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1.
NEJM Evid ; 3(1): EVIDoa2300235, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38320511

ABSTRACT

BACKGROUND: Rivaroxaban and dabigatran were not superior to aspirin in trials of patients with embolic stroke of undetermined source (ESUS). It is unknown whether apixaban is superior to aspirin in patients with ESUS and known risk factors for cardioembolism. METHODS: We conducted a multicenter, randomized, open-label, blinded-outcome trial of apixaban (5 mg twice daily) compared with aspirin (100 mg once daily) initiated within 28 days after ESUS in patients with at least one predictive factor for atrial fibrillation or a patent foramen ovale. Cardiac monitoring was mandatory, and aspirin treatment was switched to apixaban in case of atrial fibrillation detection. The primary outcome was any new ischemic lesion on brain magnetic resonance imaging (MRI) during 12-month follow-up. Secondary outcomes included major and clinically relevant nonmajor bleeding. RESULTS: A total of 352 patients were randomly assigned to receive apixaban (178 patients) or aspirin (174 patients) at a median of 8 days after ESUS. At 12-month follow-up, MRI follow-up was available in 325 participants (92.3%). New ischemic lesions occurred in 23 of 169 (13.6%) participants in the apixaban group and in 25 of 156 (16.0%) participants in the aspirin group (adjusted odds ratio, 0.79; 95% confidence interval, 0.42 to 1.48; P=0.57). Major and clinically relevant nonmajor bleeding occurred in five and seven participants, respectively (1-year cumulative incidences, 2.9 and 4.2; hazard ratio, 0.68; 95% confidence interval, 0.22 to 2.16). Serious adverse event rates were 43.9 per 100 person-years in those given apixaban and 45.7 per 100 person-years in those given aspirin. The Apixaban for the Treatment of Embolic Stroke of Undetermined Source trial was terminated after a prespecified interim analysis as a result of futility. CONCLUSIONS: Apixaban treatment was not superior to cardiac monitoring-guided aspirin in preventing new ischemic lesions in an enriched ESUS population. (Funded by Bristol-Myers Squibb and Medtronic Europe; ClinicalTrials.gov number, NCT02427126.)


Subject(s)
Embolic Stroke , Pyrazoles , Pyridones , Stroke , Humans , Aspirin , Double-Blind Method , Stroke/prevention & control
2.
Neuromodulation ; 27(3): 565-571, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37804281

ABSTRACT

OBJECTIVES: Deep brain stimulation (DBS) is a well-established surgical therapy for movement disorders that comprises implantation of stimulation electrodes and a pacemaker. These procedures can be performed separately, leaving the possibility of externalizing the electrodes for local field potential recording or testing multiple targets for therapeutic efficacy. It is still debated whether the temporary externalization of DBS electrodes leads to an increased risk of infection. We therefore aimed to assess the risk of infection during and after lead externalization in DBS surgery. MATERIALS AND METHODS: In this retrospective study, we analyzed a consecutive series of 624 DBS surgeries, including 266 instances with temporary externalization of DBS electrodes for a mean of 6.1 days. Patients were available for follow-up of at least one year, except in 15 instances. In 14 patients with negative test stimulation, electrodes were removed. All kinds of infections related to implantation of the neurostimulation system were accounted for. RESULTS: Overall, infections occurred in 22 of 624 surgeries (3.5%). Without externalization of electrodes, infections were noted after 7 of 358 surgeries (2.0%), whereas with externalization, 15 of 252 infections were found (6.0%). This difference was significant (p = 0.01), but it did not reach statistical significance when comparing groups within different diagnoses. The rate of infection with externalized electrodes was highest in psychiatric disorders (9.1%), followed by Parkinson's disease (7.3%), pain (5.7%), and dystonia (5.5%). The duration of the externalization of the DBS electrodes was comparable in patients who developed an infection (6.1 ± 3.1 days) with duration in those who did not (6.0 ± 3.5 days). CONCLUSIONS: Although infection rates were relatively low in our study, there was a slightly higher infection rate when DBS electrodes were externalized. On the basis of our results, the indication for electrode externalization should be carefully considered, and patients should be informed about the possibility of a higher infection risk when externalization of DBS electrodes is planned.


