Bicipital radial bursitis: CT and MR appearance

The authors present two cases of bicipital radial bursitis in the elbow. In these two cases, different CT and MR imaging patterns were observed. In the first case, postcontrast CT inhomogeneously enhanced the entire lesion. T1-weighted MR images showed the lesion with iso-signal intensity with muscle. T2-weighted images demonstrated the lesion with inhomogeneous high signal intensity, with internal, linear hypointensity. Histologically, the lesion consisted of hypertrophic synovia. In the second case, postcontrast CT failed to enhance the lesion. T2-weighted MR images showed the lesion with homogeneous, marked high signal intensity. Histologically, the lesion consisted of a monocystic bursa lined by thin synovial lining layers.

Involvement of nitric oxide in the ocular hypotensive action of nipradilol

PURPOSE

To evaluate the role of nitric oxide (NO) in the mechanism of the ocular hypotensive action of nipradilol, a beta-blocker with alpha( 1)-blocking activity.

METHODS

Change in intraocular pressure (IOP) of albino rabbits was measured after a single application of carboxy-PTIO (c-PTIO), an NO trapping agent. Next, IOP change was measured every hour for 5 hours after the instillation of 0.25% nipradilol into one of the eyes with and without c-PTIO pretreatment of both eyes. IOP change induced by desnitro-nipradilol was also examined. The outflow facility and uveoscleral outflow were determined by two-level constant pressure and anterior chamber perfusion methods before and at 3 hours after the application of nipradilol with and without c-PTIO pretreatment.

RESULTS

Topical administration of c-PTIO showed no significant effect on IOP. Unilateral instillation of nipradilol reduced IOP significantly compared with control eyes with a maximum reduction of 3.6 mmHg and effect duration of 3 hours. Pretreatment with c-PTIO partially inhibited the reduction during an earlier period (1 approximately 2 hours) and completely at 3 hours. IOP change by desnitro-nipradilol was similar to that by nipradilol with c-PTIO pretreatment. Nipradilol increased both outflow facility and uveoscleral outflow at 3 hours, whereas pretreatment with c-PTIO inhibited both of these outflows.

CONCLUSIONS

Results indicate that ocular hypotensive action by nipradilol during the relatively late period may be mainly due to enhancement of aqueous humor outflow by NO at least in the rabbits.

[Narcolepsy in a prepubertal boy]

We reported a 10-year-old boy with narcolepsy, the onset of which was at the age of 8 years and 6 months. The initial symptom was excessive daytime sleepiness, followed by cataplexy and disrupted nocturnal sleep. There was neither hallucination nor sleep paralysis. A daytime polysomnogram showed a sleep-onset rapid eye movement period (SOREMP), and human leukocyte antigen (HLA) analysis revealed HLA-DR2/DQB1 * 0602. Treatment with methylphenidate and clomipramine was effective; methylphenidate (30 mg/day) improved his wakefulness and alertness throughout the day, and clomipramine (20 mg/day) reduced the number of cataplexic episodes. Because of their abnormal behavior, prepubertal narcoleptic children may often be misdiagnosed as having epilepsy or an attention deficit hyperactivity disorder. Therefore, they need early diagnosis and treatment. Assistance should be provided to protect them from being labeled as lazy by their parents and school teachers.

Heightened ability of monocytes from sarcoidosis patients to form multi-nucleated giant cells in vitro by supernatants of concanavalin A-stimulated mononuclear cells

The main immunocompetent cells in sarcoidal lesions are epithelioid cells and multi-nucleated giant cells (MGC), both of which are derived from monocyte-macrophage lineage cells. To understand further the relevance of monocytes in sarcoidosis, we examined in vitro MGC formation using monocytes from sarcoidosis patients, patients with other granulomatous diseases (OGD) and healthy control subjects. The supernatant of concanavalin A-stimulated peripheral blood mononuclear cells (conditioned medium) generated Langhans type-MGC and foreign body type-MGC from monocytes. Conditioned medium from any three groups had the same ability to form MGC from normal monocytes. On the other hand, MGC were more highly formed using monocytes from sarcoidosis patients than from other groups. When macrophages induced by treatment of monocytes with macrophage colony-stimulating factor (M-CSF) were used, the rate of MGC formation in sarcoidosis patients was about threefold or fourfold as much as that in OGD patients or healthy controls, respectively. Oxidized ATP inhibited MGC formation in all groups. The susceptibility of monocytes cultured in conditioned medium for 24 h to 2'- and 3'-o-(4-benzoyl-benzoyl)ATP-mediated cytolysis was significantly higher in sarcoidosis patients than other groups. These findings suggest that the ability of monocytes to form MGC through P2x7 receptors is enhanced in sarcoidosis patients.

Pronociceptive effects of nociceptin/orphanin FQ (13-17) at peripheral and spinal level in mice

The heptadecapeptide nociceptin/orphanin FQ (N/OFQ) is reported to be metabolized by aminopeptidase N and endopeptidase 24.15. In the present study, N/OFQ C-terminal fragments elicited nociceptive responses in the peripheral nociceptors and in the spinal cord, whereas N-terminal fragments had no significant nociception. The nociceptive effect of N/OFQ (13-17) was most potent and remained unchanged in N/OFQ peptide receptor (NOPR) gene knockout mice, indicating that N/OFQ (13-17)-induced nociception is mediated through a novel mechanism independent of the activation of NOPR. This finding was further confirmed by in vitro guanosine 5'-O-(3-[35S]thio)triphosphate binding experiments, in which N/OFQ (13-17) showed no significant binding activity in baculovirus/sf21 cells expressing NOPR together with G protein alpha(i)1-, beta1-, and gamma2-subunits, whereas N/OFQ showed stimulation in a concentration-dependent manner. On the other hand, although a typical bell-shaped dose-response relationship was observed with a wide range of N/OFQ doses in both peripheral and central nociception tests, N/OFQ (13-17) did not show bell-shaped dose-response relationship in the central nociception test. This finding indicates that N/OFQ (13-17), in contrast to N/OFQ, lacks the postsynaptic antinociceptive actions modulating substance P signaling in the spinal cord. Together, our results suggest that C-terminal fragments of N/OFQ have potent nociceptive actions, and N/OFQ (13-17) could have the potential to mediate its actions through a novel mechanism independent of the activation of NOPR in the nociceptors and in spinal synapses.

