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  1. Article ; Online: Shape-specific characterization of colorectal adenoma growth and transition to cancer with stochastic cell-based models.

    Simonetto, Cristoforo / Mansmann, Ulrich / Kaiser, Jan Christian

    PLoS computational biology

    2023  Volume 19, Issue 1, Page(s) e1010831

    Abstract: Colorectal adenoma are precursor lesions on the pathway to cancer. Their removal in screening colonoscopies has markedly reduced rates of cancer incidence and death. Generic models of adenoma growth and transition to cancer can guide the implementation ... ...

    Abstract Colorectal adenoma are precursor lesions on the pathway to cancer. Their removal in screening colonoscopies has markedly reduced rates of cancer incidence and death. Generic models of adenoma growth and transition to cancer can guide the implementation of screening strategies. But adenoma shape has rarely featured as a relevant risk factor. Against this backdrop we aim to demonstrate that shape influences growth dynamics and cancer risk. Stochastic cell-based models are applied to a data set of 197,347 Bavarian outpatients who had colonoscopies from 2006-2009, 50,649 patients were reported with adenoma and 296 patients had cancer. For multi-stage clonal expansion (MSCE) models with up to three initiating stages parameters were estimated by fits to data sets of all shapes combined, and of sessile (70% of all adenoma), peduncular (17%) and flat (13%) adenoma separately for both sexes. Pertinent features of adenoma growth present themselves in contrast to previous assumptions. Stem cells with initial molecular changes residing in early adenoma predominantly multiply within two-dimensional structures such as crypts. For these cells mutation and division rates decrease with age. The absolute number of initiated cells in an adenoma of size 1 cm is small around 103, related to all bulk cells they constitute a share of about 10-5. The notion of very few proliferating stem cells with age-decreasing division rates is supported by cell marker experiments. The probability for adenoma transiting to cancer increases with squared linear size and shows a shape dependence. Compared to peduncular and flat adenoma, it is twice as high for sessile adenoma of the same size. We present a simple mathematical expression for the hazard ratio of interval cancers which provides a mechanistic understanding of this important quality indicator. We conclude that adenoma shape deserves closer consideration in screening strategies and as risk factor for transition to cancer.
    MeSH term(s) Male ; Female ; Humans ; Colorectal Neoplasms/pathology ; Colonoscopy/methods ; Risk Factors ; Incidence ; Adenoma/diagnosis
    Language English
    Publishing date 2023-01-23
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2193340-6
    ISSN 1553-7358 ; 1553-734X
    ISSN (online) 1553-7358
    ISSN 1553-734X
    DOI 10.1371/journal.pcbi.1010831
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Eine naturalistische Untersuchung zur Auswirkung häufiger antidepressiver Medikationen (wie SSRI) und der Acetylsalicylsäure (ASS) auf die Selbstbeurteilungen der Wahrnehmung und des Ergebnisses stationärer Psychotherapie: Könnte ASS förderlich sein?

    Binneböse, Marius / Schott, Jan / Wallis, Hannah / Kaiser, Christian / Vogel, Matthias

    Zeitschrift fur Psychosomatische Medizin und Psychotherapie

    2023  Volume 69, Issue 4, Page(s) 369–382

    Abstract: Objectives: ...

    Title translation A naturalistic study on the effects of antidepressants (e. g. SSRI) and acetyl salicylic acid (ASA) on the self-rated perception of the psychotherapeutic process of inpatient psychosomatic treatment and its results: Could ASA be beneficial?
    Abstract Objectives:
    MeSH term(s) Humans ; Aspirin/adverse effects ; Salicylic Acid ; Amitriptyline/adverse effects ; Inpatients ; Antidepressive Agents/adverse effects ; Psychophysiologic Disorders ; Psychotherapeutic Processes ; Perception
    Chemical Substances Aspirin (R16CO5Y76E) ; Salicylic Acid (O414PZ4LPZ) ; Amitriptyline (1806D8D52K) ; Antidepressive Agents
    Language German
    Publishing date 2023-12-27
    Publishing country Germany
    Document type English Abstract ; Journal Article
    ZDB-ID 1462944-6
    ISSN 1438-3608
    ISSN 1438-3608
    DOI 10.13109/zptm.2023.69.4.369
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Socioeconomic correlates of SARS-CoV-2 and influenza H1N1 outbreaks.

