The amounts of the following proteins were increased in stable atherosclerotic plaques at the stage of lipidosis and fibrosis: vimentin, tropomyosin β-chain, actin, keratin, tubulin β-chain, microfibril-associated glycoprotein 4, serum amyloid P-component, and annexin 5. In plaques at the stage of fibrosis and calcification, the amounts of mimecan and fibrinogen were increased. In unstable atherosclerotic plaque of the necrotic–dystrophic type, the amounts of human serum albumin, mimecan, fibrinogen, serum amyloid P-component and annexin were increased. Conclusion: This proteomic study identifies the proteins present in atherosclerotic plaques of coronary arteries by comparing their proteomes at three different stages of plaque development during coronary atherosclerosis.Background: To study the changes in protein composition of atherosclerotic plaques at different stages of their development in coronary atherosclerosis using proteomics. Methods: The object of research consisted of homogenates of atherosclerotic plaques from coronary arteries at different stages of development, obtained from 15 patients. Plaque proteins were separated by two-dimensional electrophoresis. The resultant protein spots were identified by the matrix-assisted laser desorption ionization method with peptide mass mapping. Results: Groups of differentially expressed proteins, in which the amounts of proteins differed more than twofold ( Proteomic studies have contributed substantially to the research on the pathogenesis of cardiovascular diseases, thus laying the foundation for the discovery of novel molecular targets and novel biomarkers of the risk of cardiovascular diseases and their complications ,2. Mass-Studies in the field of coronary atherosclerosis etiology and pathogenesis, which predetermine coronary atherosclerosis complications, are currently relevant because of the high prevalence and mortality rate of this disease. Several proteomic studies on human atherosclerotic plaques have been conducted to date. By mass-spectrometric analysis, Herrington et al. have investigated the human arterial proteome and proteomic features. They uncovered substantial differences in the prevalence of a mitochondrial protein, tumor necrosis factor α, insulin receptor, and PPAR-α and -γ between coronary and aortic samples and between atherosclerotic and healthy tissues . The stuTo study the involvement of proteins in the pathological process of coronary atherosclerosis, it is important to investigate the specific relations between proteins characteristic of different developmental stages of atherosclerotic lesions in coronary arteries. In addition to known lipid and inflammatory molecules, some proteins can affect the development of atherosclerotic lesions into unstable plaques. A time-course study of the proteomic profile of the vascular wall during coronary atherosclerosis may help to discover possible diagnostically significant protein patterns or potential biomarkers of the disease and to develop new approaches for the diagnosis of coronary atherosclerosis and its complications.The aim of this study was to investigate via proteomic technologies changes in the proteomic profile of atherosclerotic plaques at different stages of development in coronary arteries during coronary atherosclerosis.The study protocol was approved by the local Ethics Committee of the Institute of Internal and Preventive Medicine . Written informed consent to be examined and to participate in the study was obtained from each patient. All the authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship for this manuscript, take responsibility for the integrity of the work as a whole, and have given final approval to the version to be published.The object of research consisted of the samples of atherosclerotic plaque tissues containing the intima–media layer of coronary arteries. All the samples were collected from patients with well-pronounced coronary atherosclerosis, who underwent coronary bypass surgery, during which it was deemed necessary to perform endarterectomy from coronary arteries. All the participants signed informed-consent forms regarding their enrollment in the study.To minimize differences in clinical characteristics among the groups, the samples were collected from 15 patients with similar clinical characteristics: men, age 62.89 ± 6.97 (49/71) years (M ± SD (min/max)), body-mass index 28.5 ± 4.1 (21.11/33.74), diagnosis: angina pectoris III FC; two people in each group had myocardial infarction in the past, none of the patients had a history diabetes type 2, and all were non-smokers. Exclusion criteria were as follows: myocardial infarction less than 6 months before the