Anomalous muscles and nerves in the hand of a 94-year-old cadaver-A case report

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The additional flexor muscle (Flexor Digiti Minimi Longus m.) passing through Guyon’s canal is the first to be described.

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The anomalous first lumbrical muscle with three origins is the first to be described.

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Berretini’s and Kaplan’s anastomosis was also noted.

Introduction

During an anatomical dissection of the distal upper extremities, numerous muscular and nervous anomalies were found in the forearm and hand of a 94-year-old cadaver. These anomalies are clinically relevant with regard to medical or surgical interventions.

Presentation of case

The presence of a “flexor digiti minimi longus” muscle was observed passing through Guyon’s canal; to our knowledge this passageway has never been previously reported. An aberrant first lumbrical with three origins was noted. Additionally, numerous atypical nerves were found innervating the hand; the dorsal branch of the ulnar nerve contributed to cutaneous innervation of the palm of the hand (Kaplan’s anastomosis), the superficial ulnar nerve provided muscular innervation to the flexor digiti minimi brevis muscle, and two connections between the common palmar digital branches of the median and superficial ulnar nerves were observed (Berrettini anastomosis).

Discussion

Here, we describe an extranumerary muscle associated with the hypothenar group of muscles. We also describe unusual origins of the first lumbrical muscle, and atypical cutaneous and muscular innervation to the palm of the hand.

Conclusion

Clinically, understanding the existence of these anatomical variations may influence medical care or surgical procedures.

Development of a transposon-based marker system for mutation breeding in sorghum (Sorghum bicolor L.)

Under certain circumstances, transposable elements (TE) can create or reverse mutations and alter the genome size of a cell. Sorghum (Sorghum bicolor L.) is promising for plant transposon tagging due to its small genome size and its low content of repetitive DNA. We developed a marker system based on targeted region amplification polymorphisms (TE-TRAP) that uses the terminal inverted repeats (TIRs) of transposons. A total of 3816 class 2 transposons belonging to the PIF/Harbinger family were identified from the whole sorghum genome that produced five primers, including eight types of TIRs. To define the applicability and utilization of TE-TRAP, we used 21 individuals that had been bred after ɤ-ray irradiation. In total, 31 TE-TRAP, 16 TD, and 21 AFLP primer combinations generated 1133, 223, and 555 amplicons, respectively. The percent polymorphic marker was 62.8, 51.1, and 59.3% for the TE-TRAP, TD, and AFLP markers, respectively. Phylogenetic and principal component analyses revealed that TE-TRAP divided the 21 individuals into three groups. Analysis of molecular variance suggested that TE-TRAP had a higher level of genetic diversity than the other two marker systems. After verifying the efficiency of TE-TRAP, 189 sorghum individuals were used to investigate the associations between the markers and the ɤ-ray doses. Two significant associations were found among the polymorphic markers. This TE-based method provides a useful marker resource for mutation breeding research.

Chemical and genetic diversity of high-seed-yield sorghum (Sorghum bicolor M.) germplasms

This study evaluated the chemical and genetic diversity of high-seed-yield sorghum germplasms from Korea, the United States, and South Africa. We identified significant differences in the chemical contents of whole plants at the heading stage in all cultivars, including differences in crude protein, fat, fiber, ash, neutral detergent fiber, acid detergent fiber, mineral, and fatty acid contents. Our results suggest that Banwoldang is the most appropriate cultivar for roughage because of its high protein yield. We identified significant differences in the tannin, flavonoid, amylose, mineral, crude fat, fatty acid, and 3-deoxyanthocyanin contents in the whole grain from all cultivars, but not in the mineral or crude fat contents. Tannin levels were generally low. IS645 contained the highest levels of flavonoids and linolenic acid compounds, and Moktak had the highest amylose and deoxyanthocyanidin content in the grain. To assess genetic diversity, we used 10 simple sequence repeat (SSR) primer sets to identify 38 alleles with 3-8 alleles per locus. Based on phylogenetic analysis of the SSR markers, the sorghum cultivars were divided into three major groups. Comparison of clusters based on chemical compositions with those based on SSRs showed that the groups formed by the three native Korean cultivars clustered similarly in molecular dendrograms. Association analysis was conducted for the 10 SSR marker; 48 chemical and growth traits were present for two marker traits (seed color and whole plant fatty acid content) with significant marker-trait associations. These markers could be used to select sorghum cultivars for breeding programs.

Effects of age, replicative lifespan and growth rate of human nucleus pulposus cells on selecting age range for cell-based biological therapies for degenerative disc diseases

Autologous disc cell implantation, growth factors and gene therapy appear to be promising therapies for disc regeneration. Unfortunately, the replicative lifespan and growth kinetics of human nucleus pulposus (NP) cells related to host age are unclear. We investigated the potential relations among age, replicative lifespan and growth rate of NP cells, and determined the age range that is suitable for cell-based biological therapies for degenerative disc diseases. We used NP tissues classified by decade into five age groups: 30s, 40s, 50s, 60s and 70s. The mean cumulative population doubling level (PDL) and population doubling rate (PDR) of NP cells were assessed by decade. We also investigated correlations between cumulative PDL and age, and between PDR and age. The mean cumulative PDL and PDR decreased significantly in patients in their 60s. The mean cumulative PDL and PDR in the younger groups (30s, 40s and 50s) were significantly higher than those in the older groups (60s and 70s). There also were significant negative correlations between cumulative PDL and age, and between PDR and age. We found that the replicative lifespan and growth rate of human NP cells decreased with age. The replicative potential of NP cells decreased significantly in patients 60 years old and older. Young individuals less than 60 years old may be suitable candidates for NP cell-based biological therapies for treating degenerative disc diseases.

Relative adrenal insufficiency in chronic liver disease: its prevalence and effects on long-term mortality

BACKGROUND

The relationship between relative adrenal insufficiency (RAI) and chronic liver disease is unclear.

AIM

To determine the frequency with which RAI is observed in noncritically ill patients at various stages of chronic liver disease, and the correlation between RAI and disease severity and long-term mortality.

METHODS

In total, 71 non-critically ill patients with liver cirrhosis (n = 54) and chronic hepatitis (n = 17) were evaluated prospectively. A short stimulation test (SST) with 250 μg of corticotrophin was performed to detect RAI. RAI was defined as an increase in serum cortisol of <9 μg/dL in patients with a basal total cortisol of <35 μg/dL.

RESULTS

RAI was observed in only 13 (24.1%) of 54 patients with cirrhosis. Compared to those without RAI, cirrhotic patients with RAI had significantly higher Child-Turcotte-Pugh score (10.3 ± 1.7 vs. 7.1 ± 1.8, mean ± s.d., P < 0.001) and Model for End-Stage Liver Disease score (14.5 ± 6.6 vs. 9.4 ± 3.7, P = 0.017). The cortisol response to corticotropin was negatively correlated with the severity of cirrhosis (P < 0.05). In addition, the mortality rate was higher in cirrhotic patients with RAI (69.2%) than in those without RAI (4.9%; P < 0.001) during the follow-up period of 20.1 ± 13.5 months (range, 5.8-51.1 months). The cumulative 1-year survival rates in cirrhotic patients with and without RAI were 69.2% and 95.0%, respectively (P = 0.05), while the corresponding cumulative 3-year survival rates were 0% and 95.0% (P < 0.001).

CONCLUSIONS

Relative adrenal insufficiency is more commonly observed in those with severe cirrhosis, and is clearly associated with more advanced liver disease and a shortened long-term survival. This suggests that relative adrenal insufficiency is an independent prognostic factor in non-critically ill patients with cirrhosis.

Serum IP-10 Levels Correlate with the Severity of Liver Histopathology in Patients Infected with Genotype-1 HCV

BACKGROUND/AIMS

Interferon-γ-inducible protein 10 (IP-10) plays important roles in the pathogenesis of hepatitis C virus (HCV) infection. We investigated the association between serum IP-10 levels and liver pathology in patients with chronic HCV infection.

METHODS

The serum IP-10 concentration was assessed in 85 patients with chronic HCV infection using a solid phase sandwich enzyme-linked immunosorbent assay, and a liver biopsy specimen was obtained. The pathology was scored using the Knodell histologic activity index (HAI).

RESULTS

Of the 85 patients, 58 had genotype 1 HCV infection, 21 had genotype non-1, and 6 were undetermined. The serum IP-10 levels did not differ between patients infected with genotype 1 and genotype non-1 (p=0.472). In patients with genotype 1 infection, the total HAI score and the stage of fibrosis were highly correlated with the serum IP-10 level (r=0.555, r=0.578, p<0.001). Furthermore, the serum IP-10 concentrations of patients with severe fibrosis (stages 3, 4) were higher than those of patients with mild fibrosis (stages 0 to 2; 214.4 vs. 72.3 pg/mL, p=0.002) among patients with genotype 1 infection. However, in patients without genotype 1 infection, the histopathology was not associated with the serum IP-10 level. A multivariate analysis showed that serum IP-10 was an independent predictor of fibrosis (stages 3, 4) in patients with genotype 1 infection (odds ratio, 1.034; 95% confidence interval, 1.006 to 1.064; p=0.018).

