POS0544 INFLUENCE OF EATING HABITS ON FRAILTY AMONG PATIENTS WITH RHEUMATOID ARTHRITIS: KURAMA COHORT

Background:

Rheumatoid arthritis (RA) is a chronic inflammatory disorder that contributes to accelerating frailty, a clinical state of increased vulnerability due to declined physiological function. Although accumulating evidence suggests the importance of nutritional therapy for frailty in the general population, there is little evidence on dietary recommendations for preventing frailty in patients with RA.

Objectives:

The present study aimed to reveal clinical associations between frailty status, eating habits and RA disease activity.

Methods:

We conducted a cross-sectional study of 306 female outpatients enrolled from the KURAMA (Kyoto University Rheumatoid Arthritis Management Alliance) cohort database. The participants were classified into three groups (robust, prefrail and frail) according to simplified frailty scale (SOF index), and dietary data were collected using a self-reported food frequency questionnaire as previously reported. We performed multivariate logistic analyses for the presence of frailty/prefrailty with or without eating habits.

Results:

Frail group showed physical decline such as decreased skeletal muscle index, hand grip strength and walking speed, and DAS28-ESR in the frail group was significantly higher compared to that in the others. In multivariate logistic analysis, the presence of frailty/prefrailty was correlated with DAS28-ESR (OR 1.71, p=0.00004) and methotrexate use (OR 0.47, p=0.0097). Cochran-Armitage trend test also showed that the intake frequency of five ingredients (meat, fish, milk, fruits and vegetables) was inversely associated with the prevalence of frailty/prefrailty. In additional multivariate logistic analyses with dietary habits, habitual intake of fish (at least three times per week), rather than meat or other foods, was independently correlated with the presence of frailty/prefrailty (OR 0.33, p=0.00027).

Conclusion:

Our results suggest that habitual intake of fish, rather than meat or other foods, may be beneficial in preventing frailty among RA patients.

References:

[1]Ferrucci, L. & Fabbri, E. Inflammageing: chronic inflammation in ageing, cardiovascular disease, and frailty. Nat Rev Cardiol 15, 505-522, doi:10.1038/s41569-018-0064-2 (2018).

[2]Hernandez Morante, J. J., Gomez Martinez, C. & Morillas-Ruiz, J. M. Dietary factors associated with frailty in old adults: a review of nutritional interventions to prevent frailty development. Nutrients 11, doi:10.3390/nu11010102 (2019).

Table 1.

Multivariate logistic analysis for RA patients with prefrailty or frailty

variables including eating habitsFish + MeatAllOR (95% CI)P valueOR (95% CI)P valueDAS28-ESR1.78 (1.34 - 2.37)0.000031.73 (1.30 - 2.30)0.00009MTX use0.43 (0.23 - 0.79)0.00550.42 (0.23 - 0.78)0.0050Age (1 year)1.02 (1.00 - 1.05)0.0371.03 (1.01 - 1.06)0.0015PSL use1.23 (0.69 - 2.21)0.491.22 (0.67 - 2.20)0.51Duration of RA (1 year)1.00 (0.98 - 1.02)0.721.00 (0.98 - 1.02)0.84Body mass index1.00 (0.93 - 1.07)0.980.99 (0.92 - 1.07)0.85Biological agents use1.02 (0.60 - 1.72)0.941.04 (0.62 - 1.77)0.87Fish dish0.31 (0.17 - 0.55)0.000040.33 (0.18 - 0.61)0.00027Meat dish0.86 (0.49 - 1.50)0.600.89 (0.51 - 1.57)0.69Milk0.71 (0.41 - 1.24)0.23Vegetable0.95 (0.47 - 1.93)0.89Fruits0.77 (0.41 - 1.42)0.40Figure 1.

The prevalence of prefrailty or frailty for subjects by intake frequency

Acknowledgements:

We thank S. Nakagawa and M. Iida for technical assistance.

Disclosure of Interests:

Masao Katsushima: None declared, Hiroto Minamino: None declared, Mie Torii: None declared, Motomu Hashimoto Speakers bureau: M.H. receives grants and/or speaker fees from Bristol-Meyers, Eisai, Eli Lilly, and Tanabe Mitsubishi., Grant/research support from: M.H. belongs to the department financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei).

KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Wataru Yamamoto: None declared, Ryu Watanabe Grant/research support from: R.W. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei). KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Kosaku Murakami: None declared, Koichi Murata Grant/research support from: K.M. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei).

KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Masao Tanaka Grant/research support from: M.T. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei).

KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Hiromu Ito Speakers bureau: H.I. receives a research grant and/or speaker fee from Bristol-Myers, Eisai, Mochida, Taisho, and Asahi-Kasei., Grant/research support from: H.I. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei). KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Akio Morinobu Speakers bureau: A.M. has received speaking fees and/or research grants from Eli Lilly Japan K.K., Ono Pharmaceutical Co., Pfizer Inc., UCB Japan, AbbVie G.K., Asahi Kasei Pharma and Chugai Pharmaceutical Co. Ltd., Grant/research support from: A.M. has received speaking fees and/or research grants from Eli Lilly Japan K.K., Ono Pharmaceutical Co., Pfizer Inc., UCB Japan, AbbVie G.K., Asahi Kasei Pharma and Chugai Pharmaceutical Co. Ltd.

Abstract P3-03-21: Usefulness of sentinel lymph node biopsy by indocyanine green fluorescence method for cN0 breast cancer patients

Background. Indocyanine green (ICG) fluorescence method (ICG-f) has been recently widely used in sentinel lymph node (SLN) detection. The advantages of ICG-f are no radiation exposure, no limitation to use in high-volume medical centers without radioactive facility, and to confirm lymph flow as a real-time image from outside the body. ICG-f identified an average of 2.3-3.4 SLNs and the detection rate was 99%, compared to 1.7-2 SLNs by RI methods. Long-term observation after SNB using ICG-f has not been reported, including arm lymphedema as the complication of this method.We evaluate the usefulness of SLN biopsy (SNB) for cN0 breast cancer patients from data of multicenter cohort study on long-term results after negative SNB by ICG-f.

Methods. Eleven hundred and thirty-two women were enrolled who had histologically proved clinical stage T1-4, pN0, M0 primary invasive breast cancer with SNB using ICG-f (ICG alone or combination of RI/blue dye method) sparing axillary lymph node dissection from May 2007 to December 2015. This study is retrospective, multicenter cohort study conducted at 6 centers in Japan. Primary endpoint is axillary recurrence rate. We analyzed the correlation with the axillary recurrence and adjuvant systemic therapy, adjuvant radiotherapy, and the clinicopathological characteristics. Secondary endpoint is lymphedema.

Results and Discussion. The median follow-up time was 41 (range 21-117) months, and axillary recurrence was found in 6 patients (0.53%). Five out of 6 patients were not received standard adjuvant systemic therapy or adjuvant radiation therapy after breast conserving surgerybecause of patient's preference or old age. Lymphedema was identified only 4 patients in 632 patients. It is reported that axillary recurrence after SNB was 0.3-1.65%, which was consistent with our result. Lymphedema was not frequent in patients received SNB using ICG-f, because SLNs are removed along with lymphatic ducts in the limited area of axillary adipose tissue.

