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Techniques to characterize attosecond harmonic pulses based on the cross-correlation between harmonic and IR laser pulses are presented. The selfcompression of an attosecond harmonic pulse in the harmonic generation itself has been demonstrated, obtaining near transform-limited attosecond harmonic pulses.

A new series of detailed observations of the Coma cluster of galaxies has been undertaken with the aim of better specifying the intergalactic gas component through high dynamic range, combined-telescope observations of the radio emission from the cluster which detect both the cluster-scale and galaxy-scale emission. By combining these multi-frequency radio maps with a Faraday rotation probe experiment using cluster and background sources, and the published X-ray data, we have been able to estimate the intracluster magnetic field strength independently of the usual assumptions of equipartition. The result is approximately 2 microgauss. We compare the X-ray and radio distributions in detail, and describe how our combined results suggest that acceleration of the relativistic electrons occurs in situ, and we suggest that the conditions in the cluster provide good physical arguments to support this.

A mathematical model is proposed to describe the variation with time of pressure, relative density, and temperature for metal powders during hot compaction. The model includes instantaneous response, equilibrium response, and creep response and is based on a micromechanical (hollow sphere) analysis. However, the development is mostly empirical, based on experimental data from hot compaction of iron powder. The instantaneous and equilibrium responses are described by linear response laws, whereas time dependent densification is described by a power law creep response. The experimental data support these assumptions. Agreement between theoretical curves and experimental data is very good. PM/0500

The densification behaviour of iron and copper powders during die compaction has been simulated with several plastic models and the results compared with actual experimental data. The experimental data of Brown were used to obtain the empirical constants of the Cam–clay model. The Cam–clay model simulates actual behaviour during die compaction significantly better than do the Shima and Fleck models. PM/0750

There is strong evidence that Th1-type cytokines play an important role in the pathogenesis of Behçet's disease (BD). Interleukin (IL)-18 is a proinflammatory cytokine that mediates Th1-polarized immune responses, and elevated levels of IL-18 have been observed in the sera and bronchoalveolar lavage fluid of patients with active BD. Therefore, the aim of this study was to investigate the potential associations of two single nucleotide polymorphisms (SNPs) at positions -137 (G/C) and -607 (C/A) in the promoter region of the IL-18 gene with a susceptibility to BD in the Korean population.Ninety-eight patients with BD and 105 healthy controls were studied. All of the subjects were genotyped using sequence specific PCR. The genotypes and alleles between patients with BD and controls were compared using the chi2 test, together with Yate's correction where appropriate. Haplotype analysis was assessed using the EH program.The genotype and allele distributions of the two SNPs did not differ significantly between patients with BD and controls. The haplotype frequencies of the IL-18 promoter polymorphisms were also similar between patients with BD and controls. However, the frequency of the GG genotype at position -137 was significantly higher in BD patients with ocular lesions than in those without ocular lesions (p = 0.026, pc = 0.048, OR = 4.1).Although the IL-18 gene polymorphisms were not associated with a susceptibility to BD in the Korean population, the patients carrying the GG genotype at position -137 had a higher risk of developing the ocular lesions. Further studies in other populations are required to confirm these results.

Airway complications after anterior cervical surgery are rare but potentially lethal. The purpose of this study was to identify the natural course of prevertebral soft tissue swelling after one- or two-level anterior cervical discectomy and fusion (ACDF) in order to prevent lethal airway obstruction after ACDF. Eighty-seven patients scheduled for one- or two-level ACDF were studied prospectively. Lateral radiographs of the cervical spine were taken preoperatively, postoperatively on the day of surgery and on the first, second, third, fourth, and fifth days after operation. Prevertebral soft tissue was measured from C2 to C6 on cervical spine lateral radiographs. The anteroposterior (AP) thickness of the prevertebral soft tissue was measured at each cervical level from C2 to C6. Prevertebral soft tissue swelling occurred postoperatively and increased markedly on the second day after operation. The maximum swelling was found on the second and third days. In fusions above C5 swelling was most prominent at C2, 3. Gradual decrease in swelling was observed after the fourth postoperative day. Prominent swelling was noted at the second, third, and fourth cervical levels. There was no significant difference in swelling when comparing one-level and two-level ACDF. Only one patient required reintubation (1.1%). In conclusion, in this prospective study of 87 patients fused at one or two levels in the cervical spine peak prevertebral soft tissue swelling was observed on the second and third days after the surgery.

