Progressive interstitial renal fibrosis due to Chinese herbs in a patient with calcinosis Raynaud esophageal sclerodactyly telangiectasia (CREST) syndrome

A 58-year-old woman with calcinosis Raynaud esophageal sclerodactyly telangiectasia (CREST) syndrome presented with slowly progressive renal dysfunction. She was normotensive with normal plasma renin activity and lacking symptoms of vasculitis. Mild proteinuria was of tubular origin, but serological tests and an absence of sicca symptoms excluded the possibility of Sjögren's syndrome. Light microscopic study of renal biopsy showed interstitial fibrosis with ectasia and degeneration of proximal tubule and lymphocyte infiltration. There were no remarkable changes in the glomeruli. Chromatographic analysis of the Chinese herbs regimen that she had been taking for several years demonstrated aristolochic acid. She was diagnosed as Chinese herbs nephropathy. Therapy with oral prednisolone was markedly effective in improving renal function and anemia. To our knowledge, this is the first report of Chinese herbs nephropathy complicating connective tissue disease. It is important to consider the possibility of Chinese herbs nephropathy when patients treated with Chinese herbs develop renal dysfunction.

Clinical symptoms and surgical outcome in lumbar spinal stenosis patients with neuropathic bladder

We evaluated the clinical and radiologic features of patients with lumbar spinal stenosis with neuropathic bladder. Based on cystometrogram analysis, the patients were divided into two groups--the neuropathic bladder (NB) group: the NB+ group (23 patients), and the nonneuropathic bladder group: the NB- group (14 patients). The symptom of incontinence was characteristic in patients in the NB+ group. Patients in the NB+ group had a more severe neurologic disturbance, compared with those in the NB- group. The more severe neurologic disturbance was caused by the more striking finding of degenerative spinal stenosis associated with developmental narrowing of the spinal canal. Decompressive surgery had a beneficial effect on the recovery of the neurologic symptoms in both groups. Residual urine volume was reduced after surgery. Postoperative cystometrogram was carried out in nine patients in the NB+ group. It showed a normal pattern in six patients; however, three patients remained in an underactive pattern. Furthermore, four patients still required clear intermittent self-catheterization after surgery.

Distinct firing patterns of neuronal subtypes in cortical synchronized activities

Cortical neurons, especially GABAergic interneurons, are composed of very diverse subtypes. It remains to be investigated whether each subtype shows a unique firing pattern during the synchronized activities generated by the intracortical circuit. By lowering extracellular Mg(2+) in vitro, we induced NMDA receptor-dependent spontaneous activities in the rat frontal cortex at 30 degrees C. After a series of spontaneous depolarization shifts, the long bursts occurred. The long bursts were composed of initial discharges and fast run-like potentials (FRLP) (4-10 Hz). Large inhibitory currents were induced at the initial discharge. After the strong inhibition decreased, the FRLP started. However, the periodical inhibition survived during the FRLP. At each phase of the synchronized activities, cortical neuron types exhibited distinct firing patterns. Pyramidal cells increased firing frequency periodically up to approximately 25-55 Hz during the FRLP cycles. Fast-spiking (FS) cells fired at the highest frequency in the initial discharge, up to 400 Hz, and could continue firing faster than 200 Hz for several seconds. In the FRLP, the firing frequency of FS cells rhythmically increased up to 150 Hz. In contrast, large cholecystokinin basket cells fired, very similarly to pyramidal cells, at each phase. Somatostatin and vasoactive intestinal polypeptide cells fired faster than pyramidal cells at the initial discharge, but showed the similar firings to pyramidal cells during the FRLP. The firing patterns of cortical neurons are not only determined by the strength and temporal pattern of synchronized inputs but also strongly dependent on the neuronal subtype with specific physiological, chemical, and morphological characteristics.

Linearization and integration of DNA into cells preferentially occurs at intrinsically curved regions from human LINE-1 repetitive element

A bent DNA library was constructed from human genomic DNA, from which a new clone belonging to the human LINE-1 sequence family was isolated and characterized. This clone, with a length of 378 base pairs and termed HBC-1 (human bent clone-1), contained an intrinsically occurring curved DNA structure. By permutation analysis, the center of curvature of this fragment was mapped onto the nucleotide position 886 from the 5' terminus of the complete LINE-1 sequence. Reporter plasmids, which contain HBC-1, were effectively integrated into human chromosome, indicating that the bent DNA structure provides a preferential donor site for the integration of human LINE-1 sequences. The present finding may provide an explanation as to why some inactivated LINE-1 sequences on human chromosomes carry the deletion at their 5' termini.

Serial changes of herniated intervertebral discs after posterior lumbar discectomy: the relation between magnetic resonance imaging of the postoperative intervertebral discs and clinical outcome

To evaluate the relation between the morphologic changes of postoperative intervertebral discs and the clinical outcome after posterior lumbar discectomy, the size of the bulging disc was analyzed prospectively on serial follow-up magnetic resonance images in 26 randomly selected patients. The bulging of postoperative intervertebral discs involved three patterns of reduction: early reduction (n = 15), gradual reduction (n = 6), and late reduction (n = 5). There was a significant difference in the serial changes of subjective symptoms and neurologic function among the three patterns. A late reduction of postoperative disc bulging could cause late recovery of subjective symptoms and neurologic disturbance.

Mapping and promoter sequencing of HNF-1beta gene in diabetes-prone and -resistant mice

By using a novel single nucleotide polymorphism (SNP) in the coding sequence, the chromosomal location of Tcf2, encoding hepatic nuclear factor (HNF)-1beta, was determined in F2 intercrosses between Nagoya-Shibata-Yasuda (NSY) mice, an animal model of type 2 diabetes, and control C3H/He mice. The promoter region of Tcf2 gene was sequenced in NSY, non-obese diabetic (NOD) and control C3H/He mice. Tcf2 was mapped between genetic markers D11MIT320 and D11MIT195 with the following distances: D11MIT320-(7.3 cM)-Tcf2-(0.5 cM)-D11MIT195. A variant with insertion of C between -205 and -204 in the promoter region of Tcf2 was identified in NSY mice, but not NOD and C3H/He mice.

Tumor necrosis factor-alpha (TNF-alpha) converting enzyme contributes to production of TNF-alpha in synovial tissues from patients with rheumatoid arthritis

OBJECTIVE

Expression and function of tumor necrosis factor-alpha (TNF-alpha) converting enzyme (TACE) in synovia of patients with rheumatoid arthritis (RA) were examined to investigate posttranslational regulation of TNF-alpha production by TACE in RA.

METHODS

Expression of TACE protein was evaluated by immunohistochemistry. Cytokines and soluble cytokine receptors were measured by ELISA. TACE mRNA was detected by RT-PCR. The enzymatic activity of TACE was measured using TACE-specific fluorogenic substrate.

RESULTS

Expression of TACE at protein level in synovial tissue (ST) of patients with RA was significantly stronger than that of patients with osteoarthritis (OA). In RA, TACE was mainly expressed in CD68+ macrophage-like synovial cells. ST from 9 of 9 RA and 3 of 8 OA patients expressed TACE mRNA. RA ST cells possessed significantly higher TACE-like enzymatic activity than OA ST. A synthetic TACE inhibitor significantly reduced the release of TNF-alpha and p75 TNF receptor from RA ST cells.

