Corrigendum: Eastern Canadian Gastrointestinal Cancer Consensus Conference 2014.

[This corrects the article DOI: 10.3747/co.22.2603.].

Eastern Canadian Gastrointestinal Cancer Consensus Conference 2014.

The annual Eastern Canadian Colorectal Cancer Consensus Conference was held in Montreal, Quebec, 23-25 October 2014. Expert radiation, medical, and surgical oncologists and pathologists involved in the management of patients with gastrointestinal malignancies participated in presentations and discussions resulting in consensus statements on such hot topics as management of neuroendocrine tumours, advanced and metastatic pancreatic cancer, and metastatic colorectal cancer.

ABO-incompatible heart transplants.

A month-old baby girl with blood type O positive received a donor heart organ from a donor with blood type B. This was the first institutional ABO-incompatible heart transplant. Infants listed for transplantation may be considered for an ABO-incompatible heart transplant based on their antibody levels and age. The United Network of Organ Sharing (UNOS) protocol is infants under 24 months with titers less than or equal to 1:4.(1) This recipient's anti-A and anti-B antibodies were monitored with titer assays to determine their levels; antibody levels less than 1:4 are acceptable pre-transplant in order to proceed with donor and transplant arrangements.1 Immediately prior to initiating cardiopulmonary bypass (CPB), a complete whole body exchange transfusion of at least two-times the patient's circulating blood volume was performed with packed red blood cells (pRBC), fresh frozen plasma (FFP) and 25% albumin. Titer assays were sent two minutes after initiation of full CPB and then hourly until the cross-clamp was removed. Institutionally, reperfusion of the donor heart is not restored until the antibody level from the titer assay is known and reported as less than 1:4; failing to achieve an immulogically tolerant recipient will provide conditions for hyperacute rejection. The blood collected during the transfusion exchange was immediately processed through a cell saver so the pRBC's could be re-infused to the patient during CPB, as necessary. The remainder of the transplant was performed in the same fashion as an ABO-compatible heart transplant. The patient has shown no signs of rejection following transplantation.

Anomalies in the inflammatory response in endometriosis and possible consequences: a review.

Defined by the presence of endometrial-like cells outside the uterus, endometriosis is one of the most diagnosed gynecological disorders, affecting 5 to 10 % of reproductive age women, but the true incidence is unknown. Endometriosis is a major cause of pelvic pain, dysmenorrhea, dyspareunia, infertility and menstrual irregularities, but there is no clear correlation between the symptoms and the extent of the disease. Despite decades of intensive investigations, little is known about the pathogenesis of endometriosis. The disease is often associated with chronic pelvic inflammation. Abnormal levels of immune cells such macrophages, dendritic and natural killer cells were found in the peritoneal cavity of patients. However these cells seem to be unable to detect and eliminate ectopic endometrial cells. Several studies showed that peritoneal immune cells are dysfunctional and may rather contribute to endometriosis development. A review of relevant clinical and scientific studies was carried out. This review sheds light on cellular and immunological pro-inflammatory changes which were observed in patients with endometriosis, their impact on angiogenesis, apoptosis, extracellular matrix remodeling and hormonal production and consequences on fertility.

Incorporating high fidelity simulation into perfusion education.

The new Perfusion Simulation Center at the Medical University of South Carolina provides a new level of high fidelity simulation training for perfusion students. A key component is the Orpheus Perfusion Simulator which is a computer-driven simulator integrated with the mechanical connections of the heart-lung machine to allow for real time operative procedures and perfusion incidents. Due to the ability to consistently reproduce cardiac surgical scenarios, it is possible to develop both basic perfusion skills as well as advanced emergency skills more effectively than with animal models. The purpose of this paper is to provide details about advanced simulation for perfusionists and to illustrate how simulation can be used to promote the assets of good communication, team work, and surgical awareness. Two sets of four cardiac surgical scenarios were recorded in the perfusion simulation operating room. Scenario team member roles included a cardiac surgeon, an anesthesiologist, a perfusionist and an operating room nurse. The scripted surgical scenarios were viewed by a focus group of students charged with identifying key personality traits of different members of the operating team and to characterize them using a list of descriptive words adapted from the Medical University of South Carolina's Peer Review Tool. In the first set of scenarios, initial scores were negative, with irresponsibility, impatience, and carelessness listed as the top behavioral characteristics leading to human error. In the second set of scenarios, logical, clear-thinking, and attentive were the most common personality traits observed of the effective team members. Simulation has become an invaluable tool for perfusion education and the goal of improving patient safety during cardiopulmonary bypass. The opportunities for advanced training in the perfusion simulation environment will certainly expand in the future.