Subject(s)
Deep Brain Stimulation , Infections , Parkinson Disease , Humans , Deep Brain Stimulation/adverse effects , Deep Brain Stimulation/methods , Retrospective Studies , Electrodes, Implanted/adverse effects , Parkinson Disease/therapy , Infections/epidemiology , Infections/etiology
3.
J Neurosurg ; : 1-9, 2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37922545

ABSTRACT

OBJECTIVE: Functional stereotactic neurosurgery including deep brain stimulation (DBS) and radiofrequency lesioning is well established and widely used for treatment of movement disorders and various other neurological and psychiatric diseases. Although functional stereotactic neurosurgery procedures are considered relatively safe, intracranial hemorrhage resulting in permanent neurological deficits may occur in 1%-3% of patients. Microelectrode recording (MER) has been recognized as a valuable tool for refining the final target in functional stereotactic neurosurgery. Moreover, MER provides insight into the underlying neurophysiological pathomechanisms of movement disorders and other diseases. Nevertheless, there is an ongoing controversy on whether MER increases the risk for hemorrhage. The authors aimed to compare the risk of hemorrhage in functional stereotactic neurosurgical procedures with regard to the use of MER. METHODS: The authors performed a comparative analysis on a consecutive series of 645 functional neurosurgery procedures, including 624 DBS surgeries and 21 radiofrequency lesionings, to evaluate whether the use of MER would increase the risk for hemorrhage. MER was performed in 396 procedures, while no MER was used in 249 cases. The MER technique involved the use of a guiding cannula and a single trajectory when feasible. Postoperative CT scans were obtained within 24 hours after surgery in all patients and screened for the presence of hemorrhage. RESULTS: Twenty-one intracranial hemorrhages were detected on the postoperative CT scans (3.2%). Of the 21 intracranial hemorrhages, 14 were asymptomatic and 7 were symptomatic. Symptoms were transient except in 1 case. There was no statistically significant correlation between hemorrhage and the use of MER at any site (subdural, ventricle, trajectory, target, whether asymptomatic or symptomatic). There were 4 cases of symptomatic hemorrhage in the MER group (1%) and 3 cases in those without MER (1.2%). CONCLUSIONS: Intraoperative MER did not increase the overall risk of hemorrhage in the authors' experience using primarily a single MER trajectory and a guiding cannula.

4.
Plant Direct ; 7(8): e519, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37600238

ABSTRACT

With ongoing climate change and the increase in extreme weather events, especially droughts, the challenge of maintaining food security is becoming ever greater. Locally adapted landraces of crops represent a valuable source of adaptation to stressful environments. In the light of future droughts-both by altered soil water supply and increasing atmospheric water demand (vapor pressure deficit [VPD])-plants need to improve their water efficiency. To do so, plants can enhance their access to soil water by improving rhizosphere hydraulic conductivity via the exudation of mucilage. Furthermore, plants can reduce transpirational water loss via stomatal regulation. Although the role of mucilage and stomata regulation on plant water management have been extensively studied, little is known about a possible coordination between root mucilage properties and stomatal sensitivity as well as abiotic drivers shaping the development of drought resistant trait suits within landraces. Mucilage properties and stomatal sensitivity of eight Mexican landraces of Zea mays in contrast with one inbred line were first quantified under controlled conditions and second related to water demand and supply at their respective site of origin. Mucilage physical properties-namely, viscosity, contact angle, and surface tension-differed between the investigated maize varieties. We found strong influences of precipitation seasonality, thus plant water availability, on mucilage production (R 2 = .88, p < .01) and mucilage viscosity (R 2 = .93, p < .01). Further, stomatal sensitivity to increased atmospheric water demand was related to mucilage viscosity and contact angle, both of which are crucial in determining mucilage's water repellent, thus maladaptive, behavior upon soil drying. The identification of landraces with pre-adapted suitable trait sets with regard to drought resistance is of utmost importance, for example, trait combinations such as exhibited in one of the here investigated landraces. Our results suggest a strong environmental selective force of seasonality in plant water availability on mucilage properties as well as regulatory stomatal effects to avoid mucilage's maladaptive potential upon drying and likely delay critical levels of hydraulic dysfunction. By this, landraces from highly seasonal climates may exhibit beneficial mucilage and stomatal traits to prolong plant functioning under edaphic drought. These findings may help breeders to efficiently screen for local landraces with pre-adaptations to drought to ultimately increase crop yield resistance under future climatic variability.

