Outcomes with Bridging Radiation Therapy Prior to CAR-T Cell Therapy in Pts with Aggressive B Cell Lymphomas

PURPOSE/OBJECTIVE(S)

Select patient (pts) with relapsed/refractory aggressive B cell lymphoma may benefit from bridging radiation (bRT) prior to anti-CD19-directed chimeric antigen receptor T cell therapy (CART). Here, we examined pt and treatment factors associated with outcome after bRT and CART.

MATERIALS/METHODS

We retrospectively reviewed adults with DLBCL who received bRT prior to axicabtagene ciloleucel 11/2017-12/2022. Clinical/treatment characteristics, response, and toxicity were extracted. Progression free survival (PFS), disease specific survival (DSS) and overall survival (OS) were modeled using Kaplan-Meier for events distributed over time, or binary logistic regression for disease response. Fisher's Exact Test or Mann-Whitney U methods were used.

RESULTS

Among 40 pts, 11 (28%) had limited stage disease at apheresis, and 14 (35%) received bRT in addition to bridging systemic therapy. Thirty-two (80%) pts received bRT post-leukapheresis. bRT was delivered with a median dose of 30 Gy (range: 4-46) in 10 fractions (range: 2-23). Eighteen (45%) pts received <30 Gy. Twenty-two pts (55%) received bRT comprehensively to all sites of disease, including 9 pts who had limited stage. Eleven pts had bulky disease (≥ 10 cm) at the time of bRT. After CART, 4 pts (10%) experienced Grade ≥3 cytokine release syndrome (CRS), 16 (40%) had Grade ≥2 CRS, and 16 (38%) had Grade ≥3 neurotoxicity. Twenty-three pts (57.5%) had CR at 30 days post-CART infusion. Nine had PR (22.5%), of whom 2 pts eventually developed CR at three months and 1 at nine months. Eight pts (20%) had either PD or SD. Of 23 pts who experienced CR, 11 relapsed-6 at three months and 5 at six months. At a median follow up of 9.6 months (95% CI: 6.6-16.2), 22 pts relapsed: 6 (27.3%) in-field, 10 (5.5%) out-of-field, 4 (18.2%) both, and 2 (9.1%) unknown. The median PFS was 8.87 months and median OS was 22 months. PFS at 1 year was 70% (53-82) and at 2 years was 42% (27-57). OS at 1 and 2 years was 72.5% (56-84) and 51% (34-65), respectively. Seventeen pts (42.5%) remain alive at last follow-up, 13 (76.5%) of whom have no evidence of disease (NED). On univariate analysis, OS and PFS at 1 year were 67% (43-83) and 49% (27-68) for those who received RT comprehensively (n = 22), and 41.9% (19-64) and 33.3% (14-54) for those who did not (n = 18; both p≤0.03). Disease bulk (≥10 cm) was associated with significant decrement in DSS (p = 0.03), but not PFS (p = 0.16) or OS (p = 0.24). Among pts treated comprehensively with bRT (n = 22), there was no association of tumor bulk with OS, PFS, or DSS (p>0.2). IPI ≥3 was associated with worse DSS (p = 0.045) and trended towards worse PFS (p = 0.054), but not OS (p = 0.23). There was no difference in PFS, OS, or DSS between pts who received bRT or chemoRT (p>0.3).

CONCLUSION

bRT and CART is a good treatment strategy for select pts with aggressive B cell lymphoma. When feasible, and with a caveat that other variables influence patient disposition, bRT for CART is associated with improved outcomes after comprehensive RT to all sites of disease.

Outcomes and Toxicities in Patients with Diffuse Large B-Cell Lymphoma of the Gastrointestinal Tract

PURPOSE/OBJECTIVE(S)

Diffuse large B-cell lymphoma (DLBCL) involving the gastrointestinal (GI) tract is rare and long-term outcomes are not well defined. Combined modality therapy (CMT) with radiotherapy (RT) in addition to systemic therapy in this setting is not commonly pursued. We aim to characterize outcomes in patients with GI DLBCL treated with systemic therapy, with or without RT.

MATERIALS/METHODS

Patients diagnosed with DLBCL of the GI tract (with or without mesenteric involvement) treated at a single institution from 1988-2022 were retrospectively reviewed on an IRB-approved protocol. Clinical and treatment data were collected including adverse events (AE; acute vs late defined as before or 4 weeks after therapy end). Kaplan-Meier and Cox regression models were used to estimate survival.

