c-Myc induces chromosomal rearrangements through telomere and chromosome remodeling in the interphase nucleus

In previous work, we showed that telomeres of normal cells are organized within the 3D space of the interphase nucleus in a nonoverlapping and cell cycle-dependent manner. This order is distorted in tumor cell nuclei where telomeres are found in close association forming aggregates of various numbers and sizes. Here we show that c-Myc overexpression induces telomeric aggregations in the interphase nucleus. Directly proportional to the duration of c-Myc deregulation, we observe three or five cycles of telomeric aggregate formation in interphase nuclei. These cycles reflect the onset and propagation of breakage-bridge-fusion cycles that are initiated by end-to-end telomeric fusions of chromosomes. Subsequent to initial chromosomal breakages, new fusions follow and the breakage-bridge-fusion cycles continue. During this time, nonreciprocal translocations are generated. c-Myc-dependent remodeling of the organization of telomeres thus precedes the onset of genomic instability and subsequently leads to chromosomal rearrangements. Our findings reveal that c-Myc possesses the ability to structurally modify chromosomes through telomeric fusions, thereby reorganizing the genetic information.     

Non‐total body irradiation myeloablative conditioning with intravenous busulfan and cyclophosphamide in hematopoietic stem cell transplantation for malignant infantile osteopetrosis

HSCT is the only curative treatment for MIOP. We prospectively investigated the outcome of HSCT using intravenous busulfan‐based conditioning regimen from 2008 to 2013. Nineteen patients (median age = 17 months) underwent transplantation from HLA‐matched related donors (n = 14), HLA‐haploidentical related donors (n = 2), partially matched cord blood donors (n = 2), and HLA‐matched unrelated donor (n = 1). Bone marrow (n = 9), peripheral blood (n = 8), and cord blood (n = 2) were used as stem cell sources. All but one patient demonstrated primary engraftment. Two patients experienced secondary graft failure. During the follow‐up period, three patients showed mixed chimerism (45%, 45%, and 70% of donor cells were engrafted in each one of these patients) but are disease free. Two‐yr OS and DFS were 84.2% and 73.7%, respectively. Improvement of visual acuity and partial reversal of mild conductive hearing loss occurred in two and four patients, respectively. The causes of death among three patients were infection, GvHD, and disease progression. In conclusion, due to major side effects of MIOP such as visual and hearing loss, early treatment using myeloablative conditioning without irradiation HSCT is suggested. The use of an HLA‐matched related donor seems to be highly successful in this regard. Also, according to results of our study, mixed chimerism may be sufficient to resolve symptoms of disease.     

Single-molecule selection and recovery of structure-specific antibodies using atomic force microscopy

Protein misfolding and aggregation are a common thread in numerous diseases including Alzheimer's, Parkinson's, Huntington's, amyotrophic lateral sclerosis, diabetes, and prion-related diseases. Elucidation of the role played by the various protein forms in these diseases requires reagents that can target specific protein forms. Here we present a method to isolate antibodies that bind to a specific protein form. We combined the imaging and nanomanipulation capabilities of atomic force microscopy (AFM) with the protein diversity of phage display antibody libraries to develop a technology that allows us to recover a single antibody molecule that is bound to a single protein molecular target. The target protein-antibody complex is first imaged by AFM, the AFM tip is then manipulated by nanolithography over the target antibody to recover the associated phage, and the antibody gene is recovered from the single phage particle by polymerase chain reaction.     

