Mild hyperthermia with magnetic resonance- guided high intensity focused ultrasound combined with salvage chemoradiation for recurrent rectal cancer.

INTRODUCTION: Pelvic recurrences from rectal cancer present a challenging clinical scenario. Hyperthermia represents an innovative treatment option in combination with concurrent chemoradiation to enhance therapeutic effect. We provide the initial results of a prospective single center feasibility study (NCT02528175) for patients undergoing rectal cancer retreatment using concurrent chemoradiation and mild hyperthermia with MR-guided high intensity focused ultrasound (MR-HIFU). METHODS: All patients were deemed ineligible for salvage surgery and were evaluated in a multidisciplinary fashion with a surgical oncologist, radiation oncologist and medical oncologist. Radiation was delivered to a dose of 30.6 Gy in 1.8 Gy per fraction with concurrent capecitabine. MR-HIFU was delivered on days 1, 8 and 15 of concurrent chemoradiation. Our primary objective was feasibility and toxicity. RESULTS: Six patients (total 11 screened) were treated with concurrent chemoradiation and mild hyperthermia with MR-HIFU. Tumor size varied between 3.1-16.6 cm. Patients spent an average of 228 min in the MRI suite and sonication with the external transducer lasted an average of 35 min. There were no complications on the day of the MR-HIFU procedure and all acute toxicities (no grade >/=3 toxicities) resolved after completion of treatment. There were no late grade >/=3 toxicities. CONCLUSION: Mild hyperthermia with MR-HIFU, in combination with concurrent chemoradiation for appropriately selected patients, is safe for localized pelvic recurrences from rectal cancer. The potential for MR-HIFU to be applied in the recurrent setting in rectal cancer treatment requires further technical development and prospective evaluation.

Feasibility and safety of left distal trans-radial approach for coronary angiogram and percutaneous coronary intervention in a center in Hong Kong.

INTRODUCTION: The left distal trans-radial approach is not only more convenient for the operator than the conventional left forearm radial approach, it is also more comfortable for right-hand patients during the peri-procedural period. Comparing with conventional approach, it has lower bleeding risk, less pain and lower risk of radial artery occlusion. The aim of this study was to determine the feasibility and the safety of left distal trans-radial approach for coronary angiogram and percutaneous coronary intervention in Hong Kong Chinese who had smaller body built and therefore smaller radial arterial size. METHOD: In this single-center prospective study, 72 patients undergoing elective coronary angiography and/or percutaneous coronary intervention were recruited from August to October 2018. All right-handed patients aged 18 or above undergoing elective procedures during the period were recruited. Exclusion criteria were non-palpable radial arteries, pregnancies, incapability to consent, abnormal Allen's test, and emergency procedures. Sixty patients (42 males, age ranging from 45 to 86 years old) were recruited and underwent the procedures via left distal radial approach. The measurements during access establishment, the procedure details, complications, patients' satisfaction, and arterial occlusion rate were studied. RESULTS: The procedures with left distal radial approach were successful in 51 patients (85%). Crossover rate to conventional right radial approach was 15% (nine patients). Among successful cases, the mean patients' satisfaction was 8.32/10 and the mean pain score was 1.6/10. Post-procedural radial artery occlusion was not encountered. CONCLUSION: Left distal radial approach is a feasible alternative for patients undergoing coronary angiography and/or percutaneous coronary intervention in Hong Kong Chinese patients. It provides good comfortability with minimal pain in right-handed patients. The risk of radial artery occlusion is minimal.

Depression, anxiety, and stress among university students in Selangor, Malaysia during COVID-19 pandemics and their associated factors.

