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Dive into the research topics where Hidemi S. Yamamoto is active.

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Featured researches published by Hidemi S. Yamamoto.


Immunity | 2015

Cervicovaginal Bacteria Are a Major Modulator of Host Inflammatory Responses in the Female Genital Tract

Melis N. Anahtar; Elizabeth H. Byrne; Kathleen E. Doherty; Brittany Bowman; Hidemi S. Yamamoto; Magali Soumillon; Nikita Padavattan; Nasreen Ismail; Amber Moodley; Mary E. Sabatini; Musie Ghebremichael; Chad Nusbaum; Curtis Huttenhower; Herbert W. Virgin; Thumbi Ndung’u; Krista Dong; Bruce D. Walker; Raina N. Fichorova; Douglas S. Kwon

Colonization by Lactobacillus in the female genital tract is thought to be critical for maintaining genital health. However, little is known about how genital microbiota influence host immune function and modulate disease susceptibility. We studied a cohort of asymptomatic young South African women and found that the majority of participants had genital communities with low Lactobacillus abundance and high ecological diversity. High-diversity communities strongly correlated with genital pro-inflammatory cytokine concentrations in both cross-sectional and longitudinal analyses. Transcriptional profiling suggested that genital antigen-presenting cells sense gram-negative bacterial products in situ via Toll-like receptor 4 signaling, contributing to genital inflammation through activation of the NF-κB signaling pathway and recruitment of lymphocytes by chemokine production. Our study proposes a mechanism by which cervicovaginal microbiota impact genital inflammation and thereby might affect a womans reproductive health, including her risk of acquiring HIV.


Mbio | 2011

Maternal Microbe-Specific Modulation of Inflammatory Response in Extremely Low-Gestational-Age Newborns

Raina N. Fichorova; Andrew B. Onderdonk; Hidemi S. Yamamoto; Mary L. Delaney; Andrea M. DuBois; Elizabeth N. Allred; Alan Leviton

ABSTRACT The fetal response to intrauterine inflammatory stimuli appears to contribute to the onset of preterm labor as well as fetal injury, especially affecting newborns of extremely low gestational age. To investigate the role of placental colonization by specific groups of microorganisms in the development of inflammatory responses present at birth, we analyzed 25 protein biomarkers in dry blood spots obtained from 527 newborns delivered by Caesarean section in the 23rd to 27th gestation weeks. Bacteria were detected in placentas and characterized by culture techniques. Odds ratios for having protein concentrations in the top quartile for gestation age for individual and groups of microorganisms were calculated. Mixed bacterial vaginosis (BV) organisms were associated with a proinflammatory pattern similar to those of infectious facultative anaerobes. Prevotella and Gardnerella species, anaerobic streptococci, peptostreptococci, and genital mycoplasmas each appeared to be associated with a different pattern of elevated blood levels of inflammation-related proteins. Lactobacillus was associated with low odds of an inflammatory response. This study provides evidence that microorganisms colonizing the placenta provoke distinctive newborn inflammatory responses and that Lactobacillus may suppress these responses. IMPORTANCE Despite improved intensive care, preterm and especially extremely low-gestation-age neonates continue to be at a considerably increased risk of morbidity, mortality, and developmental problems. The fetal inflammatory response appears to contribute to the onset of preterm labor, fetal injury, and complications, underlying lifetime health challenges facing these children. This study provides evidence that bacterial colonization of the very preterm placenta is associated with distinct microorganism-specific inflammatory protein profiles in the newborn blood specimens. We also provide evidence that Lactobacillus reduces inflammatory responses in newborns. Our data support the concept that targeting of placental colonization by specific drugs or probiotics during early pregnancy holds promise for preventing not only preterm birth but also subsequent and long-lasting, inflammation-provoked late sequelae. Despite improved intensive care, preterm and especially extremely low-gestation-age neonates continue to be at a considerably increased risk of morbidity, mortality, and developmental problems. The fetal inflammatory response appears to contribute to the onset of preterm labor, fetal injury, and complications, underlying lifetime health challenges facing these children. This study provides evidence that bacterial colonization of the very preterm placenta is associated with distinct microorganism-specific inflammatory protein profiles in the newborn blood specimens. We also provide evidence that Lactobacillus reduces inflammatory responses in newborns. Our data support the concept that targeting of placental colonization by specific drugs or probiotics during early pregnancy holds promise for preventing not only preterm birth but also subsequent and long-lasting, inflammation-provoked late sequelae.


