The inhibitory effects of thiopental, midazolam, and ketamine on human neutrophil functions

We investigated the effect of thiopental, midazolam, and ketamine (at clinically relevant concentrations and at 0.1 and 10 times these concentrations) on several aspects of human neutrophil functions. The three intravenous (i.v.) anesthetics significantly decreased chemotaxis, phagocytosis, and reactive oxygen species (ROS) (O2-, H2O2, OH) production of neutrophils in a dose-dependent manner. At clinically relevant concentrations, thiopental and midazolam significantly depressed these neutrophil functions. However, ketamine at the clinical plasma concentration did not impair chemotaxis or ROS production, except phagocytosis. In contrast, the three anesthetics had no effect on the levels of ROS production by a cell-free ROS generating system. In addition, intracellular calcium concentrations in neutrophils stimulated by N-formyl-L-methionyl-L-leucil-L-phenylalanine were dose-dependently decreased in the presence of each of the three anesthetics. The suppression of an increase in intracellular calcium concentrations may be responsible for the inhibition of neutrophil functions by the i.v. anesthetics.

IMPLICATIONS

Neutrophils play an important role in the antibacterial host defense system and autotissue injury. We found that thiopental and midazolam (but not ketamine), at clinically relevant concentrations, impaired the neutrophil functions.

Leaf-specifically expressed genes for polypeptides destined for chloroplasts with domains of sigma70 factors of bacterial RNA polymerases in Arabidopsis thaliana

Genes for sigma-like factors of bacterial-type RNA polymerase have not been characterized from any multicellular eukaryotes, although they probably play a crucial role in the expression of plastid photosynthesis genes. We have cloned three distinct cDNAs, designated SIG1, SIG2, and SIG3, for polypeptides possessing amino acid sequences for domains conserved in sigma70 factors of bacterial RNA polymerases from the higher plant Arabidopsis thaliana. Each gene is present as one copy per haploid genome without any additional sequences hybridized in the genome. Transient expression assays using green fluorescent protein demonstrated that N-terminal regions of the SIG2 and SIG3 ORFs could function as transit peptides for import into chloroplasts. Transcripts for all three SIG genes were detected in leaves but not in roots, and were induced in leaves of dark-adapted plants in rapid response to light illumination. Together with results of our previous analysis of tissue-specific regulation of transcription of plastid photosynthesis genes, these results indicate that expressed levels of the genes may influence transcription by regulating RNA polymerase activity in a green tissue-specific manner.

Intrinsic nucleoside diphosphate kinase-like activity as a novel function of 14-3-3 proteins

14-3-3 proteins play a role in many cellular functions as molecular chaperone and adapter proteins: they bind to and modulate several proteins involved in cell proliferation and differentiation, and also function ATP-dependently in targeting of precursors to mitochondria. We show here that 14-3-3 purified from a human lymphoblastoma and also its recombinant tau isoform exhibited intrinsic nucleoside diphosphate (NDP) kinase-like activity. 14-3-3 proteins preferentially catalyzed the transfer of the gamma-phosphate group from ATP, dATP or dGTP to all nucleoside diphosphates and this transfer involved acid-labile phosphoenzyme intermediates. They also simultaneously catalyzed the reverse reaction of ATP hydrolysis. These properties of 14-3-3 are similar to those of NDP kinase, but not to those of adenylate kinase.

Regression of superficial gastric MALT lymphoma with unsuccessful eradication therapy for Helicobacter pylori infection

A 51-year-old man had a reddish flat granular lesion in the stomach on endoscopic examination. Histology of biopsied specimen confirmed the diagnosis of low-grade B-cell gastric lymphoma of mucosa-associated lymphoid tissue (gastric MALT lymphoma) and simultaneous infection with Helicobacter pylori. He was given antibiotic treatment. Five weeks later, endoscopy and histology of biopsied specimen showed eradication of H. pylori, and the tumor had regressed. Six months later, H. pylori reemerged, but the tumor had not recurred. After the second antibiotic therapy, H. pylori has been eradicated. The lymphoma has been in remission for 14 months.

