Spinal curvature and postural balance in patients with osteoporosis

SUMMARY

Postural deformity might represent another risk factor for postural instability and falls. Relation between spinal curvatures and postural sway were evaluated. Lumbar (not thoracic) kyphosis and spinal inclination have a statistical correlation with postural sway. Postural deformity with lumber kyphosis may represent as a risk factor for falls.

INTRODUCTION

Postural instability has been considered as a risk factor for falls and osteoporotic fractures. Previous studies have demonstrated that several factors display significant relationships with postural instability. Postural deformity might represent another risk factor for postural instability and falls. This study evaluates the influence of spinal curvature on postural instability in patients with osteoporosis.

METHODS

Subjects comprised 93 patients with a mean age of 70 years. Angles of thoracic and lumbar kyphosis and spinal inclination that reflected a forward stooped posture were evaluated using a computer-assisted device. Sway and postural instability were evaluated using a computerized stabilometer showing seven parameters. Relationships among parameters of postural deformity and postural balance were analyzed using Pearson's correlation coefficients.

RESULTS

No significant correlations were observed between any parameters of postural balance and angle of thoracic kyphosis. However, all parameters showed significant positive correlations with angle of lumbar kyphosis (r = 0.251-0.334; p < 0.05-0.001). Moreover, lumbar kyphosis, but not thoracic kyphosis, showed a positive correlation with spinal inclination (r = 0.692, p < 0.001), and all parameters of postural balance showed significant positive correlations with spinal inclination (r = 0.417-0.551, p < 0.001).

CONCLUSION

Lumbar kyphosis, but not thoracic kyphosis, affecting spinal inclination and postural balance may represent a risk factor for falls.

Effect of Double-application of Three Single-step Self-etch Adhesives on Dentin Bonding and Mechanical Properties of Resin-dentin Area

Double-application enhanced the hardness of bonding layer and resin-dentin interface for all the adhesives used; however, it only improved the bond strength to dentin for some of the single-step self-etch adhesives.

Investigation of new cytogenetic biomarkers specific to high-LET radiation usingin vivoandin vitroexposed human lymphocytes

PURPOSE

To find detectable cytogenetic biomarkers that can offer information about the radiation quality of in vivo exposure retrospectively.

MATERIALS AND METHODS

Chromosome-type aberrations of peripheral lymphocytes of uterine cancer patients that received internal gamma- and external X-ray therapy or carbon beam therapy and of victims severely exposed to neutrons and gamma-rays in a criticality accident that occurred in Tokai-mura, Japan were analysed. Data obtained from in vitro irradiation experiments using 60Co gamma-rays and 10 MeV neutrons were compared with the in vivo exposure data.

RESULTS

The ratio of acentric rings to dicentric chromosomes (termed RaD ratio) and that of excess fragments to dicentrics (termed EfD ratio) showed significant (p < 0.05) differences between the two groups of cancer patients, and these ratios for accidental victims were in between the values of the two groups of cancer patients. The in vitro studies using doses equivalent to 1 - 3 Gy of gamma-rays have confirmed that the EfD ratios were increased with the high LET (linear energy transfer) and RaD ratios decreased.

CONCLUSION

The present data show that the RaD and EfD ratios can be used as cytogenetic biomarkers of exposure to high-LET radiation at least within a few years of exposure.

Impact of spinal kyphosis on gastroesophageal reflux disease symptoms in patients with osteoporosis

SUMMARY

Spinal kyphosis has been speculated to participate in the increased frequency of gastroesophageal reflux disease (GERD) in patients with osteoporosis. The present study provides further evidence that increases in lumbar kyphosis and number of vertebral fractures represent very important risk factors for GERD in patients with osteoporosis.

INTRODUCTION

Osteoporosis and spinal kyphosis have been speculated to participate in the increased frequency of gastroesophageal reflux disease (GERD). The present study examined whether GERD in patients with osteoporosis is affected by spinal factors including spinal kyphosis in the presence of oral pharmacotherapies.

METHODS

Subjects comprised 112 patients with osteoporosis (mean age, 78 years) who responded to the Frequency Scale for Symptoms of GERD (FSSG) questionnaire, regardless of complaints. Relationships between total FSSG score and number of vertebral fractures, angles of kyphosis, use of bisphosphonates and nonsteroidal anti-inflammatory drugs (NSAIDs), and total number of oral medicines per day were evaluated. Logistic regression identified factors associated with GERD.

RESULTS

Bisphosphonates and NSAIDs did not affect total FSSG score. Total FSSG score showed significant positive correlations with total number of medicines (r = 0.283, p = 0.0025), angle of lumbar kyphosis (r = 0.576, p = 0.0001), and numbers of thoracic vertebral fractures (r = 0.214, p = 0.0232) and lumbar vertebral fractures (r = 0.471, p < 0.0001). Angle of lumbar kyphosis and number of lumbar vertebral fractures were identified by multivariate analysis as indices affecting the presence of GERD.

CONCLUSION

Increases in angle of lumbar kyphosis and number of lumbar vertebral fractures may represent very important risk factors for GERD in osteoporotic patients.

[Laser therapy for endobronchial malignancies]

Photodynamic therapy (PDT), neodymium yttrium aluminum garnet (Nd-YAG) laser therapy, electrocautery and microwave coagulation therapy are therapeutic options available for management of endobronchial malignancies. All of these treatment modalities have been used for both palliation of late obstructing cancers, and more recently have been used as primary treatment of early stage lung cancers. Only PDT has the curative potential for patients with early superficial squamous cell carcinoma. Nd-YAG laser therapy is used for direct thermal ablation of tissue in endobronchial malignancy. This equipment is the most widely used type of laser for bronchoscopic interventions because it has sufficient power to vaporize tissues and produces an excellent coagulation effect. But the risks of perforation and bleeding are high. Endobronchial electrocautery is the use of high-frequency electrical current that generates heat due to tissue resistance, resulting in destruction of tissue. Argon plasma coagulation (APC) is a form of noncontact electrocoagulation. The risks of perforation and igniting are much lower than with the Nd-YAG laser therapy. Microwave coagulation therapy refers to the use of all electromagnetic methods for inducing tumor destruction by using devices with frequencies of 2450 MHz. It is important to select these treatment methods appropriately according to each case.