6.
Biomedicines ; 11(3)2023 Mar 09.
Article in English | MEDLINE | ID: mdl-36979814

ABSTRACT

Immune reactions are characterized by the rapid immigration of phagocytes into sites of inflammation. Meticulous regulation of these migratory processes is crucial for preventing uncontrolled and harmful phagocyte extravasation. S100A8/S100A9 is the major calcium-binding protein complex expressed in phagocytes. After release, this complex acts as a proinflammatory alarmin in the extracellular space, but the intracellular functions of these highly abundant proteins are less clear. Results of this study reveal an important role of S100A8/S100A9 in coordinated cytoskeleton rearrangement during migration. We found that S100A8/S100A9 was able to cross-link F-actin and microtubules in a calcium- and phosphorylation-dependent manner. Cells deficient in S100A8/S100A9 showed abnormalities in cell adhesion and motility. Missing cytoskeletal interactions of S100A8/S100A9 caused differences in the surface expression and activation of ß1-integrins as well as in the regulation of Src/Syk kinase family members. Loss of S100A8/S100A9 led to dysregulated integrin-mediated adhesion and migration, resulting in an overall higher dynamic activity of non-activated S100A8/S100A9-deficient phagocytes. Our data suggest that intracellular S100A8/S100A9 is part of a novel regulatory mechanism that ensures the precise control necessary to facilitate the change between the quiescent and activated state of phagocytes.

7.
Genet Med ; 24(10): 2079-2090, 2022 10.
Article in English | MEDLINE | ID: mdl-35986737

ABSTRACT

PURPOSE: Biallelic variants in UCHL1 have been associated with a progressive early-onset neurodegenerative disorder, autosomal recessive spastic paraplegia type 79. In this study, we investigated heterozygous UCHL1 variants on the basis of results from cohort-based burden analyses. METHODS: Gene-burden analyses were performed on exome and genome data of independent cohorts of patients with hereditary ataxia and spastic paraplegia from Germany and the United Kingdom in a total of 3169 patients and 33,141 controls. Clinical data of affected individuals and additional independent families were collected and evaluated. Patients' fibroblasts were used to perform mass spectrometry-based proteomics. RESULTS: UCHL1 was prioritized in both independent cohorts as a candidate gene for an autosomal dominant disorder. We identified a total of 34 cases from 18 unrelated families, carrying 13 heterozygous loss-of-function variants (15 families) and an inframe insertion (3 families). Affected individuals mainly presented with spasticity (24/31), ataxia (28/31), neuropathy (11/21), and optic atrophy (9/17). The mass spectrometry-based proteomics showed approximately 50% reduction of UCHL1 expression in patients' fibroblasts. CONCLUSION: Our bioinformatic analysis, in-depth clinical and genetic workup, and functional studies established haploinsufficiency of UCHL1 as a novel disease mechanism in spastic ataxia.


Subject(s)
Cerebellar Ataxia , Optic Atrophy , Spastic Paraplegia, Hereditary , Spinocerebellar Ataxias , Ubiquitin Thiolesterase , Ataxia/genetics , Cerebellar Ataxia/genetics , Humans , Loss of Function Mutation , Muscle Spasticity/genetics , Mutation , Optic Atrophy/genetics , Pedigree , Spastic Paraplegia, Hereditary/genetics , Spinocerebellar Ataxias/genetics , Ubiquitin Thiolesterase/genetics
8.
NPJ Vaccines ; 7(1): 76, 2022 Jul 05.
Article in English | MEDLINE | ID: mdl-35790739

ABSTRACT

We present the long-term outcomes of 44 patients who developed cerebral venous sinus thrombosis after vaccination with the adenoviral vector ChAdOx1 nCoV-19 COVID-19 vaccine. Assessment of the Extended Glasgow Outcome Scale was performed within 3-6 months after the initial hospital admissions. Patient outcomes ranged from good recovery (13 patients, 29.6%) to moderate disability (11 patients, 25.0%) and severe disability or vegetative state (6 patients, 13.6%). Fatal outcomes were reported in 14 patients (31.8%).