Eastern Canadian Colorectal Cancer Consensus Conference: setting the limits of resectable disease.

The annual Eastern Canadian Colorectal Cancer Consensus Conference was held in Montreal, Quebec, October 22-24, 2009. Health care professionals involved in the care of patients with colorectal cancer participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management colorectal cancer, such as the management of hepatic and pulmonary metastases, the role of monoclonal antibodies to the epidermal growth factor receptor, and the benefits and safety of chemotherapy in elderly patients. The management of gastrointestinal neuroendocrine tumours and gastric cancer are also discussed.

Tattoo darkening and nonresponse after laser treatment: a possible role for titanium dioxide.

OBJECTIVE: To examine relationships between chemical composition, biopsy findings, and clinical outcome in laser-treated tattoos. DESIGN: Observational nonblinded retrospective study. SETTINGS: University-based dermatology clinic and private practice. PARTICIPANTS: Twenty patients who underwent biopsy of laser-treated tattoos. MAIN OUTCOME MEASURES: Biopsy specimens were analyzed after laser treatment, and the depths of changed particles were recorded. Ultrastructure of the changed particles was examined by electron microscopy. Presence of inorganic chemicals was determined by x-ray diffraction. Correlation between x-ray diffraction, microscopy, and clinical response was attempted. RESULTS: Of the 20 tattoos, 7 lightened, 9 failed to change, and 4 darkened after laser treatment. There was a significant association between presence of titanium dioxide and poor response to laser therapy. Microscopic studies showed variable changes in the ink particles, but there was a trend toward residual deep green pigment in the resistant tattoos. Also, round dark stippling was observed superficially in the darkened specimens. CONCLUSIONS: Titanium is overrepresented in tattoos that respond poorly to laser treatment. Further studies are necessary to show whether this metal is the primary cause of this poor response.

Verteporfin photodynamic therapy retreatment of normal retina and choroid in the cynomolgus monkey.

OBJECTIVE: This study evaluated the effect of repeated photodynamic therapy (PDT) applications on normal primate retina and choroid using an intravenous infusion of liposomal benzoporphyrin derivative (verteporfin). DESIGN: This was an experimental study in a primate model. ANIMALS/CONTROLS: Six cynomolgus monkeys were used as experimental subjects and one monkey was used as a control subject. INTERVENTION: Three consecutive PDT treatments at 2-week intervals were applied over the center of the fovea or the optic nerve of each eye. Verteporfin was delivered by intravenous infusion at a dose of 6 mg/m2, 12 mg/m2, or 18 mg/m2. Laser irradiation was then applied using a diode laser (689 nm) with light doses and spot sizes kept constant. MAIN OUTCOME MEASURES: Findings were documented by fundus photography, fluorescein angiography, and light and electron microscopy. RESULTS: A cumulative dose response was seen angiographically and histologically with more severe damage to the retina and choroid noted at higher dye doses. Photodynamic therapy applied to the macula using the 6-mg/m2 verteporfin dose showed recovery of choriocapillaris, with mild retinal pigment epithelium and outer photoreceptor damage at 6 weeks. At this dose, the optic nerve showed few focal sites of axon atrophy and capillary loss. Treatments over the macula using the 12-mg/m2 and 18-mg/m2 doses led to chronic absence of choriocapillaris and photoreceptors at 6 weeks. One of two optic nerves became atrophic after PDT applications using dye doses of 12 mg/m2, and both optic nerves became atrophic in the 18-mg/m2 dye dose group. CONCLUSION: Limited damage to the retina, choroid, and optic nerve was present in primates treated with multiple PDT sessions using 6 mg/m2 verteporfin with light doses and the timing of irradiation kept constant. However, PDT using higher dye doses of 12 mg/m2 and 18 mg/m2 led to significant chronic damage to the normal retina, choroid, and optic nerve.

