Slicing through silos: Development and evaluation of a hospital-based telehealth hepatitis C virus treatment program

BACKGROUND

There exist many barriers to hepatitis C virus (HCV) treatment for those with substance use disorder (SUD) or who lack access to routine medical care. A hospital-based telehealth program was developed to provide treatment opportunities for hospitalized patients living with HCV.

METHODS

This single site prospective cohort study conducted from July 2022 to March 2023 aimed to measure linkage to care with an HCV clinician and initiation of HCV treatment in hospitalized patients. Patients were assessed in-person by a social worker then seen via telehealth by a clinician who prescribed either glecaprevir/pibrentasvir or sofosbuvir/velpatasvir. Treatment was initiated with pharmacist assistance. The team conducted in-person and/or telephonic outreach during and after hospitalization. Cure was confirmed by sustained virologic response at 12 weeks (SVR12) post-treatment.

RESULTS

A total of 25 patients were enrolled and completed telehealth visits. All patients had a history of SUD and 18 (72 %) were unstably housed. Nineteen patients (76 %) initiated treatment, and 14 (56 %) successfully completed treatment. Twelve patients (48 %) completed post-treatment labs, including two who prematurely discontinued treatment. Eleven patients (44 %) achieved confirmed cure with SVR12.

CONCLUSION

A hospital-based, multidisciplinary telehealth program can be an innovative care model to successfully treat HCV in a difficult-to-treat patient populations.

Perspectives on digital testing services for sexually transmitted and blood-borne infections from Two-Spirit, gay, bisexual, transgender, and other queer Black, Indigenous, people of colour living in Ontario, Canada

OBJECTIVES

Increased sexually transmitted and blood-borne infections (STBBI) testing can reduce the burden of disease among Two-Spirit, gay, bisexual, transgender, and other queer Black, Indigenous, people of colour (2SGBTQ+ BIPOC). However, this population encounters barriers, such as discrimination, when accessing in-person STBBI testing services. Digital STBBI testing, such as self-testing/collection kits ordered online and digital requisitions, may address some of these barriers. Our aim was to understand acceptability of free digital STBBI testing among 2SGBTQ+ BIPOC living in Ontario, Canada.

DESIGN

We approached this analysis using Implementation Science and Critical Race Theory. We conducted interviews and focus groups with 21 2SGBTQ + BIPOC individuals from 2020-2021. Participants were asked about their perceptions of the benefits and drawbacks of digital STBBI testing, populations that would benefit from using these services, and recommendations for how these services may be implemented in Ontario. Interviews and focus groups were transcribed verbatim and analyzed using reflexive thematic analysis.

RESULTS

Six themes emerged. Digital STBBI testing services: (1) May reduce oppression experienced by 2SGBTQ + BIPOC when testing in-person; (2) Should address the unique needs that 2SGBTQ + BIPOC experience due to other intersecting identities they possess; (3) Should adapt their services to suit the varying cultural contexts and living circumstances of 2SGBTQ + BIPOC; (4) Should be accessible to 2SGBTQ + BIPOC who hold diverse or no documentation; (5) Should be offered in multiple languages; (6) May be inaccessible to those without Internet access or devices.

CONCLUSION

Digital STBBI testing is one strategy that may reduce discrimination experienced by 2SGBTQ + BIPOC when getting tested in-person. However, digital STBBI testing services may not address all the needs of 2SGBTQ + BIPOC. Racism and other forms of oppression embedded into in-person and digital testing services will need to be addressed to meet the needs of this diverse population.

Disruptions of sexually transmitted and blood borne infections testing services during the COVID-19 pandemic: accounts of service providers in Ontario, Canada

BACKGROUND

Since the onset of the COVID-19 pandemic in March 2020 in Canada, the availability of sexual health services including sexually transmitted and blood-borne infection (STBBI) testing has been negatively impacted in the province of Ontario due to their designation as "non-essential" health services. As a result, many individuals wanting to access sexual healthcare continued to have unmet sexual health needs throughout the pandemic. In response to this, sexual health service providers have adopted alternative models of testing, such as virtual interventions and self-sampling/testing. Our objective was to investigate service providers' experiences of disruptions to STBBI testing during the COVID-19 pandemic in Ontario, Canada, and their acceptability of alternative testing services.