PLOS ONE | 2012

Endobiont viruses sensed by the human host - beyond conventional antiparasitic therapy.

Raina N. Fichorova; Yujin Lee; Hidemi S. Yamamoto; Yuko Takagi; Gary R. Hayes; Russell P. Goodman; Xenia Chepa-Lotrea; Olivia R. Buck; Ryan Murray; Tomasz Kula; David H. Beach; Bibhuti N. Singh; Max L. Nibert

Wide-spread protozoan parasites carry endosymbiotic dsRNA viruses with uncharted implications to the human host. Among them, Trichomonas vaginalis, a parasite adapted to the human genitourinary tract, infects globally ∼250 million each year rendering them more susceptible to devastating pregnancy complications (especially preterm birth), HIV infection and HPV-related cancer. While first-line antibiotic treatment (metronidazole) commonly kills the protozoan pathogen, it fails to improve reproductive outcome. We show that endosymbiotic Trichomonasvirus, highly prevalent in T. vaginalis clinical isolates, is sensed by the human epithelial cells via Toll-like receptor 3, triggering Interferon Regulating Factor -3, interferon type I and proinflammatory cascades previously implicated in preterm birth and HIV-1 susceptibility. Metronidazole treatment amplified these proinflammatory responses. Thus, a new paradigm targeting the protozoan viruses along with the protozoan host may prevent trichomoniasis-attributable inflammatory sequelae.


Mbio | 2011

Novel Vaginal Microflora Colonization Model Providing New Insight into Microbicide Mechanism of Action

Raina N. Fichorova; Hidemi S. Yamamoto; Mary L. Delaney; Andrew B. Onderdonk; Gustavo F. Doncel

ABSTRACT Several broad-spectrum microbicides, including cellulose sulfate (CS), have passed conventional preclinical and phase I clinical safety evaluation and yet have failed to protect women from acquiring HIV-1 in phase II/III trials. Concerns have been raised that current preclinical algorithms are deficient in addressing the complexity of the microflora-regulated vaginal mucosal barrier. We applied a novel microflora-colonized model to evaluate CS and hydroxyethylcellulose (HEC), which is used as a “universal placebo” in microbicide trials. Cervicovaginal epithelial cultures were colonized with normal vaginal microflora isolates representing common Lactobacillus species used as probiotics (L. acidophilus and L. crispatus) or Prevotella bivia and Atopobium vaginae, most prevalent in the disturbed microflora of bacterial vaginosis (BV). At baseline, all strains maintained constant epithelium-associated CFUs without inducing cytotoxicity and apoptosis. CS selectively reduced epithelium-associated CFUs and (to a lesser extent) planktonic CFUs, most significantly affecting L. crispatus. Inducing only minor changes in sterile epithelial cultures, CS induced expression of innate immunity mediators (RANTES, interleukin-8 [IL-8], and secretory leukocyte protease inhibitor [SLPI]) in microflora-colonized epithelia, most significantly potentiating effects of bacteria causing BV. In the absence of CS, all bacterial strains except L. acidophilus activated NF-κB, although IL-8 and RANTES levels were increased by the presence of BV-causing bacteria only. CS enhanced NF-κB activation in a dose-dependent manner under all conditions, including L. acidophilus colonization. HEC remained inert. These results offer insights into possible mechanisms of CS clinical failure. The bacterially colonized cervicovaginal model reveals unique aspects of microflora-epithelium-drug interactions and innate immunity in the female genital tract and should become an integral part of preclinical safety evaluation of anti-HIV microbicides and other vaginal formulations. IMPORTANCE This report provides experimental evidence supporting the concept that the vaginal microflora regulates the epithelial innate immunity in a species- and strain-specific manner and that topically applied microbicides may alter both the bacterial and epithelial components of this homeostatic interaction. Our data also highlight the importance of differentiating the effects of biomedical interventions on epithelium-associated versus conventional planktonic bacterial growth when assessing vaginal mucosal health and immunity. This report provides experimental evidence supporting the concept that the vaginal microflora regulates the epithelial innate immunity in a species- and strain-specific manner and that topically applied microbicides may alter both the bacterial and epithelial components of this homeostatic interaction. Our data also highlight the importance of differentiating the effects of biomedical interventions on epithelium-associated versus conventional planktonic bacterial growth when assessing vaginal mucosal health and immunity.