Effects of photodynamic therapy using verteporfin on experimental choroidal neovascularization and normal retina and choroid up to 7 weeks after treatment.

PURPOSE: To study the long-term effects of photodynamic therapy (PDT), using liposomal benzoporphyrin derivative (BPD) or Verteporfin, on experimental choroidal neovascularization (CNV) and on normal retina and choroid (with no CNV) in the cynomolgus monkey eye. METHODS: Photodynamic therapy was performed in 8 cynomolgus monkey eyes with experimental CNV induced by laser injury. The effect of PDT on normal retina and choroid (with no CNV) was studied in 9 monkey eyes. Liposomal BPD was administered intravenously (0.375 mg/kg) either as a bolus, as a slow infusion over 32 minutes, or as a fast infusion over 10 minutes. Photodynamic therapy was performed using light at a wavelength of 689 or 692 nm, with an irradiance of 600 mW/cm2 and fluence of 150 J/cm2. Follow-up studies, including fundus photography and FA, were performed at 24 hours after PDT and then weekly. Indocyanine green and BPD angiography were performed in selected cases. Tissues were examined with light and electron microscopy at the end of follow-up. RESULTS: Twenty-three of the 32 areas of CNV treated with PDT showed absence of angiographic leakage at 24 hours. Twenty-eight areas of CNV were followed for 4 weeks; 22 of 28 showed absence of angiographic leakage at 2 weeks; and 20 of 28 at 4 weeks of follow-up. Forty spots on the normal retina and choroid were treated with PDT and were followed for 4 to 7 weeks. These spots showed pigment-laden cells in the outer retina, variably pigmented retinal pigment epithelium (RPE) in the treated area, intact neurosensory retina, and reperfusion of the choriocapillaris. CONCLUSIONS: Photodynamic therapy leads to absence of angiographic leakage for at least 4 weeks in experimental CNV in the monkey model. In the normal monkey eye the RPE and choriocapillaris show generalized recovery with preservation of the neurosensory retina 7 weeks after PDT.

Identification of constitutive and ras-inducible phosphorylation sites of KSR: implications for 14-3-3 binding, mitogen-activated protein kinase binding, and KSR overexpression.

Genetic and biochemical studies have identified kinase suppressor of Ras (KSR) to be a conserved component of Ras-dependent signaling pathways. To better understand the role of KSR in signal transduction, we have initiated studies investigating the effect of phosphorylation and protein interactions on KSR function. Here, we report the identification of five in vivo phosphorylation sites of KSR. In serum-starved cells, KSR contains two constitutive sites of phosphorylation (Ser297 and Ser392), which mediate the binding of KSR to the 14-3-3 family of proteins. In the presence of activated Ras, KSR contains three additional sites of phosphorylation (Thr260, Thr274, and Ser443), all of which match the consensus motif (Px[S/T]P) for phosphorylation by mitogen-activated protein kinase (MAPK). Further, we find that treatment of cells with the MEK inhibitor PD98059 blocks phosphorylation of the Ras-inducible sites and that activated MAPK associates with KSR in a Ras-dependent manner. Together, these findings indicate that KSR is an in vivo substrate of MAPK. Mutation of the identified phosphorylation sites did not alter the ability of KSR to facilitate Ras signaling in Xenopus oocytes, suggesting that phosphorylation at these sites may serve other functional roles, such as regulating catalytic activity. Interestingly, during the course of this study, we found that the biological effect of KSR varied dramatically with the level of KSR protein expressed. In Xenopus oocytes, KSR functioned as a positive regulator of Ras signaling when expressed at low levels, whereas at high levels of expression, KSR blocked Ras-dependent signal transduction. Likewise, overexpression of Drosophila KSR blocked R7 photoreceptor formation in the Drosophila eye. Therefore, the biological function of KSR as a positive effector of Ras-dependent signaling appears to be dependent on maintaining KSR protein expression at low or near-physiological levels.