Conclusion.Axillary recurrence after negative SNB using ICG-f was comparable to RI or blue dye method. It might be important to perform appropriate adjuvant medication or radiation therapy for preventing axillary recurrence after SNB using ICG-f.

Next, ICG-f after neoadjuvant chemotherapy is to be investigated, because itis reported that removing more than 2 SLNs were associated with a lower likelihood of false negative ratio in patients with clinically node-positive disease converted to clinically node-negative after chemotherapy, and ICG-f might overcome this issue.

Citation Format: Maeshima Y, Takahara S, Yamauchi A, Yamagami K, Sugie T, Yamashiro H, Kato H, Torii M, Takada M, Torii M. Usefulness of sentinel lymph node biopsy by indocyanine green fluorescence method for cN0 breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-21.

Abstract PD2-07: Real-time navigation for sentinel lymph node biopsy in breast cancer patients using projection mapping with indocyanine green fluorescence

Background)

Sentinel lymph node (SLN) biopsy using indocyanine green fluorescence (fICG) method showed equal or better identification rate compared with blue dye or radioisotope (RI) method. In the fICG method, lymphatic vessels which drain into the SLNs can be seen through skin or subcutaneous tissue using near infrared camera (Photodynamic Eye®: PDE), and we can easily find the SLNs. However, whenever we observe the fluorescence images, we have to hold the PDE, turn off the operating light, and look at a monitor because fluorescence images cannot be seen directly. Medical imaging projection system (MIPS) is a new device which detects fluorescent emission from the organ and projects their images on the location of the fluorescence emission (Panasonic Connected Solutions Company, Japan). Projected images can be adjusted following the body movement or deformation of the organ. Therefore, MIPS could provide an option for real-time navigation for the SLN biopsy. The aim of this study was to evaluate the clinical utility of the MIPS.

Patients and methods)

Patients with clinically node-negative primary breast cancer underwent the fICG SLN biopsy using MIPS. Primary endpoint was identification rate of the fICG method using MIPS. At first, the study was conducted as an interventional study because the MIPS was the unapproved medical device. After approval of the MIPS, this study was conducted as an observational study. The study protocol was approved by the institutional review board at Kyoto University Hospital. All patients provided informed consent to participate in this study.

Results)

Between March 2016 and May 2017, 39 patients (40 procedures) underwent the fICG method SLN biopsy using MIPS. The median age was 55 years (range 32–74 years), and the median body mass index was 20.4 kg/m2 (range 17.7–27.7 kg/m2). About half had tumor stage T1 (58%) and 8 (20.0%) had DCIS. 8 procedures (20%) were performed after preoperative systemic therapy (PST). As MIPS itself can illuminate the operating field, SLN biopsy using MIPS was successfully performed without operating light in all procedures. At least one SLN was detected using MIPS for all procedures and the identification rate was 100% (95% CI: 91–100%). Median number of SLNs detected by MIPS was 3 (range 1–9) for all procedures, and 3 (range 2–8) for procedures after PST. Two pathologically positive SLNs and one SLN which included isolated tumor cells were detected by MIPS. In 25 procedures, RI was also used. 62 of 97 SLNs detected by MIPS (64%) were also detected by RI. However, no SLNs were detected only by RI.

Conclusions)

Although we still may not be able to avoid RI method because 25/40 (62.5%) procedures required the combined use of RI method, the fICG methods SLN biopsy using MIPS, which showed comparable identification rate of SLN with the conventional methods, could be useful tool with a view of allowing us to perform a real-time navigation surgery.

Acknowledgements)

This study was supported by Acceleration Transformative research for Medical innovation, Japan Agency for Medical Research and Development (AMED).

Citation Format: Takada M, Takeuchi M, Suzuki E, Sato F, Matsumoto Y, Torii M, Sakita-Kawaguchi N, Nakayama Y, Okuda T, Nishino H, Seo S, Hatano E, Toi M. Real-time navigation for sentinel lymph node biopsy in breast cancer patients using projection mapping with indocyanine green fluorescence [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD2-07.

Abstract P4-01-10: Development of photoacoustic vascular imaging system for breast cancer

Background:

Tumor angiogenesis and hypoxia are associated with breast cancer growth and metastasis. Photoacoustic (PA) tomography is an optical imaging technology that visualizes distribution and oxygenation status of hemoglobin with high spatial resolution. Initially we developed a photoacoustic mammography (PAM) having a flat-shaped scanning detector that could detect breast tumors. Nevertheless, the flat-shaped detector array has the drawback of a limited view. Here we developed a novel PAM system with a hemispherical-shaped detector array (HDA), which enables us to identify microvasculatures non-invasively and allow the collection of nearly spatially isotropic three-dimensional reconstructed image of blood vessels. This non-invasive vascular imaging system may be able to characterize tumor angiogenesis and analyze the status of microcirculation. The aim of this study was to analyze the imaging findings of tumor-related vasculature in breast cancer patients.

Patients and method:

A PAM system with HDA has been generated in a cooperation project between Canon Inc., Japan, and Kyoto University. Twenty-two primary breast cancer patients, including 5 patients with non-invasive cancer and 17 patients with invasive cancer, diagnosed between December 2014 and December 2015 underwent the PAM imaging analysis. We also applied the breast deformation algorithm from the breast shape in a MRI image to that in a PA image in order to create a fusion image of the two modalities for the analysis. Features of peri- and intra-tumoral vasculature, and their oxygenation status were evaluated. The study protocol was approved by the institutional review board at Kyoto University Hospital (UMIN000012251). All patients provided informed consent to participate in this study.

Results:

The abnormal peri-tumoral vasculature was detected in 86% of all non-invasive and invasive disease cases. In invasive cancer cases, most tumor-related blood vessels were centripetally directed toward the tumor, and 93% of centripetal blood vessels appeared to be disrupted or rapidly narrowed at the tumor boundary. The centripetal blood vessel structure was frequently observed in invasive cancer compared with non-invasive cancer (61% vs 35%). PA images before and after preoperative chemotherapy were obtained in one case, where intra-tumoral blood vessels became finer after chemotherapy, reflecting normalization of intra-tumoral microcirculation induced by chemotherapy.

Conclusions:

A PAM system with HDA has provided a high-resolution vascular images of primary breast cancers. The morphological differences of peri-tumoral vasculature were observed between invasive disease and non-invasive disease. These results suggest the potential of PA imaging as a non-invasive tool to analyze tumor vasculature of human breast cancers and maybe be helpful for breast cancer diagnosis.

(Acknowledgements)

This work was partially supported by the Innovative Techno-Hub for Integrated Medical Bio-imaging Project of the Special Coordination Funds for Promoting Science and Technology from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.

Citation Format: Toi M, Asao Y, Takada M, Kataoka M, Endo T, Kawashima M, Yamaga I, Nakayama Y, Tokiwa M, Fakhrejahani E, Torii M, Kawaguchi-Sakita N, Kanao S, Matsumoto Y, Yagi T, Sakurai T, Togashi K, Shiina T. Development of photoacoustic vascular imaging system for breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-01-10.

Visualization of tumor-related blood vessels in human breast by photoacoustic imaging system with a hemispherical detector array

Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis.