Sexually Transmitted Infections | 2013

The Villain Team-Up or how Trichomonas vaginalis and bacterial vaginosis alter innate immunity in concert

Raina N. Fichorova; Olivia R. Buck; Hidemi S. Yamamoto; Titilayo Fashemi; Hassan Y. Dawood; Bisiayo Fashemi; Gary R. Hayes; David H. Beach; Yuko Takagi; Mary L. Delaney; Max L. Nibert; Bibhuti N. Singh; Andrew B. Onderdonk

Objectives Complex interactions of vaginal microorganisms with the genital tract epithelium shape mucosal innate immunity, which holds the key to sexual and reproductive health. Bacterial vaginosis (BV), a microbiome-disturbance syndrome prevalent in reproductive-age women, occurs commonly in concert with trichomoniasis, and both are associated with increased risk of adverse reproductive outcomes and viral infections, largely attributable to inflammation. To investigate the causative relationships among inflammation, BV and trichomoniasis, we established a model of human cervicovaginal epithelial cells colonised by vaginal Lactobacillus isolates, dominant in healthy women, and common BV species (Atopobium vaginae, Gardnerella vaginalis and Prevotella bivia). Methods Colonised epithelia were infected with Trichomonas vaginalis (TV) or exposed to purified TV virulence factors (membrane lipophosphoglycan (LPG), its ceramide-phosphoinositol-glycan core (CPI-GC) or the endosymbiont Trichomonas vaginalis virus (TVV)), followed by assessment of bacterial colony-forming units, the mucosal anti-inflammatory microbicide secretory leucocyte protease inhibitor (SLPI), and chemokines that drive pro-inflammatory, antigen-presenting and T cells. Results TV reduced colonisation by Lactobacillus but not by BV species, which were found inside epithelial cells. TV increased interleukin (IL)-8 and suppressed SLPI, likely via LPG/CPI-GC, and upregulated IL-8 and RANTES, likely via TVV as suggested by use of purified pathogenic determinants. BV species A vaginae and G vaginalis induced IL-8 and RANTES, and also amplified the pro-inflammatory responses to both LPG/CPI-GC and TVV, whereas P bivia suppressed the TV/TVV-induced chemokines. Conclusions These molecular host–parasite–endosymbiont–bacteria interactions explain epidemiological associations and suggest a revised paradigm for restoring vaginal immunity and preventing BV/TV-attributable inflammatory sequelae in women.


Hypertension | 2013

Urinary Excretion of C5b-9 in Severe Preeclampsia: Tipping the Balance of Complement Activation in Pregnancy

Richard M. Burwick; Raina N. Fichorova; Hassan Y. Dawood; Hidemi S. Yamamoto; Bruce B. Feinberg