Impact of number of resected and involved lymph nodes (LN) at the time of surgical resection on the survival of non-small cell lung cancer (NSCLC)

7514

Background: Total number of lymph-nodes has recently proven prognostic in early breast and colorectal cancer. In this study we retrospectively evaluated the prognostic impact of the number of resected and involved lymph-nodes on the survival of stage I-III NSCLC. Methods: A series of 928 consecutive NSCLC pts who underwent complete lobectomy, bilobectomy or pneumonectomy with lymph-nodes dissection from 1/2000 to 11/2007 at Tokyo Medical University was eligible. Log rank and Cox proportional hazard model was used to estimate survival rates and relative risks. Results: Demographics are as follows: median age: 65.0 (22–87yrs), sex: 547 males and 381 females, median follow-up time: 2.5 yrs, clinical stage: 765 stage I, 84 stage II and 76 stage III, histology: 684 adenocarcinoma, 182 squamous cell carcinoma, and 62 others, operation: 870 lobectomy, 42 bilobectomy and 16 pneumonectomy, mean number of resected LN: 15 (1–49), mean number of involved LN: 0.9 (0–22). We observed a statistically significant increasing trend in overall survival (OS) between 0–3 and 4 and more of number of involved LN (P<0.001). Although a significant increasing in OS of 0–9 of number of resected LN cases compared with 10 and more was observed in all stages (P=0.024), no significant differentiation was observed in clinical stage I cases. Conclusions: This data suggests that there is a significant decrease in OS with 10 and more number of resected LN examined at surgery in NSCLC pts. However, there is no significant different in stage I pts, which implies that selected LN sampling is enough in clinical stage I cases. Further study such as LN dissection vs LN sampling in clinical stage I will be needed.

No significant financial relationships to disclose.

A novel histopathological evaluation method for predicting the outcome of non-small cell lung cancer treated by neoadjuvant therapy

e11574

Background: Chemotherapy, chemoradiotherapy, or radiotherapy is sometimes used to treat non-small cell lung cancer (NSCLC) before surgical resection (neoadjuvant therapy). However, no histopathological evaluation method for predicting the outcome of NSCLC treated by neoadjuvant therapy has been fully assessed. The purpose of this study was to assess a novel histopathological evaluation method for predicting the outcome of NSCLC patients who received neoadjuvant therapy followed by surgical resection. Methods: We reviewed the histopathology of the tumors of 61 NSCLC patients who received neoadjuvant chemotherapy, chemoradiotherapy, or radiotherapy and identified the histological features produced by neoadjuvant therapy by comparing them with the histopathological features of the tumors in 138 NSCLC cases treated by surgery without neoadjuvant therapy. We also measured the area of residual tumor (ART) on the maximum cut surface of the tumors and analyzed the relationships between the histological features, ART, and the outcome. Results: The proportions of cases with the histological features “cholesterin clefts,” “foreign body reactive giant cells,” “stromal hyalinosis,” and “cancer cells more than 50% of which contained a bizarre nucleus” were significantly higher in the neoadjuvant therapy group than in the surgery alone group. However, the presence of none of these features except “stromal hyalinosis” had any significant effect on survival in the neoadjuvant therapy group. Although pathological T factor (ypT) and N factor (ypN) had no significant effect on overall survival, smaller ART (≤400 mm2) and absence of pleural invasion (p(-)) were predictors of a outcome (p=0.004 and p=0.001, respectively). Conclusions: Smaller ART (≤400 mm2) and p(-) predict a better outcome of NSCLC in patients who receive neoadjuvant therapy. We concluded that ART is a novel histopathological parameter for predicting the outcome of NSCLC patients who receive neoadjuvant therapy followed by surgical resection.

No significant financial relationships to disclose.

Treatment-related deaths (TRD) in investigator-initiated cancer cooperative group trials: From the datasets of 44 studies (4,964 patients) by the Japan Clinical Oncology Group (JCOG)

6632

Background: The proportion of Serious Adverse Events (SAE) including TRDs has a critical impact on choosing a new standard therapy as well as the efficacy of treatment in clinical trials. The proportion of TRD (%TRD) has been reported in a single clinical trial, but an overall % TRD in plural clinical trials has merely been evaluated so far. Methods: The JCOG trials which met both of the following criteria were included in this analysis: i) started after 1995 by 2008, ii) primary analysis was completed. In JCOG, attribution of all reported SAE are classified by Data and Safety Monitoring Committee into 5 categories (definite, probable, possible, unlikely, not related) according to causality to protocol treatment, and the death with causality judged as definite, probable, or possible is defined as TRD. The total number of any deaths and TRD were counted in all included trials and the incidences (%) of TRD were calculated. The association between %TRD and the following trial profiles was evaluated: arm (standard vs. testing), phase, modality and median survival time of each arm. Results: In total, 44 JCOG trials (67 arms) with 4,964 patients were included in the analysis. The number of all deaths and TRD were 2,974 and 60. Thus, the overall %TRD for all enrolled patients was 1.2% (95%CI, 0.9–1.6%), and %TRD among all deaths was 2.0% (95%CI, 1.5–2.6%). Major results of the association between %TRD and trial profiles are shown in the table. The later phase trials showed the lower %TRD, and the trials with shorter MST tended to have higher %TRD. Conclusions: When the trial is in earlier phase and includes more advanced disease, the trial should be planned and performed more carefully about minimization of patient risk.

[Table: see text]

No significant financial relationships to disclose.

Predictive factors of outcome and clinical management of adjuvant S-1 chemotherapy for gastric cancer

e15676

Background: Adjuvant S-1 chemotherapy has become a standard treatment for stage II and III gastric cancer, following the Adjuvant Chemotherapy Trial of TS-1 for Gastric Cancer (ACTS-GC). This study was designed to identify factors that can be used for predicting the outcome and clinical management of adjuvant S-1 chemotherapy in patients with stage II and III gastric cancer. Methods: We retrospectively examined 97 consecutive patients with stage II or III gastric cancer who received S-1 chemotherapy after gastrectomy to investigate factors associated with outcome and clinical management. S-1 (80 mg/m2/day) was orally administered twice daily for 28 consecutive days, followed by a 14-day rest period. As a rule, this protocol was continued for one year after gastrectomy. According to toxicity profiles, dose reduction or dose schedule modification was performed. Results: Patients consisted of 63 males and 34 females (median age, 59 years; range, 35–80 years), and those undergoing total gastrectomy/subtotal gastrectomy = 40/57. The median follow-up period after gastrectomy was 43.0 months (range, 5.3–73.4 months). As for adjuvant S-1 chemotherapy, dose reduction and dose schedule modification were conducted in 59% and 40% of the patients, respectively. Of the patients needing dose reduction, 79% underwent reduction within three months of treatment. The most common reason for dose reduction during the treatment period was anorexia (47%), followed by diarrhea (32%), leukopenia (24%) and rash (16%) with overlapping reasons. The duration period of the treatment was at least 3 months in 88%, at least 6 months in 82%, and scheduled 12 months in 73%. Twenty six patients discontinued treatment due to adverse event (20 patients), recurrent disease (2 patients) and other reasons (4 patients). The median duration until treatment discontinuation was 4.0 months. To date, 15 patients have recurrent disease. Significant predictive factors for recurrence were not statistically identified. Conclusions: Most patients (73%) could complete the scheduled treatment duration by dose reduction and dose schedule modification.