Kinetics of fibroblasts in ulcer healing in rats: interference with indomethacin

OBJECTIVE

The authors reported that the repair of submucosal tissue is important in ulcer healing. The kinetics of fibroblasts have not been well known in gastric ulcer healing. The effect of subcutaneous administration of indomethacin (1 mg/kg) to submucosal tissue was also examined.

METHOD

Immunohistological staining was done using the antibodies for the proliferating cell nuclear antigen prolyl 4-hydroxylase and alpha-smooth muscle actin in acetic acid induced gastric ulcers in rats. The terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate-biotin nick end labeling method was also employed.

RESULTS

The granulation tissue consisted predominantly of lymphocytes in indomethacin-treated rats. In the control group, proliferative cell nuclear antigen positive cells were at their peak 5 days after ulcer formation (day 5). Prolyl 4-hydroxylase positive fibroblasts were maximal on day 10. Alpha-smooth muscle actin positive myofibroblasts were few on day 5 and increased on day 15. In terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate-biotin nick end labeling, positive cells were sporadically seen on days 20 and 30. In indomethacin-administered rats, the fibroblasts proliferated weakly. The numbers of prolyl 4-hydroxylase and alpha-smooth muscle actin positive spindle-shaped cells were fewer and their appearance delayed. Nick end labeling positive cells were few before day 30 and sporadically observed on days 50 and 80.

CONCLUSION

The results indicate that fibroblasts differentiated into several phenotypes and finally underwent apoptosis.

Endoscopic ultrasonography in the diagnosis of submucosal lesions of the large intestine

BACKGROUND

Although reports of colorectal submucosal tumors have increased since the development of endoscopic examinations, precise diagnosis of these lesions remains difficult. In this study, we evaluated the usefulness of endoscopic ultrasonography (EUS) in the diagnosis of submucosal lesions of the large intestine.

METHODS

From September 1989 to June 1996, EUS was performed in 46 patients who were suspected to have submucosal lesions by barium enema or colonoscopy. Twenty-seven of the 46 cases were confirmed histologically by endoscopic or surgical resection, and their ultrasonographic images were compared with resection specimens.

RESULTS

Lipomas (n = 15) were visualized as hyperechoic masses and lymphangiomas (n = 9) visualized as cystic lesions with septal structures as characteristic findings. The EUS images of leiomyomas (n = 6), leiomyosarcomas (n = 3), and enteric endometriosis (n = 7) were all hypoechoic masses in the fourth layer. Leiomyosarcomas tended to be larger and more inhomogeneous than leiomyomas. Enteric endometriosis was shaped like a spindle or a half-moon, and myogenic tumors were lobulated when the lesions were large. Recurrences of colorectal carcinoma (n = 3), malignant lymphomas (n = 2), and an appendiceal mucocele (n = 1) were examined.

CONCLUSIONS

EUS is useful in the diagnosis of submucosal lesions of the large intestine because it provides precise information about these lesions.

Chromosomal mapping of genes in the RBCS family in Arabidopsis thaliana

In Arabidopsis thaliana, four genes have been identified in the RBCS gene family, one being assigned to subfamily RBCS-A and the other three to subfamily RBCS-B (1B, 2B and 3B). To determine the chromosomal location of these genes, hybridization analysis with CIC YAC high-density filters was carried out for the RBCS-A gene, and CAPS analysis for the three RBCS-B genes, based on the finding that restriction fragment length polymorphism is present in the upstream region of the gene RBCS-3B. The RBCS-A gene was mapped at 100.8 cM from the top of chromosome 1 and the three RBCS-B genes at 62.70 cM from the top of chromosome 5.