9.
Oper Neurosurg (Hagerstown) ; 23(2): e108-e113, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35838461

ABSTRACT

BACKGROUND: Deep brain stimulation (DBS) surgery has advanced tremendously, for both clinical applications and technology. Although DBS surgery is an overall safe procedure, rare side effects, in particular, hemorrhage, may result in devastating consequences. Although there are certain advantages with transventricular trajectories, it has been reasoned that avoidance of such trajectories would likely reduce hemorrhage. OBJECTIVE: To investigate the possible impact of a transventricular trajectory as compared with a transcerebral approach on the occurrence of symptomatic and asymptomatic hemorrhage after DBS electrode placement. METHODS: Retrospective evaluation of 624 DBS surgeries in 582 patients, who underwent DBS surgery for movement disorders, chronic pain, or psychiatric disorders. A stereotactic guiding cannula was routinely used for DBS electrode insertion. All patients had postoperative computed tomography scans within 24 hours after surgery. RESULTS: Transventricular transgression was identified in 404/624 DBS surgeries. The frequency of hemorrhage was slightly higher in transventricular than in transcerebral DBS surgeries (15/404, 3.7% vs 6/220, 2.7%). While 7/15 patients in the transventricular DBS surgery group had a hemorrhage located in the ventricle, 6 had an intracerebral hemorrhage along the electrode trajectory unrelated to transgression of the ventricle and 2 had a subdural hematoma. Among the 7 patients with a hemorrhage located in the ventricle, only one became symptomatic. Overall, a total of 7/404 patients in the transventricular DBS surgery group had a symptomatic hemorrhage, whereas the hemorrhage remained asymptomatic in all 6/220 patients in the transcerebral DBS surgery group. CONCLUSION: Transventricular approaches in DBS surgery can be performed safely, in general, when special precautions such as using a guiding cannula are routinely applied.


Subject(s)
Deep Brain Stimulation , Movement Disorders , Cerebral Hemorrhage/diagnostic imaging , Cerebral Hemorrhage/etiology , Cerebral Hemorrhage/surgery , Deep Brain Stimulation/adverse effects , Deep Brain Stimulation/methods , Electrodes, Implanted/adverse effects , Humans , Movement Disorders/etiology , Retrospective Studies
10.
Front Neurol ; 13: 1076713, 2022.
Article in English | MEDLINE | ID: mdl-36712453

ABSTRACT

Objectives: Tardive dystonia/dyskinesia (TDD) occurs as a side effect of anti-dopaminergic drugs, including metoclopramide, and is often refractory to medication. While pallidal deep brain stimulation (DBS) has become an accepted treatment for TDD secondary to neuroleptic medication, there is much less knowledge about its effects on metoclopramide-induced TDD. Methods: We present the case of a woman with metoclopramide-induced TDD, whose symptoms were initially misjudged as "functional." After 8 years of ineffective medical treatments, she received bilateral implantation of quadripolar electrodes into the posteroventral lateral globus pallidus internus (GPi). Results: GPi DBS led to significant symptom reduction [Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) motor score 24/44 at admission and 7/44 at discharge]. Chronic stimulation led to full recovery from TDD symptoms 9 years after surgery. The BFMDRS motor score decreased to 0.5 (98% improvement). Discussion: Pallidal DBS may result in sustained improvement of TDD secondary to chronic metoclopramide intake in the long term.

11.
J Clin Med ; 10(19)2021 Oct 02.
Article in English | MEDLINE | ID: mdl-34640598

ABSTRACT

Cervical artery dissection (CAD) is a frequent cause of stroke in young adults. Previous studies investigating the efficiency of anticoagulation (AC) versus antiplatelet therapy (AT) found an insignificant difference. We therefore retrospectively evaluated a combination of AC plus AT in patients with acute CAD regarding safety and efficacy. Twenty-eight patients with CAD and minor neurological symptoms/no major infarction received either single (n = 14) or dual AT (n = 14) combined with AC. Angiographic follow-up during hospitalization, 4-8 weeks and 3-6 months after CAD focused on occlusion, residual stenosis, and functional recanalization. Possible adverse events were surveyed. We compared the AC plus AT group to 22 patients with acute CAD treated with AC or AT. Compared to preceding AC-/AT-only studies, AC plus single or dual AT resulted in more frequent, faster recanalization. Frequency and severity of adverse events was comparable. No major adverse events or death occurred. Preceding works on conservative treatment of CAD are discussed and compared to this study. Considerations are given to pathophysiology and the dynamic of CAD. Combining AC plus AT in CAD may result in more reliable recanalization in a shorter time. The risk for adverse events appears similar to treatment with only AC or AT.

