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1.
Neurosurgery ; 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38864626

ABSTRACT

BACKGROUND AND OBJECTIVES: Endovascular treatment of cerebral aneurysms has tremendously advanced over the past decades. Nevertheless, aneurysm residual and recurrence remain challenges after embolization. The objective of this study was to elucidate the portion of embolized aneurysms requiring open surgery and evaluate whether newer endovascular treatments have changed the need for open surgery after failed embolization. METHODS: All 15 cerebrovascular centers in Austria and the Czech Republic provided overall aneurysm treatment frequency data and retrospectively reviewed consecutive cerebral aneurysms treated with open surgical treatment after failure of embolization from 2000 to 2022. All endovascular modalities were included. RESULTS: On average, 1362 aneurysms were treated annually in the 2 countries. The incidence increased from 0.006% in 2005 to 0.008% in 2020 in the overall population. Open surgery after failed endovascular intervention was necessary in 128 aneurysms (0.8%), a proportion that remained constant over time. Subarachnoid hemorrhage was the initial presentation in 70.3% of aneurysms. The most common location was the anterior communicating artery region (40.6%), followed by the middle cerebral artery (25.0%). The median diameter was 6 mm (2-32). Initial endovascular treatment included coiling (107 aneurysms), balloon-assist (10), stent-assist (4), intrasaccular device (3), flow diversion (2), and others (2). Complete occlusion after initial embolization was recorded in 40.6%. Seventy-one percent of aneurysms were operated within 3 years after embolization. In 7%, the indication for surgery was (re-)rupture and, in 88.3%, reperfusion. Device removal was performed in 16.4%. Symptomatic intraoperative and postoperative complications occurred in 10.2%. Complete aneurysm occlusion after open surgery was achieved in 94%. CONCLUSION: Open surgery remains a rare indication for cerebral aneurysms after failed endovascular embolization even in the age of novel endovascular technology, such as flow diverters and intrasaccular devices. Regardless, it is mostly performed for ruptured aneurysms initially treated with primary coiling that are in the anterior circulation.

2.
Front Bioeng Biotechnol ; 8: 575379, 2020.
Article in English | MEDLINE | ID: mdl-33015025

ABSTRACT

This study reports on the use of pulsed electric field (PEF) as a pre-treatment step to enhance lipid extraction yield using extraction with ethanol-hexane blend on fresh oleaginous yeast Saitozyma podzolica. The yeasts were cultivated on nitrogen-depleted condition and had a lipid content of 26.4 ± 4.6% of dry weight. PEF-treatment was applied on the yeast suspension either directly after harvesting (unwashed route) or after a washing step (washed route) which induced a reduction of conductivity by a factor eight. In both cases, cell concentration was 20 g of biomass per liter of suspension. In the unwashed route, the lipid extraction efficiency increased from 7% (untreated) to 54% thanks to PEF-treatment. In case an additional washing step was added after PEF-treatment, up to 81% of the lipid content could be recovered. The washed route was even more efficient since lipid extraction yields increased from 26% (untreated) to 99% of total lipid. The energy input for the PEF-treatment never exceeded 150 kJ per liter of initial suspension. The best lipid recovery scenario was obtained using pulses of 1 µs, an electric field of 40 kV/cm and it required slightly less than 11 MJ/kgLIPID. This amount of energy can be further reduced by at least a factor five by optimizing the treatment and especially by increasing the concentration of the treated biomass. The process can be easily up-scaled and does not require any expensive handling of the biomass such as freezing or freeze-drying. These findings demonstrate the potential benefit of PEF-treatment in the downstream processing of oleaginous yeast. From a basic research point of view, the influence of conductivity on PEF energy requirements and extraction yields was examined, and results suggest a higher efficiency of PEF-treatment in terms of energy when treatment is performed at lower conductivity.

3.
Front Psychiatry ; 11: 460506, 2020.
Article in English | MEDLINE | ID: mdl-33101071

ABSTRACT

BACKGROUND: Substance use disorders (SUDs) have been described as a dysfunctional way to compensate for deficiencies in that person's underlying attachment system. Furthermore, the neuropeptide oxytocin (OT), which is a critical component of the neurobiology of the attachment system, has been shown to effectively reduce addictive behavior and therefore has been discussed as a potential medication in SUD treatment. This study investigates variation in peripheral OT plasma levels as a function of exposure to an attachment-related stimulus in SUD patients compared to healthy controls (HCs). METHODS: A total sample of 48 men, 24 inpatients in maintenance treatment who were diagnosed with poly-drug use disorder (PUD) and 24 HC, was investigated. A 15-min exposure to the Adult Attachment Projective Picture System (AAP) was used as an attachment-related stimulus and coded for attachment status. Blood samples before and after the AAP-assessment were taken and assayed for OT levels. Variation in baselines level of OT was examined in relation to the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), the Adult Attachment-Scale (AAS), and the Brief Symptom Inventory (BSI). RESULTS: Following the AAP stimulus controls showed no significant difference in OT levels elevation from baseline compared to the PUD group's OT levels. Furthermore, in the PUD group only OT-baseline-levels may be negatively associated with the AAS subscale "Comfort with Closeness" and "Anxiety" and lifetime substance use. DISCUSSION: Our results suggest that peripheral OT levels in poly-drug users undergoing maintenance treatment are not significantly different in responsiveness to an attachment related stimulus compared to HC. With regard to non-significant tendencies observed in this study which hint toward decreased OT-reactivity in the PUD group, further research is needed to explore this hypothesis with increased statistical power.

