Induction of Calcification in MC3T3-E1 Cells by Inorganic Polyphosphate

Relatively large amounts of inorganic polyphosphate [poly(P)] (400 μM) have been found in normal osteoblasts. The effect of poly(P) with an average chain length of 65 phosphate residues on cell calcification was therefore investigated with the use of MC3T3-E1 cells. Expression of both osteopontin and osteocalcin was induced by poly(P) (0.1 ~ 1 mM), and cells treated with poly(P) were strongly stained by alizarin red. In addition, the level of alkaline phosphatase activity induced in poly(P)-treated cells was two-fold higher than that in either orthophosphate-treated or control cells but not higher than that in cells treated with β-glycerophosphate and ascorbic acid. In contrast, however, polyphosphatase activities were activated by poly(P) treatment to levels up to six-fold greater than that in controls. MC3T3-E1 cells may utilize poly(P) as a phosphate source for calcification rather than phosphate sources that are mainly produced by ALPase. Poly(P)-dependent induction of polyphosphatase activities may therefore promote calcification in MC3T3-E1 cells.

Segmental Distribution of Vasa Vasorum to the Canine Abdominal Vena Cava: A Possible Correlation with its Embryogenesis

The segment of the male canine abdominal vena cava (AVC) between the liver and the renal veins receives vasa vasorum from the right phrenicoabdom inal artery, while the infrarenal segment of AVC does from the right testicular artery. These facts were confirmed by both macroscopic observation with dye injection into the arteries and measurement of contractile responses of the segments in vivo by the method with intravascular cuffs. The segmental dis tribution of vasa vasorum from arteries of the right side may closely correlate with the embryogenesis of the vein.

An anomalous dog with totally inverted viscera, which we found during our study, exhibited another anomaly of AVC: It had the segment of AVC between the liver and the renal veins at the left side of the aorta and the infrarenal segment at the right. This anomaly shows that AVC is composed with at least two segments which is formed separately during its embryogenesis and may support our hypothesis.

Polymerization of room-temperature ionic liquid monomers by electron beam irradiation with the aim of fabricating three-dimensional micropolymer/nanopolymer structures

A novel method for fabricating microsized and nanosized polymer structures from a room-temperature ionic liquid (RTIL) on a Si substrate was developed by the patterned irradiation of an electron beam (EB). An extremely low vapor pressure of the RTIL, 1-allyl-3-ethylimidazolium bis((trifluoromethane)sulfonyl)amide, allows it to be introduced into the high-vacuum chamber of an electron beam apparatus to conduct a radiation-induced polymerization in the nanoregion. We prepared various three-dimensional (3D) micro/nanopolymer structures having high aspect ratios of up to 5 with a resolution of sub-100 nm. In addition, the effects of the irradiation dose and beam current on the physicochemical properties of the deposited polymers were investigated by recording the FT-IR spectra and Young's modulus. Interestingly, the overall shapes of the obtained structures were different from those prepared in our recent study using a focused ion beam (FIB) even if the samples were irradiated in a similar manner. This may be due to the different transmission between the two types of beams as discussed on the basis of the theoretical calculations of the quantum beam trajectories. Perceptions obtained in this study provide facile preparation procedures for the micro/nanostructures.

Abstract P6-11-13: Phase I Study of Combined S-1 Plus Weekly Paclitaxel Therapy in Patients with Metastatic Breast Cancer

Introduction: S-1, a novel anticancer compound, contains tegafur, a prodrug of fluorouracil (FU), 5-chloro-2.4-dihydroxypyridine, which prevents FU degradation, and potassium oxonate, which prevents drug-induced diarrhea, has a broad spectrum of activity against gastric, colorectal, head & neck, and breast cancers. While combined S-1 with cisplatin or paclitaxel (PAC) therapy is feasible and highly active against gastrointestinal cancer, the feasibility in breast cancer patients has not yet been clarified. We conducted a phase I study of combined S-1 plus weekly PAC therapy (S-1/PAC) to determine the maximum tolerated dose (MTD), recommended dose (RD) and dose-limiting toxicities (DLT) in patients (pts) with HER2-negative, taxane-naïve metastatic breast cancer (MBC).

Methods: S-1 was administered orally from day 1 through day 14 and PAC was administered intravenously on days 1, 8 and 15 of each 28-day cycle. Since S-1 is prescribed at the dose of 80mg/m2 in monotherapy, the primary dose levels (level 1) were set at 65 and 70mg/m2, respectively. The final dose (level 3) was set at 80mg/m2 for each drugs. DLT was defined over 2 cycles.

Results: Ten MBC pts were enrolled in the study. No DLTs were documented. Although grade 1 or 2 adverse events were seen in all pts, no cases of febrile neutropenia or Gr 4 neutropenia were observed. Of the 8 evaluable pts, 3 pts achieved partial response and 4 pts had stable disease.

Conclusion: Based on the results of this study, RD was determined to be 80mg/m2 for either drugs. We conclude that S-1/PAC was well-tolerated and highly active against HER2-negative MBC.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-11-13.

Inorganic Polyphosphate Induces Osteoblastic Differentiation

Inorganic polyphosphate [Poly(P)] is especially prevalent in osteoblasts. We tested the hypothesis that Poly(P) stimulates osteoblastic differentiation and polyphosphate metabolism for bone formation. The osteoblast-like cell line, MC 3T3-E1, was cultured with Poly(P), and gene expression was evaluated by real-time reverse-transcription polymerase chain-reaction. Phosphatase activity and extracellular matrix mineralization were also determined. The role of Poly(P) was assessed in a beagle dog alveolar bone regeneration model. Poly(P) increased osteocalcin, osterix, bone sialoprotein, and tissue non-specific alkaline phosphatase gene expression, with a high level of end-polyphosphatase activity, resulting in low-chain-length Poly(P), inorganic pyrophosphate, and inorganic phosphate production. MC3T3-E1 cells differentiated into mature osteoblasts and showed expression of ectonucleotide pyrophosphatase phosphodiesterase 1, while mouse progressive ankylosis gene expression remained unchanged. Promotion of alveolar bone regeneration was observed in Poly(P)-treated beagle dogs. These findings suggest that Poly(P) induces osteoblastic differentiation and bone mineralization, and acts as a resource for mineralization.

