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  1. Article ; Online: Firing statistics in the bistable regime of neurons with homoclinic spike generation.

    Schleimer, Jan-Hendrik / Hesse, Janina / Contreras, Susana Andrea / Schreiber, Susanne

    Physical review. E

    2021  Volume 103, Issue 1-1, Page(s) 12407

    Abstract: Neuronal voltage dynamics of regularly firing neurons typically has one stable attractor: either a fixed point (like in the subthreshold regime) or a limit cycle that defines the tonic firing of action potentials (in the suprathreshold regime). In two of ...

    Abstract Neuronal voltage dynamics of regularly firing neurons typically has one stable attractor: either a fixed point (like in the subthreshold regime) or a limit cycle that defines the tonic firing of action potentials (in the suprathreshold regime). In two of the three spike onset bifurcation sequences that are known to give rise to all-or-none type action potentials, however, the resting-state fixed point and limit cycle spiking can coexist in an intermediate regime, resulting in bistable dynamics. Here, noise can induce switches between the attractors, i.e., between rest and spiking, and thus increase the variability of the spike train compared to neurons with only one stable attractor. Qualitative features of the resulting spike statistics depend on the spike onset bifurcations. This paper focuses on the creation of the spiking limit cycle via the saddle-homoclinic orbit (HOM) bifurcation and derives interspike interval (ISI) densities for a conductance-based neuron model in the bistable regime. The ISI densities of bistable homoclinic neurons are found to be unimodal yet distinct from the inverse Gaussian distribution associated with the saddle-node-on-invariant-cycle bifurcation. It is demonstrated that for the HOM bifurcation the transition between rest and spiking is mainly determined along the downstroke of the action potential-a dynamical feature that is not captured by the commonly used reset neuron models. The deduced spike statistics can help to identify HOM dynamics in experimental data.
    MeSH term(s) Action Potentials ; Models, Neurological ; Neurons/cytology ; Nonlinear Dynamics
    Language English
    Publishing date 2021-02-04
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2844562-4
    ISSN 2470-0053 ; 2470-0045
    ISSN (online) 2470-0053
    ISSN 2470-0045
    DOI 10.1103/PhysRevE.103.012407
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Descriptive epidemiology of snakebites in the Veraguas province of Panama, 2007-2008.

    Pecchio, Maydelin / Suárez, José A / Hesse, Susana / Hersh, Andrew M / Gundacker, Nathan D

    Transactions of the Royal Society of Tropical Medicine and Hygiene

    2018  Volume 112, Issue 10, Page(s) 463–466

    Abstract: Background: Panama has the highest incidence of snakebites in Central America, however, few studies have looked at the epidemiology of human snakebites in Panama.: Methods: This retrospective, single-center study reviewed individuals who sustained a ... ...

    Abstract Background: Panama has the highest incidence of snakebites in Central America, however, few studies have looked at the epidemiology of human snakebites in Panama.
    Methods: This retrospective, single-center study reviewed individuals who sustained a snakebite from 2007-2008. Demographic data, disease severity, species of snake, treatment, infectious complications and antibiotic usage were collected from the hospital records.
    Results: Data were collected over a 2-y period, with a total of 390 records of snakebites. Bothrops asper was responsible for 43.8% of cases and the majority of the cases occurred during the rainy season. The majority of bites (74.7%) occurred on the hands, feet or toes. Antivenom was used in 55% of patients and 67% of patients received tetanus toxoid. Only 8.7% of individuals presented to the hospital within 1 h of envenomation and more than 25% presented >6 h after envenomation.
    Conclusions: B. asper is responsible for the majority of snakebites in the Veraguas province of Panama. Snakebites tend to occur during the rainy season, with the majority of bites occurring on the feet. Several management factors need to improve in Panama: time to presentation, which is prolonged in the majority of cases, and antivenom, antibiotic and tetanus toxoid delivery should be standardized to optimize care.
    MeSH term(s) Adolescent ; Adult ; Animals ; Anti-Bacterial Agents/therapeutic use ; Antivenins/therapeutic use ; Child ; Child, Preschool ; Emergency Service, Hospital/statistics & numerical data ; Female ; Humans ; Incidence ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Panama/epidemiology ; Retrospective Studies ; Snake Bites/complications ; Snake Bites/drug therapy ; Snake Bites/epidemiology ; Snakes/classification ; Species Specificity ; Urban Renewal/statistics & numerical data ; Young Adult
    Chemical Substances Anti-Bacterial Agents ; Antivenins
    Language English
    Publishing date 2018-08-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 441375-1
    ISSN 1878-3503 ; 0035-9203
    ISSN (online) 1878-3503
    ISSN 0035-9203
    DOI 10.1093/trstmh/try076
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Book ; Online: Firing statistics in the bistable regime of neurons with homoclinic spike generation

