Intracellular accumulation of mannopine, an opine produced by crown gall tumors, transiently inhibits growth of Agrobacterium tumefaciens

pYDH208, a cosmid clone from the octopine-mannityl opine-type tumor-inducing (Ti) plasmid pTi15955 confers utilization of mannopine (MOP) and agropine (AGR) on Agrobacterium tumefaciens strain NT1. NT1 harboring pYDH208 with an insertion mutation in mocC, which codes for MOP oxidoreductase, not only fails to utilize MOP as a sole carbon source, but also was inhibited in its growth by MOP and AGR. In contrast, the growth of mutants with insertions in other tested moc genes was not inhibited by either opine. Growth of strains NT1 or UIA5, a derivative of C58 that lacks pAtC58, was not inhibited by MOP, but growth of NT1 or UIA5 harboring pRE10, which codes for the MOP transport system, was inhibited by the opine. When a clone expressing mocC was introduced, the growth of strain NT1(pRE10) was not inhibited by MOP, although UIA5(pRE10) was still weakly inhibited. In strain NT1(pRE10, mocC), santhopine (SOP), produced by the oxidation of MOP by MocC, was further degraded by functions encoded by pAtC58. These results suggest that MOP and, to a lesser extent, SOP are inhibitory when accumulated intracellularly. The growth of NT1(pRE10), as measured by turbidity and viable cell counts, ceased upon the addition of MOP but restarted in a few hours. Regrowth was partly the result of the outgrowth of spontaneous MOP-resistant mutants and partly the adaptation of cells to MOP in the medium. Chrysopine, isochrysopine, and analogs of MOP in which the glutamine residue is substituted with other amino acids were barely taken up by NT1(pRE10) and were not inhibitory to growth of the strain. Sugar analogs of MOP were inhibitory, and those containing sugars in the D form were more inhibitory than those containing sugars in the L form. MOP analogs containing hexose sugars were more inhibitory than those containing sugars with three, four, or five carbon atoms. Mutants of NT1(pRE10) that are resistant to MOP arose in the zone of growth inhibition. Genetic and physiological analyses indicate that the mutations are located on pRE10 and abolish uptake of the opine.

Procedures for estimating confidence intervals for selected method performance parameters

Procedures for estimating confidence intervals (CIs) for the repeatability variance (sigmar2), reproducibility variance (sigmaR2 = sigmaL2 + sigmar2), laboratory component (sigmaL2), and their corresponding standard deviations sigmar, sigmaR, and sigmaL, respectively, are presented. In addition, CIs for the ratio of the repeatability component to the reproducibility variance (sigmar2/sigmaR2) and the ratio of the laboratory component to the reproducibility variance (sigmaL2/sigmaR2) are also presented.

Births of freemartins derived from embryos reconstructed with ear fibroblasts

Although the combination of artificial insemination (AI) and embryo transfer (ET) is effective for preventing large offspring syndrome in clone cattle production, it may cause freemartinism. In this study, 51 reconstructed embryos were transferred to artificially inseminated recipients. Of those 9 twin pregnancies, three delivered male and female offsprings. The females had tufts of long coarse hair and short blind pouch at the vaginal end. At necropsy, hypoplastic testicles and epididymis, which connected to the uterus through the spermatic cord, were found and seminal vesicles were also noted. All females had mixed sex chromosome configuration (60, XX and 60, XY). These results suggest that the combined ET program can cause freemartinism, which reduces the efficiency of clone cattle production.

Development of an ELISA for the detection of the residues of the insecticide imidacloprid in agricultural and environmental samples

A competitive enzyme-linked immunosorbent assay (ELISA) for the chloronicotinyl insecticide imidacloprid was developed using a polyclonal antibody produced against a hapten conjugated through the imidazolidine to keyhole limpet hemocyanin. In the standard curve of imidacloprid, an IC(50) of 17.3 ng/mL was obtained using a competitive heterologous system at pH 10. Very low cross-reactivity was found for some structurally related compounds including the insecticide thiacloprid. The high cross-reactivity with a metabolite containing the carbonyl group in the imidazolidine moiety suggests the involvement of its polarity and stereochemical fitness in forming the antibody--antigen complex. The effects of various assay conditions, including organic solvents, detergent content, salt concentration, and pH on the sensitivity were evaluated. High-performance liquid chromatography was run for comparison to validate the ELISA with fortified water samples, the correlation being 0.997-0.998 (n = 15) with a slope of 1.10--1.38. The ELISA turned out to be a convenient tool for monitoring imidacloprid residues in agricultural and environmental samples.

Possible roles of JNK pathway in the regulation of hippocampal proenkephalin and immediate early gene expression induced by kainic acid

Mitogen-activated protein kinases (MAPKs) may play crucial roles in the kainic acid (KA)-evoked excitotoxic effect and the regulation of transcription factors (e.g. c-Fos and c-Jun) in hippocampus, but their exact role in the regulation of KA-induced opioid peptides expression has not been well characterized in vivo. Therefore, we examined possible involvement of the phosphorylated form of JNK, as well as CREB, in the regulation of KA-induced proenkephalin and immediate early genes (IEGs) expression in the rat hippocampus. KA increased proenkephalin mRNA expression in rat hippocampus, which was decreased by pre-administration with cycloheximide (CHX, a protein synthesis inhibitor). KA alone increased c-fos as well as c-jun mRNA levels. CHX further enhanced KA-induced c-fos and c-jun mRNA levels. Additionally, KA increased the phosphorylation of JNK, especially JNK1, which was attenuated by CHX. CHX decreased KA-induced c-Fos protein expression. Interestingly, CHX itself increased the phosphorylation of CREB, which was abolished by KA administration. Our results suggest that the phosphorylation of JNK is involved in the up-regulation of the proenkephalin gene expression via c-Fos and c-Jun that is induced by KA in rat hippocampus. However, the phosphorylation of CREB is not associated with the up-regulation of the proenkephalin mRNA level induced by KA in the rat hippocampus.

Forskolin inhibits expression of inducible nitric oxide synthase mRNA via inhibiting the mitogen activated protein kinase in C6 cells

This study has demonstrated the mechanism of protein kinase A (PKA)-dependent inhibition of astrocytic nitric oxide production and inducible NO synthase mRNA expression induced by lipopolysaccharide. In C6 glioma cells, the stimulation with lipopolysaccharide (LPS; 1 microg/ml) evoked increases of nitric oxide (NO) production, NO synthase (iNOS) mRNA expression, phosphorylation of p38 mitogen activated protein kinase (p-p38), and the activation of NF kappa B. LPS-induced NO production and iNOS mRNA expression were inhibited by the pretreatment with forskolin (FSK; 5 microM) in a dose-dependent manner, and which were reversed by PKA inhibition by compound H89. Furthermore, LPS-induced increases of p-p38, but not activation of NF kappa B, were also reduced by FSK and H89 reversed the FSK-induced inhibition response. The dose-dependent inhibition of NO production and iNOS mRNA expression by compound SB203580 (p38 inhibitor) suggests the participation of p38 in PKA-dependent inhibition of LPS-induced NO production and iNOS mRNA expression. However, the activation of NF kappa B by LPS also not affected by SB203580. Therefore, our results suggest that, in C6 glioma cells, LPS-induced NO production and iNOS gene expression may be regulated by PKA pathway through the reduction of activity of p38 kinase. This inhibitory role of PKA may not involve the activation of NF kappa B.