CONCLUSIONS

Serum IP-10 concentration was significantly correlated with the severity of liver histology in genotype 1 HCV infection.

[Durability of sustained virologic response in chronic hepatitis C: analysis of factors related to relapse after sustained virologic response with peginterferon plus ribavirin combination therapy]

BACKGROUND/AIMS

Pegylated interferon plus ribavirin combination therapy has been the standard of therapy for patients with chronic hepatitis C. Although previous studies have reported long term durability after the sustained virologic response (SVR) with standard therapy for chronic hepatitis C, it is still unclear in Korea. The aim of this study was to evaluate the relapse rate and related factors after SVR to pegylated interferon therapy in Korean patients with chronic hepatitis C.

METHODS

A total of 119 chronic hepatitis C patients were treated with pegylated interferon plus ribavirin, and 73 patients achieved SVR (61.3%). Among 73 patients who achieved SVR, 68 patients (genotype 1, n=40; genotype non-1, n=28) were evaluated for virological response after SVR.

RESULTS

SVR rate in genotype 1 and genotype non-1 were 52.5%, and 65.1%, respectively. Relapse after SVR occurred in 5 patients (7.4%) with genotype 1, and the median time to relapse from SVR was 10 months. Univariate analysis revealed that the dose reduction of pegylated interferon (p=0.005) and cirrhosis (p=0.03) were significantly associated with relapse.

CONCLUSIONS

These results suggested that the relapse could occur even after SVR achievement in Korean patients with chronic hepatitis C, and the dose reduction of pegylated interferon during treatment or having cirrhosis may increased the risk for relapse.

Expression and immunohistochemical localization of TMEM16A/anoctamin 1, a calcium-activated chloride channel in the mouse cochlea

Sound transduction in the cochlea depends on the unique high concentrations of K(+) in the endolymph. The production and maintenance of high K(+) concentrations are accompanied by Cl(-) cycling. In this study, we report on an investigation of the expression and localization of TMEM16A/anoctamin 1 (ANO1), a recently cloned Ca(2+)-activated Cl(-) channel, in the mouse cochlea by Western blot and immunhistochemistry. The ANO1 protein was identified in the cochlea by Western blotting. The immunoreactivity was found in stria vascularis as a line and in the organ of Corti as three plaques. The cellular localization of ANO1 was examined by means of double-labeling experiments with anti-claudin 11, a marker for basal cells of the stria vascularis. The results demonstrated that ANO1 colocalized with claudin 11, indicating its expression in basal cells. We also examined ANO1 localization in the organ of Corti by double- and triple-labeling techniques with anti-myosin VI, a marker for hair cells, and anti-synaptophysin, a marker for olivocochlear efferent nerve endings under hair cells. The results clearly showed that ANO1 is colocalized with synaptophysin, but not with myosin VI, indicating that ANO1 is localized at medial olivocochlear efferent nerve endings under outer hair cells. These results suggest that ANO1 may be specifically involved in synaptic transmission from medial olivocochlear efferent nerve endings to outer hair cells in the organ of Corti, as well as Cl(-) cycling in basal cells of the stria vascularis.

Simultaneous effect of ursolic acid and oleanolic acid on epidermal permeability barrier function and epidermal keratinocyte differentiation via peroxisome proliferator-activated receptor-alpha

Ursolic acid (UA) and oleanolic acid (ONA) are pentacyclic triterpenoids, which naturally occur in many medicinal herbs and plants. Recent research revealed that several pharmacological effects could be attributed to UA and ONA, such as anti-tumor, anti-inflammatory and anti-microbial activities. To evaluate the effects of UA and ONA on epidermal permeability barrier recovery and normal skin, both flanks of hairless mice were topically treated with either 0.01-0.1 mg/mL UA or 0.1-1.0 mg/mL ONA after tape stripping and transepidermal water loss (TEWL) were assessed, and then hydration and TEWL were measured for 3 weeks with application of UA and ONA (2 mg/mL). We also investigated the morphological changes using light (LM) and electron microscopic (EM) examination. Finally, we observed that UA and ONA stimulated epidermal keratinocyte differentiation via peroxisome proliferator-activated receptor (PPAR)-alpha using Western immunoblotting. The recovery rate of epidermal permeability barrier after tape stripping increased in the UA- and ONA-treated groups (0.1 mg/mL UA and 0.5 mg/mL ONA) at 6 h to more than 20% when compared to the vehicle-treated group (P < 0.05). In both groups, hydration was increased compared to the vehicle group from 1 week without TEWL alteration (P < 0.05). An LM finding showed that epidermal thickening was frequently observed (UA > ONA > vehicle). EM examination revealed an increase in secretion and in the number of lamellar bodies in treated groups and that complete formation of lipid bilayers was also prominent (ONA > UA > vehicle). Protein expression of PPAR-alpha, involucrin, loricrin and filaggrin increased twofold and threefold in HaCaT cells treated for 24 h with either ONA (10 micromol/L) or UA (10 micromol/L), respectively, reflecting that the UA and ONA can improve the recovery of skin barrier function and induce epidermal keratinocyte differentiation via PPAR-alpha. Taken together, these results suggest that UA and ONA will be pertinent candidates for the improvement of epidermal permeability barrier function.

Phenylpropanolamine contained in cold remedies and risk of hemorrhagic stroke

In this study, we sought to elucidate whether phenylpropanolamine (PPA) in cold remedies (small and divided doses) increases the risk of hemorrhagic stroke (HS). PPA exposure significantly increased the risk, and the risk was much higher in women. In women, linear trends were also found in recency, duration, and dosage of PPA exposure. PPA contained in cold remedies increases the risk of HS, particularly in women.

Comparative study between propofol in a long-chain triglyceride and propofol in a medium/long-chain triglyceride during sedation with target-controlled infusion

This study was performed to compare the pharmacological characteristics of propofol in an emulsion of both medium- and long-chain triglycerides (MCT/LCT) with those of propofol in an LCT emulsion, by measuring the sedative level and the plasma concentration of propofol during sedation using a target-controlled infusion (TCI) technique. Forty ASA 1 or 2 adult patients who required spinal anaesthesia for surgery were enrolled in this study. The patients were divided into two groups: a propofol LCT group (n = 20) and a propofol MCT/LCT group (n = 20). Propofol was injected intravenously at target blood concentrations of 2.0, 3.0 and 4.0 microg x ml(-1). The bispectral (BIS) index was recorded, and arterial blood was drawn to measure the actual plasma concentrations of propofol at each predicted concentration. Propofol was assayed by high-performance liquid chromatography. Propofol MCT/LCT was associated with significantly less pain than propofol LCT (P < 0.05). There were no significant differences between the two groups in BIS index or in plasma concentration of propofol at each predicted concentration. Computer-generated TCI of propofol MCT/LCT during sedation is comparable with that of propofol LCT with respect to pharmacokinetics and pharmacodynamics. The formulation of MCT/LCT has a beneficial effect with respect to less pain on injection.

Functional and genetic assessment of IFN-gamma receptor in patients with clinical tuberculosis

OBJECTIVE

The molecular basis of the genetic vulnerability underlying the most common form of clinical tuberculosis (TB) remains largely unknown. We speculated that mild genetic defects in the interferon-gamma (IFN-gamma) signalling pathway caused a subtle functional impairment of IFN-gamma which would explain susceptibility to Mycobacterium tuberculosis in clinical TB.

DESIGN

A case-control study.

RESULTS

We evaluated functional responsiveness to IFN-gamma in monocytes from patients with clinical TB (n = 10), and analysed the genetic sequences of the IFN-gamma receptor 1 (IFN-gammaR1) and STAT1 genes in patients with disseminated TB (n = 18). IFN-gamma stimulated an increase in the expression of HLA-DR and CD64 on monocytes of both controls and patients; the rate of increase in expression was the same in both groups. Treatment with IFN-gamma before lipopolysaccharide (LPS) stimulation further increased tumour necrosis factor-alpha (TNF-alpha) production as compared to TNF-alpha production with LPS stimulation alone; the rate of increase in TNF-alpha production was the same in both groups. The known mutations in the coding sequences of the IFN-gammaR1 and STAT1 genes were not found in the patients with disseminated tuberculosis.

CONCLUSION

These results suggest that impairment of the IFN-gamma signalling pathway did not account for cases of clinical TB in this study.