METHODS

Between October 2020-February 2021, we conducted semi-structured virtual focus groups (3) and in-depth interviews (11) with a diverse group of sexual health service providers (n = 18) including frontline workers, public health workers, sexual health nurses, physicians, and sexual health educators across Ontario. As part of a larger community-based research study, data collection and analysis were led by three Peer Researchers and a Community Advisory Board was consulted throughout the research process. Transcripts were transcribed verbatim and analysed with NVivo software following grounded theory.

RESULTS

Service providers identified the reallocation of public health resources and staff toward COVID-19 management, and closures, reduced hours, and lower in-person capacities at sexual health clinics as the causes for a sharp decline in access to sexual health testing services. Virtual and self-sampling interventions for STBBI testing were adopted to increase service capacity while reducing risks of COVID-19 transmission. Participants suggested that alternative models of testing were more convenient, accessible, safe, comfortable, cost-effective, and less onerous compared to traditional clinic-based models, and that they helped fill the gaps in testing caused by the pandemic.

CONCLUSIONS

Acceptability of virtual and self-sampling interventions for STBBI testing was high among service providers, and their lived experiences of implementing such services demonstrated their feasibility in the context of Ontario. There is a need to approach sexual health services as an essential part of healthcare and to sustain sexual health services that meet the needs of diverse individuals.

Acceptability of an existing online sexually transmitted and blood-borne infection testing model among gay, bisexual and other men who have sex with men in Ontario, Canada

Objectives

Gay, bisexual and other men who have sex with men (GBM) are disproportionately affected by sexually transmitted and blood-borne infections (STBBI) due to stigma and other factors such as structural barriers, which delay STBBI testing in this population. Understanding acceptability of online testing is useful in expanding access in this population, thus we examined barriers to clinic-based testing, acceptability of a potential online testing model, and factors associated with acceptability among GBM living in Ontario.

Methods

Sex Now 2019 was a community-based, online, bilingual survey of GBM aged ≥15. Prevalence ratios (PR) and 95% confidence intervals (95%CI) were calculated using modified Poisson regression with robust variances. Multivariable modelling was conducted using the Hosmer-Lemeshow-Sturdivant approach.

Results

Among 1369 participants, many delayed STBBI testing due to being too busy (31%) or inconvenient clinic hours (29%). Acceptability for online testing was high (80%), with saving time (67%) as the most common benefit, and privacy concerns the most common drawback (38%). Statistically significant predictors of acceptability for online testing were younger age (PR  =  0.993; 95%CI: 0.991-0.996); a greater number of different sexual behaviours associated with STBBI transmission (PR  =  1.031; 95%CI: 1.018-1.044); identifying as an Indigenous immigrant (PR  =  1.427; 95%CI: 1.276-1.596) or immigrant of colour (PR  = 1.158; 95%CI: 1.086-1.235) compared with white non-immigrants; and currently using HIV pre-exposure prophylaxis (PrEP) compared to not currently using PrEP (PR  =  0.894; 95%CI: 0.828-0.965).

Conclusions

Acceptability of online testing was high among GBM in Ontario. Implementing online STBBI testing may expand access for certain subpopulations of GBM facing barriers to current in-person testing.

Cisnormativity as a structural barrier to STI testing for trans masculine, two-spirit, and non-binary people who are gay, bisexual, or have sex with men

