Effect of explaining radiographic information to the patient before third molar surgery

OBJECTIVES

The aim of this study was to compare patient satisfaction with the pre-operative information before and after explaining the radiograph and to compare patient satisfaction with the radiographic information when based on a digital or a conventional image, as well as on extraoral or intraoral images.

METHODS

263 patients (with 301 mandibular third molars) were given pre-operative information by one of two trained scholar students before removal of the third molar. The course of the surgery and possible post-operative complications and risks were explained to the patient. The patients rated their satisfaction with the information on a 100 mm visual analogue scale (VAS). The radiograph was displayed and the radiographic information was explained to the patient, with emphasis on tooth-specific risk factors. The patients again rated their satisfaction on a VAS.

RESULTS

There was no significant difference in patient satisfaction score before (mean VAS = 92.5 mm) and after (mean VAS = 91.7 mm) the radiographic information was explained (P = 0.15). No difference in satisfaction was found between patients who were shown either digital or conventional images or between patients who were shown either extraoral or intraoral images (P > 0.5).

CONCLUSIONS

No additional patient satisfaction was obtained by showing and explaining the radiograph to the patient before lower third molar surgery. If the dentist still wishes to show the patient the radiograph, the type of image seems not to be important.

A novel small molecule Met inhibitor, PF2362376, exhibits biological activity against osteosarcoma

The receptor tyrosine kinase Met is dysregulated in several human cancers including osteosarcoma (OSA) in which overexpression is a negative prognostic indicator and enforced Met expression in normal osteoblasts leads to genomic instability and malignant transformation. Met is also known to be inappropriately expressed in canine OSA tumour samples and cell lines. The purpose of this study was to evaluate the potential utility of an orally bioavailable small molecule Met inhibitor, PF2362376, against canine OSA cell lines as a prelude to future clinical work. PF2362376 inhibited phosphorylation of Met, Gab-1, Erk and Akt, but not of Src or STAT3. Furthermore, PF2362376 inhibited proliferation of canine OSA cell lines and induced cell death at biologically achievable concentrations. Last, activities associated with Met signalling including migration, invasion, branching morphogenesis and colony formation in soft agar were blocked by PF2362376. These studies support the notion that Met is a relevant target for therapeutic intervention in OSA.

Prevalence of Yersinia enterocolitica shedding and bioserotype distribution in Ontario finisher pig herds in 2001, 2002, and 2004

We investigated characteristics of Yersinia enterocolitica infection in Ontario finisher pig herds. Our specific objectives were to estimate or test: prevalence of Y. enterocolitica shedding in finisher pigs, bioserotype distribution, agreement between the herd-level tests based on sampling pig and pooled fecal samples, whether bioserotypes cluster by farms, and whether Y. enterocolitica-positive herds cluster spatially. In total, 3747 fecal samples were collected from 100 farms over the years 2001, 2002, and 2004 (250 total herd visits). Fecal samples were tested by culture and positive isolates were biotyped and serotyped. Apparent pig-level prevalence of Y. enterocolitica was 1.8%, 3.2%, and 12.5% in 2001, 2002, and 2004, respectively. Estimated true pig-level prevalence of Y. enterocolitica was 5.1%, 9.1%, and 35.1% in 2001, 2002, and 2004, respectively. Herd-level prevalence was 16.3%, 17.9%, and 37.5% in 2001, 2002, and 2004, respectively. In all years, the most common bioserotype was 4, O:3, followed by bioserotype 2, O:5,27. Kappa between herd-level status based on pig and pooled samples ranged between 0.51 and 0.68 for biotype 1A and bioserotype 4, O:3, respectively. For 4, O:3, a significant bias in discordant pairs was detected, indicating that pig samples were more sensitive than pooled samples in declaring a herd as positive. Farms tended to be repeatedly positive with the same bioserotype, but positive study farms did not cluster spatially (suggesting lack of between herd transmission and lack of a common geographic risk factor).