Antinociception of intrathecal cholinesterase inhibitors and cholinergic receptors in rats

BACKGROUND

Intrathecal cholinesterase inhibitors have been shown to have an antinociceptive effect which is mediated through the spinal cholinergic receptors, mainly muscarinic receptor. Spinal nicotinic receptor also has been involved in the control of nociception. Authors characterized the respective role of muscarinic or nicotinic receptor for the antinociception of cholinesterase inhibitors and further determined the antinociceptive potency of them.

METHODS

Rats were prepared with intrathecal catheters. Formalin-induced flinching response was regarded as a nociceptive behavior.

RESULTS

Intrathecal neostigmine, physostigmine and edrophonium produced a dose-dependent suppression of flinching in both phases. Atropine and the M1 selective antagonist attenuated the effect of them, while the M2 selective antagonist did not affect. M3, M4 selective, and nicotinic receptor antagonists reversed the antinociception induced by edrophonium, but by neither neostigmine nor physostigmine. The ordering of potency was neostigmine > physostigmine > > edrophonium.

CONCLUSION

These data indicate that the nicotinic receptor may be involved, at least in part, in the antinociceptive action of cholinesterase inhibitor at the spinal level, and M1 receptor subtype may be a common pharmacologic site of action. Moreover, neostigmine is more potent than physostigmine and edrophonium.

Effects of intracoronary calcium chloride on regional oxygen balance and mechanical function in normal and stunned myocardium in dogs

BACKGROUND

Brief myocardial ischaemia has been demonstrated to result in mechanical and coronary endothelial dysfunction, in which calcium may play a role. We examined whether the mechanical and vascular responses to calcium are altered in postischaemic, reperfused myocardium.

METHODS

Regional myocardial oxygen consumption (MVO2), mechanical function and coronary blood flow (CBF) in response to calcium chloride (0.10, 0.25, 0.50 and 0.75 mg ml(-1) of CBF) directly infused into the left anterior descending (LAD) artery were determined before (normal) and 30 min after a 15-min-period of LAD occlusion (stunned) in an open-chest canine model. Percentage segment shortening (%SS) and percentage postsystolic shortening (%PSS) in the LAD territory were determined using ultrasonic crystals and CBF using a Doppler transducer. Myocardial extraction of oxygen (EO2) and lactate (Elac) was calculated.

RESULTS

The infusion of calcium chloride resulted in dose-dependent increases in %SS and MVO2 but did not affect %PSS in normal myocardium. These changes were accompanied by parallel increases in CBF, resulting in no change in EO2. In stunned myocardium, the responses to calcium chloride were not significantly altered, with the exception of a reduction in %PSS. However, ischaemia and reperfusion itself significantly reduced %SS and Elac and increased %PSS.

CONCLUSIONS

These data suggest that calcium chloride improves regional systolic and diastolic function both in normal and stunned myocardium. Calcium chloride is unlikely to cause direct coronary vasoconstriction or to deteriorate regional mechanical function in postischaemic myocardium.

Activation of caspase-8 in 3-deazaadenosine-induced apoptosis of U-937 cells occurs downstream of caspase-3 and caspase-9 without Fas receptor-ligand interaction

3-Deazaadenosine (DZA), a cellular methylation blocker was reported to induce the caspase-3-like activities-dependent apoptosis in U-937 cells. In this study, we analyzed the activation pathway of the caspase cascade involved in the DZA-induced apoptosis using specific inhibitors of caspases. In the U-937 cells treated with DZA, cytochrome c release from mitochondria and subsequent activation of caspase-9, -8 and -3 were observed before the induction of apoptosis. zDEVD-Fmk, a specific inhibitor of caspase-3, and zLEHD-Fmk, a specific inhibitor of caspase-9, prevented the activation of caspase-8 but neither caspase-3 nor caspase-9, indicating that caspase-8 is downstream of both caspase-3 and caspase-9, which are activated by independent pathways. zVAD-Fmk, a universal inhibitor of caspases, kept the caspase-3 from being activated but not caspase-9. Moreover, ZB4, an antagonistic Fas-antibody, exerted no effect on the activation of caspase-8 and induction of apoptosis by DZA. In addition, zVAD-Fmk and mitochondrial permeability transition pore (MPTP) inhibitors such as cyclosporin A (CsA) and bongkrekic acid (BA) did not block the release of cytochrome c from mitochondria. Taken together, these results suggest that in the DZA-induced apoptosis, caspase-8 may serve as an executioner caspase and be activated downstream of both caspase-3 and caspase-9, independently of Fas receptor-ligand interaction. And caspase-3 seems to be activated by other caspses including IETDase-like enzyme and caspse-9 seems to be activated by cytochrome c released from mitochondria without the involvement of caspases and CsA- and BA- inhibitory MPTP.

G alpha(q/11) coupled to mammalian phospholipase C beta 3-like enzyme mediates the ginsenoside effect on Ca(2+)-activated Cl(-) current in the Xenopus oocyte

Recently we demonstrated that ginsenosides, the active ingredients of Panax ginseng, enhanced Ca(2+)-activated Cl(-) current in the Xenopus oocyte through a signal transduction mechanism involving the activation of pertussis toxin-insensitive G protein and phospholipase C (PLC). However, it has not yet been determined precisely which G protein subunit(s) and which PLC isoform(s) participate in the ginsenoside signaling. To provide answers to these questions, we investigated the changes in ginsenoside effect on the Cl(-) current after intraoocyte injections of the cRNAs coding various G protein subunits, a regulator of G protein signaling (RGS2), and G beta gamma-binding proteins. In addition, we examined which of mammalian PLC beta 1-3 antibodies injected into the oocyte inhibited the action of ginsenosides on the Cl(-) current. Injection of G alpha(q) or G alpha(11) cRNA increased the basal Cl(-) current recorded 48 h after, and it further prevented ginsenosides from enhancing the Cl(-) current, whereas G alpha(i2) and G alpha(oA) cRNA injection had no significant effect. The changes following G alpha(q) cRNA injection were prevented when G beta(1)gamma(2) and G alpha(q) subunits were co-expressed by simultaneous injection of the cRNAs coding these subunits. Injection of cRNA coding G alpha(q)Q209L, a constitutively active mutant that does not bind to G beta gamma, produced effects similar to those of G alpha(q) cRNA injection. The effects of G alpha(q)Q209L cRNA injection, however, were not prevented by co-injection of G beta(1)gamma(2) cRNA. Injection of the cRNA coding RGS2, which interacts most selectively with G alpha(q/11) among various identified RGS isoforms and stimulates the hydrolysis of GTP to GDP in active GTP-bound G alpha subunit, resulted in a severe attenuation of ginsenoside effect on the Cl(-) current. Finally, antibodies against PLC beta 3, but not -beta 1 and -beta 2, markedly attenuated the ginsenoside effect examined at 3-h postinjection. These results suggest that G alpha(q/11) coupled to mammalian PLC beta 3-like enzyme mediates ginsenoside effect on Ca(2+)-activated Cl(-) current in the Xenopus oocyte.

A novel class of highly potent, selective, and non-peptidic inhibitor of Ras farnesyltransferase (FTase)

Design, synthesis and structure-activity relationship of a class of aryl pyrroles as farnesyltransferase inhibitors are described. In vitro and in vivo evaluation of a panel of these inhibitors led to identification of 2 (LB42908) as a highly potent (IC(50)=0.9 nM against H-Ras and 2.4 nM against K-Ras) antitumor agent that is currently undergoing preclinical studies.

Modulation of N-type Ca2+ currents by A1-adenosine receptor activation in male rat pelvic ganglion neurons

Modulation of voltage-activated Ca2+ channels by adenosine was investigated in male rat major pelvic ganglion (MPG) neurons by using the whole-cell variant of the patch-clamp technique. Adenosine inhibited high voltage-activated (HVA) Ca2+ currents in a concentration-dependent manner with an EC50 of 313 nM and a maximal inhibition of 36%, respectively. Inhibition of HVA Ca2+ currents in adrenergic and cholinergic MPG neurons was similar. Adenosine did not modulate T-type Ca2+ channels present in adrenergic MPG neurons. Reverse transcription-polymerase chain reaction analysis indicated that MPG neurons express mRNAs encoding A1 and A2a receptors. Ca2+ current inhibition by adenosine was mimicked by N6-cyclopentyladenosine, an A1-selective agonist (EC50 = 63 nM) and prevented by 100 nM 8-cyclopentyl-1,3-dipropylxanthine, an A1-selective antagonist. Conversely, CGS 21680, an A2a-selective agonist, displayed a relatively low potency (EC50 = 2200 nM) for inhibiting Ca2+ currents. The action of adenosine was significantly attenuated by 2 mM guanosine-5'-thiodiphosphate or 500 ng/ml pertussis toxin. The voltage dependence of adenosine-induced current inhibition was evident by 1) a bell-shaped profile between the current inhibition and test potentials, 2) kinetic slowing in the presence of agonist, and 3) relief of the current inhibition by a conditioning prepulse to +80 mV. Finally, 1 microM omega-conotoxin GVIA occluded adenosine-induced current inhibition. Taken together, we concluded that adenosine inhibits N-type Ca2+ currents by activation of A1 receptors via a voltage-dependent and PTX-sensitive pathway in rat MPG neurons. Our data may explain how adenosine acts as an inhibitory modulator of ganglionic and neuromuscular transmission in the pelvic plexus.