study, acute chronic infectious and inflammatory diseases or their deterioration, renal failure, active liver disease, cancer, and hyperparathyroidism. The same amount of material (five plaques from five patients) was collected in each group.After morphological and histological analyses, all samples were categorized as stable or unstable atherosclerotic plaques, according to the criteria of Waksman and Seruys (2004) and Shah (2005) ,9. For tg, and the protein concentration was measured by the QuickStart™ Bradford protein assay .Pieces of tissue were ground in liquid nitrogen and lysed in electrophoresis buffer, incubated for 20 min at room temperature, then disrupted with an ultrasonicator  for 30 s on ice. The suspension was centrifuged for 30 min at 10 °С and 16,100× The proteins from atherosclerotic plaques were separated by two-dimensional electrophoresis. For this procedure, sample pools were prepared that corresponded to three stages of atherosclerotic plaque development. To this end, equal amounts of proteins (100 μg) from five samples at each stage were mixed. Next, 100 μg of proteins of each pool was loaded on strips 17 cm-long, pH range 4–7 . Five technical replicates were analyzed for each pool. The strips were rehydrated in electrophoresis buffer, 300 μL of each sample was loaded on the strips, and separation lasted for 12 at 50 mA per strip at 20 °С. Before separation in the second direction, the strips were stored at −80 °С and then equilibrated in a buffer supplemented with 130 mM dithiothreitol for 15 min and then in the above buffer supplemented with 200 mM iodoacetamide for additional 15 min. The strips were placed on a 12% polyacrylamide gel. The transfer of proteins into the gel was performed at 16 mA current, with subsequent separation of proteins at 25 mA per gel.The gels were stained with a fluorescent dye, SyproRuby  in a DodecaGelStainer camera (Bio-Rad) according to the manufacturer’s instructions. The stained gels were visualized by means of the VersaDoc MP4000 imaging system (Bio-Rad). Gel images were analyzed by the PDQuest software, version 8.1.0 (Bio-Rad). The gel with the greatest amount and the best resolution of protein spots was chosen as a master gel, relative to which all the protein spots were compared and matched among gels. To identify the differences between the stages, a comparison of the amount of proteins in each spot, expressed in relative units of intensity, was carried out. Correct matching of specific protein spots between gels was verified visually, with corrections if necessary.The spots were cut out of the gels using an EXQuestSpotCutter (Bio-Rad), and the gel pieces were washed with distilled water and incubated in a 50 mM solution of ammonium bicarbonate in 50% acetonitrile for 20 min at room temperature. After that, the gels were dried in acetonitrile, and the proteins were digested in-gel with trypsin via rehydration of the gel with a solution of modified porcine trypsin  at 15 μg/mL in50 mM ammonium bicarbonate. The hydrolysis lasted for 12 h at 37 °С.Isolation and purification of tryptic peptides was carried out using Millipore ZIP TIP C18 . Purified peptides were mixed with a saturated matrix solution, α-cyano-4-hydroxy-cinnamic acid  in 70% acetonitrile  with 0.1% trifluoroacetic acid . An aliquot (1 µl) of the resulting mixture was applied to a metal target of the mass spectrometer and air-dried. The measurements were carried out on an Ultraflex III instrument  using the following parameters: accelerating voltage: 25 kV, voltage reflectron: 26.3 kV; mass range 500–3500 Da, and delayed extraction 200 ns. Instrument calibration was performed using a standard type of hydrolysate of bovine serum albumin  at the following masses (Da): 937.48, 1163.63, 1283.71, 1305.71, 1399.69, 1439.81, 1479.79, 1567.74, 1639.93, 1724.84, 1880.92, 1907.92, 2045.02.http://matrixscience.com/home.html (6 October 2019). The search parameters were as follows: mass error ±0.05 Da, missing cleavages: one, modifications: oxidation of methionine and carbamidomethylation of cysteines, and database: SwissProt.Proteins were identified via their tryptic mass map by the search algorithm Mascot  were analyzed, and statistical significance was assumed at n = 55) that were differentially expressed by more than twofold (p < 0.05) between pools of homogenates from the three stages of atherosclerotic plaque development. Thirty spots were identified; the results of mass-spectrometric identification are given in During the comparison of the gels, the most abundant protein spots were selected for identification by MALDI mass spectrometry. The proteomic analysis uncovered groups of proteins , tubulin β chain. A mix of