CONCLUSION

TACE is an important regulator of the secretion of TNF-alpha from synovia of patients with RA.

Mature form of interleukin 18 is expressed in rheumatoid arthritis synovial tissue and contributes to interferon-gamma production by synovial T cells

OBJECTIVE

To investigate the expression and function of interleukin 18 (IL-18) in synovial tissue (ST) of patients with rheumatoid arthritis (RA).

METHODS

The localization of IL-18 in ST was analyzed by immunohistochemistry. IL-18 and IL-18 receptor (IL-18R) mRNA were detected by RT-PCR. Expression of IL-18 at the protein level was analyzed by Western blotting. Cytokines in culture supernatants were measured by ELISA.

RESULTS

From immunohistochemical analysis, IL-18-producing cells were localized in the lining layer and sublining region of RA ST. Most of them coexpressed CD68 antigen. In ST from patients with osteoarthritis (OA), IL-18-producing cells were localized only in the sublining region and the numbers of these cells were small. From RT-PCR, RA ST expressed mRNA of IL-18, as well as alpha- and beta-chains of IL-18R. OA ST did not express or very weakly expressed mRNA of alpha- and beta-chains of IL-18R. ST from RA patients produced significantly larger amounts of IL-18 in vitro than OA ST. Western blotting revealed that RA ST expressed mature IL-18 more abundantly than OA ST. IL-12 alone stimulates interferon-gamma (IFN-gamma) production by RA synovial tissue cells, but IL-18 alone could not. In the presence of IL-12, however, IL-18 could synergistically stimulate IFN-gamma production by RA synovial tissue cells. OA synovial tissue cells responded to neither IL-12 nor IL-12 + IL-18. IL-18 showed synergistic effects with IL-12 on promoting the ability of synovial T cells from RA patients to produce IFN-gamma.

CONCLUSION

These findings suggest that mature IL-18 is expressed in RA synovia and contributes to the production of IFN-gamma by infiltrating T cells.

Lack of association between hepatocyte nuclear factor-1beta gene and common forms of type 2 diabetes in the Japanese population

Mutations in the hepatocyte nuclear factor-1beta (HNF-1beta) gene have been shown to be a cause of maturity-onset diabetes of the young (MODY). We studied the contribution of the HNF-1beta gene to susceptibility to common forms of Type 2 diabetes in the genetically homogeneous Japanese population, by investigating the allelic association of Type 2 diabetes with two markers in the HNF-1beta region. The frequency of a nonsense mutation, R177X, which was previously reported in a Japanese family, was also studied by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method using a mismatch primer. A total of 200 subjects were studied. There was no significant difference in allele frequencies of either of the two polymorphisms studied between patients with Type 2 diabetes and control subjects, or between subgroups of patients subdivided by the presence of mild or severe diabetic nephropathy. None of the subjects studied had R177X mutation, giving a frequency of less than 1.1% in common forms of Type 2 diabetes in Japan. These results suggest that mutations in the HNF-1beta gene derived from a limited number of founders are not a major cause of common forms of Type 2 diabetes, even in the genetically homogeneous Japanese population.

Role of interaction between two silkworm RecA homologs in homologous DNA pairing

Recombinant BmRad51 and BmDmc1, silkworm homologs of the Escherichia coli RecA proteins catalyzing the homologous DNA pairing, were purified from E. coli cells carrying expression vectors. These possessed different enzymatic properties in the joint molecule formation between single-stranded circular DNA and homologous linear double-stranded DNA. The requirement of single-stranded circular DNA for the efficient reaction was twofold higher in BmRad51 than in BmDmc1. Although able to mediate the joint molecule formation independently, a complex of the two enzymes formed prior to single-stranded DNA binding was found to have augmented efficiency of the pairing reaction.

Successful gene therapy via intraarticular injection of adenovirus vector containing CTLA4IgG in a murine model of type II collagen-induced arthritis

We previously constructed an adenovirus vector carrying a gene encoding a soluble form of fusion protein, consisting of the extracellular portion of cytotoxic lymphocyte antigen 4 (CTLA4) and the Fc portion of human immunoglobulin G1 (Adex1CACTLA4IgG). Murine type II collagen-induced arthritis (CIA) was treated with Adex1CACTLA4IgG. A single intraarticular injection of 1 x 10(5) PFU was able to support serum CTLA4IgG at more than 10 microg/ml for at least 12 weeks and was able to inhibit the CIA clinically and histologically. In contrast, intravenous, intramuscular, or subcutaneous injection of 1 x 10(5) PFU was unable to support a significant level of serum CTLA4IgG and thus was unable to inhibit the development of arthritis. Thus, we demonstrated that (1) a low-dose intraarticular injection of Adex1CACTLA4IgG was effective in delaying the onset of CIA and reducing the severity of arthritis; (2) an intraarticular (knee joint) injection of Adex1CACTLA4IgG effectively blocked the development of arthritis in distal paws; (3) the inhibitory effect of Adex1CACTLA4IgG lasted at least up to 20 weeks; (4) although serum CTLA4IgG at more than 10 microg/ml persisted for at least 12 weeks, mice treated by intraarticular injection of Adex1CACTLA4IgG were not anergic to adenovirus and were able to mount antibody responses against various antigens.

Encapsulating peritoneal sclerosis: definition, etiology, diagnosis, and treatment. International Society for Peritoneal Dialysis Ad Hoc Committee on Ultrafiltration Management in Peritoneal Dialysis

Current definitions of encapsulating peritoneal sclerosis are practical and clinically relevant. It is important to adhere to a more uniform use of the proper terminology, and it is the recommendation of the authors that EPS be adopted as the more appropriate term. The best literal definition of EPS is based on clinical-pathologic criteria. Differentiation of EPS from the general category of ultrafiltration failure is required. Further, better appreciation of the diverse pathways that can lead to the same final common clinical-pathologic picture should not be overshadowed by the requirement of uniform terminology. Incidence and prevalence of the syndrome have been defined in some large populations and a few single-center experiences. The former show an incidence of less than 1%, while higher percentages are reported in the latter. The reported increased incidence with duration on therapy requires validation. The epidemiology of the syndrome offers limited insight into its pathogenesis. A list of factors, both dialysis-related and non dialysis-related. has been accumulated. Except in a few categories where agents are clearly related to the development of EPS, the majority of the listed factors for dialysis-related BPS remain, at best, associations and at worst, simple conjecture. The same limitations that plague the issue of etiology apply in the area of pathogenesis. More basic, focused work is required. The diagnosis of EPS remains based on clinical suspicion confirmed with, primarily, radiologic findings. Pathologic confirmation is obtained in cases that come to surgery for management or for catheter removal. Radiologic studies are precise enough for confirmation, but none have been evaluated for early diagnosis for possible early intervention or prevention. Studies based on transport characteristics or effluent dialysate constituents are not useful for EPS. At present, there are no reliable predictive tests for BPS that can be used in individual patients. Therapy of BPS is based on anecdotal evidence. The possible variable etiologies and probable distinct pathways leading to the syndrome may make a uniform therapeutic approach unlikely. Further, the limited number of cases and the sporadic pattern of occurrences make therapeutic trials not readily feasible. This is distinct from the case of ultrafiltration failure, where significant advances in mechanism elucidation and rationale-based interventions have been made.