Tissue-specific autoregulation of the stat3 gene and its role in interleukin-6-induced survival signals in T cells

Signal transducer and activator of transcription 3 (STAT3) mediates signals of various growth factors and cytokines, including interleukin-6 (IL-6). In certain IL-6-responsive cell lines, the stat3 gene is autoregulated by STAT3 through a composite IL-6 response element in its promoter that contains a STAT3-binding element (SBE) and a cyclic AMP-responsive element. To reveal the nature and roles of the stat3 autoregulation in vivo, we generated mice that harbor a mutation in the SBE (stat3(mSBE)). The intact SBE was crucial for IL-6-induced stat3 gene activation in the spleen, especially in the red pulp region, the kidney, and both mature and immature T lymphocytes. The SBE was not required, however, for IL-6-induced stat3 gene activation in hepatocytes. T lymphocytes from the stat3(mSBE/mSBE) mice were more susceptible to apoptosis despite the presence of IL-6 than those from wild-type mice. Consistent with this, IL-6-dependent activation of the Pim-1 and junB genes, direct target genes for STAT3, was attenuated in T lymphocytes of the stat3(mSBE/mSBE) mice. Thus, the tissue-specific autoregulation of the stat3 gene operates in vivo and plays a role in IL-6-induced antiapoptotic signaling in T cells.

Cloning and characterization of a novel mouse immunoglobulin superfamily gene expressed in early spermatogenic cells

We cloned and characterized a novel immunoglobulin superfamily gene from the cDNA library of adult mouse testis. This gene was expressed in the spermatogenic cells and hence termed SgIGSF. The predicted SgIGSF protein was composed of 445 amino-acid residues and contained a signal peptide, three extracellular immunoglobulin (Ig)-like domains, a transmembranous domain, and a cytoplasmic domain. SgIGSF mRNA consisted of two size species, 2.1- and 4.5-kb in length. Besides testis, SgIGSF mRNA was also expressed in a variety of organs, including the cerebrum, liver, kidney, and epididymis. The testis and liver expressed both the 2.1- and 4.5-kb transcripts, whereas the cerebrum and epididymis predominantly expressed the 4.5-kb one. In situ hybridization analysis in testis revealed that SgIGSF mRNA signal was localized to the spermatogenic cells from spermatogonia to zygotene spermatocytes. These results suggested that SgIGSF occurs in the plasma membrane of spermatogenic cells during the earlier stages of spermatogenesis.

Serum platelet-activating factor acetylhydrolase (PAF-AH) activity in more than 3000 healthy Japanese

BACKGROUND

A spectrophotometric assay for platelet-activating factor acetylhydrolase (PAF-AH) activity differs from the radioisotopic assay in its value because of a difference in substrate specificity. The spectrophotometric assay is more precise than the radioisotopic assay, providing information that is not clear with the radioisotopic assay.

METHODS

We measured the serum PAF-AH activity in 3106 healthy Japanese, utilizing the spectrophotometric assay with an Hitachi 7170 automatic analyzer. We also measured the serum PAF-AH activity in 18 healthy volunteers to investigate the effect of diet and the change in activity in a day and over 6 weeks. Changes were examined at 0 (day 1), 1, 2, 4 and 6 weeks.

RESULTS

The mean value for females was significantly lower than that of males at the 5% level and both male and female activity had a tendency to increase with advancing age. It is known that the PAF-AH is primarily associated with LDL in blood and the PAF-AH activity correlated with the total cholesterol (r=0.52, n=126) and the LDL cholesterol (r=0.60, n=126) concentrations. In the diet study, there was no observable effect on activity. No difference in PAF-AH activity was observed between serum and plasma sample types. The serum PAF-AH activity was stable at 7 degrees C for at least 7 days and at -20 degrees C for at least 2 months.

CONCLUSIONS

The serum PAF-AH activity in women was lower than in men until the menopausal age was reached. We could use not only fresh fasting serum, but also plasma sample, non-fasting sample and stored sample to estimate the PAF-AH activity.

Histologic analysis of the implanted cartilage in an exact-fit osteochondral transplantation model

PURPOSE

Osteochondral transplantation is one of the useful treatments for articular cartilage defect. However, the histologic change of the implanted cartilage has not been reported in detail. We investigated the histology of exact-fit osteochondral transplants used to repair articular cartilage defects in an animal model.

TYPE OF STUDY

This was a nonrandomized control study using an animal model.

METHODS

Sixteen skeletally mature female Japanese white rabbits were used in the study. The region of the femoral groove was selected as the site for the osteochondral defect. A full-thickness cylindrical defect (7 mm in diameter and 7 mm in depth) through the articular cartilage and into the subchondral bone was made using the Osteochondral Autograft Transfer System (Arthrex, Naples, FL). The entire osteochondral fragment was removed and then returned to its original site in the femoral condyle precisely. Thus, the defect was repaired with an autogenous osteochondral transplantation of exactly the same size and configuration as the defect. Specimens were obtained 2, 4, 12, and 24 weeks postoperatively and were analyzed both macroscopically and histologically.

RESULTS

Macroscopically, there was smooth continuity of the articular surface and the integration of the graft to the normal host cartilage. However, histologic examination showed that the layer of the grafted cartilage was thicker than that of the normal host cartilage and the extracellular matrix of the implanted cartilage exhibited a stronger staining pattern with safranin-O fast green than the normal cartilage. Cell density was higher in the grafted cartilage, particularly in the middle and the deep zones. Round and polygonal hypertrophic clusters of chondrocytes were observed in the middle and deep zones of the grafted cartilage.

CONCLUSIONS

The histologic properties of the exact-fit implanted cartilage were different from that of normal articular cartilage. Further investigation of mechanical and structural properties of grafted cartilage is necessary to verify the long-term effects of osteochondral transplantation.

Muramyl dipeptide and mononuclear cell supernatant induce Langhans-type cells from human monocytes

Muramyl dipeptide (MDP) in bacterial cell walls reportedly evokes epithelioid cell granulomas. We examined its effects on multinucleated-giant-cell (MGC) formation from monocytes. Supernatant of concanavalin A-stimulated peripheral blood mononuclear cells (conditioned medium) generated MGCs from monocytes. MDP significantly increased the fusion index of Langhans-type MGCs (LGCs) but did not affect total MGCs. N-Acetylmuramyl-L-alanyl-L-isoglutamine, an MDP analogue, had no effect on MGC formation. MGCs were produced by conditioned medium from CD14(++)/CD16(-) monocytes. MDP enhanced the LGC fusion index from CD14(++)/CD16(-) monocytes. MGCs were not produced from CD14(+)/CD16(+) monocytes or immature dendritic cells induced by granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL) 4 and only weakly produced from macrophage (M)-CSF- or GM-CSF-induced macrophages. Added MDP did not generate MGCs from CD14(+)/CD16(+) monocytes or dendritic cells but enhanced LGC formation from macrophages. Because IFN-gamma, IL-3, and GM-CSF reportedly are important in LGC induction, we added anti-IFN-gamma, anti-IL-3, or anti-GM-CSF monoclonal antibody (mAb) concomitantly to the monocyte culture treated with conditioned medium alone or plus MDP. Anti-IFN-gamma mAb completely abrogated MGC generation, whereas anti-GM-CSF and anti-IL-3 mAbs significantly inhibited LGCs. These findings suggest that CD14(++)/CD16(-) monocytes are fused to form LGCs by MDP derived from granulomatous-disease-causing pathogens with inflammatory mediators such as IFN-gamma, IL-3, and GM-CSF.