    Kaiser, Jan Christian / Stathopoulos, Georgios T

    The European respiratory journal

    2020  Volume 56, Issue 3

    MeSH term(s) Betacoronavirus ; COVID-19 ; Coronavirus Infections/epidemiology ; Coronavirus Infections/mortality ; Disease Outbreaks ; Gross Domestic Product ; Health Expenditures ; Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human/epidemiology ; Influenza, Human/mortality ; Linear Models ; Pandemics ; Pneumonia, Viral/epidemiology ; Pneumonia, Viral/mortality ; Population Density ; Regression Analysis ; Risk Factors ; SARS-CoV-2 ; Socioeconomic Factors ; Urbanization
    Keywords covid19
    Language English
    Publishing date 2020-09-17
    Publishing country England
    Document type Letter
    ZDB-ID 639359-7
    ISSN 1399-3003 ; 0903-1936
    ISSN (online) 1399-3003
    ISSN 0903-1936
    DOI 10.1183/13993003.01400-2020
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Simonetto et al. Respond to "Mechanistic Models in Epidemiology".

    Simonetto, Cristoforo / Heier, Margit / Peters, Annette / Kaiser, Jan Christian / Rospleszcz, Susanne

    American journal of epidemiology

    2022  Volume 191, Issue 10, Page(s) 1781–1782

    Language English
    Publishing date 2022-06-02
    Publishing country United States
    Document type Journal Article ; Comment
    ZDB-ID 2937-3
    ISSN 1476-6256 ; 0002-9262
    ISSN (online) 1476-6256
    ISSN 0002-9262
    DOI 10.1093/aje/kwac100
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Concepts of association between cancer and ionising radiation: accounting for specific biological mechanisms.

    Eidemüller, Markus / Becker, Janine / Kaiser, Jan Christian / Ulanowski, Alexander / Apostoaei, A Iulian / Hoffman, F Owen

    Radiation and environmental biophysics

    2023  Volume 62, Issue 1, Page(s) 1–15

    Abstract: The probability that an observed cancer was caused by radiation exposure is usually estimated using cancer rates and risk models from radioepidemiological cohorts and is called assigned share (AS). This definition implicitly assumes that an ongoing ... ...

    Abstract The probability that an observed cancer was caused by radiation exposure is usually estimated using cancer rates and risk models from radioepidemiological cohorts and is called assigned share (AS). This definition implicitly assumes that an ongoing carcinogenic process is unaffected by the studied radiation exposure. However, there is strong evidence that radiation can also accelerate an existing clonal development towards cancer. In this work, we define different association measures that an observed cancer was newly induced, accelerated, or retarded. The measures were quantified exemplarily by Monte Carlo simulations that track the development of individual cells. Three biologically based two-stage clonal expansion (TSCE) models were applied. In the first model, radiation initiates cancer development, while in the other two, radiation has a promoting effect, i.e. radiation accelerates the clonal expansion of pre-cancerous cells. The parameters of the TSCE models were derived from breast cancer data from the atomic bomb survivors of Hiroshima and Nagasaki. For exposure at age 30, all three models resulted in similar estimates of AS at age 60. For the initiation model, estimates of association were nearly identical to AS. However, for the promotion models, the cancerous clonal development was frequently accelerated towards younger ages, resulting in associations substantially higher than AS. This work shows that the association between a given cancer and exposure in an affected person depends on the underlying biological mechanism and can be substantially larger than the AS derived from classic radioepidemiology.
    MeSH term(s) Humans ; Adult ; Middle Aged ; Neoplasms, Radiation-Induced/epidemiology ; Neoplasms, Radiation-Induced/etiology ; Nuclear Warfare ; Models, Biological ; Carcinogenesis ; Radiation, Ionizing ; Japan
    Language English
    Publishing date 2023-01-12
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 124987-3
    ISSN 1432-2099 ; 0301-634X
    ISSN (online) 1432-2099
    ISSN 0301-634X
    DOI 10.1007/s00411-022-01012-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Heterogeneity in coronary heart disease risk.

    Simonetto, Cristoforo / Rospleszcz, Susanne / Kaiser, Jan Christian / Furukawa, Kyoji

    Scientific reports

    2022  Volume 12, Issue 1, Page(s) 10131

    Abstract: There is large inter-individual heterogeneity in risk of coronary heart disease (CHD). Risk factors traditionally used in primary risk assessment only partially explain this heterogeneity. Residual, unobserved heterogeneity leads to age-related ... ...