INTRODUCTION: This study aims to assess the impacts of COVID-19 pandemics among university students in Malaysia, by identifying the prevalence of depression, anxiety and stress among them and their respective predictors. METHODOLOGY: An online cross-sectional study was conducted via non-probabilistic convenience sampling. Data were collected on sociodemographic characteristics, lifestyle, COVID-19 related influences. Mental health status was assessed with depression, anxiety, and stress scale (DASS-21). RESULTS: 388 students participated this study (72.4% female; 81.7% Bachelor's student). The prevalence of moderate to severe depression, anxiety and stress among university students are 53.9%, 66.2% and 44.6%, respectively. Multivariable logistic regression analysis found that the odds of depression were lower among students who exercise at least 3 times per week (OR: 0.380, 95% CI: 0.203-0.711). The odd ratio of student who had no personal history of depression to had depression, anxiety and stress during this pandemic was also lower in comparison (OR: 0.489, 95% CI: 0.249-0.962; OR: 0.482, 95% CI: 0.241-0.963; OR: 0.252, 95% CI: 0.111-0.576). Surprisingly, students whose are currently pursuing Master study was associated with lower stress levels (OR: 0.188, 95% CI: 0.053-0.663). However, student who had poorer satisfaction of current learning experience were more likely to experience stress (OR: 1.644, 95% CI: 1.010-2.675). LIMITATIONS: It is impossible to establish causal relationships between variables on mental health outcomes, and there is a risk of information bias. CONCLUSION: The prevalence of mental health issues among university students is high. These findings present essential pieces of predictive information when promoting related awareness among them.

International Validation of the EORTC QLQ-ANL27, a Field Study to Test the Anal Cancer-Specific Health-Related Quality-of-Life Questionnaire.

PURPOSE: The European Organisation for Research and Treatment of Cancer (EORTC) health-related quality of life questionnaire for anal cancer (QLQ-ANL27) supplements the EORTC cancer generic measure (QLQ-C30) to measure concerns specific to people with anal cancer treated with chemoradiotherapy. This study tested the psychometric properties and acceptability of the QLQ-ANL27. METHODS AND MATERIALS: People with anal cancer were recruited from 15 countries to complete the QLQ-C30 and QLQ-ANL27 and provide feedback on the QLQ-ANL27. Item responses, scale structure (multitrait scaling, factor analysis), reliability (internal consistency and reproducibility) and sensitivity (known group comparisons and responsiveness to change) of the QLQ-ANL27 were evaluated. RESULTS: Data from 382 people were included in the analyses. The EORTC QLQ-ANL27 was acceptable, comprehensive, and easy to complete, taking an average 8 minutes to complete. Psychometric analyses supported the EORTC QLQ-ANL27 items and reliability (Cronbach's α ranging from 0.71-0.93 and test-retest coefficients above 0.7) and validity of the scales (particularly nonstoma bowel symptoms and pain/discomfort). Most scales distinguished people according to treatment phase and performance status. Bowel (nonstoma), pain/discomfort, and vaginal symptoms were sensitive to deteriorations over time. The stoma-related scales remained untested because of low numbers of people with a stoma. Revisions to the scoring and question ordering of the sexual items were proposed. CONCLUSIONS: The QLQ-ANL27 has good psychometric properties and is available in 16 languages for people treated with chemoradiotherapy for anal cancer. It is used in clinical trials and has a potential role in clinical practice.

Radiation myelopathy following stereotactic body radiation therapy for spine metastases.

PURPOSE: Stereotactic body radiation therapy (SBRT) is now considered a standard of care treatment option in the management of spine metastases. One of the most feared complications of spine SBRT is radiation myelopathy (RM). METHODS: We provided a narrative review of RM following spine SBRT based on review of the published literature, including data on spinal cord dose constraints associated with the risk of RM, strategies to mitigate the risk, and management options for RM. RESULTS: There are limited published data of cases of RM following spine SBRT with detailed spinal cord dosimetry. The HyTEC report provided recommendations for the point maximal dose (Dmax) for the spinal cord that is associated with a < 5% risk of RM for 1-5 fractions spine SBRT. In the setting of spine SBRT reirradiation after previous conventional external beam radiation therapy (cEBRT), factors associated with RM are: SBRT spinal cord Dmax, cumulative spinal cord Dmax, and the time interval between previous RT and SBRT reirradiation. There are various strategies to mitigate the risk of RM, including accurate delineation of the spinal cord (or thecal sac), strict adherence to the recommended spinal cord dose constraints, and robust treatment immobilisation set-up and delivery. Limited effective treatment options are available for patients who develop RM, and these include corticosteroids, hyperbaric oxygen, and bevacizumab; however, none have been supported by high quality evidence. CONCLUSION: RM is a rare but devastating complication following SBRT for spine metastases. There are strategies to minimise the risk of RM to ensure safe delivery of spine SBRT.