Predictors of competing mortality to invasive breast cancer incidence in the Canadian National Breast Screening study

ABSTRACT: BACKGROUND: Evaluating the cost-effectiveness of breast cancer screening requires estimates of the absolute risk of breast cancer, which is modified by various risk factors. Breast cancer incidence, and thus mortality, is altered by the occurrence of competing events. More accurate estimates of competing risks should improve the estimation of absolute risk of breast cancer and benefit from breast cancer screening, leading to more effective preventive, diagnostic, and treatment policies. We have previously described the effect of breast cancer risk factors on breast cancer incidence in the presence of competing risks. In this study, we investigate the association of the same risk factors with mortality as a competing event with breast cancer incidence. METHODS: We use data from the Canadian National Breast Screening Study, consisting of two randomized controlled trials, which included data on 39 risk factors for breast cancer. The participants were followed up for the incidence of breast cancer and mortality due to breast cancer and other causes. We stratified all-cause mortality into death from other types of cancer and death from non-cancer causes. We conducted separate analyses for cause-specific mortalities. RESULTS: We found that "age at entry" is a significant factor for all-cause mortality, and cancer-specific and non-cancer mortality. "Menstruation length" and "number of live births" are significant factors for all-cause mortality, and cancer-specific mortality. "Ever noted lumps in right/left breasts" is a factor associated with all-cause mortality, and non-cancer mortality. CONCLUSIONS: For proper estimation of absolute risk of the main event of interest common risk factors associated with competing events should be identified and considered.     

Incidence of invasive breast cancer in the presence of competing mortality: the Canadian National Breast Screening Study

Mortality due to causes other than breast cancer is a potential competing risk which may alter the incidence probability of breast cancer and as such should be taken into account in predictive modelling. We used data from the Canadian National Breast Screening Study (CNBSS), which consist of two randomized controlled trials designed to evaluate the efficacy of mammography among women aged 40-59. The participants in the CNBSS were followed up for incidence of breast cancer and mortality due to breast cancer and other causes; this allowed us to construct a breast cancer risk prediction model while taking into account mortality for the same study population. In this study, we use 1980-1989 as the study period. We exclude the prevalent cancers from the CNBSS to estimate the probability of developing breast cancer, given the fact that women were cancer-free at the beginning of the follow-up. By the end of 1989, from 89,434 women, 944 (1.1 %) were diagnosed with invasive breast cancer, 922 (1.0 %) died from causes other than breast cancer, and 87,568 (97.9 %) were alive and not diagnosed with invasive breast cancer. We constructed a risk prediction model for invasive breast cancer based on 39 risk factors collected at the time of enrolment or the initial physical examination of the breasts. Age at entry (HR 1.07, 95 % CI 1.05-1.10), lumps ever found in left or right breast (HR 1.92, 95 % CI 1.19-3.10), abnormality in the left breast (HR 1.26, 95 % CI 1.07-1.48), history of other breast disease, family history of breast cancer score (HR 1.01, 95 % CI 1.00-1.01), years menstruating (HR 1.02, 95 % CI 1.01-1.03) and nulliparity (HR 1.70, 95 % CI 1.23-2.36) are the model's predictors. We investigated the effects of time-dependent factors. The model is well calibrated with a moderate discriminatory power (c-index 0.61, 95 % CI 0.59-0.63); we use it to predict the 9-year risk of developing breast cancer for women of different age groups. As an example, we estimated the probability of invasive cancer at 5 years after enrolment to be 0.00448, 0.00556, 0.00691, 0.00863, and 0.01034, respectively, for women aged 40, 45, 50, 55, and 59, all of whom had never noted lumps in their breasts, had 32 years of menstruating, 1-2 live births, no other types of breast disease and no abnormality found in their left breasts. The results of this study can be used by clinicians to identify women at high risk of breast cancer for screening intervention and to recommend a personalized intervention plan. The model can be also utilized by a woman as a breast cancer risk prediction tool.     

The Health of Female Iranian Immigrants in Sweden: A Qualitative Six-Year Follow-Up Study

Immigration affects life and health in many different ways. The purpose of this study was to identify and analyze female Iranian immigrants’ perception of various factors that influence their health over time. Data collection was based on semistructured interviews with 10 female Iranian immigrants. Baseline interviews were conducted in 1996, with follow-up interviews in 2002. The results suggest that during the first decade after migration, female immigrants may overcome some health-related factors such as experiences of traumatic events. Other health determinants such as unemployment or experiences of discrimination and racism, however, were observed even two decades after migration.     