Relationship between local immune response to Helicobacter pylori and the diversity of disease: investigation of H. pylori-specific IgA in gastric juice

In order to evaluate the relationship between local immune response to Helicobacter pylori and the diversity of disease, 77 asymptomatic subjects who underwent a health examination were studied. Helicobacter pylori-specific IgG in serum and H. pylori-specific IgA in gastric juice were measured by ELISA, and the measured IgA titre was classified into two grades, low or high. Histological classification of gastritis was performed according to the Sydney system. Cytokines in gastric juice were also measured, and the cytotoxin-associated gene A (cagA) status of H. pylori was tested by PCR. Of the 65 subjects who were positive for H. pylori-specific IgG in serum, 38 (58.5%) were classified as H. pylori-specific IgA low titre in gastric juice and 27 (41.5%) had high titres. In the IgG-positive, IgA-low group, the rate of peptic ulcers (especially duodenal ulcers) in endoscopic findings was higher (P < 0.05); the score of activity and the density of H. pylori were higher (P < 0.001 and P < 0.05, respectively); the score of metaplasia was lower (P < 0.05); and the level of interleukin-1 beta was lower (P < 0.05) than in the IgG-positive, IgA-high group. The positive rate of the cagA gene was 84.4% and there was no significant difference between the two groups. There were differences in endoscopic and histological findings between the IgG-positive, IgA-low and the IgG-positive, IgA-high groups. It is suggested that persons infected with H. pylori can be divided into two different states of disease according to local immune response.

Three-dimensional endoscopic ultrasonography of gastrointestinal lesions using an ultrasound probe

BACKGROUND

This study was carried out to ascertain the clinical usefulness and problems of three-dimensional (3D) images obtained with the ultrasound probe.

METHODS

Eighteen resected specimens and 21 patients were examined. After the images were recorded on video, 3D displays were produced using a workstation.

RESULTS

In the in vitro study the surface images were quite consistent with the macroscopic findings in 17 cases. In 2 esophageal cancers, 7 of 10 gastric cancers, and 2 colonic cancers the depth of tumor invasion was assessed accurately from the reconstructed images. In the in vivo study although 3 D display had some limitations, it was useful in esophageal and rectal lesions.

CONCLUSIONS

This new diagnostic method could visualize the 3D extent of gastrointestinal lesions and appears to have a useful clinical application.

Histological evaluation of connective tissue components in the healing process of human gastric ulcer

1. The aim of the present study was the evaluation of human gastric ulcer healing and intractability from the viewpoint of connective tissue components. 2. Based on investigations of clinical status, we divided 78 patients with a gastric ulcer into three groups. All patients underwent gastrectomy and group I consisted of 17 patients operated on for bleeding or perforation, group II consisted of 37 patients operated on for an accompanying gastric carcinoma and group III consisted of 24 patients operated on for ulcer intractability. 3. We evaluated, in resected specimens, angiogenesis by Azan-Mallory staining and fibroplasia by applying proliferating cell nuclear antigen (PCNA) immunostaining. The inflammatory grade and fibrosis at the ulcer base were also evaluated by haematoxylin-eosin and Azan-Mallory staining. 4. Microvessel counts in group III were significantly lower than those in group I and II (P < 0.05). The PCNA labelling index of fibroblasts in group III was significantly lower than that in groups I and II (P < 0.05). The inflammatory grade was severe and fibrosis was excessive in group III. 5. From these results, it is suggested that the reduced angiogenesis and decline in fibrous cell proliferation are important factors contributing to gastric ulcer intractability.

Inhibition of tryptase TL2 from human T4+ lymphocytes and inhibition of HIV-1 replication in H9 cells by recombinant aprotinin and bikunin homologues