Activity of descending contralateral movement detector neurons and collision avoidance behaviour in response to head-on visual stimuli in locusts

We recorded the activity of the right and left descending contralateral movement detectors responding to 10-cm (small) or 20-cm (large) computer-generated spheres approaching along different trajectories in the locust's frontal field of view. In separate experiments we examined the steering responses of tethered flying locusts to identical stimuli. The descending contralateral movement detectors were more sensitive to variations in target trajectory in the horizontal plane than in the vertical plane. Descending contralateral movement detector activity was related to target trajectory and to target size and was most sensitive to small objects converging on a direct collision course from above and to one side. Small objects failed to induce collision avoidance manoeuvres whereas large objects produced reliable collision avoidance responses. Large targets approaching along a converging trajectory produced steering responses that were either away from or toward the side of approach of the object, whereas targets approaching along trajectories that were offset from the locust's mid-longitudinal body axis primarily evoked responses away from the target. We detected no differences in the discharge properties of the descending contralateral movement detector pair that could account for the different collision avoidance behaviours evoked by varying the target size and trajectories. We suggest that descending contralateral movement detector properties are better suited to predator evasion than collision avoidance.

Increased erythritol production in fed-batch cultures of Torula sp. by controlling glucose concentration

The effect of glucose concentration on erythritol production by Torula sp. was investigated. The maximum volumetric productivity of erythritol was obtained at an initial glucose concentration of 300 g l(-1) in batch culture. The volumetric productivity was maximal at a controlled glucose concentration of 225 g l(-1), reducing the lag time of the erythritol production. A fed-batch culture was established with an initial glucose concentration of 300 g l(-1) and with a controlled glucose concentration of 225 g l(-1) in medium containing phytic acid as a phosphate source. In this fed-batch culture, a final erythritol production of 192 g l(-1) was obtained from 400 g l(-1) glucose in 88 h. This corresponded to a volumetric productivity of 2.26 g l(-1) h(-1) and a 48% yield.

I(f) current and spontaneous activity in mouse embryonic ventricular myocytes

Knowledge of the initiation of electrical and contractile activity in the embryonic heart relies to a large extent on data obtained in chicken. In recent years, molecular biological techniques have raised an interest in mouse physiology, including early embryonic development. We studied action potentials and the occurrence of one of the pacemaker currents, I(f), by the whole-cell voltage and current-clamp technique at the earliest stage at which a regular heartbeat is established (9.5 days postcoitum) and at 1 day before birth. We show, first, that at the early stage there is a prominent I(f) in mouse embryonic ventricles, which decreases by 82% before birth in concert with the loss of regular spontaneous activity of ventricular cells. Second, the decrease in I(f) current is associated with a slight change in channel gating kinetics and a decrease in total mRNA expression of the genes encoding for I(f) current. Third, the most prevalent mRNA subtype is switched from HCN4 to HCN2 during the second half of embryonic development. Fourth, the I(f) current may be modulated by the beta-adrenergic cascade, although the coupling to the beta-adrenoceptor in the sarcolemma itself is not yet mature. We conclude that I(f) current of the sinus node type is present in early embryonic mouse ventricular cells. In association with a loss of I(f) current, the ventricle tends to lose pacemaker potency during the second half of embryonic development.

Primary hepatocytes from mice treated with IL-2/IL-12 produce T cell chemoattractant activity that is dependent on monokine induced by IFN-gamma (Mig) and chemokine responsive to gamma-2 (Crg-2)

The IFN-gamma-inducible proteins monokine induced by IFN-gamma (Mig) and chemokine responsive to gamma-2 (Crg-2) can contribute to IL-12-induced antiangiogenic and leukocyte-recruiting activities, but the extent to which leukocytes vs parenchymal cells in different organs contribute to the production of these molecules remains unclear. The results presented herein show that IFN-gamma-dependent induction of Mig and Crg-2 gene expression can occur in many nonlymphoid organs, and these genes are rapidly induced in purified hepatocytes isolated from mice treated with IL-2 plus IL-12, or from Hepa 1-6 hepatoma cells treated in vitro with IFN-gamma. In addition to depending on IFN-gamma, the ability of IL-12 or IL-2/IL-12 to induce Mig and Crg-2 gene expression in purified hepatocytes also is accompanied by the coordinate up-regulation of the IFN-gamma R alpha and beta-chains, in the absence of IL-12R components. Supernatants of primary hepatocytes obtained from mice treated in vivo with IL-2/IL-12 or from hepatocytes treated in vitro with IFN-gamma contain increased chemotactic activity for enriched human and mouse CD3(+) T cells, as well as mouse DX5(+) NK cells. The hepatocyte-derived chemotactic activity for mouse T cells but not NK cells was ablated by Abs specific for Mig and Crg-2. These results suggest that parenchymal cells in some organs may contribute substantially to initiation and/or amplification of inflammatory or antitumor responses.

Interleukin-8 and intercellular adhesion molecule 1 regulation in oral epithelial cells by selected periodontal bacteria: multiple effects of Porphyromonas gingivalis via antagonistic mechanisms

Interaction of bacteria with mucosal surfaces can modulate the production of proinflammatory cytokines and adhesion molecules produced by epithelial cells. Previously, we showed that expression of interleukin-8 (IL-8) and intercellular adhesion molecule 1 (ICAM-1) by gingival epithelial cells increases following interaction with several putative periodontal pathogens. In contrast, expression of IL-8 and ICAM-1 is reduced after Porphyromonas gingivalis ATCC 33277 challenge. In the present study, we investigated the mechanisms that govern the regulation of these two molecules in bacterially infected gingival epithelial cells. Experimental approaches included bacterial stimulation of gingival epithelial cells by either a brief challenge (1.5 to 2 h) or a continuous coculture throughout the incubation period. The kinetics of IL-8 and ICAM-1 expression following brief challenge were such that (i) secretion of IL-8 by gingival epithelial cells reached its peak 2 h following Fusobacterium nucleatum infection whereas it rapidly decreased within 2 h after P. gingivalis infection and remained decreased up to 30 h and (ii) IL-8 and ICAM-1 mRNA levels were up-regulated rapidly 2 to 4 h postinfection and then decreased to basal levels 8 to 20 h after infection with either Actinobacillus actinomycetemcomitans, F. nucleatum, or P. gingivalis. Attenuation of IL-8 secretion was facilitated by adherent P. gingivalis strains. The IL-8 secreted from epithelial cells after F. nucleatum stimulation could be down-regulated by subsequent infection with P. gingivalis or its culture supernatant. Although these results suggested that IL-8 attenuation at the protein level might be associated with P. gingivalis proteases, the Arg- and Lys-gingipain proteases did not appear to be solely responsible for IL-8 attenuation. In addition, while P. gingivalis up-regulated IL-8 mRNA expression, this effect was overridden when the bacteria were continuously cocultured with the epithelial cells. The IL-8 mRNA levels in epithelial cells following sequential challenge with P. gingivalis and F. nucleatum and vice versa were approximately identical and were lower than those following F. nucleatum challenge alone and higher than control levels or those following P. gingivalis challenge alone. Thus, together with the protease effect, P. gingivalis possesses a powerful strategy to ensure the down-regulation of IL-8 and ICAM-1.