RESULTS

Of 207 patients, 62% were male and median age at diagnosis was 63 (IQR 52-73). Gastric involvement was most common (n = 130, 63%), followed by small intestines (n = 48, 23%) and colon/rectum (n = 24, 12%). Most presented with early-stage disease (n = 124, 60%), with a median IPI score of 1. All patients received chemotherapy. Of 182 treated with CHOP/EPOCH, 36 (20%) were treated in the pre-rituximab era while 146 (80%) received rituximab. 66 patients (32%) were treated with RT, 89% as part of first line CMT. 50 cases (76%) received consolidative RT, while 10 (15%) targeted residual gross disease and 4 (6%) targeted distant sites. Median dose and fractionation were 36Gy (IQR 30.6-39.6) in 18 fractions (IQR 17-22). Over half (n = 132, 64%) developed grade 3+ acute chemotherapy AEs, and the most common were anemia (n = 64), febrile neutropenia (n = 40), and neutropenia (n = 20). Grade 3+ late chemotherapy AEs occurred in 14 patients (7%). Acute grade 3+ radiation AEs were uncommon (n = 2, 3%; colitis, emesis). No grade 3+ late radiation AEs were noted. Median follow-up was 46 months (IQR 16-97). 169 (81.6%) had a complete response (CR), with 154 (91%) after first line chemotherapy, 9 (5%) after second line, and 6 (4%) after RT. CR was defined by PET (62%), endoscopy (22%), CT (9%), or other methods (7%). The 5-year progression-free survival for those treated with one line of chemotherapy with or without RT was 95%. Median overall survival (OS) was not reached. Improved OS was associated with early-stage disease (p = 0.003), low IPI (p = 0.001), fewer chemotherapy lines (p<0.001), and CR (p<0.001). OS did not differ by gender, age, immunophenotype, GI site, SUVmax, or RT. Patients with early stage DLBCL treated with RT in the post-rituximab era received fewer chemotherapy cycles compared to those treated without RT (p = 0.02; median of 4 (IQR 3-6) vs 6 cycles (IQR 4-6)), with no OS difference.

CONCLUSION

GI DLBCL patients have favorable outcomes after CMT with minimal late toxicity. CMT with RT to the GI tract is well tolerated with no OS difference compared to chemotherapy alone, and may mitigate risks from additional chemotherapy cycles for selected early-stage patients.

Ultra Low-Dose Radiation for Extranodal Marginal Zone Lymphoma of the Lung

PURPOSE/OBJECTIVE(S)

Definitive radiation treatment (RT) for extranodal marginal zone lymphoma (ENMZL) of mucosal associated lymphoid tissue historically involves treatment to 24-30 Gy. There is increasing data supporting the use of ultra-low dose RT as part of a response-adapted approach in the treatment of orbital and gastric ENMZL. With this approach, patients receive initial treatment with 4 Gy, and additional RT is considered for those with persistent or locally progressive disease. However limited data to date assesses the efficacy of 4 Gy in the management of ENMZL of the lung.

MATERIALS/METHODS

We performed an IRB-approved retrospective review of 17 patients with ENMZL of the lung treated with 4 Gy between 7/2015 and 12/2022 with response assessed after RT. Clinical/treatment characteristics, response, and toxicity were extracted from medical records. Statistics were performed using Mann-Whitney U and Fisher's Exact Test.