High dose rate brachytherapy in the management of anal cancer: A review.

PURPOSE: To conduct a systematic review evaluating the impact of high dose rate (HDR) brachytherapy (BT) on the clinical outcomes and toxicities of patients with anal cancer. METHODS AND MATERIALS: A search of Medline, Embase, and Cochrane Library databases was performed using search terms: "anal", "anal canal", "squamous", "adenocarcinoma", "cancer", "neoplasm", in combination with "brachytherapy", "high dose rate brachytherapy" or "HDR brachytherapy". Additional studies were identified after scanning references. Studies published in English with ≥10 patients were included. RESULTS: Ten studies (n = 448) were included in this review. 321 patients were treated with curative intent external beam radiotherapy (EBRT), chemotherapy (CT) and HDRBT; of those, 312 and 9 received interstitial and intraluminal BT, respectively. Mean follow up was 39.9 months (range (R): 24-61 months). Complete response was noted between 80%-93% and local control ranged between 81%-88%. Mean rate of local failure was 12.3% (SD 3.6%, R: 8%-18%). Distant failure rate was reported between 2%-3% and metastasis free survival ranged between 82%-88%. Mean disease free survival and overall survival were 77.3% (SD 6.6%, R: 66%-100%) and 82.5% (SD 13.7%, R: 70%-87.7%). Acute toxicity was mostly grade 1/2 dermatitis, proctitis or cystitis; G3 or higher toxicity was reported only in 4 patients in 2 studies (dermatitis n = 3 and sphincter necrosis n = 1). Most common long term toxicities were incontinence (2.5%-9%) and proctitis (2.5%-19%); G3/4 toxicity ranged between 2.2%-7.1%. Mean sphincter preservation rate and colostomy free survival was 88.0% and 80.4%, respectively. CONCLUSION: Pooled analysis in this review suggests excellent response, local control and survival with HDRBT in combination with EBRT and CT, with limited toxicity. Prospective well conducted trials are needed to further establish role of HDRBT management of anal cancer with future focus on development of international consensus on patient selection, dosimetric parameters, treatment sequencing as well as defining uniform outcome and toxicity assessment.

Spatiotemporal Mapping of Early Volume Loss in the Mouse Brain after Cranial Irradiation.

Sequelae after pediatric cranial radiotherapy (CRT) result in long-term changes in brain structure. While past evidence indicates regional differences in brain volume change, it remains unclear how these manifest in the time course of change after CRT. In this study, we spatiotemporally characterized volume losses induced by cranial irradiation in a mouse model, with a dense sampling of measurements over the first week postirradiation. Wild-type mice received whole-brain irradiation (7 Gy) or sham irradiation (0 Gy) at 16 days of age. In vivo magnetic resonance imaging was performed at one time point before, and 2-4 time points postirradiation in each mouse, with a particular focus on sampling during the first week after cranial irradiation. Volume changes across the brain were measured, and the degree and timing of volume loss were quantified across structures from a predefined atlas. Volume measurements across the brain after cranial irradiation revealed a ∼2-day delay in which volume is not significantly altered, after which time volume change proceeds over the course of four days. Volume losses were 3% larger and emerged 40% slower in white matter than in gray matter. Large volume loss was also observed in the ventricles. Differences in the timing and magnitude of volume change between gray and white matter after cranial irradiation were observed. These results suggest differences in the mechanism and/or kinetics underlying the associated radio-response, which may have implications in development.

Round Cell Sarcoma with EWSR1-PATZ1 Fusion in the Face of a Five-Year-Old Boy: Report of a Case with Unusual Histologic Features.