The serine esterase TL2 from human T4+ lymphocytes is a binding component to HIV-1 glycoprotein gp120 and seems to play a role in the HIV-1 infection mechanism. Recombinant variants of the Kunitz-type serine proteinase inhibitor aprotinin were investigated for their ability to inhibit tryptase TL2 and the binding of gp120 to this enzyme. Furthermore, the viral replication of HIV-1 was investigated H9 cell cultures under the influence of recombinant aprotinin and bikunin variants. In contrast to native aprotinin, the recombinant variant [Arg15, Phe17, Glu52] aprotinin with a reactive-site sequence homologous to the V3 loop of HIV-1 gp120 showed a specific inhibition of tryptase TL2 (> 80%). However, the [Leu15, Phe17, Glu52] aprotinin variant with hydrophobic subsites was the most potent inhibitor of the binding of gp120 to tryptase TL2 (68%). Our results show that the enzyme activity of purified tryptase TL2 is inhibited not only by variants with basic amino acids, but also those with hydrophobic residues in the reactive-site region. Therefore, tryptase TL2 is not a typical trypsin-like or chymotrypsin-like protease. Investigations on inhibition of HIV-1 replication in H9 cell cultures showed that tryptase TL2 is involved in the mechanism of virus internalization into human lymphocytes. The [Leu15, Phe17, Glu52] aprotinin showed a significant retardation of syncytium formation over a period of 5 days in a 1 micro M concentration. Similar investigations were performed with recombinant variants of bikunin, the light chain of human inter-alpha-trypsin inhibitor. Only the single-headed variant [Arg94] delta 2 bikunin inhibited slightly the syncytium formation over a period of 2 days in a 2.2 micro M concentration. Wild-type bikunin and all full-length variants showed no effect, possibly due to steric hindrance by the second domain of the double-headed inhibitor.

Evidence for transcriptional regulation of plastid photosynthesis genes in Arabidopsis thaliana roots

Mechanisms underlying suppressed levels of transcripts for plastid photosynthesis genes in nongreen tissues such as roots and calli were analyzed in Arabidopsis thaliana, a plant suitable for further genetic dissection. A region encoding promoters of rbcL, the gene encoding the large subunit of ribulose-1,5-biphosphate carboxylase/oxygenase, and the atpB/E operon for the beta and epsilon subunits of coupling factor one were cloned and sequenced. Transcripts for rbcL, atpB/E, and psbA, the gene for the D1 protein in the photosystem II reaction center, were barely detectable in roots of A. thaliana, whereas 16S rRNA was detected at a low level. The run-on transcription experiment revealed that expression of rbcL, atpB/E, and psbA was regulated at transcription. The copy number of plastid DNA in roots was one-fifth that in green leaves on the basis of total cellular DNA, suggesting that in the latter the DNA copy-number regulation also exists in plastid gene expression. Digestion of DNA with methyl-sensitive and -insensitive isoschizomeric endonucleases and subsequent polymerase chain reaction, as well as in vitro transcription of plastid DNAs with Escherichia coli RNA polymerase, resulted in no evidence of regulation by DNA modification. In spite of predominant suppression of expression of rbcL, atpB/E, and psbA at transcription in roots and calli, 16S rRNA levels were decreased because of low RNA stability.

Inhibitory effect of local anaesthetics on reactive oxygen species production by human neutrophils

BACKGROUND

Reactive oxygen species (ROS) generated from neutrophils accumulated in various major organs are thought to play a pivotal role in the pathogenesis of host auto-injury. Lidocaine has been shown to reduce the injury. We investigated the effect of local anaesthetics (lidocaine, mepivacaine and bupivacaine) on ROS production by neutrophils using an in vitro system.

METHODS

We measured the production of superoxide (ferricytochrome c method), hydrogen peroxide (H2O2: scopoletin fluorescence technique), and hydroxyl radical (OH.: ethylene gas method) by neutrophils isolated from human adult volunteers in the absence and presence of lidocaine (2-200 micrograms/mL), mepivacaine (3-300 micrograms/mL), and bupivacaine (3-300 micrograms/mL). We also measured the ROS generation in a cell-free (xanthine-xanthine oxidase) system.

RESULTS

Lidocaine and mepivacaine at higher levels significantly decreased the production of ROS by neutrophils. However, these local anaesthetics at clinically relevant blood concentrations had no effect on the levels of ROS. Furthermore, lidocaine and mepivacaine failed to reduce ROS generated by the cell-free system. Bupivacaine did not decrease ROS generation by either generating system.