Neurosteroids stimulate G protein-coupled sigma receptors in mouse brain synaptic membrane

Dehydroepiandrosterone, its sulfate (DHEAS) and pregnenolone sulfate, representative neurosteroids as well as (+)-pentazocine concentration-dependently stimulated the [35S]GTPgammaS binding in synaptic membranes of mouse prefrontal cortex. These stimulations were blocked by NE-100, a sigma-receptor antagonist, and by progesterone, another type of neurosteroid. The DHEAS-induced stimulation was blocked by the pertussis toxin (PTX)-treatment, and completely recovered by reconstitution of PTX-treated membranes with recombinant G(i1), but not with G(oA). DHEAS also stimulated the [35S]GTPgammaS binding in the coronal sections of mouse brain in NE-100- or progesterone-reversible manner. These findings suggest that some neurosteroids may act on metabotropic sigma receptors, and this study may be the first to show the coupling of neurosteroid binding site and G(i).

Dynamic changes in protein components of the tight junction during liver regeneration

The construction of the hepatocyte tight junction is one of the most important events during liver regeneration leading to the reorganization of the bile canaliculi and the repolarization of hepatocytes after cell division. To understand this event at the molecular level, we examined the expression of tight junction proteins by Western blot analysis and their cellular localization by immunofluorescence microscopy in regenerating rat liver after two-thirds hepatectomy. The levels of tight junction components such as claudin-3, ZO-1 and atypical protein kinase C (PKC)-specific interacting protein (ASIP) increased two- to three-fold over control levels in coordination with a peak 2-3 days after partial hepatectomy, whereas occludin levels remained unchanged. The bile canaliculi outlined by tight junction components and actin filaments reveal significant morphological changes from 2-3 days after partial hepatectomy. During this period, claudin-3/ZO-1 and ASIP/ZO-1 were nearly co-localized, whereas occludin was locally reduced or almost absent on the bile canaliculi outlined by ZO-1 staining. The uncoupled localization of F-actin and tight junction components was often observed. The function of hepatocytes, as revealed by the serum bile acids level, was distorted temporally at an early stage of regeneration but mostly restored 3 days after partial hepatectomy. These observations suggest that the de novo construction of tight junctions proceeds mainly 2-3 days after partial hepatectomy in parallel with the cell polarization required for hepatocyte function. However, the complete normalization of the composition of the tight junction components, such as occludin and the association with F-actin, requires additional time, which may support the regeneration of fully polarized normal hepatocytes.

Cell-type-specific expression of a TESK1 promoter-linked lacZ gene in transgenic mice

Testicular protein kinase 1 (TESK1) is a serine/threonine kinase highly expressed in testicular germ cells and has the potential to phosphorylate cofilin and induce actin cytoskeletal reorganization. We examined the expression of a lacZ reporter gene linked to a 9.0-kb 5'-flanking region of TESK1 gene in transgenic mice. A high level of lacZ expression was observed in testicular germ cells only at stages after pachytene spermatocytes, the expression patterns being similar to those of TESK1 mRNA in rat testis, determined by in situ hybridization. Expression of lacZ was also detected in renal proximal tubules, cardiac myocytes, and specific neurons in the central nervous system in adult transgenic mice. Whole-mount staining revealed the expression of lacZ in neural tissues in embryonic mice. These results suggest the cell-type- and stage-specific expression of TESK1 gene and the diverse and specific physiological functions of TESK1, including those in spermatogenesis and neural development.

Cofilin phosphorylation and actin reorganization activities of testicular protein kinase 2 and its predominant expression in testicular Sertoli cells

We previously identified testicular protein kinase 1 (TESK1), which phosphorylates cofilin and induces actin cytoskeletal reorganization. We now report identification and characterization of another member of a TESK family, testicular protein kinase 2 (TESK2), with 48% amino acid identity with TESK1. Like TESK1, TESK2 phosphorylated cofilin specifically at Ser-3 and induced formation of actin stress fibers and focal adhesions. Both TESK1 and TESK2 are highly expressed in the testis, but in contrast to TESK1, which is predominantly expressed in testicular germ cells, TESK2 is expressed predominantly in nongerminal Sertoli cells. Thus, TESK1 and TESK2 seem to play distinct roles in spermatogenesis. In HeLa cells, TESK1 was localized mainly in the cytoplasm, whereas TESK2 was localized mainly in the nucleus, which means that TESK1 and TESK2 likely have distinct cellular functions. Because the kinase-inactive mutant of TESK2 was localized in the cytoplasm, nuclear/cytoplasmic localization of TESK2 depends on its kinase activity. A TESK2 mutant lacking the C-terminal noncatalytic region had about a 10-fold higher kinase activity in vitro and, when expressed in HeLa cells, induced punctate actin aggregates in the cytoplasm and unusual condensation and fragmentation of nuclei, followed by apoptosis. Thus, we propose that the C-terminal region plays important roles in regulating the kinase activity and cellular functions of TESK2.

Human endometrial stromal interleukin-1 beta: autocrine secretion and inhibition by interleukin-1 receptor antagonist

Decidualization of human endometrial stromal cells is suppressed by endometrial IL-1 in an autocrine or paracrine manner, indicating that constant suppression of stromal decidualization by IL-1 requires a neutralizing mechanism for IL-1 action to accept embryo implantation. Since production of IL-1ra in human endometrium is reported to be 10- to 30-fold higher than that of IL-1 alpha/beta, we investigated whether endogenous IL-1 beta secreted from human endometrial stromal cells can be inhibited by IL-1ra by using an in vitro decidualization culture. Human stromal cells were cultured with 8-Br-cAMP to induce decidualization, and concentrations of IL-1 beta, IL-8, and prolactin in the culture supernatants were assayed before and after decidualization. There was no significant difference in mean IL-1 beta concentrations measured before and after decidualization. Addition of IL-1ra to endometrial stromal cell cultures strongly inhibited endogenous IL-8 secretion from the cells. Although IL-1 beta showed a biphasic effect on cell proliferation and a suppressive effect on decidualization of stromal cells, these effects were completely inhibited by IL-1ra. The results imply that a high in vivo concentration of IL-1ra in human endometrial tissues may regulate IL-1 effects on decidualization and cell proliferation of human endometrial stromal cells.