The complement cascade is activated in normal pregnancy, and excessive complement activation propagates the systemic inflammatory response in severe preeclampsia. Consequently, biomarkers of complement dysregulation may be useful for prediction or treatment of disease. Because renal damage with proteinuria is a characteristic pathological feature of preeclampsia, we hypothesized that complement markers in urine, rather than plasma, could better reflect complement dysregulation in disease. To investigate this, we performed a case–control study of pregnant women, enrolling 25 cases with severe preeclampsia, 25 controls with chronic hypertension, and 25 healthy controls without hypertension matched by gestational age and parity. Subjects were recruited from the Brigham and Women’s Hospital from March 2012 to March 2013. Urine and blood samples were collected on the day of enrollment, with complement activation (C3a, C5a, and C5b-9) measured by ELISA. Severe preeclampsia was associated with marked elevations in urinary C5b-9 (median [interquartile range], 4.3 [1.2–15.1] ng/mL) relative to subjects with chronic hypertension (0 [0–0]) and healthy controls (0 [0–0]; P <0.0001). Urinary excretion of C5b-9 was detected in 96% of cases with severe preeclampsia, 12% of controls with chronic hypertension, and 8% of healthy controls. Cases were also notable for significantly greater urinary excretion of C3a and C5a. Plasma levels of C5a and C5b-9, but not C3a, were increased in the cases with severe preeclampsia compared with healthy controls; however, they did not distinguish preeclampsia from chronic hypertension, supporting our hypothesis that complement markers in urine, rather than plasma, better reflect complement dysregulation. Complement inhibition is an intriguing treatment option for patients with severe preeclampsia. # Novelty and Significance {#article-title-54}The complement cascade is activated in normal pregnancy, and excessive complement activation propagates the systemic inflammatory response in severe preeclampsia. Consequently, biomarkers of complement dysregulation may be useful for prediction or treatment of disease. Because renal damage with proteinuria is a characteristic pathological feature of preeclampsia, we hypothesized that complement markers in urine, rather than plasma, could better reflect complement dysregulation in disease. To investigate this, we performed a case–control study of pregnant women, enrolling 25 cases with severe preeclampsia, 25 controls with chronic hypertension, and 25 healthy controls without hypertension matched by gestational age and parity. Subjects were recruited from the Brigham and Women’s Hospital from March 2012 to March 2013. Urine and blood samples were collected on the day of enrollment, with complement activation (C3a, C5a, and C5b-9) measured by ELISA. Severe preeclampsia was associated with marked elevations in urinary C5b-9 (median [interquartile range], 4.3 [1.2–15.1] ng/mL) relative to subjects with chronic hypertension (0 [0–0]) and healthy controls (0 [0–0]; P<0.0001). Urinary excretion of C5b-9 was detected in 96% of cases with severe preeclampsia, 12% of controls with chronic hypertension, and 8% of healthy controls. Cases were also notable for significantly greater urinary excretion of C3a and C5a. Plasma levels of C5a and C5b-9, but not C3a, were increased in the cases with severe preeclampsia compared with healthy controls; however, they did not distinguish preeclampsia from chronic hypertension, supporting our hypothesis that complement markers in urine, rather than plasma, better reflect complement dysregulation. Complement inhibition is an intriguing treatment option for patients with severe preeclampsia.


Journal of Reproductive Immunology | 2011

Persistence after birth of systemic inflammation associated with umbilical cord inflammation

Alan Leviton; Jonathan L. Hecht; Elizabeth N. Allred; Hidemi S. Yamamoto; Raina N. Fichorova; Olaf Dammann

Intrauterine inflammation is followed by elevated concentrations of inflammation-related proteins in the newborns blood. Many of these proteins have short half-lives. The persistence of this postnatal inflammation has not previously been investigated. In a sample of 834 infants born before the 28th week of gestation, 12% (103) had grade 1 or 2, and 17% (142) had grade 3, 4, or 5 umbilical cord inflammation. Concentrations of nine proteins previously shown to be associated with umbilical cord inflammation at birth were measured on the first postnatal day and at two weekly intervals after birth. We evaluated the hypothesis that children who had umbilical cord inflammation were no more likely than others to have elevated concentrations of inflammation-related proteins in postnatal blood. The concentrations of seven of the nine proteins [C-reactive protein (CRP), myeloperoxidase (MPO), IL1β, IL8, TNFα, intercellular adhesion molecule-1 (ICAM3), and matrix metalloproteinase (MMP9)] showed a tendency to be elevated on day 7 among infants with funisitis. Adjusting for gestational age, growth restriction, and three postnatal exposures (ventilation on day 7, presumed and definite early bacteremia, and Bell stage III necrotizing endocolitis) did not diminish the elevated odds ratios of concentrations in the top quartile (for gestational age and day the specimen was obtained) of MPO, IL1β, TNFα, IL8, ICAM3, and MMP9. The persistence of a relationship between umbilical cord inflammation and elevated blood concentrations of inflammation-related proteins on postnatal day 7 suggests the existence of phenomena that contribute to a reinforcement loop and thereby sustained systemic inflammation.