Tuning of the fluorescence wavelength of CdTe quantum dots with 2 nm resolution by size-selective photoetching

Photoetching of CdTe nanocrystals was applied to thiol-capped CdTe quantum dots (QDs) to control their fluorescence wavelength. CdTe QDs with a high quantum yield (49%) were synthesized in aqueous solution, and they were successfully photoetched in strong alkaline (pH = 13.5) conditions. When monochromatic light was used, size-selective photoetching could be conducted; the photoetching proceeded until the band gap energy of the CdTe QDs increased to the energy corresponding to the wavelength of the irradiating light. As a result, a good linear relationship was obtained between the wavelength of the irradiating light and that of the fluorescence peak. The resulting CdTe QDs exhibited a fluorescence peak with an FWHM value as small as 23.5 nm, indicating preparation of highly monodispersed nanocrystals. The high quantum yield (ca. 45%) was maintained after the photoetching. Very fine tuning of the fluorescence wavelength with 2 nm resolution was achieved by changing the wavelength of the irradiating light by 2 nm. Theoretical calculation of the quantum size effects (effective mass approximation) predicts that a difference in the band gap fluorescence wavelength of 2 nm corresponds to a change in particle diameter of ca. 0.02 nm.

Soft-copy reading in digital mammography of mass: diagnostic performance of a 5-megapixel cathode ray tube monitor versus a 3-megapixel liquid crystal display monitor in a diagnostic setting

BACKGROUND

Liquid crystal display (LCD) monitors and cathode ray tube (CRT) monitors are currently the two most common types used in digital mammography systems. The appropriate selection of a monitor is very important and requires balancing the monitor's performance and its cost. A previous study of soft-copy reading in digital mammography of microcalcifications showed that 3-megapixel (M) LCD monitors were similar in diagnostic performance to 5M CRT monitors in a diagnostic setting.

PURPOSE

To compare 5M CRT monitors with 3M LCD monitors for soft-copy reading of digital mammography of a mass in a diagnostic setting.

MATERIAL AND METHODS

Seventy mass lesions having undergone either breast biopsies or definitive surgery (46 malignant and 24 benign) and 30 normal cases were recruited into the study. The median size of the lesions was 16 mm (range 7-20 mm). The digital mammograms in the 100-case set were assigned to two blocks, block A (50 cases) and block B (50 cases), for 5M CRT and 3M LCD monitors. A single radiologist read all 100 cases with both types of monitors, starting with the images in block A on the 5M CRT monitors and then the images in block B on the 3M LCD monitors. The radiologist analyzed the soft-copy images on 5M CRT and 3M LCD monitors with 5 months between the interpretations to reduce the effects of learning and memory. Again, the reader started with the images in block A on the 3M LCD monitors and then read the images in block B on the 5M CRT monitors. A five-point rating scale for the probability of malignancy was used for interpreting the soft-copy mammograms. The mass descriptor was scored on a six-point scale. Breast density was scored on a four-point scale. The positive predictive value (PPV) and negative predictive value (NPV) were calculated based on the criteria of the Breast Imaging Reporting and Data System. The interpretation time was also measured.

RESULTS

No significant difference was observed in the probability of malignancy (P=1), mass descriptor (P=0.317), and breast density (P=0.739). The PPV and NPV of soft-copy reading on the 5M CRT monitors were 91% (42/46) and 94% (51/54), respectively, identical to the results using 3M LCD monitors. The total interpretation time averaged 62 s for the 5M CRT monitors and 60 s for the 3M LCD monitors (P<0.0001).

CONCLUSION

Soft-copy reading of a digital mammography of mass with 3M LCD monitors was similar in diagnostic performance to 5M CRT monitors in this study. On the basis of the results of this and a previous study, 3M LCD monitors can replace 5M CRT monitors without any loss in the ability to diagnose digital mammograms.

Inorganic polyphosphate: a possible stimulant of bone formation

Inorganic polyphosphates [Poly(P)] are often distributed in osteoblasts. We undertook the present study to verify the hypothesis that Poly(P) stimulates osteoblasts and facilitates bone formation. The osteoblast-like cell line MC 3T3-E1 was cultured with Poly(P), and gene expression and potential mineralization were evaluated by reverse-transcription polymerase chain-reaction. Alkaline phosphatase activity, von Kossa staining, and resorption pit formation analyses were also determined. The potential role of Poly(P) in bone formation was assessed in a rat alveolar bone regeneration model. Poly(P) induced osteopontin, osteocalcin, collagen 1alpha, and osteoprotegerin expression and increased alkaline phosphatase activity in MC 3T3-E1 cells. Dentin slice pit formation decreased with mouse osteoblast and bone marrow macrophage co-cultivation in the presence of Poly(P). Promotion of alveolar bone regeneration was observed locally in Poly(P)-treated rats. These findings suggest that Poly(P) plays a role in osteoblastic differentiation, activation, and bone mineralization. Thus, local poly(P) delivery may have a therapeutic benefit in periodontal disease.

Soft-copy reading in digital mammography of microcalcifications: diagnostic performance of a 5-megapixel cathode ray tube monitor versus a 3-megapixel liquid crystal display monitor in a clinical setting

BACKGROUND

A recent study using dedicated contrast-detail phantoms showed that the image quality of a 3-megapixel (M) monitor can approach that of a 5M monitor in digital mammography.

PURPOSE

To compare a 5M cathode ray tube (CRT) monitor with a 3M liquid crystal display (LCD) monitor for soft-copy reading of digital mammography of microcalcifications in a clinical setting.

MATERIAL AND METHODS

100 screen-detected microcalcification lesions (34 malignant and 66 benign) without mass that had been evaluated with 11-gauge stereotactic vacuum-assisted breast biopsy or definitive surgery were recruited into the study. One radiologist analyzed the soft-copy mammograms on a 5M CRT monitor and a 3M LCD monitor with 5 months between interpretations and scored the likelihood of malignancy and calcification distribution on a five-point scale. Calcification morphology and breast density were scored on a four-point scale. Positive predictive value (PPV) and negative predictive value (NPV) were calculated on the basis of a Breast Imaging Reporting and Data System. The interpretation time was also measured.