RESULTS

Eight patients (47%) were female, 15 (88%) white, and 1 (6%) Hispanic. Median age at RT was 66 (interquartile range (IQR) 59-77). All had disease limited to the lung at diagnosis and 15 had stage IE disease. Four patients (24%) were diagnosed incidentally on screening/surveillance imaging in the absence of symptoms. Sixteen patients received 4 Gy in 2 fractions, while one patient received a single fraction of 4 Gy. Median SUVmax prior to RT was 4.5 (IQR 3.2-7.2). Median planning target volume (PTV) was 74 cc (IQR 47-130cc). Six patients (35%) had respiratory symptoms prior to RT, which improved or resolved in 3 (50%). A larger PTV was associated with improvement in symptoms following RT with a median PTV of 266 cc (IQR 171-402) in those who experienced improvement vs. 64 cc (IQR 42-100) in those who did not (p = 0.032). One patient experienced toxicity following RT with pleuritic chest pain, which resolved with corticosteroids. At a median follow-up of 15 months following RT (IQR 7-43 months), the overall response rate (ORR) was 100% (CR, n = 15; PR, n = 2). Fourteen patients had follow-up PET/CT, of whom 13 had a complete metabolic response (CMR) at a median of 3 months following RT (IQR 3-5 months). Two additional patients had a complete response (CR) on CT while one had a partial response on CT. Achieving a CR was not associated with SUV prior to RT (p = 0.50) or PTV size (p = 0.62). In patients with stage IE disease, the ORR rate was 100% and there have been no distant failures to date. Fifteen of 17 patients were alive at last follow-up; two passed away of unrelated causes (one from Alzheimer's disease and one from recurrent squamous cell carcinoma).

CONCLUSION

Ultra-low dose radiation of 4 Gy is associated with excellent local control in the management of ENMZL of the lung and is very well tolerated. Four Gy was effective for local control and symptom palliation even for larger tumors and is an effective initial therapy as part of a response-adapted approach even in limited stage patients.

Characterization of Lymphopenia during Bridging Radiation Therapy Prior to CAR-T Cell Therapy in Patients with Aggressive B Cell Lymphomas

PURPOSE/OBJECTIVE(S)

Bridging RT (bRT) may be used as a strategy for disease control in patients with relapsed/refractory aggressive B cell lymphoma treated with anti-CD19-directed chimeric antigen receptor T-cell therapy (CART). The correlation of treatment-related lymphopenia with adverse outcomes in patients has been widely documented in several malignancies. Here, we assessed lymphocyte kinetics during bRT and impact on clinical outcome.

MATERIALS/METHODS

After IRB-approval, records were retrospectively reviewed for adults with DLBCL who received bRT for axicabtagene ciloleucel 11/2017-12/2022. Clinical/treatment characteristics, lab values, and outcomes were extracted. ALC Δ RT was computed by subtracting pre-RT ALC from post-RT ALC count. Survival was modeled using Kaplan-Meier for events distributed over time, or binary logistic regression for disease response. Fisher's Exact Test or Mann-Whitney U methods were used.

RESULTS

Forty patients met inclusion criteria. Fourteen (35%) received bRT with systemic therapy. Thirty-two (80%) patients received bRT that started post-leukapheresis. bRT was delivered with a median dose of 30 Gy (range: 4-46) in 10 fractions (range: 2-23). Twenty-three patients (57.5%) had CR at 30 days post-CART infusion. Nine had PR (22.5%), and 8 patients (20%) had PD or SD. Median PFS was 8.9 months and median OS was 22 months. The pre-RT ALC mean ± SD was 0.74 ± 0.49 K/µL, and post-RT was 0.43 ± 0.35 K/µL. The absolute ALC Δ RT was 0.31 ± 0.43 K/µL, and ratio post-RT/pre-RT was 0.74 ± 0.64. Stratifying by receipt of bRT alone or with systemic therapy, there was no statistically significant difference in ALC count post-RT (chemoRT: 0.33 ± 0.23 vs. RT: 0.48 ± 0.4, p = 0.2), but there was a lower ALC count pre-RT in the chemoRT group (0.5 ± 0.3 vs. 0.87 ± 0.52 for RT alone, p = 0.02). Post-RT ALC was not significantly associated with CR/PR vs. PD/SD, or with DSS, PFS, or OS. A greater drop in ALC Δ RT trended towards association with improved 90-day response (p = 0.066), without correlation with DSS, OS, or response at 30 days. Median dose per fraction was lower among patients that got pre-leukapheresis RT (2.25 vs. 2.5, p = 0.04), but total dose of bRT or number of fractions was not significantly different. Otherwise, the groups were similar in terms of stage, disease bulk, or comprehensive vs. focal bRT. The average decrease in ALC post-RT for patients who received bRT prior to apheresis was 0.215 K/µL, compared to 0.268 K/µL for patients who received bRT post-apheresis (p = 0.75). Treatment with pre-leukapheresis bRT or ALC Δ RT among these patients were not associated with worse DFS, PFS, or OS (p>0.15).