Molecular bases for sensitivity to figitumumab (CP-751,871) in NSCLC

8091

Background: Signaling of Insulin like Growth Factors (IGFs) through the IGF type 1 receptor (IGF-IR) induces tumor resistance to cancer therapy. Bioavailability of IGFs is regulated by IGF-binding proteins (IGFBP), of which IGFBP3 is the most abundant. Figitumumab (F) (CP-751,871), a specific IGF-IR inhibitor, has shown phase 2 activity in NSCLC in some histologies (i.e., squamous cell and adenocarcinoma) but not others (i.e, large cell or NOS tumors). Methods: Protein expression of members of the IGF-IR pathway, EGFR and differentiation markers was determined in core biopsies from 230 NSCLC pts, including 52 pts enrolled in F trials. Plasma concentration of IGF-1 and related proteins was determined in 159 NSCLC pts in F trials. Gene expression profiling was conducted in 35 NSCLC cell lines treated with F. Results: Squamous NSCLC had the highest IGF-IR expression (p=0.057). An association with better outcome was seen for E-cadherin expression (HR =0.62, 0.46–0.82 95% CI, p=0.005) and clustering by E-cadherin levels revealed a strong correlation between IGF-IR and EGFR expression in the high E-cadherin group (p<0.001). This subset included 73% of the squamous cell tumors investigated (N=44). Plasma levels of free IGF-1 (fIGF-1) were low and not predictive of response in squamous cell. In contrast, pts with adenocarcinoma had high plasma fIGF-1 levels (p=0.06) that correlated with vimentin expression (Rho=0.732, p=0.06), and both fIGF-1 and vimentin were predictive of F clinical benefit (p=0.03). Large cell/NOS NSCLC expressed the highest levels of vimentin (p<0.001) but had low E-cadherin and IGF-IR expression and low fIGF-1 plasma levels. Analysis of anchorage independent growth in NSCLC cell lines confirmed that F activity is independently associated to IGF-IR overexpression (p=0.02) and IGFBP3 under-expression (p=0.009). Conclusions: IGF-IR overexpression and increased free IGFs/low IGFBP are key independent mechanisms of sensitivity to F in NSCLC of squamous and adenocarcinoma cell histologies.

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Chemical contamination assessment of Gulf of Mexico oysters in response to hurricanes Katrina and Rita

Hurricane Katrina made landfall on August 29, 2005 and caused widespread devastation along the central Gulf Coast states. Less than a month later Hurricane Rita followed a similar track slightly west of Katrina's. A coordinated multi-agency response followed to collect water, sediment and tissue samples for a variety of chemical, biological and toxicological indicators. The National Oceanic and Atmospheric Administration's National Status and Trends Program (NS&T) participated in this effort by measuring chemical contamination in sediment and oyster tissue as part of the Mussel Watch Program, a long-term monitoring program to assess spatial and temporal trends in a wide range of coastal pollutants. This paper describes results for contaminants measured in oyster tissue collected between September 29 and October 10, 2005 and discusses the results in the context of Mussel Watch and its 20-year record of chemical contamination in the region and the nation. In general, levels of metals in oyster tissue were higher then pre- hurricane levels while organic contaminants were at or near record lows. No contaminant reported here exceeded the FDA action level for food safety.

Patient discomfort and retakes in periapical examination of mandibular third molars using digital receptors and film

OBJECTIVE

The aim was to compare patient discomfort and evaluate the frequency of retakes using intraoral digital receptors and conventional film for radiographic examination of mandibular third molars.

STUDY DESIGN

Both mandibular third molar regions were examined in 110 patients with 2 of 5 digital intraoral receptors. Discomfort was scored on a visual analog scale (VAS) for each receptor and for film as a reference. If the whole tooth was not imaged on the digital image, a retake was performed using film. t Tests evaluated differences in VAS score, chi-squared tests evaluated differences in frequency of remakes, and logistic regression analyses evaluated factors predisposing for retake.

RESULTS

No significant difference existed in VAS scores between right and left sides for film (P = .24). The digital receptors were more uncomfortable than film (P < .001), and CDR-APS was more uncomfortable than Digora (P = .049) and Vista (P = .002). The frequency of retakes was higher for solid-state sensors than photostimulable phosphor plates (PSPs) (P < .018). Gender (P = .022), type of receptor (P < .021), and VAS score (P = .001) were predisposing factors for a retake.