    Schleimer, Jan-Hendrik / Hesse, Janina / Contreras, Susana Andrea / Schreiber, Susanne

    2019  

    Abstract: Neuronal voltage dynamics of regularly firing neurons typically has one stable attractor: either a fixed point (like in the subthreshold regime) or a limit cycle that defines the tonic firing of action potentials (in the suprathreshold regime). In two of ...

    Abstract Neuronal voltage dynamics of regularly firing neurons typically has one stable attractor: either a fixed point (like in the subthreshold regime) or a limit cycle that defines the tonic firing of action potentials (in the suprathreshold regime). In two of the three spike onset bifurcation sequences that are known to give rise to all-or-none type action potentials, however, the resting-state fixpoint and limit cycle spiking can coexist in an intermediate regime, resulting in bistable dynamics. Here, noise can induce switches between the attractors, i.e., between rest and spiking, and thus increase the variability of the spike train compared to neurons with only one stable attractor. Qualitative features of the resulting spike statistics depend on the spike onset bifurcations. This study focuses on the creation of the spiking limit cycle via the saddle-homoclinic orbit (HOM) bifurcation and derives interspike interval (ISI) densities for a conductance-based neuron model in the bistable regime. The ISI densities of bistable homoclinic neurons are found to be unimodal yet distinct from the inverse Gaussian distribution associated with the saddle-node-on-invariant-cycle (SNIC) bifurcation. It is demonstrated that for the HOM bifurcation the transition between rest and spiking is mainly determined along the downstroke of the action potential -- a dynamical feature that is not captured by the commonly used reset neuron models. The deduced spike statistics can help to identify HOM dynamics in experimental data.
    Keywords Quantitative Biology - Neurons and Cognition
    Subject code 612
    Publishing date 2019-02-03
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article: 18

    Bulat, Flaviu / Hesse, Friederike / Hu, De-En / Ros, Susana / Willminton-Holmes, Connor / Xie, Bangwen / Attili, Bala / Soloviev, Dmitry / Aigbirhio, Franklin / Leeper, Finian J / Brindle, Kevin M / Neves, André A

    EJNMMI research

    2020  Volume 10, Issue 1, Page(s) 151

    Abstract: Introduction: Trialing novel cancer therapies in the clinic would benefit from imaging agents that can detect early evidence of treatment response. The timing, extent and distribution of cell death in tumors following treatment can give an indication of ...

    Abstract Introduction: Trialing novel cancer therapies in the clinic would benefit from imaging agents that can detect early evidence of treatment response. The timing, extent and distribution of cell death in tumors following treatment can give an indication of outcome. We describe here an
    Methods: A one-pot, two-step automated synthesis of N-(5-[
    Results: 18
    Conclusion: The rapid clearance of
    Language English
    Publishing date 2020-12-09
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2619892-7
    ISSN 2191-219X
    ISSN 2191-219X
    DOI 10.1186/s13550-020-00738-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Hantavirus in Panama: Twenty Years of Epidemiological Surveillance Experience.

    Armién, Blas / Muñoz, Carlos / Cedeño, Hector / Salazar, Jacqueline R / Salinas, Tybbyssay P / González, Publio / Trujillo, José / Sánchez, Deyanira / Mariñas, Jamileth / Hernández, Ayvar / Cruz, Harmodio / Villarreal, Leisy Yovany / Grimaldo, Elba / González, Samuel / Nuñez, Heydy / Hesse, Susana / Rivera, Fernando / Edwards, George / Chong, Ricardo /
    Mendoza, Ovidio / Meza, Martín / Herrera, Milagro / Kant, Rudick / Esquivel, Raul / Estripeaut, Dora / Serracín, Demetrio / Denis, Bernardino / Robles, Esthefani / Mendoza, Yaxelis / Gonzalez, Gloria / Tulloch, Felicia / Pascale, Juan Miguel / Dunnum, Jonathan L / Cook, Joseph A / Armién, Anibal G / Gracia, Fernando / Guerrero, Gladys Alicia / de Mosca, Itza

    Viruses

    2023  Volume 15, Issue 6

    Abstract: Twenty years have passed since the emergence of hantavirus zoonosis in Panama at the beginning of this millennium. We provide an overview of epidemiological surveillance of hantavirus disease (hantavirus pulmonary syndrome and hantavirus fever) during ... ...