The analysis of resectability and survival in pancreatic cancer patients with vascular invasion

One of the major limitations of curative resection in patients with pancreatic cancer is local tumor extension to the mesenteric vessels. Thus, the purposes of our study were to assess the clinical value of contrast-enhanced spiral computed tomography (CT) in predicting the resectability and survival of patients with pancreatic cancer with suspicious vascular invasion and to assess the influence of curative resection on the survival of these patients. We enrolled 40 patients with pancreatic cancer who were suspected of having an involvement of the adjacent large vessels and who subsequently underwent operation with curative intent in the study. Resectability and survival were correlated with CT findings such as segment length, degree of encasement, and type and number of vessels involved. The survival rate was compared between the curative and palliative resection groups, and survival rate was compared between the resected and unresected groups. Of the 40 patients with adenocarcinoma of the pancreas, 14 had curative resections and 26 had palliative resections. The probability of curative resection was higher in patients with segment lengths less than 2 cm, as compared with segment lengths more than 2 cm. However, there was no difference in survival between the two groups. There were no differences in resectability and survival according to the degree of encasement and type and number of vessels involved. There was no difference in survival between the curative and palliative resection groups. There was no difference in survival between the resected and unresected groups. A survival benefit was not achieved by curative resection in patients with pancreatic cancer with vascular invasion. Therefore, it would be better to avoid aggressive surgery in patients with pancreatic cancer with vascular invasion.

High signal intensity of the posterior pituitary gland on T1-weighted MR images. Correlation with plasma vasopressin concentration to water deprivation

PURPOSE

To evaluate the effect of water deprivation on the signal intensity of the posterior pituitary gland on T1-weighted MR images and correlate the signal intensity with the plasma vasopressin concentration.

MATERIAL AND METHODS

Fifteen rabbits were studied: Group 1 (n=10) was deprived of water for 9 days and Group 2 (n=5) was replenished water for 7 days after 7-day water deprivation. MR imaging and plasma vasopressin measurement by radioimmunoassay were made before and after water deprivation and replenishment. Sequential changes of the signal intensity ratio of the posterior lobe to the pons and plasma vasopressin concentration were correlated.

RESULTS

Before water deprivation, the hyperintense posterior lobe was demonstrated in all rabbits. During water deprivation, the signal intensity ratio decreased and vasopressin concentration increased gradually. On the contrary, the signal intensity ratio increased and vasopressin concentration decreased with water replenishment. The signal intensity ratio correlated well with the plasma vasopressin concentration (p<0.05).

CONCLUSION

There was a negative, linear correlation between the signal intensity ratio of the posterior pituitary gland on T1-weighted MR images and plasma vasopressin concentration to water deprivation. The results support that the high signal intensity of the posterior pituitary gland on T1-weighted MR images is attributed to the normal content of vasopressin-neurosecretory granules.

Painless pediatric local anesthesia

This clinical report presents a technique for painless palatal/lingual infiltrations for pediatric patients. When treating a young child, pain control is very important in order to gain the patient's cooperation. Procedures such as clamp placement, operative techniques, pulp therapy, and extractions cause discomfort, some more than others, requiring profound anesthesia. However, achieving profound anesthesia painlessly in the palatal and lingual aspects is difficult.

Technetium-99m tetrofosmin scintigraphy for detecting malignant lymphoma

The aim of this study was to assess the use of Tc-99m tetrofosmin (Tc-TF) scintigraphy for detecting malignant lymphomas. In the study, before any chemotherapy, 50 patients with malignant lymphoma underwent Tc-TF scintigraphy, which was performed 10 minutes after intravenous injection of 20 mCt Tc-TF. Tc-TF scintigraphy detected malignant lymphoma in 44 (88%) patients. However, there were no significant differences in the incidences of positive and negative Tc-TF scintigraphic results between female versus male patients, HD versus NHL patients, stage I-II versus stage III-IV patients, age > 40 years versus < or = 40 years patients and patients with B symptoms false-negative results occurred in 4 (8%) infradiaphragmatic malignant lymphoma. We conclude patients with that Tc-TF scintigraphy appears suitable for detecting malignant lymphoma, especially supradiaphragmatic lesions.

Risk factors for hip fracture in Asian men and women: the Asian osteoporosis study

The objectives of the Asian Osteoporosis Study (AOS) were to determine risk factors for hip fracture in men and women in four Asian countries, that is, Singapore, Malaysia, Thailand, and the Philippines. A total of 451 men and 725 women (aged 50 years and over) with hip fractures were compared with an equal number of community controls. A standardized questionnaire was administered by interview. The following relative risks (RRs) were found in women and men by multiple logistic regression: dietary calcium intake < 498 mg/day, 2.0 for women (95% CI, 1.5-2.8) and 1.5 for men (95% CI, 1.0-2.2); no load bearing activity in the immediate past, 2.0 for women (95% CI, 1.4-2.7) and 3.4 for men (95% CI, 2.3-5.1); no vigorous sport activities in young adulthood, 7.2 for women (95% CI, 4.0-13.0) and 2.4 for men (95% CI, 1.6-3.6); cigarette smoking, 1.5 for men (95% CI, 1.0-2.1); alcohol consumption 7 days a week, 2.9 for women (95% CI, 1.0-8.6) and 1.9 for men (95% CI, 1.1-3.2); fell twice or more in the last 12 months, 3.0 for women (95% CI, 1.8-4.8) and 3.4 for men (95% CI, 1.8-6.6); a history of fractures after 50 years of age, 1.8 for women (95% CI, 1.1-2.9) and 3.0 for men (95% CI, 1.6-5.6); a history of stroke, 3.8 for women (95% CI, 2.0-7.1) and 3.6 for men (95% CI, 1.8-7.1); use of sedatives, 2.5 for women (95% CI, 1.0-6.3) and 3.0 for men (95% CI, 1.0-9.7); and use of thyroid drugs, 7.1 for women (95% CI, 2.0-25.9) and 11.8 for men (95% CI, 1.3-106.0). Women who were 1.56 m or taller had an RR of 2.0 (95% CI, 1.3-3.0) for hip fracture and men who were 1.69 m or taller had an RR of 1.9 (95% CI, 1.2-3.1) for hip fracture. Based on these findings, primary preventive programs for hip fracture could be planned in Asia.

Structure and expression of a CTP: phosphocholine cytidylyltransferase gene from Arabidopsis thaliana

A genomic clone, which includes the CTP: phosphocholine cytidylyltransferase (CCT) open reading frame and its 5'- and 3'- flanking non-coding regions, has been isolated from Arabidopsis thaliana and sequenced. The CCT gene is approximately 3.0 kb in length and contains 8 exons interrupted by 7 introns, which range from 74 to 626 nucleotides. All nucleotide sequences for the intron 3' splice sites are consistent with the consensus AG sequence of plant pre-mRNA processing, while the major GT consensus sequence for the 5' splice site is conserved in 5 of 7 introns. Introns 5 and 6 have a minor GC consensus sequence instead. In the 5'-flanking region there are two sequences related to a cold-responsive element found in the cold-inducible promoter of the A. thaliana cor15a gene, plus one gibberellin-response element. The results from reverse transcriptase-PCR indicate that the expression of A. thaliana CCT is regulated by temperature. The expression level of CCT increased after a 30-min treatment at 5 degrees C. When the plants were returned to 22 degrees C, the expression of CCT also decreased to the original level.

Inhibitory action of water soluble fraction of Terminalia chebula on systemic and local anaphylaxis

We investigated the effects of the water soluble fraction of Terminalia chebula (Combretaceae) (WFTC) on systemic and local anaphylaxis. WFTC administered 1h before compound 48/80 injection inhibited compound 48/80-induced anaphylactic shock 100% with doses of 0.01-1.0 g/kg. When WFTC was administered 5 or 10 min after compound 48/80 injection, the mortality also decreased in a dose-dependent manner. Passive cutaneous anaphylaxis was inhibited by 63.5+/-7.8% by oral administration of WFTC (1.0 g/kg). When WFTC was pretreated at concentrations ranging from 0.005 to 1.0 g/kg, the serum histamine levels were reduced in a dose-dependent manner. WFTC (0.01-1.0 mg/ml) also significantly inhibited histamine release from rat peritoneal mast cells (RPMC) by compound 48/80. However, WFTC (1.0 mg/ml) had a significant increasing effect on anti-dinitrophenyl IgE-induced tumor necrosis factor-alpha production from RPMC. These results indicate that WFTC may possess a strong antianaphylactic action.