[A case of recurrent hemophagocytic syndrome complicated with systemic sclerosis: relationship between disease activity and serum level of IL-18]

Hemophagocytic syndrome (HPS) is characterized by the activation of the mononuclear phagocytic system with prominent hemophagocytosis in the bone marrow and reticuloendothelial systems, and its occurrence is usually associated with variable disorders such as viral infections and malignant lymphoma. Recently, it was reported that HPS also occurred in association with underlying connective tissue disease, especially systemic lupus erythematosus. We report here a case of recurrent HPS complicated with systemic sclerosis. A 32-year-old woman had been diagnosed as systemic sclerosis since 1994. She was admitted due to unknown high fever and severe pancytopenia in 1997, and the diagnosis of HPS was determined because of hemophagocytosis in bone marrow and hyperferritinemia. Her symptoms were improved by immunosuppressive therapies including steroid pulse therapy and oral prednisolone (60 mg/day). She was followed by the treatment of oral prednisolone which was gradually tapered in our out-patient clinic. In August of 1999 high fever and severe anemia were recurred, and she was admitted again to our hospital because of the diagnosis as recurrent HPS. She had been treated with 40 mg/day of oral prednisolone and fever was immediately disappeared and hemoglobin was gradually increased. HPS is considered to be a rare complication with systemic sclerosis, and the etiology has been unknown. IL-18 is a novel cytokine which is a potent inducer of interferon-gamma, and its properties may be a proinflammatory regulation and activation of monocyte/macrophage and histiocyte through the expression of interferon-gamma. Therefore, the significance of IL-18 in the pathophysiology of HPS was recently reported. In this case, we investigated the significance of IL-18 and revealed the levels of serum IL-18 were well correlated with disease activity of HPS.

Identification of major phosphorylation sites of Epstein-Barr virus nuclear antigen leader protein (EBNA-LP): ability of EBNA-LP to induce latent membrane protein 1 cooperatively with EBNA-2 is regulated by phosphorylation

Epstein-Barr virus (EBV) nuclear antigen leader protein (EBNA-LP) is a phosphoprotein suggested to play important roles in EBV-induced immortalization of B cells. One of the potential functions of EBNA-LP is a cooperative induction with EBNA-2 of viral and cellular gene expression, including that of the genes for viral latent membrane protein 1 (LMP-1) and cellular cyclin D2. We report here that the phosphorylation of EBNA-LP by cellular kinase(s) is critical to its ability to cooperate with EBNA-2 in up-regulating the expression of LMP-1 in a B-lymphoma cell line. Our conclusion is based on the following observations. (i) Mass-spectrometric analysis of purified EBNA-LP and mutational analyses of EBNA-LP revealed that the serine residue at position 35 in the W2 repeat domain is the major phosphorylation site of EBNA-LP in vivo. (ii) Substitutions of this site in each W2 repeat domain with alanine markedly reduced the ability of the protein to induce LMP-1 expression in combination with EBNA-2 in Akata cells. (iii) Replacement at the major phosphorylation sites with glutamic acids restored the wild-type phenotype. It is well established that this substitution mimics constitutive phosphorylation. These results indicated that the coactivator function of EBNA-LP is regulated by phosphorylation.

Effects of 5-fluorouracil on the drug-metabolizing enzymes of the small intestine and the consequent drug interaction with nifedipine in rats

5-Fluorouracil (5-FU) is a widely used antineoplastic agent. 5-FU therapy often causes gastrointestinal toxicity, which is suppressed by concomitant administration of potassium oxonate (Oxo). Here, we investigated the effect of 5-FU on the small-intestinal drug-metabolizing enzymes, which play important roles in the first-pass metabolism of drugs, in rats, by enzyme measurements and immunoblot analyses. During repeated administration of a combination of 1-(2-tetrahydrofuryl)-5-fluorouracil, an oral 5-FU-derivative drug, and 5-chloro-2,4-dihydroxypyridine (FCD), an inhibitor of 5-FU degradation, the activities of 7-ethoxyresorufin-O-deethylase, testosterone 6beta-hydroxylase, 4-methylumbelliferone UDP-glucuronyltransferase, and 1-chloro-2,4-dinitrobenzene glutathione S-transferase decreased significantly on day 4, and the activity of NADPH-cytochrome P450 (CYP) reductase decreased significantly on day 7. These effects were found to be attributable to a reduction in the enzyme protein contents in the small-intestinal mucosa. The enzymatic alterations significantly increased the plasma concentrations of orally administered nifedipine, which was prevented by concomitant administration of Oxo with FCD. However, consecutive administration of FCD for 4 days did not cause any alterations in the activity of the hepatic CYP isozyme-supported testosterone hydroxylase. These results suggest that continuous exposure to 5-FU leads to a decrease in the activities of drug-metabolizing enzymes in the intestinal mucosa by decreasing their enzyme protein contents, and increases the plasma concentrations of orally administered nifedipine, and that the sensitivity of these enzymes to the drug is greater than that of the enzymes of the liver. These effects were prevented by concomitant administration of Oxo.

Kit(+) melanocytes seem to contribute to melanocyte proliferation after UV exposure as precursor cells

Melanogenesis caused by UV exposure is characterized by proliferation and differentiation of functioning melanocytes in epidermis. Recently, the existence of precursor melanocytes in normal skin was proposed immunohistochemically. Thus, this precursor melanocyte seems to proliferate and differentiate into mature pigmented melanocytes after UV exposure. To elucidate how these processes occur, we examined C57BL mouse epidermal sheets after UV exposure immunohistochemically. In normal epidermis, TRP-1(+) cells and Kit(+) cells were easily identified and the cellularities were 41.0 and 31.7 cells per mm(2), respectively. Only a few Mitf(+) cells and no TRP-2(+) cells were observed. On the first day after UV exposure, Mitf(+) cells and TRP-2(+) cells appeared, whereas the numbers of TRP-1(+) cells and Kit(+) cells decreased. Some Kit+ cells also expressed Mitf, but no TRP-1 and Mitf double positive cells were seen. In this period, some Mitf(+) cells were labeled with BrdU. The next day, Mitf(+) cells and TRP-2(+) cells increased to the maximum cellularity, and they decreased thereafter and disappeared on the seventh day. An increase of TRP-1(+) cells was first identified on the fifth day after UV exposure, and reached a cellularity four times as great as that of the normal control on the fourteenth day. The subepidermal injection of Kit antibody attenuated the increase of Mitf+ cells and TRP-1(+) cells. These findings suggested that precursor cells that reside in the skin, first differentiated into Mitf(+) and TRP-2(+) melanocytes by the activation of the Kit receptor, then become mature TRP-1(+) melanocytes after UV exposure.

CD40-CD40 ligand (CD154) engagement is required but not sufficient for modulating MHC class I, ICAM-1 and Fas expression and proliferation of human non-small cell lung tumors

To determine the possible functional significance of CD40 expression on human non-small cell lung carcinomas and to assess the potential of CD40 as a therapeutic target, 18 lung tumor cell lines were established from biopsy tissues and were monitored for phenotypic changes on the cell surface and alterations in tumor cell proliferation after the ligation of CD40 with a trimeric fusion protein complex of CD40 ligand (CD40Lt). CD40 cross-linking resulted in up to a 6-fold increase in the surface expression of major histocompatibility complex (MHC) class I, Fas and intracellular adhesion molecule (ICAM)-1 in a subset of tumors expressing the highest levels of CD40. Suppression of tumor proliferation was seen after the ligation of CD40 on CD40Lt-responsive cell lines. The suppression was dose dependent, reversible and resulted from a delay of the tumor cells entering S-phase. No change in the cell phenotype or in proliferation were observed in CD40-negative tumors or in tumors expressing moderate-to-low levels of CD40 after incubation with CD40Lt. CD40-negative tumors transfected with the CD40 gene expressed high levels of CD40 on their surface, but were also unresponsive to CD40Lt cross-linking of CD40. Our data establish that CD40 is required (but not sufficient) for transducing a signal that results in phenotypic changes in human lung tumors and suppression in their proliferation. We conclude that CD40 on non-small cell lung tumors may represent a potential therapeutic target, but only on a subset of the CD40+ tumors.