No significant financial relationships to disclose.

Alteration of Adults' Subjective Feeling of Familiarity toward Infants' Sounds

Many adults may have lower subjective feelings of familiarity toward infants' vocalizations since infants' sounds are different from those of adults. However, mothers frequently exposed to infants' vocalizations may be more familiar and less averse. To test this hypothesis, 21 mothers ( M age = 31.1 yr., SD = 4.3) of infants ( M age = 8.2 mo., SD = 3.5), 18 mothers ( M age = 34.4 yr., SD = 4.8) of children between two and five years of age ( M age = 2.8 yr., SD = 1.0), and 17 women ( M age = 29.2 yr., SD = 11.1) with no children were exposed to 20 types of sounds. Of these sounds, 14 were produced by infants. Although the mothers of infants did not recognize sounds as those of an infant's vocalization, they showed higher subjective feelings of familiarity toward the timbres of the vowel-like stimuli than did the other groups. By contrast, the subjective feelings of familiarity for nonspeech sounds did not differ among groups. Maternal experiences may change women's recognition of perceived sounds.

Chemosensitivity of patients with recurrent esophageal cancer receiving perioperative chemotherapy

Perioperative chemotherapy (CT) and chemoradiotherapy are widely used for advanced esophageal cancer. We evaluated the chemosensitivity of patients displaying recurrent esophageal cancer after esophagectomy with perioperative CT. From the database at National Cancer Center Hospital in Tokyo, we extracted recurrent esophageal cancer cases after perioperative CT and evaluated the effectiveness of the first CT against the recurrent disease according to the duration between termination of the original perioperative CT and recurrence with treatment-free intervals (TFIs) <or=6 and >6 months. Systemic CT for their recurrent disease was performed for 30 esophageal cancer patients after perioperative CT. All patients received 5-fluorouracil and cisplatin as perioperative CT, with relapses occurring at TFIs <or=6 months in 11 patients (eight received platinum-containing regimens and three received docetaxel for their recurrent disease) and >6 months in 19 patients (all received platinum-containing regimens). The response rate of patients experiencing a recurrence at TFIs <or=6 and >6 months was 0 and 37% (P = 0.029), the median progression-free survival was 2.8 and 4.8 months (log-rank P = 0.001) and the median overall survival was 6.1 and 10.2 months (log-rank P = 0.012), respectively. Recurrence at the TFI <or=6 months could represent resistance to CT, so regimens may need to be altered depending on a patient's specific TFI.

Phase I/II study of oxaliplatin with oral S-1 as first-line therapy for patients with metastatic colorectal cancer

Two phase II studies of S-1 monotherapy have shown promising response rates (RR) of 35–40% with good tolerability in patients with untreated metastatic colorectal cancer. To investigate the usefulness of S-1 plus oxaliplatin (SOX) as an alternative to infusional 5-fluorouracil/leucovorin plus oxaliplatin, the recommended dose (RD) of SOX was determined, and its safety and preliminary efficacy were evaluated in a phase I/II study. Oxaliplatin was administered at a dose of 100 mg m⁻² (level 1) or 130 mg m⁻² (level 2) on day 1, and S-1 (80–120) was given twice daily for 2 weeks followed by a 1-week rest. This schedule was repeated every 3 weeks. Level 2 was determined to be the RD. For the 28 patients who received the RD, the median treatment course was 6.5 cycles (2–14), RR of 50% (1 CR and 13 PR: 95% CI 31–69%), with a median progression-free survival of 196 days. Survival rate (1 year) was 79%. Peripheral neuropathy was observed in all patients but with no functional disorders. Major grade 3 or 4 adverse reactions at the RD were neutropaenia (14%), thrombocytopaenia (28%), and diarrhoea (3%). SOX regimen is effective and easily manageable without central vein access.

Impacts of excision repair cross-complementing gene 1 (ERCC1), dihydropyrimidine dehydrogenase, and epidermal growth factor receptor on the outcomes of patients with advanced gastric cancer

Using laser-captured microdissection and a real-time RT-PCR assay, we quantitatively evaluated mRNA levels of the following biomarkers in paraffin-embedded gastric cancer (GC) specimens obtained by surgical resection or biopsy: excision repair cross-complementing gene 1 (ERCC1), dihydropyrimidine dehydrogenase (DPD), methylenetetrahydrofolate reductase (MTHFR), epidermal growth factor receptor (EGFR), and five other biomarkers related to anticancer drug sensitivity. The study group comprised 140 patients who received first-line chemotherapy for advanced GC. All cancer specimens were obtained before chemotherapy. In patients who received first-line S-1 monotherapy (69 patients), low MTHFR expression correlated with a higher response rate (low: 44.9% vs high: 6.3%; P=0.006). In patients given first-line cisplatin-based regimens (combined with S-1 or irinotecan) (43 patients), low ERCC1 correlated with a higher response rate (low: 55.6% vs high: 18.8%; P=0.008). Multivariate survival analysis of all patients demonstrated that high ERCC1 (hazard ratio (HR): 2.38 (95% CI: 1.55-3.67)), high DPD (HR: 2.04 (1.37-3.02)), low EGFR (HR: 0.34 (0.20-0.56)), and an elevated serum alkaline phosphatase level (HR: 1.00 (1.001-1.002)) were significant predictors of poor survival. Our results suggest that these biomarkers are useful predictors of clinical outcomes in patients with advanced GC.

Back extensor strength and lumbar spinal mobility are predictors of quality of life in patients with postmenopausal osteoporosis

To assess the effect of multiple factors on quality of life (QOL) in osteoporosis, relationships between the QOL and possible spinal factors were analyzed in 174 postmenopausal women with osteoporosis. Back extensor strength and lumbar spinal mobility were the most important factors for QOL in these patients.