RESULTS

There was no significant difference in the likelihood of malignancy (P = 0.655), calcification morphology (P = 0.168), calcification distribution (P = 0.11), and breast density (P = 0.0608). The PPV and NPV of soft-copy reading on the 5M CRT monitor was 57% (30/53) and 91% (43/47), respectively, identical to the results using the 3M LCD monitor. The total interpretation time averaged 88 s for the 5M CRT monitor and 67 s for the 3M LCD monitor (P<0.0001).

CONCLUSION

Soft-copy reading of a digital mammography of microcalcifications with a 3M LCD monitor was similar in diagnostic performance to a 5M CRT monitor in this study.

Preoperative computed tomography-guided percutaneous hookwire localization of metallic marker clips in the breast with a radial approach: initial experience

BACKGROUND

Hookwire localization is the current standard technique for radiological marking of nonpalpable breast lesions. Stereotactic directional vacuum-assisted breast biopsy (SVAB) is of sufficient sensitivity and specificity to replace surgical biopsy. Wire localization for metallic marker clips placed after SVAB is needed.

PURPOSE

To describe a method for performing computed tomography (CT)-guided hookwire localization using a radial approach for metallic marker clips placed percutaneously after SVAB.

MATERIAL AND METHODS

Nineteen women scheduled for SVAB with marker-clip placement, CT-guided wire localization of marker clips, and, eventually, surgical excision were prospectively entered into the study. CT-guided wire localization was performed with a radial approach, followed by placement of a localizing marker-clip surgical excision. Feasibility and reliability of the procedure and the incidence of complications were examined.

RESULTS

CT-guided wire localization surgical excision was successfully performed in all 19 women without any complications. The mean total procedure time was 15 min. The median distance on CT image from marker clip to hookwire was 2 mm (range 0-3 mm).

CONCLUSION

CT-guided preoperative hookwire localization with a radial approach for marker clips after SVAB is technically feasible.

New class of dynamics in concentrated polymer gels

We show that concentrated poly(methyl methacrylate) solution exhibits a new class of coupled dynamics, which can be regarded as an intermediate between the collective diffusion of solutions and the structural relaxations of glasses. This class of dynamics have a relaxation rate that is directly proportional to the wave vector. The transition from diffusive to coupled collective dynamics occurs at smaller length scales with increasing polymer concentration and decreasing temperature. The experimental observations can be understood by considering the contributions from physical cross-links interconnected by stiff polymer segments.

Overeruption without root exposure of third molars and periodontal health in the mandible

Bone formation is seen around the third molar even when the tooth is exposed to the oral environment due to overeruption. To determine if overeruption of the third molar with or without root exposure is related to the status of the exposure of other teeth in the mandible, using orthopantomographs, 424 third molars were studied in 371 patients who were over 41 years of age. The rate of overeruption and root exposure in third molars was measured, and its relationship to the number of teeth lost and the rate of root exposure in other teeth in the mandible was analyzed. Tooth loss in the group of third molars with overeruption without root exposure was greater than in that without overeruption or root exposure in men, whereas the relationship was not seen in women. We found that root exposures of other teeth in the group of third molars with overeruption without root exposure were significantly smaller than in those with root exposure in both genders. Third molars with overeruption without root exposure, in which bone formation was easy to observe for radiographic diagnosis, were correlated with periodontal health in the mandible, suggesting a component of precision determination for predicting resistance to periodontitis.

Power laws in polymer solution dynamics

The dynamical screening length xi(h) in semidilute to highly concentrated polymer solutions of poly(methyl methacrylate) in propylene carbonate has been examined using photon correlation spectroscopy and pulsed field gradient nuclear magnetic resonance. A crossover between different concentration dependent regimes, xi(h) approximately phi(-alpha), where alpha is found to be approximately 0.5, approximately 1, and approximately 2, is observed when the local viscosity is taken into account. Here phi is the volume fraction of polymer in the solution. Well-defined crossovers between alpha=0.5 and alpha=1 corresponding to a transition from a marginal solvent to a theta solvent behavior have been predicted to occur due to the reduction of excluded-volume effects between the spatially correlated polymer segments with increasing polymer volume fraction. However, a clear experimental validation of the crossover has never been presented before. The third regime (alpha approximately 2) is observed in the highly concentrated region where the static screening length is comparable to the persistence length of the polymer. The observation indicates that the rigid rod model previously used to describe concentrated solutions is an oversimplification valid only in the very high concentration limit. The obtained results at high concentrations are discussed in the frame of a simple physical model where segments at the persistence length scale are treated as flexible rodlike segments.

Relationship of the hyoid bone and posterior surface of the tongue in prognathism and micrognathia

In order to study relationship of the hyoid bone and posterior surface of the tongue in prognathism and micrognathia, we focused on the effect of the tongue on the upper airway lumen in 16 patients with Angle's Class II and 51 patients with Angle's Class III, and assessed the position of the hyoid, the depth from the posterior surface of the tongue, from the bottom of the vallecula and from hyoid bone to the posterior pharyngeal wall using lateral cephalograms. We were able to assess significant correlations between the posterior surface of the tongue and hyoid position in Angle's Class III. However, we found no association between them in Angle's Class II. This could be an adaptive feature of the genioglossus in response to hyoid localization to serve a compensatory role to prevent respiratory impairment in micrognathia at risk of apnoea.

Autoimmune thyroid disease accompanied by recurring episodes of painful thyroid ameliorated by thyroidectomy

A 71-yr-old female initially presented with clinical and biochemical hyperthyroidism with high TSH binding inhibitory immunoglobulin (TBII) and anti-thyroid peroxidase antibody (TPOAb) titers. Histological findings of the thyroid revealed hyperplasia with a focal germinal center, indicating Graves' disease and mild focal chronic thyroiditis. Four episodes of painful and tender thyroid occurred over the next 2 yr accompanied by acute inflammatory reactions. The first episode that developed while the patient was in a hyperthyroid state was soon followed by hypothyroidism associated with further increases in anti-thyroglobulin antibody (TGAb) and TPOAb titers. The subsequent 3 episodes occurred during the hypothyroid state, when the TGAb titer progressively increased with each episode. We performed subtotal thyroidectomy to prevent further episodes. Specimens obtained at thyroidectomy showed that extreme fibrosis had replaced the thyroid parenchyma with collapsed follicles and moderate lymphocyte infiltration. No further episodes occurred after thyroidectomy, and during a 3-yr follow-up period, TBII and thyroid-stimulating antibody (TSAb) disappeared and TGAb and TPOAb titers decreased. This case report provides further evidence supporting the notion that thyroid epithelial destruction progresses during relatively short periods of recurrent painful thyroid and that thyroidectomy helps patients affected by this condition that are unresponsive to other treatment strategies.