    Abstract Twenty years have passed since the emergence of hantavirus zoonosis in Panama at the beginning of this millennium. We provide an overview of epidemiological surveillance of hantavirus disease (hantavirus pulmonary syndrome and hantavirus fever) during the period 1999-2019 by including all reported and confirmed cases according to the case definition established by the health authority. Our findings reveal that hantavirus disease is a low-frequency disease, affecting primarily young people, with a relatively low case-fatality rate compared to other hantaviruses in the Americas (e.g., ANDV and SNV). It presents an annual variation with peaks every 4-5 years and an interannual variation influenced by agricultural activities. Hantavirus disease is endemic in about 27% of Panama, which corresponds to agroecological conditions that favor the population dynamics of the rodent host,
    MeSH term(s) Animals ; Communicable Diseases ; Hantavirus Infections/epidemiology ; Hantavirus Pulmonary Syndrome/epidemiology ; Hemorrhagic Fever with Renal Syndrome ; Orthohantavirus ; Panama/epidemiology ; Rodentia ; Sigmodontinae
    Language English
    Publishing date 2023-06-19
    Publishing country Switzerland
    Document type Journal Article ; Review ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2516098-9
    ISSN 1999-4915 ; 1999-4915
    ISSN (online) 1999-4915
    ISSN 1999-4915
    DOI 10.3390/v15061395
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Case Report: First Confirmed Case of Coinfection of SARS-CoV-2 With

    Hesse, Susana / Nuñez, Heydy / Salazar, Jacqueline R / Salinas, Tybbysay P / Barrera, Erika / Chong, Ricardo / Torres, Saúl / Cumbrera, Amarellys / Olivares, Idiamín / Junco, Aimee / Matteo, Christian / González, Claudia / Chavarría, Oris / Moreno, Ambar / Góndola, Jessica / Ábrego, Leyda / Díaz, Yamilka / Pitti, Yaneth / Franco, Danilo /
    Martínez-Montero, Mabel / Pascale, Juan Miguel / López-Vergès, Sandra / Martínez, Alexander A / Armién, Blas

    Frontiers in tropical diseases

    2021  Volume 2, Page(s) 769330

    Abstract: The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a major international public health concern. The World Health Organization (WHO) declared the pandemic of coronavirus disease 2019 (COVID-19) on March 11, 2020. In ... ...

    Abstract The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a major international public health concern. The World Health Organization (WHO) declared the pandemic of coronavirus disease 2019 (COVID-19) on March 11, 2020. In Panama, the first SARS-CoV-2 infection was confirmed on March 9, 2020, and the first fatal case associated to COVID-19 was reported on March 10. This report presents the case of a 44-year-old female who arrived at the hospital with a respiratory failure, five days after the first fatal COVID-19 case, and who was living in a region where hantavirus pulmonary syndrome cases caused by
    Language English
    Publishing date 2021-11-10
    Publishing country Switzerland
    Document type Case Reports
    ISSN 2673-7515
    ISSN (online) 2673-7515
    DOI 10.3389/fitd.2021.769330
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: 18F-C2Am

    Flaviu Bulat / Friederike Hesse / De-En Hu / Susana Ros / Connor Willminton-Holmes / Bangwen Xie / Bala Attili / Dmitry Soloviev / Franklin Aigbirhio / Finian. J. Leeper / Kevin M. Brindle / André A. Neves

    EJNMMI Research, Vol 10, Iss 1, Pp 1-

    a targeted imaging agent for detecting tumor cell death in vivo using positron emission tomography

    2020  Volume 14

    Abstract: Abstract Introduction Trialing novel cancer therapies in the clinic would benefit from imaging agents that can detect early evidence of treatment response. The timing, extent and distribution of cell death in tumors following treatment can give an ... ...