Comparison of responses of tattoos to picosecond and nanosecond Q-switched neodymium: YAG lasers.

OBJECTIVE: To test the hypothesis that picosecond laser pulses are more effective than nanosecond domain pulses in clearing of tattoos. DESIGN: Intratattoo comparison trial of 2 laser treatment modalities. SETTING: A large interdisciplinary biomedical laser laboratory on the campus of a tertiary medical center. PATIENTS: Consecutive patients with black tattoos were enrolled; all 16 patients completed the study. INTERVENTION: We treated designated parts of the same tattoo with 35-picosecond and 10-nanosecond pulses from 2 neodymium:YAG lasers. Patients received a total of 4 treatments at 4-week intervals. All laser pulse parameters were held constant except pulse duration. Radiation exposure was 0.65 J/cm2 at the skin surface. Biopsies were performed for routine microscopic and electron microscopic analysis at the initial treatment session and 4 weeks after the final treatment in 8 consenting patients. Also, ink samples were irradiated in vitro. MAIN OUTCOME MEASURES: In vivo, on the completion of treatment, a panel of dermatologists not associated with the study (and blinded to the treatment type) evaluated photographs to assess tattoo lightening. Formalin-fixed specimens were examined for qualitative epidermal and dermal changes as well as depth of pigment alteration. Electron micrographs were examined for particle electron density and size changes (in vivo and in vitro). The gross in vitro optical density changes were measured. RESULTS: In 12 of 16 tattoos, there was significant lightening in the picosecond-treated areas compared with those treated with nanosecond pulses. Mean depth of pigment alteration was greater for picosecond pulses, but the difference was not significant. In vivo biopsy specimens showed similar electron-lucent changes for both pulse durations. In vitro results were similar for both pulse durations, showing increases in particle sizes and decreased electron density as well as gross ink lightening. CONCLUSIONS: Picosecond pulses are more efficient than nanosecond pulses in clearing black tattoos. Black tattoos clear principally by laser-induced changes in the intrinsic optical properties of the ink.

KSR stimulates Raf-1 activity in a kinase-independent manner.

Kinase suppressor of Ras (KSR) is an evolutionarily conserved component of Ras-dependent signaling pathways. Here, we find that murine KSR (mKSR1) translocates from the cytoplasm to the plasma membrane in the presence of activated Ras. At the membrane, mKSR1 modulates Ras signaling by enhancing Raf-1 activity in a kinase-independent manner. The activation of Raf-1 is mediated by the mKSR1 cysteine-rich CA3 domain and involves a detergent labile cofactor that is not ceramide. These findings reveal another point of regulation for Ras-mediated signal transduction and further define a noncatalytic role for mKSR1 in the multistep process of Raf-1 activation.

An electron microscopic study on the process of acid demineralization of cortical bone.

Demineralization has been shown to foster osteoinductive properties of cortical bone grafts, yet little is known about the process of demineralization and how to control it. The purpose of this study was to investigate the process of cortical bone demineralization by using scanning electron microscopy to evaluate how hydrochloric acid demineralizes cortical bone. Results showed that in the demineralization of diaphyseal cortical bone specimens using hydrochloric acid, a uniformly thick circumferential band of demineralized bone matrix surrounds an inner undecalcified bone core as the process of demineralization occurs. The interface between the demineralized and mineralized section of the bone specimens was extremely sharp. This interface between demineralized and undemineralized bone was noted to advance as a reaction front with increasing demineralization which resulted in continuous shrinkage of the inner cortical bone core. This study suggests that cortical bone demineralization can be best described using an advancing reaction front theory, and this explanation can be used for implementation of the concept of controlled demineralization.