Abstract P4-03-03: Detection of the tumor vasculature and the hypoxic status of breast lesions using second-generation photoacoustic mammography: An exploratory study

Background: Tumor angiogenesis and hypoxia are associated with breast cancer growth and metastasis. Photoacoustic mammography (PAM) non-invasively visualizes hemoglobin distribution inside the breast by detecting thermoelastic waves from hemoglobin generated by the irradiation of a near-infrared laser pulse. Oxygen saturation (SO2) can be calculated using photoacoustic (PA) signals obtained by two laser pulses of different wavelengths. We further improved the spatial resolution of PAM by approximately 1 mm and enhanced detectability by using a high-sensitivity detector. This new PAM technique can obtain both PAM images and ultrasonography (US) images simultaneously. The aim of this study was to explore the clinical usefulness of this PAM technique.

Patients and methods: Women who had breast lesions were eligible for this study. The participants' lesions were measured using the new PAM technique before they began treatment. The PAM images were evaluated by 5 physicians. First, the lesions were identified using only the PAM images. Second, we used US or contrast-enhanced magnetic resonance images (CE-MRI) to identify the locations of the lesions. Next, we evaluated the photoacoustic (PA) signals based on their locations. Peri-tumoral PA signals were defined as linear signals that congregated in the peri-tumoral area, boundary PA signals were defined as peri-tumoral signals that were disrupted at the lesion's boundaries, and intra-tumoral PA signals were defined as any significant PA signals inside the tumor. SO2 was illustrated using a color scale. The study protocol was approved by the institutional review board at Kyoto University Hospital, Japan (UMIN000007464).

Results: PAM was performed on 48 breast lesions in 45 patients, including 36 invasive carcinoma lesions, 8 ductal carcinoma in situ (DCIS) lesions, and 4 benign lesions. Evaluations of PA signals according to the locations of the lesion, with confirmation from US or CE-MRI, were successfully performed for 38 lesions. Peri-tumoral PA signals were detected in 33 lesions (87%), disrupted boundary PA signals were detected in 30 lesions (79%), and intra-tumoral PA signals were detected in 25 lesions (66%). The detection rates for peri-tumoral, boundary and intra-tumoral PA signals were 94%, 87%, and 65% for invasive carcinoma, and 60%, 40%, and 80% for DCIS, respectively. Intra-tumoral PA signals tended to be weaker than peri-tumoral PA signals in invasive carcinoma lesions, and they often displayed a spotty rather than a linear shape. Intra-tumoral PA signals were observed to have lower SO2 levels than peri-tumoral PA signals in 95% of invasive carcinoma lesions and in 75% of DCIS lesions. Although peri-tumoral and boundary PA signals were also detected in a 38-mm fibroadenoma, the intra-tumoral PA signals displayed a diffuse pattern.

Conclusions: We demonstrated that high spatial resolution and use in combination with US and CE-MRI facilitate the region-specific evaluation of PAM imaging. PAM could become a useful tool for the evaluation of the hypoxic status of tumors by enhancing its sensitivity.

Citation Format: Takada M, Kawashima M, Kataoka M, Kanao S, Yamaga I, Torii M, Tokiwa M, Fakhrejahani E, Sakurai T, Asao Y, Haga H, Shiina T, Togashi K, Toi M. Detection of the tumor vasculature and the hypoxic status of breast lesions using second-generation photoacoustic mammography: An exploratory study. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-03-03.

Involvement of TRPV1 and AQP2 in hypertonic stress by xylitol in odontoblast cells

AIM

To examine the responses of mouse odontoblast-lineage cell line (OLC) cultures to xylitol-induced hypertonic stress.

METHODOLOGY

OLCs were treated with xylitol, sucrose, sorbitol, mannitol, arabinose and lyxose. Cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay. The expression of transient receptor potential vanilloids (TRPV) 1, 3 and 4 was detected using a reverse transcriptase-polymerase chain reaction (RT-PCR) assay. The expression of aquaporin (AQP) 2 was detected using immunofluorescence and Western blotting analysis. The expression of interleukin-6 (IL-6) under xylitol-induced hypertonic stress was assessed using an enzyme-linked immunosorbent assay (ELISA). Small interfering ribonucleic acid (siRNA) for AQP-2 was used to inhibition assay.

RESULTS

Xylitol-induced hypertonic stress did not decrease OLC viability, unlike the other sugars tested. OLCs expressed TRPV1, 3 and 4 as well as AQP2. Xylitol inhibited lipopolysaccharide (LPS)-induced IL-6 expression after 3 h of hypertonic stress. TRPV1 mRNA expression was upregulated by xylitol. Costimulation with HgCl2 (AQP inhibitor) and Ruthenium red (TRPV1 inhibitor) decreased cell viability with xylitol stimulation. OLCs treated with siRNA against TRPV1 exhibited decreased cell viability with xylitol stimulation.

CONCLUSION

OLCs have high-cell viability under xylitol-induced hypertonic stress, which may be associated with TRPV1 and AQP2 expressions.

Abstract P2-03-09: Tissue hemoglobin oxygen saturation measured by photoacoustic mammography correlates with microvasculature properties assessed by histological image analysis, a preliminary study

Background: Photoacoustic mammography (PAM) is a new optical imaging technology with the potential of imaging tumor vasculature in breast cancer.The technique is applicable to the measurement of hemoglobin oxygen saturation (SO2).We have previously published an initial clinical result using a prototype machine (Canon Inc.,Tokyo, Japan) in breast cancer. We have also presented the morphological characteristics of tumor vessels analyzed by automated image processing during AACR annual meeting 2013. Here, we report the oxygenation data obtained by PAM in relation with histological assessment of tumor vasculature and hypoxia.

Methods: Forty-four breast lesions were evaluated by PAM in this IRB approved prospective study at Kyoto University Hospital, Japan. PAM evaluation was performed on both breasts whenever possible.SO2 was calculated in region of interest after the radiologist confirmed the signal was associated with the tumor location in MRI images. For the normal breast, signals obtained at the same depth of the tumor, were selected. Eighty-one histological sections from 20 available invasive carcinoma tissues at the time of this analysis were selected for immunohistochemical assessment of hypoxia by anti -carbonic anhydrase IX (CA IX) and tumor vasculature image analysis using anti-CD31. Five 0.5 mm2 area of each cancer and 3 area of normal mammary tissue associated with the same lesion were randomly selected from different sections. Total vascular area in each square was calculated by using Image Pro-Plus 7.0 software (Media Cybernetics, USA). Tumor-to-normal vascular area ratio (T/N VA) was calculated for each lesion as an index for tumor blood supply.

Results: Patients’ age ranged from 36 to 83 years old. Tumor associated signals were detected by PAM in 18 out of 20 lesions for which tissues were available for histological examination. SO2 in tumor was calculated 70.6% ±13.2 and 83.3% ±10.7 in the normal counterpart. While T/N VA ranged between 0.11 to 1.14, it was almost 3 times lower in lesions with CA IX positive cytoplasmic membrane staining (0.21 vs 0.7, p-value = 0.021 Mann-Whitney Test). Normalized tumor SO2 (tumor SO2/normal counterpart SO2) was significantly lower in the group with lower T/N VA (0.9 vs. 0.8,p-value = 0.045, Student T-test). To better evaluate the accuracy of PAM measurement in calculating SO2,3780 tumor-associated and 2835 normal microvessels were analyzed by image analysis software. Tumor associated vessels had significantly smaller area (p-value<0.001) and vessels with irregular lumens were more frequent in tumor (76.5% vs 19.6% p-value <0.001) compatible with lower SO2 in tumor areas.

