New experimental model of acute aqueductal blockage in cats: effects on cerebrospinal fluid pressure and the size of brain ventricles

It is generally assumed that cerebrospinal fluid (CSF) is secreted in the brain ventricles, and so after an acute blockage of the aqueduct of Sylvius an increase in the ventricular CSF pressure and dilation of isolated ventricles may be expected. We have tested this hypothesis in cats. After blocking the aqueduct, we measured the CSF pressure in both isolated ventricles and the cisterna magna, and performed radiographic monitoring of the cross-sectional area of the lateral ventricle. The complete aqueductal blockage was achieved by implanting a plastic cannula into the aqueduct of Sylvius through a small tunnel in the vermis of the cerebellum in the chloralose-anesthetized cats. After the reconstitution of the occipital bone, the CSF pressure was measured in the isolated ventricles via a plastic cannula implanted in the aqueduct of Sylvius and in the cisterna magna via a stainless steel cannula. During the following 2 h, the CSF pressures in the isolated ventricles and cisterna magna were identical to those in control conditions. We also monitored the ventricular cross-sectional area by means of radiography for 2 h after the aqueductal blockage and failed to observe any significant changes. When mock CSF was infused into isolated ventricles to imitate the CSF secretion, the gradient of pressure between the ventricle and cisterna magna developed, and disappeared as soon as the infusion was terminated. However, when mock CSF was infused into the cisterna magna at various rates, the resulting increased subarachnoid CSF pressure was accurately transmitted across the brain parenchyma into the CSF of isolated ventricles. The lack of the increase in the CSF pressure and ventricular dilation during 2 h of aqueductal blockage suggests that aqueductal obstruction by itself does not lead to development of hypertensive acute hydrocephalus in cats

The application of ultrasound in neuroendoscopic procedures: first results with the new tool »NECUP-2« [Upotreba ultrazvuka u neuroendoskopskim procedurama: prvi rezultati s novim uređajem »NECUP-2«]

In this paper, our experience with originally constructed Neurosurgical Endoscopic Contact Ultrasound Probe »NECUP-2« in neuroendoscopy is reported. Between June 1997 and June 2007, 132 neuroendoscopic procedures have been performed: 102 endoscopic thrid ventriculostomies (ETV), 15 arachnoid cysts and 5 intraventricular tumours operations. The »NECUP-2« was applied effectively in all cases in which blunt perforation was not possible: 38/102 ETV, 10/10 septostomies, 15/15 arachnoid cysts. In five cases of intraventricular tumours, neuroendoscopic procedure was combined with open microsurgery for tumour removal with preservation of vascular structures. There were no »NECUP-2« related complications. Of postoperative complications, we had liquorrhea (9 patients), and symptoms of meningitis (6 patients). In the follow-up period (6 months to 6 years), we had a patency rate of 80% (50/63 patients). All patients improved in clinical status. According to the first results, it seems that ultrasonic contact probe NECUP-2 presents a new device in neurosurgical armamentarium that can be used in various fields of neurosurgery. With minimal and controlled lesion that is produced at the tip of the probe, it can be used in highly demanding operations such as third ventriculostomy and tumour resection

The effects of lumboperitoneal and ventriculoperitoneal shunts on the cranial and spinal cerebrospinal fluid volume in a patient with idiopathic intracranial hypertension

Lumboperitoneal (LP) and ventriculoperitoneal (VP) shunts are a frequent treatment modality for idiopathic intracranial hypertension (IIH). Although these shunts have been used for a long time, it is still not clear how they change the total craniospinal CSF volume and what portions of cranial and spinal CSF are affected. This report for the first time presents the results of a volumetric analysis of the total cranial and spinal CSF space in a patient with IIH. We performed an automated segmentation of the cranial and a manual segmentation of the spinal CSF space first with an LP shunt installed and again after the LP shunt was replaced by a VP shunt. When the LP shunt was in place, the total CSF volume was smaller than when the VP shunt was in place (222.4 cm(3) vs 279.2 cm(3)). The difference was almost completely the result of the spinal CSF volume reduction (49.3 cm(3) and 104.9 cm(3) for LP and VP, respectively), while the cranial CSF volume was not considerably altered (173.2 cm(3) and 174.2 cm(3) for LP and VP, respectively). This report indicates that LP and VP shunts in IIH do not considerably change the cranial CSF volume, while the reduction of CSF volume after LP shunt placement affects almost exclusively the spinal part of the CSF system. Our results suggest that an analysis of both the cranial and the spinal part of the CSF space is necessary for therapeutic procedures planning and for an early recognition of numerous side effects that often arise after shunts placement in IIH patients