Round cell sarcomas with EWSR1-PATZ1 fusion are rare polyphenotypic sarcomas that typically show both neural and myogenic differentiation on immunohistochemistry. The histology features lobular admixture of cellular fascicles of relatively monotonous spindle cells and small blue round cells separated by fibrotic stroma. The clinical behavior of EWSR1-PATZ1 sarcoma is uncertain currently with mixed outcomes reported even in cases with metastases. We herein report an additional case of EWSR1-PATZ1 fusion-related round cell sarcoma in the face of a 5-year-old boy with unusual histologic features of pale zones, rosette/gland-like structures and expression of epithelial markers. Fluorescent in-situ hybridization study (FISH) using EWSR1 breakapart probes was negative and molecular study with RNA sequencing was required to confirm the diagnosis. These findings highlight the diagnostic challenge and potential pitfall of FISH study in EWSR1-PATZ1 sarcoma. Further studies are required to increase the understanding of their behavior, morphologic spectrum and molecular features that will help devise new treatment strategies to these rare tumours.

Crisis management research (1985-2020) in the hospitality and tourism industry: A review and research agenda.

The global tourism industry has already suffered an enormous loss due to COVID-19 (Coronavirus Disease 2019) in 2020. Crisis management, including disaster management and risk management, has been becoming a hot topic for organisations in the hospitality and tourism industry. This study aims to investigate relevant research domains in the hospitality and tourism industry context. To understand how crisis management practices have been adopted in the industry, the authors reviewed 512 articles including 79 papers on COVID-19, spanning 36 years, between 1985 and 2020. The findings showed that the research focus of crisis management, crisis impact and recovery, as well as risk management, risk perception and disaster management dominated mainstream crisis management research. Look back the past decade (2010 to present), health-related crisis (including COVID-19), social media, political disturbances and terrorism themes are the biggest trends. This paper proposed a new conceptual framework for future research agenda of crisis management in the hospitality and tourism industry. Besides, ten possible further research areas were also suggested in a TCM (theory-context-method) model: the theories of crisis prevention and preparedness, risk communication, crisis management education and training, risk assessment, and crisis events in the contexts of COVID-19, data privacy in hospitality and tourism, political-related crisis events, digital media, and alternative analytical methods and approaches. In addition, specific research questions in these future research areas were also presented in this paper.

Clinical and pathological characterization of FLNC-related myofibrillar myopathy caused by founder variant c.8129G>A in Hong Kong Chinese.

FLNC-related myofibrillar myopathy could manifest as autosomal dominant late-onset slowly progressive proximal muscle weakness; involvements of cardiac and/or respiratory functions are common. We describe 34 patients in nine families of FLNC-related myofibrillar myopathy in Hong Kong ethnic Chinese diagnosed over the last 12 years, in whom the same pathogenic variant c.8129G>A (p.Trp2710*) was detected. Twenty-six patients were symptomatic when diagnosed; four patients died of pneumonia and/or respiratory failure. Abnormal amorphous material or granulofilamentous masses were detected in half of the cases, with mitochondrial abnormalities noted in two-thirds. We also show by haplotype analysis the founder effect associated with this Hong Kong variant, which might have occurred 42 to 71 generations ago or around Tang and Song dynasties, and underlain a higher incidence of myofibrillar myopathy among Hong Kong Chinese. The late-onset nature and slowly progressive course of the highly penetrant condition could have significant impact on the family members, and an early diagnosis could benefit the whole family. Considering another neighboring founder variant in FLNC in German patients, we advocate development of specific therapies such as chaperone-based or antisense oligonucleotide strategies for this particular type of myopathy.

Outcomes of extra-cranial stereotactic body radiotherapy for metastatic colorectal cancer: Dose and site of metastases matter.

