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Recognising and responding appropriately to emotions is critical to adaptive psychological functioning. Psychopathic traits (e.g. callous, manipulative, impulsive, antisocial) are related to differences in recognition and response when emotion is conveyed through facial expressions and language. Use of emotional music stimuli represents a promising approach to improve our understanding of the specific emotion processing difficulties underlying psychopathic traits because it decouples recognition of emotion from cues directly conveyed by other people (e.g. facial signals). In Experiment 1, participants listened to clips of emotional music and identified the emotional content (Sample 1, N = 196) or reported on their feelings elicited by the music (Sample 2, N = 197). Participants accurately recognised (t(195) = 32.78, p < .001, d = 4.69) and reported feelings consistent with (t(196) = 7.84, p < .001, d = 1.12) the emotion conveyed in the music. However, psychopathic traits were associated with reduced emotion recognition accuracy (F(1, 191) = 19.39, p < .001) and reduced likelihood of feeling the emotion (F(1, 193) = 35.45, p < .001), particularly for fearful music. In Experiment 2, we replicated findings for broad difficulties with emotion recognition (Sample 3, N = 179) and emotional resonance (Sample 4, N = 199) associated with psychopathic traits. Results offer new insight into emotion recognition and response difficulties that are associated with psychopathic traits.

Bacterial abortive-infection systems limit the spread of foreign invaders by shutting down or killing infected cells before the invaders can replicate1,2. Several RNA-targeting CRISPR–Cas systems (that is, types III and VI) cause abortive-infection phenotypes by activating indiscriminate nucleases3–5. However, a CRISPR-mediated abortive mechanism that leverages indiscriminate DNase activity of an RNA-guided single-effector nuclease has yet to be observed. Here we report that RNA targeting by the type V single-effector nuclease Cas12a2 drives abortive infection through non-specific cleavage of double-stranded DNA (dsDNA). After recognizing an RNA target with an activating protospacer-flanking sequence, Cas12a2 efficiently degrades single-stranded RNA (ssRNA), single-stranded DNA (ssDNA) and dsDNA. Within cells, the activation of Cas12a2 induces an SOS DNA-damage response and impairs growth, preventing the dissemination of the invader. Finally, we harnessed the collateral activity of Cas12a2 for direct RNA detection, demonstrating that Cas12a2 can be repurposed as an RNA-guided RNA-targeting tool. These findings expand the known defensive abilities of CRISPR–Cas systems and create additional opportunities for CRISPR technologies.

Due to the limited number of corridors multi circuit line configurations are often applied. These overhead lines frequently consist of high towers that are subject to lightning strokes. In case of higher current amplitudes and higher footing resistances due to bad earthing conditions back-flashovers are caused leading to common mode failures and to severe outages. The paper describes investigations performed by means of computer simulations to identify the towers of a multi-circuit line consisting of voltage levels 380 kV, 220 kV and 110 kV that are endangered by back-flashovers of the 110-kV double-circuit lines. The footing resistance of towers of the targeted line section has been measured by an instrument at high-frequency. Influence of various factors on the back-flashover over 110 kV insulator strings has been studied by means of EMTP-ATP simulations. Different current waveforms of the lightning stroke have been used to represent the first stroke and subsequent strokes. The towers are represented by the models described in [3], [8]. Available flashover analysis methods [7], [8], [12], [13] like leader development method by Pigini et al and by Motoyama, and voltage-time integration method by Kind have been applied. The towers at which back-flashover is more likely to occur than at other towers are identified by the time integral of voltage according to Kind. Various factors like tower footing impedance, tower surge impedance and tower height are considered. Application of line a surge arrester is shown to be a successful mitigation technique to reduce the back-flashover rate of those 110 kV lines. The lightning overvoltage performance of surge arresters has been analyzed by means of digital simulations. Based on the results of investigations line arresters were installed on the towers in question. Since the installation no further common mode failure has been observed.