Water-soluble and water-insoluble glucans produced by Escherichia coli recombinant dextransucrases from Leuconostoc mesenteroides NRRL B-512F

Two dextransucrase genes, dsrS and dsrT5, from Leuconostoc mesenteroides NRRL B-512F were expressed in Escherichia coli, and recombinant dsrT5 dextransucrase was shown to produce a water-insoluble glucan. In contrast, native dextran from L. mesenteroides B-512F is water-soluble. The water-insoluble glucan was shown by 13C NMR and glycosyl-linkage composition analysis to contain about 50% 6-linked Glcp and 40% 3-linked Glcp. The 'primitive' B-512F strain is suggested to have produced water-insoluble glucan containing 3-linked Glcp. The glucans produced by dextransucrases expressed in E. coli contained 4-linked Glcp, as shown by glycosyl-linkage composition analysis. The amount of 4-linked Glcp was increased when the truncated, water-insoluble, glucan-producing dextransucrase, which does not have C-terminal repeating units, was added to the water-soluble, glucan-producing dextransucrase. Trace amounts of 4-linked Glcp were also detected in the dextran obtained from the B-512F culture supernatant, in dextran produced by dextransucrase purified from the B-512F strain culture supernatant, and in clinical dextran. The results of glycosyl-linkage composition analysis suggest that dextransucrases produce 4-linked Glcp as well as 6- and 3-linked Glcp.

Parosteal lipoma of the distal phalanx: a case report and review of the literature

A rare case of parosteal lipoma of the distal phalanx in a small finger of a 68-year-old woman is reported. Radiographs revealed an osseous projection and cortical irregularity in the distal phalanx of the right small finger. Magnetic resonance imaging showed a hyperintense soft tissue mass adjacent to the phalanx on T1-weighted and T2-weighted images. Histologically, the lesion consisted of mature fat cells. Marginal excision of the lesion was curative.

Cell density-dependent death mode switch of cultured cortical neurons under serum-free starvation stress

1. Cell death mode switch of cortical neurons from E17 rats was studied. Cells rapidly died under the serum-free condition. The time-course of cell death was markedly delayed by increasing cell density for primary culture in the trypan blue exclusion, LDH release, and MTT assays. 2. By analyzing cell death by the use of double staining using PI/TUNEL and PI/Annexin V combinations, the mode in the low density culture was found to be necrosis, while that in the high density culture was apoptosis. 3. The intracellular ATP level after the start of serum-free culture rapidly decline to 25% of 0-time level in the low density culture, but it was 60% in the high density culture. Both oligomycin and zVAD-fmk markedly decreased ATP levels and the population of TUNEL-positive neurons, while 3-aminobenzamide slightly increased these indices. 4. Thus. it is strongly suggested that the cell death mode switch from necrosis to apoptosis is closely related to intracellular ATP levels, and some conditioned medium factors observed in the high density culture may affect both ATP level and cell death mode switch.

Sacral radiculopathy secondary to multicentric osteosarcoma

STUDY DESIGN

A case of multicentric osteosarcoma presenting with sacral radiculopathy is reported.

OBJECTIVE

To present unusual clinical and radiologic findings of multicentric osteosarcoma.

SUMMARY OF BACKGROUND DATA

Multicentric osteosarcoma is a rare variant of osteosarcoma. To the authors' knowledge, no cases of multicentric osteosarcoma presenting as sacral radiculopathy have been reported previously.

METHODS

A 14-year-old boy had a large sacral tumor extending into the spinal canal, which was found to account for the initial symptoms, which mimicked those of herniated nucleus pulposus. At diagnosis, a bone survey showed multiple foci of osteosarcoma in the long bones.

RESULTS

The patient was treated with chemotherapy, but died of the disease 8 months after the initial presentation.

CONCLUSION

Multicentric osteosarcoma should be considered in the differential diagnosis for a pediatric patient with low back pain and sciatica.

Ulnar bursa distention following volar subluxation of the distal radioulnar joint after distal radial fracture: a rare cause of carpal tunnel syndrome

This report describes an eighty-four-year-old woman with persistent carpal tunnel syndrome attributable to an ulnar bursa distention associated with the subluxation of the distal radioulnar joint after distal radial fracture. During surgery, when the forearm was placed in supination, the ulna head with a sharp osteophyte was found to be displaced into the carpal tunnel through a defect of the ruptured capsule of the wrist joint. This volar subluxation of the ulnar head had caused distention of the ulnar bursa, causing compression of the median nerve, which resulted in carpal tunnel syndrome. In addition to reduce displaced fractured segment to obtain anatomic articular surface, original radial length and tilt, the anatomic restoration of the distal radioulnar joint is essential to maintain better long-term function after fracture of the distal radius.

[Gadolinium-enhanced MR imaging, T2-weighted MR imaging, and transurethral ultrasonography]

PURPOSE

To assess the value and problems of dynamic gadolinium-enhanced MR imaging, T2-weighted MR imaging, and transurethral ultrasonography(TUUS) in staging of urinary bladder cancer.

MATERIALS AND METHODS

Dynamic gadolinium-enhanced MR imaging and FSE T2-weighted MR imaging of 64 patients with urinary bladder cancer who subsequently had surgery were retrospectively reviewed and compared with TUUS findings.

RESULTS

Specificity for muscular invasion was 90.5% with TUUS, significantly better than with dynamic MR imaging (64.9%) (p < 0.05). The rates of overestimation of superficial cancer(pT1) with dynamic MRI and T2-weighted MR imaging were 35.1%(13/37) and 24.3%(9/37), respectively. The staging accuracy of invasive cancer(pT2 or over) was 85.2% with dynamic MR imaging, which was better than the rate of 75.0% achieved with T2-weighted MR imaging.

CONCLUSION

Although TUUS was a better modality for diagnosing superficial cancer(pT1), dynamic MR imaging was found to be better for diagnosing invasive(pT2 or over) cancer.

Tubularized incised-plate urethroplasty for secondary hypospadias surgery

PURPOSE

Reoperation for failed hypospadias has been considered to be seriously bothersome because abundant penile skin does not tend to remain for urethroplasty or for penile shaft skin coverage. In this study, the tubularization of incised urethral plate was employed for those who had no excessive penile skin after failure of hypospadias repair.

METHODS

Five patients with hypospadias underwent tubularized incised-plate urethroplasty as salvage surgery. The surgical techniques necessary for the performance of the reoperation were not different from those for the primary repair. The urethral plate was incised sufficiently deeply in its midline from the tip of the glans to the regressed meatus. The incised urethral plate was tubularized without tension over a catheter of an appropriate size.

RESULTS

Four of those who underwent secondary tubularized incised-plate urethroplasty were successfully repaired without complications. A urethrocutaneous fistula occurred at the corona in the remaining patient.

CONCLUSIONS

The absence of preputial skin in reoperative cases makes tubularized incised-plate urethroplasty the ideal option, although the series was small and postoperative duration is still short. In addition, this procedure can give excellent functional and cosmetic results even in patients who require revisional hypospadias surgery.

