Studienprotokoll: Register zur Prognose akut-symptomatischer Anfälle (PROSA-Register) – eine prospektive multizentrische Beobachtungsstudie

Background: Acute symptomatic epileptic seizures occur in close temporal relation to an acute disturbance of brain function. They are associated with a low risk of subsequent unprovoked seizures; thus, current guidelines recommend not to administer a long-term antiseizure medication; however, in clinical practice long-term secondary seizure prophylaxis is frequently initiated. The seizure prognosis after guideline-conform untreated or only briefly treated acute symptomatic seizures, is so far unknown. Hypothesis: Following an acute symptomatic first epileptic seizure of structural etiology, the 1-year risk of subsequent unprovoked seizures is not higher than 25%, even if antiseizure medication was not applied or for a short period only. Methods: The PROSE register is a single-arm, open, prospective, multicenter observational study. A total of 115 subjects aged 18 years or older with an acute symptomatic first epileptic seizure of structural etiology will be included if the seizure was not a status epilepticus. Intrahospital follow-up will be based on the hospital records. Telephone follow-up interviews will be conducted 3, 6, and 12 months after the acute symptomatic seizure. Discussion: The PROSE register will shed light on current treatment practice of acute symptomatic seizures and the actual seizure outcome within 1 year. The results are assumed to support the current evidence that giving antiseizure medication for a longer period of time exceeding the acute phase of the underlying condition is unnecessary

Toward Luminescent Composites by Phase Transfer of SrF2:Eu3+ Nanoparticles Capped with Hydrophobic Antenna Ligands

Transparent dispersions of hydrophobic SrF2 : Eu3+ nanoparticles in cyclohexane with up to 20% europium were obtained by fluorolytic sol‐gel synthesis followed by phase transfer into cyclohexane through capping with sodium dodecylbenzenesulfonate (SDBS). The particles were characterized by TEM, XRD and DLS as spherical objects with a diameter between 6 and 11 nm in dry state. 1H‐13CP MAS NMR experiments revealed the binding of the anionic sulfonate head group to the particle surface. The particles show bright red luminescence upon excitation of the aromatic capping agents, acting as antennas for an energy transfer from the benzenesulfonate unit to the Eu3+ centers in the particles. This synthesis method overcomes the current obstacle of the fluorolytic sol‐gel synthesis that transparent dispersions can be obtained directly only in hydrophilic solvents. To demonstrate the potential of such hydrophobized alkaline‐earth fluoride particles, transparent luminescent organic‐inorganic composites with 10% SrF2 : Eu3+ embedded into polyTEGDMA, polyBMA, polyBDDMA and polyD3MA, respectively, were prepared, endowing the polymers with the luminescence features of the nanoparticles.Peer Reviewe

Anatomy of a viral entry platform differentially functionalized by integrins α3 and α6

During cell invasion, human papillomaviruses use large CD151 patches on the cell surface. Here, we studied whether these patches are defined architectures with features for virus binding and/or internalization. Super-resolution microscopy reveals that the patches are assemblies of closely associated nanoclusters of CD151, integrin α3 and integrin α6. Integrin α6 is required for virus attachment and integrin α3 for endocytosis. We propose that CD151 organizes viral entry platforms with different types of integrin clusters for different functionalities. Since numerous viruses use tetraspanin patches, we speculate that this building principle is a blueprint for cell-surface architectures utilized by viral particles

Tetraspanin CD151 mediates papillomavirus type 16 endocytosis

Human papillomavirus type 16 (HPV16) is the primary etiologic agent for cervical cancer. The infectious entry of HPV16 into cells occurs via a so-far poorly characterized clathrin- and caveolin-independent endocytic pathway, which involves tetraspanin proteins and actin. In this study, we investigated the specific role of the tetraspanin CD151 in the early steps of HPV16 infection. We show that surface-bound HPV16 moves together with CD151 within the plane of the membrane before they cointernalize into endosomes. Depletion of endogenous CD151 did not affect binding of viral particles to cells but resulted in reduction of HPV16 endocytosis. HPV16 uptake is dependent on the C-terminal cytoplasmic region of CD151 but does not require its tyrosine-based sorting motif. Reexpression of the wild-type CD151 but not mutants affecting integrin functions restored virus internalization in CD151-depleted cells. Accordingly, short interfering RNA (siRNA) gene knockdown experiments confirmed that CD151-associated integrins (i.e., α3β1 and α6β1/4) are involved in HPV16 infection. Furthermore, palmitoylation-deficient CD151 did not support HPV16 cell entry. These data show that complex formation of CD151 with laminin-binding integrins and integration of the complex into tetraspanin-enriched microdomains are critical for HPV16 endocytosis

More holes, more contrast? Comparing an 18-gauge non-fenestrated catheter with a 22-gauge fenestrated catheter for cardiac CT.