Benutzung der öffentlichen Räume während der COVID-19-Pandemie – Erforschung von Stellungnahmen und Routinen von Studenten der Universität in Zagreb

Promjene životnih stilova, sve veća izgrađenost urbanog prostora, nedostatak održive urbane mobilnosti, zagađenje i posljedice globalnih klimatskih promjena te brojni drugi faktori utječu na urbanu kvalitetu života. U navedenom kontekstu dostupnost i kvaliteta javnog prostora sve više utječe na objektivne i subjektivne aspekte kvalitete života i dobrobit svih dobnih skupina stanovnika gradova, što je posebno došlo do izražaja tijekom pandemije bolesti COVID-19. Cilj rada je istražiti svakodnevne prakse studenata Sveučilišta u Zagrebu tijekom pandemije COVID-19 i njihove stavove o dostupnosti i kvaliteti urbanih javnih prostora. U tu svrhu provedeno je anketno istraživanje na prigodnom uzorku studenata Sveučilišta u Zagrebu (N=164). S ciljem kontekstualizacije rezultata napravljen je uvid u javno dostupne podatke o gradu Zagrebu. Fokus istraživanja bio je na dvije prostorne razine kako bi se istražili stavovi i prakse u mjerilu gradskih četvrti u kojima studenti žive te na prostoru središta grada Zagreba koji je u istraživanom periodu doživio naglu i značajnu transformaciju uslijed posljedica potresa i pandemije COVID-19. Javno dostupni podaci o gradu Zagrebu ukazuju na premali broj javnih zelenih površina na razini grada i na razini gradske četvrti, dok rezultati anketnog istraživanja pokazuju povećanu potrebu studenata za njima. Istraživanjem je uočena promjena svakodnevnih praksi i češći boravak studenata na javnim prostorima te stavovi koji naglašavaju važnost javnih zelenih površina u svakodnevnom životu studenata Sveučilišta u Zagrebu tijekom pandemije, na obje istraživane prostorne razine.Changing lifestyles, increasing over-development of urban space, lack of sustainable mobility, pollution and climate change, and other factors affect the urban quality of life. In this context, accessibility and quality of public space increasingly affect the subjective and objective aspects of quality of life and well-being of the entire urban population, especially during COVID -19 pandemic. The aim of this article is to investigate the daily practices and attitudes of students towards accessibility and quality of public space in the city during the pandemic. An online survey was conducted with a convenient sample of students from the University of Zagreb (N=164), and insight into publicly available data was provided for contextualization. The focus of the survey was at both the neighborhood and city level, which allowed for the examination of student attitudes and practices in the center of Zagreb, which experienced abrupt and significant change after the recent earthquake and pandemic. Insight into publicly available data revealed a deficit of public green spaces at both city and neighborhood levels, while survey results indicated more frequent use of public spaces, particularly the importance of public green spaces at both city and neighborhood levels in the daily lives of the student population during the pandemic.Die Änderungen des Lebensstils, die immer stärker bebauten städtischen Räume, das Fehlen einer nachhaltigen urbanen Mobilität, die Verschmutzung und die Folgen der globalen Klimaänderung, sowie zahlreiche andere Faktoren beeinflussen die urbane Lebensqualität. Im genannten Kontext beeinflussen die Verfügbarkeit und die Qualität des öffentlichen Raums immer mehr die objektiven und subjektiven Aspekte der Lebensqualität und das Wohl aller Altersgruppen in den Städten, dies kam besonders während der COVID-19-Pandemie zum Ausdruck. Das Ziel dieser Arbeit ist, die täglichen Routinen der Studenten der Zagreber Universität während der COVID-19-Pandemie, sowie deren Stellungnahmen zur Verfügbarkeit und Qualität der öffentlichen urbanen Räume zu erforschen. Zu diesem Zweck wurde eine Umfrage am adäquaten Muster der Studenten der Zagreber Universität durchgeführt (N=164). Um die Forschungsergebnisse in einen Kontext zu setzen, wurde die Einsicht in die öffentlich zugänglichen Daten über die Stadt Zagreb genommen. Der Fokus der Forschung lag auf zwei räumlichen Ebenen, damit die Stellungnahmen und Routinen im Massstab der Stadtviertel erforscht werden können, in denen Studenten leben, sowie in der Stadtmitte von Zagreb, die in der Forschungsperiode eine jähe und schwerwiegende Transformation als Folge des Erdbebens und der COVID-19-Pandemie erlebte. Die öffentlich zugänglichen Daten über die Stadt Zagreb weisen auf eine zu kleine Anzahl von Grünflächen auf, sowohl auf der Ebene der Stadt, als auch auf der Ebene der Stadtviertel. Die Umfrageergebnisse weisen jedoch auf einen gestiegenen Bedarf der Studenten danach. Aus der Forschung ergibt sich die Veränderung von täglichen Routinen und die Tatsache, dass Studenten sich immer öfter in öffentlichen Räumen aufhalten und dass sie die Wichtigkeit von öffentlichen Grünflächen in ihrem alltäglichen Leben betonen, besonders in den Zeiten der Pandemie, dies zeigt sich auf beiden Ebenen der erforschten Räume