CONCLUSION

In conclusion, in the present in vitro system, only concentrations of lidocaine and mepivacaine 100-fold higher than clinically feasible ones reduced ROS production by human neutrophils. However, the local anaesthetics at clinically relevant blood concentrations had no suppressive effect. Further studies using in vivo systems are required to elucidate the inhibitory effects of local anaesthetics on ROS generation in clinical settings.

[Trigeminal neuralgia caused by tortuous vertebrobasilar system--the clinical and imaging features]

Ten (6.8%) out of 146 patients with trigeminal neuralgia (TN) who underwent SPGR-MRI and 3D-TOF-MRA from August 1993 to October 1996, were found to have vascular compression caused by a tortuous vertebrobasilar system (TVBS). They were mostly males, demonstrated left-sided predominance, and had ipsilateral hemifacial spasm, compared with other 52 patients whose offending arteries were either superior cerebellar artery (SCA), anterior inferior cerebellar artery (AICA)or posterior inferior cerebellar artery (PICA). The patients who showed vascular compression by TVBS, presented an artery which compresses and dislocates the rootentry zone (REZ) of the trigeminal nerve, presses the brain stem at REZ and simultaneously compresses the REZ of the facial nerve. In addition, the diameters of the two branches of vertebrobasilar artery were not equal. These features indicate that the atherosclerotic change of the offending artery in TN caused by TVBS is more severe than that caused by SCA, AICA or PICA. This change causes an irregular running of artery which leads a strong compression of the trigeminal nerve REZ and of the brain stem. Consequently, the facial nerve REZ is severely affected leading to the presence of tic convulsif in TN caused by TVBS.

Preoperative staging of superficial esophageal carcinoma: comparison of an ultrasound probe and standard endoscopic ultrasonography

BACKGROUND

In diagnosing superficial esophageal carcinoma, it is necessary to differentiate mucosal carcinoma from submucosal carcinoma because mucosal carcinoma has a good prognosis and local treatment is likely to be successful. We evaluated an ultrasound probe and endoscopic ultrasonography (EUS) in the staging of superficial esophageal carcinoma.

METHODS

From October 1992 to September 1994, 22 patients with 25 lesions (7 mucosal carcinomas, 18 submucosal carcinomas) were examined preoperatively with both the probe and EUS. The ultrasound findings were compared with histologic findings in all cases.

RESULTS

The accuracy rates of the depth of invasion by the ultrasound probe were 86% (6 to 7) for mucosal carcinoma and 94% (17 to 18) for submucosal carcinoma, total 92% (23 to 25); by EUS 71% (5 to 7) for mucosal carcinoma and 78% (14 to 18) for submucosal carcinoma, total 76% (19 to 25). In the evaluation of lymph node metastasis, the overall accuracy was 56% by the ultrasound probe (sensitivity 25% and specificity 80%) and 67% by EUS (sensitivity 50% and specificity 80%).

CONCLUSIONS

The ultrasound probe was more convenient to use and more accurate than EUS in the evaluation of the depth of invasion of superficial esophageal carcinoma.

[Intraoperative assessment of mitral valve plasty by transesophageal echocardiography]