INTRODUCTION

Quality of life (QOL) in patients with osteoporosis and vertebral fractures is impaired by the decline of total spinal mobility, although it is not clear to what extent. This study aimed to assess the effect of multiple factors on QOL in patients with osteoporosis.

METHODS

QOL of 174 postmenopausal women with osteoporosis (mean, 68 years old) was evaluated using the Japanese Osteoporosis QOL Questionnaire (JOQOL). Correlations between the JOQOL score, bone mineral density (BMD) of the lumbar spine/proximal femur/whole body, the kyphosis angle and mobility of thoracic and lumbar spine, the number of vertebral fractures, grip strengths of dominant and non-dominant hands, and isometric back extensor strength (BES) were analyzed.

RESULTS

JOQOL showed significant correlation (p < 0.05) with age (r = -0.303), BES (r = 0.455), dominant and non-dominant grip strengths (r = 0.273 and r = 0.255, respectively), number of vertebral fractures (r = -0.282), BMDs of proximal femur and whole body (r = 0.200 and r = 0.157, respectively), lumbar kyphosis angle (r = -0.296), and lumbar spinal mobility (r = 0.345). Multiple regression analysis revealed that the BES and lumbar spinal mobility were the significant contributors to the JOQOL (p < 0.05).

CONCLUSION

BES and lumbar spinal mobility are the important factors for QOL in patients with postmenopausal osteoporosis.

Effect of low-intensity back exercise on quality of life and back extensor strength in patients with osteoporosis: a randomized controlled trial

Randomized controlled study in 80 postmenopausal women with osteoporosis was conducted to investigate the effect of a home-based, simple, low-intensity exercise. Low-intensity back-strengthening exercise was effective in improving the quality of life and back extensor strength.

INTRODUCTION AND HYPOTHESIS

Back-strengthening exercise is effective in increasing back extensor strength and decreasing risk of vertebral fractures. We hypothesized that a home-based, simple, low-intensity exercise could enhance back extensor strength and improve the quality of life and/or spinal range of motion in postmenopausal women in a short-term follow-up.

METHODS

Eighty postmenopausal women with osteoporosis were randomly assigned to a control group (n = 38) or an exercise group (n = 42). Subjects were instructed to lift their upper trunk from a prone position antigravity and maintain the neutral position. Isometric back extensor strength, spinal range of motion, and scores for quality of life were evaluated at baseline and 4 months.

RESULTS

Back extensor strength significantly increased both in the exercise group (26%) and in the control group (11%). Scores for quality of life increased in the exercise group (7%), whereas it remained unchanged in the control group (0%). There was a significant difference in quality of life score between the groups (p = 0.012).

CONCLUSIONS

Low-intensity back-strengthening exercise was effective in improving the quality of life and back extensor strength in patients with osteoporosis.

Effect of dentin depth on hybridization quality using different bonding tactics in vivo

OBJECTIVES

Incomplete resin infiltration and polymerization of adhesive contributed to nanoleakage formation. This study tested the null hypothesis that adoption of different bonding tactics and dentine depth will not affect hybridization quality in vivo.

METHODS

Class V cavities were prepared on the labial/buccal surface of monkey teeth. They were bonded by Single Bond (a two-step total-etch adhesive), Clearfil SE Bond (a two-step self-etch adhesive), or Clearfil S(3) Bond (an all-in-one self-etch adhesive). Combined nanoleakage analysis and quantitative immunolabeling evaluation were carried out in the hybrid layer formed in both cervical superficial and deep dentine.

RESULTS

Single Bond showed reticular and spotted nanoleakage while Clearfil SE Bond and Clearfil S(3) Bond presented only a spotted one. While Single Bond showed increased concentration of labeling of type I collagen within the deep part of the hybrid layer, two self-etch adhesives-Clearfil SE Bond and Clearfil S(3) Bond revealed a homogeneous labeling pattern, even if the latter presented a significantly increased labeling index in deep dentine.

CONCLUSIONS

Different bonding tactics showed different nanoleakage patterns and immunolabeling index, and was influenced by dentine depth at different levels in vivo.

Direct measurement of density oscillation induced by a radio-frequency wave

An O-mode reflectometer at a frequency of 25.85 GHz was applied to plasmas heated by the high harmonic fast wave (21 MHz) in the TST-2 spherical tokamak. An oscillation in the phase of the reflected microwave in the rf range was observed directly for the first time. In TST-2, the rf (250 kW) induced density oscillation depends mainly on the poloidal rf electric field, which is estimated to be about 0.2 kV/m rms by the reflectometer measurement. Sideband peaks separated in frequency by ion cyclotron harmonics from 21 MHz, and peaks at ion cyclotron harmonics which are suggested to be quasimodes generated by parametric decay, were detected.

A phase I and pharmacokinetic study of NK105, a paclitaxel-incorporating micellar nanoparticle formulation

This phase I study was designed to examine the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs), the recommended dose (RD) for phase II, and the pharmacokinetics of NK105, a new polymeric micelle carrier system for paclitaxel (PTX). NK105 was administered as a 1-h intravenous infusion every 3 weeks, without antiallergic premedication. The starting dose was 10 mg m⁻², and the dose was escalated according to the accelerated titration method. Nineteen patients were recruited. The tumour types treated included pancreatic (n=11), bile duct (n=5), gastric (n=2), and colonic (n=1) cancers. Neutropenia was the most common haematological toxicity. A grade 3 fever developed in one patient given 180 mg m⁻². No other grades 3 or 4 nonhaematological toxicities, including neuropathy, was observed during the entire study period. DLTs occurred in two patients given 180 mg m⁻² (grade 4 neutropenia lasting for more than 5 days). Thus, this dose was designated as the MTD. Grade 2 hypersensitivity reactions developed in only one patient given 180 mg m⁻². A partial response was observed in one patient with pancreatic cancer. The maximum concentration (C_max) and area under the concentration (AUC) of NK105 were dose dependent. The plasma AUC of NK105 at 150 mg m⁻² was approximately 15-fold higher than that of the conventional PTX formulation. NK105 was well tolerated, and the RD for the phase II study was determined to be 150 mg m⁻² every 3 weeks. The results of this phase I study warrant further clinical evaluation.