Protective effect of green tea extract on ischemia/reperfusion-induced brain injury in Mongolian gerbils

Free radical-induced oxidative damages of macromolecules and cell death are important factors in the pathogenesis of ischemia/reperfusion brain injury. In the present study, an investigation as to whether green tea extract reduces ischemia/reperfusion-induced brain injury in Mongolian gerbils was conducted. The effect of green tea on the ischemia/reperfusion-induced production of hydrogen peroxide, lipid peroxidation and oxidative DNA damage (formation of 8-hydroxydeoxyguanosine), and cell death in addition to locomotor activity was studied. Two doses (0.5 or 2%) of green tea extract were added into the drinking water and to be accessed by animals ad libitum for 3 weeks prior to the induction of ischemia. A global ischemia was induced by the bilateral occlusion of the common carotid arteries for 5 min. Reperfusion was achieved by releasing the occlusion and restoring blood circulation for 48 h. The infarction volumes were 112+/-31 mm(3) and 76+/-11 mm(3) in the 0.5 and 2% green tea pretreated animals compared to 189+/-12 mm(3) in the ischemia/reperfusion animals. Green tea extract also reduced the levels of ischemia/reperfusion-induced hydrogen peroxide (from 1470+/-170 to 1034+/-46 and 555+/-30 nmole/mg protein), lipid peroxidation products (from 1410+/-210 to 930+/-40 and 330+/-20 nmole/mg protein) and 8-oxodG (from 3.9+/-0.1 to 2.8+/-0.3 and1.9+/-0.3 ng/microg DNA, x10(-2)) by pretreatment of 0.5 or 2% green tea for 3 weeks, respectively. Moreover, green tea also reduced the number of ischemia/reperfusion-induced apoptotic cells (from 59+/-12 to 37+/-8, 15+/-11 apoptotic cells/high power field in the striatum region) and locomotor activity (from 15140+/-2940 to 3900+/-600 and 4100+/-1200). This study therefore suggests that green tea may be a useful agent for the prevention of cerebral ischemia damage.

Processive DNA helicase activity of the minichromosome maintenance proteins 4, 6, and 7 complex requires forked DNA structures

The minichromosome maintenance (Mcm) proteins 2-7 are required for both the initiation and elongation steps of chromosomal DNA replication. Previous studies have shown that the Mcm complex consisting of the Mcm 4, 6, and 7 proteins contains 3' to 5' DNA helicase activity with limited processivity (displacing duplex DNA regions up to 30 nt). In this report, we show that the presence of both 5' and 3' single-stranded tails in DNA helicase substrates is essential for the processive helicase activity of the Mcm complex. The presence of both 5' and 3' tails facilitated the formation of double heterohexameric complexes of Mcm4/6/7 on substrate DNA, which appeared to be essential for the processive helicase activity. The double heterohexameric complex of Mcm4/6/7, in the presence of a single-strand DNA binding protein, is capable of unwinding duplex DNA region of about 600 bp in length. These results support the hypothesis that the Mcm4/6/7 complex can function as a replication helicase.

Human homologs of the Xenopus oocyte cortical granule lectin XL35

The cDNAs encoding two human homologs of the Xenopus oocyte lectin, XL35, were isolated from a small intestine cDNA library and termed HL-1 and HL-2. The deduced amino acid sequence of each homolog is about 60% identical and 80% similar to that of XL35, and none of these sequences contains the C-type lectin motif, although it is known that XL35 requires calcium for ligand binding. By Northern analysis, HL-1 transcripts are present at relatively high levels in heart, small intestine, colon, thymus, ovary, and testis. HL-2 transcripts, by contrast, are expressed only in small intestine. Immunocytochemistry using a polyclonal antibody produced against XL35 shows HL-1 protein to be localized exclusively in endothelial cells in colon, thymus, liver, and other tissues. Primary cultures of human aortic endothelial cells are positive for HL-1 expression by immunoblotting and by PCR analysis, but several other human cell types are not. HL-1 and -2 are both encoded at chromosome 1q23, the same locus that encodes the selectins. XL35, HL-1 and -2, and another mouse homolog are members of a new family of proteins whose members most likely perform diverse functions.

Chromosomal localization and genomic organization for the galactose/ N-acetylgalactosamine/N-acetylglucosamine 6-O-sulfotransferase gene family

The galactose/N-acetylgalactosamine/N-acetylglucosamine 6-O-sulfotransferases (GSTs) are a family of Golgi-resident enzymes that transfer sulfate from 3'phosphoadenosine 5'phospho-sulfate to the 6-hydroxyl group of galactose, N-acetylgalactosamine, or N-acetylglucosamine in nascent glycoproteins. These sulfation modifications are functionally important in settings as diverse as cartilage structure and lymphocyte homing. To date six members of this gene family have been described in human and in mouse. We have determined the chromosomal localization of these genes as well as their genomic organization. While the broadly expressed enzymes implicated in proteoglycan biosynthesis are located on different chromosomes, the highly tissue specific enzymes GST-3 and 4 are encoded by genes located both in band q23.1--23.2 on chromosome 16. In the mouse, both genes reside in the syntenic region 8E1 on chromosome 8. This cross-species conserved clustering is suggestive of related functional roles for these genes. The human GST4 locus actually contains two highly similar open reading frames (ORF) that are 50 kb apart and encode two highly similar enzyme isoforms termed GST-4 alpha and GST-4 beta. All genes except GST0 (chondroitin 6-O-sulfotransferase) contain intron-less ORFs. With one exception these are fused directly to sequences encoding the 3' untranslated regions (UTR) of the respective mature mRNAs. The 5' UTRs of these mRNAs are usually encoded by a number of short exons 5' of the respective ORF. 5'UTRs of the same enzyme expressed in different cell types are sometimes derived from different exons located upstream of the ORF. The genomic organization of the GSTs resembles that of certain glycosyltransferase gene families.

Paclitaxel-Based chemotherapy for non-small cell lung cancer: predicting the response with 99mTc-tetrofosmin chest imaging

The purpose of this study was to retrospectively predict the chemotherapeutic response to paclitaxel for non-small cell lung cancer (NSCLC) using 99mTc-tetrofosmin (TF) uptake and to detect the expression of 170-kDa multidrug resistance-mediated P-glycoprotein (MDR-Pgp).

METHODS

Before chemotherapy with paclitaxel, 20 patients with stage IIIb or IV NSCLC were enrolled in this study to undergo early and delayed 99mTc-TF chest imaging for calculating tumor-to-normal lung ratios (T/NL) and retention indices (RI) for assessment of the MDR-Pgp in NSCLC.

RESULTS

The early and delayed mean T/NLs were 1.59 +/- 0.25 and 1.50 +/- 0.25, respectively, for 10 patients with a good response and 1.09 +/- 0.09 and 1.03 +/- 0.05, respectively, for 10 patients with a poor response. The differences were shown to be significant (P < 0.001) by independent Student t tests. However, no significant differences (P = 0.801) between good-response patients (-5.70% +/- 3.67%) and poor-response patients (-5.23% +/- 4.51%) were found in RI. In addition, other prognostic factors (age, sex, tumor size, stage, and cell type) were not significantly different between good-response patients and poor-response patients.