Trans masculine, two-spirit, and non-binary people who are gay, bisexual or otherwise have sex with men (TGBM) are under-tested for sexually transmitted infections (STI) and may face complex, intersectional barriers that prevent them from accessing STI testing. As part of a study on gay, bisexual and other men who have sex with men's (GBM) experiences of current STI testing systems in Ontario, Canada, this paper reports on the findings from TGBM participants' experiences with in-person STI testing in a range of venues (i.e. Family doctors, walk-in clinics, and community-based organizations) to explore testing barriers specific to TGBM. Using a community-based research approach, between June 2020 and December 2021 peer researchers who identified as GBM conducted focus groups and interviews with 38 cis and trans GBM, 13 of whom identified as TGBM. Data were analyzed following grounded theory. When questioned about past experiences with testing, TGBM participants reported several barriers to STI testing within current testing models in Ontario due to cisnormativity and heteronormativity. Cisnormativity is the assumption that everyone identifies as the gender they were assigned at birth, and those who do not are considered "abnormal", while heteronormativity is when it is assumed that everyone is heterosexual. From our research we identified three overarching themes concerning testing barriers among TGBM participants: (1) non-inclusive clinic environments, (2) lack of provider knowledge and competency, and (3) legal documentation. Inherent cis and heteronormativity in healthcare institutions appear to be factors shaping the historical under-testing for STI in the TGBM population. These findings suggest the relevance of implementing trans-specific clinical practices that reduce the stigma and barriers faced by TGBM in STI testing contexts, including: hosting all-gender testing hours, opening more LGBTQ+ clinics, offering training in transgender health to testing providers, and conducting a review of how gender markers on health documents can be more inclusive of trans, two-spirit, and non-binary communities.

Comparison of image quality of abdominopelvic CT in paediatric patients: low osmolar contrast media versus less iodine-containing iso-osmolar contrast media at different peak kilovoltages

AIM

To evaluate the effect of iso-osmolar contrast media (IOCM) at different tube voltages on image quality for abdominal computed tomography (CT) in paediatric patients.

MATERIALS AND METHODS

The low osmolar contrast media (LOCM) group and IOCM group consisted of 101 and 102 CT examinations, respectively, in patients <18 years old. Images were reviewed retrospectively. Objective measurement of the contrast enhancement and noise were analysed and contrast-to-noise ratios (CNRs) of the abdominal aorta, portal vein, and liver were calculated. Four radiologists participated in subjective analysis using a four-point scale system to evaluate degrees of contrast enhancement, image noise, beam-hardening artefact, and overall image quality. Reader performance for correctly differentiating the two kinds of contrast media was evaluated.

RESULTS

Regarding the objective measurement, contrast enhancement was significantly higher in the LOCM group (p<0.05). In subjective analysis, only CT using 120 kVp showed significantly stronger enhancement in the LOCM group (p=0.002), and sensitivity to differentiate the IOCM was 80.6%. Overall sensitivity and specificity for correctly differentiating IOCM were 57.1%, and 56.9%, respectively.

CONCLUSION

The application of IOCM was found to be feasible for performing paediatric abdominopelvic CT with a low tube voltage protocol. Although objective measurements of contrast enhancement were significantly lower in the IOCM group, subjective contrast enhancement and image quality assessments were not statistically different between groups.

Preoperative N stage evaluation in advanced gastric cancer patients using multidetector CT: can the sum of the diameters of metastatic LNs be used for N stage evaluation?

AIM

To compare the diagnostic performance of total counts of metastatic lymph nodes (LN-sum) and conventional multidetector (MD) computed tomography (CT) staging in the nodal evaluation of advanced gastric cancer (AGC) patients.

MATERIALS AND METHODS

In total, 127 consecutive patients who underwent preoperative MDCT and gastrectomy for AGC were identified. Metastatic LNs on MDCT were defined as LNs with a short axis ≥8 mm, marked or heterogeneous enhancement, and morphological features (central necrosis, round shape, clustering). The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of the N-stage using LN-sum and conventional MDCT staging were generated and compared. In addition, metastatic LN counts between the MDCT and the histopathological examinations and correlation between LN-sum and histopathological nodal status were analysed.

RESULTS

The total counts of metastatic LNs on MDCT was significantly smaller than those detected in histopathological assessments (p<0.0001). LN-sum showed significant correlation with the pathological N stage and the number of metastatic LNs (rho=0.69, 0.73, p<0.0001). The areas under the receiver operating characteristic curve were 0.896, and 0.835, for N stage ≥N2 and N3, with cut-off values of 12.5 and 23.5 mm, respectively. LN-sum provided better diagnostic performance than conventional MDCT staging for discriminating N0-2 versus N3; sensitivity, accuracy, PPV and NPV of LN-sum were significantly higher (80.4 versus 52.2%, 81.1 versus 68.5%, 71.2 versus 57.1%, and 88 versus 74.1%).