4.
Pathol Res Pract ; 215(7): 152380, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30871914

ABSTRACT

We describe an adult female patient diagnosed with spinal melanotic ependymoma. She underwent surgery with the aim of gross total resection, but only subtotal resection was possible. Therefore, the patient was re-evaluated 6 weeks following surgery. Radiotherapy was considered as further treatment. The diagnosis, clinical course, etiology and pathology are discussed on the basis of the current literature.


Subject(s)
Ependymoma/pathology , Spinal Neoplasms/pathology , Thoracic Vertebrae/pathology , Aged , Ependymoma/surgery , Female , Humans , Magnetic Resonance Imaging , Spinal Neoplasms/surgery , Thoracic Vertebrae/surgery
5.
Bioresour Technol ; 269: 179-187, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30172181

ABSTRACT

Pulsed Electric Field (PEF) pre-treatment, applied on fresh microalgae Auxenochlorella protothecoides, induces spontaneous release of a substantial water fraction and enables subsequent lipid extraction using ethanol-hexane blends. In this study, fresh microalgae suspensions were treated with PEF and incubated under inert conditions. Incubation promotes the release of ions and carbohydrates and increases the yields of subsequent lipid extraction thus enabling a considerable reduction of PEF-treatment energy. With a 20 h incubation period at 25 °C, almost total lipid extraction is achieved with a specific PEF-treatment energy of only 0.25 MJ/kgDW. Incubation on ice remains beneficial but less efficient than at 25 °C. Additionally, incubating microalgae cells in suspension at 100gDW/L or in a dense paste, was almost equally efficient. Correlation between the different results suggests that spontaneous release of ions and carbohydrates facilitates more successful lipid extraction. A direct causality between the two phenomena remains to be demonstrated.


Subject(s)
Electricity , Lipids/isolation & purification , Microalgae , Carbohydrates , Chlorophyta
6.
Biomed Res Int ; 2014: 301631, 2014.
Article in English | MEDLINE | ID: mdl-24967348

ABSTRACT

Recent studies demonstrated pigmented cells both in the murine heart, in pulmonary veins, and in brain arteries. Moreover, a role for melanocytes in the downregulation of inflammatory processes was suggested. As there is increasing evidence that inflammation is contributing significantly to the pathogenesis of intracranial aneurysms, melanocyte-like cells may be relevant in preventing age-related impairment of vessels. As pigmentation of the heart reflects that of coat color, aspects of body pigmentation might be associated with the incidence of intracranial aneurysms. We performed a case-control study to evaluate associations between the pigmentation of hair and eyes and the formation of aneurysms. In addition to hair and eye color, constitutive and facultative skin pigmentation were assessed in a replication study as well as individual handedness which can be seen as a neurophysiological correlate of developmental pigmentation processes. Hair pigmentation was highly associated with intracranial aneurysms in both samples, whereas eye pigmentation was not. In the replication cohort, facultative but not constitutive skin pigmentation proved significant. The strongest association was observed for individual handedness. Results indicate a significant association of intracranial aneurysms with particular aspects of body pigmentation as well as handedness, and imply clinical usefulness for screening of aneurysms and possible interventions.


Subject(s)
Eye Color , Hair Color , Intracranial Aneurysm/pathology , Intracranial Aneurysm/physiopathology , Skin Pigmentation , Adult , Aged , Case-Control Studies , Female , Humans , Male , Middle Aged , Risk Factors
7.
J Neurosurg ; 119(4): 1009-14, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23930856

ABSTRACT

OBJECT: Reinforcement of intracranial aneurysms (IAs) by wrapping or coating is a well-established therapeutic approach to those IAs not amenable to any other definitive treatment, but has been associated with complications such as parent artery narrowing, granuloma formation, and ischemic stroke. The goal of this study was to systematically investigate cerebrovascular complications following this procedure. METHODS: The authors' hospital database was searched for all patients who underwent wrapping or coating of IAs with cotton gauze and human fibrin adhesives between October 2006 and October 2011. The follow-up records of these patients were extracted, including regular clinical visits and vascular imaging. RESULTS: Five hundred sixty-seven patients were treated for IAs over the 5-year period: 303 patients underwent endovascular strategies and 264 underwent craniotomies. Wrapping or coating of IAs was performed in 20 patients (3.5%). Parent artery narrowing occurred in 5 (25%) of the 20 patients and was associated with major ischemic strokes in 4 patients and severe headache in another. Ischemic strokes were associated with parent artery narrowing, which occurred early postoperatively in 2 patients or was a consequence of granuloma formation in 2 patients 1 and 2 months after the procedure, respectively. CONCLUSIONS: These data should add to the awareness of significant cerebrovascular complications following wrapping or coating of IAs with cotton gauze and human fibrin adhesives and indicate that major ischemic strokes need to be included in the risk/benefit considerations during decision making for such treatment strategies. Patients who receive IA wrapping should be monitored and followed up closely for arterial narrowing and granuloma formation.


Subject(s)
Bandages/adverse effects , Brain Ischemia/etiology , Fibrin Tissue Adhesive/adverse effects , Granuloma/etiology , Intracranial Aneurysm/surgery , Stroke/etiology , Adult , Aged , Brain Ischemia/diagnostic imaging , Cerebral Angiography , Craniotomy , Databases, Factual , Female , Granuloma/diagnostic imaging , Humans , Intracranial Aneurysm/diagnostic imaging , Male , Middle Aged , Neurosurgical Procedures/adverse effects , Stroke/diagnostic imaging
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