Mitral valve repair offers many advantages over prosthetic valve replacement, especially in minimizing the risk of thromboembolism. Intraoperative evaluation of residual mitral regurgitation (MR) is important in this procedure. The present study assessed the usefulness of transesophageal echocardiography (TEE) for the intraoperative assessment of residual MR in patients undergoing mitral valve repair. Intraoperative TEE was performed in 102 consecutive patients before and after mitral valve repair in the operating room. The grade of MR was evaluated according to the maximum MR jet area detected by biplane color Doppler TEE (mild: <4 cm2; moderate: 4 < or = < 7 cm2; severe : 7 cm2 < or =). After the first repair, the manual regurgitant test was performed. Excellent results with no or mild MR assessed by the manual regurgitant test were obtained in 101 patients. However, moderate or severe MR was identified in eight of these 101 (7.9%) patients by TEE after weaning from the cardiopulmonary bypass. Consequently, six of these eight patients underwent repeat mitral valve repair and two patients received prosthetic valve replacement. Satisfactory final operative results were obtained in all 101 patients. The eight patients who needed additional operative procedures followed good clinical courses in hospital. TEE 1 month after operation demonstrated no or mild MR in these eight patients. Intraoperative TEE is useful in the evaluation of residual MR after mitral valve repair. This technique provides indications for immediate additional operative procedures, and can reduce the occurrences of congestive heart failure and reoperation in the early stage after mitral valve repair.

Effect of pyridone carboxylic acid anti-microbials on the generation of reactive oxygen species in vitro

The effects of ofloxacin, ciprofloxacin and balofloxacin on the reactive oxygen species (ROS) levels generated by human neutrophils was examined in vitro; ROS generated in a cell-free, xanthine-xanthine oxidase system was also assessed. The species investigated were superoxide radical anion (O2-), hydrogen peroxide (H2O2) and hydroxyl radical (OH*). Both ofloxacin and ciprofloxacin markedly decreased the levels of O2-, H2O2 and OH* generated by human neutrophils. On the other hand, these drugs did not affect any of the ROS examined in the xanthine-xanthine oxidase system. Balofloxacin showed no significant effect on ROS generated by either system. The present study indicates that ofloxacin and ciprofloxacin may exert an anti-inflammatory action by reducing the potent ROS species excessively generated by neutrophils at the sites of inflammation.

Role of cytokines, tyrosine kinase, and protein kinase C on production of superoxide and induction of scavenging enzymes in human leukocytes

We investigated the effects of proximal modulators of cytokines, tyrosine kinase (TK), and protein kinase C (PKC) on reactive oxygen species (ROS) generation and the induction of scavenging enzymes, superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH-Px) of human neutrophils and lymphocytes, by using IL1-alpha, TNF-alpha, and IFN-gamma and neutralizing antibodies to these cytokines. Inhibitors of TK (ST638 and herbimycin) or PKC (H-7, calphostin, and staurosporine) were also used. The results revealed that both (O2)- generation stimulated by five different agents (opsonized zymosan, A23187, PAF, PMA, and fMLP) and the inductions of all three scavenging enzymes were potentiated by priming with TNF-alpha. In contrast, both (O2)- generation and enzyme induction were attenuated by priming with IL1-alpha, with the exception of PMA-stimulated (O2)- generation. IFN-gamma decreased (O2)- generation but increased scavenging enzyme induction. Antibodies to all three cytokines and all the TK and PKC inhibitors decreased (O2)- stimulated by most agents, but markedly enhanced (O2)- levels stimulated by PAF. Induction of all three enzymes was enhanced equally by low concentrations of each of the three anticytokine antibodies, while each of the TK or PKC inhibitors decreased induction of SOD and GSH-Px and increased catalase induction. These results suggest that both ROS generation and scavenging enzyme induction are controlled in complex ways by the actions of these three proximal mediators. This supports our hypothesis that disturbances in the regulation of early events of cell activation can lead to oxidative tissue injury.

Quantitation of alpha-fetoprotein and albumin messenger RNA in human hepatocellular carcinoma