ObjectiveTo compare the performance of an 18-gauge nonfenestrated catheter (18-NFC) with a 22-gauge fenestrated catheter (22-FC) for cardiac CT angiography (CCTA) in patients with suspected coronary heart disease.Subjects and methods74 consecutive patients imaged on a 2nd generation dual-source CT with arterial phase CCTA were included in this retrospective investigation to either an 18-NFC or 22-FC. In comparison to the 18-NFC, the 22-FC has three additional perforations for contrast agent dispersal proximal to the tip. We examined the two groups for differences in their average attenuation in the right and left ventricles (RV, LV) and in the atrium (RA, LA) as well as in the proximal right coronary artery (RCA) and the left main coronary artery (LM). The averages were calculated for both the 18-NFC and 22-FC.ResultsCatheters were successfully placed on the first attempt 97% (36/37) for 18-NFC and 95% (35/37) for the 22-FC. The following enhancement levels were measured: 22-FC (in Hounsfield-Units (HU)): RV = 203±29, LV = 523±36, RA = 198±29, LA = 519±38, RCA = 547±26, LM = 562±25; 18-NFC: RV = 146±26, LV = 464±32, RA = 141±24, LA = 438±35, RCA = 501±23, LM = 523±23; RV (p = 0,03), LV (p = 0.12), RA (p = 0.02), LA (p = 0.04), RCA (p = 0.3), LM (p = 0.33).ConclusionNo significant differences in attenuation levels as well as in image quality of the coronary arteries were found between NFC and FC. Nevertheless, the 22-gauge FC examinations showed significantly higher attenuation in the left and right atrium as well as the right ventricle. Patients with poor venous access may benefit from a smaller gauge catheter that can deliver sufficiently high flow rates for CCTA

Spontaneous white matter damage, cognitive decline and neuroinflammation in middle-aged hypertensive rats : an animal model of early-stage cerebral small vessel disease

Introduction Cerebral small vessel disease (cSVD) is one of the most prevalent neurological disorders. The progressive remodeling of brain microvessels due to arterial hypertension or other vascular risk factors causes subtle, but constant cognitive decline through to manifest dementia and substantially increases the risk for stroke. Preliminary evidence suggests the contribution of the immune system to disease initiation and progression, but a more detailed understanding is impaired by the unavailability of appropriate animal models. Here, we introduce the spontaneously hypertensive rat (SHR) as a model for early onset cSVD and unveiled substantial immune changes in conjunction with brain abnormalities that resemble clinical findings. Results In contrast to age-matched normotensive Wistar Kyoto (WKY) rats, male SHR exhibited non-spatial memory deficits. Magnetic resonance imaging showed brain atrophy and a reduction of white matter volumes in SHR. Histological analyses confirmed white matter demyelination and unveiled a circumscribed blood brain barrier dysfunction in conjunction with micro- and macrogliosis in deep cortical regions. Flow cytometry and histological analyses further revealed substantial disparities in cerebral CD45high leukocyte counts and distribution patterns between SHR and WKY. SHR showed lower counts of T cells in the choroid plexus and meningeal spaces as well as decreased interleukin-10 levels in the cerebrospinal fluid. On the other hand, both T and NK cells were significantly augmented in the SHR brain microvasculature. Conclusions Our results indicate that SHR share behavioral and neuropathological characteristics with human cSVD patients and further undergird the relevance of immune responses for the initiation and progression of cSVD