Conclusion: Although the future result of our ongoing clinical studies of PAM measurement in breast cancer patients are more than necessary, the strong correlation between histological evaluation of hypoxia and angiogenesis with PAM measurement of oxygenation shows the promising prospective for clinical application of this new technology in breast cancer.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-03-09.

Roxithromycin inhibits tumor necrosis factor-alpha-induced matrix metalloproteinase-1 expression through regulating mitogen-activated protein kinase phosphorylation and Ets-1 expression

BACKGROUND AND OBJECTIVE

In periodontitis, matrix metalloproteinases (MMPs) are upregulated in response to locally released inflammatory cytokines, resulting in pathologic processes. Roxithromycin is a 14-membered ring macrolide antibiotic with broad-spectrum antibacterial effects against oral pathogens and immunomodulatory effects. Recently, we reported that roxithromycin inhibits tumor necrosis factor (TNF)-alpha-induced vascular endothelial growth factor expression in human periodontal ligament (HPDL) cell cultures. In the present study, we examined the effect of roxithromycin on TNF-alpha-induced MMP-1 production by HPDL cells.

MATERIAL AND METHODS

Cultured cells were incubated with 1% fetal bovine serum for 24 h, followed by treatment with 10 ng/ml TNF-alpha, 10 microM roxithromycin, and mitogen-activated protein kinase inhibitor at various concentrations. Culture supernatants and sediments were collected at different time-points and used for enzyme-linked immunosorbent assays, and northern and western blot analyses.

RESULTS

In HPDL cell cultures, roxithromycin strongly inhibited TNF-alpha-induced MMP-1 mRNA expression and production. The inhibition of MMP-1 gene expression by roxithromycin was dependent on de novo protein synthesis and was regulated at the transcriptional level. Roxithromycin significantly inhibited TNF-alpha-induced c-Jun N-terminal kinase activation (JNP) and marginally inhibited extracellular signal-regulated kinase (ERK) 1/2 activation, but not p38 mitogen-activated protein kinase activation. Furthermore, roxithromycin reduced the induction of Ets-1, one of the critical factors in MMP-1 transcription.

CONCLUSION

Roxithromycin inhibits TNF-alpha-mediated MMP-1 induction through the downregulation of ERK1/2 and JNK activation and the subsequent reduction of Ets-1, suggesting that roxithromycin may have therapeutic use in periodontitis and other chronic inflammatory conditions involving MMP-1 induction.

Malaria parasite induces tryptophan-related immune suppression in mice

Plasmodium spp. cause the worst parasitic diseases in humans and evade host immunity in complicated ways. Activated catabolism of tryptophan in dendritic cells is thought to suppress immunity, which is mediated by an inducible rate-limiting enzyme of tryptophan catabolism, indoleamine 2,3 dioxygenase (IDO), via both tryptophan depletion and production of toxic metabolites. In various infections, including malaria, IDO is known to be activated but its biological significance is unclear; therefore, we investigated whether malaria parasites induce IDO to suppress host immune responses. We found that enzymatic activity of IDO was elevated systematically in our mouse malaria model, and was abolished by in vivo IDO inhibition with 1-methyl tryptophan. Experimental infection with Plasmodium yoelii showed that IDO inhibition slightly suppressed parasite density in association with enhanced proliferation and IFN-gamma production by CD4+ T cells in response to malaria parasites. Our observations suggest that induction of IDO is one of the immune mechanisms of malaria parasites.

An online literature mining tool for protein phosphorylation

A web-based version of the RLIMS-P literature mining system was developed for online mining of protein phosphorylation information from MEDLINE abstracts. The online tool presents extracted phosphorylation objects (phosphorylated proteins, phosphorylation sites and protein kinases) in summary tables and full reports with evidence-tagged abstracts. The tool further allows mapping of phosphorylated proteins to protein entries in the UniProt Knowledgebase based on PubMed ID and/or protein name. The literature mining, coupled with database association, allows retrieval of rich biological information for the phosphorylated proteins and facilitates database annotation of phosphorylation features.

Shear modulus and thermal properties of gutta percha for root canal filling

The purpose of this investigation was to investigate the rheological properties of four commercially available gutta perchas for root canal filling. The relaxation modulus [Gr(0): instantaneous shear modulus] and specific volume of their materials were examined. In addition, the quantity of heat was also studied by differential scanning calorimeter. In a lower temperature range than the first-order transition temperature (melting point), the Gr(0) values of each material were almost identical. A marked decrease of Gr(0) was observed at the melting point, and the range of the first-order transition temperature at heating was from 42.0 to 60.0 degrees C. At higher temperatures than the first-order transition temperature of each material, a considerable difference in Gr(0) values was observed. The transition temperatures obtained by the results of the Gr(0), specific volume and quantity of heat agreed with one another. A marked specific volume change was observed at the first-order transition temperature. The technique using melted gutta percha may not be favourable compared with the conventional lateral condensation technique because melted gutta percha undergoes a large amount of shrinkage during setting.

Hand-assisted laparoscopic resection of serous cystadenoma of the pancreas

It is difficult to exclude the possibility of malignancy of pancreatic cystic tumors because a biopsy of the pancreas is hard to obtain. The indication of open surgery for those cystic tumors without evidence of malignancy is controversial. Therefore, laparoscopic or laparoscopically assisted procedure would be an adequate choice of treatment for cystic tumors of the pancreas. Hand-assisted laparoscopic distal pancreatectomy with preservation of the spleen and the splenic artery and vein was performed for two cases of pancreatic cystic tumors. Three ports and one hand port were used. After careful dissection and accurate hemostasis between the pancreas and splenic vessels, laparoscopic distal pancreatectomy was carried out using an endoscopic linear stapler. There were no perioperative complications. The pathological diagnoses were oligocystic serous cystadenoma and solitary cystic serous cystadenoma, respectively. Hand-assisted, spleen-preserving laparoscopic distal pancreatectomy with preservation of the splenic artery and vein is a feasible procedure for the treatment of benign or borderline-malignant cystic lesions of the distal pancreas.

[Studies on the antigens of invasive stages of Plasmodium yoelii and Plasmodium berghei]

OBJECTIVE

To detect the rhoptry and surface proteins of invasive stages of Plasmodium yoelii and P. berghei with monoclonal antibodies.

METHODS

Subcellular localization of antigens was detected by IFA. The antigens of different stages of the two species malaria parasites were analyzed by Western blotting.

RESULTS

The antigens of rhoptry are very complicated. There are similar epitopes of the rhoptry proteins detected between the two species of Plasmodium. The similar epitopes were also detected between ookinetes and merozoites of P. yoelii, and ookinete antigens between the two species. But there are different antigens detected between merozoites and ookinetes in P. yoelii. The sporozoite surface antigen of P. yoelii was not detected in the ookinetes and merozoites in the same species.