CONCLUSION

Post-bRT ALC and reduction in ALC during bRT is not associated with worse treatment response or survival outcomes after CAR-T cell treatment in aggressive B cell lymphoma. Pre-leukapheresis bRT did not appear to substantially impact ALC, and ALC Δ RT among these patients were not associated with worse outcomes.

Effect of femtosecond laser interaction with human fibroblasts: a preliminary study

In in vitro methods and cell culture models, femtosecond (fs) laser interaction has been employed to assess its effect on the proliferation and morphology of human skin fibroblasts. We cultured a primary human skin fibroblast cell line on a glass plate, passages 17-23. The cells were irradiated with a 90-fs laser at a wavelength of 800 nm and a repetition rate of 82 MHz. The target received an average power of 320 mW for 5, 20, and 100 s, corresponding to the radiation exposures of 22.6, 90.6, and 452.9 J/cm2, respectively. Using a laser scanning microscopy technique, the photon densities were measured to be 6.4 × 1018, 2.6 × 1019, and 1.3 × 1020 photons/cm2 in a spot area of 0.07 cm2; the recorded spectra were obtained from the laser interaction after 0.00, 1.00, 25.00, and 45.00 h. The cell count and morphological changes showed that the cultured cells were affected by laser irradiation under photon stress; some fibroblasts were killed, while others were injured and survived. We discovered evidence of the formation of several coenzyme compounds, such as flavin (500-600 nm), lipopigments (600-750 nm), and porphyrin (500-700 nm). This study is motivated by the future development of a novel, ultra-short fs laser system and the need to develop a basic in vitro understanding of photon-human cell interaction. The cell proliferation indicated that cells are partly killed or wounded. The exposure of fibroblasts to fs laser fluence up to 450 J/cm2 accelerates cell growth of the viable residual cell.

Impact of Moderna mRNA-1273 Booster Vaccine on Fully Vaccinated High-Risk Chronic Dialysis Patients after Loss of Humoral Response

The long-term effect of protection by two doses of SARS-CoV-2 vaccination in patients receiving chronic intermittent hemodialysis (CIHD) is an urging question. We investigated the humoral and cellular immune response of 42 CIHD patients who had received two doses of SARS-CoV-2 vaccine, and again after a booster vaccine with mRNA-1273 six months later. We measured antibody levels and SARS-CoV-2-specific surrogate neutralizing antibodies (SNA). Functional T cell immune response to vaccination was assessed by quantifying interferon-γ (IFN-γ) and IL-2 secreting T cells specific for SARS-CoV-2 using an ELISpot assay. Our data reveal a moderate immune response after the second dose of vaccination, with significantly decreasing SARS-CoV-2-specific antibody levels and less than half of the study group showed neutralizing antibodies six months afterwards. Booster vaccines increased the humoral response dramatically and led to a response rate of 89.2% for antibody levels and a response rate of 94.6% for SNA. Measurement in a no response/low response (NR/LR) subgroup of our cohort, which differed from the whole group in age and rate of immunosuppressive drugs, indicated failure of a corresponding T cell response after the booster vaccine. We strongly argue in favor of a regular testing of surrogate neutralizing antibodies and consecutive booster vaccinations for CIHD patients to provide a stronger and persistent immunity.

Bidirectional reflectance measurement of tungsten samples to assess reflection model in WEST tokamak

This paper presents the measurement of the bidirectional reflectance distribution function of tungsten (W) samples and the resulting reflection models in the nuclear fusion device WEST (tokamak). For this, an experimental gonio-spectrophotometer was developed to fully characterize the material's optical and thermal-radiative properties of metallic samples with different roughnesses. Ray-tracing photonic simulation was then carried out to predict the photon behavior in a fully metallic environment as a function of reflectance measurement. Low emissivity (0.1 at 4 μm) and highly specular reflectance (fitting with a Gaussian distribution around the specular direction with a small width lower than 10°) are found for W samples. These measurements have been used as input for the photonic simulation, and the resulting synthetic image reproduced the reflection features well on the upper divertor, detected in WEST infrared experimental images.