CONCLUSION

LN-sum may be sufficiently useful in assessing the N3 stage of AGC and may help to plan appropriate therapy for AGC patients.

Stimuli-responsive magneto-/electro-chromatic color-tunable hydrophobic surface modified Fe3O4@SiO2 core–shell nanoparticles for reflective display approaches

Magneto-/electro-chromatic reflective color tunability is confirmed using hydrophobic surface modified magnetite nanoparticles. The optical reflective color spectra and color gamut demonstrate the promising applications in reflective displays.

Therapeutic targeting of epigenetic components in amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS) is an adult-onset motor neuron disease characterized by degeneration of motor neuron and glial activation followed by the progressive muscle loss and paralysis. Numerous distinct therapeutic interventions have been examined but currently ALS does not have a cure or an efficacious treatment for the disorder. Glutamate- induced excitotoxicity, inflammation, mitochondrial dysfunction, oxidative stress, protein aggregation, transcription deregulation, and epigenetic modifications are associated with the pathogenesis of ALS and known to be therapeutic targets in ALS. In this review, we discuss translational pharmacological studies targeting epigenetic components to ameliorate ALS. Understanding of the epigenetic mechanisms will provide novel insights that will further identify potential biological markers and therapeutic approaches for treating ALS. A combination of treatments that modulate epigenetic components and multiple targets may prove to be the most effective therapy for ALS.

A Large National Cohort Study of the Association between Bisphosphonates and Osteonecrosis of the Jaw in Patients with Osteoporosis

The purpose of this study was to examine the association between bisphosphonate exposure and osteonecrosis of the jaw (ONJ) in Korean patients with osteoporosis. A nested case-control study was performed using the claims database during 2002 to 2010 provided by the National Health Insurance Service. We identified a cohort of individuals with diagnosis of osteoporosis during 2002 to 2010. Cases and controls were identified during 2004 to 2010, and the date of potential cases of ONJ was defined as the index date. Bisphosphonate exposure was evaluated during 2 y prior to the index date. The association between bisphosphonate exposure and ONJ was tested by performing a conditional logistic regression analysis for matched data, and odds ratios (ORs) with 95% confidence intervals (CIs) were presented. Subjects were classified as nonuser, recent user, past user, or continuous user, depending on the prescription of bisphosphonates in 2 periods (1 to 2 y and 0 to 1 y prior to the index date). Continuous users were defined as patients who were exposed to bisphosphonate in both periods. We also examined the impact of bisphosphonate medication compliance by measuring the cumulative duration of exposure (CDE) on the risk of ONJ. A total of 212 cases with ONJ and 2,120 controls matched by sex, age, income level, and insurance type were identified among 109,787 patients with osteoporosis out of 1,025,340 enrollees in the sample cohort. The odds of having ONJ after adjusting for patient comorbidities significantly increased in continuous users of bisphosphonates (OR, 3.9; 95% CI, 2.4 to 6.2) compared to nonusers. Increased odds of ONJ were observed as CDE increased. The adjusted OR in patients with 1.5 y < CDE ≤ 2 y prior to the index date was 7.8 (95% CI, 4.0 to 15.5) versus nonusers. Our study results support significantly increased occurrences of potential ONJ in patients with osteoporosis who were exposed to bisphosphonates compared to those without exposure.

Why do wild bonobos not use tools like chimpanzees do?