BACKGROUND AND PURPOSE: To review the clinical outcomes following the use of stereotactic body radiotherapy (SBRT) in patients with metastatic colorectal cancer (mCRC) from a large academic institution. MATERIALS AND METHODS: Patients with mCRC treated with extracranial SBRT between 2008 and 2016 were identified from an institutional database. Treatment indications were oligometastases, oligoprogression, and local control of dominant tumors. Endpoints included local progression (LP), overall survival (OS), progression-free survival (PFS), and cumulative incidence of starting or changing systemic therapy (SCST). Univariate and multivariable analyses (MVA) were performed to identify predictive factors. RESULTS: One hundred and sixty-five patients (262 lesions treated) were included. The 2-year cumulative incidence of LP was 23.8%. Lower SBRT doses and tumor location in the liver were significant predictors of LP on MVA. Median OS was 49.3 months, 19.3 months, and 9.0 months for oligometastases, oligoprogression, and local control of dominant tumors, respectively. Primary tumor not in situ, smaller tumors, fewer lines of previous systemic therapy, lower CEA, and oligometastases treatment indications were significant predictors of higher OS on MVA. For the entire cohort, median PFS was 9.9 months, while oligometastatic patients had a median PFS of 12.4 months. 2-year cumulative incidence of SCST was 41.7%. CONCLUSIONS: Survival outcomes are favorable after SBRT for mCRC patients. A significant proportion of patients did not have a change in systemic therapy after SBRT. Higher doses are required to obtain the best local control. Efforts should be made to better optimize SBRT delivery for liver metastases given their higher local failure rate.

Flexi-Myo Panel Strategy: Genomic Diagnoses of Myopathies and Muscular Dystrophies by Next-Generation Sequencing.

Aims: Muscle disorders are clinically and genetically heterogeneous. Investigations, including plasma creatine kinase, electromyography, and nerve conduction velocity studies are often nonspecific, whereas muscle biopsy might be limited by sampling bias and variable histopathology. Next-generation sequencing is now generally considered an important diagnostic tool for muscle disorders, with decreased costs and improved diagnostic yield. Inclusion of a large number of genes in the analysis might, however, generate a large number of ambiguous results and create unnecessary confusion for clinicians and patients. Methods: An ethnic Chinese patient presented at age 10 with tip-toe walking. Upon examination the patient had a waddling gait, a tight Achilles tendon with pes cavus. A muscle biopsy showed the presence of minicores with disruption of the myofibrillary network and Z-bands. Sequencing was performed using the Flexi-Myo panel, which provides coverage for 85 myopathic genes. Reporting of sequencing results was decided by the responsible chemical pathologists based on the available clinical and genetic information. Results: A previously identified heterozygous in-frame deletion was detected in MYH7, which confirmed the diagnosis of Laing myopathy. No variants of uncertain significance required reporting. Conclusion: We describe the effectiveness of our Flexi-Myo panel approach for the diagnosis of muscle disorders, which confirmed diagnosis of Laing myopathy in what had been a clinically ambiguous presentation. This approach enables efficient genomic testing for muscle diseases in adults and children with satisfactory diagnostic yield and sufficient sensitivity, whereas avoiding the reporting of ambiguous results. Similar strategies might also be implemented for other groups of disorders.

Founder Mutation c.1516A>C in KLHL40 Is a Frequent Cause of Nemaline Myopathy With Hyponatremia in Ethnic Chinese.

KLHL40-related nemaline myopathy is a severe autosomal recessive muscle disorder. The current study describes 4 cases of KLHL40-related nemaline myopathy in Hong Kong ethnic Chinese presenting within 3 years, which are confirmed with clinicopathologic features and genetic studies. The incidence is estimated to be at least 1 in 45 226 livebirths (at least 1 in 41 608 among ethnic Chinese livebirths) in Hong Kong. Hyponatremia appears to be another common feature in these patients. Salient histological features include nemaline bodies ranging from 200 to 500 nm in diameters on ultrastructural examination as well as negative KLHL40 immunohistochemistry; type II fiber predominance is obvious in 2 cases. We demonstrate the founder effect associated with genetic variant c.1516A>C (p.Thr506Pro) by polymorphic marker analysis, which revealed a 0.56-0.75-Mb or 0.41-0.78-cM shared haplotype encompassing the disease allele. The mutation is believed to have occurred around 412 generations ago or 6220 BCE, as estimated using DMLE+ and a formula described by Boehnke. We believe the founder variant might possibly underlie a sizable portion of nemaline myopathy in ethnic Chinese. Analysis of the KLHL40 gene may be considered as the first-tier testing of congenital myopathy in this ethnic group.