Effect of high-flow vs. low-flow nasal plus mouthguard oxygen therapy on hypoxaemia during sedation: a multicentre randomised controlled trial

Whether high-flow vs. low-flow nasal oxygen reduces hypoxaemia for sedation during endoscopic retrograde cholangiopancreatography is currently unknown. In this multicentre trial, 132 patients ASA physical status 3 or higher, BMI > 30 kg.m^-2 or with known or suspected obstructive sleep apnoea were randomly allocated to high-flow nasal oxygen up to 60 l.min^-1 at 100% F_I O₂ or low-flow nasal oxygen at 4 l.min^-1 . The low-flow nasal oxygen group also received oxygen at 4 l.min^-1 through an oxygenating mouthguard, totalling 8 l.min^-1 . Primary outcome was hypoxaemia, defined as S_p O₂ < 90% regardless of duration. Hypoxaemia occurred in 7.7% (5/65) of patients with high-flow and 9.1% (6/66) with low-flow nasal oxygen (percentage point difference -1.4%, 95%CI -10.9 to 8.0; p = 0.77). Between the groups, there were no significant differences in frequency of hypoxaemic episodes; lowest S_p O₂ ; peak transcutaneous carbon dioxide; hypercarbia (transcutaneous carbon dioxide > 2.66 kPa from baseline); requirement of chin lift/jaw thrust; nasopharyngeal airway insertion; bag-mask ventilation; or tracheal intubation. Following adjustment for duration of the procedure, the primary outcome remained non-significant. In high-risk patients undergoing endoscopic retrograde cholangiopancreatography, oxygen therapy with high-flow nasal oxygen did not reduce the rate of hypoxaemia, hypercarbia or the need for airway interventions, compared with combined oral and nasal low-flow oxygen.

Is dental general anaesthesia in children an outdated concept? A retrospective analysis

AIM

The aim of this retrospective study was to determine the prevalence of caries and treatment needs in the collective of patients ?16 years of age, who underwent scheduled dental general anaesthesia (DGA) at the University Clinic of Innsbruck from January 2015 to June 2019, with respect to demographic factors.

MATERIALS AND METHODS

A retrospective analysis of children's diagnoses, demographics, and dental treatment under general anaesthesia in Innsbruck, Austria, from 2015 to 2019 was performed. Anonymised demographic data (age; gender; the presence or absence of general disease or disablement; parents' first language (German- (GS) or non-German-speaking (non-GS), reflecting ethnicity; and the number of teeth restored and extracted under DGA were collected from patients' files. Data was analysed by means of descriptive and comparative statistics.

RESULTS

The main group consisted of 545 subjects at a median age of 5.3 (IQR 4.4-6.6) years, who had exclusively primary teeth and or first molars that received restorations or were extracted. Of the subjects, 84.4% were classified with uncooperativeness due to dental anxiety and 15.6% with systemic diseases or intellectual and or physical disablement. In this group, 47.9% were GS and 52.1% were non-GS or had GS or non- GS parents. In the total sample, 5 (IQR 3-7) primary teeth were restored and 4 (IQR 4-7) extracted. Subgroup analysis revealed statistically significant differences in the number of extracted primary teeth between children with and without systemic diseases or disablement - 3 (IQR 1-5) versus 4 (IQR 2-7) - and between children of GS and non-GS parents - 4 (IQR 2-6) versus 5 (IQR 3-7.8). Zero (IQR 0-0) first molars were filled and extracted.

CONCLUSION

Within the study collective of children in poor oral health, the offspring of non-GS families were overrepresented (compared to their prevalence in the total population) and displayed a higher prevalence of deep caries than those of GS parents. By intensifying and special gearing of prophylactic measures to the non-GS population and promoting the parents' insight into the importance of oral hygiene and regular dental attendance, the demand for scheduled DGA might be greatly reduced. In the small share of children who suffer from severe diseases or disablement and are thus unable to cooperate with home care or dental treatment, DGA will remain the treatment of choice.