Proceedings of the National Academy of Sciences of the United States of America | 2015

Multitarget, quantitative nanoplasmonic electrical field-enhanced resonating device (NE2RD) for diagnostics

Fatih Inci; Chiara Filippini; Murat Baday; Mehmet O. Ozen; Semih Calamak; Naside Gozde Durmus; ShuQi Wang; Emily Hanhauser; Kristen S. Hobbs; Franceline Juillard; Ping Ping Kuang; Michael L. Vetter; Margot Carocci; Hidemi S. Yamamoto; Yuko Takagi; Umit Hakan Yildiz; Demir Akin; Duane R. Wesemann; Amit Singhal; Priscilla L. Yang; Max L. Nibert; Raina N. Fichorova; Daryl Lau; Timothy J. Henrich; Kenneth M. Kaye; Steven C. Schachter; Daniel R. Kuritzkes; Lars M. Steinmetz; Sanjiv S. Gambhir; Ronald W. Davis

Significance Biosensing technologies have significant impact on medical diagnostics but difficulties in the handling of complex biospecimens, portability, and nonlinearity in dynamic detection range present considerable technical bottlenecks in their translation into clinical settings. Here, we present the nanoplasmonic electrical field-enhanced resonating device (NE2RD) that detects and quantifies multiple biotargets from distinct clinical specimens (i.e., saliva, serum, and whole blood) with a broad linear dynamic range. Unlike conventional platforms, the NE2RD does not require lengthy sample-preparation steps, skilled personnel, or expensive infrastructure. Further, as a model clinical validation study, we monitored chemotherapy effects on viral load for coinfected patients on a single platform. Therefore, the portable NE2RD can be broadly applied to primary care and point-of-care settings with multiple clinical applications. Recent advances in biosensing technologies present great potential for medical diagnostics, thus improving clinical decisions. However, creating a label-free general sensing platform capable of detecting multiple biotargets in various clinical specimens over a wide dynamic range, without lengthy sample-processing steps, remains a considerable challenge. In practice, these barriers prevent broad applications in clinics and at patients’ homes. Here, we demonstrate the nanoplasmonic electrical field-enhanced resonating device (NE2RD), which addresses all these impediments on a single platform. The NE2RD employs an immunodetection assay to capture biotargets, and precisely measures spectral color changes by their wavelength and extinction intensity shifts in nanoparticles without prior sample labeling or preprocessing. We present through multiple examples, a label-free, quantitative, portable, multitarget platform by rapidly detecting various protein biomarkers, drugs, protein allergens, bacteria, eukaryotic cells, and distinct viruses. The linear dynamic range of NE2RD is five orders of magnitude broader than ELISA, with a sensitivity down to 400 fg/mL This range and sensitivity are achieved by self-assembling gold nanoparticles to generate hot spots on a 3D-oriented substrate for ultrasensitive measurements. We demonstrate that this precise platform handles multiple clinical samples such as whole blood, serum, and saliva without sample preprocessing under diverse conditions of temperature, pH, and ionic strength. The NE2RD’s broad dynamic range, detection limit, and portability integrated with a disposable fluidic chip have broad applications, potentially enabling the transition toward precision medicine at the point-of-care or primary care settings and at patients’ homes.


Cytokine | 2012

Relationships among the concentrations of 25 inflammation-associated proteins during the first postnatal weeks in the blood of infants born before the 28th week of gestation.