Experimental and FE Modeling Investigation of Spot Welded Thin Steel Sheets

The spot welded thin steel sheets specimens are experimentally and numerically examined in this paper. The two specimens are joined using Resistance Spot Welding (RSW) method. The spot-welded joints consist of three zones with different material properties. Change of material properties during the welding process is caused by mechanical and thermal loading. The mechanical properties of thin steel sheets are determined by several tension tests. The specimens are cut in three different directions regarding a rolling direction of the basic material plate. Shear resistance of the spot welded joints is experimentally examined on the universal testing machine by displacement-controlled tensile loading tests. The numerical analysis is performed by large-strain plasticity theory implemented into a Finite Element Method based software. Comparison of the Finite Element (FE) modeling and experimental results verifies the proposed stress integration algorithm and modeling technique as powerful tools for prediction of the spot-welded joint behavior

Imunosupresivno liječenje nakon transplantacije pluća

Lung transplantation has become a life-saving procedure for individuals with variety of end-stage respiratory diseases. Optimal immunosuppression remains the key to long-term graft survivival. The protocols for immunosuppressive therapy following lung transplantation can be divided into three general categories: induction, maintenance, and treatment of rejection. The goal of induction therapy is to provide intense immunosuppression in the early post-transplantation period, when the risk of allograft rejection is the highest. Induction agents primarily target T lymphocytes, which are considered the effector cells in cell-mediated rejection. Current maintenance therapy typically includes a calcineurin inhibitor, nucleotide blocking agent and corticosteroid. Pulse steroids are generally the first treatment of acute cellular rejection. Therapeutic modalities for treatment of refractory cellular rejection include switch from cyclosporine to tacrolimus, use of lymphocyte depleting agents, azithromycine, and extracorporeal photopheresis. Treatment options for humoral rejections include plasmapheresis and immunoglobulines in combination with rituximab.Transplantacija pluća je postupak koji spašava život bolesnicima s krajnjim stadijem različitih plućnih bolesti. Optimalna imunosupresija predstavlja ključ dugotrajnog preživljenja presadka. Protokoli imunosupresivnog liječenja nakon transplantacije pluća mogu se podijeliti u tri glavne grupe: indukcijska terapija, terapija održavanja i terapija liječenja reakcija odbacivanja. Cilj indukcijske terapije je osigurati intenzivnu imunosupresiju u ranom posttransplantacijskom periodu, kada je rizik odbacivanja alografta najveći. Indukcijski lijekovi su primarno usmjereni na T limfocite, koji se smatraju glavnim stanicama u stanično posredovanoj reakciji odbacivanja. Trenutno se terapija održavanja tipično sastoji od inhibitora kalcineurina, antimetabolita i kortikosteroida. Pulsne doze kortikosteroida su prvi izbor liječenja akutnog staničnog odbacivanja. Načini liječenja refraktornog staničnog odbacivanja uključuju zamjenu ciklosporina takrolimusom, primjenu monoklonalnih i poliklonalnih antilimfocitnih protutijela, azitromicina i ekstrakorporalne fotofereze. Mogućnosti liječenja humoralnog odbacivanja uključuju plazmaferezu i imunoglobuline u kombinaciji s rituksimabom

Angiotensin-converting Enzyme 2 (ACE2) as a potential diagnostic and prognostic biomarker for chronic inflammatory lung diseases

Chronic inflammatory lung diseases are characterized by uncontrolled immune response in the airways as their main pathophysiological manifestation. The lack of specific diagnostic and therapeutic biomarkers for many pulmonary diseases represents a major challenge for pulmonologists. The majority of the currently approved therapeutic approaches are focused on achieving disease remission, although there is no guarantee of complete recovery. It is known that angiotensin-converting enzyme 2 (ACE2), an important counter-regulatory component of the renin–angiotensin–aldosterone system (RAAS), is expressed in the airways. It has been shown that ACE2 plays a role in systemic regulation of the cardiovascular and renal systems, lungs and liver by acting on blood pressure, electrolyte balance control mechanisms and inflammation. Its protective role in the lungs has also been presented, but the exact pathophysiological mechanism of action is still elusive. The aim of this study is to review and discuss recent findings about ACE2, including its potential role in the pathophysiology of chronic inflammatory lung diseases:, i.e., chronic obstructive pulmonary disease, asthma, and pulmonary hypertension. Additionally, in the light of the coronavirus 2019 disease (COVID-19), we will discuss the role of ACE2 in the pathophysiology of this disease, mainly represented by different grades of pulmonary problems. We believe that these insights will open up new perspectives for the future use of ACE2 as a potential biomarker for early diagnosis and monitoring of chronic inflammatory lung diseases