Image-guided anterior thoracolumbar corpectomy: a report of three cases

STUDY DESIGN

A report of three cases of thoracolumbar vertebral collapse treated with image-guided anterior corpectomy.

OBJECTIVES

To document the surgical technique and the usefulness of image-guided anterior corpectomy for thoracolumbar vertebral collapse.

SUMMARY OF BACKGROUND DATA

Computer-assisted navigation systems can provide accurate three-dimensional surgical information intraoperatively. However, there is no clinical report regarding the application and usefulness of the computer-assisted navigation system for anterior thoracolumbar corpectomy.

METHODS

After exposure of anterior and lateral aspects of the vertebral bodies through the transpleural approach, a reference frame was fixed to the thoracolumbar spinous process. Then thoracolumbar corpectomy and decompression were carried out under computer assistance.

RESULTS

The tip of the standard probe and the angled rongeur could be monitored on three-dimensional images during surgery, and the retropulsed fragments within the spinal canal could be safely and completely removed under computer assistance.

CONCLUSION

This image-guided procedure would aid surgeons in the complete and safe decompression of thoracolumbar injury.

Polymorphism in gene for islet autoantigen, IA-2, and type 1 diabetes in Japanese subjects

Autoantibodies against IA-2 have been detected in up to 86% of newly diagnosed patients with type 1 diabetes and appear to identify a subgroup of prediabetic subjects who rapidly progress to type 1 diabetes. We examined the association of IA-2 gene polymorphism with type 1 diabetes in Japanese subjects. A total of 276 Japanese subjects were studied for disease association and, in addition, another 53 patients were studied for association with the autoantibody status to IA-2. A microsatellite marker D2S1753E, located in the intron of the IA-2 gene, was used as a genetic marker in this study. In Japanese, two alleles (161mu and 165mu) were more frequent, and the 163mu allele was less frequent than in Caucasians (p = 0.0001). There was no significant difference in frequencies of alleles between diabetic patients and control subjects. The frequency of IA-2 gene polymorphism was not significantly different between patients stratified by age-at-onset, or between patients with and without susceptible HLA, DRB1*0405, DRB1*0802 and DRB1*0901. There was no significant difference in allele frequency of the IA-2 gene polymorphism between patients with and without autoantibody to IA-2. In conclusion, IA-2 gene polymorphism is not associated with either susceptibility to, or heterogeneity in type 1 diabetes in Japanese subjects.

Effect of a selective Abl tyrosine kinase inhibitor, STI571, on in vitro growth of BCR-ABL-positive acute lymphoblastic leukemia cells

By employing a new semi-quantitative assay system that includes co-culturing leukemia cells with the mouse bone marrow-derived stromal cell line MS-5, we examined the suppressive effect of a selective inhibitor of ABL tyrosine kinase, STI571, on acute lymphoblastic leukemia (ALL) cells with BCR-ABL fusion. Leukemic blast cells from eight patients with B-precursor ALL, including three patients with BCR-ABL-positive ALL, were cultured on monolayers of MS-5 cells for 3 weeks with or without addition of variable amounts of STI571. In all cases, cobblestone areas (CAs) were formed, showing clear linear cell dose-dependent curves, allowing quantitative assessment of blast cell growth. The progenitor frequencies obtained by this direct CA-forming cell (CAFC) assay were equivalent to ALL progenitor frequencies assessed by the standard limiting dilution assay. The number of CAFCs ranged from 12.3 to 140.3/10(4) cells. In BCR-ABL-positive ALL patients, CA-containing cells were examined by FISH, and all contained BCR-ABL fusion genes. STI571 inhibited CA formation of BCR-ABL-positive ALL cells virtually 100% at 0.1-1.0 micromol/l. None of the five BCR-ABL-negative ALL patients showed this growth inhibition by STI571 at 0.1-1.0 micromol/l. Our results indicate that STI571 selectively inhibits in vitro growth of BCR-ABL-positive ALL cells.

Improvement in precision of the liquid chromatographic-electrospray ionization tandem mass spectrometric analysis of 3'-C-ethynylcytidine in rat plasma

During the development of the liquid chromatography with electrospray ionization-tandem mass spectrometry for the quantitative determination of 3'-C-ethynylcytidine (I) in rat plasma, ion suppression caused by the matrix components was observed for I and its structural analogue, 3'-C-ethylcytidine (II) as the internal standard. In the method initially designed, I/II peak area ratios varied according to the degree of matrix effect, which led to the poor precision of the assay. From the examination of the ion suppression behavior for I and II, it was assumed that this phenomenon is attributed to the difference in the retention time between I and II. Based on this assumption, therefore, the methanol content in the mobile phase was changed from 5 to 25% so as to make I and II the same retention time. As a result of this modification of the initial method, the precision expressed as relative standard deviation was improved from 5.2-16.2 to 2.7-4.2% in intra-assay and from 6.8-14.9 to 3.5-7.2% in inter-assay validations.

Minimum 10-year follow-up study of anterior lumbar interbody fusion for isthmic spondylolisthesis

The aims of the current study were to evaluate the long-term clinical and radiologic results of anterior lumbar interbody fusion (ALIF) for isthmic spondylolisthesis. Between 1981 and 1988, a total of 35 patients underwent ALIF for isthmic spondylolisthesis. Of these, 23 patients were followed clinically and radiographically for more than 10 years (average, 13.3 years). The Japanese Orthopaedic Association low-back pain score was used to evaluate the outcome of subjective symptoms and clinical signs. The preoperative and postoperative percentage of slip, preoperative and postoperative intervertebral disk height, interbody graft union, and pars defect union were evaluated by serial radiographs. The adjacent disk degeneration was also evaluated by radiographs and magnetic resonance imaging. Although the low-back pain score worsened after 5 years, ALIF provides satisfactory overall long-term clinical results. The preoperative percentage of slip and the disk height were corrected after surgery, but at the time of interbody graft union, slip and disk height recurred as a result of grafted bone collapse. The rate of union in the grafted area was 83%. In the nonunion cases, the scores gradually deteriorated with time, but the overall results were not different from those of union cases. Radiographs showed adjacent disk degeneration in 52% of cases in the upper adjacent level and in 70% of cases in the lower adjacent level, but these changes were not correlated with clinical outcomes.