To assess potential associations between Korean Behçet's disease (BD) or other rheumatic diseases with vasculitis and two polymorphisms of the endothelial nitric oxide synthase (eNOS) gene, which include the Glu298Asp polymorphism in exon 7 and a variable number of tandem repeats (VNTR) polymorphism in intron 4.65 patients with BD, 27 with rheumatic diseases with vasculitis, and 80 controls were studied. Analyses of the Glu298Asp polymorphism in exon 7 and VNTR polymorphism in intron 4 of the eNOS gene were made by the polymerase chain reaction (PCR)-restriction fragment length polymorphism technique and PCR genotyping, respectively. Additionally, HLA-B51 typing was performed in the BD group and controls by a two step PCR sequence-specific primers method.Significant differences in Glu298Asp genotype frequencies were found between the BD or vasculitis groups and the controls (BD group v controls: p(corr)=0.006; vasculitis group v controls: p0.001). The Asp298 frequency was much higher in the BD and vasculitis groups than in the controls. Even after stratification of the BD group based on the results of HLA-B51 testing, a significant association of the Glu298Asp polymorphism was still found (p=0.002, Mantel-Haenszel weighted odds ratio 4.3, 95% confidence interval 1.7 to 10.9). Distribution of the genotype frequencies in two eNOS gene polymorphisms was similar in connective tissue diseases-associated vasculitis and primary vasculitic syndromes. In contrast, distribution of alleles and genotypes of VNTR polymorphism did not differ between BD or vasculitis groups and the controls.The Glu298Asp polymorphism in exon 7 of the eNOS gene seems to be a susceptibility gene for Korean BD and other rheumatic diseases.

Delayed vertebral collapse after osteoporotic spinal fractures may cause progressive kyphosis, neurological deficits, and chronic back pain. We treated 14 consecutive patients with posterolateral decompression and posterior reconstruction and followed them over a period ranging from 24 to 54 months. The mean age was 67 (range: 62-72) years and the fracture level was T12 and L1. Seven patients were graded as Frankel stage C and seven as stage D. The mean segmental kyphotic angle was 22.6 degrees (7-29 degrees ) preoperatively, 4.4 degrees (1-6 degrees ) postoperatively, and 6.8 degrees (2-15 degrees ) at the final follow-up. The pain score on a visual analogue scale improved from 9.5 preoperatively to 2.7 postoperatively, and the neurological status improved in all patients. Bone fusion was present 9 months after operation. Of four surgical complications, two were dural tears, one a superficial infection, and there was one death due to an acute adrenal insufficiency. Posterolateral decompression with posterior reconstruction is a useful treatment for patients with delayed osteoporotic vertebral collapse.

An uniform field space with precision better than 0.1 ppm for 2 cm radius volume, is obtained using a main and four auxiliary current sources. The main 1 A current has been stabilized to 0.1 ppm by using the Cs atoms magnetic resonance technique.

An atomic magnetic resonance based current source has been developed for a new measurement of the proton gyromagnetic ratio in low field. The high-stability current source is realized by the application of more precise magnetic-field-to-frequency converter. We used the method of /sup 4/He metastable spin polarization through optical pumping of Cs atoms, and also a newly designed two-layer solenoid for the purpose. The drift of current is less than 0.1 ppm/h and its random standard deviation is 0.05 ppm.

The prostaglandin-evoked cAMP production was studied in human neuroblastoma SK-N-BE(2)C cells during neuronal differentiation induced by all-trans retinoic acid. The incubation with 5 microM all-trans retinoic acid for 4-6 days promoted neurite outgrowth of cells. After differentiation, prostaglandin E(2) (PGE(2))-induced cAMP production was dramatically increased, whereas forskolin- and AlF-induced cAMP productions were not changed. The increase reached maximum after 4-days of incubation with all-trans retinoic acid. The differentiation caused an increase in the maximal response and a decrease in the half-maximal effective concentration of the PGE(2)-induced cAMP production. In addition, the binding of [(3)H]PGE(2) to membrane receptors was enhanced in differentiated cells. However, the order of potency of the various prostaglandins (PGE(1) = PGE(2)PGD(2) = PGF(2alpha) = PGI(2)) in cAMP production did not change during the differentiation, suggesting that mainly E-prostanoid (EP) receptors were involved. Butaprost, an EP(2) receptor specific agonist, increased the cAMP level in a concentration dependent manner and had a similar potentiating effect on cAMP production as PGE(2) upon differentiation. Northern blot analysis using the human cDNA probes shows that the EP(2) mRNA level was about seven times higher in differentiated cells, while the dopamine beta-hydroxylase (DBH) mRNA completely disappeared. Our results, thus, suggest that elevated gene expression of the prostanoid EP(2) receptor results in an increase in the PGE(2)-evoked cAMP production in SK-N-BE(2)C cells during neuronal differentiation.