Comparison between high-resolution helical CT and pathology in breast examination

PURPOSE

To determine whether high-resolution helical CT can show the architectural features of breast carcinomas of non-limited extent (non-BCLE) and to establish the CT characteristic morphology of non-BCLE.

MATERIAL AND METHODS

We prospectively studied high-resolution helical CT of 136 invasive breast carcinomas before breast-conserving surgery. Non-BCLE were defined as ductal carcinomas in situ and invasive carcinomas beyond 1 cm from the edge of the dominant mass. Non-BCLE were defined as positive if enhanced beyond 1 cm from the edge of the focal enhancement on CT. After surgical resection, specimens were sliced in serial sections at 5-mm intervals, and the gross morphology and histology were correlated with the appearance of the preoperative CT lesion images.

RESULTS

Non-BCLE were present in 47 invasive carcinomas. The sensitivity and specificity of non-BCLE evaluation by high-resolution helical CT were 70% and 89%, respectively. The morphology of non-BCLE on CT agreed with histologic findings. The morphological pattern on CT significantly correlated with intraductal tumor density adjacent to invasive tumor.

CONCLUSION

Comparison of high-resolution helical CT with histologic data suggests that demonstration of a non-BCLE morphology can make the CT breast carcinoma local staging more accurate.

Comparison between high-resolution helical CT and pathology in breast examination

PURPOSE

To determine whether high-resolution helical CT can show the architectural features of breast carcinomas of non-limited extent (non-BCLE) and to establish the CT characteristic morphology of non-BCLE.

MATERIAL AND METHODS

We prospectively studied high-resolution helical CT of 136 invasive breast carcinomas before breast-conserving surgery. Non-BCLE were defined as ductal carcinomas in situ and invasive carcinomas beyond 1 cm from the edge of the dominant mass. Non-BCLE were defined as positive if enhanced beyond 1 cm from the edge of the focal enhancement on CT. After surgical resection, specimens were sliced in serial sections at 5-mm intervals, and the gross morphology and histology were correlated with the appearance of the preoperative CT lesion images.

RESULTS

Non-BCLE were present in 47 invasive carcinomas. The sensitivity and specificity of non-BCLE evaluation by high-resolution helical CT were 70% and 89%, respectively. The morphology of non-BCLE on CT agreed with histologic findings. The morphological pattern on CT significantly correlated with intraductal tumor density adjacent to invasive tumor.

CONCLUSION

Comparison of high-resolution helical CT with histologic data suggests that demonstration of a non-BCLE morphology can make the CT breast carcinoma local staging more accurate.

Interleukin (IL)-17 enhances prostaglandin F(2 alpha)-stimulated IL-6 synthesis in osteoblasts

We previously showed that prostaglandin F(2alpha) (PGF(2alpha)) and endothelin-1 (ET-1) induce interleukin (IL)-6 through the activation of protein kinase C-dependent p44/p42 mitogen-activated protein (MAP) kinase in osteoblast-like MC3T3-E1 cells. It has recently been reported that tumor necrosis factor-alpha-induced IL-6 synthesis is amplified by IL-17 in these cells. In the present study, we investigated the effect of IL-17 on the IL-6 synthesis stimulated by PGF(2alpha) in MC3T3-E1 cells. IL-17 significantly enhanced the PGF(2alpha)-induced IL-6 synthesis in a dose-dependent manner in the range between 0.1 and 10 ng/ml. IL-17 also enhanced the IL-6 synthesis stimulated by 12- O -tetradecanoylphorbol-13-acetate, a direct activator of protein kinase C. In addition, IL-17 amplified the IL-6 synthesis induced by ET-1. However, IL-17 hardly affected the phosphorylation of p44/p42 MAP kinase induced by PGF(2alpha) or ET-1. These results strongly suggest that IL-17 enhances the IL-6 synthesis stimulated by PGF(2alpha) as well as ET-1 in osteoblasts, and that the effect is exerted at a point downstream from p44/p42 MAP kinase.

Contrasting effects of midazolam on induction of heat shock protein 27 by vasopressin and heat in aortic smooth muscle cells

We previously showed that vasopressin stimulates the induction of heat shock protein (HSP) 27, a low molecular-weight HSP, through protein kinase C activation in aortic smooth muscle A10 cells. In the present study, we examined the effects of midazolam, an intravenous anesthetic, on the HSP27 induction stimulated by vasopressin, heat, or sodium arsenite (arsenite) in A10 cells. Midazolam inhibited the accumulation of HSP27 induced by vasopressin or 12-O-tetradecanoylphorbol 13-acetate (TPA), a direct activator of protein kinase C. Midazolam also reduced the vasopressin-induced level of the mRNA for HSP27. In contrast, midazolam enhanced the HSP27-accumulation induced by heat or arsenite. Midazolam also enhanced the heat-increased level of the mRNA for HSP27. However, midazolam had no effect on the dissociation of the aggregated form of HSP27 following stimulation by vasopressin, heat, or arsenite. These results suggest that midazolam suppresses vasopressin-stimulated HSP27 induction in vascular smooth muscle cells, and that this inhibitory effect is exerted at a point downstream from protein kinase C. In contrast, midazolam enhanced heat- or arsenite-stimulated HSP27 induction. Thus, midazolam has dual effects on the HSP27 induction stimulated by various stresses in vascular smooth muscle cells.