Obtaining well diffracting crystals of membrane proteins is often challenging, but chances can be improved by crystallizing them in lipidic conditions that mimic their natural membrane environments. One approach is the high lipid–detergent (HiLiDe) method, which works by mixing the target protein with high concentrations of lipid and detergent prior to crystallization. Although this approach is convenient and flexible, understanding the effects of systematically varying lipid/detergent ratios and a characterization of the lipid phases that form during crystallization would be useful. Here, a HiLiDe phase diagram is reported for the model membrane protein MhsT, which tracks the precipitation and crystallization zones as a function of lipid and detergent concentrations, and is augmented with data on crystal sizes and diffraction properties. Additionally, the crystallization of SERCA1a solubilized directly with native lipids is characterized as a function of detergent concentration. Finally, HiLiDe crystallization drops are analysed with transmission electron microscopy, which among other features reveals liposomes, stacked lamellae that may represent crystal precursors, and mature crystals with clearly discernible packing arrangements. The results emphasize the significance of optimizing lipid/detergent ratios over broad ranges and provide insights into the mechanism of HiLiDe crystallization.

The sodium-potassium-chloride transporter NKCC1 (SLC12A2) performs Na+-dependent Cl− and K+ ion uptake across plasma membranes. NKCC1 is important for regulating e.g. cell volume, hearing, blood pressure, and chloride gradients defining GABAergic and glycinergic signaling in brain. Here, we present a 2.6 Å resolution cryo-electron microscopy (cryo-EM) structure of human NKCC1 in the substrate-loaded (Na+, K+, 2 Cl−) and inward-facing conformation adopting an occluded state that has also been observed for the SLC6 type transporters MhsT and LeuT. Cl− binding at the Cl1 site together with the nearby K+ ion provide a crucial bridge between the LeuT-fold scaffold and bundle domains. Cl− ion binding at the Cl2 site seems to undertake a structural role similar to a conserved glutamate of SLC6 transporters and may allow for chloride-sensitive regulation of transport. Supported by functional studies in mammalian cells and computational simulations we describe the Na+ binding site and a putative Na+ release pathway along transmembrane helix 5. The results provide insight into the structure-function relationship of NKCC1 with broader implications for other SLC12 family members.

Denitrification is a form of anaerobic respiration wherein nitrate is sequentially reduced via nitrite, nitric oxide, and nitrous oxide to dinitrogen gas. The pathway has mostly been characterized in bacteria that have the complete denitrification pathway. However, each individual step can serve as a form of anaerobic respiration and many bacteria only have partial denitrification pathways. The conditions under which these partial denitrification pathways are activated have received comparatively little attention. Here we report the activity of partial denitrification pathways in two purple nonsulfur bacteria, Rhodopseudomonas palustris CGA009 and Rhodobacter capsulatus SB1003. These bacteria can use one or more denitrification steps as an electron sink during phototrophic growth or to transform energy during anaerobic respiration in the dark. In each case, nitrous oxide reduction required supplementation with a non-catalyzable denitrification intermediate. Thus, bacteria that maintain partial denitrification pathways are still subject to regulation by denitrification intermediates that they cannot use.ImportanceDenitrification is a form of microbial respiration wherein nitrate is converted into dinitrogen gas, a major component of Earth’s atmosphere, via several nitrogen oxide intermediates. Unfortunately, denitrification of nitrate in agricultural fertilizers is often incomplete, resulting in the emission of the potent greenhouse gas, nitrous oxide. Some bacteria do not have all the steps for denitrification, but many can still reduce nitrous oxide into harmless dinitrogen gas. These partial denitrifying bacteria have received little attention. Here we characterized two partial denitrifying bacteria that are capable of nitrous oxide reduction. Surprisingly, nitrous oxide reduction was induced by denitrification intermediates that the bacteria could not respire, suggesting that regulation of nitrous oxide reduction was subject to the same cues as in complete denitrifiers. This work thus informs on how partial denitrifying bacteria can contribute to, and potentially combat, greenhouse gas emissions.