The Pro12 -->Ala substitution in PPAR-gamma is associated with resistance to development of diabetes in the general population: possible involvement in impairment of insulin secretion in individuals with type 2 diabetes

The allele frequencies for a Pro12-->Ala substitution in peroxisome proliferator-activated receptor-gamma differ among ethnic groups, and its relationship with diabetes and associated diseases is controversial. The prevalence of this polymorphism and its effects on clinical characteristics have now been evaluated with a large number of Japanese individuals with type 2 diabetes (n = 2,201) and normal control subjects (n = 1,212) recruited by 10 institutions located in seven different cities in Japan. The allele frequency for the Ala12 variant was significantly lower in the type 2 diabetic group than in the control group (2.39 vs. 4.13%, P = 0.000054). However, compared with subjects without the Ala12 variant, the diabetic subjects with this variant exhibited a significantly higher serum concentration of total cholesterol (P = 0.001), manifested a reduced capacity for insulin secretion as evaluated by homeostasis model assessment (P = 0.007), and tended to possess a higher level of HbA1c. These data suggest that the Ala12 variant is associated with a reduced risk for the development of diabetes in the general population, but that it may be also a risk factor for insulin deficiency and disease severity in individuals with type 2 diabetes.

Decreases in phenytoin hydroxylation activities catalyzed by liver microsomal cytochrome P450 enzymes in phenytoin-treated rats

Phenytoin, 5,5-diphenylhydantoin, is a widely used anticonvulsant agent with a variety of toxicities, including drug interactions. The formation of four oxidative metabolites, 4'-hydroxylated (4'-HPPH), 3'-hydroxylated (3'-HPPH), a catechol (3',4'-diHPPH), and the 3',4'-dihydrodiol form of phenytoin was examined in rat liver microsomes. In 11 cDNA-expressed rat P450 enzymes tested, CYP2C6 had the highest activities in 4'- and 3'-HPPH formation from phenytoin, followed only by CYP2C11. In contrast, CYP2C11 had high activity for 3',4'-diHPPH formation from 4'-HPPH, followed by CYP2C6. The rates of 4'-HPPH and 3',4'-diHPPH formation from phenytoin in liver microsomes in the presence of NADPH were significantly decreased by oral administration of phenytoin (300 mg/kg for 20 days) to rats, despite the increase in P450 contents. However, the cumene hydroperoxide-supported formation of 3',4'-dihydrodiol and 4'-HPPH from phenytoin was induced by phenytoin administration. Hydrogen peroxide formation in reaction mixtures with NADPH was induced by the administration of phenytoin; however, the coupling ratio of phenytoin oxidation was decreased in phenytoin-induced liver microsomal P450 systems. These results suggested that phenytoin could not stimulate its own apparent oxidative metabolism by liver P450s induced with phenytoin administration. The increase of unmetabolized phenytoin and byproducts of oxygen generated in the phenytoin-induced liver microsomal P450 system may be involved in phenytoin-related drug toxicity.

Sequence analysis of candidate genes for common susceptibility to type 1 and type 2 diabetes in mice

Although type 1 and type 2 diabetes are regarded as clinically distinct diseases, several lines of evidence have suggested common genetic factors between the two types of diabetes. The non-obese diabetic (NOD) mouse, an animal model of type 1 diabetes, and the Nagoya-Shibata-Yasuda (NSY) mouse, a model of type 2 diabetes, are derived from the same outbred colony, Jcl:HCR, suggesting a shared susceptibility between the two types of diabetes in mice. Genetic as well as functional studies have supported the possibility that Tcf2, which encodes the transcription factor, hepatocyte nuclear factor 1beta (HNF-1beta), is a candidate gene for the common susceptibility between NSY and NOD mice. Txn, encoding thioredoxin which is a redox (reduction/oxidation)-active protein, is also a positional and functional candidate for a common susceptibility gene. To investigate whether either of these two genes is a common susceptibility gene, the coding nucleotide sequences of these two genes were compared among the NSY, NOD and control C3H strains. The coding sequence of Tcf2 of the NOD mouse was identical to that of the C3H mouse, but was different from that of the NSY mouse. The coding sequence of Txn was identical in the three strains. These data suggest that neither of the two genes is a common susceptiblity gene between type 1 and type 2 diabetes in mice.

Clinical features of extraforaminal lumbar disc herniation based on the radiographic location of the dorsal root ganglion

STUDY DESIGN

The relations between the location of the dorsal root ganglion and pre- and postoperative symptoms were reviewed retrospectively in 27 patients who underwent radiculography and posterior discectomy.

OBJECTIVES

To evaluate the clinical features and surgical outcome of extraforaminal lumbar disc herniation based on the location of dorsal root ganglion.

SUMMARY OF BACKGROUND DATA

The location of dorsal root ganglia has been reported to be correlated with a variety of radicular symptoms. Extraforaminal lumbar disc herniation has several specific clinical features, one of which is severe radicular pain. However, there is no report in the literature on the association between the location of the dorsal root ganglia and the severity of the symptoms of extraforaminal lumbar disc herniation.

METHODS

The radiographic location of the dorsal root ganglion of each compressed nerve root was determined by preoperative direct radiculograms. All patients were classified into the following three groups according to the location of dorsal root ganglion: intraspinal, intraforaminal, and extraforaminal. The incidences of these locations were 5 of 27 (18.5%), 15 of 27 (55.5%), and 7 of 27 (25.9%), respectively. The relation between the location of the dorsal root ganglion and clinical parameters such as the level of the compressed nerve root, the degree of limitation on straight leg raising test, the severity of the pre- and postoperative subjective symptoms (leg pain, low back pain, and walking capacity), clinical signs (sensory and motor disturbance), and the recovery rate were investigated.

RESULTS

The degree of limitation on the straight leg raising test in the extraforaminal group tended to be low, compared with that in the intraspinal and intraforaminal groups. Low back pain in the extraforaminal group was more severe than that in the intraspinal and intraforaminal groups. Preoperative leg pain in the extraforaminal group was significantly more severe that that in the intraspinal group, and the walking capacity in the extraforaminal group tended to be lower than that in the intraspinal and intraforaminal groups. No significant differences were found between the location of dorsal root ganglion and the preoperative sensory or motor disturbance and surgical outcomes.

CONCLUSION

The location of the dorsal root ganglion might influence the severity of radicular symptoms (pain and walking distance tolerance) in patients with extraforaminal lumbar disc herniation.

Involvement of microsomal cytochrome P450 and cytosolic thymidine phosphorylase in 5-fluorouracil formation from tegafur in human liver

Recently, we have reported that tegafur, an anticancer agent, is biotransformed into active drug 5-fluorouracil (5-FU) by cytochromes P450 1A2, 2A6, and 2C8 in human liver microsomes (T. Komatsu et al., Drug Metab. Dispos, 28: 1457-1463, 2000). Because the conversion of tegafur into 5-FU has also been reported to be catalyzed by cytosolic thymidine phosphorylase (dThdPase), the involvement of human liver microsomes and cytosol and individual differences in 5-FU formation from tegafur were investigated. In 14 human samples, the mean rates of 5-FU formation in liver microsomes were 5-fold and 2-fold higher than those in liver cytosol at substrate concentrations of 100 microM and 1 mM tegafur, respectively. In the presence of 5-chloro-2,4-dihydroxypyridine, a dihydropyrimidine dehydrogenase inhibitor, the rates of 5-FU formation by the combination of liver microsomes and cytosol showed 5- and 3-fold interindividual differences at 100 microM and 1 mM tegafur, respectively. Kinetic analysis of human liver cytosolic 5-FU formation indicated an apparent higher Km value (16 +/- 4 mM) than that of liver microsomes (1.8 +/- 0.3 mM) with similar Vmax values. Human liver cytosolic 5-FU formation was confirmed to be catalyzed by dThdPase with correlation and chemical inhibition studies. These results suggested that 5-FU formation from tegafur in human liver was mainly catalyzed by microsomal P450 at low concentrations of tegafur, but the contribution of cytosolic 5-FU formation by dThdPase would be important at high concentrations.