Cleaning of first mirrors in ITER by means of radio frequency discharges

First mirrors of optical diagnostics in ITER are subject to charge exchange fluxes of Be, W, and potentially other elements. This may degrade the optical performance significantly via erosion or deposition. In order to restore reflectivity, cleaning by applying radio frequency (RF) power to the mirror itself and thus creating a discharge in front of the mirror will be used. The plasma generated in front of the mirror surface sputters off deposition, restoring its reflectivity. Although the functionality of such a mirror cleaning technique is proven in laboratory experiments, the technical implementation in ITER revealed obstacles which needs to be overcome: Since the discharge as an RF load in general is not very well matched to the power generator and transmission line, power reflections will occur leading to a thermal load of the cable. Its implementation for ITER requires additional R&D. This includes the design of mirrors as RF electrodes, as well as feeders and matching networks inside the vacuum vessel. Mitigation solutions will be evaluated and discussed. Furthermore, technical obstacles (i.e., cooling water pipes for the mirrors) need to be solved. Since cooling water lines are usually on ground potential at the feed through of the vacuum vessel, a solution to decouple the ground potential from the mirror would be a major simplification. Such a solution will be presented.

Zolpidem test and catatonia

WHAT IS KNOWN AND OBJECTIVE

There is no consensus regarding treatment of catatonia and the main recent therapeutic progress has been the development of the zolpidem diagnostic and therapeutic test. We report on the use of this test in one of our patients.

CASES SUMMARY

Mr. S. suffered from a paranoid schizophrenia. Three episodes of catatonia are described to illustrate the effect of zolpidem in a patient for whom lorazepam was ineffective or inadequate.

WHAT IS NEW AND CONCLUSION

Zolpidem with appropriate testing appears to be a credible alternative to electroconvulsive therapy or increased lorazepam dosing and allows continuation of antipsychotic administration.

Validation of reference materials for uranium radiochronometry in the frame of nuclear forensic investigations

The results of a joint effort by expert nuclear forensic laboratories in the area of age dating of uranium, i.e. the elapsed time since the last chemical purification of the material are presented and discussed. Completely separated uranium materials of known production date were distributed among the laboratories, and the samples were dated according to routine laboratory procedures by the measurement of the (230)Th/(234)U ratio. The measurement results were in good agreement with the known production date showing that the concept for preparing uranium age dating reference material based on complete separation is valid. Detailed knowledge of the laboratory procedures used for uranium age dating allows the identification of possible improvements in the current protocols and the development of improved practice in the future. The availability of age dating reference materials as well as the evolvement of the age dating best-practice protocol will increase the relevance and applicability of age dating as part of the tool-kit available for nuclear forensic investigations.

Chemistry of Bacteriochlorophyll b: Identification of Some (Photo)Oxidation Products

Photoreactions of bacteriochlorophyll b have been studied. They all arise from reactions at the Δ8,81 double-bond. The Δ7,8-isomerisation product 3 is formed under anaerobic conditions. Irradiation in the presence of oxygen leads to three products arising from an autoxidation reaction involving singlet oxygen. The structures of two of them (4, 5) have been established from their methylpheophorbides 10 and 11 containing an 8-acetyl and 8-(meth)oxyethyl-substituent, respectively, in addition to the isomerized Δ7,8-double bond.

Inflammation and atrial remodeling after a mountain marathon

Endurance athletes have an increased risk of atrial fibrillation. We performed a longitudinal study on elite runners of the 2010 Jungfrau Marathon, a Swiss mountain marathon, to determine acute effects of long-distance running on the atrial myocardium. Ten healthy male athletes were included and examined 9 to 1 week prior to the race, immediately after, and 1, 5, and 8 days after the race. Mean age was 34.9 ± 4.2 years, and maximum oxygen consumption was 66.8 ± 5.8 mL/kg*min. Mean race time was 243.9 ± 17.7 min. Electrocardiographic-determined signal-averaged P-wave duration (SAPWD) increased significantly after the race and returned to baseline levels during follow-up (128.7 ± 10.9 vs. 137.6 ± 9.8 vs. 131.5 ± 8.6 ms; P < 0.001). Left and right atrial volumes showed no significant differences over time, and there were no correlations of atrial volumes and SAPWD. Prolongation of the SAPWD was accompanied by a transient increase in levels of high-sensitivity C-reactive protein, proinflammatory cytokines, total leucocytes, neutrophil granulocytes, pro atrial natriuretic peptide and high-sensitivity troponin. In conclusion, marathon running was associated with a transient conduction delay in the atria, acute inflammation and increased atrial wall tension. This may reflect exercise-induced atrial myocardial edema and may contribute to atrial remodeling over time, generating a substrate for atrial arrhythmias.