1. The adenosine receptor in mouse pinealocytes was identified and characterized using pharmacological and physiological approaches. 2. Expression of the two adenosine receptor subtypes A2B and A3 was detected in mouse pineal glands and PGT-beta cells by polymerase chain reaction and nucleotide sequencing. 3. Adenosine and 5'-N-ethylcarboxamidoadenosine (NECA) evoked cyclic AMP generation but the A2)-selective agonist 2-(4-(2-carboxyethyl)phenylethylamino)adenosine-5'-N-ethylcarboxamideadenosine (CGS 21680) and the A1-specific agonists R-N(6)-(2-phenylisopropyl)adenosine (R-PIA) and N(6)-cyclopentyladenosine (CPA) had little effect on intracellular cyclic AMP levels. The A2B receptor selective antagonists alloxazine and enprofylline completely blocked NECA-mediated cyclic AMP accumulation. 4. Treatment of cells with the A3-selective agonist N(6)-(3-iodobenzyl)-5'-(N-methylcarbamoyl)adenosine (IB-MECA) inhibited the elevation of the cyclic AMP level induced by NECA or isoproterenol in a concentration-dependent manner with maximal inhibition of 40 - 50%. These responses were blocked by the specific A3 adenosine receptor antagonist MRS 1191. Pretreatment of the cells with pertussis toxin attenuated the IB-MECA-induced responses, suggesting that this effect occurred via the pertussis toxin-sensitive inhibitory G proteins. 5. IB-MECA also caused a concentration-dependent elevation in [Ca(2+)]i and IP3 content. Both the responses induced by IB-MECA were attenuated by treatment with U73122 or phorbol 12-myristate 13-acetate. 6. These data suggest the presence of both A2B and A3 adenosine receptors in mouse pineal tumour cells and that the A2B receptor is positively coupled to adenylyl cyclase whereas the A3 receptor is negatively coupled to adenylyl cyclase and also coupled to phospholipase C.

Rhythmic noradrenergic signaling from the hypothalamic clock in the suprachiasmatic nucleus to the pineal gland causes an increase in intracellular cAMP which regulates the circadian fluctuation of melatonin synthesis. The activation of phospholipase C (PLC)-coupled P2Y(2) receptors upon treatment with ATP and UTP exclusively inhibited the isoproterenol-stimulated cAMP production in mouse pineal gland tumor cells. However, the activation of other PLC-coupled receptors including P2Y(1) and bombesin receptors had little or no effect on the isoproterenol-stimulated cAMP production. Also, ATP did not inhibit cAMP production caused by forskolin, prostaglandin E(2), or the adenosine analog NECA. These results suggest a selective coupling between signalings of P2Y(2) and beta(2)-adrenergic receptors. The binding of [(3)H]CGP12177 to beta(2)-adrenergic receptors was not effected by the presence of ATP or UTP. Ionomycin decreased the isoproterenol-stimulated cAMP production, whereas phorbol 12-myristate 13-acetate slightly potentiated the isoproterenol response. Chelation of intracellular Ca(2+), however, had little effect on the ATP-induced inhibition of cAMP production, while it completely reversed the ionomycin-induced inhibition. Treatment of cells with pertussis toxin almost completely blocked the inhibitory effect of nucleotides. Pertussis toxin also inhibited the nucleotide-induced increase in intracellular Ca(2+) and inositol 1,4,5-trisphosphate production by 30-40%, suggesting that the ATP-mediated inhibition of the cAMP generation and the partial activation of PLC are mediated by pertussis toxin-sensitive G(i)-protein. We conclude that one of the functions of P2Y(2) receptors on the pineal gland is the selective inhibition of beta-adrenergic receptor-mediated signaling pathways via the inhibitory G-proteins.

Extracellular ATP exerts a variety of biological actions through several kinds of P2 receptor in HL-60 promyelocytes. We show that stimulation of P2Y2 receptors with ATP and analogs resulted in the inhibition of a subsequently histamine-induced cAMP production and functional differentiation. Treatment of the cells with phorbol 12-myristate 13-acetate also blocked the histamine-mediated cAMP generation just as ATP did. Incubation of the cells with the protein kinase C inhibitor bisindolylmaleimide (GF109203X) abolished the inhibitory effects of extracellular nucleotides, suggesting that protein kinase C may act as an inter-regulator between two receptors. However, ATP did not affect the binding affinity or total binding of [3H]histamine to membrane receptors; it also did not heterologously desensitize H2 receptors. The ATP treatment synergistically elevated the cAMP levels induced directly by forskolin or indirectly by G protein activation after cholera toxin treatment. This indicates that the site of the protein kinase C action is not the G protein or effector enzyme. Co-stimulation of the cells with nucleotides and histamine inhibited histamine-mediated granulocytic differentiation, which was evaluated by looking at the extent of N-formyl-methionyl-leucyl-phenylalanine responses. Taken together, the results demonstrate that extracellular nucleotides are negatively involved in the modulation of histamine signaling via activation of protein kinase C, probably by inhibiting coupling between receptor and G protein.