CONCLUSION

99mTc-TF chest images are potential tools for understanding MDR-Pgp expression in NSCLC and for predicting the chemotherapeutic response to paclitaxel.

Distal anterior choroidal artery aneurysm in a patient with moyamoya disease: case report

OBJECTIVE AND IMPORTANCE

Distal anterior choroidal artery (AChA) aneurysms in moyamoya disease are rare, with few surgically verified reported cases.

CLINICAL PRESENTATION

We report a rare case of distal AChA aneurysm associated with moyamoya disease in a 48-year-old man who presented with vomiting and severe headache. Computed tomographic scans revealed an intracerebral hematoma in the right temporoparietal lobe and a diffuse intraventricular hemorrhage.

INTERVENTION

The hematoma was removed via computed tomography-guided stereotactic aspiration and ventricular drainage. Cerebral angiography showed a saccular aneurysm located at the distal branch of the right AChA. By means of magnetic resonance imaging, a small signal void lesion was detected in the periventricular area lateral to the trigone of the right lateral ventricle. The aneurysm was accurately accessed via a parietal cortical incision by use of magnetic resonance imaging-guided stereotactic localization. The aneurysm was successfully resected after undergoing trapping of the parent artery, and when the patient was discharged, he had no evidence of neurological deficit. The aneurysm was histologically verified to be a true aneurysm.

CONCLUSION

Direct surgery should be considered in cases of ruptured distal AChA aneurysms located in the periventricular or intraventricular regions.

Development and application of a sorption data base for the performance assessment of a radwaste repository

A sorption data base (SDB) provides readily available data for the performance assessment of a radwaste repository when site-specific and/or reference data are needed. The software developed at KAERI, SDB-21C, is a graphic user interface (GUI) program that provides efficient and user-friendly tools for evaluating large amount of sorption data. In addition, the most comprehensive sorption data base that contains about 11,000 NEA data and 2,000 KAERI data was compiled in the program. Besides the simple Kd approach, a parametric model and its compiled data sets are also included in the SDB-21C. In order to evaluate the versatility of SDB-21C, several applications were performed for relevant hypothetical situations.

The incidence of hip fracture in four Asian countries: the Asian Osteoporosis Study (AOS)

The Asian Osteoporosis Study (AOS) is the first multicenter study to document and compare the incidence of hip fracture in four Asian countries. Hosital discharge data for the year 1997 were obtained for the Hong Kong SAR, Singapore, Malaysia and Thailand (Chiang Mai). The number of patients who were 50 years of age and older and who were discharged with a diagnosis of hip fracture (ICD9 820) was enumerated. The age-specific incidence rates were deduced and were directly adjusted to the US white population in 1989. The age-adjusted rates for men and women (per 100,000) are as follows: Hong Kong, 180 and 459; Singapore, 164 and 442; Malaysia, 88 and 218; Thailand, 114 and 289; compared with US White rates of 187 in men and 535 in women, published in 1989. We conclude that there is moderate variation in the incidence of hip fracture among Asian countries. The rates were highest in urbanized countries. With rapid economic development in Asia, hip fracture will prove to be a major public health challenge.

Sulfation of N-acetylglucosamine by chondroitin 6-sulfotransferase 2 (GST-5)

Based on sequence homology with a previously cloned human GlcNAc 6-O-sulfotransferase, we have identified an open reading frame (ORF) encoding a novel member of the Gal/GalNAc/GlcNAc 6-O-sulfotransferase (GST) family termed GST-5 on the human X chromosome (band Xp11). GST-5 has recently been characterized as a novel GalNAc 6-O-sulfotransferase termed chondroitin 6-sulfotransferase-2 (Kitagawa, H., Fujita, M., Itio, N., and Sugahara K. (2000) J. Biol. Chem. 275, 21075-21080). We have coexpressed a human GST-5 cDNA with a GlyCAM-1/IgG fusion protein in COS-7 cells and observed four-fold enhanced [(35)S]sulfate incorporation into this mucin acceptor. All mucin-associated [(35)S]sulfate was incorporated as GlcNAc-6-sulfate or Galbeta1-->4GlcNAc-6-sulfate. GST-5 was also expressed in soluble epitope-tagged form and found to catalyze 6-O-sulfation of GlcNAc residues in synthetic acceptor structures. In particular, GST-5 was found to catalyze 6-O-sulfation of beta-benzyl GlcNAc but not alpha- or beta-benzyl GalNAc. In the mouse genome we have found a homologous ORF that predicts a novel murine GlcNAc 6-O-sulfotransferase with 88% identity to the human enzyme. This gene was mapped to mouse chromosome X at band XA3.1-3.2. GST-5 is the newest member of an emerging family of carbohydrate 6-O-sulfotransferases that includes chondroitin 6-sulfotransferase (GST-0), keratan-sulfate galactose 6-O-sulfotransferase (GST-1), the ubiquitously expressed GlcNAc 6-O-sulfotransferase (GST-2), high endothelial cell GlcNAc 6-O-sulfotransferase (GST-3), and intestinal GlcNAc 6-O-sulfotransferase (GST-4).

Caveolin-3 directly interacts with the C-terminal tail of beta -dystroglycan. Identification of a central WW-like domain within caveolin family members

Caveolin-3, the most recently recognized member of the caveolin gene family, is muscle-specific and is found in both cardiac and skeletal muscle, as well as smooth muscle cells. Several independent lines of evidence indicate that caveolin-3 is localized to the sarcolemma, where it associates with the dystrophin-glycoprotein complex. However, it remains unknown which component of the dystrophin complex interacts with caveolin-3. Here, we demonstrate that caveolin-3 directly interacts with beta-dystroglycan, an integral membrane component of the dystrophin complex. Our results indicate that caveolin-3 co-localizes, co-fractionates, and co-immunoprecipitates with a fusion protein containing the cytoplasmic tail of beta-dystroglycan. In addition, we show that a novel WW-like domain within caveolin-3 directly recognizes the extreme C terminus of beta-dystroglycan that contains a PPXY motif. As the WW domain of dystrophin recognizes the same site within beta-dystroglycan, we also demonstrate that caveolin-3 can effectively block the interaction of dystrophin with beta-dystroglycan. In this regard, interaction of caveolin-3 with beta-dystroglycan may competitively regulate the recruitment of dystrophin to the sarcolemma. We discuss the possible implications of our findings in the context of Duchenne muscular dystrophy.

Short-term safety and tolerability of antihypertensive agents in Korean patients: an observational study

PURPOSE

In order to assess the short-term safety and tolerability of newly prescribed antihypertensive monotherapies in Korean patients, a prospective study was carried out.

METHODS

A total of 1181 patients were observed from July 1997 to August 1999. At 2, 4, 8 and 12 weeks after initiation of antihypertensive monotherapy, the patients were evaluated for whether treatment was to be continued and the development of any adverse reactions.

RESULTS

During the first 12 weeks, the percentage of subjects continuing with their initial angiotensin converting enzyme inhibitors (ACEI) (40.7%) was substantially lower than that of subjects continuing with angiotensin II receptor antagonists (ARA) (66.2%), alpha-blockers (63.0%), calcium channel blockers (CCB) (61.3%), beta-blockers (55.8%), and diuretics (53.5%), respectively (P < 0.01). The following adverse reactions were detected: cough (7.5%), headache (6.1%), dizziness (3.9%), flushing (3.7%) and impotence (2.4%). Cough, headache, and flushing were more frequent in women, and impotence and loss of libido were more frequent in men (P < 0.05). The incidence of cough associated with ACEI (27.9%) was higher than that associated with the other classes of drugs (P < 0.01).