Metabotropic neurosteroid/sigma-receptor involved in stimulation of nociceptor endings of mice

In peripheral nociceptive flexor test, SA4503, (+)-pentazocine, and (+)-3-(hydroxyphenyl)-N-(1-propyl)piperidine, representative sigma-receptor agonists, elicited dose-dependent flexor responses. These responses were blocked by sigma-receptor antagonists NE-100 or BD1063, but not by pretreatments with antisense oligodeoxynucleotide for sigma1 binding protein. The sigma-agonists' nociception is attributed to the substance P (SP) release from nociceptor endings through activations of Galpha(i1) and phospholipase C (PLC). On the other hand, attomolar doses of neurosteroids such as dehydroepiandrosterone sulfate (DHEAS) and pregnenolone sulfate caused similar nociception, and they were blocked by progesterone (PROG). However, DHEAS nociception was not affected by pertussis toxin, but was completely inhibited by a PLC inhibitor or thapsigargin. Although the nociception by lower doses of DHEAS was abolished by diphenhydramine (DPH), H1 antagonist, there were dose-dependent responses by high doses of DHEAS in the presence of DPH. The responses by DHEAS in the presence of DPH were blocked by NE-100, and those by (+)-pentazocine were blocked by PROG. All these findings suggest that two novel types of neurosteroid receptors exist, neuronal NS1/sigma-type, which mediates activation of Galpha(i1) by neurosteroids and sigma-agonists, followed by SP release from nociceptor endings; and NS2 type, which mediates histamine release from mast cells by very low doses of neurosteroids.

Photoallylation and photoreduction of cyclohexylidenepropanedinitrile by use of allyltrimethylsilane via photoinduced electron transfer: control of the product ratio depending on pK(a) values of additives

Irradiation of an acetonitrile solution containing cyclohexylidenepropanedinitrile (1) and allyltrimethylsilane (2) in the presence of phenanthrene afforded two kinds of allylated products (3, 4) and a reduction product (5). The product ratio of 3, 4, and 5 dramatically changed depending on the pK(a) values of additives.

Pancreaticobiliary arteriovenous malformation with common bile duct dilation in a patient with hemobilia

Arteriovenous malformation of the pancreas is a very rare entity. We describe a case involving the head of the pancreas associated with progressive hemobilia bleeding from the lower part of the common bile duct. The patient was a 50-year-old man with acute epigastralgia. Endoscopic retrograde cholangiopancreatography revealed hemobilia and cystic dilation of the common bile duct. Angiography demonstrated increased blood volume in the head of the pancreas and early filling of the superior mesenteric and portal veins. Abdominal pain and progressive anemia caused by hemobilia required surgical treatment. Histologic examination of the resected specimen revealed marked proliferation of the blood vessels in the pericholedochal area and the exact point of bleeding from the pancreaticobiliary arteriovenous malformation.

Mechanical and structural characteristics of vulnerable plaques: analysis by coronary angioscopy and intravascular ultrasound

OBJECTIVES

Mechanical and structural characteristics of vulnerable plaques were evaluated using coronary angioscopy and intravascular ultrasound.

BACKGROUND

Mechanical stress and composition of plaques play an important role in plaque disruption.

METHODS

Thirty-eight lesions in 38 patients were examined pre-interventionally. The plaques were classified as either yellow or white using coronary angioscopy. Intravascular ultrasound imaging was performed simultaneously with electrocardiographic and intracoronary pressure recordings to calculate distensibility index and stiffness beta. Moreover, the type of remodeling was classified.

RESULTS

We identified 27 patients with yellow plaques and 11 patients with white plaques. Patients with yellow plaques presented acute coronary syndromes more frequently than stable angina (85% vs. 36%, p < 0.01). The distensibility index in yellow plaques was significantly greater than it was in white plaques (2.7 +/- 0.8 mm Hg(-1) vs. 0.7 +/- 0.8 mm Hg(-1), p < 0.0001), while stiffness beta for white plaques was significantly greater than it was for yellow plaques (34.9 +/- 16.3 vs. 8.7 +/- 2.7, p < 0.0001). Compensatory enlargement occurred more frequently with yellow plaques than with white plaques (56% vs. 9%, p < 0.01), while paradoxical shrinkage occurred more frequently with white plaques than it did with yellow plaques (64% vs. 4%, p < 0.001).

CONCLUSIONS

Yellow plaques with an increased distensibility and a compensatory enlargement may be mechanically and structurally weak. As a result, mechanical "fatigue," caused by repetitive stretching, may lead to plaque disruption. Plaques with a high distensibility and a compensatory enlargement may be vulnerable.

The YXXQ motif in gp 130 is crucial for STAT3 phosphorylation at Ser727 through an H7-sensitive kinase pathway

The signal transducer and activator of transcription (STAT) 3 is essential for mediating signals from the receptors for a variety of cytokines and growth factors, including IL-6 and EGF, and from cytoplasmic tyrosine kinases. Upon stimulation, STAT3 is phosphorylated at Ser727 and Tyr705. However, the role of phosphorylation at Ser727, and the kinase pathways responsible for this phosphorylation in IL-6 signaling remain obscure. Here we show that IL-6 activates at least two distinct STAT3 serine kinase pathways and that an H7-sensitive pathway is dominant over a PD98059-sensitive one in HepG2 cells stimulated with a low concentration of IL-6. The analysis, using a series of chimeric receptors containing the extracellular domain of the G-CSF receptor, the truncated form of gp 130, and additional short peptides at the gp 130 carboxy-terminus, showed that the YXXQ motif of gp 130 was sufficient for the H7-sensitive STAT3 Ser727 phosphorylation. This YXXQ-mediated pathway does not involve Erk, p38, JNK, or PKCdelta, and requires a site in the region from 533 to 711 of STAT3 for phosphorylation in vivo. Moreover, we show that Ser727 is required for full transcriptional activity of STAT3 for two different response elements. Thus, the YXXQ motif regulates STAT3 activities in two ways in response to even a low concentration of IL-6: it recruits STAT3 to the receptor for tyrosine phosphorylation, and activates an unidentified H7-sensitive pathway leading to the serine phosphorylation of STAT3.

Radiographic and computed tomographic analysis of the position of the tibial tubercle in recurrent dislocation and subluxation of the patella

Among the factors that influence the patellofemoral alignment and stability, the position of the tibial tubercle was evaluated using plain radiographs and computed tomography (CT). Radiographs of the Q-angle with the knee in full extension and quadriceps muscle relaxed showed that mean Q-angles in the dislocation or subluxation group and control group were 13.8 degrees and 14.3 degrees, respectively. The major reason for this deceptive measurement was a patella positioned laterally in the dislocation or subluxation group. Better estimation was made with the modified Q-angle measurement by using the most concave point of the intercondylar notch as a reference point instead of the center of the patella. By overshadowing CT images of the levels of the patellofemoral joint and the tibial tubercle, it was possible to evaluate the location of the tibial tubercle in relation to the femoral trochlea. Both the angular measurement (lateral deviation angle [LDA]) and the distance measurement (lateral deviation index [LDI]) showed that the tibial tubercle in the dislocation or subluxation group was rotated externally and shifted laterally (LDA, 36.3+/-7.0 degrees and LDI, 30.1+/-5.6) compared with the control group (LDA, 20.2+/-7.1 degrees and LDI, 15.1+/-5.6). Further study is warranted to elucidate the exact mechanism of recurrent patellar dislocation and subluxation.