Functional characterization of Fospeg, and its impact on cell cycle upon PDT of Huh7 hepatocellular carcinoma cell model

BACKGROUND

Although several treatment options are available for hepatocellular carcinoma (HCC), their application is mostly restricted to early diagnosed cases or includes liver transplantation, which is rarely available due to donor scarcity. The attractiveness of PDT as a cancer treatment does not only come from its minimal invasiveness, but also from the high selectivity due to tumor localization that can be applied. Precise focusing of light on tumor lesions will result in tumor-specific PDT activation. Novel photosensitizers can be applied in such low concentrations that cells not subjected to irradiation remain healthy. The lethal effect and mechanism of death induction of the photosensitizer Fospeg has never been studied on hepatocellular carcinoma. The aim of the present study is to functionally analyze the impact of PDT on Huh-7 HCC cell line, as well as to analyze its impact on cell cycle protein expression.

METHODS

Cellular viability, and proliferation assays were conducted via MTT and BrdU assay, respectively. Transfected cell models of Huh7 with different constructs harboring cell cycle genes and downstream reporter luciferase gene were generated.

RESULTS

Our results show a statistically significant decrease in both viability and proliferation of Huh-7 cells following PDT, while maintaining Fospeg and laser concentrations far below toxic levels. Proliferative cell cycle genes show a tendency of inhibition, while p53 levels show a significant increase following PDT.

CONCLUSION

Fospeg-mediated PDT is a promising strategy for treatment of hepatocellular carcinoma and needs to be further explored in vivo.

Spectroscopic reflectometry of mirror surfaces during plasma exposure

An in situ spectroscopic reflectometry system has been built to investigate the evolution of the specular reflectivity spectrum of ITER first mirror samples during plasma exposure. Results are presented for three different types of molybdenum mirror samples that were exposed to deuterium plasma, including single crystalline, nanocrystalline, and polycrystalline molybdenum. The results show good agreement with ex situ measurements of the reflectivity spectrum before and after exposure and extend the results obtained in previous experiments.

Rhodium and silicon system: I. Glassy metallic alloy formation

Detailed characterizations of rhodium/silicon films prepared by co-deposition using magnetron sputtering have been carried out on silicon substrates at room temperature. Effects of the silicon content incorporated in the film on the chemical bonding state and crystallinity were investigated using XPS/UPS, XRD and SEM. It should be emphasized that XPS/UPS measurements are carried out without breaking the vacuum to avoid any contamination of the film. All x-ray diffraction patterns revealed a high degree of amorphization. There is only a weak Rh pattern and a weak Rh(2)Si pattern for 20 and 37 at.% of Si, respectively, i.e. showing a formation of glassy metallic alloy. A negative shift in the Rh core level binding energy for rhodium-rich alloys is mainly referred to relaxation effects due to a high density of d-states near the Fermi level. The filling of the d-states is completed between 25 and 40 atomic concentration of Si. Valence orbital transformation due to the Si-Rh interactions is causing the progressive positive shift in the binding energy for higher silicon content.

Rhodium and silicon system: II. Rhodium silicide formation

Detailed characterizations of rhodium/silicon films prepared by co-deposition using magnetron sputtering have been carried out on silicon substrates at room temperature up to 900 degrees C. The properties of the films were investigated using XPS/UPS, XRD, SIMS, SEM and AFM techniques. It should be emphasized that XPS/UPS measurements are carried out without breaking the vacuum to avoid any contamination of the film. Up to 500 degrees C an interdiffusion between the oxidized silicon wafer and the deposited Rh/Si film occurred leading to hole formation in the entire film at 900 degrees C. Diffraction patterns for the compounds Rh(2)Si, Rh(5)Si(3), RhSi and Rh(3)Si(4) were measured. Upon annealing the covalent character is increased and for the samples forming the compound RhSi the valence band structure is markedly changed. Depth profiling (XPS and SIMS) reveals a stable composition in the bulk of the film. For these measurements the silicon-rich alloy in the interfacial layer is probably an effect of sputtering, by implanting the Rh atoms into the silicon substrate. A previously reported negative shift for the compound Rh(5)Si(3) could be connected to the sample preparation, as sputtering of the surface is reducing the silicon content and inducing a glassy state. For the first phase Rh(2)Si formed on the rhodium-rich side the shift in binding energy is unclear, for all the other compounds encountered in this work a positive shift relative to pure rhodium was found.