CONCLUSION

Patients accepted film better than digital intraoral receptors, and retake frequency was lower for PSPs compared with solid-state sensors.

185 THE PORCINE EPIBLAST AND NOT THE INNER CELL MASS HAS DEVELOPED CONVENTIONAL PATHWAYS FOR REGULATION OF PLURIPOTENCY

Pluripotency in mice and human embryonic stem cells is regulated by a number of transcription factors, notably including Oct-4, Sox-2, and Nanog. However, in the pig, previous research indicates that Oct-4 protein and mRNA is not specifically localized to the inner cell mass (ICM) of the zona-intact (ZI) blastocyst. Levels of expression of Nanog mRNA, on the other hand, appear to be low in the ZI blastocyst, and protein has not been detected. Similarly, Sox-2 expression in the ZI blastocyst is relatively low and not specific to the ICM. In this study, we investigated the mRNA expression of Oct-4, Sox-2, and Nanog in D6/D7-derived ZI porcine in vivo-derived blastocysts compared with epiblasts mechanically isolated from hatched D10/D11 in vivo-derived blastocysts. We then investigated components involved in pathways important for regulating pluripotency, including JAK/STAT (i.e. gp130, LIFr), FGF (i.e. bFGF, FGFr1, FGFr2), and BMP (bmp4, smad4) signaling pathways and their downstream targets, stat3, c-myc, c-fos, by using RT-PCR. Sows were artificially inseminated, and embryos were flushed from uteri following slaughter. Single D6/D7 blastocysts (n = 3), single mechanically isolated D10/D11 epiblasts (n = 3), endometrium, and oviduct total RNA was isolated using the RNeasy Micro Kit (Qiagen, Valencia, CA, USA). Total RNA from the blastocysts and epiblasts was then amplified to form cDNA using the QuantiTect Whole Transcriptome kit (Qiagen). Positive control tissues (oviduct and endometrium) were reverse transcribed using the RevertAid First Strand cDNA synthesis kit (Fermentas, Burlington, Ontario, Canada). Primers were designed to span introns in highly homologous sequences to human mRNA. Primers were tested in both oviduct and endometrium tissue, and products were sequenced to confirm specificity. PCR was performed at 55°C for 35 cycles. Results indicate that D6/D7 blastocysts only expressed Oct-4 and not Nanog and Sox-2. In contrast, all 3 transcripts were expressed in D10/D11 epiblasts. The D10/D11 epiblasts also expressed LIFr, bFGF, FGFr1, FGFr2, bmp4, smad4, stat3, c-myc, and c-fos. The cytokine receptor gp130 was only weakly expressed in a single epiblast. In contrast, the earlier stage D6/D7 blastocysts failed to express these messengers with the exception of weak expression of gp130 in all 3 blastocysts, and only a single blastocyst expressed LIFr, smad4, c-myc, and c-fos. In conclusion, this study indicates that the ICM of the porcine D6/D7 ZI blastocyst has not developed pluripotency signaling as observed in mice and humans at this developmental stage. Furthermore, without expression of gp130, the JAK/STAT pathway is unlikely to play a role in regulating pluripotency in the epiblast. It is likely that the later stage epiblast may be more amenable for the derivation of porcine embryonic stem cells.

Regulation of stem cell differentiation by histone methyltransferases and demethylases

The generation of different cell types from stem cells containing identical genetic information and their organization into tissues and organs during development is a highly complex process that requires defined transcriptional programs. Maintenance of such programs is epigenetically regulated and the factors involved in these processes are often essential for development. The activities required for cell-fate decisions are frequently deregulated in human tumors, and the elucidation of the molecular mechanisms that regulate these processes is therefore important for understanding both developmental processes and tumorigenesis.

Theory of resonant acoustic transmission through subwavelength apertures

A complete landscape is presented of the acoustic transmission properties of subwavelength apertures (slits and holes). First, we study the emergence of Fabry-Perot resonances in single apertures. When these apertures are placed in a periodic fashion, a new type of transmission resonance appears in the spectrum. We demonstrate that this resonance stems from the excitation of an acoustic guided wave that runs along the plate, which hybridizes strongly with the Fabry-Perot resonances associated with waveguide modes in single apertures. A detailed discussion of the similarities and differences with the electromagnetic case is also given.

