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Recording and manipulating neuronal ensemble activity is a key requirement in advanced neuromodulatory and behavior studies. Devices capable of both recording and manipulating neuronal activity brain-computer interfaces (BCIs) should ideally operate un-tethered and allow chronic longitudinal manipulations in the freely moving animal. In this study, we designed a new intracortical BCI feasible of telemetric recording and stimulating local gray and white matter of visual neural circuit after irradiation exposure. To increase the translational reliance, we put forward a Göttingen minipig model. The animal was stereotactically irradiated at the level of the visual cortex upon defining the target by a fused cerebral MRI and CT scan. A fully implantable neural telemetry system consisting of a 64 channel intracortical multielectrode array, a telemetry capsule, and an inductive rechargeable battery was then implanted into the visual cortex to record and manipulate local field potentials, and multi-unit activity. We achieved a 3-month stability of the functionality of the un-tethered BCI in terms of telemetric radio-communication, inductive battery charging, and device biocompatibility for 3 months. Finally, we could reliably record the local signature of sub- and suprathreshold neuronal activity in the visual cortex with high bandwidth without complications. The ability to wireless induction charging combined with the entirely implantable design, the rather high recording bandwidth, and the ability to record and stimulate simultaneously put forward a wireless BCI capable of long-term un-tethered real-time communication for causal preclinical circuit-based closed-loop interventions., Competing Interests: MBS and JRA are employees of Zap Surgical Systems, Inc., that funded this study, own stock, and have patents in the field of stereotactic radiosurgery without affecting the trial’s outcome. AD, QF, VG, and JM were employees of Triangle BioSystems International as a division of Harvard Bioscience Inc., however, did not have any influence on the result of the experiments. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zaer, Deshmukh, Orlowski, Fan, Prouvot, Glud, Jensen, Worm, Lukacova, Mikkelsen, Fitting, Adler, Schneider, Jensen, Fu, Go, Morizio, Sørensen and Stroh.)

Background: Stereotaxic neurosurgery in large animals is used widely in different sophisticated models, where precision is becoming more crucial as desired anatomical target regions are becoming smaller. Individually calculated coordinates are necessary in large animal models with cortical and subcortical anatomical differences., New Method: We present a convenient method to make an MRI-visible skull fiducial for 3D MRI-based stereotaxic procedures in larger experimental animals. Plastic screws were filled with either copper-sulfate solution or MRI-visible paste from a commercially available cranial head marker. The screw fiducials were inserted in the animal skulls and T1 weighted MRI was performed allowing identification of the inserted skull marker., Results: Both types of fiducial markers were clearly visible on the MRÍs. This allows high precision in the stereotaxic space., Comparison With Existing Method: The use of skull bone based fiducial markers gives high precision for both targeting and evaluation of stereotaxic systems. There are no metal artifacts and the fiducial is easily removed after surgery., Conclusion: The fiducial marker can be used as a very precise reference point, either for direct targeting or in evaluation of other stereotaxic systems., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Postmenopausal women in the Western world are highly burdened by osteoporotic fractures. The aim of this study is to investigate risk factors at baseline for fracture in 6416 postmenopausal women during long-term follow-up. At baseline, all women completed a questionnaire regarding background factors, diseases, current use of medications and reproductive and contraceptive history, a physical examination and laboratory analyses. Fracture occurrence after inclusion in the study was recorded with the help of official registries. All significant variables in univariate logistic regression with a decreased or increased risk for fracture were analysed in a multivariate logistic regression. Increased fracture risk was observed in women currently using proton pump inhibitors (PPI), odds ratio (OR) 2.53 (95% confidence interval (CI)) 1.28-4.99, and women having had a fracture after the age of 40, but before inclusion in the study, OR 1.70 (95% CI 1.24-2.32). A protective effect against fractures was observed in women with a positive family history of diabetes OR 0.66 (95% CI 0.44-0.98). A significant interaction was observed between fracture risk, use of PPI and HT status (p=0.014) and women with HT had an increased fracture risk with use of PPI (OR 3.37 (95% CI 1.96-5.80)) compared to women without HT (OR 1.13 (95% CI 0.57-2.24)). In conclusion, usage of PPIs was associated with a doubled risk for fracture in postmenopausal women. Women with previous fractures using PPI should be considered for prophylactic treatment reducing fracture risk., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)