Development of sucking behavior in infants who have not been fed for 2 months after birth

BACKGROUND

Term infants are able to develop sucking behavior after birth. However, the requirements for this development have not yet been fully elucidated. In the present study, we investigated whether an oral-feed practice is necessary for the development of sucking behavior and whether non-nutritive sucking could support the development of this behavior while the infants cannot be fed.

METHODS

Subjects of the present study were four term or near-term infants who had never been fed orally for approximately 2 months after birth because of gastrointestinal problems. Sucking pressure was measured with a silicone tube inserted into an artificial nipple and sucking efficiency was calculated during an entire feeding.

RESULTS

Sucking pressure, frequency and duration at the first time oral feed corresponded to values obtained for normal-term infants at their first oral feed. Although infants who had not received oral feeding demonstrated poor sucking abilities initially, sucking performance improved with practice. Sucking parameters measured 1 month since oral feeding was initiated in these infants corresponded to values obtained for normal-term infants at 1 month of age. Although infants who had not received oral feeding had often sucked a pacifier for sedation, this non-nutritive sucking did not result in the development of sucking behavior.

CONCLUSIONS

These results demonstrate that an oral feeding practice is necessary for the development of sucking behavior and that non-nutritive sucking does not affect the development of sucking.

No involvement of Erk/MAP kinases in IL-6-induced proliferation of a B cell hybridoma cell line

Interleukin-6 (IL-6) is a pleiotropic cytokine and acts as a growth factor for murine plasmacytoma and human myeloma. IL-6 activates multiple signal transduction pathways. Among them, signal transducer and activator of transcription3 (STAT3), and the SHP-2-mediated Erk/MAP kinase pathway are important. The roles for the two major pathways in the IL-6-induced growth of B cell hybridoma cells were examined. A mutational analysis of the cytoplasmic domain of exogenously expressed gp130, a signal transducing beta chain of the IL-6 receptor complex, revealed that the proximal 133 amino acid (AA) region of gp130 with the intact Y767 but not Y759 is necessary and sufficient for gp130-signal-induced cell proliferation. Interestingly, no requirement of the Y759-mediated signals, including SHP-2-mediated Erk/MAP kinase pathway, coincided with the failure of SHP-2, Gab1/Gab2, and Erk/MAP kinase activation by IL-6 in MH60 cells. Moreover, we show that another serine/threonine kinase pathway leading to STAT3 Ser727 phosphorylation, which seemed to be derived from the Y767 in the proximal 133 AA residues, is intact in MH60 cells. Since Erk/MAP kinases are known to inhibit the subsequent IL-6-induced STAT3 activation, the impaired activation of Erk/MAP kinases by IL-6 may contribute to the development of B cell neoplasia.

Molecular properties and gene expression of albumin in the skeletal muscle following hindlimb immobilization in a shortened position

We investigated the effect of immobilization of hindlimb in a shortened position on proteins in the mouse soleus muscle and determined the molecular properties of a protein that had changed specifically in the atrophied muscle. A protein of 67.5 kDa was increased significantly (P<0.001) by 1.9-fold in the atrophied muscle compared to the control muscle as shown by sodium dodecyl sulfate-polyacrylamide (SDS-PAGE). The isoelectric point of the protein was pH 6.3 in two-dimensional PAGE. We carried out N-terminal and peptide mapping analyses to identify the primary structure of the protein. A 17-amino acid sequence showed 100% homology with the mouse serum albumin precursor. A peptide map of the 67.5-kDa protein was similar to that of mouse serum albumin. Mass spectrometry also showed the protein to be most similar to mouse serum albumin. Thus, based on these criteria, the 67.5-kDa protein was indistinguishable from mouse serum albumin. An immunohistochemical study showed that the 67.5-kDa protein was located mainly in the endomysium of the control muscle and had accumulated in the widened interstitial spaces of the atrophied muscle. A reverse transcription-PCR assay revealed that the albumin gene was expressed in skeletal muscle tissue, but that its expression was significantly lower in the atrophied muscle than in the control muscle (P<0.001). We conclude that albumin is increased in atrophied muscle and suggest that this may be of clinical importance for analyzing the process of muscular atrophy.

Elastofibroma in shoulder osteoarthritis: a theoretical concept of the etiology

A case of unilateral, subscapular elastofibroma dorsi secondary to degenerative osteoarthritis in the ipsilateral glenohumeral joint is presented. A 69-year-old woman had experienced symptoms of osteoarthritis in the right shoulder since contracting septic arthritis when she was 7 years old. The patient noticed a soft tissue mass in the right subscapular region when she was 65 years old. The range of motion of the glenohumeral joint was severely restricted. Histopathologic examination of the excised mass revealed elastofibroma. The authors think the excessive scapulothoracic motion was important in formation of the lesion. This case indicates that elastofibroma is not a true neoplasm but a reactive lesion formed by repetitive minor trauma.

Pharmacological Properties of Fidarestat, a Potent Aldose Reductase Inhibitor, Clarified by Using Sorbitol in Human and Rat Erythrocytes

We examined the effect of fidarestat on the increase in sorbitol content in erythrocytes from healthy volunteers in vitro. Fidarestat inhibited the increase with an IC50 value of 18 nmol/l. A subsequent experiment showed that fidarestat had a similar inhibitory effect on the increase in sorbitol content in erythrocytes from diabetic patients. On the other hand, epalrestat, the only aldose reductase inhibitor used clinically, inhibited increase in sorbitol content at a concentration over 500-fold higher than fidarestat. Although the IC50 value of fidarestat was not affected by fasting plasma glucose, HbA1C, age, aldose reductase content or gender, there was a significant positive relationship between the IC50 value of epalrestat and fasting plasma glucose. In addition, in fidarestat (0.25-2 mg/kg)-treated diabetic rats, the inhibitory rate for erythrocyte sorbitol accumulation was well correlated with that for nerve sorbitol accumulation, which indicates that erythrocyte sorbitol is available for assessing the state of sorbitol pathway flux in target tissue after fidarestat administration. These results suggest that fidarestat potently inhibits the increase in sorbitol pathway flux in diabetic patients independent of various factors and that erythrocyte sorbitol is useful for its estimation.