CONCLUSION

There are similar epitopes in the rhoptry and surface antigens of different stages and different species of rodent malaria parasites. There are also distinct antigens among them.

The high molecular mass rhoptry protein, RhopH1, is encoded by members of the clag multigene family in Plasmodium falciparum and Plasmodium yoelii

Malarial merozoite rhoptries contain a high molecular mass protein complex called RhopH. RhopH is composed of three polypeptides, RhopH1, RhopH2, and RhopH3, encoded by distinct genes. Using monoclonal antibody-purified protein complex from both Plasmodium falciparum and Plasmodium yoelii, peptides were obtained by digestion of RhopH1 and their sequence determined either by mass spectrometry or Edman degradation. In both species the genes encoding RhopH1 were identified as members of the cytoadherence linked asexual gene (clag) family. In P. falciparum the family members on chromosome 3 were identified as encoding RhopH1. In P. yoelii two related genes were identified and sequenced. One of the genes, pyrhoph1a, was positively identified as encoding RhopH1 by the peptide analysis and the other gene, pyrhoph1a-p, was at least transcribed. Genes in the clag family present in both parasite species have a number of conserved features. The size and location of the P. yoelii protein complex in the rhoptries was confirmed. The first clag gene identified on chromosome 9 was implicated in cytoadherence, the binding of infected erythrocytes to host endothelial cells; this study shows that other members of the family encode merozoite rhoptry proteins, proteins that may be involved in merozoite-erythrocyte interactions. We propose that the family should be renamed as rhoph1/clag.

Iron lactate-induced osteopenia in male Sprague-Dawley rats

Osteopenia was induced in rats fed a diet containing 50,000 ppm (5%) iron lactate for 2 or 4 weeks. Blood chemistry, urinalysis, and bone histomorphometry of the proximal tibial metaphysis were performed. Urinary pyridinoline and deoxypyridinoline and the osteoclast number per bone surface were selected for the measurement of dynamic resorption. The osteoclast surface, eroded surface, and osteoblast surface increased at both ends of the exposure periods, and bone resorption and formation both increased. The bone volume, trabecular thickness, and trabecular number decreased, and the secondary spongiosa of proximal metaphysis showed a marked bone loss. However, no mineralization defect was observed. At the end of the 2-week exposure period, biomarkers of osteoclasts and osteoblasts had increased the most, and the osteoblast surface, osteoclast surface, and osteoclast number per bone surface increased with prolonged exposure. The pathological changes of the bone lesion in iron lactate-overloaded rats were similar to those in rats of the osteoporotic model, because they consisted of changes reflecting the increase of bone resorption and formation without an osteomalacic change. However, the decline of serum parathyroid hormone (PTH) levels was different from that of the osteoporosis model rat. We concluded iron-induced bone lesions probably differ from those of low turnover bone diseases.

von Willebrand Factor A domain-related protein, a novel microneme protein of the malaria ookinete highly conserved throughout Plasmodium parasites

The mosquito-invasive form of the malarial parasite, the ookinete, develops numerous secretory organelles, called micronemes, in the apical cytoplasm. Micronemal proteins are thought to be secreted during midgut invasion and to play a crucial role in attachment and motility of the ookinete. We found a novel ookinete micronemal protein of rodent malarial parasite Plasmodium berghei, named P. berghei von Willebrand factor A domain-related protein (PbWARP), and report it here as a putative soluble adhesive protein of the ookinete. The PbWARP gene contained a single open reading frame encoding a putative secretory protein of 303 amino acids, with a von Willebrand factor type A module-like domain as a main component. Western blot analysis demonstrated that PbWARP was firstly produced 12 h after fertilization by maturing ookinetes as SDS-resistant complexes. Recombinant PbWARP produced with a baculovirus system also formed SDS-resistant high-order oligomers. Immuno-electron microscopic studies showed that PbWARP was randomly distributed in the micronemes. PbWARP homologues also exist in human malarial parasites, Plasmodium falciparum and Plasmodium vivax. Highly conserved primary structures of PbWARP homologues among these phylogenetically distant Plasmodium species suggest their functional significance and the presence of a common invasion mechanism widely utilized throughout Plasmodium parasites.

Development of a method for the in vitro production of Plasmodium vivax ookinetes

We developed a method for the in vitro production of mature Plasmodium vivax ookinetes. Gametocytemic blood was collected from 98 P. vivax-infected patients reporting to malaria clinics in Maesod and Maekasa Districts, Tak Province, Thailand. Briefly, gametogenesis was induced using xanthurenic acid and parasites were separated by density gradient centrifugation and then cultured in RPMI-1640, pH 7.8-8.2. At the same time that blood was collected, 200 Anopheles dirus mosquitoes were allowed to feed on each patient. Mosquito midguts were removed 2-36 hr postfeeding, and gut contents were smeared onto glass slides, as were cultured samples from varying time points. Slides were stained with Giemsa, and the in vitro and mosquito development of ookinetes compared. Mature ookinetes were produced in 48.0% (47/98) of in vitro cultures, with a total yield ranging from 10 to 248,500 (mean = 15,523, median = 600) ookinetes produced per 5 ml blood. The temporal development and the morphology of the P. vivax ookinetes produced in vitro was similar to that observed in the A. dirus mosquitoes. The method that we describe is simple, can be used at remote sites without sophisticated equipment, and yields high numbers of clean ookinetes. This method of producing mature P. vivax ookinetes will be a useful tool for studies on ookinetes in P. vivax endemic regions.

Inhibition by carbapenem antibiotic imipenem of intestinal absorption of valproic acid in rats

The concomitant use of carbapenem antibiotics with valproic acid has been prohibited because panipenem induced a decrease in plasma concentration of valproic acid in epileptic patients during valproic acid therapy. To clarify the possible mechanism of the carbapenem-valproic acid interaction, we investigated the effect of imipenem on the pharmacokinetic behaviour of valproic acid in rats. Co-administration of imipenem (30 mg kg(-1), i.v.) induced a decrease in the peak plasma concentration of valproic acid after oral administration. However, the imipenem-induced decrease in plasma concentrations of valproic acid was not observed within 60 min after intravenous injection of valproic acid. By utilizing in-situ vascular and luminal perfused small intestine, it was confirmed that absorption of valproic acid from the luminal to the vascular perfusate was decreased in the presence of imipenem (0.5 mM) in the vascular perfusate. The everted gut sac method was used to determine the effect of imipenem on active transport of valproic acid. The accumulation of valproic acid on the serosal side of the intestinal sac against the concentration gradient was reduced by lactic acid that inhibits the carrier-mediated transport of valproic acid across the intestinal brush-border membrane. However, imipenem did not affect the active transport of valproic acid. Therefore, the inhibition by imipenem of valproic acid absorption may be caused by a mechanism different from that of lactic acid. In conclusion, imipenem inhibits the intestinal absorption of valproic acid, which contributes to the decrease in plasma concentration of valproic acid after oral administration.