different isoforms of actin  was identified in some spots. A mix of tubulin β chain isoforms was found in spot 7. Increased amounts were noted for the cytoskeletal proteins vimentin, tropomyosin β chain, aortic smooth muscle actin, α cardiac muscle actin 1, tubulin β chain, MAGP-4, and keratin in the sample of stable atherosclerotic plaques at the stage of lipidosis and fibrosis. In addition, the maximum amounts of serum amyloid P-component (SAP) and annexin A were identified at the stage of lipidosis and fibrosis. The amounts of SAP and annexin 5 were significantly reduced in the sample at the stage of fibrosis and calcification, but at the stage of unstable plaques, the amounts of these proteins increased again.The relative amount of proteins in each spot was determined by the PDQuest program in relative units of intensity. Increased amounts were identified for fibrinogen β chain and mimecan in the sample of stable atherosclerotic plaques at the stage of fibrosis and calcification. Increased amounts were noted for serum albumin, mimecan, fibrinogen, SAP, and annexin 5 in plaques of the necrotic–dystrophic type at the stage of unstable atherosclerotic plaques.Thus, stable plaques at the stage of lipidosis and fibrosis are characterized by increased amounts of vimentin, tropomyosin β chain, actin, tubulin β chain, MAGP-4, keratin, SAP, and annexin A. Stable plaques at the stage of fibrosis and calcification are characterized by increased amounts of fibrinogen β chain and mimecan and decreased amounts of SAP and annexin A. Unstable atherosclerotic plaques are characterized by increased amounts of serum albumin, mimecan, fibrinogen, SAP, and annexin 5.Actin is a contractile catalytically inactive protein, existing in the forms of globular (monomeric) G-actin (43 kDa) and double-helical filaments called F-actin. Actin is functionally associated with tropomyosin and troponins. Tropomyosin (TM) is a regulatory fibrillar protein (70 kDa) consisting of two intertwined α-helices, which forms one complex with F-actin and ensures its stability. The stoichiometry of the TM–F-actin complexes corresponds to a molar ratio of 1. TM participates in the calcium-dependent regulation of muscle contraction . MutatioThe cytoskeleton proteins include tubulin, an important component of microtubules. Microtubules are involved in the implementation of the functions of endothelial cells, such as maintenance of cell shape, mitosis, intracellular transport, adhesion, and migration. Posttranslational modifications of tubulin, such as deacetylation, phosphorylation, and polyglutamation, are involved in the regulation of microtubule dynamics . OxidatiOur study demonstrated a significant increase in tubulin and MAGP-4 content in the sample of atherosclerotic plaques at the stage of lipidosis and fibrosis compared with the sample of stable plaques at the stage of fibrosis and calcification and with the sample of unstable plaques.The family of microfibril-associated glycoproteins (MAGP) consists of proteins of the extracellular matrix that affect the functionality of the cell. Gene mutations of these proteins are associated with aortic aneurysm, and increased expression of MAGP-2 has been proposed as an independent prognostic biomarker in ovarian cancer . MAGP-4 Vimentin (55 kDa) is an intermediate filament protein and a specific marker of changes in the molecular phenotype of epithelial cells; in fact, it is expressed de novo during phenotype change toward a mesenchymal phenotype. The dynamic nature of vimentin is important for alterations of cell shape, and this protein ensures structural integrity of the cell and its resistance to mechanical stress. It has been shown that cells devoid of vimentin are extremely sensitive to mechanical damage ,18. AfteIn our study, it was demonstrated that stable atherosclerotic plaques at the stage of lipidosis and fibrosis were characterized by increased amounts of cytoskeletal proteins such as actin, tropomyosin, tubulin, MAGP-4, and vimentin; this alteration is apparently associated with cellular migration to the subendothelial space after damage to the vessel wall (during subsequent inflammation). Meanwhile, stable atherosclerotic plaques at the stage of lipidosis and fibrosis contained greater amounts of these proteins. Evidently, this phenomenon may be explained by the fact that a stable atherosclerotic plaque at the stage of lipidosis and fibrosis is more common at the earlier stages of the atherosclerotic process.Type I keratins are cytokeratins (40–70 kDa) that constitute intermediate filaments of the cytoskeleton and are present in all epithelial cells of mammals. The expression of cytokeratins located in smooth muscle cells