Spontaneous resolution of a phalangeal solitary osteochondroma

We report a solitary osteochondroma in the proximal phalanx of the ring finger in a 3-year-old boy that resolved spontaneously.

Characterization of an isoform of rice starch branching enzyme, RBE4, in developing seeds

cDNA clones encoding an isoform of starch branching enzyme, RBE4, have been identified from a developing rice seed cDNA library, using a synthetic oligonucleotide probe corresponding to the N-terminal amino acid sequence of RBE4. The cDNA-derived amino acid sequence indicated that RBE4 is initially produced as a precursor protein of 841 amino acids, including a 53-residue transit peptide at the N-terminus. The mature form of RBE4 shared a high degree of sequence identity (80%) with mature RBE3, and possessed an N-terminal extra sequence, as found in RBE3. Northern blot analysis demonstrated that the RBE4 gene is expressed in both leaves and developing seeds. The RBE4 gene was distinguished from the RBE1 and RBE3 genes by expression at the earlier stages of seed development. To examine enzymatic functions of RBE4, recombinant proteins were produced in Escherichia coli cells, and purified by two chromatographic separations. The branched alpha-glucans produced by the recombinant enzymes from potato amylose revealed the different patterns of oligosaccharide chain transfer. The peak of major branches of the products by RBE3 or RBE4 was 6 glucose units, whereas the peaks of major branches of the products by RBE1 were 6 and 11 glucose units. The similar property between RBE3 and RBE4 is supported by high similarity of the amino acid sequences between them.

Cofilin phosphorylation by protein kinase testicular protein kinase 1 and its role in integrin-mediated actin reorganization and focal adhesion formation

Testicular protein kinase 1 (TESK1) is a serine/threonine kinase with a structure composed of a kinase domain related to those of LIM-kinases and a unique C-terminal proline-rich domain. Like LIM-kinases, TESK1 phosphorylated cofilin specifically at Ser-3, both in vitro and in vivo. When expressed in HeLa cells, TESK1 stimulated the formation of actin stress fibers and focal adhesions. In contrast to LIM-kinases, the kinase activity of TESK1 was not enhanced by Rho-associated kinase (ROCK) or p21-activated kinase, indicating that TESK1 is not their downstream effector. Both the kinase activity of TESK1 and the level of cofilin phosphorylation increased by plating cells on fibronectin. Y-27632, a specific inhibitor of ROCK, inhibited LIM-kinase-induced cofilin phosphorylation but did not affect fibronectin-induced or TESK1-induced cofilin phosphorylation in HeLa cells. Expression of a kinase-negative TESK1 suppressed cofilin phosphorylation and formation of stress fibers and focal adhesions induced in cells plated on fibronectin. These results suggest that TESK1 functions downstream of integrins and plays a key role in integrin-mediated actin reorganization, presumably through phosphorylating and inactivating cofilin. We propose that TESK1 and LIM-kinases commonly phosphorylate cofilin but are regulated in different ways and play distinct roles in actin reorganization in living cells.

One-stage repair of moderately severe hypospadias using a transverse preputial tubularized island flap

BACKGROUND

Transverse preputial tubularized island flap (TPTIF) urethroplasty has been used for the repair of moderately severe hypospadias since Duckett described the procedure in 1980. In spite of the excellent results reported by Duckett, subsequent studies showed high complication rates. A TPTIF procedure modified to reduce the complication rate is presented.

METHODS

Between 1996 and 1997, 13 boys with moderately severe hypospadias were repaired with the TPTIF procedure. Patient age ranged from 10 months to 3 years with an average age of 23 months. To prevent urethrocutaneous fistula, the neourethra was constructed with a two-layer closure and the portion of anastomosis was wrapped between the native urethra and the neourethra with the tissue of the corpus spongiosum.

RESULTS

The moderately severe hypospadias was repaired without complication in 12 of 13 patients. A urethrocutaneous fistula developed at the midshaft of the penis in one patient. No meatal stenosis, urethral stricture or diverticulum developed.

CONCLUSION

Transverse preputial tubularized island flap urethroplasty provided excellent cosmetic and functional results for moderately severe hypospadias, and postoperative complications could be decreased by the two-layer closure of the neourethra and application of the wrapping technique of the proximal anastomosed portion with corpus spongiosum tissue.

The fibril structure of type V collagen triple-helical domain

Although the triple-helical structure of fibrillar collagen is regarded in general as being quite similar, each type of collagen molecule has inherent characteristics in the triple-helical domain. Few studies have ever been performed in terms of the aggregate structure of the triple-helical domain of fibrillar collagen. Reconstituted aggregates from the purified triple-helical domain of each type of fibrillar collagen might amplify the subtle differences in the structural characteristics of each type of collagen molecule. In this study, the reconstituted aggregate structure of pepsin-treated type V collagen (type Vp collagen), that is, virtually its triple-helical domain was characterized by transmission electron microscopy. Pepsin-treated type I (type Ip) and type II (type IIp) collagen were compared with type Vp collagen. Unique features of the aggregate structure of the triple-helical domain of the type V collagen can be summarized as follows:These results suggested that the lateral packing of the triple-helical domain of type V collagen is determined by its molecular structure. The characteristics of type Vp collagen fibrils might be explained by their characteristic amino acid composition. A significant feature of the triple-helical domain of type V collagen is the high content of glycosylated hydroxylysine residues. Molecular model building of the collagenous structure suggests that a change in surface roughness is conspicuous by incorporating the glycosylated hydroxylysine residues. More than a ten-fold content of bulky glycosylated hydroxylysine residues in type V collagen compared to that of type I might have a significant influence on both the intermolecular and interfibrillar interactions of the triple-helical domain of type V collagen molecule.

Phosphorylation of cofilin by LIM-kinase is necessary for semaphorin 3A-induced growth cone collapse

Semaphorin 3A is a chemorepulsive axonal guidance molecule that depolymerizes the actin cytoskeleton and collapses growth cones of dorsal root ganglia neurons. Here we investigate the role of LIM-kinase 1, which phosphorylates an actin-depolymerizing protein, cofilin, in semaphorin 3A-induced growth cone collapse. Semaphorin 3A induced phosphorylation and dephosphorylation of cofilin at growth cones sequentially. A synthetic cell-permeable peptide containing a cofilin phosphorylation site inhibited LIM-kinase in vitro and in vivo, and essentially suppressed semaphorin 3A-induced growth cone collapse. A dominant-negative LIM kinase, which could not be activated by PAK or ROCK, suppressed the collapsing activity of semaphorin 3A. Phosphorylation of cofilin by LIM-kinase may be a critical signaling event in growth cone collapse by semaphorin 3A.