The regulatory mode of the P2Y(11) purinoceptor-mediated signalling cascades towards phospholipase C and adenylyl cyclase was studied in HL-60 promyelocytes. Treatment with the potent P2Y(11) receptor activator dATP evoked an elevated intracellular Ca(2+) concentration ([Ca(2+)](i)) and inositol 1,4,5-trisphosphate (IP(3)) production that was sustained for longer than 30 min. However, the dATP-induced responses were significantly inhibited by the activation of protein kinase C after a short exposure to phorbol 12-myristate 13-acetate (PMA). dATP also potently stimulated cyclic AMP production with half maximum effect seen at 23+/-7 microM dATP. In addition, a 5-min pretreatment with PMA enhanced the dATP-stimulated cyclic AMP accumulation. PMA potentiated the cyclic AMP production when adenylyl cyclase was activated directly by forskolin or indirectly by G protein activation after cholera toxin treatment. dATP also enhanced the forskolin-mediated cyclic AMP generation. Treatment of the cells with 10 microM U-73122, which almost completely blocked the dATP-stimulated IP(3) production and [Ca(2+)](i) rise, had no effect on cyclic AMP accumulation, while 10 microM 9-(tetrahydro-2-furyl)adenine (SQ 22536), which inhibited the adenylyl cyclase activation, did not effect the dATP-stimulated phosphoinositide turnover. Taken together, the results indicate that P2Y(11) receptor-mediated activation of phospholipase C and adenylyl cyclase occurs through independent pathways and is differentially regulated by protein kinase C in HL-60 cells.

Extensive investigation of vertebrate striated muscle titin has yielded significant insight into its structure and function in striated muscle. We have begun to investigate other members of the titin protein family found in vertebrate smooth muscle and nonmuscle cells. Smooth and nonmuscle titins resemble striated muscle titin in molecular size and morphology but differ in their interactions with myosin II filaments and in the structural contexts in which they exist in vivo. Divergence of these titins from the muscle titin paradigm demonstrates the versatility of this remarkable family of giant proteins.

An enlarged labium minus can be bothersome for functional, aesthetic, and social reasons. Labia minora hypertrophy can be congenital or acquired by chronic irritation, exogenous androgenic hormones, or stretching with weights. This can cause inflammation, poor hygiene, interference with sexual intercourse, or intermittent urinary self-catheterization in myelodysplastic women. Aesthetically, an asymmetric or enlarged labium minus causes self-consciousness sexually and when the subject wears tight pants. Previously, labia minora reduction was performed by amputation of the protuberant segment and oversewing the edge, or a wedge of protuberant labial tissue was excised and reapproximated. However, the former technique removes the natural contour and color of the edge of the labium minus, and the latter can result in an incomplete or tight reduction. Therefore, rather than an amputation or a wedge resection, we preserved the natural contour and anatomy of the labium minus by simply reducing its central width through bilateral deepithelialization and reapproximation of the central portion with preservation of the neurovascular supply to the edge. Six patients have undergone this reduction method with excellent results without specific complications.

Capsaicin has been shown to act through vanilloid receptors, which are temperature-sensitive cation channels. However, there also are indications that suggest the capsaicin effect is not mediated by the vanilloid receptor. We therefore investigated the effect of capsaicin on the phospholipase C-mediated Ca(2+) rise in PC12 cells. Capsaicin caused a rapid decline in extracellular ATP- or bradykinin-induced calcium transients to the basal level without significant attenuation of the peak level. However, capsaicin did not inhibit either ATP- or bradykinin-induced Ca(2+) elevation in the absence of extracellular Ca(2+) or inositol-1,4,5-trisphosphate production. Capsaicin also inhibited ATP-induced norepinephrine secretion. Capsaicin dramatically reduced the thapsigargin-induced sustained Ca(2+) level, suggesting that capsaicin inhibits thapsigargin-sensitive store-operated Ca(2+) entry (SOCE). Thapsigargin-induced Ba(2+) and Mn(2+) influx was also inhibited by capsaicin. Furthermore, capsaicin overlapped SKF96365 in inhibiting thapsigargin-sensitive SOCE. Capsaicin-induced inhibition of SOCE also occurred in thapsigargin-treated Jurkat-T cells, which have a rather prominent SOCE. Resiniferatoxin, a vanilloid receptor agonist, did not mimic the effect of capsaicin. Ruthenium red and capsazepine, which are known to inhibit the vanilloid receptor, did not affect this capsaicin effect. The results suggest that capsaicin does not mediate vanilloid receptor signaling when inhibiting the thapsigargin-sensitive SOCE. The capsaicin action was also not mediated by activation of protein kinase C because phorbol-12-myristate 13-acetate and capsaicin did not overlap each other's effect and GF109203X did not reverse the inhibitory effect of capsaicin. The results suggest that capsaicin negatively modulates thapsigargin-sensitive SOCE subsequent to phospholipase C activation.