Mechanism of prostaglandin E2-stimulated heat shock protein 27 induction in osteoblast-like MC3T3-E1 cells

We investigated the effect of prostaglandin E2 (PGE2) on the induction of heat shock protein 27 (HSP27) and HSP70, and the mechanism behind the induction in osteoblast-like MC3T3-E1 cells. PGE2 time-dependently increased the level of HSP27 without affecting the level of HSP70. PGE2 stimulated the accumulation of HSP27 dose-dependently in the range between 10 nM and 10 microM. PGE2 stimulated the increase in the level of the mRNA for HSP27. Staurosporine and calphostin C, inhibitors of protein kinase C (PKC), suppressed the PGE2-induced HSP27 accumulation. The effect of PGE2 on HSP27 accumulation was reduced in the PKC down-regulated cells. BAPTA/AM, a chelator of intracellular Ca2+, or TMB-8, an inhibitor of intracellular Ca2+ mobilization, reduced the accumulation of HSP27 induced by PGE2. Dibutyryl cAMP had little effect on the basal level of HSP27. PGE2 induced the phosphorylation of both p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase. PD98059 and U-0126, inhibitors of the upstream kinase of p44/p42 MAP kinase, reduced the accumulation of HSP27 induced by PGE2. SB203580, a specific inhibitor of p38 MAP kinase, suppressed the HSP27 accumulation induced by PGE2. U-73122, an inhibitor of phospholipase C, and calphostin C reduced the PGE2-induced phosphorylation of both p44/p42 MAP kinase and p38 MAP kinase. These results indicate that PGE2 stimulates the induction of HSP27 through PKC-dependent activations of both p44/p42 MAP kinase and p38 MAP kinase in osteoblasts.

The loss of susceptibility to apoptosis in exudated tissue neutrophils is associated with their nuclear factor-kappa B activation

Tissue neutrophils, human salivary neutrophils donated from healthy subjects and synovial fluid neutrophils collected from patients with rheumatoid arthritis were compared with circulating blood neutrophils. Concomitant treatment of circulating blood neutrophils with tumor necrosis factor-alpha (TNF-alpha) and cycloheximide induced neutrophil apoptosis, whereas the same treatment failed to induce significant apoptosis in salivary and synovial fluid neutrophils. Caspase-3 activation by TNF-alpha was observed in these tissue neutrophils, although its activity was significantly weaker than that in circulating blood neutrophils. In circulating blood neutrophils, TNF-alpha induced activation of nuclear factor-kappa B (NF-kappa B), whereas, in tissue neutrophils, NF-kappa B had been already activated without any stimulation, and no further activation was induced by the treatment with TNF-alpha. Furthermore, while pretreatment of neutrophils with an NF-kappa B inhibitor produced typical apoptotic changes in circulating blood neutrophils, this inhibitor did not produce any morphological apoptotic changes induced by TNF-alpha in tissue neutrophils. These results indicate that neutrophils undergo marked functional changes such as altered sensitivity to apoptosis-inducing stimuli in association with their exudation from blood into tissue, and that NF-kappa B activation is involved in the acquisition of resistance to TNF-alpha-induced apoptosis.

Inhibition by adenylyl cyclase-cAMP system of ET-1-induced HSP27 in osteoblasts

We have previously reported that endothelin-1 (ET-1) stimulates heat shock protein (HSP) 27 induction in osteoblast-like MC3T3-E1 cells and that p38 mitogen-activated protein (MAP) kinase acts at a point downstream from protein kinase C (PKC) in HSP27 induction. In the present study, we investigated the effect of the adenylyl cyclase-cAMP system on ET-1-stimulated induction of HSP27 in MC3T3-E1 cells. Dibutyryl-cAMP (DBcAMP) dose dependently inhibited the HSP27 accumulation stimulated by ET-1. Forskolin and cholera toxin significantly suppressed the ET-1-stimulated accumulation of HSP27. However, dideoxyforskolin, a forskolin derivative that does not activate cAMP, failed to suppress the ET-1-induced HSP27 accumulation. Forskolin reduced the p38 MAP kinase phosphorylation induced by ET-1 or 12-O-tetradecanoylphorbol-13-acetate (TPA). PGE(1), an extracellular agonist that activates cAMP production, reduced the ET-1-induced HSP27 accumulation. In addition, the phosphorylation of p38 MAP kinase induced by ET-1 or TPA was suppressed by PGE(1). Forskolin, DBcAMP, and PGE(1) suppressed the ET-1-stimulated increase in the mRNA level for HSP27. These results indicate that the adenylyl cyclase-cAMP system has an inhibitory role in ET-1-stimulated HSP27 induction in osteoblasts and that the effect is exerted at the point between PKC and p38 MAP kinase in osteoblasts.

Intrahepatic cholangiocarcinoma arising 10 years after the excision of congenital extrahepatic biliary dilation

A 52-year-old woman was found to have a liver tumor during treatment for a liver abscess. The tumor was diagnosed as intrahepatic cholangiocarcinoma by closer examinations, including a percutaneous needle biopsy. Ten years previously, she had undergone excision of a choledochal cyst, with reconstruction by Roux-en-Y hepaticojejunostomy, as treatment for Todani's type Ia congenital biliary dilation, which had been confined only to the extrahepatic bile duct. The significant association between congenital biliary dilation and hepatobiliary malignancies is well known. Some patients have been reported to develop biliary cancer long after the excision of the entire extrahepatic bile duct and hepaticoenterostomy. However, in these patients, the development mostly took place in the remnant choledochal cyst, the anastomotic site, or in the dilated intrahepatic bile duct of Todani's type IV-A congenital biliary dilation. The development of intrahepatic cholangiocarcinoma after operation has not been reported previously in a patient with Todani's type I congenital biliary dilation. This case suggests that the entire biliary tree may have a high risk of field cancerization, even in extrahepatic congenital biliary dilation.

Trifluoromethyl ketone-based inhibitors of apoptosis in cerebellar granule neurons

A variety of aromatic trifluoromethyl ketone derivatives has been studied as inhibitors of apoptosis in cerebellar granule neurons (CGNs). Among them, alpha-trifluoromethyl diketone (2) and benzyl trifluoromethyl ketone (11) were found to be apoptosis inhibitors which can prevent a neurodegenerative disease. Compounds 2 and 11 showed neuroprotection effect on low K+-induced apoptosis in CGNs. Furthermore, these compounds effectively suppressed DNA fragmentation accompanied with apoptosis. The neuroprotection mode of 2 and 11 was not related to inhibition of caspase-3.