12.
Acta Neurochir (Wien) ; 163(10): 2825-2831, 2021 10.
Article in English | MEDLINE | ID: mdl-34342730

ABSTRACT

BACKGROUND: In the aging society, many patients with movement disorders, pain syndromes, or psychiatric disorders who are candidates for deep brain stimulation (DBS) surgery suffer also from cardiovascular co-morbidities that require chronic antiplatelet or anticoagulation treatment. Because of a presumed increased risk of intracranial hemorrhage during or after surgery and limited knowledge about perioperative management, chronic antiplatelet or anticoagulation treatment often has been considered a relative contraindication for DBS. Here, we evaluate whether or not there is an increased risk for intracranial hemorrhage or thromboembolic complications in patients on chronic treatment (paused for surgery or bridged with subcutaneous heparin) as compared to those without. METHODS: Out of a series of 465 patients undergoing functional stereotactic neurosurgery, 34 patients were identified who were on chronic treatment before and after receiving DBS. In patients with antiplatelet treatment, medication was stopped in the perioperative period. In patients with vitamin K antagonists or novel oral anticoagulants (NOACs), heparin was used for bridging. All patients had postoperative stereotactic CT scans, and were followed up for 1 year after surgery. RESULTS: In patients on chronic antiplatelet or anticoagulation treatment, intracranial hemorrhage occurred in 2/34 (5.9%) DBS surgeries, whereas the rate of intracranial hemorrhage was 15/431 (3.5%) in those without, which was statistically not significant. Implantable pulse generator pocket hematomas were seen in 2/34 (5.9%) surgeries in patients on chronic treatment and in 4/426 (0.9%) without. There were only 2 instances of thromboembolic complications which both occurred in patients without chronic treatment. There were no hemorrhagic complications during follow-up for 1 year. CONCLUSIONS: DBS surgery in patients on chronic antiplatelet or anticoagulation treatment is feasible. Also, there was no increased risk of hemorrhage in the first year of follow-up after DBS surgery. Appropriate patient selection and standardized perioperative management are necessary to reduce the risk of intracranial hemorrhage and thromboembolic complications.


Subject(s)
Deep Brain Stimulation , Administration, Oral , Anticoagulants/adverse effects , Hemorrhage , Humans , Platelet Aggregation Inhibitors/adverse effects
13.
Article in English | MEDLINE | ID: mdl-34434608

ABSTRACT

Introduction: Deep brain stimulation (DBS) has become an accepted treatment for inherited and idiopathic dystonia but less so for acquired dystonia. Patients benefit from long-term improvement with chronic DBS. Prolonged benefit over months has even been reported after cessation of stimulation on long-term follow-up. Case report: We report a case of a 25-year-old man with acquired dystonia who had sustained symptom improvement despite battery depletion after 6.5 years of chronic bilateral thalamic and pallidal DBS. Discussion: We posit that chronic pallidal DBS can be a genuine disease-modifying treatment in single patients with dystonia with regard to its long-term effect even after prolonged discontinuation. Highlights: Chronic deep brain stimulation (DBS) is an approved treatment for idiopathic and inherited dystonia. During the early course of chronic stimulation, cessation of DBS due to battery depletion results in rapid worsening of symptoms and rapid battery replacement is required. Few reports of sustained symptom relief in idiopathic dystonia have been published. We report a case of sustained symptom relief in acquired dystonia after DBS cessation which likely reflects neuroplasticity changes with a disease-modifying impact.


Subject(s)
Deep Brain Stimulation , Dystonia , Dystonic Disorders , Adult , Dystonia/therapy , Dystonic Disorders/therapy , Globus Pallidus , Humans , Male
14.
J Neural Transm (Vienna) ; 128(8): 1205-1213, 2021 08.
Article in English | MEDLINE | ID: mdl-34231038