Photodynamic therapy and digital angiography of experimental iris neovascularization using liposomal benzoporphyrin derivative.

PURPOSE: To study the efficacy of liposomal benzoporphyrin derivative (BPD) (Verteportin) for the angiographic visualization and photodynamic therapy (PDT) of experimental iris neovascularization. METHODS: Experimental iris neovascularization was induced in eight cynomolgus monkey eyes by occluding all the branch retinal veins with a dye-yellow (577-nm) laser. Iris angiography was done with sodium fluorescein, indocyanine green (ICG), and liposomal BPD to compare the visualization of normal and neovascular vessels by these three dyes. PDT was performed using an intravenous infusion of liposomal BPD (0.375-0.75 mg/kg), followed by irradiation with 689-nm light from a diode laser/slit-lamp delivery system using 600 mW/cm2 irradiance and 150 J/cm2 fluence. The effect of treatment was followed by iris photography and angiography, and the findings were confirmed by histopathology using light and electron microscopy. RESULTS: Iris fluorescein angiography (FA) showed superficial tortuous and leaky new vessels. Liposomal BPD and ICG angiography of the same eye demonstrated deeper dilated and tortuous iris vessels, with minimal dye leakage. PDT of the iris with irradiation, performed within 20 minutes of the start of dye infusion (0.75 mg/kg), resulted in angiographic and histologic occlusion of iris vessels examined at 24 hours. Three to nine days after PDT, histopathologic examination showed regression of the iris neovascular membrane, with some open vessels. CONCLUSIONS: Liposomal BPD and ICG provided angiographic visualization of deeper normal and neovascular iris vessels. PDT using liposomal BPD leads to effective early closure to experimental iris neovascularization.

KSR modulates signal propagation within the MAPK cascade.

Kinase suppressor of Ras (KSR) is a recently identified component of Ras-dependent signaling pathways. In this report, we show that murine KSR1 (mKSR1) cooperates with activated Ras to promote Xenopus oocyte maturation and cellular transformation and provide evidence that this cooperation occurs by accelerating mitogen and extracellular regulated kinase (MEK) and mitogen-activated protein kinase (MAPK) activation. We also find that mKSR1 associates with Raf-1 at the plasma membrane in a Ras-dependent manner, indicating the presence of a membrane-bound kinase signaling complex. Although mKSR1 is related structurally to Raf-1, our findings reveal striking functional differences between these proteins. In marked contrast to the isolated amino- and carboxy-terminal domains of Raf-1, the KSR amino terminus also cooperates with Ras, whereas the carboxy-terminal kinase domain blocks Ras signaling as well as MEK and MAPK activation. The isolated KSR kinase domain suppressed Xenopus oocyte maturation, cellular transformation, and Drosophila eye development, suggesting that separation of the amino- and carboxy-terminal domains has uncoupled the normal regulation of KSR as a positive effector of Ras signaling. Together, our findings indicate that mKSR1 is an integral component of the MAPK module functioning via a novel mechanism to modulate signal propagation between Raf-1, MEK1, and MAPK.

Intravenous infusion of liposomal benzoporphyrin derivative for photodynamic therapy of experimental choroidal neovascularization.

OBJECTIVE: To compare the effectiveness of photodynamic therapy to close experimental choroidal neovascularization using an intravenous infusion of liposomal benzoporphyrin derivative (verteporfin) with previous work using a rapid intravenous injection, before initiating clinical trials. METHODS: Choroidal neovascularization was induced in cynomolgus monkey eyes using argon laser. Liposomal benzoporphyrin derivative was delivered by an intravenous infusion pump for 10 or 32 minutes at a dose of 0.375 mg/kg. Irradiation was performed with 689- or 692-nm laser light (600-mW/cm2 irradiance and 150-J/cm2 fluence) in 7 normal eyes and 11 eyes with choroidal neovascularization between 30 and 105 minutes after the start of dye infusion. Findings were documented by fundus photography, fluorescein angiography, and light and electron microscopy. RESULTS: Irradiation within 32 to 50 minutes of the start of the fast (10 minutes) or slow (32 minutes) dye infusion resulted in closure of choroidal neovascularization. In normal eyes, this technique caused choriocapillaris closure and retinal pigment epithelium damage with minimal damage to surrounding tissues. CONCLUSION: Photodynamic therapy using intravenous infusion of liposomal benzoporphyrin derivative selectively closed experimental choroidal neovascularization. This may be a suitable modality for clinical use.