CONCLUSIONS

The tolerability of antihypertensive medication was highest in Korean patients treated with ARAs, followed by CCBs, beta-blockers, diuretics, alpha-blockers, and ACEIs. The incidences of adverse reactions were different by sex, age and drug class.

Overexpression of cyclin D1 and cyclin E in 1,2-dimethylhydrazine dihydrochloride-induced rat colon carcinogenesis

Deregulation of G1 cyclins has been reported in several human and rodent tumors including colon cancer. To investigate the expression pattern of G1 cyclins in 1,2- dimethyl-hydrazine dihydrochloride (DMH)-induced rat colon carcinogenesis, we studied the expression of cyclin D1 and cyclin E by quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis and immunohistochemistry (IHC). The mRNA level of cyclin D1 was increased 1.2-fold in adenocarcinomas but not significantly in adenomas, when compared with normal rat colonic mucosa (p<0.05). The cyclin E mRNA level was increased 2.7-fold in adenomas and 3.3-fold in adenocarcinomas (p<0.05). The PCNA mRNA level was also increased 1.9-fold in adenomas and 1.8-fold in adenocarcinomas (p<0.05). Immunohistochemical staining revealed exclusive nuclear staining of the neoplastic cells for cyclin D1, cyclin E and PCNA. Cyclin D1 expression was detected in 56.3% of the adenomas and in 61.5% of the adenocarcinomas examined, whereas cyclin E expression was detected in 87.5% of the adenomas and in 92.3% of the adenocarcinomas. Overall, cyclin D1, cyclin E and PCNA expression was significantly increased at both the mRNA and protein levels in normal colonic mucosa, adenomas and adenocarcinomas, but there was no significant difference in the degree of expression of these genes in adenomas and adenocarcinomas. Our results indicate that the overexpression of cyclin D1 and cyclin E may play an important role during the multistage process of rat colon carcinogenesis, at a relatively early stage, and may disturb cell-cycle control in benign adenomas, and thereafter, participate in tumor progression.

Rate-control versus conversion strategy in postoperative atrial fibrillation: a prospective, randomized pilot study

BACKGROUND

Atrial fibrillation remains a frequent complication after heart surgery. The optimal strategy to treat the condition has not been established. Several retrospective studies have suggested that a primary rate-control strategy may be equivalent to a strategy that restores sinus rhythm.

METHODS

Fifty patients with atrial fibrillation after heart surgery were randomly assigned to a strategy of antiarrhythmic therapy with or without electrical cardioversion or ventricular rate control. Both arms received anticoagulation with heparin overlapped with warfarin. The primary end point was time to conversion to sinus rhythm analyzed by the Kaplan-Meier method. Atrial fibrillation relapse after the initial conversion was monitored in the hospital over a 2-month period.

RESULTS

There was no significant difference between an antiarrhythmic conversion strategy (n = 27) and a rate-control strategy (n = 23) in time to conversion to sinus rhythm (11.2 +/- 3. 2 vs 11.8 +/- 3.9 hours; P =.8). With the use of Cox multivariate analysis to control for the effects of age, sex, beta-blocker usage, and type of surgery, the antiarrhythmic strategy showed a trend toward reducing the time from treatment to restoration of sinus rhythm (P =.08). The length of hospital stay was reduced in the antiarrhythmic arm compared with the rate-control strategy (9.0 +/- 0.7 vs 13.2 +/- 2.0 days; P =.05). In-hospital relapse rates in the antiarrhythmic arm were 30% compared with 57% in the rate-control strategy (P =.24). There were no significant difference in relapse rates at 1 week (24% vs 28%), 4 weeks (6% vs 12%), and 6 to 8 weeks (4% vs 9%). At the end of the study, 91% of the patients in the rate-control arm were in sinus rhythm compared with 96% in the antiarrhythmic arm (P =.6).

CONCLUSIONS

This pilot study shows little difference between a rate-control strategy and a strategy to restore sinus rhythm. Regardless of strategy, most patients will be in sinus rhythm after 2 months. A larger randomized, controlled study is needed to assess the impact of restoration of sinus rhythm on length of stay.

Neuroprotective effect of green tea extract in experimental ischemia-reperfusion brain injury

Eicosanoids accumulation and formation of oxygen free radicals have been implicated in the pathogenesis of ischemia/reperfusion brain injury. In the present study, we examined whether green tea extract protects against ischemia/reperfusion-induced brain injury by minimizing eicosanoid accumulation and oxygen radical-induced oxidative damage in the brain. Green tea extract (0.5%) was orally administered to Wistar rats for 3 weeks before induction of ischemia. Ischemia was induced by the occlusion of middle cerebral arteries for 60 min and reperfusion was achieved for 24 h. Infarction volume in the ipsilateral hemisphere of ischemia/reperfusion animals was 114 +/- 16 mm(3) in the 0.5% green tea pretreated animals compared to 180 +/- 54 mm(3) in left hemisphere of nontreated animals. Green tea extract (0.5%) also reduced ischemia/reperfusion-induced eicosanoid concentration: Leukotriene C(4) (from 245 +/- 51 to186 +/- 22), prostoglandin E(2) (from 306 +/- 71 to 212 +/- 43) and thromboxane A(2) (327 +/- 69 to 251 +/- 87 ng/mg protein). Ischemia/reperfusion-induced increases of hydrogen peroxide level (from 688 +/- 76 to 501 +/- 99 nmole/mg protein), lipid peroxidation products (from 1010 +/- 110 to 820 +/- 70 nmole/mg protein) and 8-oxodG formation (from 1.3 +/- 0.3 to 0.8 +/- 0.2 ng/microg DNA, x10(-2)) were also reduced. Moreover, 0.5% green tea extract also reduced the apoptotic cell number (from 44 +/- 11 to 29 +/- 1 in the striatum, and from 72 +/- 11 to 42 +/- 5 apoptotic cells/high power field in the cortex region). Green tea extract pretreatment also promoted recovery from the ischemia/reperfusion-induced inhibition of active avoidance. The present study shows that the minimizing effect of green tea extract on the eicosanoid accumulation and oxidative damage in addition to the reduction of neuronal cell death could eventually result in protective effect on the ischemia/reperfusion-induced brain injury and behavior deficit.

Residues and mechanisms for slow activation and Ba2+ block of the cardiac muscarinic K+ channel, Kir3.1/Kir3.4

Mechanisms and residues responsible for slow activation and Ba(2+) block of the cardiac muscarinic K(+) channel, Kir3.1/Kir3.4, were investigated using site-directed mutagenesis. Mutagenesis of negatively charged residues located throughout the pore of the channel (in H5, M2, and proximal C terminus) reduced or abolished slow activation. The strongest effects resulted from mutagenesis of residues in H5 close to the selectivity filter; mutagenesis of residues in M2 and proximal C terminus equivalent to those identified as important determinants of the activation kinetics of Kir2.1 was less effective. In giant patches, slow activation was present in cell-attached patches, lost on excision of the patch, and restored on perfusion with polyamine. Mutagenesis of residues in H5 and M2 close to the selectivity filter also decreased Ba(2+) block of the channel. A critical residue for Ba(2+) block was identified in Kir3.4. Mutagenesis of the equivalent residue in Kir3.1 failed to have as pronounced an effect on Ba(2+) block, suggesting an asymmetry of the channel pore. It is concluded that slow activation is principally the result of unbinding of polyamines from negatively charged residues close to the selectivity filter of the channel and not an intrinsic gating mechanism. Ba(2+) block involves an interaction with the same residues.