Bacterial abortive-infection systems limit the spread of foreign invaders by shutting down or killing infected cells before the invaders can replicate

Ninety families from six provenances of Eucalyptus loxophleba subsp. gratiae were established near Brookton, Western Australia, and Condobolin, New South Wales, and 89 of these same families were e...

Imaging Luminance Measuring Device (ILMD) based luminous intensity distribution measurement systems are an established method for measuring the luminous intensity distribution (LID) of light sources in the far field. The advantage of this system is the high-resolution acquisition of a large angular range with one image. For the uncertainty budget, the mathematical description of the system can be divided into photometric and geometric contributions. In the following, we will present a Monte-Carlo approach to analyse the geometric contributions which are the uncertainty of measurement direction and measurement distance. Therefore, we set up a geometric system description based on kinematic transformations that describes the connection between detector and light source position. To consider all relevant input quantities we simulate the adjustment and measurement process. Finally, an analysis of the geometric input parameters is shown.

In this work, we present a method to describe the model of a goniophotometer for uncertainty analysis by state-of-the-art Universal Robotic Description Format (URDF). The parameters of the kinematic chain model are determined by measurements of the geometric properties of the goniophotometer. The uncertainties of the pose are determined using Monte Carlo (MC) simulations of the kinematic chain. The measured geometric uncertainties are input the MC simulations. The proposed framework enables high level description of kinematic chains for MC simulations of measurement systems. Furthermore, the uncertainty of the total system is demonstrated over the MC trials to prove a sufficient amount of MC trials. The results of this generic approach are evaluated against an existing model and the uncertainty determination of the same goniophotometer.

In crossover designs, each subject receives a series of treatments, one after the other in p consecutive periods. There is concern that the measurement of a subject at a given period might be influenced not only by the direct effect of the current treatment but also by a carryover effect of the treatment applied in the preceding period. Sometimes, the periods of a crossover design are arranged in a circular structure. Before the first period of the experiment itself, there is a run-in period, in which each subject receives the treatment it will receive again in the last period. No measurements are taken during the run-in period. We consider the estimate for direct effects of treatments which is not corrected for carryover effects. If there are carryover effects, this uncorrected estimate will be biased. In that situation, the quality of the estimate can be measured by the mean square error, the sum of the squared bias and the variance. We determine MSE-optimal designs, that is, designs for which the mean square error is as small as possible. Since the optimal design will in general depend on the size of the carryover effects, we also determine the efficiency of some designs compared to the locally optimal design. It turns out that circular neighbour-balanced designs are highly efficient., Journal of statistical theory and practice;Vol. 15. 2021, Art. No. 85

Neutropenic diets were adopted as a way to decrease the infection risks in immunocompromised individuals, but these diets result in significant restrictions in the variety and types of foods an individual may consume. We used a controlled before-and-after study design in consecutive pediatric and young adult patients who underwent hematopoietic stem cell transplant at our center between January 1, 2014, and December 31, 2014. From January through June, all patients were placed on a traditional neutropenic diet; on July 1, we liberalized the bone marrow transplant (BMT) diet to a modified BMT diet. We compared the incidence of bloodstream infections in the first 100 days post-transplant, incidence of norovirus in the first 100 days, total parenteral nutrition days through day 100, incidence of grade 3 to 4 graft-versus-host disease at day 100, gastrointestinal graft-versus-host disease (any stage), and 100-day overall survival. In addition, we administered an investigator-created survey to evaluate food cravings, nausea, diet limitations, and subjective quality of life. In total, 102 patients underwent hematopoietic stem cell transplant during the study period. Forty-nine (48%) received the neutropenic diet and 53 (52%) the BMT diet. Other than more males receiving the neutropenic diet (67% versus 47%, P = 0.05), there were no statistical demographic and outcome differences between the 2 groups. Additionally, 46 subjects (45%) completed the investigator-created questionnaire. There was no difference in the perceived food cravings, nausea, diet limitations, and subjective quality of life between the 2 cohorts. These data demonstrate noninferiority of the modified BMT diet over the traditional neutropenic diet. We believe the food safety-based diet offers a greater variety of food, which may assist in the transition to a normal diet.