1. We investigated responses to neurotensin in human promyelocytic leukaemia HL-60 cells. 2. Neurotensin increased the cytosolic calcium concentration ([Ca2+]i) in a concentration-dependent manner and also produced inositol 1,4,5-trisphosphate (InsP3). 3. Among the tested neurotensin analogues, neurotensin 8-13, neuromedin-N, and xenopsin also increased [Ca2+]i, whereas neurotensin 1-11 and neurotensin 1-8 did not elicit detectable responses. 4. SR48692, an antagonist of NTR1 neurotensin receptors, blocked the neurotensin-induced [Ca2+]i increase, whereas levocabastine, which is known as an NTR2 neurotensin receptor antagonist, did not attenuate the neurotensin-evoked effect. 5. The expression of NTR1 neurotensin receptors was confirmed by Northern blot analysis and reverse transcriptase-polymerase chain reaction (RT-PCR). 6. During 1.25% dimethylsulfoxide (DMSO)-triggered granulocytic differentiation of HL-60 cells, the neurotensin-induced [Ca2+]i rise became gradually smaller and completely disappeared 4 days after treatment with DMSO. The mRNA level for neurotensin receptors was also decreased after differentiation. 7. The results show that HL-60 cells express NTR1 neurotensin receptors and suggest that granulocytic differentiation involves transcriptional regulation of the receptors resulting in down-regulation of the neurotensin-induced signalling.

The effects of temperature on ion fluxes and catecholamine secretion that are mediated by nicotinic acetylcholine receptors (nAChRs), voltage-sensitive calcium channels (VSCCs), and voltage-sensitive sodium channels (VSSCs) were investigated using bovine adrenal chromaffin cells. When the chromaffin cells were stimulated with DMPP, a nicotinic cholinergic agonist, or 50 mM K+, the intracellular calcium ([Ca2+]i) elevation reached a peak and decreased more slowly at lower temperatures. The DMPP-induced responses were more sensitive to temperature changes compared to high K+-induced ones. In the measurement of intracellular sodium concentrations ([Na+]i), it was found that nicotinic stimulation required a longer time to attain the maximal level of [Na+]i at lower temperatures. In addition, the VSSCs-mediated [Na+]i increase evoked by veratridine was also reduced as the temperature decreased. The measurement of [3H]norepinephrine (NE) secretion showed that the secretion within the first 3 min evoked by DMPP or high K+ was greatest at 37 degrees C. However, at 25 degrees C, the secretion evoked by DMPP, but not that by the 50 mM K+, was greater after 10 min of stimulation. This data suggest that temperature differentially affects the activity of nAChRs, VSCCs, and VSSCs, resulting in differential [Na+]i and [Ca2+]i elevation, and in the [3H]NE secretion by adrenal chromaffin cells.

1. The adrenoceptor in a mouse pineal gland tumour cell line (PGT-beta) was identified and characterized using pharmacological and physiological approaches. 2. Adrenaline and noradrenaline, adrenoceptor agonists, stimulated cyclic AMP generation in a concentration-dependent manner, but had no effect on inositol 1,4,5-trisphosphate production. Adrenaline was a more potent activator of cyclic AMP generation than noradrenaline, with half maximal-effective concentrations (EC50) seen at 175+/-22 nM and 18+/-2 microM for adrenaline and noradrenaline, respectively. 3. The addition of forskolin synergistically stimulated the adrenaline-mediated cyclic AMP generation in a concentration-dependent manner. 4. The pA2 value for the specific beta2-adrenoceptor antagonist ICI-118,551 (8.7+/-0.4) as an antagonist of the adrenaline-stimulated cyclic AMP generation were 3 units higher than the value for the betaI-adrenoceptor antagonist atenolol (5.6+/-0.3). 5. Treatment of the cells with adrenaline and forskolin evoked a 3 fold increase in the activity of serotonin N-acetyltransferase with the peak occurring 6 h after stimulation. 6. These results suggest the presence of beta2-adrenoceptors in mouse pineal cells and a functional relationship between the adenylyl cyclase system and the regulation of N-acetyltransferase expression.