One of the most conspicuous behavioural differences among great apes is the paucity of tool use among wild bonobos (Pan paniscus) in comparison to chimpanzees (Pan troglodytes) who are one of the most prolific and skilled tool users in the animal kingdom. This is in spite of the fact that bonobo tool use repertories are as large and diverse as chimpanzees’ in captive settings. In this study, we compared tool using behaviours and potential drivers of these behaviours in the Wamba bonobo population located in central Democratic Republic of Congo with the Goualougo chimpanzee population of northern Republic of Congo. The tool use repertoire of wild bonobos was comprised of only 13 behaviours, compared to 42 for chimpanzees. However, the number of tool behaviours observed in each study site was similar between bonobos and chimpanzees, and many types of tool use for social, self-grooming/stimulation, and comfort/protection functions were commonly used by both species. A marked difference is that 25 of 42 tool behaviours exhibited by chimpanzees are performed for feeding, in contrast to a single report of bonobos using a leaf sponge to drink water. We examined whether the differences in tool use repertoires can be explained by the necessity, opportunity, relative profitability, or invention hypotheses. We found that habitat composition and fluctuation of fruit production at these two sites were similar, particularly when compared with variation observed between sites within each species. Thus it was unlikely that the necessity hypothesis explains the lack of tool use for feeding in bonobos. Though further study at Wamba is needed, we did not identify any obvious differences in prey availability that would indicate differences in tool using opportunities between the sites. This study could not test the relative profitability hypothesis, and further research is needed on whether tool use is the most efficient means of calorie or protein intake for wild apes. Bonobos at Wamba formed much larger and stable parties than chimpanzees at Goualougo, which was contrary to the prediction by the invention hypothesis. Another explanation is that differences in tool use behaviour between bonobos and chimpanzees might not be explained by the current ecological or social conditions, but rather by circumstances during the Pleistocene Epoch. The observed species differences might also reflect divergent behavioural predispositions, rather than actual differences in cognitive abilities.

CR6-interacting factor 1 is a key regulator in Aβ-induced mitochondrial disruption and pathogenesis of Alzheimer's disease

Mitochondrial dysfunction, often characterized by massive fission and other morphological abnormalities, is a well-known risk factor for Alzheimer's disease (AD). One causative mechanism underlying AD-associated mitochondrial dysfunction is thought to be amyloid-β (Aβ), yet the pathways between Aβ and mitochondrial dysfunction remain elusive. In this study, we report that CR6-interacting factor 1 (Crif1), a mitochondrial inner membrane protein, is a key player in Aβ-induced mitochondrial dysfunction. Specifically, we found that Crif1 levels were downregulated in the pathological regions of Tg6799 mice brains, wherein overexpressed Aβ undergoes self-aggregation. Downregulation of Crif1 was similarly observed in human AD brains as well as in SH-SY5Y cells treated with Aβ. In addition, knockdown of Crif1, using RNA interference, induced mitochondrial dysfunction with phenotypes similar to those observed in Aβ-treated cells. Conversely, Crif1 overexpression prevented Aβ-induced mitochondrial dysfunction and cell death. Finally, we show that Aβ-induced downregulation of Crif1 is mediated by enhanced reactive oxygen species (ROS) and ROS-dependent sumoylation of the transcription factor specificity protein 1 (Sp1). These results identify the ROS-Sp1-Crif1 pathway to be a new mechanism underlying Aβ-induced mitochondrial dysfunction and suggest that ROS-mediated downregulation of Crif1 is a crucial event in AD pathology. We propose that Crif1 may serve as a novel therapeutic target in the treatment of AD.

Direct determination of exchange parameters in Cs2CuBr4 and Cs2CuCl4: high-field electron-spin-resonance studies

Spin-1/2 Heisenberg antiferromagnets Cs2CuCl4 and Cs2CuBr4 with distorted triangular-lattice structures are studied by means of electron spin resonance spectroscopy in magnetic fields up to the saturation field and above. In the magnetically saturated phase, quantum fluctuations are fully suppressed, and the spin dynamics is defined by ordinary magnons. This allows us to accurately describe the magnetic excitation spectra in both materials and, using the harmonic spin-wave theory, to determine their exchange parameters. The viability of the proposed method was proven by applying it to Cs2CuCl4, yielding J/kB=4.7(2)  K, J'/kB=1.42(7)  K, [J'/J≃0.30] and revealing good agreement with inelastic neutron-scattering results. For the isostructural Cs2CuBr4, we obtain J/kB=14.9(7)  K, J'/kB=6.1(3)  K, [J'/J≃0.41], providing exact and conclusive information on the exchange couplings in this frustrated spin system.