Relationship of insulin-like growth factor-1 receptor and epidermal growth factor receptor expression to clinical outcomes in patients with colorectal cancer

4117

Background: Insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR), and HER2 have been reported to regulate tumor growth by interfering with apoptosis, cell proliferation, angiogenesis, and metastasis. However, the clinical significance of these molecules in colorectal cancer (CRC) remains undetermined. To gain further insight, we evaluated the prognostic implications of these biomarkers in patients with CRC treated with fluoropyrimidines or irinotecan. Methods: The study group comprised 91 patients who underwent surgery at National Cancer Center Hospital and subsequently received fluoropyrimidines as 1st-line chemotherapy for recurrent or residual tumors. The expressions of IGF-1R, EGFR, and HER2 in surgically removed specimens of primary lesions were analyzed immunohistochemically to determine the prognostic significance of these biomarkers. Results: IGF-1R expression (defined as >10% membranous staining) was found in 81 tumors (89%), EGFR in 77 (85%), and HER2 in 3 (3%). IGF-1R expression significantly correlated with EGFR expression (P=0.038). Overexpression (defined as >50% membranous staining) of IGF-1R was found in 48 tumors (53%), EGFR in 57 (63%), and HER2 in 2 (2%). Overexpression of IGF-1R significantly correlated with shorter survival from the start of 1st-line chemotherapy (P=0.032). Overexpression of EGFR was a significant predictive factor for a clinical response to fluoropyrimidines (P=0.037) and tended to correlate with TTP in patients given irinotecan as 2nd-line therapy (P=0.087). A multivariate analysis of potential prognostic factors showed that IGF-1R expression and worse performance status were independent predictors of poor outcomes ( Table ). Conclusions: IGF-1R and EGFR were highly positive in patients with CRC. Overexpression of IGF-1R predicts a poor outcome, and overexpression of EGFR predicts a good clinical response to fluoropyrimidines.

[Table: see text]

No significant financial relationships to disclose.

Impact of insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR), and HER2 expressions on outcomes of patients with gastric cancer

4539

Background: Insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR), and HER2 expressions have been reported to correlate with clinical outcomes in several solid tumors. However, the clinical significance of these biomarkers in gastric cancer (GC) remains unclear. Detailed exploratory evaluations are required to better understand their clinical implications. Methods: The study group comprised 87 patients who underwent gastrectomy at National Cancer Center Hospital and subsequently received chemotherapy for recurrent or residual tumor. Using immunohistochemical techniques, we analyzed the expressions of IGF-1R, EGFR, and HER2 in surgically removed tumor specimens to determine the prognostic significance of these biomarkers. Results: IGF-1R expression (defined as >10% membranous staining) was found in 67 tumors (77%), EGFR in 55 tumors (63%), and HER2 in 16 tumors (18%). IGF-1R expression correlated with EGFR expression (P=0.019) as well as with HER2 expression (P=0.001). A univariate analysis revealed that IGF-1R expression correlated with shorter survival (P=0.030). A multivariate analysis of potential prognostic factors showed that IGF-1R expression, worse performance status and pathological stage, and diffuse type tumor were independent predictors of poor outcomes ( Table ). Conclusions: IGF-1R expression in surgical GC specimens may be a predictor of poor outcomes in postoperative patients with GC. Our data suggest that anti-IGF-1R strategies may prove valuable in such patients.

[Table: see text]

No significant financial relationships to disclose.

Association of a novel polymorphism G-133C of thymidylate synthase (TYMS) gene with 5-FU-related severe diarrhea in Japanese patients with colorectal cancer

14108

Background: 5-FU remains a key drug for the treatment of several cancers, including cancers of the colorectum, stomach, and breast. Increasing evidence suggests that genetic polymorphism results in increased toxicity. This prospective study intended to elucidate the relations between 5-FU-related toxicity and polymorphisms of several genes. Methods: Blood for genotyping was obtained before treatment. Blood samples were drawn at 2-week intervals for 8 weeks to assess hematologic toxicity. Adverse events were assessed according to NCI CTC, v2.0. The genes encoding TYMS and thymidine phosphorylase (ECGF1) were analyzed with leukocyte DNA obtained from patients with colorectal cancer who received 5-FU (500 or 600 mg/m2) and leucovorin (LV) (250 mg/m2) weekly for 6 weeks every 8 weeks. Results: Seventy-eight patients with colorectal cancer were enrolled and genotyped. Toxicity was evaluated in all patients. No genetic polymorphisms detected were significantly associated with 5-FU-related hematological toxicity. Only G- 133C located in the 5’-UTR region of the TYMS gene was significantly associated with 5-FU-related grade 3 diarrhea. Conclusions: The TYMS G-133C SNP may be a critical determinant of severe diarrhea in patients treated with 5-FU/LV. [Table: see text]

No significant financial relationships to disclose.

Effect of alpha-helical CRH on quantitative electroencephalogram in patients with irritable bowel syndrome

Patients with irritable bowel syndrome (IBS) may have a higher tone of corticotropin-releasing hormone (CRH) in the brain. We tested our hypothesis that peripheral administration of CRH antagonist, alpha-helical CRH(9-41) (alphahCRH), improves decreased alpha power spectra and increased beta power spectra of electroencephalogram (EEG) in IBS patients. A barostat bag was inserted to the descending colon of 10 normal controls and 10 IBS patients. The EEG power spectra and topography were measured during baseline period and colonic distention period with the administration of saline followed by the administration of 10 microg kg(-1) of alphahCRH. IBS patients showed a significantly lower alpha power percentage and a higher beta power percentage than normal controls during baseline. Colonic distention induced a decrease in the alpha power percentage and an increase in the beta power percentage in both groups without difference between groups. After the administration of alphahCRH, changes in the EEG power spectra in response to colonic distention were blunted and the differences in the EEG power spectra between IBS patients and controls vanished. Peripheral administration of alphahCRH almost normalized EEG activities in IBS patients. Our data strongly suggest that CRH plays an important role in IBS.