A new series of detailed observations of the Coma cluster of galaxies has been undertaken with the aim of better specifying the intracluster gas component throgh high dynamic range, combined-telescope observations of the radio halo emission from the cluster which detect both the cluster-scale and galaxy-scale emission. By combining these multi-frequency maps with a Faraday rotation probe experiment using cluster and background sources, and the published X-ray data, we have been able to estimate the intracluster magnetic field strength independently of the unusal assumption of equipartition. The result is approximately 2 microgauss and the tangling of the rms field occurs on an optical galaxy scale.

The Coma cluster is a rich cluster of galaxies nested in an even larger supercluster of galaxies. The plane of the supercluster appears to be defined by the Coma cluster itself and another galaxy cluster, Abell 1367, that lies about 40 Mpc (H0 = 75 Mpc km−1s−1 (≡h75)) farther west (Tifft and Gregory 1976).

We investigated the effects of neomycin on nicotinic acetylcholine receptor-induced responses in bovine adrenal chromaffin cells. Neomycin inhibited the nicotinic agonist dimethylphenylpiperazinium iodide (DMPP)-induced norepinephrine secretion in a concentration-dependent manner. Neomycin had also an inhibitory effect on the DMPP-induced increase in cytosolic Ca++ concentration ([Ca++]i). This effect was further confirmed by inhibition of the DMPP-induced fluorescence quenching of fura-2 upon Mn++ entry. Under the same conditions, however, neomycin did not change the bradykinin-induced [Ca++]i increase, which follows the downstream signal of phospholipase C phospholipase C activation in this cell. The inhibitory effect of neomycin on the DMPP-induced [Ca++]i increase was apparent when the neomycin treatment was performed simultaneously with DMPP, suggesting a direct action on the nicotinic receptor. The direct inhibitory action of neomycin on the nicotinic receptor was also evident when neomycin inhibited the DMPP-induced cytosolic Ca++ increase, which is not affected by nifedipine nor omega-conotoxin MVIIC, and the cytosolic Na+ increase, which is not affected by tetrodotoxin. In addition, we observed that neomycin inhibited the binding of nicotine to the acetylcholine receptor in a noncompetitive manner. The data suggest that neomycin inhibits the nicotinic acetylcholine receptor directly, which results in blockage of the nicotinic receptor-mediated signaling without involvement of phospholipase C.

Mastoparan, a peptide toxin from wasp venome, mimics receptors by stimulating the GTPase activity of guanine nucleotide binding proteins and the G-protein-coupled phospholipase C (PLC). By using Mas-7, the active analog of mastoparan, we showed that it makes pores in the plasma membrane. Treatment with Mas-7 but not Mas-17, the inactive analog, produced a concentration-dependent rise in intracellular Ca2+ concentration ([Ca2+]i) and facilitated the uptake of ethidium bromide (EtBr) (314 Da) to a sustained level during the stimulation. In addition, Mas-7 triggered the influx of lucifer yellow (457 Da), while it did not induce the influx of fura-2 (831 Da) and Evans blue (961 Da). However, the Mas-7-induced permeability was selectively prevented by the addition of La3+, Ni2+, and Co2+, but not Cd2+. This blocking activity was concentration-dependent. While the stimulatory effect of Mas-7 on PLC activity was dependent on extracellular Ca2+, the pore forming activity of Mas-7 was not effected by removal of extracellular Ca2+. These results, therefore, suggest that the mastoparan's action in pore formation is independent from its action in PLC stimulation and is negatively effected by inorganic cations.