ABSTRACT

BACKGROUND: Deep brain stimulation (DBS) of the globus pallidus internus (GPi) has become an accepted treatment for severe cervical dystonia (CD). Assessment of therapeutic efficacy of DBS mostly focused on head position at rest but hardly on limitations of head and neck mobility, which represent a functionally important impairment in CD. OBJECTIVE: We aimed to determine prospectively head and neck range of motion (ROM) preoperatively and during chronic bilateral GPi DBS in a series of 11 patients with idiopathic CD or segmental dystonia with prominent CD using a computerized motion analysis. METHODS: Maximum horizontal rotation of the head in the transverse plane and lateral inclination in the frontal plane were measured preoperatively and at a median of 7 months of chronic GPi DBS, using an ultrasound-based three-dimensional measuring system combined with surface electromyography of cervical muscles. RESULTS: Horizontal rotation of the head increased from 78.8° ± 31.5° (mean ± SD) preoperatively to 100.7° ± 24.7° with GPi DBS (p < 0.01), thereby improvement of head rotation to the anti-dystonic side (+ 14,2° ± 12,2°) was greater than to the pro-dystonic side (+ 7,8° ± 9,2°; p < 0.05). Movement-related agonistic-antagonistic EMG modulation during head rotation was enhanced with GPi DBS in both sternocleidomastoid (modulation index (MI) 35.8% ± 26.7% preoperatively vs. 67.3% ± 16.9% with GPi DBS, p < 0.01), and splenius capitis muscles (MI 1.9% ± 24.5% preoperatively vs. 44.8% ± 11.6% with GPi DBS, p < 0.01). CONCLUSION: Chronic bilateral GPi DBS significantly improves head ROM in CD, likely due to enhanced agonist-antagonist EMG activity with reduced co-contraction. Computerized motion analysis provides an objective measurement to assess the improvement of head and neck mobility in CD.


Subject(s)
Deep Brain Stimulation , Torticollis , Globus Pallidus , Humans , Range of Motion, Articular , Torticollis/therapy , Treatment Outcome
15.
Biomedicines ; 9(7)2021 Jun 25.
Article in English | MEDLINE | ID: mdl-34202202

ABSTRACT

Introduction: The treatment of neuropathic and central pain still remains a major challenge. Thalamic deep brain stimulation (DBS) involving various target structures is a therapeutic option which has received increased re-interest. Beneficial results have been reported in several more recent smaller studies, however, there is a lack of prospective studies on larger series providing long term outcomes. Methods: Forty patients with refractory neuropathic and central pain syndromes underwent stereotactic bifocal implantation of DBS electrodes in the centromedian-parafascicular (CM-Pf) and the ventroposterolateral (VPL) or ventroposteromedial (VPM) nucleus contralateral to the side of pain. Electrodes were externalized for test stimulation for several days. Outcome was assessed with five specific VAS pain scores (maximum, minimum, average pain, pain at presentation, allodynia). Results: The mean age at surgery was 53.5 years, and the mean duration of pain was 8.2 years. During test stimulation significant reductions of all five pain scores was achieved with either CM-Pf or VPL/VPM stimulation. Pacemakers were implanted in 33/40 patients for chronic stimulation for whom a mean follow-up of 62.8 months (range 3-180 months) was available. Of these, 18 patients had a follow-up beyond four years. Hardware related complications requiring secondary surgeries occurred in 11/33 patients. The VAS maximum pain score was improved by ≥50% in 8/18, and by ≥30% in 11/18 on long term follow-up beyond four years, and the VAS average pain score by ≥50% in 10/18, and by ≥30% in 16/18. On a group level, changes in pain scores remained statistically significant over time, however, there was no difference when comparing the efficacy of CM-Pf versus VPL/VPM stimulation. The best results were achieved in patients with facial pain, poststroke/central pain (except thalamic pain), or brachial plexus injury, while patients with thalamic lesions had the least benefit. Conclusion: Thalamic DBS is a useful treatment option in selected patients with severe and medically refractory pain.

16.
Haematologica ; 106(8): 2170-2179, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34011137

ABSTRACT

The COVID-19 pandemic has resulted in significant morbidity and mortality worldwide. To prevent severe infection, mass COVID-19 vaccination campaigns with several vaccine types are currently underway. We report pathological and immunological findings in 8 patients who developed vaccine-induced immune thrombotic thrombocytopenia (VITT) after administration of SARS-CoV-2 vaccine ChAdOx1 nCoV-19. We analyzed patient material using enzyme immune assays, flow cytometry and heparin-induced platelet aggregation assay and performed autopsies on two fatal cases. Eight patients (5 female, 3 male) with a median age of 41.5 years (range, 24 to 53) were referred to us with suspected thrombotic complications 6 to 20 days after ChAdOx1 nCoV-19 vaccination. All patients had thrombocytopenia at admission. Patients had a median platelet count of 46.5 x109/L (range, 8 to 92). Three had a fatal outcome and 5 were successfully treated. Autopsies showed arterial and venous thromboses in various organs and the occlusion of glomerular capillaries by hyaline thrombi. Sera from VITT patients contain high titer antibodies against platelet factor 4 (PF4) (OD 2.59±0.64). PF4 antibodies in VITT patients induced significant increase in procoagulant markers (P-selectin and phosphatidylserine externalization) compared to healthy volunteers and healthy vaccinated volunteers. The generation of procoagulant platelets was PF4 and heparin dependent. We demonstrate the contribution of antibody-mediated platelet activation in the pathogenesis of VITT.