Frequent methylation-associated silencing of a candidate tumor-suppressor, CRABP1, in esophageal squamous-cell carcinoma

Epigenetic alterations and the resulting inactivation of tumor suppressor genes often contribute to the development of various cancers. To identify novel candidates that may be silenced by aberrant methylation in esophageal squamous-cell carcinoma (ESCC), we analysed ESCC cell lines by a recently developed method known as bacterial artificial chromosome array-based methylated CpG island amplification (BAMCA), and selected candidates through BAMCA-assisted strategy. In the course of this program, we identified frequent CpG methylation-dependent silencing of the gene encoding cellular retinoic acid binding protein 1 (CRABP1) in our panel of ESCC cell lines. Expression of CRABP1 mRNA was restored in gene-silenced ESCC cells after treatment with 5-aza 2'-deoxycytidine. The DNA methylation status of the CRABP1 CpG island with clear promoter activity correlated inversely with expression of this gene. CpG methylation of CRABP1 was frequently observed in primary ESCC tissues as well. Restoration of CRABP1 expression in ESCC cells lacking the protein reduced cell growth by inducing arrest at G(0)-G(1), whereas knockdown of the gene in cells expressing CRABP1 promoted cell growth. Among 113 primary ESCC tumors, the absence of immunoreactive CRABP1 was significantly associated with de-differentiation of cancer cells and with distant lymph-node metastases in the patients. These results indicate that CRABP1 appears to have a tumor-suppressor function in esophageal epithelium, and its epigenetic silencing may play a pivotal role during esophageal carcinogenesis. Its expression status in biopsies or resected tumors might serve as an index for identifying ESCC patients for whom combined therapeutic modalities would be recommended.

Induction of prostaglandin E synthase by gastroesophageal reflux contents in normal esophageal epithelial cells and esophageal cancer cells

The synthesis of prostaglandin E2 (PGE2) requires cyclooxygenase (COX) and prostaglandin E synthase (PGES). There are two forms of PGES: cytosolic PGES (cPGES) and microsomal PGES (mPGES)-1. In this study, we investigated the effects of gastroesophageal reflux (GER) contents on PGES and COX-2 in esophageal cells. We incubated a human normal esophageal cell line, two esophageal squamous cell carcinoma (SCC) cell lines, and two esophageal adenocarcinoma (ADC) cell lines with GER contents. The production of PGE2 by these cells was assayed with an enzyme immunoassay kit. The protein expression of COX-2, cPGES, and mPGES-1 was confirmed by immunoblot analysis. The following results were obtained: GER contents induced the expression of COX-2 in all five cell lines. In normal esophageal cells, cPGES, but not mPGES-1, was detected in the cytosolic fraction. GER contents induced the expression of cPGES in the microsomal fraction. In SCC cells, cPGES was expressed in the cytosolic fraction, and mPGES-1 was expressed in the microsomal fraction. GER contents induced the expression of mPGES-1 in the microsomal fraction. In ADC cells, cPGES was expressed in both the cytosolic and microsomal fractions. GER contents induced the expression of both cPGES and mPGES-1 in the microsomal fraction. In conclusion, our results suggest that GER contents induce PGE2 production in esophageal cells. However, there are different isoforms of PGES in normal cells, SCC cells, and ADC cells.

Interleukin-8 production via protease-activated receptor 2 in human esophageal epithelial cells

Interaction between proteases and protease-activated receptor (PAR) 2 has been proposed to mediate inflammatory and immune response in the gastrointestinal tract. Recently, increase in interleukin (IL)-8 in the esophageal mucosa has been associated with the pathogenesis of esophagitis induced by reflux of gastric acids, bile acids or trypsin. The aims of the present study were to determine PAR2 expression in normal human esophageal epithelial cells (HEEC) and to evaluate the mediation of IL-8 production by trypsin-PAR2 interaction in HEEC. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis revealed that PAR2 mRNA and protein were constitutively expressed in HEEC without upregulation by the stimulation with tumor necrosis factor alpha or trypsin. IL-8 was produced in a dose-dependent fashion when cells were stimulated with a PAR2 agonist such as trypsin or SLIGKV-amide. Blocking antibody to PAR2, camostat mesilate (a trypsin inhibitor), p-38 mitogen-activated protein kinase (MAPK) inhibitors or ERK1/2 inhibitors reduced IL-8 production from trypsin-stimulated HEEC. Mutation of the NFkappaB-, AP-1- and NF-IL-6-binding site on the IL-8 gene promoter abrogated the induction of luciferase activities stimulated with trypsin by 100, 80 and 50%, respectively. These results indicate that PAR2 activation in HEEC by trypsin induces NFkappaB- and AP-1-dependent IL-8 production in association with activation of p38 MAPK and ERK1/2, suggesting that esophageal inflammation may be induced by PAR2 activation via reflux of trypsin.

Inhibitory effect of cinnamaldehyde, derived from Cinnamomi cortex, on the growth of influenza A/PR/8 virus in vitro and in vivo

We have investigated the inhibitory effect of trans-cinnamaldehyde (CA), one of the principal constituents of essential oil derived from Cinnamomi cortex, on the growth of influenza A/PR/8 virus in vitro and in vivo. When 1-h drug treatment was initiated at various times post-infection (p.i.) in Madin-Darby canine kidney cells using a fixed dose of CA (40 microM), the maximum inhibitory effect (29.7% virus yield of control) was obtained when drug treatment was started at 3h p.i. Under the same treatment schedule, CA inhibited the virus growth in a dose-dependent manner (20-200 microM), and, at 200 microM, the virus yield was reduced to an undetectable level. RT-PCR and SDS-PAGE analyses showed that CA inhibited viral protein synthesis at the post-transcriptional level. In mice infected with the lung-adapted PR-8 virus, inhalation (50mg/cage/day) and nasal inoculation (250 microg/mouse/day) of CA significantly increased survival rates on the 8 days to 100% and 70%, respectively, in contrast to a survival rate of 20% in the untreated control group. Importantly, inhalation of CA caused virus yield reduction by 1 log in bronchoalveolar lavage fluid on day 6 after infection, compared with that of the untreated control group. These findings might provide further support to the empirical indication of Cinnamomi cortex-containing Kampo medicines for acute respiratory infectious diseases.