A Humanist Neurosurgeon: A Legacy of Dr. Roy Selby.

The article is dedicated to the life and work of Dr. Roy Selby (1930-2002), an American neurosurgeon who founded neurosurgery in Malaysia. Dr. Selby stayed in Malaysia from July 1963 to May 1970. He opened the first neurosurgical department at the general hospital in Kuala Lumpur and established a training program under which Malaysian physicians and nurses were sent to neurosurgery centers in the United States and Canada. Some physicians came back and headed local neurosurgical units. On his return to the United States, Dr. Selby practiced neurosurgery until 1986, when he had to give it up due to the impact of progressive congestive heart failure. From 1986 to 1994, Dr. Selby taught graduate courses in the Department of Psychology at East Texas State University, Texarkana, Texas. He was a pioneer of spinal surgery and founded the Lumbar Spine Society. Dr. Selby was a world citizen neurosurgeon and advocated international standards of training in neurosurgery. From 1985 to 1994, he was chairman of the Archives Committee of the American Association of Neurological Surgeons. Dr. Selby serves as a model of a physician as a humanist.

Synchronous anal canal carcinoma in a heterosexual couple.

BACKGROUND: Sexually transmitted Human Papilloma Virus (HPV) infection is a known risk factor for cancer of the anal canal in both men and women. CASE PRESENTATION: We describe a report of synchronous carcinoma of the anal canal in a heterosexual couple. High risk type 16 HPV DNA was detected in both tumors. CONCLUSION: Longstanding sexual partners may share risk of HPV-associated anal canal cancer.

Mapping the contribution and strategic distribution patterns of neuroimaging features of small vessel disease in poststroke cognitive impairment.

OBJECTIVES: Individual neuroimaging features of small vessel disease (SVD) have been reported to influence poststroke cognition. This study aimed to investigate the joint contribution and strategic distribution patterns of multiple types of SVD imaging features in poststroke cognitive impairment. METHODS: We studied 145 first-ever ischaemic stroke patients with MRI and Montreal Cognitive Assessment (MoCA) examined at baseline. The local burdens of acute ischaemic lesion (AIL), white matter hyperintensity, lacune, enlarged perivascular space and cross-sectional atrophy were quantified and entered into support vector regression (SVR) models to associate with the global and domain scores of MoCA. The SVR models were optimised with feature selection through 10-fold cross-validations. The contribution of SVD features to MoCA scores was measured by the prediction accuracy in the corresponding SVR model after optimisation. RESULTS: The combination of the neuroimaging features of SVD contributed much more to the MoCA deficits on top of AILs compared with individual SVD features, and the cognitive impact of different individual SVD features was generally similar. As identified by the optimal SVR models, the important SVD-affected regions were mainly located in the basal ganglia and white matter around it, although the specific regions varied for MoCA and its domains. CONCLUSIONS: Multiple types of SVD neuroimaging features jointly had a significant impact on global and domain cognitive functionings after stroke on top of AILs. The map of strategic cognitive-relevant regions of SVD features may help clinicians to understand their complementary impact on poststroke cognition.

The effect of prone and supine treatment positions for the pre-operative treatment of rectal cancer on organ-at-risk sparing and setup reproducibility using volumetric modulated arc therapy.

BACKGROUND AND PURPOSE: To compare organ-at-risk doses and setup reproducibility using the prone and supine orientations in volumetric modulated arc therapy (VMAT) for rectal cancer. MATERIALS AND METHODS: Seventeen consecutive rectal cancer patients undergoing preoperative radiation were selected and setup in either the prone (N = 8) or supine (N = 9) position. All patients were treated using posteriorly-applied VMAT. Bladder and small bowel dose and cone beam CT (CBCT) reproducibility metrics were retrospectively collected. RESULTS: Dose metrics for bladder and small bowel did not show significant differences between the prone and supine orientations. The prone data had a trend for smaller irradiated volumes than supine for the small bowel at lower doses-V20 (prone: 135 ± 99 cm3; supine: 201 ± 162 cm3) and V30 (prone: 78 ± 71 cm3; supine: 105 ± 106 cm3). At higher doses, the trend reversed as exemplified by the small bowel V50.4 (prone: 20 ± 28 cm3; supine: 10 ± 14 cm3). CBCT data showed that rotational errors in pitch and roll were significantly larger for the prone vs. supine orientation (pitch: 2.0° ± 1.3° vs. 0.8° ± 1.1° p < 0.001; roll: 1.0° ± 0.9° vs. 0.3° ± 0.5°, p < 0.001). CONCLUSIONS: Bladder and small bowel doses were not significantly different when comparing VMAT plans developed for the prone and supine orientations. The supine orientation demonstrated improved setup reproducibility.