Measurement of flecainide in hair as an index of drug exposure

We report a method for measuring the concentration of flecainide in hair. An animal study, in which flecainide (1, 5, and 10 mg/kg/day) was orally administered for 1, 2, and 3 weeks to pigmented rats, showed that flecainide concentration in rat hairs newly regrown after administration significantly correlated with both the daily dose and the dosing period. The part of hair containing flecainide continued to grow upward, retaining the drug within the hair structure that had been formed at the time of drug exposure. Flecainide was also determined in human scalp hairs collected from patients treated with flecainide. The drug content of white hairs was much less than that black hairs collected from the same rats and subjects, suggesting the determinant effect of hair pigment on flecainide accumulation in hair. These findings suggest that the analysis of flecainide in hair may be useful for assessing exposure to drug qualitatively.

Involvement of p38 MAP kinase in TGF-beta-stimulated VEGF synthesis in aortic smooth muscle cells

Although it is known that transforming growth factor (TGF)-beta induces vascular endothelial growth factor (VEGF) synthesis in vascular smooth muscle cells, the underlying mechanisms are still poorly understood. In the present study, we examined whether the mitogen-activated protein (MAP) kinase superfamily is involved in TGF-beta-stimulated VEGF synthesis in aortic smooth muscle A10 cells. TGF-beta stimulated the phosphorylation of p42/p44 MAP kinase and p38 MAP kinase, but not that of SAPK (stress-activated protein kinase)/JNK (c-Jun N-terminal kinase). The VEGF synthesis induced by TGF-beta was not affected by PD98059 or U0126, specific inhibitors of the upstream kinase that activates p42/p44 MAP kinase. We confirmed that PD98059 or U0126 did actually suppress the phosphorylation of p42/p44 MAP kinase by TGF-beta in our preparations. PD169316 and SB203580, specific inhibitors of p38 MAP kinase, significantly reduced the TGF-beta-stimulated synthesis of VEGF (each in a dose-dependent manner). PD169316 or SB203580 attenuated the TGF-beta-induced phosphorylation of p38 MAP kinase. These results strongly suggest that p38 MAP kinase plays a part in the pathway by which TGF-beta stimulates the synthesis of VEGF in aortic smooth muscle cells.

AlphaB-crystallin, a low-molecular-weight heat shock protein, acts as a regulator of platelet function

It has recently been reported that alphaB-crystallin, a low-molecular-weight heat shock protein, may be released from cells by mechanical stretch. We investigated a physiological role of alphaB-crystallin in platelet function. AlphaB-crystallin inhibited platelet aggregation induced by thrombin or botrocetin in hamsters and humans. These platelets had specific binding sites for alphaB-crystallin. Moreover, alphaB-crystallin significantly reduced thrombin-induced Ca2+ influx and phosphoinositide hydrolysis by phospholipase C in human platelets. Additionally, plasma levels of alphaB-crystallin were markedly elevated in cardiomyopathic hamsters. Levels of alphaB-crystallin in vessel walls after endothelial injury were markedly reduced. Therefore, our results suggest that alphaB-crystallin, which is discharged from vessel walls in response to endothelial injury, acts intercellularly as a regulator of platelet function.

Differential uptake of grepafloxacin by human circulating blood neutrophils and those exudated into tissues

The uptake of the antimicrobial quinolone agent, grepafloxacin, both by human circulating blood neutrophils and by those exudated into tissues, was evaluated in vitro by comparing the intracellular drug concentrations. In circulating blood neutrophils, the uptake of grepafloxacin was rapid and saturable at 37 degrees C. The uptake of grepafloxacin into circulating blood neutrophils was reduced by lowering the environmental temperature or by the presence of metabolic inhibitors, suggesting the involvement of an active transport mechanism. Furthermore, the uptake of grepafloxacin by tissue (salivary) neutrophils was also partially temperature-dependent and was significantly greater than that by circulating blood neutrophils, i.e. exudation of neutrophils into tissue results in a markedly enhanced transport mechanism for grepafloxacin. This phenomenon may be related to the higher defense activity against infection seen in exudated tissue neutrophils.

Staging of palpable T1-2 invasive breast cancer with helical CT

BACKGROUND

The purpose of this study was to evaluate the accuracy of contrast-enhanced high resolution helical computed tomography (CT) for assessing locoregional staging of palpable T1-2 invasive breast cancer.

METHODS

Helical CT studies of 156 lesions from 156 patients with invasive breast cancer before breast-conserving surgery were examined. A lesion was defined as positive if focal enhancement was detected by CT within 100 seconds after contrast material administration. After resection, tumors were histopathologically mapped and comparison made with the extent of contrast enhancement.

RESULTS

Helical CT enabled detection of all 156 index tumors. CT enabled detection of 28 of 43 multifocal lesions (65%) and five of five multicentric lesions (100%). In 24 of 33 lesions (73%), CT revealed additional cancers not seen on mammography. The extent of tumor significantly correlated with CT measurements (r=0.76, p<0.0001).

CONCLUSION

Helical CT of the breast is an accurate preoperative imaging modality for assessing the locoregional staging of T1-2 invasive breast cancer.

Activation of p44/p42 mitogen-activated protein kinase limits triiodothyronine-stimulated alkaline phosphatase activity in osteoblasts

It has been shown that thyroid hormone stimulates the activity of alkaline phosphatase, a marker of mature osteoblast phenotype, in osteoblasts. In the present study, we investigated whether p44/p42 mitogen-activated protein (MAP) kinase is involved in the thyroid hormone-stimulated alkaline phosphatase activity in osteoblast-like MC3T3-E1 cells. Triiodothyronine (T(3)) markedly induced the phosphorylation of p44/p42 MAP kinase. PD98059 and U0126, inhibitors of the upstream kinase that activates p44/p42 MAP kinase, significantly enhanced the T(3)-induced alkaline phosphatase activity in a dose-dependent manner. The phosphorylation of p44/p42 MAP kinase induced by T(3) was reduced by U0126. These results strongly suggest that p44/p42 MAP kinase takes part in the thyroid hormone-stimulated alkaline phosphatase activity in osteoblasts and that p44/p42 MAP kinase plays an inhibitory role in the thyroid hormone-effect.