Ikaros is a mutational target for lymphomagenesis in Mlh1-deficient mice

Deficiencies in DNA mismatch repair (MMR) result in replication errors within key tumor suppressor genes or oncogenes, and cause hereditary nonpolyposis colorectal cancer (HNPCC). Hematological malignancy with microsatellite instability is also associated with defective MMR, but little is known about the target genes for MMR. Here we identified Ikaros, a master transcription factor of lymphoid lineage commitment and differentiation, as a mutational target in spontaneous and radiation-induced T-cell lymphomas in Mlh1-deficient mice. Three quarters of lymphomas lacked Ikaros protein expression, which resulted from a frameshift mutation that created a stop codon. Mononucleotide repeat sequences at 1029-1034(C)6 and 1567-1572(G)6 in Ikaros were mutational hot spots with a one-base deletion occurring with a frequency of 45 and 50%, respectively. Point mutations and splicing alterations were also observed. In total, 85% of the lymphomas showed aberrations in Ikaros. The characteristic of Mlh1-deficient lymphomas is harboring of multiple mutations simultaneously in the same tumor, displaying a combination of two frameshift mutations at different repeats, frameshift and point mutations, and/or deletion mutations. This is the first report of Ikaros mutations coupled with Mlh1 deficiency in lymphomagenesis.

Genetic variations and haplotype structures of the ABCB1 gene in a Japanese population: an expanded haplotype block covering the distal promoter region, and associated ethnic differences

As functional ABCB1 haplotypes were recently reported in the promoter region of the gene, we resequenced the ABCB1 distal promoter region, along with other regions (the enhancer and proximal promoter regions, and all 28 exons), in a total of 533 Japanese subjects. Linkage disequilibrium (LD) analysis based on 92 genetic variations revealed 4 LD blocks with the same make up as previously described (Blocks -1, 1, 2 and 3), except that Block 1 was expanded to include the distal promoter region, and that a new linkage between polymorphisms -1,789G>A in the distal promoter region and IVS5 + 123A>G in intron 5 was identified. We re-assigned Block 1 haplotypes, and added novel haplotypes to the other 3 blocks. The reported promoter haplotypes were further classified into several types according to tagging variations within Block 1 coding or intronic regions. Our current data reconfirm the haplotype profiles of the other three blocks, add more detailed information on functionally-important haplotypes in Block 1 and 2 in the Japanese population, and identified differences in haplotype profiles between ethnic groups. Our updated analysis of ABCB1 haplotype blocks will assist pharmacogenetic and disease-association studies carried out using Asian subjects.

Significance of nerve growth factor overexpression and its autocrine loop in oesophageal squamous cell carcinoma

Nerve growth factor (NGF) is overexpressed not only in nervous system, but also in several types of cancers. However, the role of NGF in oesophageal squamous cell carcinoma (OESCC) remains unclear. Here, we show the first evidence of NGF-TrkA autocrine loop and clinical significance of NGF overexpression in OESCC. Immunohistochemical study of 109 OESCC specimens revealed that NGF overexpression, found in 63 out of 109 patients (57.8%), was associated with lymph node metastasis, distant metastasis, higher TNM stage, poorer tumour differentiation, and poorer survival. NGF overexpression was also associated with strong expression of TrkA and negative expression of low-affinity neurotrophin receptor (p75NTR). Semiquantitative reverse transcription–polymerase chain reaction (RT–PCR) of 19 surgical specimens showed upregulation of NGF mRNA in 17 out of 19 (89%) patients. All five OESCC cell lines tested in vitro secreted detectable NGF in enzyme-linked immunosorbent assay, and expressed TrkA and p75NTR on RT–PCR and Western blot. The motility of HSA/c, one of the OESCC cell lines overexpressing NGF, was significantly decreased by either neutralising anti-NGF antibody, an inhibitor of TrkA, or NGF-small interfering RNA in transwell migration assay. Our findings suggest that NGF is of potential interest not only as a prognostic factor, but also as a novel therapeutic target in OESCC.

Phase I study of NK105, a paclitaxel-incorporating micellar nanoparticle, in patients with advanced cancer

2018

Background: NK105 is a new polymeric micelle carrier system for paclitaxel (PTX). A preclinical study revealed that the plasma AUC and tumor AUC of NK105 were 90-fold higher and 25-fold higher, respectively, than those of free-PTX, i.e., the conventional PTX formulation. NK105 had higher in vivo antitumor activity and lower neurotoxicity than free-PTX. This phase I study was designed to examine the MTD, DLTs, recommended dose (RD) for phase II, and the pharmacokinetics of NK105. Methods: NK105 was administered as a 1-hour intravenous infusion every 3 weeks, without antiallergic premedication. The starting dose was 10 mg PTX equivalent/m2, and the dose was escalated according to the accelerated titration method. Results: To date, 17 patients (pts) have received the following doses: 10 mg/m2 (n=1); 20 mg/m2 (n=1); 40 mg/m2 (n=1); 80 mg/m2 (n=1); 110 mg/m2 (n=3); 150 mg/m2 (n=5); and 180 mg/m2 (n=5). The tumor types treated included pancreatic (n=9), bile duct (n=5), gastric (n=2), and colonic (n=1) cancers. Neutropenia was the most common hematological toxicity. Grade 3 fever developed in 1 pt given 180 mg/m2. No other grade 3 or 4 non-hematological toxicity, including neuropathy, was observed. DLTs occurred in pts given 180 mg/m2 (grade 4 neutropenia lasting for more than 5 days). This dose was designated as the MTD. Allergic reactions developed in only one pt at 180 mg/m2, who was sensitive to other drugs such as antibiotics anti-inflammatory. A partial response was observed in one pt with pancreatic cancer and pts with colonic and gastric cancer had stable disease. The Cmax and AUC of NK105 were dose dependent. The plasma AUC of NK105 at 180 mg/m2 was approximately 30-fold higher than that of the conventional formulation of PTX. Conclusions: Accrual is ongoing at the 150 mg/m2 dose level to determine the RD. DLT was Grade 4 neutropenia. NK105 produces prolonged high levels of PTX in plasma. A 1-hour infusion of NK105 every 3 weeks was feasible, well tolerated, and effective in patients with pancreatic cancer. Even after the long term usage, only grade 1 or 2 neuropathy was observed. NK105 will be evaluated in Phase II studies of patients with advanced pancreatic and gastric cancers.

No significant financial relationships to disclose.