Subject(s)
COVID-19 , Thrombocytopenia , Adult , Autoantibodies , Blood Platelets , COVID-19 Vaccines , ChAdOx1 nCoV-19 , Female , Humans , Male , Middle Aged , Pandemics , SARS-CoV-2 , Thrombocytopenia/chemically induced , Vaccination/adverse effects , Young Adult
17.
J Clin Med ; 10(8)2021 Apr 09.
Article in English | MEDLINE | ID: mdl-33918932

ABSTRACT

BACKGROUND: As of 8 April 2021, a total of 2.9 million people have died with or from the coronavirus infection causing COVID-19 (Corona Virus Disease 2019). On 29 January 2021, the European Medicines Agency (EMA) approved a COVID-19 vaccine developed by Oxford University and AstraZeneca (AZD1222, ChAdOx1 nCoV-19, COVID-19 vaccine AstraZeneca, Vaxzevria, Covishield). While the vaccine prevents severe course of and death from COVID-19, the observation of pulmonary, abdominal, and intracranial venous thromboembolic events has raised concerns. OBJECTIVE: To describe the clinical manifestations and the concerning management of patients with cranial venous sinus thrombosis following first exposure to the "COVID-19 vaccine AstraZeneca". METHODS: Patient files, laboratory findings, and diagnostic imaging results, and endovascular interventions of three concerning patients were evaluated in retrospect. RESULTS: Three women with intracranial venous sinus thrombosis after their first vaccination with "COVID-19 vaccine AstraZeneca" were encountered. Patient #1 was 22 years old and developed headaches four days after the vaccination. On day 7, she experienced a generalized epileptic seizure. Patient #2 was 46 years old. She presented with severe headaches, hemianopia to the right, and mild aphasia 13 days after the vaccination. MRI showed a left occipital intracerebral hemorrhage. Patient #3 was 36 years old and presented 17 days after the vaccination with acute somnolence and right-hand hemiparesis. The three patients were diagnosed with extensive venous sinus thrombosis. They were managed by heparinization and endovascular recanalization of their venous sinuses. They shared similar findings: elevated levels of D-dimers, platelet factor 4 antiplatelet antibodies, corona spike protein antibodies, combined with thrombocytopenia. Under treatment with low-molecular-weight heparin, platelet counts normalized within several days. CONCLUSION: Early observations insinuate that the exposure to the "COVID-19 vaccine AstraZeneca" might trigger the expression of antiplatelet antibodies, resulting in a condition with thrombocytopenia and venous thrombotic events (e.g., intracranial venous sinus thrombosis). These patients' treatment should address the thrombo-embolic manifestations, the coagulation disorder, and the underlying immunological phenomena.

18.
J Allergy Clin Immunol ; 146(5): 1137-1151, 2020 11.
Article in English | MEDLINE | ID: mdl-32199911

ABSTRACT

BACKGROUND: Scavenger receptor CD163 is exclusively expressed on monocytes/macrophages and is widely used as a marker for alternatively activated macrophages. However, the role of CD163 is not yet clear. OBJECTIVES: We sought to examine the function of CD163 in steady-state as well as in sterile and infectious inflammation. METHODS: Expression of CD163 was analyzed under normal and inflammatory conditions in mice. Functional relevance of CD163 was investigated in models of inflammation in wild-type and CD163-/- mice. RESULTS: We describe a subpopulation of bone marrow-resident macrophages (BMRMs) characterized by a high expression of CD163 and functionally distinct from classical bone marrow-derived macrophages. Development of CD163+ BMRMs is strictly dependent on IFN regulatory factor-8. CD163+ BMRMs show a specific transcriptome and cytokine secretion pattern demonstrating a specific immunomodulatory profile of these cells. Accordingly, CD163-/- mice show a stronger inflammation in allergic contact dermatitis, indicating a regulatory role of CD163. However, CD163-/- mice are highly susceptible to S aureus infections, demonstrating the relevance of CD163 for antimicrobial defense as well. CONCLUSIONS: Our data indicate that anti-inflammatory and immunosuppressive mechanisms are not necessarily associated with a decreased antimicrobial activity. In contrast, our data define a novel macrophage population that controls overwhelming inflammation on one hand but is also necessary for an effective control of infections on the other hand.