    Abstract There is large inter-individual heterogeneity in risk of coronary heart disease (CHD). Risk factors traditionally used in primary risk assessment only partially explain this heterogeneity. Residual, unobserved heterogeneity leads to age-related attenuation of hazard rates and underestimation of hazard ratios. Its magnitude is unknown. Therefore, we aimed to estimate a lower and an approximate upper bound. Heterogeneity was parametrized by a log-normal distribution with shape parameter σ. Analysis was based on published data. From concordance indices of studies including traditional risk factors and additional diagnostic imaging data, we calculated the part of heterogeneity explained by imaging data. For traditional risk assessment, this part typically remains unexplained, thus constituting a lower bound on unobserved heterogeneity. Next, the potential impact of heterogeneity on CHD hazard rates in several large countries was investigated. CHD rates increase with age but the increase attenuates with age. Presuming this attenuation to be largely caused by heterogeneity, an approximate upper bound on σ was derived. Taking together both bounds, unobserved heterogeneity in studies without imaging information can be described by a shape parameter in the range σ = 1-2. It substantially contributes to observed age-dependences of hazard ratios and may lead to underestimation of hazard ratios by a factor of about two. Therefore, analysis of studies for primary CHD risk assessment should account for unobserved heterogeneity.
    MeSH term(s) Coronary Disease/epidemiology ; Coronary Disease/etiology ; Humans ; Proportional Hazards Models ; Risk Assessment ; Risk Factors
    Language English
    Publishing date 2022-06-16
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-14013-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Simultaneous Inside and Outside Functionalization of Single-Walled Carbon Nanotubes.

    Kraus, Jan / Meingast, Laura / Hald, Janina / Beil, Sebastian B / Biskupek, Johannes / Ritterhoff, Christian L / Gsänger, Sebastian / Eisenkolb, Jasmin / Meyer, Bernd / Kaiser, Ute / Maultzsch, Janina / von Delius, Max

    Angewandte Chemie (International ed. in English)

    2024  , Page(s) e202402417

    Abstract: Functionalizing single-walled carbon nanotubes (SWCNTs) in a robust way that does not affect the ... ...

    Abstract Functionalizing single-walled carbon nanotubes (SWCNTs) in a robust way that does not affect the sp
    Language English
    Publishing date 2024-03-15
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202402417
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Biologically based models of cancer risk in radiation research.

    Kaiser, Jan Christian / Blettner, Maria / Stathopoulos, Georgios T

    International journal of radiation biology

    2020  Volume 97, Issue 1, Page(s) 2–11

    MeSH term(s) Biomarkers ; Databases, Factual ; Humans ; Models, Biological ; Neoplasms, Radiation-Induced/etiology ; Radiation Dosage ; Radiation Protection ; Research Design ; Risk Assessment
    Chemical Substances Biomarkers
    Language English
    Publishing date 2020-07-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 3065-x
    ISSN 1362-3095 ; 0020-7616 ; 0955-3002
    ISSN (online) 1362-3095
    ISSN 0020-7616 ; 0955-3002
    DOI 10.1080/09553002.2020.1784490
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Heterogeneity in coronary heart disease risk

    Cristoforo Simonetto / Susanne Rospleszcz / Jan Christian Kaiser / Kyoji Furukawa

    Scientific Reports, Vol 12, Iss 1, Pp 1-

    2022  Volume 9

    Abstract: Abstract There is large inter-individual heterogeneity in risk of coronary heart disease (CHD). Risk factors traditionally used in primary risk assessment only partially explain this heterogeneity. Residual, unobserved heterogeneity leads to age-related ... ...

    Abstract Abstract There is large inter-individual heterogeneity in risk of coronary heart disease (CHD). Risk factors traditionally used in primary risk assessment only partially explain this heterogeneity. Residual, unobserved heterogeneity leads to age-related attenuation of hazard rates and underestimation of hazard ratios. Its magnitude is unknown. Therefore, we aimed to estimate a lower and an approximate upper bound. Heterogeneity was parametrized by a log-normal distribution with shape parameter σ. Analysis was based on published data. From concordance indices of studies including traditional risk factors and additional diagnostic imaging data, we calculated the part of heterogeneity explained by imaging data. For traditional risk assessment, this part typically remains unexplained, thus constituting a lower bound on unobserved heterogeneity. Next, the potential impact of heterogeneity on CHD hazard rates in several large countries was investigated. CHD rates increase with age but the increase attenuates with age. Presuming this attenuation to be largely caused by heterogeneity, an approximate upper bound on σ was derived. Taking together both bounds, unobserved heterogeneity in studies without imaging information can be described by a shape parameter in the range σ = 1–2. It substantially contributes to observed age-dependences of hazard ratios and may lead to underestimation of hazard ratios by a factor of about two. Therefore, analysis of studies for primary CHD risk assessment should account for unobserved heterogeneity.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2022-06-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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