Cooperative role of RanBP9 and P73 in mitochondria-mediated apoptosis

Mitochondrial dysfunction and synaptic damage are critical early features of Alzheimer's disease (AD) associated with amyloid β (Aβ) and τ. We previously reported that the scaffolding protein RanBP9, which is overall increased in AD, simultaneously promotes Aβ generation and focal adhesion disruption by accelerating the endocytosis of APP and β1-integrin, respectively. Moreover, RanBP9 induces neurodegeneration in vitro and in vivo and mediates Aβ-induced neurotoxicity. However, little is known regarding the mechanisms underlying such neurotoxic processes. Here, we show that RanBP9 induces the loss of mitochondrial membrane potential and increase in mitochondrial superoxides associated with decrease in Bcl-2, increase in Bax protein and oligomerization, fragmentation of mitochondria, and cytochrome c release. RanBP9-induced neurotoxic changes are significantly prevented by the mitochondrial fission inhibitor Mdivi-1 and by classical inhibitors of the mitochondrial apoptosis, XIAP, Bcl-2, and Bcl-xl. RanBP9 physically interacts with the tumor suppressor p73 and increases endogenous p73α levels at both transcriptional and post-translational levels;moreover, the knockdown of endogenous p73 by siRNA effectively blocks RanBP9 and Aβ1-42-induced mitochondria-mediated cell death. Conversely, siRNA knockdown of endogenous RanBP9 also suppresses p73-induced apoptosis, suggesting that RanBP9 and p73 have cooperative roles in inducing cell death. Taken together, these finding implicate the RanBP9/p73 complex in mitochondria-mediated apoptosis in addition to its role in enhancing Aβ generation.

Critical role of presenilin-dependent γ-secretase activity in DNA damage-induced promyelocytic leukemia protein expression and apoptosis

Promyelocytic leukemia (PML) is a major component of macromolecular multiprotein complexes called PML nuclear-bodies (PML-NBs). These PML-NBs recruit numerous proteins including CBP, p53 and HIPK2 in response to DNA damage, senescence and apoptosis. In this study, we investigated the effect of presenilin (PS), the main component of the γ-secretase complex, in PML/p53 expression and downstream consequences during DNA damage-induced cell death using camptothecin (CPT). We found that the loss of PS in PS knockout (KO) MEFs (mouse embryonic fibroblasts) results in severely blunted PML expression and attenuated cell death upon CPT exposure, a phenotype that is fully reversed by re-expression of PS1 in PS KO cells and recapitulated by γ-secretase inhibitors in hPS1 MEFs. Interestingly, the γ-secretase cleavage product, APP intracellular domain (AICD), together with Fe65-induced PML expression at the protein and transcriptional levels in PS KO cells. PML and p53 reciprocally positively regulated each other during CPT-induced DNA damage, both of which were dependent on PS. Finally, elevated levels of PML-NB, PML protein and PML mRNA were detected in the brain tissues from Alzheimer's disease (AD) patients, where γ-secretase activity is essential for pathogenesis. Our data provide for the first time, a critical role of the PS/AICD-PML/p53 pathway in DNA damage-induced apoptosis, and implicate this pathway in AD pathogenesis.

Magnesium-doped zinc oxide electrochemically grown on fluorine-doped tin oxide substrate

Nanostructures of magnesium (Mg) doped Zinc oxide (ZnO) were successfully deposited on conducting fluorine-doped tin oxide (FTO) coated glass plates by cathodic electrochemical deposition method at different potentials and temperature conditions. The deposited samples were characterized by XRD and SEM techniques to confirm their structures, morphologies and optical properties. These measurements show that Mg doped ZnO has a wurtzite structure and that the strongest intensity of the (002) peak is found at 60 degrees C and -1.0 V. Tunable transmittance of Mg doped ZnO has a band gap energy from 3.45 eV to 3.82 eV, which is the direct evidence of doping.