p38 mitogen-activated protein (MAP) kinase but not p44/p42 MAP kinase is involved in prostaglandin E1-induced vascular endothelial growth factor synthesis in osteoblasts

We investigated the mechanism underlying vascular endothelial growth factor (VEGF) synthesis stimulated by prostaglandin E1 (PGE1) in osteoblast-like MC3T3-E1 cells. PGE1 induced the phosphorylation of both p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase. SB203580, a specific inhibitor of p38 MAP kinase, inhibited the PGE1-stimulated VEGF synthesis as well as PGE1-induced phosphorylation of p38 MAP kinase. PD98059, an inhibitor of the upstream kinase that activates p44/p42 MAP kinase, which reduced the PGE1-induced phosphorylation of p44/p42 MAP kinase, had little effect on the VEGF synthesis stimulated by PGE1. AH-6809, an antagonist of the subtypes of the PGE receptor, EP1 and EP2, or SC-19220, an antagonist of EP1 receptor, did not inhibit the PGE1-induced VEGF synthesis. H-89, an inhibitor of cAMP-dependent protein kinase, and SQ22536, an inhibitor of adenylate cyclase, reduced the VEGF synthesis induced by PGE1. Cholera toxin, an activator of G(s), and forskolin, an activator of adenylate cyclase, induced VEGF synthesis. SB203580 and PD169316, another specific inhibitor of p38 MAP kinase, reduced the cholera toxin-, forskolin- or 8bromo-cAMP-stimulated VEGF synthesis. However, PD98059 failed to affect the VEGF synthesis stimulated by cholera toxin, forskolin or 8-bromoadenosine-3',5'-cyclic monophosphate (8bromo-cAMP). SB203580 reduced the phosphorylation of p38 MAP kinase induced by forskolin or 8bromo-cAMP. These results strongly suggest that p44/p42 MAP kinase activation is not involved in the PGE1-stimulated VEGF synthesis in osteoblasts but that p38 MAP kinase activation is involved.

Photochemically induced equilibrium dysfunction in the hamster model with evaluation by means of a new globe rotatory test system

Thrombosis in the inner ear is regarded as one of the causes of equilibrium dysfunction. We have established an experimental thrombosis model by producing a photochemical reaction between rose bengal and green light, and have evaluated the dysfunction with a new rotatory test system. Hamsters were treated with tissue-type plasminogen activator (tPA) in doses of 0, 0.13, 0.26, and 0.52 mg/kg. The equilibrium dysfunction of the hamsters was evaluated by scoring their behavior according to visual observation and by measuring their time on the rotatory test system. Treatment of animals with sufficient tPA (> or = 0.26 mg/kg) caused a significant amelioration of the behavior and a concomitant significant prolongation of time on the rotating globe. These findings suggest that the equilibrium dysfunction induced by the photochemical reaction was due to the thrombi formed, and that our test system may provide a useful tool for evaluating equilibrium dysfunction in hamsters.

Therapeutic effect of balloon-occluded retrograde transvenous obliteration on portal-systemic encephalopathy in patients with liver cirrhosis

OBJECTIVE

Balloon-occluded retrograde transvenous obliteration (B-RTO) has recently been introduced as a new interventional modality to prevent fatal bleeding from solitary gastric varices. A large portal-systemic shunt including gastric varices also causes severe encephalopathy in some cirrhotic patients. In this study, we evaluated the effect of B-RTO as a candidate therapeutic method to treat chronic recurrent hepatic encephalopathy due mainly to a portal-systemic shunt.

PATIENTS AND METHODS

Since July 1995, we experienced 43 cirrhotic patients with chronic reccurent hepatic encephalopathy. Among them, six patients had anigographically proven large (>1 cm in diameter) portal-systemic shunt, and received B-RTO. B-RTO was carried out only once using 5% ethanolamine oleate with iopamidole to obliterate the portal-systemic shunt for 30 minutes. The median observation period after B-RTO was 29 months (range 23-46 months).

RESULTS

In all 6 patients, encephalopathy had disappeared after B-RTO, and the patients were free of encephalopathy during the following 6 months. B-RTO significantly reduced blood ammonia levels at one month, 3 months, and 6 months later, without affecting serum aspartate aminotransferase activity, total bilirubin and albumin concentrations, and plasma prothrombin time. Encephalopathy relapsed in 4 patients between 6 and 30 months. Additional B-RTO was required and effective in 2 of them.

CONCLUSION

B-RTO is an effective treatment for chronic recurrent hepatic encephalopathy with an angiographically proven portal-systemic shunt.

Mechanism of prostaglandin D(2)-stimulated heat shock protein 27 induction in osteoblasts

We previously showed that prostaglandin D(2) (PGD(2)) stimulates activation of protein kinase C (PKC). We investigated whether PGD(2) stimulates the induction of heat shock protein (HSP) 27 and HSP70 in osteoblast-like MC3T3-E1 cells and the mechanism underlying the induction. PGD(2) increased the levels of HSP27 while having little effect on HSP70 levels. PGD(2) stimulated the accumulation of HSP27 dose dependently in the range between 10 nM and 10 microM. PGD(2) induced an increase in the levels of mRNA for HSP27. The PGD(2)-stimulated accumulation of HSP27 was reduced by staurosporine or calphostin C, inhibitors of PKC. PGD(2) induced the phosphorylation of p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase. The HSP27 accumulation induced by PGD(2) was significantly suppressed by PD98059, an inhibitor of the upstream kinase of p44/p42 MAP kinase, or SB203580, an inhibitor of p38 MAP kinase. Calphostin C suppressed the PGD(2)-induced phosphorylation of p44/p42 MAP kinase and p38 MAP kinase. PD98059 or SB203580 suppressed the PGD(2)-increased levels of mRNA for HSP27. These results strongly suggest that PGD(2) stimulates HSP27 induction through p44/p42 MAP kinase activation and p38 MAP kinase activation in osteoblasts and that PKC acts at a point upstream from both the MAP kinases.