Herpes simplex virus 1 alpha regulatory protein ICP0 functionally interacts with cellular transcription factor BMAL1

The infected cell protein no. 0 (ICP0) of herpes simplex virus 1 (HSV-1) is a promiscuous transactivator shown to enhance the expression of gene introduced into cells by infection or transfection. At the molecular level, ICP0 is a 775-aa ring finger protein localized initially in the nucleus and late in infection in the cytoplasm and mediates the degradation of several proteins and stabilization of others. None of the known functions at the molecular level account for the apparent activity of ICP0 as a transactivator. Here we report that ICP0 functionally interacts with cellular transcription factor BMAL1, a member of the basic helix-loop-helix PER-ARNT-SIM (PAS) super family of transcriptional regulators. Specifically, sequences mapped to the exon II of ICP0 interacted with BMAL1 in the yeast two-hybrid system and in reciprocal pull-down experiments in vitro. Moreover, the enhancement of transcription of a luciferase reporter construct whose promoter contained multiple BMAL1-binding sites by ICP0 and BMAL1 was significantly greater than that observed by ICP0 or BMAL1 alone. Although the level of BMAL1 present in nuclei of infected cells remained unchanged between 3 and 8 h after infection, the level of cytoplasmic BMAL1 was reduced at 8 h after infection. The reduction of cytoplasmic BMAL1 was significantly greater in cells infected with the ICP0-null mutant than in the wild-type virus-infected cells, suggesting that ICP0 mediates partial stabilization of the protein. These results indicate that ICP0 interacts physically and functionally with at least one cellular transcription-regulatory factor.

Change of muscle motor-evoked potentials after motor cortex stimulation caused by acute spinal cord injury in cats

The validity of the evoked compound muscle action potential (ECMAP) as an index of spinal cord injury has not been established in neurophysiologic monitoring of motor function, although evoked spinal cord potential (ESCP) has been. In the current study, nine cats were used. After craniotomy, electric stimuli were applied to the motor area. Four cats were given stimulation of various numbers and frequencies, and the other five cats underwent graded compression of the spinal cord, and then ECMAPs and ESCPs were recorded. Three cats were awakened and their motor functions were assessed 3 weeks later. The amplitude of the ESCP never decreased to 60% or less of the control value, even when ECMAPs disappeared. No motor dysfunction was present 3 weeks after the experiment. ECMAP is clinically useful, providing information on impairments of the spinal cord that otherwise would remain undetected.

Variants of neurogenin 3 gene are not associated with Type II diabetes in Japanese subjects

AIMS/HYPOTHESIS

Neurogenin 3 (ngn3) is a transcription factor expressed in the endocrine precursor cells of the pancreas. It has recently been reported that ngn3-deficient mice show absence of pancreatic endocrine cells and die of postnatal diabetes. The purpose of this investigation was to screen for polymorphisms of the ngn3 gene and to test whether these polymorphisms are associated with Type II (non-insulin-dependent) diabetes mellitus in the Japanese subjects.

METHODS

We screened ngn3 gene and upstream region by direct sequencing and estimated the prevalence of polymorphisms in 197 patients with Type II (non-insulin-dependent) diabetes mellitus and 216 control subjects.

RESULTS

We identified four novel polymorphisms, Ser199Phe (596C/T), -43insCA, -983C/T and -1822G/A. In an association study the allelic frequencies of the major allele of these four polymorphisms were 0.721, 0.914, 0.912 and 0.530 in diabetic patients, respectively, and 0.694, 0.905, 0.917 and 0.537 in control subjects, respectively.

CONCLUSION/INTERPRETATION

Mutations and polymorphisms of ngn3 gene are not significantly associated with Type II (non-insulin-dependent) diabetes mellitus in the Japanese subjects.

The conserved domain CR2 of Epstein-Barr virus nuclear antigen leader protein is responsible not only for nuclear matrix association but also for nuclear localization

There is a growing body of evidence for the importance of the nuclear matrix in various nuclear events including gene expression and DNA replication. Epstein-Barr virus (EBV) nuclear antigen leader protein (EBNA-LP) is a nuclear matrix-associated protein that has been suggested to play an important role in EBV-induced transformation. To define the biological significance of the association of EBNA-LP with the nuclear matrix, we mapped the domain of EBNA-LP responsible for nuclear matrix association and investigated the functions of the EBNA-LP mutant mutagenized by substitution of alanines for the cluster of arginine residues in the mapped region. The results of the present study were as follows. (i) Transiently expressed EBNA-LP in COS-7 or BOSC23 cells was associated with the nuclear matrix, similarly to that in EBV-infected B cells. (ii) Mutational analysis of EBNA-LP revealed that a 10-amino acid segment of EBNA-LP is critical for nuclear matrix association of the protein. Interestingly, the identified region overlapped with the region CR2 of EBNA-LP conserved among a subset of primate gammaherpesviruses. The identified segment is referred to as EBNA-LP NMTS (nuclear matrix targeting signal). (iii) The EBNA-LP mutant with the arginine to alanine substitutions in NMTS was no longer localized not only to the nuclear matrix but also to the nucleus. (iv) The EBNA-LP mutant lacked its ability to coactivate EBNA-2-dependent transactivation. These results indicated that EBNA-LP needs to be localized in the nucleus and/or associated with the nuclear matrix through CR2 to elicit its function such as the coactivation of the EBNA-2-dependent transcriptional activation.

Human inflammatory cells within the tumor microenvironment of lung tumor xenografts mediate tumor growth suppression in situ that depends on and is augmented by interleukin-12

The human tumor microenvironment includes a mixture of tumor cells, inflammatory cells, fibroblasts, and endothelial cells, all of which are tethered to an extracellular matrix. It has been difficult to study the dynamic interactions of these cells in human tumors in situ for obvious ethical and logistical considerations that prohibit experimental manipulations of tumors while still in patients. Fresh tissue from human lung tumor biopsy implanted into SCID mice was shown to remain viable, and the histologic appearance of the tumor microenvironment was maintained in the tumor xenografts for at least 3 months. In this study, the authors established that the inflammatory cells within human tumor xenografts can suppress tumor growth, and that this suppression is a result, in part, of endogenously produced interleukin-12 (IL-12) because IL-12 neutralizing antibodies enhance the growth of the tumor xenografts. The tumor-inhibitory activity of the inflammatory leukocytes is also enhanced by the local and sustained release of human recombinant IL-12 into the tumor microenvironment from cytokine-loaded biodegradable microspheres. Neither the anti-IL-12 neutralizing antibody nor the delivery of exogenous IL-12 from microspheres had any effect on tumor xenografts in the absence of the inflammatory leukocytes. In conclusion, the inflammatory cells within the tumor microenvironment of human lung tumor xenografts are functional and can suppress tumor growth, and the dynamic effects of the inflammatory cells can be modulated by exogenous cytokines.