Twenty-six-week carcinogenicity study of sulfamethoxazole in CB6F1-Tg-rasH2 mice

Sulfamethoxazole (SMX), a hormone-mediated rodent-specific nongenotoxic carcinogen, was administered to CB6F1 mice carrying a human prototype c-Ha-ras gene (Tg-rasH2) at doses of 0, 25, 100 or 400 mg/kg/day and to the wild-type mice at a dose of 400 mg/kg/day in feed for 26 weeks to evaluate the carcinogenicity and to validate the Tg-rasH2 model. N-Methyl-N-nitrosourea was administered at an intraperitoneal dose of 75 mg/kg to Tg-rasH2 as a positive control and the experimental system was confirmed to be valid. Histopathological examination revealed adenomas of the lung and Harderian gland and hemangiosarcoma of the spleen at low frequencies in the Tg-rasH2 treated with SMX; however, no statistically significant differences were observed either in the onset or prevalence rates of these neoplasms compared with that in the control group. Between the wild-type mice and Tg-rasH2, the onset rate and prevalence of the neoplasms were not significantly different, but the neoplasms tended to be more frequent in Tg-rasH2 mice showing a sensitivity to tumorigenicity. Follicular epithelial cell hyperplasia was observed in the thyroid gland in the groups of Tg-rasH2 given 100 mg/kg SMX or more, but no neoplastic lesion was observed. SMX was judged to be negative for carcinogenic potential in Tg-rasH2 in the present study.

Regulation of interleukin-6 expression in human dental pulp cell cultures stimulated with Prevotella intermedia lipopolysaccharide

Interleukin (IL)-6 expression in human dental pulp cell cultures after stimulation with Prevotella intermedia lipopolysaccharide (LPS) was investigated by Northern blot analysis, enzyme immunoassay, and bioassay. The IL-6 mRNA expression began to increase after 1 hr and continued after up to 8 hr of exposure on stimulation with 10 microg/ml of P. intermedia LPS. The bioactivity was dose-dependent on the concentration of P. intermedia LPS (0 to 100 microg/ml). The IL-6 mRNA expression was inhibited by actinomysin D and super-induced by cycloheximide. Anti-CD14 monoclonal antibody (MY4) inhibited the IL-6 mRNA expression when administered at a 0.5 microg/ml concentration before stimulation with P. intermedia LPS at 1 microg/ml. The immunoregulatory cytokines (interferon-gamma, IL-10, and IL-4) inhibited LPS-induced IL-6 production with a combined treatment. These results suggest the IL-6 expression by pulp cell cultures is CD14-dependent and regulated at the transcriptional level, and a combined treatment with immunoregulatory cytokines may be effective for control of pulpal inflammation due to P. intermedia LPS.

Antibodies to malaria vaccine candidates Pvs25 and Pvs28 completely block the ability of Plasmodium vivax to infect mosquitoes

Transmission-blocking vaccines are one strategy for controlling malaria, whereby sexual-stage parasites are inhibited from infecting mosquitoes by human antibodies. To evaluate whether the recently cloned Plasmodium vivax proteins Pvs25 and Pvs28 are candidates for a transmission-blocking vaccine, the molecules were expressed in yeast as secreted recombinant proteins. Mice vaccinated with these proteins adsorbed to aluminum hydroxide developed strong antibody responses against the immunogens, although for Pvs28, this response was genetically restricted. Antisera against both recombinant Pvs25 and Pvs28 recognized the corresponding molecules expressed by cultured sexual-stage parasites isolated from patients with P. vivax malaria. The development of malaria parasites in mosquitoes was completely inhibited when these antisera were ingested with the infected blood meal. Pvs25 and Pvs28, expressed in Saccharomyces cerevisiae, are as yet the only fully characterized transmission-blocking vaccine candidates against P. vivax that induce such a potent antiparasite response.

[Prevention and care management of influenza infection in institutions for the elderly and high risk groups]

Influenza infection is a serious problem in institutions for the elderly and those with increased risk factors because of the high pneumonia complication rate and a significant increase in mortality. An outbreak of influenza is mainly caused by contact from the staff to residents, therefore the health care of the staffs and prevention of influenza should be a high priority in institutions such as nursing homes. To prevent influenza epidemics, institutionalised elderly and high risk groups should be vaccinated more actively. The rapid test for diagnosis of influenza viral infection permits the timely administration of antiviral agents and infection control among institutionalised elderly and high risk groups. Amantadine and neuraminidase inhibitors could be used for treatment and prophylaxis of influenza among institutionalised elderly and high risk group patients.

Micronemal transport of Plasmodium ookinete chitinases to the electron-dense area of the apical complex for extracellular secretion

Plasmodium ookinetes secrete chitinases to penetrate the acellular, chitin-containing peritrophic matrix of the mosquito midgut en route to invasion of the epithelium. Chitinases are potentially targets that can be used to block malaria transmission. We demonstrate here that chitinases of Plasmodium falciparum and P. gallinaceum are concentrated at the apical end of ookinetes. The chitinase PgCHT1 of P. gallinaceum is present within ookinete micronemes and subsequently becomes localized in the electron-dense area of the apical complex. These observations suggest a pathway by which ookinetes secrete proteins extracellularly.

Polymerization Contraction Stress of Resin Composite Restorations in a Model Class I Cavity Configuration Using Photoelastic Analysis

PURPOSE

An important factor that contributes to deterioration of resin composite restorations is contraction stress that occurs during polymerization. The purpose of this article is to familiarize the clinician with the characteristics of contraction stress by visualizing the stresses associated with this invisible and complex phenomenon.

MATERIALS AND METHODS

Internal residual stresses generated during polymerization of resin composite restorations were determined using micro-photoelastic analysis. Butt-joint preparations simulating Class I restorations (2.0 mm x 5.0 mm, 2.0 mm in depth) were prepared in three types of substrates (bovine teeth, posterior composite resin, and transparent composite resin) and were used to examine contraction stress in and around the preparations. Three types of composite materials (a posterior composite, a self-cured transparent composite, and a light-cured transparent composite) were used as the restorative materials. The self-cured composite is an experimental material, and the others are commercial products. After treatment of the preparation walls with a bonding system, the preparations were bulk-filled with composite. Specimens for photoelastic analysis were prepared by cutting sections perpendicular to the long axis of the preparation. Fringe patterns for directions and magnitudes of stresses were obtained using transmitted and reflected polarized light with polarizing microscopes. Then, the photoelastic analysis was performed to examine stresses in and around the preparations.

RESULTS

When cavity preparations in bovine teeth were filled with light-cured composite, a gap was formed between the dentinal wall and the composite restorative material, resulting in very low stress within the restoration. When cavity preparations in the posterior composite models were filled with either self-cured or light-cured composite, the stress distribution in the two composites was similar, but the magnitude of the stress was greater in the light-cured material. When preparations in the transparent composite models were filled with posterior composite and light-cured transparent composite material, significant stress was generated in the preparation models simulating tooth structure, owing to the contraction of both restorative materials.

CLINICAL SIGNIFICANCE

Polymerization contraction stress is an undesirable and inevitable characteristic of adhesive restorations encountered in clinical dentistry that may compromise restoration success. Clinicians must understand the concept of polymerization contraction stress and realize that the quality of composite resin restorations depends on successful management of these stresses.