Structure-activity relationships in the deacetylation of O-glucosides of N-hydroxy-N-arylacylamides by mammalian liver microsomes

Structure-activity relationships in the deacylation of O-glucosides of N-hydroxy-N-aryl-acylamides were investigated to provide insights into the metabolic activation of carcinogenic/mutagenic O-glycosides of N-hydroxy-N-arylacylamides. In the subcellular fractions obtained from porcine liver, the deacetylation activity toward O-glucoside of N-hydroxyacetanilide (GAc) was mainly localized in the microsomes. Both the 2-chloro (2ClGAc) and 2-methyl (2MeGAc) derivatives of GAc were not deacetylated by the microsomes. Other compounds having either 3- or 4-substituent (chloro or methyl), however, were deacetylated and showed higher V(max)/K(m) values than that of GAc. 4-Methyl derivative (4MeGAc) was shown to competitively inhibit the deacetylation activity toward GAc, and the K(i) value of 4MeGAc was comparable with its K(m) value obtained in the microsome-catalyzed deacetylation. These apparent K(m) values were shown to correspond to their lipophilicities estimated from retention times on high-performance liquid chromatography (HPLC). As for the effect of acyl groups, the order of V(max)/K(m) values was N-propionyl derivative (GPr)>GAc>N-butyryl derivative (GBu). From the optimized structures and energy levels of the frontier orbitals of these compounds, calculated by the semi-empirical AM1 method, the effects of 2-substituents and acyl groups on the deacetylation activity is thought to be due to a steric factor. From the energy levels of the frontier orbitals of GAc and its 3- or 4-substituted derivatives, the compound having a lower level of LUMO was shown to be deacetylated effectively. There were marked species differences in the microsomal deacetylation activity toward GAc, and the highest activity was found in the rabbit, followed by the porcine, hamster, rat and then bovine liver microsomes.

Involvement of p70 S6 kinase in bone morphogenetic protein signaling: vascular endothelial growth factor synthesis by bone morphogenetic protein-4 in osteoblasts

In the present study, we investigated the effect of bone morphogenetic protein (BMP)-4 on the synthesis of vascular endothelial growth factor (VEGF) in osteoblast-like MC3T3-E1 cells. BMP-4 significantly stimulated VEGF synthesis time-dependently up to 48 h. The stimulatory effect was dose-dependent in the range between 1 and 100 ng/ml. BMP-4 time-dependently phosphorylated p70 S6 kinase. Rapamycin, an inhibitor of p70 S6 kinase, suppressed the BMP-4-stimulated VEGF synthesis as well as the phosphorylation of p70 S6 kinase. The VEGF synthesis by BMP-4 was suppressed by wortmannin and LY294002, inhibitors of phosphatidylinositol 3-kinase. Both wortmannin and LY294002 inhibited the BMP-4-stimulated phosphorylation of p70 S6 kinase. BMP-4 did not affect the phosphorylation of Akt/protein kinase B. Taken together, our results strongly suggest that p70 S6 kinase takes part in BMP-4-stimulated VEGF synthesis as a positive regulator in osteoblasts and that phosphatidylinositol 3-kinase acts at a point upstream from p70 S6 kinase.

Involvement of p70 S6 kinase in bone morphogenetic protein signaling: vascular endothelial growth factor synthesis by bone morphogenetic protein-4 in osteoblasts

In the present study, we investigated the effect of bone morphogenetic protein (BMP)-4 on the synthesis of vascular endothelial growth factor (VEGF) in osteoblast-like MC3T3-E1 cells. BMP-4 significantly stimulated VEGF synthesis time-dependently up to 48 h. The stimulatory effect was dose-dependent in the range between 1 and 100 ng/ml. BMP-4 time-dependently phosphorylated p70 S6 kinase. Rapamycin, an inhibitor of p70 S6 kinase, suppressed the BMP-4-stimulated VEGF synthesis as well as the phosphorylation of p70 S6 kinase. The VEGF synthesis by BMP-4 was suppressed by wortmannin and LY294002, inhibitors of phosphatidylinositol 3-kinase. Both wortmannin and LY294002 inhibited the BMP-4-stimulated phosphorylation of p70 S6 kinase. BMP-4 did not affect the phosphorylation of Akt/protein kinase B. Taken together, our results strongly suggest that p70 S6 kinase takes part in BMP-4-stimulated VEGF synthesis as a positive regulator in osteoblasts and that phosphatidylinositol 3-kinase acts at a point upstream from p70 S6 kinase.

Development of a 1.0 T MR microscope using a Nd-Fe-B permanent magnet

A compact 1.0 T MR microscope was developed using a permanent magnet made of high performance Nd-Fe-B magnetic material and a compact MRI console (54 cm (W) x 77 cm (H) x 60 cm (D), 80 kg weight). Since the magnetic field of the permanent magnet had a large temperature coefficient (-1200 ppm/deg), an internal NMR locking technique was developed for the imaging sequences. The performance of the system was evaluated using several biological specimens. As a result, good SNR 3D images at (50 microm)(3)-(200 microm)(3) voxel dimensions were obtained in practical imaging times (0.5-7.5 hours). Thus we have concluded that the permanent-magnet compact MR microscope has great promise as a research or analytical tool.

P-glycoprotein expression in human major and minor salivary glands

Sodium pump and carbonic anhydrase activity have been described in the salivary glands. However, it remains to be elucidated whether these energy sources are used for secretion, excretion or both. In addition, the differences in the function of excretion and the role of the excretory duct cells are currently unknown in salivary glands. Expression of P-glycoprotein (P-gp), which is an ATPase-binding efflux pump, was tested in normal major and minor salivary glands from humans. P-gp was distributed on the basolateral membrane of serous acinar cells in the major salivary glands and the minor salivary glands. In particular, it was found to be present on the basolateral membrane and cytoplasm of acinar demilunar cells in the anterior lingual gland. Intense expression was identified in the basolateral membrane of the striated duct cells of the major salivary glands. P-gp was distinctly positive in the basolateral and/or luminal membranes of the initial part and in the luminal membrane of the terminal part of the excretory duct cells of the major salivary glands, whereas it was positive in the luminal membranes of both the initial part and the terminal part of the excretory duct cells of the minor salivary glands. These disparate distributions between the major and the minor salivary glands suggest different physiological excretions in the striated duct. P-gp may be physiologically involved in an important part of the transporter system, not only in the acinar serous cells and the striated duct cells, but also in the excretory duct cells in the salivary glands.