Phase II study of S-1 plus irinotecan (SIR) in patients with advanced colorectal cancer

13508

Background: Infusional fluorouracil and leucovorin (5-FU/LV) plus irinotecan is one of the standard regimens for the treatment of metastatic colorectal cancer (MCRC). S-1, a combination of tegafur, 5-chloro-2,4-dihydroxypyridine, and oxonic acid, is an oral DPD inhibitory fluoropyrimidine shown to be very effective as first-line treatment for MCRC. The response rate with S-1 was 35–40% in patients with chemo-naïve MCRC. This study evaluated the efficacy and toxicity of S-1 plus irinotecan (SIR). Methods: Eligible patients had untreated MCRC as confirmed histologically, PS 0–1, adequate organ function, and provided written informed consent. First-line SIR was given in 3-week treatment cycles: intravenous irinotecan 150 mg/m2 (day 1) and oral S-1 40 mg/m2 twice daily for 14 days followed by 7 days of rest. Results: Forty-one patients were enrolled; 40 fulfilled all eligibility criteria, and 1 had double cancers. There were 28 men; median age 60 years (range, 23–74); ECOG PS 0/1, 35/6. The overall response rate was 63% (95%CI, 48–78%). Five patients had a CR, 20 a PR, 11 SD, and 2 PD. Median TTP was 8.0 months (range, 1.4–13.8 months); MST was not reached. The most frequent grade 3/4 toxicities included: neutropenia (17%), diarrhea (15%), and anorexia (12%). One patient had Grade 4 constipation. The relative dose intensity of irinotecan was 84%, and that of S-1 was 79%. Dose reduction of irinotecan was required in 41 of 327 administered cycles, and that of S-1 was required in 15 of 327. Conclusions: SIR is a highly active and convenient first-line therapy for MCRC, with an acceptable toxicity profile. S-1 has the potential to replace infusional 5-FU/LV plus irinotecan for MCRC.

No significant financial relationships to disclose.

Impact of dihydrofolate reductase (DHFR) and thymidylate synthase (TS) on outcomes of postoperative patients with gastric cancer

4053

Background: The clinical significance of biomarkers in resected gastric cancer (GC) remains unclear. Detailed exploratory evaluations are required to better understand the clinical implications of biomarkers. Methods: The study group comprised 87 patients who received chemotherapy for recurrent or residual GC after resection of their primary tumors at National Cancer Center Hospital. The patients received 1 to 5 regimens of chemotherapy (median: 2). Total RNA was isolated from laser-captured tumor cells of the resected cancer specimens, and the gene expressions of TS, DPD, DHFR, ERCC1, MRP1, and 22 other biomarkers related to anticancer drug sensitivity were quantitatively evaluated by a real-time RT-PCR assay. Results: The gene expressions of TS, DHFR, MTHFD, RRM1, and ERCC1 were significantly related to survival ( Table ). Multivariate analysis revealed that high DHFR (p < 0.001, RR = 1.70 [95% CI, 1.28–2.29]) and high TS (p = 0.004, RR = 1.53 [1.15–2.06]) gene expressions were independently related to poor survival. As compared with intestinal type tumors, diffuse type tumors had higher DPD (p < 0.001) and lower Her2 (p < 0.001) gene expressions. As for first line chemotherapy, an analysis of 29 patients treated with S-1, an oral DPD inhibitory fluoropyrimidine, showed that patients with diffuse type tumors tended to respond better (p = 0.13) than those with intestinal type tumors. An analysis of 29 patients treated with cisplatin plus irinotecan as first line therapy showed that low ERCC1 gene expression was slightly but not significantly related to a better response (p = 0.087). Analyses of patients treated with other first line regimens revealed no significant correlation of any biomarker with response. Conclusions: Increased gene expressions of DHFR and TS in surgical specimens are significantly predictors of poor outcomes in postoperative patients with GC.

[Table: see text]

[Table: see text]

Phase II study of combination therapy with S-1 and irinotecan in patients with advanced colorectal cancer

BACKGROUND

A combination of irinotecan with continuous intravenous infusions of 5-fluorouracil (5-FU) and leucovorin (LV) is often used to treat advanced colorectal cancer. However, recent concerns about safety and convenience have prompted the development of new oral fluoropyrimidine derivatives and improved regimens. This phase II study evaluated the efficacy and safety of the oral fluoropyrimidine S-1 plus irinotecan in patients with previously untreated advanced or recurrent colorectal cancer.

PATIENTS AND METHODS

Forty eligible patients with histologically confirmed colorectal adenocarcinoma received this treatment. S-1 was administered orally on days 1 to 14 of a 21-day cycle. Patients were assigned on the basis of body surface area (BSA) to receive one of the following oral doses twice daily: 40 mg (BSA < 1.25 m(2)), 50 mg (BSA > or = 1.25 to < 1.50 m(2)), or 60 mg (BSA > or = 1.50 m(2)). Irinotecan (150 mg/m(2)) was administered by intravenous infusion on day 1.

RESULTS

A total of 327 courses of treatment were administered to 40 patients. Five patients had complete responses, and 20 had partial responses. The overall response rate was 62.5% (95% confidential interval, 47.5%-77.5%). Median progression-free survival was 8.0 months (95% confidential interval, 5.2-11.4 months). The rates of grade 3 or 4 toxicity were as follows: neutropenia, 15%; anemia, 7.5%; anorexia, 12.5%; and diarrhea, 7.5%.

CONCLUSIONS

Combined treatment with S-1 and irinotecan is an effective, well tolerated, and convenient regimen in patients with advanced colorectal cancer. Our findings suggest that combined treatment with S-1 and irinotecan is a promising regimen, offering benefits in terms of safety and survival as compared with conventional regimens in patients with advanced colorectal cancer.

Resin adhesion to caries-affected dentine after different removal methods

BACKGROUND

Caries-affected dentine is the common bonding substrate when treating a patient. At present, there are many methods used for caries removal. The aim of this study was to evaluate the microtensile bond strength of two adhesives (Clearfil Protect Bond and OptiBond Solo Plus Total-Etch) to caries-affected dentine after three different caries removal methods.

METHODS

Extracted carious human third molars were used and caries-affected dentine surfaces were obtained from one of the three removal methods: (i) round steel bur in a slow-speed handpiece; (ii) Er:YAG laser; or (iii) 600-grit silicon carbide abrasive paper. Each of the adhesives was used to bond resin composite to the caries-affected dentine according to the manufacturers' instructions. Hourglass-shaped specimens were prepared and stressed in tension at 1mm/min. Data were analysed using two-way analysis of variance and least significant difference test.

RESULTS

Clearfil Protect Bond showed significantly lower bond strength than OptiBond Solo Plus Total-Etch after caries removal with round steel bur, but the opposite was found for specimens treated with silicon carbide abrasive paper. For laser-treated dentine, no significant differences between the adhesives were revealed.

CONCLUSIONS

Besides the differences in adhesives, different caries removal methods seem to influence resin adhesion to caries-affected dentine.