To analyze gene expression of alpha-fetoprotein (AFP) and albumin in hepatocellular carcinoma (HCC), messenger RNAs (mRNAs) of these proteins in six human hepatoma cell lines and in 30 cases of HCC were quantitatively analyzed by competitive reverse transcription (RT) followed by polymerase chain reaction (PCR). The transcriptional levels of both AFP and albumin genes in HepG2 and Huh 7 cell lines were 10(10) copies/microgram RNA, in contrast to approximately 10(5) copies/microgram RNA in HLE and HLF cell lines. AFP and albumin mRNA levels in three normal livers were 10(5) and 10(10) transcripts/microgram RNA, respectively. In 30 cases with HCC AFP mRNA level in neoplasm was 10 to 10(5)-fold enhanced as compared with that of nonneoplastic portion, and correlated with serum AFP level and tumor size (P < .01). In contrast, albumin mRNA level was not reduced in the neoplasms presenting enhanced AFP mRNA levels, indicating that AFP and albumin gene expression in situ is not necessarily mutually exclusive. Prospective analysis revealed that an increased serum AFP was shown at the time of recurrence among patients with enhanced AFP mRNA levels in neoplasm only, indicating that AFP mRNA levels in neoplasm could be a clinically predictable tool.

[Percutaneous ethanol injection therapy for small hepatocellular carcinoma]

Hepatocellular carcinoma is different from other solid tumors. Because of concomitant cirrhosis or multiple lesions, most hepatocellular carcinoma is unresectable. Still worse, hepatocellular carcinoma frequently recurs after surgical resection; the 5-year cumulative recurrence rate is 70-90% even after curative hepatectomy. The situation is similar in small hepatocellular carcinoma 2 cm or less in diameter. Thus, non-surgical treatment plays an important role. At present, we think that percutaneous ethanol injection therapy (PEIT) is best for the treatment of hepatocellular carcinoma because of its local curativity, minimal adverse effect on liver function, and the easy feasibility of repeated treatment for recurrence. We have recently treated about 85% of hepatocellular carcinoma cases by PEIT and have achieved satisfactory long-term results. Here we describe our results in PEIT for small hepatocellular carcinoma. By the end of December 1995, we performed PEIT on 410 patients with hepatocellular carcinoma. Among them, 140 patients were diagnosed as having small hepatocellular carcinoma 2 cm or less in diameter. The 1-, 3-, 5-, 7-, and 10-year survival rates of the 140 patients were 93%, 73%, 55%, 51%, and 32%, respectively. Furthermore, in 83 patients who had a single, small hepatocellular carcinoma 2 cm or less in diameter, the 1-, 3-, 5-, 7-, and 10-year survival rates were 92%, 82%, 72%, 66%, and 66%, respectively. Thus PEIT achieved satisfactory long-term survival rates in the treatment of small hepatocellular carcinoma.

[Identification of offending vessels in trigeminal neuralgia and hemifacial spasm using SPGR-MRI and 3D-TOF-MRA]

We investigated 100 consecutive patients with trigeminal neuralgia (TN) and 53 patients with hemifacial spasm (HFS) concerning the anatomical relationship between the root entry (exit) zone (REZ) of cranial nerve and the offending artery, using spoiled GRASS MRI (SPGR-MRI) and three dimensional-time of fly-MRA (MRA). In 67 of 100 (67%) patiets with TN, this new radiological method, SPGR-MRI and MRA demonstrated the relationship between the fifth cranial nerve root and offending artery causing neurovascular compression (NVC), and in 46 of 53 (87%) with HFS, demonstrated the similar relationship between seventh and eighth nerve complex and offending artery. Microvascular decompression (MVD) was performed in 10 with HFS, and NVC of the REZ of the facial nerve caused by the offending artery was exactly predicted by SPGR-MRI and MRA in 9 (90%). The combination of SPGR-MRI and MRA is very useful for demonstrating NVC as the cause of TN and HFS. On the other hand, we investigated asymptomatic 206 trigeminal and 253 facial nerves about the relationship between their REZ and the surrounding structures using the similar method. The contact of REZ of cranial nerve with surrounding artery is demonstrated in 31.6% of trigeminal nerves and in 22.5% of facial nerves. These results indicate that the contact of REZ of cranial nerve with surrounding artery is not rare in healthy subjects, though causing TN and HFS in particular patients. In this context, we discussed the difference between the contact which is asymptomatic and the compression which is symptomatic.