Cell-specific expression and subcellular localization of neurophysin-CAT-fusion proteins expressed from oxytocin and vasopressin gene promoter-driven constructs in transgenic mice

The cell-specific expression of both the oxytocin (OT) and vasopressin (VP) genes in magnocellular neurons (MCNs) of the hypothalamus has been proposed to be under the control of cis-elements in an intergenic region downstream of the VP gene. We examined this hypothesis using transgenic mice containing mouse genomic DNA-derived constructs linked to chloramphenicol acetyltransferase (CAT) reporters. VP gene expression was studied using constructs containing 3.8 kbp of the 5' flanking region and all the exons and introns in the mouse VP gene, which was fused at the end of exon 3 to a CAT reporter. The two VP-transgene constructs differed by the lengths of their VP gene 3' flanking regions (2.1 versus 3.6 kbp). A similar construct for the oxytocin CAT transgene was used which contained the full-length (3.6 kbp) downstream intergenic region between the mouse genes. All three transgenic constructs produced cell-specific expression of the CAT-reporter in the magnocellular neurons as determined by CAT-immunoreactivity. Oxytocin transgene expression was restricted to OT cells in two founders, and the two VP transgenes to VP cells in five founders. Electron microscopic immunocytochemistry showed that the CAT fusion proteins produced from the OT- and VP-transgenes were efficiently trafficked through the regulated secretory pathways in their respective magnocellular neurons, packaged into large dense core vesicles, and transported to nerve terminals in the posterior pituitary.

Micellar effect on the photolysis of hydrogen peroxide

Photolysis experiments were performed to quantify the effect of three anionic surfactants on the photolysis of hydrogen peroxide (H2O2) at the ambient laboratory temperature of 22+/-1 degrees C. H2O2 photolysis in water, methanol, and surfactant monomeric solution was also conducted to compare the photochemical reactivity of H2O2 in different media. Photolysis rates were highest for water, followed by micellar solutions, and lowest for methanol. The results show that the photochemical reactivity of H2O2 is less favorable in organic solvent than in water and surfactant micelles affect H2O2 photolysis. Retarded photolysis of H2O2 in micellar solutions implies that a fraction of H2O2 dissolved in water partitions into micellar pseudophase of surfactant. H2O2 partitioned into micelles has less photochemical reactivity and thus photolysis rate was retarded in the presence of micelles. Photolysis inhibitory level by micelles was shown to be dependent on the kinds of surfactants used in this study. In addition, the inhibitory effect by surfactant monomers was negligible due to the absence of micelles.

Differential regulation of G protein-gated inwardly rectifying K(+) channel kinetics by distinct domains of RGS8

1. The contribution of endogenous regulators of G protein signalling (RGS) proteins to G protein modulated inwardly rectifying K(+) channel (GIRK) activation/deactivation was examined by expressing mutants of Galpha(oA) insensitive to both pertussis toxin (PTX) and RGS proteins in rat sympathetic neurons. 2. GIRK channel modulation was reconstituted in PTX-treated rat sympathetic neurons following heterologous expression of G protein subunits. Under these conditions, noradrenaline-evoked GIRK channel currents displayed: (1) a prominent lag phase preceding activation, (2) retarded activation and deactivation kinetics, and (3) a lack of acute desensitization. 3. Unexpectedly, heterologous expression of RGS8 in neurons expressing PTX-i-RGS-insensitive Galpha(oA) shortened the lag phase and restored rapid activation, but retarded the deactivation phase further. These effects were found to arise from the N-terminus, but not the core domain, of RGS8 thus suggesting actions on channel modulation independently of GTPase acceleration. 4. These findings indicate that different domains of RGS8 make distinct contributions to the temporal regulation of GIRK channels. The RGS8 core domain accelerates termination of the G-protein cycle presumably by increasing Galpha GTPase activity. In contrast, the N-terminal domain of RGS8 appears to promote entry into the G protein cycle, possibly by enhancing coupling of receptors to the G protein heterotrimer. Together, these opposing effects should allow for an increase in temporal fidelity without a dramatic decrease in signal strength.

Synthesis of a polymerizable metal-ion-chelating lipid for fluid bilayers

Hydrated lipid structures, such as liposomes, that display tethered metal-ion-chelating groups have proven useful in peptide and protein binding, as well as 2D protein crystallization through molecular recognition of accessible histidine sites in proteins and peptides. Polymerizable metal-ion-chelating lipids bearing a reactive diacetylene group have been described. These interesting compounds can be polymerized in the solid-analogous phase. Here we describe the design of the first polymerizable metal-ion-chelating lipid that can be used in the fluid, i.e., liquid analogous, phase of lipid bilayers. The synthesis of 1-palmitoyl-2-[8-[(E,E)-2',4'-hexadienoyloxy]octanoyl]-sn-glycero-3-N-[11-[N',N'-bis[carboxymethyl]imino]-3,6,9-trioxaundecanoyl] phosphatidylethanolamine (1) is described. The chelator moiety, iminodiacetate (IDA), was linked to the polymerizable phosphatidylethanolamine (PE) with a terminal 2,4-hexadienoyl (sorbyl) group through an oligo(ethylene glycol)-based spacer. Lipid 1-Cu complex is designed to be combined with the corresponding polymerizable matrix lipids (bis-SorbPC) to form functionalized liposomes that can be stabilized by various polymerization methods.

The effects of opioids on isolated human pregnant uterine muscles

We determined the effects of fentanyl, sufentanil, morphine, and meperidine on the spontaneous contractility of isolated human pregnant uterine muscle strips. Uterine specimens were obtained from normal full-term parturients undergoing elective lower-segment cesarean delivery. Longitudinal muscle strips were prepared and mounted vertically in tissue chambers to record their isometric tension. Opioid concentration-response curves were constructed after rhythmic contractions were established. The responses were also examined in the presence of opioid receptor blocker, nitric oxide synthase inhibitor, beta-adrenoceptor blocker, or cyclooxygenase inhibitor. Fentanyl and meperidine inhibited uterine contractility in a concentration-dependent manner, their concentration that inhibited 50% being 2.3 x 10(-6) and 1.0 x 10(-3)M, respectively. Sufentanil and morphine had no significant effects on uterine contractility. Pretreatment with either naloxone, N(G)-nitro-L-arginine methyl ester, atenolol, or indomethacin did not affect the uterine responses to opioids. These results demonstrate that fentanyl and meperidine may have direct inhibitory effects on the contractility of the human uterus, though at supraclinical concentrations.

IMPLICATIONS

Opioids do not have a significant effect on spontaneous contractions of gravid human uterine muscle at their clinically relevant concentrations.

Induction of apoptosis in human leukemia cells by 3-deazaadenosine is mediated by caspase-3-like activity

3-Deazaadenosine (DZA), one of the potent inhibitors of S-adenosylhomocysteine hydrolase, is known to possess several biological properties including an induction of apoptosis. To evaluate a possibility that DZA may be utilized for the treatment of human leukemia, we studied molecular events of cell death induced by DZA in human leukemia HL-60 and U-937 cells. DZA induced a specific cleavage of poly ADP-ribose polymerase (PARP) and an activation of the cysteine protease caspase-3/CPP32 which is known to cleave PARP. DZA-mediated nuclear DNA-fragmentation was completely blocked in the presence of a universal inhibitor of caspases (z-VAD-fmk) or the specific inhibitor of caspase-3 (z-DEVD-fmk) unlike of cycloheximide (CHX). DNA fragmentation was preceded by the lowering of c-myc mRNA in the DZA treated cells. In addition, DZA-induced apoptosis was blocked by pretreatment with adenosine transporter inhibitors such as nitrobenzylthioinosine (NBTI) and dipyridamole (DPD). Taken together, these results demonstrate that DZA-induced apoptosis initiated through an active transport of DZA into human leukemia cells, is dependent on the caspase-3-like activity without de novo synthesis of proteins and possibly involves c-myc down-regulation.