Background: Dementia in people with intellectual disability (ID) is frequent but hard to recognise. Evidence-based recommendations for suitable instruments are lacking. Aims: The present study set out to evaluate informant-based dementia assessment instruments and to provide evidence-based recommendations for instruments most suitable in clinical practice and research. Method and procedures: A systematic review was conducted across ten international electronic databases. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines, including a risk of bias assessment, was applied to extract information and to evaluate measurement properties and the quality of available evidence. Outcomes and results: In total, 42 studies evaluating 18 informant-based assessment instruments were analysed. For screening purposes, we recommend the Behavioral and Psychological Symptoms of Dementia in Down Syndrome Scale (BPSD-DS), the Cognitive Scale for Down Syndrome (CS-DS), and the Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID). For a more thorough dementia assessment, we recommend the Cambridge Examination for Mental Disorders of Older People with Down's Syndrome and Others with Intellectual Disabilities (CAMDEX-DS). Conclusions and implications: Our study informs clinicians and researchers about adequate, well-evaluated dementia assessment instruments for people with ID, and highlights the need for high quality studies, especially regarding content validity.

Journal of molecular biology 433(16), 167015 (2021). doi:10.1016/j.jmb.2021.167015, Many bacteria export intracellular calcium using active transporters homologous to the sarco/endoplasmic reticulum Ca$^{2+}$-ATPase (SERCA). Here we present three crystal structures of Ca$^{2+}$-ATPase 1 from Listeria monocytogenes (LMCA1). Structures with BeF$^{-}_{3}$- mimicking a phosphoenzyme state reveal a closed state, which is intermediate between the outward-open E2P and the proton-occluded E2-P* conformations known for SERCA. It suggests that LMCA1 in the E2P state is pre-organized for dephosphorylation upon Ca$^{2+}$ release, consistent with the rapid dephosphorylation observed in single-molecule studies. An arginine side-chain occupies the position equivalent to calcium binding site I in SERCA, leaving a single Ca$^{2+}$ binding site in LMCA1, corresponding to SERCA site II. Observing no putative transport pathways dedicated to protons, we infer a direct proton counter transport through the Ca$^{2+}$ exchange pathways. The LMCA1 structures provide insight into the evolutionary divergence and conserved features of this important class of ion transporters., Published by Elsevier, Amsterdam [u.a.]

SARS-CoV-2 spike mRNA vaccines mediate protection from severe disease as early as 10 days post prime vaccination, when specific antibodies are hardly detectable and still lack neutralizing activity. Vaccine-induced T cells, especially CD8+ T cells, may thus be the main mediators of protection at this early stage. The details of antigen-specific CD8+ T cell induction after prime/boost vaccination, their comparison to naturally induced CD8+ T cell responses and their association with other arms of vaccine-induced adaptive immunity remain, however, incompletely understood. Here, we show on a single epitope level that both, a stable memory precursor pool of spike-specific CD8+ T cells and fully functional spike-specific effector CD8+ T cell populations, are vigorously mobilized as early as one week after prime vaccination when CD4+ T cell and spike-specific antibody responses are still weak and neutralizing antibodies are lacking. Boost vaccination after 3 weeks induced a full-fledged recall expansion generating highly differentiated CD8+ effector T cells, however, neither the functional capacity nor the memory precursor T cell pool was affected. Compared to natural infection, vaccine-induced early memory T cells exhibited similar frequencies and functional capacities but a different subset distribution dominated by effector memory T cells at the expense of self-renewing and multipotent central memory T cells. Our results indicate that spike-specific CD8+ T cells may represent the major correlate of early protection after SARS-CoV-2 mRNA/bnt162b2 prime vaccination that precede other effector arms of vaccine-induced adaptive immunity and are stably maintained after boost vaccination.

