release of hippocampal acetylcholine (ACh), and (3) ChAT immunoreactivity in the rat medial septum. Rats (n = 36) were trained prior to TBI on the functional tasks and retested on Days 1-5 (motor) and on Day 7 (memory retention). Immediately following injury, an IVC and osmotic pump were implanted, and NGF or vehicle was infused for 7 days. While there were no differences in motor performance, the NGF-treated group had significantly better spatial memory retention (P < 0.05) than the vehicle-treated group. The IVC cannula was then removed on Day 7, and a microdialysis probe was placed into the dorsal hippocampus. After a 22-h equilibration period, samples were collected prior to and after administration of scopolamine (1 mg/kg), which evoked ACh release by blocking autoreceptors. The posttraumatic reduction in scopolamine-evoked ACh release was completely reversed with NGF. Injury produced a bilateral reduction in the number and cross-sectional area of ChAT immunopositive medial septal neurons that was reversed by NGF treatment. These data suggest that cognitive but not motor deficits following TBI are, in part, mediated by chronic deficits in cholinergic systems that can be modulated by neurotrophic factors such as NGF.

Oral and topical absorption, disposition kinetics, and the metabolic fate of trans-methyl styryl ketone in the male Fischer 344 rat

trans-Methyl styryl ketone (MSK; trans-4-phenyl-3-buten-2-one) is a beta-unsaturated ketone that has a wide range of uses in industry and is present in numerous consumer products. Although MSK has been shown to be positive in several in vitro mutagenic assays, it does not seem to be overtly toxic in animal models. This lack of toxicity may relate to its poor absorption and/or rapid elimination. However, little is known about the fate of MSK in the body. Studies were conducted to characterize the absorption, and disposition kinetics of MSK after intravenous, oral, and topical administration to male Fischer 344 rats. After intravenous administration of [14C]MSK (20 mg/kg, 120 microCi/kg), blood concentration-time data could be characterized with a biexponential equation and apparent first-order elimination kinetics. The following pharmacokinetic parameter values were obtained (mean +/- SD): terminal disposition half-life, 17.7 +/- 0.08 min; apparent steady-state volume of distribution, 0.89 +/- 0.14 liters/kg; systemic body clearance, 68.9 +/- 10.0 ml/kg *min; and mean residence time, 13.1 +/- 2.2 min. Within 48 hr, 95.5% of the dose was excreted in the urine and 2.7% in the feces. The major blood metabolite after intravenous administration was identified by GC/MS as the 4-phenyl-3-buten-2-ol (methyl styryl carbinol). After oral administration of [14C]MSK (200 mg/kg, 100 microCI/kg), approximately 96.6% of the dosed radioactivity was recovered in the urine and 4.8% in the faces within 48 hr. Major urinary metabolites identified by LC-MS/MS and quantified by HPLC radioassay were N-phenylacetyl-L-glycine (64.9% of dose) and N-benzyl-L-glycine (9.9% of dose). Parent compound could not be detected in the blood after oral administration, and 14C-equivalents in the blood never exceeded 1.3% of the dose. Results suggest near-total presystemic elimination of the oral dose. After topical application of [14C]MSK (250 mg/kg, 50 microCi/kg), > 60% of the dose was absorbed, and the majority of the dose was excreted into the urine (55% of dose) in the form of metabolites. Urinary metabolites were similar to those described after oral administration. 14C-equivalents were not detected in the blood at any time after topical administration. These results indicate that MSK is almost totally metabolized before systemic distribution after oral or topical administration. The systemic exposure dose of MSK seems to be exceedingly low at the doses studied herein.