Risk for contralateral breast cancer among carriers of the CHEK2*1100delC mutation in the WECARE Study

The protein encoded by the CHEK2 gene is involved in cellular repair of DNA damage. The truncating mutation, CHEK2^*1100delC, seems to increase the risk for breast cancer. We investigated whether the CHEK2^*1100delC mutation carrier status increases the risk for asynchronous contralateral breast cancer (CBC) and whether it interacts with radiation therapy (RT) or chemotherapy in regard to CBC risk. The germline mutation frequency was assessed in 708 women with CBC and 1395 women with unilateral breast cancer (UBC) in the Women's Environment, Cancer and Radiation Epidemiology (WECARE) Study whose first primary breast cancer was diagnosed before age 55 years and during 1985–1999. Seven women with CBC (1.0%) and 10 women with UBC (0.7%) were CHEK2^*1100delC variant carriers (rate ratio (RR)=1.8, 95% confidence interval (CI)=0.6–5.4 for CBC vs UBC). Carriers who received RT for their first breast cancer, compared with non-carriers not treated with RT, had an RR of developing CBC of 2.6 (95% CI=0.8–8.7). We found no significant associations between the CHEK2^*1100delC mutation and CBC overall or among those treated with RT. However, the sampling variability was such that modest increases in risk could not be excluded. Nonetheless, because this is a rare mutation, it is unlikely to explain a major fraction of CBC in the population.

Induction of apoptosis of myeloid leukemia with CSC17.1, a unique monoclonal antibody targeting CD45RA

3030

Background: Blast crisis from myeloid leukemia is may be responsive to chemotherapy, but a majority of patients die from their disease. Relapse may be due to persistence of cancer stem cells (CSC). A monoclonal antibody (mAb) that targets myeloid blast cells including the CSC without targeting the hematopoietic stem cell (HSC: CD34+90+) may be of value. CSC phenotype of CML-BC (CD34+38+123+45RA+) and AML (CD34+38–90-) have been defined. Method: We developed a biologically based mAb platform with 2 important steps after generating the mAb library: i) mAb must not bind the HSC (SS; safety screen); and ii) must bind the target cells (RxS; therapeutic screen). HSC for the SS were from G-CSF mobilized blood; cells for RxS was patient specimens of CML-BC and AML. After screens, the target was indentified, in vitro and in vivo functional assays are performed. Results: 5 of 400 mAb passed the SS and RxS. CSC17.1, an IgG2b isotype binding a unique, linear, 12 amino acid sequence of CD45RA has been selected. CML (Kasumi4), AML (Kasumi3 and KG1a), ALL (MOLT3) and NHL (Pfeiffer) cel lines express high levels of CD45RA. Five of 5 CML-BC and 3 of 3 AML patient specimens express CD45RA in high levels. Kausmi4 and Pfeiffer cell lines and patient specimens of CML-BC and AML undergo apoptosis in a dose and time dependent manner after exposure to CSC17.1 (>80% apoptosis at 1ug/ml@8h). KG1a is refractory to apoptosis despite high levels of target on the cell surface (15% apoptosis at 1ug/ml@8h). Normal T,B and NK cells express high levels of CD45RA, but do not undergo apoptosis or activation when exposed to CSC17.1. CSC17.1 causes capping and patching, but not internalization of CD45RA in cell lines and CD8+ normal cells. Commercially available antibodies to CD45RA do not inhibit binding of CSC17.1 to CD45RA, do not cause apoptosis, do not cause patching and capping, but do undergo internalization. In vivo murine models with cell lines and patient specimens of CML-BC and AML are underway. Conclusions: 1) CSC17.1 binds a previously undefined epitope of CD45RA that causes apoptosis of selected hematopoietic tumor cell lines and patient specimens of CML-BC and AML; 2) apoptosis, is a unique function of CSC17.1 compared to other mAb against CD45RA; 3) CML-BC and AML CSC include the CD45RA antigen suggesting CSC17.1 will target these cells.

No significant financial relationships to disclose.