Catalytic Direct C2-Alkenylation of Oxazoles at Parts per Million Levels of Palladium/PhMezole-Phos Complex.

General direct C2-alkenylation of oxazoles is reported using alkenyl tosylates at parts per million levels of palladium catalyst. From a series of ligands screened, PhMezole-Phos emerged as the promising ligand candidate to facilitate this reaction. Significantly, the method is scalable and exhibits excellent substrate tolerance. Highly sterically hindered substrates and small vinyl tosylate can be coupled successfully. Moreover, our method enables a rapid diversification of oxazole-based C^N ligands which can be readily derived into new group 9 organometallic compounds.

Differential Apoptosis Radiosensitivity of Neural Progenitors in Adult Mouse Hippocampus.

Mammalian tissue-specific stem cells and progenitors demonstrate differential DNA damage response. Neural progenitors in dentate gyrus of the hippocampus are known to undergo apoptosis after irradiation. Using a mouse model of hippocampal neuronal development, we characterized the apoptosis sensitivity of the different neural progenitor subpopulations in adult mouse dentate gyrus after irradiation. Two different bromodeoxyuridine incorporation paradigms were used for cell fate mapping. We identified two apoptosis sensitive neural progenitor subpopulations after irradiation. The first represented non-proliferative and non-newborn neuroblasts and immature neurons that expressed doublecortin, calretinin or both. The second consisted of proliferative intermediate neural progenitors. The putative radial glia-like neural stem cells or type-1 cells, regardless of proliferation status, were apoptosis resistant after irradiation. There was no evidence of radiation-induced apoptosis in the absence of the Trp53 (p53) gene but absence of Cdkn1a (p21) did not alter the apoptotic response. Upregulation of nuclear p53 was observed in neuroblasts after irradiation. We conclude that adult hippocampal neural progenitors may demonstrate differential p53-dependent apoptosis sensitivity after irradiation.

A novel prospective descriptive analysis of nausea and vomiting among patients receiving gastrointestinal radiation therapy.

PURPOSE: Nausea and vomiting are common side effects from radiotherapy that can interfere with gastrointestinal (GI) cancer patients' quality of life (QOL). This study described the subjective experience of patients with radiation-induced nausea and vomiting (RINV) and its relation to QOL. METHODS: Forty-eight patients treated with abdominal radiotherapy alone or with concomitant chemoradiotherapy were followed in a prospective study. All episodes of nausea, vomiting, and antiemetic use were recorded daily for the treatment period and the week following completion of therapy. QOL was assessed weekly using the Functional Living Index-Emesis QOL Tool (FLIE) and the EORTC QLQ-C30 core questionnaire (C30). RESULTS: In total, 351 episodes of nausea severity, duration, onset time, and 154 outcomes of vomiting onset times and contents were documented. The median nausea severity experienced per episode was 5 (on a scale from 1 to 10), and the most common durations of nausea were 30 min or less and constant nausea all day and night. The most common location of nausea was the abdomen. Longer nausea duration, great nausea severities, and the location of nausea experienced had significant adverse relationships to multiple QOL items on both the FLIE and the C30. In addition, the onset timing and number of vomiting episodes were related to the majority of all FLIE and QOL scores. CONCLUSION: Patient's subjective experiences of RINV directly correlated to the worsening of QOL outcomes. The identification and amelioration of these RINV experiences could improve QOL.