We investigated the effects of amitriptyline, a tricyclic antidepressant, on [3H]norepinephrine ([3H]NE) secretion and ion flux in bovine adrenal chromaffin cells. Amitriptyline inhibited [3H]NE secretion induced by 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP) and 70 mM K+. The half maximal inhibitory concentration (IC50) was 2 microM and 9 microM, respectively. Amitriptyline also inhibited the elevation of cytosolic calcium ([Ca2+]i) induced by DMPP and 70 mM K+ with IC50 values of 1.1 microM and 35 microM, respectively. The rises in cytosolic sodium ([Na+]i) and [Ca2+]i induced by the Na+ channel activator veratridine were also inhibited by amitriptyline with IC50 values of 7 microM and 30 microM, respectively. These results suggest that amitriptyline at micromolar concentrations inhibits both voltage-sensitive calcium (VSCCs) and sodium channels (VSSCs). Furthermore, submicromolar concentrations of amitriptyline significantly inhibited DMPP-induced [3H]NE secretion and [Ca2+]i rise, but not veratridine- or 70 mM K+-induced responses, suggesting that nicotinic acetylcholine receptors (nAChR) as well as VSCCs and VSSCs can be targeted by amitriptyline. DMPP-induced [Na+]i rise was much more sensitive to amitriptyline than the veratridine-induced rise, suggesting that the influx of Na+ and Ca2+, through the nAChR itself is blocked by amitriptyline. Receptor binding competition analysis showed that binding of [3H]nicotine to chromaffin cells was significantly affected by amitriptyline at submicromolar concentrations. The data suggest that amitriptyline inhibits catecholamine secretion by blocking nAChR, VSSC, and VSCC.

Dopamine beta-hydroxylase (DBH), the enzyme catalyzing the conversion of dopamine to norepinephrine, is specifically expressed in adrenergic and noradrenergic neurons in the central nervous system. DNase I hypersensitive sites were found in the 5'-flanking region of the DBH gene in noradrenergic human neuroblastoma SK-N-BE(2)C cells, but not in DBH-nonexpressing HeLa cells. We report here that the 4.3-kilobase upstream sequence of the human DBH gene confers cell type-specific expression as assessed by transient expression assay. Furthermore, deletional and mutational analyses revealed two genetic regulatory elements required for the regulation of cell type specificity. First, deletion of the cAMP-response element (CRE) abolished95% of the transcriptional activity by the DBH upstream promoter, thus implicating the CRE as an essential positive genetic element. Second, deletion of a region between -490 and -263 base pairs resulted in 10-fold increase of reporter gene activity only in HeLa cells, indicating that this region contains a cell-specific silencer. A 13-base pair fragment residing within that region shows 77% sequence identity with the neuron-specific silencer motif recently identified in two neuronal genes, i.e. SCG10 and type II sodium channel genes. We propose that the interplay between the CRE and this neuron-specific silencer region plays an important role in the tissue-specific expression of the DBH gene in noradrenergic cells.

This work is devoted to the investigation of the discharge characteristics of an ac arc plasma torch with a well-type cathode working in air and CO2. The electrical characteristics, plasma jet image and optical emission profile are investigated by varying the discharge power and the gas flow rate. The dynamic behaviour of arc voltage and current is characterized by smooth-shaped waveforms, regularly iterated with a driving frequency. The moving of arc spot positions is inferred from the measured waveforms, and compared with that observed in dc torches. A simple lifetime test is performed to verify the speculation that the arc spots in ac operation move continuously over a wide region with a very high speed. The result shows that the electrode lifetime can be enhanced by combining the vortex motion of arc gas with the ac driving.

Flavonoid has anti-oxidant properties and has been shown to protect cells against oxygen radical damage. This study therefore, evaluated the effect of flavonoid on the in vitro development ability of porcine embryos produced by parthenogenesis (PA) or somatic cell nuclear transfer (SCNT). Porcine embryos were produced from abattoir-derived prepubertal oocytes either by PA or SCNT of fetal fibroblast into enucleated oocytes essentially as we described earlier (Gupta et al. 2008 Mol. Reprod. Dev. 75, 588–597). One-cell embryos were subsequently cultured in NCSU23 + 0.4% polyvinyl alcohol supplemented with or without 10 μm flavanoid for 7 days at 39°C in a humidified atmosphere of 5% CO2 in air. Results showed that the presence of flavonoid in the culture medium increased (v. controls) the rate of blastocyst in both PA (31.7 ± 4.0 v. 20.4 ± 2.0%) and SCNT (20.6 ± 2.5 v. 12.2 ± 2.9%) groups, respectively (P < 0.05). These blastocysts also had higher ability to hatch (PA: 53.7 ± 3.6 v. 34.0 ± 2.4%; SCNT: 70.9 ± 2.5 v. 45.7 ± 2.9%) and contained higher cell number (PA: 38.9 ± 2.0 v. 31.3 ± 2.1; SCNT: 37.5 ± 2.0 v. 29.7 ± 2.5) than those of control groups (P < 0.05). Western blot analysis of parthenogenetic blastocysts showed that, flavonoid also reduced the expression of caspase-3 and p38 mitogen-activated protein kinase (MAPK) proteins by 3.1 ± 0.1 and 7.7 ± 0.2 fold, respectively while expression of ERK1/2 protein was increased by 4.7 ± 2.3 fold. The 2′,7′-dichlorofluorescene fluorescence staining of embryos further revealed that the activity of reactive oxygen species (ROS) was significantly reduced in flavonoid treated embryos by 2 fold(P < 0.05). These data therefore, suggest that flavonoid may improve the in vitro development rate and quality of porcine embryos by reducing ROS activity and change in protein expression.