[Questionnaire on "having a family dentist" and the status of oral health]

In 1999, we gave a Questionnaire on "having a family dentist" to 414 workers (300 males, 114 females) at a government office. Oral health examination was also provided to the same subjects. The following results were obtained: 1. Female workers (43%) had a family dentist more often than male workers (29%), and the difference was significant (p < 0.01). 2. About 45% of the subjects received regular dental checkups at least once a year; however, half of them did not have a family dentist. 3. Convenience, comfort, and communication factors were the main reasons for choosing a particular dentist, while continuity, comprehensiveness, and specialty factors were not taken into consideration in choosing a dentist. 4. The persons who had family dentists had more FT and DMFT, and fewer total numbers of teeth than those without family dentists. From these results, it was suggested that people visited dentists with dental problems and received treatment repeatedly, and then they came to have family dentists. The habit of visiting a dentist regularly seeking checkups and prevention is not yet popular among Japanese adults. To improve oral health consciousness and to promote oral health, it should be recommended to receive regular checkups and oral health education by a family dentist. However, the present condition does not allow this system. Therefore in Japan, it should be encouraged to provide oral health examination and oral health education regularly at work sites, to improve the oral health of the adult population.

Bioactivation of tegafur to 5-fluorouracil is catalyzed by cytochrome P-450 2A6 in human liver microsomes in vitro

Tegafur is a prodrug of 5-fluorouracil (5-FU) consisting of a new class of oral chemotherapeutic agents, tegafur/uracil and S-1, which are classified as dihydropyrimidine dehydrogenase inhibitory fluoropyrimidines. It is bioactivated to 5-FU via 5'-hydroxylation mediated by cytochrome P-450 (CYP). However, which isoform(s) of CYP is responsible for the bioactivation process of tegafur remains unclear. The purpose of the present study was to identify the human CYP isoform(s) involved in the metabolic activation of tegafur using human liver microsomes and cDNA-expressed human CYPs. The formation of 5-FU from tegafur in human liver microsomes showed biphase kinetics with Km and Vmax values for the high-affinity component of 0.43 +/- 0.05 mM and 4.02 +/- 1.70 nmol/mg/min (mean +/- SD, n = 4), respectively. In the correlation study using a panel of 10 human liver microsomes, the formation of 5-FU from tegafur showed a significant correlation (r = 0.98; P < 0.001) with coumarin 7-hydroxylation, a marker activity of CYP2A6. In addition, a specific substrate of CYP2A6 and anti-CYP2A6 antibody inhibited the formation of 5-FU by 90% in human liver microsomes. Moreover, cDNA-expressed CYP2A6 showed the highest activity for the formation of 5-FU among 10 cDNA-expressed CYPs, with a Km value similar to that found for the high-affinity component in human liver microsomes. These findings clearly suggest that CYP2A6 is a principal enzyme responsible for the bioactivation process of tegafur in human liver microsomes. However, to what extent the bioactivation of tegafur by CYP2A6 accounts for the formation of 5-FU in vivo remains unclear, because the formation of 5-FU from tegafur is also catalyzed by the soluble fraction of a 100,000 x g supernatant and also derived from spontaneous degradation of tegafur.

Interaction of Epstein-Barr virus nuclear antigen leader protein (EBNA-LP) with HS1-associated protein X-1: implication of cytoplasmic function of EBNA-LP

Epstein-Barr virus (EBV) nuclear antigen leader protein (EBNA-LP) consists of W1W2 repeats and a unique C-terminal Y1Y2 domain and has been suggested to play an important role in EBV-induced transformation. To identify the cellular factors interacting with EBNA-LP, we performed a yeast two-hybrid screen, using EBNA-LP cDNA containing four W1W2 repeats as bait and an EBV-transformed human peripheral blood lymphocyte cDNA library as the source of cellular genes. Our results were as follows. (i) All three cDNAs in positive yeast colonies were found to encode the same cellular protein, HS1-associated protein X-1 (HAX-1), which is localized mainly in the cytoplasm and has been suggested to be involved in the regulation of B-cell signal transduction and apoptosis. (ii) Mutational analysis of EBNA-LP revealed that the association with HAX-1 is mediated by the W1W2 repeat domain. (iii) A purified chimeric protein consisting of glutathione S-transferase fused to EBNA-LP specifically formed complexes with HAX-1 transiently expressed in COS-7 cells. (iv) When EBNA-LP and HAX-1 were coexpressed in COS-7 cells, EBNA-LP was specifically coimmunoprecipitated with HAX-1. (v) Careful cell fractionation experiments of an EBV-infected lymphoblastoid cell line revealed that EBNA-LP is localized in the cytoplasm as well as in the nucleus. (vi) When EBNA-LP containing four W1W2 repeats was expressed in COS-7 cells, EBNA-LP was detected mainly in the nucleus by immunofluorescence assay. Interestingly, when EBNA-LP containing a single W1W2 repeat was expressed in COS-7 cells, EBNA-LP was localized predominantly in the cytoplasm and was colocalized with HAX-1. These results indicate that EBNA-LP is in fact present and may have a significant function in the cytoplasm, possibly by interacting with and affecting the function of HAX-1.

Significance of K-ras mutation and CEA level in pancreatic juice in the diagnosis of pancreatic cancer

The early diagnosis of pancreatic carcinoma is essential for increasing patient survival rates. In this study, 52 patients with suspected pancreatic diseases were examined to investigate the value of K-ras codon 12 point mutation, levels of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA19-9), and cytology of pancreatic juice in the diagnosis of pancreatic carcinoma. Pancreatic juice was taken without secretin stimulation. K-ras mutation was detected by enriched polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). K-ras mutation in pancreatic juice was more frequent in carcinoma than in benign diseases (P = 0.0448). The positive predictive value of K-ras mutation for the diagnosis of neoplastic disease was 83%. The CEA level in pancreatic juice in carcinoma was significantly greater than that in benign disease (P< 0.0001). When the cutoff level of CEA was set at 50 ng/ml, its accuracy for the diagnosis of carcinoma was 85%. A multivariate analysis showed that K-ras mutation and CEA level in pancreatic juice, as well as serum CA19-9 level and age of the patient were independent variables for the diagnosis of carcinoma, and the accuracy of diagnosis by this analysis was increased to 90%. In conclusion, both K-ras mutation and CEA level in pancreatic juice may be valuable for the diagnosis of carcinoma. Better discrimination was possible with a multivariate analysis.

Successful treatment of tumoral calcinosis using CAPD combined with hemodialysis with low-calcium dialysate

Successful treatment of tumoral calcinosis using continuous ambulatory peritoneal dialysis (CAPD) combined with hemodialysis is described. A 32-year-old male patient with a 2-year history of CAPD rapidly developed multiple metastatic calcification (tumoral calcinosis) adjacent to his fingers, elbows, and knee joints. Tests showed severe hyperphosphatemia, moderate hypercalcemia, and increased Ca-P product without elevation of intact parathyroid hormone. An enlarged parathyroid gland was not found by echography. In order to rapidly lower the excessive Ca and P levels, a combined therapy with CAPD and vigorous transient hemodialysis using a low-Ca dialysate was performed. In parallel, the patient was given calcitonin, bisphosphonate, and short-term Al to ameliorate the metastatic calcifications more effectively. The result was dramatic with disappearance of the tumoral calcinosis as well as improvement in subjective symptoms within a few months. The present case suggests that combined therapy with hemodialysis and CAPD using a low-Ca dialysate, together with Ca-modulating agents, can be effective in ameliorating tumoral calcinosis in patients on CAPD.