T-cell membrane-associated serine protease, tryptase TL2, binds human immunodeficiency virus type 1 gp120 and cleaves the third-variable-domain loop of gp120. Neutralizing antibodies of human immunodeficiency virus type 1 inhibit cleavage of gp120

It has been suggested that the third variable domain (V3) loop of human immunodeficiency virus type 1 (HIV-1) gp120 has to interact with a cell-surface-associated protease(s) that acts as a cofactor after binding of gp120 to the CD4 receptor during entry of HIV-1 into susceptible cells. We isolated the membrane-associated serine protease, tryptase TL2, from human CD4-positive lymphocytes. This enzyme specifically binds gp120 through interaction with its V3 domain. To investigate the role of tryptase TL2 in HIV infection, we examined the affinity of the interaction and the proteolytic susceptibility of various recombinant gp120 expressed in mammalian cells to the enzyme, and we determined the cleavage sites. Tryptase TL2 bound gp120 with an apparent dissociation constant of 38 nM. The affinity was lower than that of gp120 for CD4 which suggests that gp120 initially binds to CD4, followed by interaction with tryptase TL2 which is localized close to CD4 on the cell surface. After binding, tryptase TL2 cleaved recombinant gp120 expressed in mammalian cells into two protein species of 70 kDa and 50 kDa but did not cleave gp120 expressed in insect cells, which indicates that the structure of the oligosaccharides linked to the polypeptide backbone of gp120 affects the proteolytic susceptibility. Cleavage was specifically inhibited by a neutralizing antibody against the V3 loop. Cleavage-site determination revealed that tryptase TL2 cleaved gp120 at various sites in the V3 in a strain-dependent manner. The amino acid variability at the cleavage site(s) in almost all HIV-1 isolates was restricted to amino acids which are susceptible to the chymotryptic and/or tryptic activities of tryptase TL2.

Enhanced effect of clarithromycin on neutrophil function in vitro

An in vitro study was carried out to investigate the effect of clarithromycin, a new oral macrolide, on neutrophil reactive oxygen species generation and chemotaxis. It was found that neutrophil-generated O2-, H2O2 and OH. levels were significantly increased by clarithromycin at concentrations of 50 micrograms/ml (P < 0.05). The drug also significantly increased chemotaxis (P < 0.05). These results indicate that clarithromycin may enhance the activation of neutrophils in vivo.

Engineered GFP as a vital reporter in plants

BACKGROUND

The green-fluorescent protein (GFP) of the jellyfish Aequorea victoria has recently been used as a universal reporter in a broad range of heterologous living cells and organisms. Although successful in some plant transient expression assays based on strong promoters or high copy number viral vectors, further improvement of expression efficiency and fluorescent intensity are required for GFP to be useful as a marker in intact plants. Here, we report that an extensively modified GFP is a versatile and sensitive reporter in a variety of living plant cells and in transgenic plants.

RESULTS

We show that a re-engineered GFP gene sequence, with the favored codons of highly expressed human proteins, gives 20-fold higher GFP expression in maize leaf cells than the original jellyfish GFP sequence. When combined with a mutation in the chromophore, the replacement of the serine at position 65 with a threonine, the new GFP sequence gives more than 100-fold brighter fluorescent signals upon excitation with 490 nm (blue) light, and swifter chromophore formation. We also show that this modified GFP has a broad use in various transient expression systems, and allows the easy detection of weak promoter activity, visualization of protein targeting into the nucleus and various plastids, and analysis of signal transduction pathways in living single cells and in transgenic plants.

CONCLUSIONS

The modified GFP is a simple and economical new tool for the direct visualization of promoter activities with a broad range of strength and cell specificity. It can be used to measure dynamic responses of signal transduction pathways, transfection efficiency, and subcellular localization of chimeric proteins, and should be suitable for many other applications in genetically modified living cells and tissues of higher plants. The data also suggest that the codon usage effect might be universal, allowing the design of recombinant proteins with high expression efficiency in evolutionarily distant species such as humans and maize.