Evidence that ginsenosides prevent the development of opioid tolerance at the central nervous system

The analgesic effect of ginsenosides or morphine was first determined following intrathecal (i.t.) administration in rat tail-flick test. The effect of chronic i.t. co-administration of ginsenosides with morphine on the development of opioid tolerance were also examined using rat tail-flick test. Administration of ginsenosides (i.t.) produced a weak antinociception in a dose-dependent manner. Administration of morphine (i.t.) also produced antinociception in a dose-dependent manner. The ED50 was 1.20 microg (1.14-1.29 microg). However, acute i.t. co-administration of ginsenosides with morphine was not additive in antinociception. Repeated i.t. co-administration of 200 microg ginsenosides with 10 microg morphine inhibited the development of tolerance induced by 10 microg morphine in rat tail-flick test, although i.t. co-administration of 50 or 100 microg ginsenosides with morphine was without effect. In conclusion, these results indicate that i.t. administered ginsenosides produce an antinociception in rat tail-flick test and also prevent opioid tolerance caused by chronic treatment with morphine at the spinal sites.

Endogenous regulator of G-protein signaling proteins modify N-type calcium channel modulation in rat sympathetic neurons

Experiments using heterologous overexpression indicate that regulator of G-protein signaling (RGS) proteins play important roles in Gbetagamma-mediated ion channel modulation. However, the roles subserved by endogenous RGS proteins have not been extensively examined because tools for functionally inhibiting natively expressed RGS proteins are lacking. To address this void, we used a strategy in which Galpha(oA) was rendered insensitive to pertussis toxin (PTX) and RGS proteins by site-directed mutagenesis. Either PTX-insensitive (PTX-i) or both PTX- and RGS-insensitive (PTX/RGS-i) mutants of Galpha(oA) were expressed along with Gbeta(1) and Ggamma(2) subunits in rat sympathetic neurons. After overnight treatment with PTX to suppress natively expressed Galpha subunits, voltage-dependent Ca(2+) current inhibition by norepinephrine (NE) (10 microm) was reconstituted in neurons expressing either PTX-i or PTX/RGS-i Galpha(oA). When compared with neurons expressing PTX-i Galpha(oA), the steady-state concentration-response relationships for NE-induced Ca(2+) current inhibition were shifted to lower concentrations in neurons expressing PTX/RGS-i Galpha(oA). In addition to an increase in agonist potency, the expression of PTX/RGS-i Galpha(oA) dramatically retarded the current recovery after agonist removal. Interestingly, the alteration in current recovery was accompanied by a slowing in the onset of current inhibition. Together, our data suggest that endogenous RGS proteins contribute to membrane-delimited Ca(2+) channel modulation by regulating agonist potency and kinetics of G-protein-mediated signaling in neuronal cells.

Direct block by bisindolylmaleimide of rat Kv1.5 expressed in Chinese hamster ovary cells

The interaction of bisindolylmaleimide (BIM), widely used as a specific protein kinase C (PKC) inhibitor, with rat brain Kv1.5 (rKv1.5) channels stably expressed in Chinese hamster ovary cells was investigated using the whole-cell patch-clamp technique. BIM (I) and its inactive analog, BIM (V), inhibited rKv1.5 currents at +50 mV in a reversible concentration-dependent manner with an apparent K(d) value of 0.38 and 1.70 microM, respectively. BIM (I) accelerated the decay rate of inactivation of rKv1.5 currents but did not significantly modify the kinetics of current activation. Other specific PKC inhibitors, chelerythrine and PKC 19-36, had no effect on rKv1.5 and did not prevent the inhibitory effect of BIM (I). The inhibition of rKv1.5 by BIM (I) and BIM (V) was highly voltage-dependent between -30 and 0 mV (voltage range of channel opening), suggesting that both drugs interact preferentially with the open state of the channel. The additional inhibition by BIM (I) displayed a voltage dependence (delta = 0.19) in the full activation voltage range positive to 0 mV, but was not shown in BIM (V) (delta = 0). The rate constants of association and dissociation for BIM (I) were 9.63 microM(-1) s(-1) and 5.82 s(-1), respectively. BIM (I) increased the time constant of deactivation of tail currents from 26. 35 to 45.79 ms, resulting in tail crossover phenomenon. BIM (I) had no effect on the voltage dependence of steady-state inactivation. BIM (I) produced use-dependent inhibition of rKv1.5, which was consistent with the slow recovery from inactivation in the presence of drug. These results suggest that BIM (I) directly inhibits rKv1.5 channels in a phosphorylation-independent, and state-, voltage-, time-, and use-dependent manner.

Effect of G protein heterotrimer composition on coupling of neurotransmitter receptors to N-type Ca(2+) channel modulation in sympathetic neurons

Voltage-dependent (VD) inhibition of N-type Ca(2+) channels is mediated primarily by neurotransmitter receptors that couple to pertussis toxin (PTX)-sensitive G proteins (such as G(o) and G(i)). To date, however, the composition of heterotrimeric complexes, i.e., specific Galphabetagamma combinations, capable of coupling receptors to N-type Ca(2+) channels has not been defined. We addressed this question by heterologously expressing identified Galphabetagamma combinations in PTX-treated rat sympathetic neurons and testing for reconstitution of agonist-mediated VD inhibition. The heterologously expressed Galpha subunits were rendered PTX-insensitive by mutating the codon specifying the ADP ribosylation site. The following results were obtained from this approach. (i) Expression of Galpha(oA), Galpha(oB), and Galpha(i2) (along with Gbeta(1)gamma(2)) reconstituted VD inhibition mediated by alpha(2)-adrenergic, adenosine, somatostatin, and prostaglandin E(2) receptors. Conversely, expression of Galpha(i1) and Galpha(i3) was ineffective at restoring coupling. (ii) Coupling efficiency, as determined from the magnitude of reconstituted Ca(2+) current inhibition, depended on both the receptor and Galpha subtype. The following rank order of coupling efficiency was observed: Galpha(oA) = Galpha(oB) > Galpha(i2) for alpha(2)-adrenergic receptor; Galpha(i2) > Galpha(oA) = Galpha(oB) for adenosine and prostaglandin E(2) receptors; and Galpha(oB) = Galpha(i2) > Galpha(oA) for the somatostatin receptor. (iii) In general, varying the Gbetagamma composition of Galpha(oA)-containing heterotrimers had little effect on the coupling of alpha(2)-adrenergic receptors to the VD pathway. Taken together, these results suggest that multiple, diverse Galphabetagamma combinations are capable of coupling neurotransmitter receptors to VD inhibition of N-type Ca(2+) channels. Thus, if exquisite Galphabetagamma-coupling specificity exists in situ, it cannot arise solely from the inherent inability of other Galphabetagamma combinations to form functional signaling complexes.

Prognostic factors in anterior temporal lobe resections for mesial temporal lobe epilepsy: multivariate analysis

PURPOSE

Even though there have been several studies on the prognostic factors of temporal lobe epilepsy (TLE) after lobectomy, no studies have been performed for homogeneous mesial TLE. Furthermore, most studies on the predictors of outcome of epileptic surgery were based on univariate analyses and did not consider modern epileptic surgery investigation modalities such as brain magnetic resonance imaging (MRI) and positron emission tomography (PET). We attempted to identify the prognostic factors in anterior temporal lobectomy (ATL) for mesial TLE with multivariate analysis.

METHODS

Ninety-three patients with mesial TLE (54 men and 39 women, mean age at surgery, 28.3 +/- 8.2 years) were included in the study. The primary outcome variable was the status of patients in the second postoperative year, classified as either seizure free (except aura), or not seizure free. Clinical, electroencephalographic, MRI, PET, Wada test, and pathological data were considered.

RESULTS

Seventy-eight (84.0%) patients had remission of seizures. With univariate analysis, age at surgery (p < 0.001), epilepsy duration before surgery (p = 0.04), and ipsilateral hippocampal sclerosis on MRI (p = 0.02) were found to be significant. By using multivariate analysis, age at surgery (p = 0.001) and ipsilateral hippocampal sclerosis on MRI (p = 0.03) were found to be the most significant prognostic factors.

CONCLUSIONS

Age at surgery and hippocampal sclerosis are independent prognostic factors for ATL in mesial TLE. These findings suggest that mesial TLE may be a progressive disorder, and surgical outcome is better when early ATL is performed.

Heterologous expression of a green fluorescent protein-pertussis toxin S1 subunit fusion construct disrupts calcium channel modulation in rat superior cervical ganglion neurons

The fusion construct pEGFP-PTXS1 was assembled by ligating cDNA encoding the S1 subunit of Bordetella pertussis toxin (PTX) into the plasmid pEGFP-C1 (which codes for enhanced green fluorescent protein). Microinjection of pEGFP-PTXS1 (1-100 ng/microl) into the nucleus of dissociated rat sympathetic ganglion neurons resulted in functional expression as determined from the diffuse green fluorescence and disruption of norepinephrine-mediated N-type Ca2+ channel modulation. The heterologously expressed toxin retained specificity for G alpha(i/o)-dependent pathways as VIP-mediated modulation of N-type Ca2+ channels and muscarine-mediated inhibition of M-type K+ channels persisted in pEGFP-PTXS1 expressing neurons. These data demonstrate that the S1 subunit of PTX is readily expressed in mammalian neurons and remains functional following fusion to the C-terminus of another protein.