Effects of roxithromycin on tumor necrosis factor-alpha-induced vascular endothelial growth factor expression in human periodontal ligament cells in culture

BACKGROUND

Aberrant angiogenesis is associated with lesion formation in chronic periodontitis. However, little is known about the mediators that contribute to angiogenesis or about therapeutic agents that control the production of the mediators. Roxithromycin (RXM), which is a new 14-member macrolide antibiotic, has a wide antibacterial spectrum against oral pathogens and an immunomodulatory effect. In the present study, we examined the effects of RXM on tumor necrosis factor (TNF)-alpha-induced vascular endothelial growth factor (VEGF) in human periodontal ligament (HPDL) cells. In addition, the effect of RXM on VEGF expression in HPDL cells was examined.

METHODS

HPDL cells were plated at 5 x 10(5) cells/ml in 150 cm2 cell culture dishes. The confluent-stage cells were pretreated with or without 10 microg/ml of RXM or other antibiotics in 1% FBS-containing alpha-MEM for 24 hours, followed by simultaneous treatment with 10 ng/ml of TNF-alpha and 10 microg/ml of these antibiotics. After incubation for various periods, the culture supernatants and sediments were collected and analyzed by ELISA, Northern blot, and gel shift assays.

RESULTS

VEGF mRNA and its protein were constitutively expressed in HPDL cells, and the level of expression was markedly enhanced by stimulation with TNF-alpha. RXM strongly inhibited the expression of VEGF mRNA and the production of VEGF. Furthermore, RXM suppressed activation of transcription factors AP-1 and SP-1, which were critical factors in VEGF transcription, in TNF-alpha-stimulated HPDL cells.

CONCLUSION

These results indicate that TNF-alpha, one of the proinflammatory cytokines implicated in the pathogenesis of periodontitis, induces excess induction of VEGF in HPDL, which may account for increased angiogenesis in periodontitis lesions. Interestingly, the antibiotic roxithromycin inhibits TNF-mediated VEGF induction, suggesting its possible therapeutic utility in periodontitis and other chronic inflammatory conditions involving VEGF induction.

The role of vascular endothelial growth factor in human dental pulp cells: induction of chemotaxis, proliferation, and differentiation and activation of the AP-1-dependent signaling pathway

Vascular endothelial growth factor (VEGF) is a potent mitogen in endothelial cells, but little is known about its activity in other cell types. To clarify the role of VEGF in human dental pulp cells and pulp tissue, we investigated the effects of VEGF on the chemotaxis, proliferation, and differentiation of human dental pulp cells. VEGF induced a strong chemotactic response in human dental pulp cells in a dose-dependent manner. VEGF also marginally enhanced the proliferation of human dental pulp cells and induced an increase in alkaline phosphatase in human dental pulp cells. However, these effects of VEGF were not observed in reference to human skin fibroblasts. Analyses by the reverse-transcription/polymerase-chain-reaction method and flow cytometry showed that the mRNAs of two VEGF receptors, fins-like tyrosine kinase and kinase insert domain-containing receptor, were expressed in human dental pulp cells, whereas only fms-like tyrosine kinase mRNA was expressed in human skin fibroblasts. VEGF induced the activation of activator protein 1 (AP-1) and c-fos mRNA expression in human dental pulp cells. The AP-1 inhibitor curcumin strongly inhibited VEGF-induced alkaline phosphatase production in human dental pulp cells. In addition, VEGF antisense oligonucleotide suppressed the production of VEGF and alkaline phosphatase in human dental pulp cells. These results suggest that VEGF produced by human dental pulp cells acts directly upon human dental pulp cells in an autocrine manner, and may promote the chemotaxis, proliferation, and/or differentiation of human dental pulp cells via the utilization of kinase insert domain-containing receptor and in part through AP-1 by increasing c-fos.

Antibacterial activities and release kinetics of a newly developed recoverable controlled agent-release system

We attempted to develop a resin with a recoverable antibacterial activity based on the desorption/adsorption of a cationic bactericide by the ion-exchange mechanism. The aims of this study were to investigate the release kinetics of the agent and the antibacterial activity of this newly designed resin system. An experimental resin was prepared by the addition of methacrylic acid as a cation-exchanger and a cationic antibacterial agent, cetylpyridinium chloride (CPC), to triethyleneglycol dimethacrylate. The amount of CPC desorbed from the experimental resin into buffer solutions at pH 4-8 was measured. The adsorption of CPC to control resin and re-adsorption of CPC to the experimental resin, which had once desorbed the agent, were also determined. The antibacterial activity of experimental resin against Streptococcus mutans was evaluated, and the relationship between bacterial acid production and antibacterial effect was assessed. The experimental resin desorbed CPC at pH < or = 6, and the amount of agent desorbed increased with increasing acidity. The control resin adsorbed CPC when immersed in CPC aqueous solution at a rate determined by the concentration of the agent and immersion time. The experimental resin, once desorbed CPC, could re-adsorb the bactericide by being exposed to a solution of the agent. Less plaque formed on the experimental resin, and the growth and survival of S. mutans was inhibited in the condition in which acid was produced. These results demonstrate that the resin system proposed was able to desorb and re-adsorb the cationic bactericide by an ion-exchange mechanism and could show an inhibitory effect on S. mutans growth and plaque formation.

Prostaglandin E2 predominantly induces production of hepatocyte growth factor/scatter factor in human dental pulp in acute inflammation

Hepatocyte growth factor (HGF), which is also known as the scatter factor, is a broad-spectrum and multifunctional cytokine, mediates epithelial-mesenchyme interaction, and is shown to be involved in the development and regeneration of various tissues, including tooth. Here, we report that HGF was present in adult human dental pulps, and its levels increased during acute inflammation of the tissue. Levels of HGF mRNA in dental pulps also increased with inflammation, as determined by reverse-transcription/polymerase chain-reaction. The production of HGF in fibroblasts from dental pulps in culture was dose-dependently stimulated by inflammatory cytokines such as interleukin (IL)-1alpha and tumor necrosis factor (TNF)-alpha, and by prostaglandin (PG) E2, as determined by an enzyme-linked immunosorbent assay. We also showed that indomethacin did not affect the increase in HGF production by the cells with IL-1alpha, TNF-alpha, and PGE2. The levels of HGF mRNA in the cells were simultaneously increased by these stimulants, as determined by Northern blotting. Since the production of PGs is known to increase at the beginning of inflammation, PGE2 may be involved in the regeneration of dental pulps by the induction of HGF expression after inflammation.

Inflammatory cytokine production and specific antibody responses to lipopolysaccharide from endodontopathic black-pigmented bacteria in patients with multilesional periapical periodontitis

We examined the induction of the cytokines interleukin (IL)-1 beta, IL-6, and IL-8 by lipopolysaccharides (LPSs) from several species of possible endodontopathic black-pigmented bacteria. Studies were conducted in human whole blood cultures from six patients (two from each group) with differing numbers of periapical periodontitis lesions (i.e. patients with radiographically clear periapical lesions in 10 or more teeth (high-lesion group, n = 4), in one or two teeth (low-lesion group, n = 6), and six healthy volunteers with no periapical lesions (no lesion group)). LPS from Prevotella intermedia ATCC 25611, Porphyromonas gingivalis 381, and Prophyromonas endodontalis ATCC 27067 induced a higher IL-8 response in the subjects of the high-lesion group, compared with the subjects of the other two groups. To ascertain the degree of sensitization by test bacteria, we examined the reactivities of antibodies in serum and saliva from the subjects to different bacterial species. LPS from P. gingivalis reacted strongly with sera from the high-lesion group. Thus, LPS from black-pigmented bacteria may be involved in multilesional periapical periodontitis by inducing particular cytokines and/or humoral immune responses.