Interactive Volumetry Of Liver Ablation Zones

Percutaneous radiofrequency ablation (RFA) is a minimally invasive technique that destroys cancer cells by heat. The heat results from focusing energy in the radiofrequency spectrum through a needle. Amongst others, this can enable the treatment of patients who are not eligible for an open surgery. However, the possibility of recurrent liver cancer due to incomplete ablation of the tumor makes post-interventional monitoring via regular follow-up scans mandatory. These scans have to be carefully inspected for any conspicuousness. Within this study, the RF ablation zones from twelve post-interventional CT acquisitions have been segmented semi-automatically to support the visual inspection. An interactive, graph-based contouring approach, which prefers spherically shaped regions, has been applied. For the quantitative and qualitative analysis of the algorithm’s results, manual slice-by-slice segmentations produced by clinical experts have been used as the gold standard (which have also been compared among each other). As evaluation metric for the statistical validation, the Dice Similarity Coefficient (DSC) has been calculated. The results show that the proposed tool provides lesion segmentation with sufficient accuracy much faster than manual segmentation. The visual feedback and interactivity make the proposed tool well suitable for the clinical workflow.Peer reviewe

Study protocol: register on the prognosis of acute symptomatic seizures (PROSA register)-A prospective multicenter observational study

Background Acute symptomatic epileptic seizures occur in close temporal relation to an acute disturbance of brain function. They are associated with a low risk of subsequent unprovoked seizures; thus, current guidelines recommend not to administer a long-term antiseizure medication; however, in clinical practice long-term secondary seizure prophylaxis is frequently initiated. The seizure prognosis after guideline-conform untreated or only briefly treated acute symptomatic seizures, is so far unknown. Hypothesis Following an acute symptomatic first epileptic seizure of structural etiology, the 1-year risk of subsequent unprovoked seizures is not higher than 25%, even if antiseizure medication was not applied or for a short period only. Methods The PROSE register is a single-arm, open, prospective, multicenter observational study. A total of 115 subjects aged 18 years or older with an acute symptomatic first epileptic seizure of structural etiology will be included if the seizure was not a status epilepticus. Intrahospital follow-up will be based on the hospital records. Telephone follow-up interviews will be conducted 3, 6, and 12 months after the acute symptomatic seizure. Discussion The PROSE register will shed light on current treatment practice of acute symptomatic seizures and the actual seizure outcome within 1 year. The results are assumed to support the current evidence that giving antiseizure medication for a longer period of time exceeding the acute phase of the underlying condition is unnecessary

Prognosis and management of acute symptomatic seizures: a prospective, multicenter, observational study

Abstract Background Acute symptomatic epileptic seizures are frequently seen in neurocritical care. To prevent subsequent unprovoked seizures, long-term treatments with antiseizure medications are often initiated although supporting evidence is lacking. This study aimed at prospectively assessing the risk of unprovoked seizure relapse with respect to the use of antiseizure medications. It was hypothesized that after a first acute symptomatic seizure of structural etiology, the cumulative 12-month risk of unprovoked seizure relapse is ≤ 25%. Methods Inclusion criteria were age ≥ 18 and acute symptomatic first-ever epileptic seizure; patients with status epilepticus were excluded. Using telephone and mail interviews, participants were followed for 12 months after the acute symptomatic first seizure. Primary endpoint was the occurrence and timing of a first unprovoked seizure relapse. In addition, neuro-intensivists in Germany were interviewed about their antiseizure treatment strategies through an anonymous online survey. Results Eleven of 122 participants with structural etiology had an unprovoked seizure relapse, resulting in a cumulative 12-month risk of 10.7% (95%CI, 4.7%–16.7%). None of 19 participants with a non-structural etiology had a subsequent unprovoked seizure. Compared to structural etiology alone, combined infectious and structural etiology was independently associated with unprovoked seizure relapse (OR 11.1; 95%CI, 1.8–69.7). Median duration of antiseizure treatment was 3.4 months (IQR 0–9.3). Seven out of 11 participants had their unprovoked seizure relapse while taking antiseizure medication; longer treatment durations were not associated with decreased risk of unprovoked seizure relapse. Following the non-representative online survey, most neuro-intensivists consider 3 months or less of antiseizure medication to be adequate. Conclusions Even in case of structural etiology, acute symptomatic seizures bear a low risk of subsequent unprovoked seizures. There is still no evidence favoring long-term treatments with antiseizure medications. Hence, individual constellations with an increased risk of unprovoked seizure relapse should be identified, such as central nervous system infections causing structural brain damage. However, in the absence of high-risk features, antiseizure medications should be discontinued early to avoid overtreatment