Observation of low molecular weight poly(methylsilsesquioxane)s by graphite plate laser desorption/ionization time-of-flight mass spectrometry

Mass spectra of polystyrene and poly(methylsilsesquioxane)(PMSSQ) derived from methyltriethoxysilane(MTES) were obtained in the 100-1,000 Da range by laser desorption/ionization time-of-flight mass spectrometry using a graphite plate without a matrix. Clean mass spectra were obtained without interference from carbon clusters or other low molecular weight compounds. Initial reaction products derived from condensation of partially hydrolyzed MTES were observed. Upon 30 min of heating at 30 degrees C, the ethoxy groups were fully hydrolyzed to hydroxy groups. Many PMSSQ species consistent with predictable polymerization reaction pathways involving intermolecular condensation and intramolecular dehydration were observed. Thus, laser desorption/ionization time-of-flight mass spectrometry using a graphite plate, without added matrix materials, is shown to provide valuable information on low molecular weight polymer not available by MALDI-TOF-MS.

Elevated plasma levels of matrix metalloproteinase-9 in patients with abdominal aortic aneurysms: a circulating marker of degenerative aneurysm disease

PURPOSE

Matrix metalloproteinase-9 (MMP-9) is abundantly expressed in abdominal aortic aneurysms (AAAs), where it plays a pivotal role in connective tissue destruction. Elevated plasma concentrations of MMP-9 (MMP-9PL) also have been reported in patients with AAAs, but it is unclear if this can distinguish patients with AAAs from those with atherosclerotic occlusive disease (AOD). The purpose of this study was to further define the utility of elevated MMP-9PL levels in the diagnosis and evaluation of AAAs, and to examine if changes in MMP-9PL can be used as a functional biomarker of degenerative aneurysm disease.

MATERIALS AND METHODS

Peripheral venous blood was obtained from 25 patients with AAAs, 15 patients with AOD, and five normal control subjects. MMP-9PL levels were determined by an enzyme-linked immunosorbent assay. In four patients undergoing open AAA repair, MMP-9PL levels were directly compared with the amount of MMP-9 produced in aortic tissue. Six additional patients undergoing operative AAA repair were followed for 3-10 months to determine how treatment affected elevated MMP-9PL concentrations.

RESULTS

Mean (+/- SE) MMP-9PL was 36.1 +/- 7.7 ng/mL in normal control subjects, 54.7 +/- 10.5 ng/mL in patients with AOD, and 99.4 +/- 17.4 ng/mL in patients with AAAs (P < .05 versus normal control subjects and patients with AOD). Elevated MMP-9PL levels (> 87.8 ng/mL) were found in 12 of 25 (48%) patients with AAA but in only one of 15 (7%) patients with AOD (P < .05). MMP-9PL levels did not correlate significantly with either age, gender, or aneurysm diameter, although there was a trend toward the highest values in male patients with large AAAs. Production of MMP-9 in aneurysm tissues paralleled MMP-9PL levels, and elevated MMP-9PL levels decreased by 92.7% +/- 3.2% after surgical AAA repair.

CONCLUSIONS

Elevated MMP-9PL levels were observed in approximately one half of patients with AAAs and less than 10% of those with AOD (positive predictive value of 92.3%), but normal MMP-9PL levels had limited utility in excluding the presence of an aortic aneurysm (negative predictive value, 52%). MMP-9PL levels in patients with AAAs appeared to directly reflect the amount of MMP-9 produced within aneurysm tissue, and MMP-9PL levels decreased substantially after aneurysm repair. Measures of circulating MMP-9 may provide a biologically relevant marker of connective tissue metabolism in patients with AAAs.

A new caffeoyl quinic acid from aster scaber and its inhibitory activity against human immunodeficiency virus-1 (HIV-1) integrase

The phytochemical study of the aerial parts of Aster scaber Thunb. (Asteraceae) yielded a new caffeoyl quinic acid, (-) 3,5-dicaffeoyl-muco-quinic acid (2) and three known compounds, (-) 3,5-dicaffeoyl quinic acid (1), (-) 4,5-dicaffeoyl quinic acid (3), (-) 5-caffeoyl quinic acid (4). The structures were established by high resolution spectroscopic methods. The antiviral effects against HIV-1 integrase of the compounds was evaluated. (-) 3,5-Dicaffeoyl-muco-quinic acid (2) exhibited potent antiviral activity with an IC50 value of 7.0 +/- 1.3 microg/ml.

Complications and results of subdural grid electrode implantation in epilepsy surgery

BACKGROUND

We assessed the risk of delayed subdural hematoma and other complications associated with subdural grid implantation.

METHODS

Forty-nine patients underwent subdural grid implantation with/without subdural strips or depth electrodes from January 1994 to August 1998. To identify the risk associated with subdural grid implantation, a retrospective review of all patients' medical records and radiological studies was performed.

RESULTS

The major complications of 50 subdural grid electrode implantations were as follows: four cases (7.8%) of delayed subdural hematoma at the site of the subdural grid, requiring emergency operation; two cases (3.9%) of infection; one case (2.0%) of epidural hematoma; and one case (2.0%) of brain swelling. After subdural hematoma removal, the electrodes were left in place. CCTV monitoring and cortical stimulation studies were continued thereafter. No delayed subdural hematoma has occurred since routine placement of subdural drains was begun.

CONCLUSIONS

In our experience the worst complication of subdural grid implantation has been delayed subdural hematoma. Placement of subdural drains and close observation may be helpful to prevent this serious complication.

Activity of voriconazole against Candida albicans and Candida krusei isolated since 1984

With the recent dramatic rise in fluconazole use, there has been an increase in Candida species resistant to that agent. This has led to the clinical development of newer triazoles such as voriconazole that have greater potency and a broader spectrum of activity. We therefore hypothesized that fluconazole-resistant Candida albicans and Candida krusei would be susceptible to voriconazole. Susceptibility testing was performed on 205 isolates of C. albicans collected from 1984 to 1995, and on C. albicans and C. krusei that were identified as fluconazole resistant since 1995. The anti fungal agents used were amphotericin B, 5-flucytosine, itraconazole, ketoconazole, fluconazole and voriconazole. Three C. albicans and 26 C. krusei isolates had a minimum inhibitory concentration (MIC) >/=20 mg/l and were defined as fluconazole resistant. Of these, 28 isolates were susceptible to </=2.5 mg/l voriconazole, with a mean MIC of 0.78 mg/l. The mean amphotericin B MIC for these same strains was 0.98 mg/l. Only one isolate of C. krusei was relatively resistant to voriconazole with a MIC of 5 mg/l. Of these 29 isolates, there were ten amphotericin-resistant strains of C. krusei (MIC>2 mg/l) but all were susceptible to </=2.5 mg/l voriconazole. The higher potency of voriconazole may be useful in the treatment of fluconazole- and amphotericin-resistant C. albicans and C. krusei.