Potassium‐coupled chloride transporters (KCCs) play crucial roles in regulating cell volume and intracellular chloride concentration. They are characteristically inhibited under isotonic conditions via phospho‐regulatory sites located within the cytoplasmic termini. Decreased inhibitory phosphorylation in response to hypotonic cell swelling stimulates transport activity, and dysfunction of this regulatory process has been associated with various human diseases. Here, we present cryo‐EM structures of human KCC3b and KCC1, revealing structural determinants for phospho‐regulation in both N‐ and C‐termini. We show that phospho‐mimetic KCC3b is arrested in an inward‐facing state in which intracellular ion access is blocked by extensive contacts with the N‐terminus. In another mutant with increased isotonic transport activity, KCC1Δ19, this interdomain interaction is absent, likely due to a unique phospho‐regulatory site in the KCC1 N‐terminus. Furthermore, we map additional phosphorylation sites as well as a previously unknown ATP/ADP‐binding pocket in the large C‐terminal domain and show enhanced thermal stabilization of other CCCs by adenine nucleotides. These findings provide fundamentally new insights into the complex regulation of KCCs and may unlock innovative strategies for drug development., Cryo‐EM structures uncover phosphorylation‐dependent protein dynamics and ATP/ADP binding of human KCC membrane transporters.

Contains fulltext : 235822.pdf (Publisher’s version ) (Open Access) Auto-aggressive behaviour, especially treatment refractory suicidality in adolescents with psychiatric disorders, may be challenging to clinicians. In search of therapeutic possibilities, we have integrated current opinions regarding causality and interdependency of suicidality and auto-aggressive behaviour across disorders within the HiTOP framework. We propose a developmental model regarding these unsettling behaviours in youths that may help to guide future directions for research and interventions. We argue that the interdependent development of biologic factors, attachment, moral reasoning and emotion regulation in an overprotective environment may lead to social anxiety and later during development to emotion dysregulation and severe internalizing behaviour disorders. To optimize treatment efficacy for both internalizing and externalizing behaviour, we emphasize the importance transdiagnostic interventions, such as addressing non-compliance, restoration of trust between parents and their child, and limitation of avoidance behaviour. These may be seen as higher order interventions within the HiTOP framework.

MhsT of Bacillus halodurans is a transporter of hydrophobic amino acids and a homologue of the eukaryotic SLC6 family of Na+-dependent symporters for amino acids, neurotransmitters, osmolytes, or creatine. The broad range of transported amino acids by MhsT prompted the investigation of the substrate recognition mechanism. Here, we report six new substrate-bound structures of MhsT, which, in conjunction with functional studies, reveal how the flexibility of a Gly-Met-Gly (GMG) motif in the unwound region of transmembrane segment 6 (TM6) is central for the recognition of substrates of different size by tailoring the binding site shape and volume. MhsT mutants, harboring substitutions within the unwound GMG loop and substrate binding pocket that mimick the binding sites of eukaryotic SLC6A18/B0AT3 and SLC6A19/B0AT1 transporters of neutral amino acids, exhibited impaired transport of aromatic amino acids that require a large binding site volume. Conservation of a general (G/A/C)ΦG motif among eukaryotic members of SLC6 family suggests a role for this loop in a common mechanism for substrate recognition and translocation by SLC6 transporters of broad substrate specificity.