3-deazaadenosine, a S-adenosylhomocysteine hydrolase inhibitor, has dual effects on NF-kappaB regulation. Inhibition of NF-kappaB transcriptional activity and promotion of IkappaBalpha degradation

Previously we reported that 3-deazaadenosine (DZA), a potent inhibitor and substrate for S-adenosylhomocysteine hydrolase inhibits bacterial lipopolysaccharide-induced transcription of tumor necrosis factor-alpha and interleukin-1beta in mouse macrophage RAW 264.7 cells. In this study, we demonstrate the effects of DZA on nuclear factor-kappaB (NF-kappaB) regulation. DZA inhibits the transcriptional activity of NF-kappaB through the hindrance of p65 (Rel-A) phosphorylation without reduction of its nuclear translocation and DNA binding activity. The inhibitory effect of DZA on NF-kappaB transcriptional activity is potentiated by the addition of homocysteine. Taken together, DZA promotes the proteolytic degradation of IkappaBalpha, but not IkappaBbeta, resulting in an increase of DNA binding activity of NF-kappaB in the nucleus in the absence of its transcriptional activity in RAW 264.7 cells. The reduction of IkappaBalpha by DZA is neither involved in IkappaB kinase complex activation nor modulated by the addition of homocysteine. This study strongly suggests that DZA may be a potent drug for the treatment of diseases in which NF-kappaB plays a central pathogenic role, as well as a useful tool for studying the regulation and physiological functions of NF-kappaB.

Sequestration of G-protein beta gamma subunits by different G-protein alpha subunits blocks voltage-dependent modulation of Ca2+ channels in rat sympathetic neurons

The membrane-delimited and voltage-dependent inhibition of N-type Ca2+ channels is mediated by Gbeta gamma subunits. Previously, exogenous excess GDP-bound GalphaoA has been shown to dramatically attenuate the norepinephrine (NE)-mediated Ca2+ current inhibition by sequestration of Gbeta gamma subunits in rat superior cervical ganglion (SCG) neurons. In the present study, we determined whether the attenuation of NE-mediated modulation is specific to GalphaoA or shared by a number of closely related (Galphatr, GalphaoB, Galphai1, Galphai2, Galphai3, Galphaz) or unrelated (Galphas, Galphaq, Galpha11, Galpha16, Galpha12, Galpha13) Galpha subunits. Individual Galpha subunits from different subfamilies were transiently overexpressed in SCG neurons by intranuclear injection of mammalian expression vectors encoding the desired protein. Strikingly, all Galpha subunits except Galphaz nearly blocked basal facilitation and NE-mediated modulation. Likewise, VIP-mediated Ca2+ current inhibition, which is mediated by cholera toxin-sensitive G-protein, was also completely suppressed by a number of Galpha subunits overexpressed in neurons. Galphas expression produced either enhancement or attenuation of the VIP-mediated modulation-an effect that seemed to depend on the expression level. The onset of the nonhydrolyzable GTP analog, guanylylimidodiphosphate-mediated facilitation was significantly delayed by overexpression of different GDP-bound Galpha subunits. Taken together, these data suggest that a wide variety of Galpha subunits are capable of forming heterotrimers with endogenous Gbeta gamma subunits mediating voltage-dependent Ca2+ channel inhibition. In conclusion, coupling specificity in signal transduction is unlikely to arise as a result of restricted Galpha/Gbeta gamma interaction.

Activation of various G-protein coupled receptors modulates Ca2+ channel currents via PTX-sensitive and voltage-dependent pathways in rat intracardiac neurons

In the present study, we examined the ability of several putative neurotransmitters and neuromodulators to modulate voltage-dependent Ca2+ channel currents in adult rat intracardiac neurons. Of 17 compounds tested, acetylcholine (Ach), neuropeptide Y (NPY), norepinephrine (NE), and met-enkephalin (met-Enk) were effective modulators of the Ca2+ currents. The neurotransmitter-induced current inhibition was associated with slow activation kinetics and relief by a strong depolarizing prepulse. Overnight pretreatment of neurons with pertussis toxin (PTX, 500 ng/ml) significantly attenuated the neurotransmitter-induced current inhibition. Heterologous expression of transducin, a known chelator of G-protein betagamma subunits, almost completely abolished the neurotransmitter-induced current inhibition. Taken together, our data suggest that four different neurotransmitters inhibit the Ca2+ channel currents in adult rat intracardiac neurons via a pathway that is voltage-dependent, membrane-delimited, and utilizes betagamma subunits released from PTX-sensitive G-proteins. The Ca2+ channel inhibition by non-cholinergic neurotransmitters may play important roles in regulation of neuronal excitability and Ach release at synapses in intracardiac ganglia, thereby contributing to cholinergic control of cardiac functions.

Focal lesion in the splenium of the corpus callosum in epileptic patients: antiepileptic drug toxicity?

BACKGROUND AND PURPOSE

Discrete focal lesions in the splenium of the corpus callosum on MR images in epileptic patients have received little attention in the literature. Our purpose was to describe these lesions, which may be related to the toxicity of antiepileptic drugs (AEDs), and to discuss the possible mechanisms of their development.

METHODS

We examined six patients with epilepsy whose brain MR imaging findings showed a discrete focal nonhemorrhagic lesion in the splenium of the corpus callosum. The medical records and MR images were reviewed retrospectively with respect to the patients' clinical history, medication, and laboratory findings to determine the etiology of the lesion.

RESULTS

In all six patients MR imaging showed a focal lesion in the splenium of the corpus callosum, which was ovoid in shape and 15 to 19 mm in size. In the three patients who received contrast material, there was no enhancement of the lesion. Four of six patients had a history of medication with dilantin, in two of whom the level of serum dilantin was found to be elevated (22.3 micrograms/mL and 70.4 micrograms/mL, respectively). Vigabatrin was administered in three patients, one of whom took dilantin together with vigabatrin. In two patients, the focal lesion in the corpus callosum disappeared on follow-up MR images after withdrawal of dilantin and/or vigabatrin.

CONCLUSION

A discrete, focal, ovoid, nonhemorrhagic lesion in the splenium of the corpus callosum may be seen on brain MR images of patients with epilepsy. The lesion is considered to be reversible demyelination related to AEDs toxicity.

G protein alpha subunit G alpha z couples neurotransmitter receptors to ion channels in sympathetic neurons

The functional roles subserved by G(alpha)z, a G protein alpha subunit found predominantly in neuronal tissues, have remained largely undefined. Here, we report that G(alpha)z coupled neurotransmitter receptors to N-type Ca2+ channels when transiently overexpressed in rat sympathetic neurons. The G(alpha)z-mediated inhibition was voltage dependent and PTX insensitive. Recovery from G(alpha)z-mediated inhibition was extremely slow but accelerated by coexpression with RGS proteins. G(alpha)z selectively interacted with a subset of receptors that ordinarily couple to N-type Ca2+ channels via PTX-sensitive Go/i proteins. In addition, G(alpha)z rescued the activation of heterologously expressed GIRK channels in PTX-treated neurons. These results suggest that G(alpha)z is capable of coupling receptors to ion channels and might underlie PTX-insensitive ion channel modulation observed in neurons under physiological and pathological conditions.

Granulocyte macrophage colony-stimulating factor is the main cytokine enhancing survival of eosinophils in asthmatic airways

Interleukin (IL)-3, IL-5 and granulocyte macrophage colony-stimulating factor (GM-CSF) prolong the survival of eosinophils, which are conspicuous in asthmatic airways, but it is still controversial which one plays a major role in enhancing the survival of eosinophils in asthmatic airways. The role of these cytokines in airway eosinophilia was investigated using bronchoalveolar lavage (BAL) fluids from 11 symptomatic and nine asymptomatic patients with asthma and eight normal subjects. Eosinophil survival-enhancing activity (ESEA) was measured by a numerical change in viable eosinophils isolated from the peripheral blood of atopic patients and cultured with BAL fluids. ESEA was characterized by neutralization with antibodies to IL-3, IL-5 and/or GM-CSF. The differential count of BAL cells was achieved using Diff-Quik stain. T-cell subsets and activated T-cells were analysed by flow cytometry with dual stain using monoclonal antibodies to CD3, CD4, CD8 and CD25. ESEA was detected in eight of 11 BAL fluids of symptomatic asthma, but not in those of normal controls or asymptomatic asthmatics. In six symptomatic asthmatics, the mean percentage of inhibition in ESEA by anti-GM-CSF was higher than that of anti-IL-5 as well as anti-IL-3 (p<0.05). A mixture of antibodies to IL-3, IL-5 and GM-CSF totally inhibited the ESEA in four cases. The ESEA correlated with the percentage of eosinophils (p<0.05) and that of CD25(+)CD4 lymphocytes (p<0.05) of BAL cells. In conclusion, granulocyte macrophage colony-stimulating factor, rather than interleukin-3 or -5, is associated with eosinophil survival-enhancing activity inside the airways of symptomatic asthmatics. The activation of CD4 lymphocytes is related to the elevation of such activity.