Sociomedical aspects of epileptic patients: their employment and marital status

We examined the employment and marital status of adult patients with epilepsy who did not have mental retardation and who had been treated at Hirosaki University Hospital, Hirosaki, Japan, for more than 5 years. The present study included 278 patients (142 males and 136 females) ranging from 20 to 60 years of age. We investigated the occupational status of the subjects and found that 168 had permanent jobs, but 41 patients were unemployed at the time of this survey. The proportion of the patients whose seizures were controlled at the time of this survey was 68% (114/168) in the group having permanent jobs, and 22% (9/41) in the unemployed group. Forty cases answered that they had resigned from their jobs due to occurrence of epileptic seizures. Of these patients, 13 were dismissed and 27 resigned voluntarily due to the potential for seizures. As to relationship between jobs and neuropsychiatric complications, the incidence of a past history of psychotic states in the unemployed group was significantly higher than that in the employed group. As to marital status, 13 males and 16 females (n = 29) had experienced divorce. Seven cases (two males and five females) had answered that epilepsy had been the reason for their divorce. We conclude that epilepsy or epileptic seizures have various negative effects on the patient's social life.

Thrombin-induced p38 mitogen-activated protein kinase activation is mediated by epidermal growth factor receptor transactivation pathway

Thrombin is a potent mitogen for vascular smooth muscle cells (VSMC) and has been implicated its pathogenic role in vascular remodelling. However, the signalling pathways by which thrombin mediates its mitogenic response are not fully understood. We have previously reported that thrombin activates p38 mitogen-activated protein kinase (p38 MAPK) by a tyrosine kinase-dependent mechanism, and that p38 MAPK has a role in thrombin-induced mitogenic response in rat VSMC. In the present study, we examine the involvement of epidermal growth factor (EGF) receptor in thrombin-induced p38 MAPK activation. We found that thrombin induced EGF receptor tyrosine phosphorylation (transactivation) in A10 cells, a clonal VSMC cell line. A selective inhibitor of EGF receptor kinase (AG1478) inhibited the p38 MAPK activation in a dose-dependent manner, whereas it had no effect on the response to platelet-derived growth factor (PDGF). EGF receptor phosphorylation induced by thrombin was inhibited by BAPTA-AM and GF109203X, which suggest a requirement for intracellular Ca(2+) increase and protein kinase C. We next examined the effect of AG1478 on thrombin-induced DNA synthesis. AG1478 inhibited thrombin-induced DNA synthesis in a dose-dependent manner. In contrast, PDGF-induced DNA synthesis was not affected by AG1478. In conclusion, these data suggest that the EGF receptor transactivation and subsequent p38 MAPK activation is required for thrombin-induced proliferation of VSMC.

Prevention of hepatitis C virus infection in a chimpanzee by vaccination and epitope mapping of antiserum directed against hypervariable region 1

We previously reported on a chimpanzee immunized with both putative envelope glycoproteins (E1 and E2) of hepatitis C virus (HCV), strain HCV-N2, and synthetic peptides of hypervariable region 1 (HVR1) of a different isolate, HCV-#6. The chimpanzee showed complete protection against HCV-#6 infection only when the titer of anti-HVR1 increased, suggesting that an immune response to the HVR1 is more essential in protecting a chimpanzee from HCV infection than an immune response to E1 and E2. In this study, we immunized this chimpanzee with only synthetic HVR1 peptides after anti-E1 and anti-E2 antibody levels dropped and then rechallenged with 10 infectious chimpanzee doses of HCV. The immunized animal was protected, and neutralization of HCV with the antiserum from the protected animal was achieved by inoculating another chimpanzee with HCV preneutralized by this antiserum mixture. Epitope analysis of HVR1 by Pin-ELISA using this antiserum seemed to demonstrate that the antibody response was directed mainly against the C terminus of HVR1. Moreover, our results showed that, if a part of the sequences was conserved, a broad cross-reactivity of the antiserum could be observed, even if amino-acid sequences in this epitope were substituted for those of other HCV strains.

Thrombin activates p38 mitogen-activated protein kinase in vascular smooth muscle cells

Thrombin is a potent mitogen for vascular smooth muscle cells. However, the signaling pathways by which thrombin mediates its mitogenic response are not fully understood. The ERK (extracellular signal-regulated protein kinase) and JNK (c-Jun N-terminal kinase) members of the mitogen-activated protein kinase (MAPK) family are reported to be activated by thrombin. We have investigated the response to thrombin of another member of the MAPK family, p38 MAPK, which has been suggested to be activated by both stress and inflammatory stimuli in vascular smooth muscle cells. We found that thrombin induced time- and dose-dependent activation of p38 MAPK. Maximal stimulation of p38 MAPK was observed after a 10-min incubation with 1 unit ml(-1) thrombin. GF109203X, a protein kinase C inhibitor, and prolonged treatment with phorbol 12-myristate 13-acetate partially inhibited p38 MAPK activation. A tyrosine kinase inhibitor, genistein, also inhibited p38 MAPK activation in a dose-dependent manner. p38 MAPK activation was inhibited by overexpression of betaARK1ct (beta-adrenergic receptor kinase I C-terminal peptide). p38 MAPK activation was also inhibited by expression of dominant-negative Ras, not by dominant-negative Rac. We next examined the effect of a p38 MAPK inhibitor, SB203580, on thrombin-induced proliferation. SB203580 inhibited thrombin-induced DNA synthesis in a dose-dependent manner. These results suggest that thrombin activates p38 MAPK in a manner dependent on Gbetagamma, protein kinase C, a tyrosine kinase, and Ras, that p38 MAPK has a role in thrombin-induced mitogenic response in the cells.

CD45 is required for CD40-induced inhibition of DNA synthesis and regulation of c-Jun NH2-terminal kinase and p38 in BAL-17 B cells

Stimulation of B cell antigen receptor (BCR) may induce proliferation, differentiation, or apoptosis, depending upon the maturational stage of the cell and the presence or absence of signals transmitted via coreceptors. One such signal is delivered via CD40; for instance, ligation of CD40 rescues B cells from BCR-induced apoptosis. Here we show that, in contrast to WEHI-231 cells, CD40 ligation did not reverse BCR-induced growth inhibition in the BAL-17 mature B cell line and CD40 ligation itself inhibited proliferation. This inhibitory signaling was not observed in CD45-deficient cells. Further analyses demonstrate that transfection of dominant-negative form of SEK1 or treatment with SB203580 strongly reduced CD40-induced inhibition of BAL-17 proliferation, suggesting a requirement for c-Jun NH2-terminal kinase and p38 in CD40-induced inhibition of proliferation. Interestingly, CD40-initiated activation of c-Jun NH2-terminal kinase and p38 was enhanced and sustained in CD45-deficient cells, and these phenotypes were reversed by transfecting CD45 gene. However, CD40-mediated induction of cell surface molecules was not affected in CD45-deficient cells. Taken collectively, these results suggest that CD45 exerts a decisive effect on selective sets of CD40-mediated signaling pathways, dictating B cell fate.