Subject(s)
Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , Bone Marrow Cells/metabolism , Dermatitis, Allergic Contact/immunology , Inflammation/immunology , Macrophages/metabolism , Receptors, Cell Surface/metabolism , Staphylococcal Infections/immunology , Staphylococcus aureus/physiology , Animals , Antigens, CD/genetics , Antigens, Differentiation, Myelomonocytic/genetics , Bone Marrow Cells/immunology , Cells, Cultured , Cytokines/metabolism , Disease Models, Animal , Disease Susceptibility , Humans , Immunomodulation , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/metabolism , Macrophage Activation , Macrophages/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Receptors, Cell Surface/genetics , Transcriptome
19.
J Cardiovasc Transl Res ; 13(5): 744-757, 2020 10.
Article in English | MEDLINE | ID: mdl-32072564

ABSTRACT

The pathobiology of atherosclerosis and its current and potential future treatments are summarized, with a spotlight on three central cell types involved: (i) endothelial cells (ECs), (ii) macrophages, and (iii) vascular smooth muscle cells (VSMCs). (i) EC behaviour is regulated by the central transcription factors YAP/TAZ in reaction to biomechanical forces, such as hemodynamic shear stress. (ii) VSMC transdifferentiation (phenotype switching) to a macrophage-like phenotype contributes to the majority of cells positive for common cell surface macrophage markers in atherosclerotic plaques. (iii) Intra-plaque macrophages originate in a significant number from vascular resident macrophages. They can be activated via pattern recognition receptors on cell membrane (e.g. toll-like receptors) and inside cells (e.g. inflammasomes), requiring priming by neutrophil extracellular traps (NETs). ECs and macrophages can also be characterized by single-cell RNA sequencing. Adaptive immunity plays an important role in the inflammatory process. Future therapeutic options include vaccination, TRAF-STOPs, senolysis, or CD47 blockade. Graphical Abstract.


Subject(s)
Atherosclerosis/pathology , Endothelial Cells/pathology , Macrophages/pathology , Myocytes, Smooth Muscle/pathology , Adaptive Immunity , Animals , Atherosclerosis/immunology , Atherosclerosis/metabolism , Atherosclerosis/therapy , Cell Proliferation , Cell Transdifferentiation , Endothelial Cells/immunology , Endothelial Cells/metabolism , Humans , Macrophage Activation , Macrophages/immunology , Macrophages/metabolism , Mechanotransduction, Cellular , Myocytes, Smooth Muscle/immunology , Myocytes, Smooth Muscle/metabolism , Stress, Mechanical
20.
ACS Appl Bio Mater ; 3(10): 6919-6931, 2020 Oct 19.
Article in English | MEDLINE | ID: mdl-35019353

ABSTRACT

Nanomaterials allow designing targeted therapies, facilitate molecular diagnostics, and are therefore enabling platforms for personalized medicine. A systematic science and a predictive understanding of molecular/supramolecular structure relationships and nanoparticle structure/biological property relationships are needed for rational design and clinical progress but are hampered by the anecdotal nature, nonsystematic and nonrepresentative nanomaterial assortment, and oligo-disciplinary approach of many publications. Here, we find that a systematic and comprehensive multidisciplinary approach to production and exploration of molecular-structure/nanostructure relationship and nano-bio structure/function relationship of medical nanomaterials can be achieved by combining systematic chemical synthesis, thorough physicochemical analysis, computer modeling, and biological experiments, as shown in a nanomaterial family of amphiphilic, micelle-forming oxazoline/siloxane block copolymers suited for the clinical application. This comprehensive interdisciplinary approach leads to improved understanding of nanomaterial structures, allows good insights into binding modes for the nanomaterial protein corona, induces the design of minimal cell-binding materials, and yields rational strategies to avoid toxicity. Thus, this work contributes to a systematic and scientific basis for rational design of medical nanomaterials.

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