Comparison of polymerization contraction stresses between self- and light-curing composites

OBJECTIVES

The objective of this study was to examine the distributions and the magnitudes of the internal stresses in self- and a light-curing composite restorations resulting from polymerization shrinkage.

METHODS

Butt-joint box-shaped cavities (5.0 x 2.0 mm2, 2.0 mm in depth) prepared in composite molds were filled with either a self- or light-curing transparent resin composite. The restorations were cross-sectioned perpendicular to the longitudinal axes of the cavities and observed using polarizing microscopes. The principal stresses in the restorations, normal and shear stresses at the cavity wall were evaluated by photoelastic analysis.

RESULTS

The distributions of the principal stresses and the stresses generated at the cavity wall in both the self- and the light-curing composite restorations were similar. The maximum stress generated at the cavity wall in the light-curing composite restorations was twice as large as that seen in the self-curing restorations.

CONCLUSIONS

The results of this study indicated that the difference in the magnitude of the internal stresses between self- and light-curing composites was not related to the distribution of the stresses. The velocity of polymerization appeared to be the most important factor contributing to the magnitude of the internal stresses generated in the composite restorations in this study.

Facilitatory and inhibitory effects of beta-endorphin on lordosis in female rats: relation to time of administration

The purpose of the present study was to investigate the effect of time of beta-endorphin (beta-EP) administration on lordosis in ovariectomized female rats injected subcutaneously (sc) with estradiol benzoate (EB) and progesterone (Prog). Intracerebroventricular (icv) injections of beta-EP and naloxone (NLX), an opioid receptor antagonist, were administered at the various stages of sc steroid hormone priming. Facilitation of lordosis induced by 10 microg beta-EP was observed exclusively within the initial 6 h of estrogen action, after which inhibition of lordosis occurred. At 12 h after EB priming, at the time of sc Prog treatment (or 43 h after EB priming), icv injection of 10 microg beta-EP significantly inhibited lordosis. Lordosis was significantly facilitated by icv injections of 1 and 10 microg beta-EP at the time of sc EB priming, but not by 0.1 microg beta-EP. A dose-response relationship was identified for lordosis in experimental animals receiving icv injection of beta-EP. Lordosis was inhibited by icv injections of 1 and 10 microg beta-EP at 1 h before the test (or 47 h after EB priming). Lordosis was significantly inhibited by icv injection of NLX at all stages. From the present results, it seems that two different mechanisms are involved in endorphinergic modulation of rats' sexual receptivity: (a) the endorphinergic system at the initial stages of estrogen action facilitates the estrogen activation of lordosis; (b) the endorphinergic system at the final stages of steroid action inhibits lordosis. Moreover, there exists a critical time between 6 and 12 h after estrogen priming for endorphinergic mediation to modulate estrogen action.

Lipopolysaccharide enhances the production of vascular endothelial growth factor by human pulp cells in culture

We investigated whether vascular endothelial growth factor (VEGF) production by human pulp cells (HPC) is regulated by lipopolysaccharide (LPS) in relation to the pathogenesis of pulpitis. Although HPC incubated with medium alone only marginally expressed VEGF mRNA and produced a low level of VEGF as detected by enzyme-linked immunosorbent assay, the VEGF mRNA expression and VEGF production were markedly enhanced upon stimulation with LPS from Escherichia coli. Prevotella intermedia LPS, phorbol 12-myristate 13-acetate, and interleukin-6 also induced VEGF mRNA expression in HPC. A simian virus 40-infected HPC line also exhibited increased VEGF mRNA expression in response to E. coli LPS, but lung and skin fibroblasts did not. Fetal bovine serum (FBS) increased the sensitivity of HPC to LPS in a dose-dependent manner. HPC did not express membrane CD14 on their surfaces. However, the anti-CD14 monoclonal antibody MY4 inhibited VEGF induction upon stimulation with LPS in HPC cultures in the presence of 10% FBS but not in the absence of FBS. LPS augmented the VEGF production in HPC cultures in the presence of recombinant human soluble CD14 (sCD14). To clarify the mechanisms of VEGF induction by LPS, we examined the possible activation of the transcription factor AP-1 in HPC stimulated with LPS, by a gel mobility shift assay. AP-1 activation in HPC was clearly observed, whereas that in skin fibroblasts was not. The AP-1 inhibitor curcumin strongly inhibited LPS-induced VEGF production in HPC cultures. In addition, a protein synthesis inhibitor, cycloheximide, inhibited VEGF mRNA accumulation in response to LPS. These results suggest that the enhanced production of VEGF in HPC induced by LPS takes place via an sCD14-dependent pathway which requires new protein synthesis and is mediated in part through AP-1 activation.

Sequence polymorphism in two novel Plasmodium vivax ookinete surface proteins, Pvs25 and Pvs28, that are malaria transmission-blocking vaccine candidates

BACKGROUND

For many malarious regions outside of Africa, development of effective transmission-blocking vaccines will require coverage against both Plasmodium falciparum and P. vivax. Work on P. vivax transmission-blocking vaccines has been hampered by the inability to clone the vaccine candidate genes from this parasite.

MATERIALS AND METHODS

To search for genes encoding the ookinete surface proteins from P. vivax, the DNA sequences of the eight known proteins in the P25 subfamily (Pfs25, Pgs25, Pys25, Pbs25) and in the P21/28 subfamily (Pfs28, Pgs28, Pys21, Pbs21) of zygote/ookinete surface proteins were aligned. Regions of highest identity were used to design degenerate PCR oligonucleotides. Genomic DNA from the Sal I strain of P. vivax and genomic and splinkerette DNA libraries were used as PCR templates. To characterize the polymorphisms of Pvs25 and Pvs28, these two genes were PCR amplified and the DNA sequences were determined from genomic DNA extracted from patients infected with P. vivax.

RESULTS

Analysis of the deduced amino acid sequence of Pvs28 revealed a secretory signal sequence, four epidermal growth factor (EGF)-like domains, six copies of the heptad amino acid repeat (GSGGE/D), and a short hydrophobic region. Because the fourth EGF-like domain has four rather than six cysteines, the gene designated Pvs28 is the presumed homologue of P21/28 subfamily members. Analysis of the deduced amino acid sequence of Pvs25 revealed a similar structure to that of Pvs28. The presence of six rather than four cysteines in the fourth EGF-like domain suggested that Pvs25 is the homologue of P25 subfamily members. Several regions of genetic polymorphisms in Pvs25 and Pvs28 were identified in field isolates of P. vivax.

CONCLUSIONS

The genes encoding two ookinete surface proteins, Pvs28 and Pvs25, from P. vivax have been isolated and sequenced. Comparison of the primary structures of Pvs25, Pvs28, Pfs25, and Pfs28 suggest that there are regions of genetic polymorphism in the P25 and P21/28 subfamilies.