The T cell receptor subsets of lymphocytes in bronchoalveolar lavage in patients with active pulmonary tuberculosis

STUDY OBJECTIVE

To determine whether or not the levels of gamma/delta lymphocytes increase in bronchoalveolar lavage (BAL) fluid from patients with pulmonary tuberculosis.

DESIGN

Prospective data collection relating to cells in BAL fluid and peripheral blood mononuclear cells (PBMC) from patients with pulmonary tuberculosis and control subjects.

SETTING

A university hospital, from March 1990 to December 1993.

PATIENTS

Thirteen patients with pulmonary tuberculosis who were diagnosed by culture of Mycobacterium tuberculosis from their sputum of BAL fluid and/or clinical response were enrolled in the study. Fifteen healthy volunteers participated as control subjects.

MEASUREMENTS AND RESULTS

The differential cell counts in BAL fluid were made by Diff-Quik stain. The percentages of T-cell receptor (TCR) (gamma/delta and alpha/beta)-positive lymphocytes and interleukin 2 (IL-2) receptor-positive CD3 lymphocytes in BAL fluid and peripheral blood were measured by dual scan with flow-cytometry. The percentage and absolute number of lymphocytes and the percentages of CD3+, IL2R+ lymphocytes in BAL fluid significantly increased in patients with tuberculosis when compared with those of control subjects. The percentages and numbers of gamma/delta and alpha/beta TCR-positive lymphocytes in BAL fluid and PBMC from patients with tuberculosis and indistinguishable from those of control subjects.

CONCLUSIONS

gamma/delta Lymphocytes do not appear to have as much meaning in patients as they do in animal studies.

Muscarinic receptor activation modulates Ca2+ channels in rat intracardiac neurons via a PTX- and voltage-sensitive pathway

With use of the whole cell patch-clamp technique, effects of the potent muscarinic agonist oxotremorine methiodide (oxo-M) on voltage-activated Ca2+ channel currents were investigated in acutely dissociated adult rat intracardiac neurons. In all tested neurons oxo-M reversibly inhibited the peak Ba2+ current. Inhibition of the peak Ba2+ current by oxo-M was associated with slowing of activation kinetics and was concentration dependent. The concentration of oxo-M necessary to produce a half-maximal inhibition of current and the maximal inhibition were 40.8 nM and 75.9%, respectively. Inhibitory effect of oxo-M was completely abolished by atropine. Among different muscarinic receptor antagonists, methoctramine (100 and 300 nM) significantly antagonized the current inhibition by oxo-M, with a negative logarithm of dissociation constant of 8.3 in adult rat intracardiac neurons. Internal dialysis of neurons with guanosine 5'-(thio)triphosphate (GTPgammaS, 0.5 mM) could mimic the muscarinic inhibition of the peak Ba2+ current and significantly occlude inhibitory effects of oxo-M. In addition, the internal dialysis of guanosine-5'-O-(2-thiodiphosphate) (GDPbetaS, 2 mM) also significantly reduced the muscarinic inhibition of the peak Ba2+ current by oxo-M. Inhibitory effects of oxo-M were significantly abolished by pertussis toxin (PTX, 200 and 400 ng/ml) but not by cholera toxin (400 ng/ml). Furthermore, the bath application of N-ethylmaleimide (50 microM) significantly reduced the inhibition of the peak Ba2+ current by oxo-M. The oxo-M shifted the activation curve derived from measurments of tail currents toward more positive potentials. A strong conditioning prepulse to +100 mV significantly relieved the muscarinic inhibition of peak Ba2+ currents by oxo-M and the GTPgammaS-induced current inhibition. In a series of experiments, changes in intracellular concentration of bis-(o-aminophenoxy)-N,N,N',N'-tetraacetic acid and protein kinase activities failed to mimic or occlude the current inhibition by oxo-M. The dihydropyridine antagonist nifedipine (10 microM) was not able to occlude any of the inhibitory effects of oxo-M, and oxo-M (3 microM) failed to reduce the slow tail currents induced by the L-type agonist methyl 2,5-dimethyl-4-[2-(phenylmethyl)benzoyl]-1H-pyrrole-3-carboxylate (FPL 64176; 2 microM). However, omega-conotoxin (omega-CgTX) GVIA (1 microM) significantly occluded the muscarinic inhibition of the Ba2+ currents. In the presence of omega-CgTX GVIA (1 microM) and nifedipine (10 microM), oxo-M could further inhibit approximately 20% of the total Ca2+ current. After complete removal of N-, Q-, and L-type currents with use of omega-CgTX GVIA, omega-agatoxin IVA, and nifedipine, 70% of the R-type current (approximately 6-7% of the total current) was inhibited by oxo-M (3 microM). In conclusion, the M2 muscarinic receptor activation selectively inhibits N-, Q-, and R-type Ca2+ channel currents, sparing L-type Ca2+ channel currents mainly via a PTX- and voltage-sensitive pathway in adult rat intracardiac neurons.

Calcium channel currents in acutely dissociated intracardiac neurons from adult rats

With the use of the whole cell patch-clamp technique, multiple subtypes of voltage-activated calcium channels, as indicated by measuring Ba2+ currents, were pharmacologically identified in acutely dissociated intracardiac neurons from adult rats. All tested neurons that were held at -80 mV displayed only high-voltage-activated (HVA) Ca2+ channel currents that were completely blocked by 100 microM CdCl2. The current density of HVA Ca2+ currents was dependent on the external Ca2+ concentration. The Ba2+ (5 mM) currents were half-activated at -16.3 mV with a slope of 5.6 mV per e-fold change. The steady-state inactivation was also voltage dependent with half-inactivation at -33.7 mV and a slope of -12.1 mV per e-fold change. The most effective L-type channel activator, FPL 64176 (2 microM), enhanced the Ba2+ current in a voltage-dependent manner. When cells were held at -80 mV, the saturating concentration (10 microM) of nifedipine blocked approximately 11% of the control Ba2+ current. The major component of the Ca2+ channels was N type (63%), which was blocked by a saturating concentration (1 microM) of omega-conotoxin GVIA. Approximately 19% of the control Ba2+ current was sensitive to omega-conotoxin MVIIC (5 microM) but insensitive to low concentrations (30 and 100 nM) of omega-agatoxin IVA (omega-Aga IVA). In addition, a high concentration (1 microM) of omega-Aga IVA occluded the effect of omega-conotoxin MVIIC. Taken together, these results indicate that the omega-conotoxin MVIIC-sensitive current represents only the Q type of Ca2+ channels. The current that was insensitive to nifedipine and various toxins represents the R-type current (7%), which was sensitive to 100 microM NiCl2. In conclusion, the intracardiac neurons from adult rats express at least four different subtypes (L, N, Q, and R) of HVA Ca2+ channels. This information is essential for understanding the regulation of synaptic transmission and excitability of intracardiac neurons by different neurotransmitters and neural regulation of cardiac functions.

A case of bronchiolitis obliterans organizing pneumonia associated with adenovirus

A 58-year-old man described a short history of dyspnea and a preceding flu like illness with roentgenographic features of an interstitial lung disease. An open lung biopsy specimen from him showed bronchiolitis obliterans with organizing pneumonia (BOOP). Adenovirus was isolated from a throat swab. There was both clinical and radiographic improvement with supportive care. We herein report a first case of BOOP associated with adenovirus in Korea.

A systematic survey of the intergenic region between the murine oxytocin- and vasopressin-encoding genes

The genomic region between the oxytocin (OT) and vasopressin (VP) genes in the two strains of mice was independently sequenced by our two groups. In this report, we present our collated sequence data and analyses. The mouse intergenic region (MUIGR) was aligned to that of the rat, which has been reported to contain 6.4-kb long interspersed nuclear element (LINE). The MUIGR sequences in the two mice strains did not contain any LINE sequences. This suggests that the approximately 3.5-kb sequence that is conserved between the rat and mouse intergenic regions is likely to be involved in the regulation of OT and VP expression. We also observed several conserved putative transcription factor recognition sequences. Analysis of the MUIGR revealed the lack of any significant ORFs, but the presence of several repetitive elements.