Survival rate over a 5-year period were studied in a series of 658 proven primary lung cancer patients treated by thoracic surgeons at 8 institutes during the period from 1976 to 1987 in Korea. The study was designed as a multi-center cooperative work for the statistical analysis of the followup result. Clinical data of age, sex, morbidity, and staging of the tumor were assessed in 540 patients to evaluate their 5-year survival rates. Eventually, 405 resectable patients were analyzed by stage, cell type, surgical procedure, and TNM status. The 5-year actuarial survival rates by stage in the resectable group were: stage I 39.7%, II 30.6% III A 16.3%, III B 6.7%, and IV 0%. The 5-year survival rates by cell type were: squamous cell 31.9%, adenocarcinoma 21.2%, large cell 11%, and small cell 6%. The survival rates by surgical procedures were: lobectomy 30.7% and pneumonectomy 25.7%. The survival rates by TNM status in the operable group were: T1 34.7%, T2 26.8%, T3 7.5%, T4 5%; N1 23%, N2 10%, N3 3%; MO 21%, and M1 0%, respectively. The overall actuarial 5-year survival rate in the group of 405 resectable patients was 25.9%.

The periodontium, especially the periodontal ligament and alveolar bone, are tissues constantly subjected to physical stress such as occlusion and mastication. This study was designed to explore the effect of the pulsed electromagnetic fields (PEMF) on the cell attachment and the spread of human periodontal ligament fibroblasts (HPLF) and rat osteoblasts (ROB). PEMF are categorized as one type of mechanical stress. HPLF were obtained by the explantation method described by Saito et al. They were then subcultured in Dulbecco's modified Eagle's medium (D-MEM) and supplemented with 2 mg/ml dialyzed fetal calf serum protein (FCSP), 50 micrograms/ml ascorbic acid and penicillin/streptomycin after trypsinization. ROB were isolated from a two-day-old rat calvaria by the sequential bacterial collagenase digestion method described by Dziak and Brand and were subcultured in D-MEM supplemented with FCSP, ascorbic acid and penicillin/streptomycin. After the confluent HPLF were cultured with serum-free MCDB 107 medium, the quiescent HPLF were exposed with or without PEMF for 24 hr. This was followed by the collection of the control conditioned medium (C-CM) and PEMF exposed conditioned medium (PEMF-CM). The cell attachment assay was performed so that the hydrophobic 24 multiwells were coated with the whole conditioned medium or fractionated conditioned medium by a PO-60K column. After coating, heat inactivated BSA blocked nonspecific sites for cell adhesion, and 3H-TdR labeled HPLF or ROB were cultured on the precoated wells. The activity of cell attachment and spreading was determined by the radioactivity of 3H-TdR using a scintillation counter. The characters of cell attachment factors derived from HPLF were hydrophobic, heat labile and proteolytic enzyme digestible. In addition, the fractionated PEMF-CM enhanced the spreading activity of ROB. PEMF induced the 10 KDa which can enhance the HPLF and ROB spreading. Therefore, the cell attachment and spreading factors secreted by HPLF exposed with PEMF may regulate HPLF and also ROB.

Recent studies suggest that thallium-201 (201Tl) planar scans of brain tumors more accurately reflect viable tumor burden than CT, MRI, or radionuclide studies with other single-photon emitting compounds. We have previously reported the utility of 201Tl SPECT index in distinguishing low- from high-grade gliomas elsewhere. Here we describe the technical considerations of deriving a simple 201Tl index, based on uptake in the tumor normalized to homologous contralateral tissue, from SPECT images of brain tumors. We evaluated the importance of consistently correcting for tissue attenuation, as it may achieve better lesion discrimination on qualitative inspection, and the methodologic limitations imposed by partial volume effects at the limits of resolution.

We developed a virtual model of a Josephson junction series array based on a rigorous dynamic simulation and investigated coupling effect of Josephson oscillations. Our virtual model for a superconductor-insulator-normal metal-insulator-superconductor junction array reveals that a time-lag junction instability should be avoided for global synchronization in a long array with a large number of junctions. We found that the coupling between the self-generated Josephson oscillations through a microwave transmission line plays an important role in the collective synchronization of the Josephson array.