Liposomal benzoporphyrin derivative verteporfin photodynamic therapy. Selective treatment of choroidal neovascularization in monkeys.

PURPOSE: The authors have previously shown that photodynamic therapy (PDT) using lipoprotein-delivered benzoporphyrin derivative mono-acid (BPD) effectively closed experimental choroidal neovascularization (CNV). In the current study, the authors used a clinical preparation, liposomal BPD verteporfin in the same model, with experiments designed to establish optimal dye and light doses, and the timing of laser light irradiation after dye injection, for effective and selective closure of CNV. METHODS: Experimental CNV was induced in the maculae of cynomolgus monkeys. Liposomal BPD verteporfin was injected intravenously at doses of 1.0, 0.5, 0.375, and 0.25 mg/kg. Laser light at 692 nm then was applied to CNV, with an irradiance of 600 mW/cm2 and fluence of 150 J/cm2, at various times after dye injection, ranging from 5 to 120 minutes. Treatment effect was assessed by fundus photography and fluorescein angiography and confirmed by light and electron microscopy. The PDT of experimental CNV was studied to assess efficacy; PDT performance on normal eyes was studied to investigate selectivity. RESULTS: The CNV closure was demonstrated by fluorescein angiography and histopathologic findings at all tested dye doses. A dye dose of 0.375 mg/kg, with laser light irradiation applied 20 to 50 minutes after dye injection, optimized CNV closure with minimal retinal and choroidal damage. No major local adverse effects were noted, and the drug was well tolerated systematically. CONCLUSIONS: Liposomal BPD verteporfin is a potent photosensitizer, and PDT using this dye is a potentially effective and selective treatment for CNV.

Photodynamic therapy inhibits experimental allograft rejection. A novel approach for the development of vascular bioprostheses.

BACKGROUND: Biological vascular allografts have proved unsatisfactory because of thrombosis, occlusion, and aneurysmal degeneration during chronic rejection. Photodynamic therapy (PDT), a technique that leads to the production of cytotoxic free radicals, was investigated as a novel method to prepare arterial allografts. METHODS AND RESULTS: Shortly after impregnation with the photosensitizer drug chloroaluminum sulfonated phthalocyanine, infrarenal aortas of ACI rats were PDT-treated and orthotopically grafted in Lewis rats (PDT). The transplanted grafts were sequentially analyzed at 2, 4, and 8 weeks by morphometry, immunohistochemistry, and scanning electron microscopy. Of 25 untreated allografts, 4 (16%) developed aneurysms compared with 0 of 33 in PDT or untreated isografts (ISO, P < .001). PDT treatment of allografts significantly inhibited intimal hyperplasia (P < .001) and resulted in intimal areas comparable to those in ISO. However, medial thickness in both control allografts and PDT grafts was markedly decreased compared with ISO. External graft diameters of control allografts at 8 weeks were significantly enlarged (P < .02) compared with PDT or ISO. At all time points, T lymphocytes were found in a substantially larger number in untreated control grafts than in PDT or ISO. Scanning electron microscopy at 4 weeks confirmed complete repopulation with endothelial cells in PDT, which was not seen in the control allografts. CONCLUSIONS: Our findings suggest that local PDT treatment of arterial allografts inhibits inflammatory infiltration, aneurysmal dilatation, and development of intimal hyperplasia and may be used to develop vascular bioprostheses for use in humans.