Acellular dermal matrices (ADM) were used to cover the implant to reduce implant rotations and to improve esthetic results. Current retrospective data on complication rates are heterogeneous. Prospective data are rare. Primary objective was to evaluate the explantation rate. 11 German sites, with experience in breast reconstruction using ADM, have been selected for participation in this study. Patients were enrolled according to predefined in- and exclusion criteria into two cohorts: group A - primary reconstruction and group B - secondary reconstruction after capsular contracture. After documentation of baseline characteristics and surgical parameters, endpoints such as rate of seroma, red breast syndrome, infection and explantation were assed at 1 day, 7 days, 1 month, 3, 6 and 12 months after surgery. In addition, patient- and surgeon-satisfaction were recorded. Data of 83 patients were analyzed (A: 50, B: 33). In 29 patients Epiflex was used bilaterally, so that it was used 112-times in total. The average age of the patient was 45.1 years (A: 41.5; B: 50.3), the average BMI was 22.2 (A: 22.3; B: 22.1). In total, 17.0 % seromas (A: 19.4 %; B: 12.5 %), 10.7 % red breast syndrome (A: 9.7 %; B: 12.5 %), 4.5 % infections (A: 6.9 %; B: 0 %) and 5.4 % explantations (A: 6.9 %; B: 2.5 %) were observed. During the average observation period of 8 month, the satisfaction of the patients and surgeons was high at all measured time points. On a scale from (1 - very satisfied to 6 - not satisfied) the satisfaction of patients and surgeons was 2.3 (A: 2.3; B:1.9) and 2.0 (A: 2.2; B: 1.8) respectively. Our data show, that both patients and surgeons are generally satisfied with the outcome of breast reconstruction using ADM. Complication rates were adequate and commonly lower in secondary reconstructions. Citation Format: Blohmer J-U, Ankel C, Faridi A, Krause-Bergmann B, Neumann C, Schnuppe K, Beier L, Mau C, Strittmatter H-J, Gerber-Schäfer C, Bauer L, Paepke S. First results of the NOGGO-AWOGyn observational study: Skin and nipple sparing mastectomy and breast reconstruction with an implant and Epiflex® [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-16-13.

Suicidality in adolescence is increasingly becoming a societal problem, especially because there remains a small group of patients in which treatment effectiveness is small. Existing formal guidelines often are of limited value in this group that often shows complex comorbidity.br/AIM: To contribute to the diagnostic and aetiological perspective in order to better understand therapy refractory internalising behaviour.br/METHOD: Integration of several scientific theoretical concepts into a holistic model.br/RESULTS: Evidence shows that suicidality should be considered within a broader scope of therapy refractory internalising behaviour. Important underpinnings comprise a partially overprotective parenting style, disturbed attachment processes and social anxiety. Internalising and externalising behaviour problems are viewed as expressions of avoidance behaviour. Furthermore, we discuss important implications for treatment.br/CONCLUSION: Applying an aetiological model for therapy refractory internalising behaviour may help to increase efficacy of treatment. Thus, transdiagnostic treatment can be offered, being less dependent on specific dsm-classifications. Focus of treatment is on restoration of basic trust between the youngster and his parents, and on ending avoidance behaviour that is based on social anxiety.

MhsT of Bacillus halodurans is a transporter of hydrophobic amino acids and a homologue of the eukaryotic SLC6 family of Na+-dependent symporters for amino acids, neurotransmitters, osmolytes, or creatine. The broad range of transported amino acids by MhsT prompted the investigation of the substrate recognition mechanism. Here, we report six new substrate-bound structures of MhsT, which, in conjunction with functional studies, reveal how the flexibility of a Gly-Met-Gly (GMG) motif in the unwound region of transmembrane segment 6 (TM6) is central for the recognition of substrates of different size by tailoring the binding site shape and volume. MhsT mutants, harboring substitutions within the unwound GMG loop and substrate binding pocket that mimick the binding sites of eukaryotic SLC6A18/B0AT3 and SLC6A19/B0AT1 transporters of neutral amino acids, exhibited impaired transport of aromatic amino acids that require a large binding site volume. Conservation of a general (G/A/C)ΦG motif among eukaryotic members of SLC6 family suggests a role for this loop in a common mechanism for substrate recognition and translocation by SLC6 transporters of broad substrate specificity.