The yeast transcription terminator for RNA polymerase I is designed to prevent polymerase slippage

A transcription terminator for RNA polymerase I (polI) in the yeast, Saccharomyces cerevisiae, is composed of two essential elements, the 11bp binding site for Reb1p and an upstream T-rich element coding for the last 10-12 nucleotides of the terminated transcript. We now show that, if the upstream element is changed to homopolymer T residues, polI undergoes iterative slippage, long poly(U) tails are added to the transcript, and termination is impaired. Reinsertion of one or two non-T residues within a critical region prevents iterative slippage and reinstates termination. A survey of naturally occurring terminators reveals that many contain T-rich upstream regions with non-T residues situated appropriately to prevent slippage. We discuss the possibility that the first step in slippage, backward sliding of both the transcript and the catalytic center of the polymerase, may be an obligatory step in the normal termination process.

Clinical features of interstitial lung diseases

OBJECTIVES

Interstitial lung diseases (ILD) are heterogeneous groups of disorders that involve the interstitium of the lung. Lung biopsy is mandatory in most cases of ILD for diagnosis. In Korea, a few clinical data about ILD were analyzed on the basis of pathologic proof. Thus, we analysed the clinical profiles of patients with ILD who had lung biopsy in a tertiary university hospital.

METHODS

Clinical and pathologic data concerning 100 patients who had open lung biopsy (OLB) and/or transbronchial lung biopsy (TBLB) were prospectively analysed. Two patients were excluded because one patient was proven to have metastatic cancer and the other to have miliary tuberculosis. One patient had two combined diseases: rheumatoid arthritis and pneumoconiosis. Thus, 99 cases were analysed from 98 patients. Demographic characteristics, pulmonary functions and pathologic findings were analysed according to the disease entities of ILD. Pathologic findings were classified only in patients who had OLB. Clinical courses were also analysed during follow-up.

RESULTS

OLB was performed on 68 cases with concomittant TBLB in 18 cases and 30 cases had TBLB only. Mediastinal lymph node biopsy has performed on one case. The most common cause of ILD was IPF (51.5%), which was followed by CVD.PF (15.2%) and HP (9.1%). Average age of 51 cases with idiopathic pulmonary fibrosis (IPF) was 60 +/- 11 years, that of 15 cases with collagen vascular disease associated pulmonary fibrosis (CVD-PF) was 46 +/- 17 years and that of 9 cases with hypersensitivity pneumonitis (HP) was 53 +/- 8.1 years. In IPF, CVD-PF AND HP, male to female ratio was equal. But female was dominant in sarcoidosis and male was dominant in pneumoconiosis. Pulmonary function tests (PFT) in IPF, CVD-PF and HP were restrictive patterns in half of the cases. In pneumoconiosis and sarcoidosis, PFT showed normal pattern. Usual interstitial pneumonia (UIP) was the most common pathologic type in IPF and CVD-PF. The most common cause of CVD-PF was rheumatoid arthritis. The overall mortality rate was 12.1%.

CONCLUSION

We reported that the ILD had a variety of disease entities and pathologic types even in one tertiary referral hospital. We hope that a multi-center study will be performed on the basis of pathologic proof in the future.

Interleukin-4 and low-affinity receptor for IgE on B cells in peripheral blood of patients with atopic bronchial asthma

BACKGROUND

A greater frequency of type 2 helper cells producing IL-4 without interferon-gamma is thought to be responsible for the elevated IgE in serum of atopic subjects. However, the proportion of B cells responding to IL-4 by an increased synthesis of IgE is also higher in atopic subjects than in nonatopic subjects.

OBJECTIVE

Important questions are whether the elevated IgE in atopic subjects is due to overproduction of IL-4 by T cells, the enhanced sensitivity of B cells to IL-4, or both and whether functional alterations of T and B cells are related to the development of allergic diseases.

METHODS

Spontaneous and IL-4-induced CD23 expression on B cells was examined to evaluate the response of B cells to IL-4, and production of IL-4 by concanavalin-A-stimulated peripheral blood mononuclear cells (PBMCs) was measured to evaluate the T-cell function in nonatopic normal subjects, atopic normal subjects, and patients with symptomatic bronchial asthma.

RESULTS

IL-4-induced expression of CD23 on B cells was greater in normal atopic subjects and atopic patients with bronchial asthma than in normal nonatopic subjects. IL-4 generated by concanavalin A-stimulated PBMCs was also higher in normal atopic subjects and atopic patients with bronchial asthma than in normal non-atopic subjects. The expression of CD23 on B cells and IL-4 generation by concanavalin-A-stimulated PBMCs were not different between normal atopic subjects and atopic patients with bronchial asthma.

CONCLUSIONS

Both B-cell and T-cell functions are enhanced in atopic subjects. However, neither enhanced B-cell nor T-cell function is a hallmark in development of allergic diseases.

Effects of adenosine tetraphosphate (ATPP) on vascular tone in the isolated rat aorta

Effects of a platelet-released, naturally occurring nucleotide, adenosine 5'-tetraphosphate (ATPP) on vascular tone were analyzed in the isolated rat aorta. Under resting tension ATPP (1 approximately 100 microM) elicited concentration-dependent contractions in endothelium-intact aortic rings in contrast to the concentration-dependent relaxation with ATP. In endothelium-denuded aortic rings, ATPP induced contraction, as ATP did, but with a greater potency. alpha, beta-methylene ATP (APCPP 50 microM), a P2x-purinoceptor antagonist, significantly inhibited ATPP- as well as ATP-induced contractions in the endothelium-denuded preparations suggesting that ATPP acts via P2x-purinoceptors. ATPP (10 approximately 100 microM) relaxed precontracted aortic rings with an intact endothelium in a concentration-dependent manner. This effect of ATPP was 3.7 fold less potent than that of ATP. However, after P2x-purinoceptor blockade, the effect became identical between the two nucleotides. Reactive blue 2, a selective antagonist of P2x-purinoceptors, significantly attenuated the ATPP-induced relaxation with no change in the ATP-induced relaxation. These results indicated that the rat aortic endothelium contains heterogeneous populations of P2-purinoceptors (possibly P2y and nucleotide receptors). Since ATPP shows dual effects depending upon the vascular tension, it may play a significant role in the physiological regulation of vascular tone.

The release element of the yeast polymerase I transcription terminator can function independently of Reb1p

The Saccharomyces cerevisiae polymerase I (polI) transcription terminator utilizes a DNA-binding protein (Reb1p) as part of a signal that causes the polymerase to pause prior to release from the template. To study the release element of the terminator, independent of the Reb1p pause signal, we have replaced the Reb1p binding site with the binding site for the lac repressor, which acts as a self-contained heterologous pause signal for polI. Release efficiency is maximal when the lac repressor causes polI to pause in exactly the same position that Reb1p would have caused it to pause, suggesting that polI must be precisely positioned for transcript release to occur. Mutational analysis shows that the release element is a region rich in T residues which codes for the extreme 3' end of the transcript and which has no apparent ability to form hairpins when transcribed into RNA. We discuss possible mechanisms whereby this polI release element might function.

A case of amiodarone-associated pulmonary toxicity

Amiodarone is an iodinated benzofuran derivative that represents a new and extremely effective therapy for certain life-threatening refractory cardiac arrgythmia. There are numerous side effects associated with amiodarone therapy, including corneal microdeposits. Skin reactions and others. Pulmonary toxicity, however, represents the most serious adverse reaction limiting the clinical effecacy of this antidysrhythmic drug. Recently, we experienced a case of amiodarone-induced pulmonary toxicity confirmed by open lung biopsy with light-and electron-microscopy. So, we report a case of amiodarone-induced pulmonary toxicity with a literature review.

Bronchial hyperreactivity in patients with endobronchial tuberculosis

Some patients with endobronchial tuberculosis (EBTB) have wheeze on physical examination and normal chest PA, which mimic bronchial asthma. Non-specific bronchial challenge tests have been used to confirm the presence of bronchial hyperreactivity, which is a hallmark of bronchial asthma. To evaluate the effect of endobronchial tuberculous inflammation on bronchial responsiveness to histamine, the provocation concentrations of histamine required to reduce FEV1 by 20% of the pre-challenge baseline (PC20) were compared between patients with EBTB, patients with symptomatic bronchial asthma and normal, healthy controls. PC20 in EBTB patients (17.2 +/- 2.3 mg ml-1) and normal controls (19.5 +/- 1.4 mg ml-1) were significantly higher than in bronchial asthma patients (0.99 +/- 0.15 mg ml-1). PC20 in EBTB patients was not affected by disease location in the bronchial tree was not correlated with FVC or FEV1. In conclusion, one should consider the possibility of EBTB for differential diagnosis from bronchial asthma, if airway responsiveness appears normal in wheezy patients.