Ethanol-induced DNA damage and the expression of repair-related molecules in human gastric carcinoma AGS cells with use of an acid pump antagonist and proton pump inhibitor

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Background: Proton pump inhibitor (PPI) inhibits gastric acid secretion by strongly suppressing H + / K +- ATPase of parietal cells and is a major drug for peptic ulcers and gastroesophageal reflux. Recently it was reported that PPI has antioxidant and anti- inflammatory effects as well as a powerful acid inhibitory effect. To analyze the DNA repair capacity from the antioxidant effect of acid pump antagonist (Revanex-RN) and proton pump inhibitor (Omeprazole-OP), this study examined ethanol-induced DNA damage and the expression of repair related molecules in human gastric cancer AGS cells pretreated with an acid pump antagonist and a proton pump inhibitor.

Methods: AGS, a human gastric cancer cell line was obtained from ATCC, was treated with ethanol (0, 2, 4, 6, 8, 10%) during 1hr. MTT and Comet assay were performed to evaluate ethanol-induced DNA damage. The optimum concentration of ethanol which caused DNA damage was established. And AGS cells were cultured in proper concentration of RN or OP overnight. Then, these cells were treated with 5% ethanol during 1hr. DNA damage and recovery were represented the value of Olive tail moment in comet assay. Western blot was also performed to detect expression of DNA polymerase beta, APE/ref-1, PCNA, and GADD45.

Results: The DNA damage of AGS cell depended upon ethanol concentration distinctly. Damaged cells showed up recovered tendency in the group treated with low dose RN or OP. In addition, DNA repair enzymes including DNA polymerase beta and APE/ref-1 which were associated with mechanism of base excision repair (BER) were increased. A relevant protein such as GADD45 was also increased significantly.

Conclusions: PPI has capacity to recover damaged DNA, which is associated with increased expression of GADD45 directly. Therefore, PPI offers cancer prevention by reducing the level of DNA damage in the gastric mucosa. GADD45 is also likely to suggest that it could be used a major factor on the injury mechanism and an indicator of mucosal damage in stomach. Moreover, RN, an acid pump antagonist is expected to have the higher safety compared to the existing PPIs and considered to be equal to PPIs in terms of anti-cancer effect.

No significant financial relationships to disclose.

Novel multiphoton microscopy probe and feasibility study for colon cancer: Probe on trace elements–related antioxidant

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Background: Multiphoton microscopy (MPM) has gained increasing popularity during the past few years because of the distinct advantages over single-photon microscopy, which includes increased penetration depth and low out-of-focus photodamage. However, there had been no report on multiphoton probes for malignancy. Previous studies reported that Zn and Cu ions which are co-factor of antioxidants such as superoxide dismutase (SOD), altered in malignancy tissue. The aim of this study was to evaluate application of the multiphoton (MP) probe of Zn and Cu for colon cancer tissues.

Methods: We monitored the Zn/Cu ions in the colon cancer cell lines with multiphoton probe Microscopy. The multiphoton probe AZn2+ (C38H38N6O3) and ACu+ (C34H47N3O3S4), we developed and obtained the patent on it, were stained in live cancer cell lines. The tissues of colon cancer, adenoma and normal mucosa were obtained by biopsy during colonoscopy. Then the tissues were stained with 20μM of the MP probes for Zn/Cu ions. The distribution and concentration of zinc and copper ions were monitored by MPM by following the change in MPEF along the depth of tissue.

Results: The majority of Zn2+ and Cu+ ions distributed in cytosole. The average multi-photon excited fluorescence (MPEF) intensities due to Cu, Zn, and Cu/Zn ratio were remarkably different between the normal mucosa and adenoma/adenocarcinoma tissues. The Zn2+ content was significantly lower and the Cu2+ content was significantly higher to result in a much lower the Zn/Cu ratio in adenoma/adenocarcinoma than in normal mucosa tissues.

Conclusions: We have obtained multiphoton microscopy images of normal and cancer cell lines as well as mucosa and adenoma/adenocarcinoma tissues labeled with newly developed MP probes AZn1 and ACu1.

No significant financial relationships to disclose.