Patient radiation doses in the most common interventional cardiology procedures in Croatia: first results

Apart from its benefits, the interventional cardiology (IC) is known to generate high radiation doses to patients and medical staff involved. The European Union Medical Exposures Directive 97/43/Euroatom strongly recommend patient dosimetry in interventional radiology, including IC. IC patient radiation doses in four representative IC rooms in Croatia were investigated. Setting reference levels for these procedures have difficulties due to the large difference in procedure complexity. Nevertheless, it is important that some guideline values are available as a benchmark to guide the operators during these potentially high-dose procedures. Local and national diagnostic reference levels (DRLs) were proposed as a guidance. A total of 138 diagnostic (coronary angiography, CA) and 151 therapeutic (PTCA, stenting) procedures were included. Patient irradiation was measured in terms of kerma-area product (KAP), fluoroscopy time (FT) and number of cine-frames (F). KAP was recorded using calibrated KAP-meters. DRLs of KAP, FT and F were calculated as third quartile values rounded up to the integer. Skin doses were assessed on a selected sample of high skin dose procedures, using radiochromic films, and peak skin doses (PSD) were presented. A relative large range of doses in IC was detected. National DRLs were proposed as follows: 32 Gy cm(2), 6.6 min and 610 frames for CA and 72 Gy cm(2), 19 min and 1270 frames for PTCA. PSD <1 Gy were measured in 72 % and PSD >2 Gy in 8 % of selected patients. Measuring the patient doses in radiological procedures is required by law, but rarely implemented in Croatia. The doses recorded in the study are acceptable when compared with the literature, but optimisation is possible. The preliminary DRL values proposed may be used as a guideline for local departments, and should be a basis for radiation reduction measures and quality assurance programmes in IC in Croatia.

High-resolution 3T MR angiography of the carotid arteries: comparison of manual and semiautomated quantification of stenosis

BACKGROUND AND PURPOSE

High-resolution contrast-enhanced MR angiography (CE-MRA) acquired at 3T exquisitely depict carotid artery (CA) stenosis. In this study, we examined the agreement of different vessel-analysis tools with manual quantitative measurement by 2 readers using CE-MRA data.

MATERIALS AND METHODS

Three vessel tools determining the trajectory of the vessel of interest and, subsequently, the vessel dimensions were tested against manual measurements. Diameter and area stenoses were calculated. CE-MRA data of 32 patients with CA stenosis were evaluated. The agreement between different measurements was assessed with kappa statistics after categorizing stenosis (<25%, 25%-49%, 50%-69%, 70%-99%, and 100%).

RESULTS

The mean grades of stenosis based on diameter measurements were 59% (readers) and 60%/56%/59% based on the analysis with tools A/B/C (P = 0.2-0.7). kappa values for agreement between readers and the vessel tools were 0.73/0.77/0.77 (tools A/B/C for all CAs) and 0.66/0.74/0.75 (for the symptomatic side). The mean grades of stenoses based on area measurements for tools A/B/C were 68%/63%/69% versus 58% for readers. Values from readers differed significantly from those for tools A and C (P < 0.01). kappa values for agreement between readers and the vessel tools were 0.66/0.55/0.64 (for all CAs) and 0.53/0.44/0.57 (for the symptomatic side).

CONCLUSIONS

The automated approach allows accurate assessment of vessel dimensions in MRA images at least for diameter measurements according to the North American Symptomatic Carotid Endarterectomy Trial criteria.

Recombinant inbred line differential identifies race-specific resistance to phytophthora root rot in Capsicum annuum

A differential series is the normal method for identification of races within a plant pathogen and a host interaction. A host differential is extremely useful for phytopathological as well as breeding purposes. A set of recombinant inbred lines (RILs) were developed and characterized for race differentiation of Phytophthora root rot caused by Phytophthora capsici. The highly resistant Capsicum annuum accession Criollo de Morelos-334 was hybridized to a susceptible cultivar, Early Jalapeno, to generate the RIL population. The host differential characterized 17 isolates of P. capsici into 13 races. The establishment of a stable host differential for the P. capsici and C. annuum interaction will assist researchers in understanding the complex inheritance of resistance to Phytophthora root rot and to develop resistant cultivars.