Hydroxyapatite Ceramics in Multilevel Cervical Interbody Fusion – Is There a Role?

The aim of this study is to evaluate the efficacy of hydroxyapatite grafts in multilevel cervical interbody fusion during the one year follow-up. A total of 86 patients with degenerative cervical disc disease underwent all together 224 cervical interbody fusion procedures in which either Smith-Robinson or Cloward type hydroxyapatite grafts were used. The surgeries included radiculopathy in 38 cases, myelopathy in 20 cases and myeloradicuopathy in 28 patients. In 65 out of 86 patients, fusion was followed by an anterior instrumentation (plating). Postoperatively, patients were followed for a mean of 15.64 (range 11–23.3) months. All patients underwent radiography to evaluate fusion and the axis curvature. Excellent clinical results (86%), described as a complete or partial relief of symptoms with full return to preop activity, were obtained in patients with radiculopathy. There were 5 grafts mobilizations and one graft fracture. Two grafts extruded in non-instrumented patients and required repeated surgery. There were other three reoperations due to the hardware problems. One year fusion rate was obtained at 86% for two-level surgery, 80.1% for three-level surgery and 74% for four-level surgery. The mean (SD) hospital stay was 3.8 (0.7) days. A hydroxyapatite cheramic can be a very effective synthetic material for multilevel cervical interbody fusion. It is characterized by a high fusion rate and a small percentage of graft-related complications, especially when fusion procedure is followed by plating

Intracranial epidural haematoma following surgical removal of a giant lumbosacral schwannoma: a case report and literature review.

Postoperative intracranial epidural haematoma (EDH) is an extremely rare complication following spinal surgery, with only a handful of cases described in the literature. We report the case of a 16-year-old girl who underwent a successful subtotal resection of a giant lumbosacral schwannoma (L2-S2 level). Recovery from general anaesthesia was uneventful; however, her neurological status deteriorated rapidly within 24 h after surgery. A head computed tomography scan revealed a large right frontoparietal EDH with midline shift. An immediate frontotemporoparietal osteoplastic craniotomy and evacuation of the EDH were performed. At 1 year postoperatively, the patient regained full neurological recovery with no radiological signs of growth of the residual tumour

Germline variants of the genes involved in NF-kB activation are associated with the risk of COPD and lung cancer development

Chronic obstructive pulmonary disease (COPD) and lung cancer (LC) are closely related diseases associated with smoking history and dysregulated immune response. However, not all smokers develop the disease, indicating that genetic susceptibility could be important. Therefore, the aim of this study was to search for the potential overlapping genetic biomarkers, with a focus on single nucleotide polymorphisms (SNPs) located in the regulatory regions of immune-related genes. Additionally, the aim was to see if an identified SNP has potentially an effect on proinflammatory cytokine concentration in the serum of COPD patients. We extracted summary data of variants in 1511 immune-related genes from COPD and LC genome-wide association studies (GWAS) from the UK Biobank. The LC data had 203 cases, patients diagnosed with LC, and 360 938 controls, while COPD data had 1 897 cases and 359 297 controls. Assuming 1 association/gene, SNPs with a p-value < 3.3 × 10–5 were considered statistically significantly associated with the disease. We identified seven SNPs located in different genes (BAG6, BTNL2, TNF, HCP5, MICB, NCR3, ABCF1, TCF7L1) to be associated with the COPD risk and two with the LC risk (HLA-C, HLA-B), with statistical significance. We also identified two SNPs located in the IL2RA gene associated with LC (rs2386841; p = 1.86 × 10–4) and COPD (rs11256442; p = 9.79 × 10–3) but with lower significance. Functional studies conducted on COPD patients showed that RNA expression of IL2RA, IFNγ and related proinflammatory cytokines in blood serum did not correlate with a specific genotype. Although results presented in this study do not fully support our hypothesis, it is worth to mention that the identified genes/SNPs that were associated with either COPD or LC risk, all were involved in the activation of the NF-κB transcription factor which is closely related to the regulation of the inflammatory response, a condition associated with both pathologies