    Abstract Abstract Introduction Trialing novel cancer therapies in the clinic would benefit from imaging agents that can detect early evidence of treatment response. The timing, extent and distribution of cell death in tumors following treatment can give an indication of outcome. We describe here an 18F-labeled derivative of a phosphatidylserine-binding protein, the C2A domain of Synaptotagmin-I (C2Am), for imaging tumor cell death in vivo using PET. Methods A one-pot, two-step automated synthesis of N-(5-[18F]fluoropentyl)maleimide (60 min synthesis time, > 98% radiochemical purity) has been developed, which was used to label the single cysteine residue in C2Am within 30 min at room temperature. Binding of 18F-C2Am to apoptotic and necrotic tumor cells was assessed in vitro, and also in vivo, by dynamic PET and biodistribution measurements in mice bearing human tumor xenografts treated with a TRAILR2 agonist or with conventional chemotherapy. C2Am detection of tumor cell death was validated by correlation of probe binding with histological markers of cell death in tumor sections obtained immediately after imaging. Results 18F-C2Am showed a favorable biodistribution profile, with predominantly renal clearance and minimal retention in spleen, liver, small intestine, bone and kidney, at 2 h following probe administration. 18F-C2Am generated tumor-to-muscle (T/m) ratios of 6.1 ± 2.1 and 10.7 ± 2.4 within 2 h of probe administration in colorectal and breast tumor models, respectively, following treatment with the TRAILR2 agonist. The levels of cell death (CC3 positivity) following treatment were 12.9–58.8% and 11.3–79.7% in the breast and colorectal xenografts, respectively. Overall, a 20% increase in CC3 positivity generated a one unit increase in the post/pre-treatment tumor contrast. Significant correlations were found between tracer uptake post-treatment, at 2 h post-probe administration, and histological markers of cell death (CC3: Pearson R = 0.733, P = 0.0005; TUNEL: Pearson R = 0.532, P = 0.023). Conclusion The ...
    Keywords Cell death ; PET ; C2Am ; Synaptotagmin-I ; Tumor ; TRAILR2 ; Medical physics. Medical radiology. Nuclear medicine ; R895-920
    Language English
    Publishing date 2020-12-01T00:00:00Z
    Publisher SpringerOpen
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Cancer communication science funding trends, 2000-2012.

    Ramírez, A Susana / Galica, Kasia / Blake, Kelly D / Chou, Wen-Ying Sylvia / Hesse, Bradford W

    Journal of the National Cancer Institute. Monographs

    2013  Volume 2013, Issue 47, Page(s) 133–139

    Abstract: Background: Since 2000, the field of health communication has grown tremendously, owing largely to research funding by the National Cancer Institute (NCI). This study provides an overview of cancer communication science funding trends in the past decade. ...

    Abstract Background: Since 2000, the field of health communication has grown tremendously, owing largely to research funding by the National Cancer Institute (NCI). This study provides an overview of cancer communication science funding trends in the past decade.
    Methods: We conducted an analysis of communication-related grant applications submitted to the NCI in fiscal years 2000-2012. Using 103 keywords related to health communication, data were extracted from the Portfolio Management Application, a grants management application used at NCI. Automated coding described key grant characteristics such as mechanism and review study section. Manual coding determined funding across the cancer control continuum, by cancer site, and by cancer risk factors.
    Results: A total of 3307 unique grant applications met initial inclusion criteria; 1013 of these were funded over the 12-year period. The top funded grant mechanisms were the R01, R21, and R03. Applications were largely investigator-initiated proposals as opposed to responses to particular funding opportunity announcements. Among funded communication research, the top risk factor being studied was tobacco, and across the cancer control continuum, cancer prevention was the most common stage investigated.
    Conclusions: NCI support of cancer communication research has been an important source of growth for health communication science over the last 12 years. The analysis' findings describe NCI's priorities in cancer communication science and suggest areas for future investments.
    MeSH term(s) Early Detection of Cancer/economics ; Early Detection of Cancer/methods ; Financing, Organized/trends ; Health Communication/economics ; Health Communication/methods ; Health Communication/trends ; Humans ; National Cancer Institute (U.S.) ; Neoplasms/diagnosis ; Neoplasms/economics ; Neoplasms/prevention & control ; Neoplasms/therapy ; Research Design ; United States
    Language English
    Publishing date 2013-12
    Publishing country United States
    Document type Journal Article ; Review
    ISSN 1745-6614
    ISSN (online) 1745-6614
    DOI 10.1093/jncimonographs/lgt030
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Correlates and geographic patterns of knowledge that physical activity decreases cancer risk.

    Ramírez, A Susana / Finney Rutten, Lila J / Vanderpool, Robin C / Moser, Richard P / Hesse, Bradford W

    The journal of primary prevention

    2013  Volume 34, Issue 1-2, Page(s) 31–39

    Abstract: While many lifestyle-related cancer risk factors including tobacco use, poor diet, and sun exposure are well recognized by the general public, the role of physical activity in decreasing cancer risk is less recognized. Studies have demonstrated gender-, ... ...