Tuberculosis is currently the single most deadly infectious disease in the world and a public health priority as defined by WHO. Although the disease is in general curable, treatment success is hampered by the necessity of a long and side effect prone treatment. Low treatment efficiency may be partly due to the special growth states that mycobacteria enter to avoid being killed by antibiotics and to persist longer within the host. Such growth states have been recently defined as dormant or persistent. We produced dormant model-organism cultures using an acidification model and characterized those by a multilayered approach using mass spectrometry (MALDI-TOF), microscopy (SEM, Raman), and microbiological techniques (CFU, OD600, ATP-levels). With a fast and 96-well-adapted extraction protocol, mycobacteria could be inactivated and extracted for MALDI-TOF analysis. For the first time, we demonstrate growth-state-dependent changes in the mass signatures of the culture, allowing for a reliable differentiation of dormant state and exponential growth. We also demonstrate resuscitation from dormant state back to exponential growth. Viable mycobacteria were immobilized, and single organisms were analyzed individually by Raman microscopy. For single-cell Raman microscopy, Mycobacterium smegmatis cultures were fixed using a new fast and gentle single-step immobilization technique on a hydrophobic glass slide. We were able to distinguish single viable bacteria in the dormant state from their rapidly growing, genetically identical counterparts, identifying the growth state of the culture based on single-organism spectra. This allows for the separation of heterogeneous cultures depending on their growth state using the destruction-free optical method of Raman microscopy.

Zusammenfassung Hintergrund Tumoren im Bereich der ableitenden Tränenwege (TNW) sind selten. Inflammatorische Pseudotumoren stellen keine Neoplasien im eigentlichen Sinne dar. Aufgrund einer chronischen Entzündung kann es zur Ausbildung von angiomatösen Granulationsgeweben kommen. Patienten Die 1. Kasuistik handelt von einem 53-jährigen Patienten, der nach abgelaufener akuter Dakryozystitis eine persistierende Raumforderung im Bereich der mediokaudalen Orbita aufwies. Mittels diagnostischer Dakryoendoskopie wurde ein großer Dakryolith detektiert. In der anschließend durchgeführten transkutanen Dakryozystorhinostomie (DZR) konnte dieser sowie polypöses Gewebe der Tränensackschleimhaut entfernt werden. Die 2. Kasuistik beschreibt eine 29-jährige Patientin, die 7 Jahre zuvor eine transkanalikuläre TNW-Chirurgie mit Intubation von Silikonstützmaterial erhalten hatte. Anamnestisch bestanden chronisch-rezidivierende mukopurulente Sekretionen sowie eine ausgeprägte Druckschmerzhaftigkeit des Tränensacks. Eine diagnostische Dakryoendoskopie erbrachte den Nachweis von intrasakkal verbliebenem Silikonmaterial. Über eine DZR wurde der Fremdkörper entfernt. Es zeigte sich ferner eine die gesamten ableitenden Tränenwege ausfüllende, polypöse Raumforderung. Ergebnisse Bei beiden Patienten erfolgte eine komplikationslose DZR. Im Rahmen der OP gelang es, den Ductus nasolacrimalis zu rekonstruieren. Die TNW wurden durch den Einsatz von monokanalikulonasalen Intubationen (Kasuistik 1 und 2) sowie einer zusätzlichen Intubation in die Osteotomie (Kasuistik 2) vorübergehend geschient. Histologisch stellte sich bei beiden Patienten ein reaktiver Granulationsgewebspolyp dar. Im postoperativen Verlauf von 9 (Patient 1) bzw. 12 (Patient 2) Monaten waren beide Patienten vollkommen beschwerdefrei, die TNW-Stützmaterialien konnten komplikationslos und vollständig entfernt werden. Schlussfolgerungen Dakryolithen und intrasakkal verbliebene iatrogene Fremdkörper verursachen eine chronische Dakryozystitis. Im Rahmen der Entzündungsreaktion kann es zu einer reaktiven Gewebsneubildung kommen. Es handelt sich hierbei um hypertrophe granulierende Entzündungen. Endogene (Dakryolithen) und exogene (iatrogene Fremdkörper) Noxen sind mögliche zugrunde liegende Auslöser. Die histologische Diagnostik zum Ausschluss anderer entzündlicher Ursachen sowie von Neoplasien ist essenziell.