Efficacy and safety of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. Multicenter phase III clinical trials. Efficacy of early imaging

The efficacy of contrast-enhanced magnetic resonance imaging (MRI) for detecting and characterizing, or excluding, hepatic masses was assessed in 404 patients, following the intravenous administration of mangafodipir trisodium (MnDPDP) injection, a hepatic MRI contrast agent. An initial contrast-enhanced computed tomography (CT) examination was followed by unenhanced MRI, injection of MnDPDP (5 micromol/kg IV), and enhanced MRI at 15 minutes post injection. Agreement of the radiologic diagnoses with the patients' final diagnoses was higher for enhanced MRI and for the combined unenhanced and enhanced MRI evaluations than for unenhanced MRI alone or enhanced CT using the clinical diagnosis as the gold standard. Mangafodipir-enhanced MRI uniquely provided additional diagnostic information in 48% of the patients, and patient management was consequently altered in 6% of the patients. MnDPDP-enhanced MRI was comparable or superior to unenhanced MRI and enhanced CT for the detection, classification, and diagnosis of focal liver lesions in patients with known or suspected focal liver disease.

Performance of Markov chain-Monte Carlo approaches for mapping genes in oligogenic models with an unknown number of loci

Markov chain-Monte Carlo (MCMC) techniques for multipoint mapping of quantitative trait loci have been developed on nuclear-family and extended-pedigree data. These methods are based on repeated sampling-peeling and gene dropping of genotype vectors and random sampling of each of the model parameters from their full conditional distributions, given phenotypes, markers, and other model parameters. We further refine such approaches by improving the efficiency of the marker haplotype-updating algorithm and by adopting a new proposal for adding loci. Incorporating these refinements, we have performed an extensive simulation study on simulated nuclear-family data, varying the number of trait loci, family size, displacement, and other segregation parameters. Our simulation studies show that our MCMC algorithm identifies the locations of the true trait loci and estimates their segregation parameters well-provided that the total number of sibship pairs in the pedigree data is reasonably large, heritability of each individual trait locus is not too low, and the loci are not too close together. Our MCMC algorithm was shown to be significantly more efficient than LOKI (Heath 1997) in our simulation study using nuclear-family data.

Beta-2-microglobulin (beta 2M) as a tumor marker in nasopharyngeal carcinoma

The purpose of this study was to assess the clinical value of serum beta-2-microglobulin (beta 2M) in patients with nasopharyngeal carcinoma (NPC). beta 2M levels were assayed in 145 Taiwanese patients with untreated NPC, including 100 squamous cell carcinomas (SCC) and 45 undifferentiated carcinomas. The 145 NPC patients were separated into different subgroups based on the International Union Against Cancer (UICC) TNM classification system. In addition, 50 healthy subjects without any evidence of malignancy or other systemic diseases were included as controls. The results showed that (1) the mean serum, beta 2M level of the 145 NPC patients was higher than that of the 50 healthy controls and (2) the mean serum beta 2M levels of NPC patients who were male, older, with SCC, with higher TNM stages, and with a shorter survival time were higher than those patients who were female, younger, with undifferentiated carcinomas, with lower TNM stages, and with a longer survival time. However, none of the differences were significant. In addition, the overall detecting sensitivity of beta 2M for NPC was only 24.1%, and the detecting sensitivities in NPC patients who were male, older, with SCC, with higher TNM stages, and with a shorter survival time were higher than those of patients who were female, younger, with undifferentiated carcinomas, with lower TNM stages, and with a longer survival time. However, these differences also were not significant. In conclusion, our results suggest the beta 2M may have limited clinical potential as a valuable tumor marker for NPC.

Plasma endothelin levels are unaltered by thyroid hormone status in humans

Endothelin is a novel potent vasoconstrictor peptide produced by a wide variety of cell types and which has diverse biological activities. Previously we have reported that thyroid hormone status alters tissue levels of immunoreactive endothelin (irET) in rats. In order to study whether plasma irET levels in humans are affected by thyroid hormone status, we measured irET concentrations by means of radioimmunoassay in plasma samples from euthyroid controls as well as from patients with either hypothyroidism or hyperthyroidism. Plasma samples from the above-mentioned three groups of subjects were collected. After extraction with Sep-Pak C18 cartridges, plasma irET levels were measured by radioimmunoassay. The plasma irET levels in the three groups of subjects did not show any significant difference. Also, no correlations were found between plasma irET levels, thyroid hormones and the thyroid-stimulating hormone thyrotropin (TSH) in euthyroid, hypothyroid and hyperthyroid subjects. These results suggest that thyroid function per se is not a major determinant of plasma irET levels in humans.

Distinct human T cell repertoires mediate immediate and delayed-type hypersensitivity to the Trichophyton antigen, Tri r 2

The 29-kDa subtilase homologue, Tri r 2, derived from the dermatophyte fungus Trichophyton rubrum, exhibits unique immunologic characteristics in its ability to elicit immediate (IH) and delayed-type (DTH) hypersensitivity skin tests in different individuals. Thus, Tri r 2 provides a model for comparing the T cell repertoire in subjects with distinct immune responses to a single Ag. Recombinant Tri r 2 produced as a GST fusion protein in Escherichia coli stimulated strong in vitro lymphoproliferative responses in 10 IH and 10 DTH responders. Patterns of T cell epitope recognition were compared between skin test groups using 28 overlapping peptides (each in 12 replicate wells) derived from Tri r 2 to stimulate T lymphocyte proliferation in vitro. Peptide 5 (P5; aa 41-60) induced the strongest response in DTH subjects and showed the largest difference between DTH and IH responders in proliferation (mean standardized index, 2.22 and 0.82, respectively; p = 0.0047) and number of positive wells (81 vs 12). Responses to P5 were associated with diverse HLA haplotypes. These results showed that P5 contains an immunodominant epitope specifically associated with DTH and that this peptide is recognized in a permissive manner. Cross-validated linear discriminant analysis using T cell proliferative responses to two regions of Tri r 2 (aa 51-90 and 231-270) gave a 95% predictive accuracy for classification of subjects into IH or DTH groups. We conclude that different immune responses to Trichophyton are mediated by distinct T cell repertoires between individuals with IH and DTH reactions to Tri r 2.

Evidence of abnormal esophageal motility in syndrome X by radionuclide esophageal transit test

In 30 patients with syndrome X, esophageal motility was evaluated by radionuclide esophageal transit test (RETT). Esophageal motility measurements included esophageal mean transit time (MTT), residual fraction (RF), and retrograde index (RI). In comparison with 25 age- and sex-matched healthy volunteers, 66% of the patients with syndrome X had abnormal RETT findings including 50% of cases with longer MTT, 50% of cases with higher RF, and 33% of cases with higher RI. In addition, the mean values of MTT, RF, and RI in patients with syndrome X were significantly higher than those of healthy volunteers. We conclude that abnormal esophageal motility occurred in a large portion of syndrome X patients based on an simple and noninvasive RETT.

Cloning and expression of the ccpA gene encoding catabolite control protein from Thermoactinomyces sp. E79

The gene ccpA encoding the catabolite control protein A (CcpA) of Thermoactinomyces sp. E79 has been cloned and characterized. Nucleotide sequence analysis of the CcpA clone showed that the cloned fragment contained the full structural gene for a protein of 346 amino acids. The predicted amino acid sequence shows similarity to the transcriptional regulators of the Lacl-GalR family; a highly conserved helix-turn-helix motif, which might bind to DNA, was identified through comparison with regulator proteins in this family. The highest sequence identity was obtained when it was compared with the CcpA of Bacillus subtilis (60%) or Bacillus megaterium (60%). The expression of ccpA in Thermoactinomyces sp. E79 was dependent on glucose, which is contrast to the cases of B. subtilis, B. megaterium and S. xylosus. The complementation experiment with the B. megaterium ccpA mutant indicated that the cloned gene was a ccpA.