Alan Leviton; Elizabeth N. Allred; Hidemi S. Yamamoto; Raina N. Fichorova

BACKGROUND Inflammation appears to be involved in processes leading to organ damage in preterm newborns, yet little is known about the relationships among elevated concentrations of inflammation-associated proteins in the blood of preterm newborns. METHODS In this exploratory study, we used an electrochemiluminescence method to measure 25 proteins in blood obtained on postnatal day 1 (range 1-3), day 7 (range 5-8), and day 14 (range 12-15) from 939 children born before the 28th week of gestation and evaluated to what extent those whose concentration of each protein was elevated (defined as in the highest quartile for gestational age and day the specimen was obtained) also had an elevated concentration of every other protein the same day or on a day 1 or 2 weeks later (p<.0001). RESULTS On each of the 3 days assessed, elevated concentrations of 17 proteins were associated with elevated concentrations of 15 or more of the other 24 proteins. VEGF, VEGF-R1, VEGF-R2 were among these proteins, while IGFBP-1 was associated with 13 other proteins on day 7. An elevated concentration of eight proteins on day 1 predicted an elevated concentration of 10 or more proteins on day 7, while an elevated concentration of only two proteins on day 7 were associated with elevated concentrations of 10 or more proteins on day-14. Few associations were seen between days 1 and 14. CONCLUSIONS/INFERENCES: Inflammation is a diffuse process in ELGANs, with elevated concentrations of cytokines, chemokines, adhesion molecules, matrix metalloproteinases, a growth factor and its receptors, as well as a growth factor binding protein associated with each other the same day, as well as on subsequent days.


BMC Microbiology | 2013

Homeostatic properties of Lactobacillus jensenii engineered as a live vaginal anti-HIV microbicide

Hidemi S. Yamamoto; Qiang Xu; Raina N. Fichorova

BackgroundVaginal probiotics are investigated as a binary strategy for prevention of bacterial vaginosis and HIV. We applied an innovative experimental model using primary and immortalized human cervical and vaginal epithelial cells to assess the functional properties of Lactobacillus jensenii, a predominant constituent of the healthy vaginal microbiome, engineered to express the HIV-1 entry inhibitor modified cyanovirin-N (mCV-N). In this model bacteria colonize the epithelial cells over a period of 24-72 h. Staurosporine and the Toll-like receptor 2/6 ligand macrophage-activating lipopeptide-2 (MALP-2) serve as positive controls for apoptosis and proinflammatory activation, respectively. In 24-hour intervals, the colonized epithelium is assessed microscopically, supernatants are collected for measurement of soluble immunoinflammatory mediators and production of CV-N, and cells are lysed for assessment of: 1) apoptosis by cleaved versus total caspase-3 assay; 2) NF-κB activation by a luciferase reporter assay; or 3) epithelia-associated colony forming units (CFU) in Brucella agar.ResultsWild type (WT) L. jensenii 1153 consistently colonized cervical and vaginal cells in the absence of epithelial damage and apoptosis. The bioengineered derivatives expressing mCV-N or control plasmids showed the same stable colonization pattern, which was reproducible between technologists and bacterial batches (CFU coefficient of variation <10% within and between experiments and epithelial cell types). MALP-2 activated NF-κB and caused fold-increased levels of proinflammatory mediators with clinically established significance in the cervicovaginal environment (IL-1α, IL-1β, IL-6, TNF-α, IL-8, RANTES, MIP-3α, and ICAM-1), measured by a multiplex electrochemiluminescence assay. At the same time levels of protective anti-inflammatory mediators interleukin 1 receptor antagonist (IL-1RA) and secretory leukocyte protease inhibitor (SLPI), both measured by ELISA, remained constant (IL-1RA) or moderately increased (SLPI). Similarly to MALP-2, colonization by L. jensenii WT activated NF-κB; however, unlike the synthetic TLR2/6 ligand, the live microorganisms did not induce significant changes in the secreted levels across all inflammation-associated proteins. The mCV-N production and function were confirmed by western blot and a HIV-1 gp120 binding assay, respectively. The bioengineered lactobacilli expressed mCV-N with anti-HIV activity preserved in the epithelial cell context and caused no significant immunoinflammatory changes as compared to the WT L. jensenii.ConclusionsThese results highlight the translational value of the colonization model and justify further clinical investigation of the homeostatic and anti-HIV effectiveness of the L. jensenii derivates.

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Raina N. Fichorova

Brigham and Women's Hospital

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Hassan Y. Dawood

Brigham and Women's Hospital

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Titilayo Fashemi

Brigham and Women's Hospital

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Alan Leviton

Boston Children's Hospital

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Andrew B. Onderdonk

Brigham and Women's Hospital

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Bruce B. Feinberg

Brigham and Women's Hospital

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Allison F. Vitonis

Brigham and Women's Hospital

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Heiner Boeing

Free University of Berlin

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