McConnell's sign: Echocardiography in the management of acute pulmonary embolism

Management of acute pulmonary embolism depends immensely on rapid diagnosis and early intervention. Transthoracic echocardiography has gained favorability in scenarios where diagnostic computed tomography angiography is not feasible. McConnell''s sign, an echocardiographic finding of segmental right ventricular wall‐motion abnormality with apical sparing, is highly specific and may guide therapeutic intervention. We present the case of a 59‐year‐old man who was found to have acute pulmonary embolism with obstructive shock, managed successfully with thrombolytic therapy after identification of McConnell''s sign. We review current literature and develop a framework for the integration of echocardiography into the multimodal approach to management.     

Probiotic yogurt consumption may improve gastrointestinal symptoms,productivity, and nutritional intake of people living with human immunodeficiency virus in Mwanza,Tanzania

The gut-associated lymphoid tissue is a major site of human immunodeficiency virus (HIV) activity and significantly influences disease prognosis. Reducing immune activation due to gastroenteritis may thus help slow disease progression. Probiotic microorganisms have considerable immunomodulatory effects at the level of the gut-associated lymphoid tissue. A probiotic yogurt initiative was thus established in Mwanza, Tanzania, to improve gastrointestinal (GI) integrity and reduce the incidence and severity of opportunistic infections among people with HIV. The research objective was to retrospectively evaluate the effects of yogurt supplemented with Lactobacillus rhamnosus as an adjunct to the diet of people living with HIV on systemic and GI symptoms, daily routine activities, and nutritional intake. Eighty-five people with HIV consuming probiotic yogurt and 86 controls were interviewed. Demographics and HIV disease stage were comparable between groups. Probiotic yogurt consumers reported an ability to work a median of 2 hours more daily (P = .01), experienced a lower fever incidence (P = .01), and were more likely to achieve daily nutrient requirements for vitamin A, several B complex vitamins, and calcium (P = .02). Antiretroviral users experienced less drug-induced stomach pain (P = .02) and a lower overall impact of GI symptoms on routine activities (P = .03). The results of this study need be further substantiated because of limits imposed by the observational, retrospective study design; however, results suggest that yogurt supplemented with L rhamnosus may effectively alleviate GI symptoms and improve productivity, nutritional intake, and tolerance to antiretroviral treatment among people with HIV in Mwanza.     

Patient and Patient Group Engagement in Cancer Clinical Trials: A Stakeholder Charter

Background—to guide the implementation of patient centricity and engagement in cancer clinical trials (CTs) and to operationalize the Canadianized version of the Clinical Trials Transformation Initiative (C-CTTI) model, the development of a charter was identified by cancer CT stakeholders. Methods—the Canadian Cancer Trial Stakeholder Charter (the Charter) was initiated by Colorectal Cancer Canada (CCC) and developed via the—1—formation of an inclusive working group (WG) that drafted the document using recommendations collected during the development of the C-CTTI model; 2—socialization of the draft Charter to solicit feedback from cancer CT stakeholders, including those who attended the 2019 CCC Conference; and 3—incorporation of stakeholders’ feedback and finalization of the Charter by the WG. Results—the Charter was built around five guiding principles—1—patient centricity; 2—commitment to education and training; 3—collaboration as equal and independent partners in research; 4—transparency and accountability; and 5—high standards in data collection integrity and honesty. These principles led to the Charter’s five tenets, which stipulate stakeholder commitments, aiming to make CTs accessible to all patients, improve the design and implementation of CTs to benefit patients, expand recruitment and retention of patients in CTs, and further advance cancer research and treatment. Conclusions—the Charter is intended to integrate the patient voice into the Canadian cancer CT continuum. The next phases of the C-CTTI model include the adoption and implementation of the Charter, the establishment of a patient group training program, and the development of real-world evidence/real-world data methodologies.