    Abstract While many lifestyle-related cancer risk factors including tobacco use, poor diet, and sun exposure are well recognized by the general public, the role of physical activity in decreasing cancer risk is less recognized. Studies have demonstrated gender-, race/ethnicity-, and age-based disparities in cancer risk factor knowledge; however, beliefs and geographic factors that may be related to knowledge are under-examined. In this study, we analyzed data from the 2008 Health Information National Trends Survey to determine correlates of knowledge of the relationship between physical activity and reduced cancer risk in the adult US population. We generated geographic information system maps to examine the geographic distribution of this knowledge. Results revealed that there is confusion among US adults about the relationship between physical activity and cancer risk: Respondents who believed that cancer is not preventable had significantly lower odds of knowing that physical activity reduces cancer risk (p < .001) whereas respondents who believed that cancer is caused by one's behavior had almost two times the odds of knowing that physical activity reduces cancer risk (p < .001). Those who were aware of current physical activity guidelines were also significantly more likely to know that physical activity reduces cancer risk (p < .01). Observed geographic variability in knowledge was consistent with geographic trends in obesity and physical inactivity. Correlates of cancer risk factor knowledge point to opportunities for targeted interventions.
    MeSH term(s) Adolescent ; Adult ; Aged ; Female ; Geographic Information Systems ; Health Knowledge, Attitudes, Practice ; Humans ; Male ; Middle Aged ; Motor Activity ; Neoplasms/prevention & control ; Primary Prevention ; Risk Factors ; United States
    Language English
    Publishing date 2013-01-24
    Publishing country Netherlands
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 622512-3
    ISSN 1573-6547 ; 0278-095X
    ISSN (online) 1573-6547
    ISSN 0278-095X
    DOI 10.1007/s10935-012-0289-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Perceptions of cancer controllability and cancer risk knowledge: the moderating role of race, ethnicity, and acculturation.

    Ramírez, A Susana / Rutten, Lila J Finney / Oh, April / Vengoechea, Bryan Leyva / Moser, Richard P / Vanderpool, Robin C / Hesse, Bradford W

    Journal of cancer education : the official journal of the American Association for Cancer Education

    2013  Volume 28, Issue 2, Page(s) 254–261

    Abstract: Literature suggests racial/ethnic minorities, particularly those who are less-acculturated, have stronger fatalistic attitudes toward cancer than do non-Latino Whites. Knowledge of cancer prevention is also lower among racial/ethnic minorities. Moreover, ...

    Abstract Literature suggests racial/ethnic minorities, particularly those who are less-acculturated, have stronger fatalistic attitudes toward cancer than do non-Latino Whites. Knowledge of cancer prevention is also lower among racial/ethnic minorities. Moreover, low knowledge about cancer risk factors is often associated with fatalistic beliefs. Our study examined fatalism and cancer knowledge by race/ethnicity and explored whether race/ethnicity moderate the association of fatalism with knowledge of cancer prevention and risk factors. We analyzed data from the Health Information National Trends Survey (2008), a national probability survey, to calculate population estimates of the associations among race/ethnicity, fatalistic beliefs, and knowledge about cancer from multivariable logistic regression. Racial/ethnic minorities had higher odds of holding fatalistic beliefs and lower odds of having knowledge of cancer risk factors than non-Hispanic Whites, and important differences by acculturation among Latinos were observed. Limited evidence of the moderating effect of race/ethnicity on the relationship between fatalistic beliefs and cancer risk factor knowledge was observed. Knowledge of cancer risk factors is low among all race/ethnicities, while fatalistic beliefs about cancer are higher among racial/ethnic minorities compared with non-Hispanic Whites. Implications for cancer education efforts are discussed.
    MeSH term(s) Acculturation ; Adolescent ; Adult ; African Americans/psychology ; Aged ; Attitude to Health ; Culture ; European Continental Ancestry Group/psychology ; Exercise/psychology ; Female ; Food Preferences/ethnology ; Health Behavior/ethnology ; Health Education/ethics ; Hispanic Americans/psychology ; Humans ; Internal-External Control ; Life Style ; Male ; Middle Aged ; Neoplasms/ethnology ; Neoplasms/etiology ; Neoplasms/prevention & control ; Neoplasms/psychology ; Self Efficacy ; United States ; Young Adult
    Language English
    Publishing date 2013-01-25
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 632898-2
    ISSN 1543-0154 ; 0885-8195 ; 1543-1154
    ISSN (online) 1543-0154
    ISSN 0885-8195 ; 1543-1154
    DOI 10.1007/s13187-013-0450-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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