Tissue distribution and biotransformation of potassium oxonate after oral administration of a novel antitumor agent (drug combination of tegafur, 5-chloro-2,4-dihydroxypyridine, and potassium oxonate) to rats

S-1, a new oral 5-fluorouracil (5-FU)-derivative antitumor agent, is composed of tegafur, 5-chloro-2,4-dihydropyridine, and potassium oxonate (Oxo). Oxo, which inhibits the phosphorylation of 5-FU, is added to reduce the gastrointestinal (GI) toxicity of the agent. In this study, we investigated the tissue distribution and the metabolic fate of Oxo in rats after oral administration of S-1. Oxo was mainly distributed to the intracellular sites of the small intestines in a much higher concentration than 5-FU, but little distributed to other tissues, including tumorous ones in which 5-FU was observed after oral administration of S-1. Plasma concentration-time profiles of Oxo and its metabolites after i.v. and oral administration of S-1 revealed that Oxo was mainly converted to cyanuric acid in the GI tract. Furthermore, the analysis of drug-related radioactivity in GI contents and in vitro studies suggested that Oxo was converted to cyanuric acid by two routes, the first being direct conversion by the gut flora in the cecum, and the second, conversion by xanthine oxidase or perhaps by aldehyde oxidase after degradation to 5-azauracil (5-AZU) by the gastric acid. These results indicate that, although a part of the administered Oxo was degraded in the GI tract, Oxo was mainly distributed to the intracellular sites of the small intestines in a much higher concentration than 5-FU and that little was distributed to other tissues, including tumors. We conclude that this is the reason why Oxo suppresses the GI toxicity of 5-FU without affecting its antitumor activity.

Pharmacokinetic interactions between HIV-1 protease inhibitors in rats: study on combinations of two kinds of HIV-1 protease inhibitors

The drug interactions between four human immune deficiency virus (HIV-1) protease inhibitors have been characterized by in-vitro metabolic studies using rat liver microsomal fractions and in-vivo oral administration. In this study, a new HPLC analytical method developed by us was used for the simultaneous determination of saquinavir and nelfinavir in rat plasma and microsomes. The metabolic clearance rates (Vmax/Km) of saquinavir, nelfinavir, and indinavir were 170.9 +/- 10.9, 126.1 +/- 4-4, and 73.0 +/- 2.0 microL min(-1) (mg protein)(-1), respectively. Ritonavir was the strongest inhibitor with inhibition constants (Ki) of 1.64 microM for saquinavir, 0.95 microM for indinavir, and 1.01 microM for nelfinavir. Nelfinavir was the second strongest inhibitor with Ki's of 2.35 microM for saquinavir and 2.14 microM for indinavir. Indinavir was the third strongest inhibitor with Ki's of 2.76 microM for nelfinavir and 3.55 microM for saquinavir. Saquinavir was the weakest inhibitor for the other three HIV- 1 protease inhibitors. After oral co-administration in combination with another HIV-1 protease inhibitor, the AUCs of saquinavir, indinavir, and nelfinavir were significantly increased compared with mono-treatment. The AUCs of saquinavir were increased about 10.1-, 3.1- and 45.9-fold in the presence of indinavir, nelfinavir and ritonavir, respectively. The AUCs of indinavir were increased about 6.8-, 5.9- and 9.4-fold in the presence of nelfinavir, saquinavir and ritonavir, respectively. The AUCs of nelfinavir were increased about 2.2-, 6.6- and 8.5-fold in the presence of indinavir, saquinavir and ritonavir, respectively. The in-vivo effects observed after co-administration of two kinds of HIV-1 protease inhibitor were not always expected from in-vitro data, suggesting the presence of other interaction processes besides metabolism in the liver. These results provide useful information for the treatment of AIDS patients receiving combination therapy with two HIV-1 protease inhibitors.

Intraarticular osteoid osteoma associated with synovitis: a possible role of cyclooxygenase-2 expression by osteoblasts in the nidus

To clarify the condition of development of synovitis associated with intraarticular osteoid osteoma (OO), expressions of cyclooxygenase-2 (COX-2) protein and its messenger ribonucleic acid were investigated both in the nidus and the synovial tissue using immunohistochemical and reverse transcription-polymerase chain reaction analyses. Diffuse and strong COX-2 immunoreactivity was found in osteoblast-like tumor cells in the nidus of all six cases of OO (three of six cases were intraarticular OO associated with synovitis) and one case of osteoblastoma associated with synovitis. Expression of COX-2 messenger ribonucleic acid was demonstrated in one case of OO associated with synovitis, and was higher in the nidus than that in the inflamed synovial tissue. However, there were no significant difference between the nidus and synovium in the expression of cytosolic phospholipase A2, one of the enzymes involved in arachidonic acid metabolism, and inflammatory cytokines such as interleukin-1beta and tumor necrosis factor alpha. Finally, as there was only one case in which the examinations of gene expression were performed, no definitive overall conclusions could be reached; rather it is suggested that COX-2 expressed primarily by osteoblasts in the nidus of intraarticular OO may play a role in activating the pathway of arachidonic acid metabolism, resulting in synovitis of the involved joint.

Histochemistry and morphology of the multifidus muscle in lumbar disc herniation: comparative study between diseased and normal sides

STUDY DESIGN

This comparative study was conducted on 19 patients (13 men and 6 women) with lumbar disc herniation (LDH). The histologic and histochemical differences and changes in the back muscles of the diseased and normal sides were evaluated.

OBJECTIVES

To determine the histologic differences in the back muscles between the diseased and normal sides in lumbar disc herniation.

SUMMARY OF BACKGROUND DATA

The morphologic changes of back muscles between the diseased and normal sides in lumbar disc herniation were examined using histologic and histochemical methods. Few studies have reported the difference in these changes based on quantitative analyses.

METHODS

All samples were harvested bilaterally from the multifidus muscle at the level of L4-L5 or L5-S1 in patients with lumbar disc herniation and then were examined by histologic and histochemical methods (hematoxylin-eosin, Gomori trichrome, NADH-TR, and ATPase stains). The percentage, cross-sectional area (CSA), and lesser diameter (LD) of muscle fibers were measured using computerized image analysis. The Wilcoxon, paired t, Kruskal Wallis, and Fisher tests were used for statistical analysis.

RESULTS

Both Type I and II fibers in the diseased side were significantly smaller than those from the normal side. In the diseased side, the potential strength of Type II fibers was weakened. Some pathologic changes (fiber type grouping, small angulated fibers, group atrophy, moth-eaten appearance, and internal nuclei, etc.) in the diseased side were more obvious than those in the normal side. When the straight leg raising test results were abnormal, both Type I and II fibers in the diseased side were smaller than those in the normal side. The Type I fibers of the diseased side were significantly smaller when the patients had symptoms of central low back pain. The size of the Type I fibers as well as of the Type II fibers did not differ between the diseased and normal sides in patients with unilateral and bilateral low back pain.

CONCLUSIONS

The present study indicated that there were differences in the characteristics of the multifidus muscle between the diseased and normal sides in patients with lumbar disc herniation. The changes in muscle characteristics primarily were related to the disc protrusion. In addition, different locations of the low back pain seemed to cause different secondary effects on the muscle characteristics.