Absorption, disposition kinetics, and metabolic pathways of cyclohexene oxide in the male Fischer 344 rat and female B6C3F1 mouse

Cyclohexene oxide (CHO) is a monomer intermediate used in the synthesis of pesticides, pharmaceuticals, and perfumes. Although CHO has a variety of industrial uses where direct human exposure is possible, very little is known about its fate in the body. Therefore, the objectives of this study were to determine the absorption, distribution, metabolism, and excretion of cyclohexene oxide after oral, intravenous, and dermal exposure in male Fischer 344 rats and female B6C3F, mice. After intravenous administration of [14C]CHO (50 mg/kg), CHO was rapidly distributed, metabolized, and excreted into the urine. Plasma concentrations of CHO rapidly declined and were below the limit of detection within 60 min. Average (+/- SD) values for terminal disposition half-life, apparent volume of distribution at steady-state, and systemic body clearance were: 19.3 +/- 1.6 min; 0.44 +/- 0.08 liter/kg; and 31.3 +/- 0.5 ml/kg * min, respectively. After oral administration of [14C]CHO (10 and 100 mg/kg), it was found that 14C-equivalents were rapidly excreted in the urine of both species. At 48 hr, the majority of the dose (73-93%) was recovered in urine, whereas fecal elimination accounted for only 2-5% of the dose. At no time after oral administration was parent CHO detected in the blood. However, its primary metabolite cyclohexane-1,2-diol was present for different lengths of time depending on the dose. Four metabolites were detected and identified in mouse urine by MS: cyclohexane-1,2-diol; cyclohexane-1,2-diol-O-glucuronide; N-acetyl-S-(2-hydroxycyclohexyl)-L-cysteine; and cyclohexane-1,2-diol-O-sulfate. The sulfate conjugate was not present in rat urine. Topical application of [14C]CHO (60 mg/kg) provided poor absorption in both species. The majority of 14C-equivalents applied dermally were recovered from the charcoal skin trap (approximately 90% of the dose). Only 4% of the dose was absorbed, and the major route of elimination was via the urine. To evaluate the toxicity of CHO, animals were given daily doses of CHO orally and topically for 28 days. No statistically significant changes in final body weights or relative organ weights were noted in rats or mice treated orally with CHO up to 100 mg/kg or up to 60 mg/kg when given topically. Very few lesions were found at necropsy, and none were considered compound related. In conclusion, regardless of route, CHO is rapidly eliminated and excreted into the urine. Furthermore, after either oral or dermal administration, it is unlikely that CHO reaches the systemic circulation intact due to its rapid metabolism, and is therefore unable to cause toxicity in the whole animal under the test conditions used in this study.

Postoperative immunotherapy for patients with hepatocarcinoma using tumor-infiltrating lymphocytes

OBJECTIVE

To explore a more effective immunotherapy for cancer by studying tumor-infiltrating lymphocytes (TIL) of patients with hepatocarcinoma.

METHODS

TIL isolated from freshly resected tumors of 12 patients with hepatocarcinomas were activated, expanded and cultured in vitro by incubation with interleukin-2, and then infused to the patients. The TIL cytotoxicity and phenotype were determined by MTT and immunohistochemical ABC methods.

RESULTS

The average weight and number of cells of the tumor tissues for culture of TIL were 4.8 g and 5.8 x 10(7) respectively, and the median expansion time was 31.8 days in vitro. The maximal expansion achieved 1000 fold, and the mean amplification rate was 198.5 fold. Lymphokine-activated killer cell culture supernatant could stimulate TIL growth. Ten of 12 patients received immunotherapy of TIL. The number of cells infused reached 4 x 10(8)-1.1 x 10(10). In 3 cases of our series, TIL infusions were done through a drug pump with a catheter embedded in the hepatic artery. Eight patients whose primary hepatic carcinomas were resected completely were followed up for 16 months with only one case (12.5%) having recurrence. The recurrence rates of them at 6 and 12 months after tumor resection were remarkably lower than those of the patients who did not receive TIL infusion (19.4% and 41.6%, respectively). One patient whose tumor was not able to be removed received TIL infusion twice and local alcohol injection several times. He has been alive for 9 months.

CONCLUSIONS

TIL isolated from the tumors of patients with hepatocarcinoma can be activated and expanded in vitro. It demonstrated remarkably cytotoxic activity against tumor targets. TIL infusion is an effective immunotherapy for patients with hepatocarcinoma in reducing recurrence after operation.