is significantly higher in carotid arteries with atherosclerosis in comparison with healthy carotid arteries . CytokerOur study indicates that the amount of keratin was significantly increased in the samples of stable atherosclerotic plaques at the stage of lipidosis and fibrosis, as compared with unstable atherosclerotic plaques. This finding does not contradict the above-mentioned properties of cytokeratin in relation to aberrations in endothelium function and oxidative changes that are typical for earlier stages of atherosclerotic lesion development, that in our study, we suggested for stable atherosclerotic plaques.Our results are consistent with those of Tu et al., who have reported substantial upregulation of the proteins tropomyosin, actin, and keratinin in the carotid artery and middle cerebral artery in rabbits with hyperlipidemia and with insignificant atherosclerotic changes .Fibrinogen is a known acute-phase protein, a glycoprotein involved in the final stage of coagulation. Fibrinogen was present in the samples of atherosclerotic plaques at all stages of development, but the amount of this protein increased significantly (more than two fold) in stable atherosclerotic plaques at the stage of fibrosis and calcification and in a sample of unstable plaques compared to the sample of plaques at the stage of lipidosis and fibrosis.In addition, we found the maximum amount of SAP and annexin A5 in the sample of atherosclerotic plaques at the stage of lipidosis and fibrosis. In this case, the contents of these proteins were significantly reduced at the stage of fibrosis and calcification but increased again at the stage of unstable plaques.SAP is an acute-phase protein, a member of the pentraxin family of serum proteins. SAP plays a significant role in the biological processes of the cardiovascular system, such as inflammation and fibrosis. The amount of SAP in tissues increases in degenerative aortic stenosis; in addition, SAP levels in plasma are positively associated with cardiovascular diseases in the elderly . In a stAnnexin 5 belongs to a group of annexin proteins with structural similarity and functional ability to bind phospholipids in the presence of calcium ions. Annexin 5 is found in the vascular endothelium and has anti-inflammatory, anticoagulant, and anti-apoptotic effects by binding phosphatidylserine molecules . In the At present, our data do not allow us to answer the question of why the amount of these proteins decreased in stable atherosclerotic plaques at the stage of fibrosis and calcification but was restored in unstable plaques. In addition, the sample of atherosclerotic plaques at the fibrosis and calcification stage was characterized by a high content of mimecan relative to the plaques at the lipidosis and fibrosis stage and relative to the sample of unstable plaques.Mimecan (or osteoglycin) is a major component of the extracellular matrix. Mimecan is involved in the pathogenesis of atherosclerosis by regulating proliferation, apoptosis, and migration of vascular smooth muscle cells . ProteomHuman serum albumin (HSA) is the main protein of human plasma. HSA is synthesized in the liver, serves as an amino acid reserve for protein synthesis, and performs a transport function in the blood. HSA has antioxidant activity because of its ability to bind reactive oxygen species . HSA andDirajlal-Fargo and coworkers have demonstrated that a low concentration of HSA in the blood is a predictor of atherosclerosis in blood vessels regardless of the traditional risk factors and statin therapy in patients with HIV infection. Furthermore, it has been shown that HSA is associated with markers of systemic inflammation and hypercoagulation . The pathophysiological mechanism underlying this association—according to thwse authors—is the ability of HSA to bind many ligands, including proatherogenic ones, thereby preventing their contribution to oxidative stress . In the The mechanism triggering the development of myocardial infarction involves a tear or crack in the thin cover of an (predominantly) unstable atherosclerotic plaque; therefore, the results of our study do not contradict the above-mentioned data. We detected increased amount of HSA in the sample of unstable atherosclerotic plaques of the necrotic–dystrophic type. An unstable atherosclerotic plaque is characterized by overexpression of various proatherogenic factors and ligands, thus possibly drawing HSA from the blood plasma to the atherosclerotic lesions.In a proteomic experiment, we demonstrated that early phases of coronary atherosclerosis at the stage of stable atherosclerotic plaques (lipidosis and fibrosis) show increased amounts of cytoskeletal proteins , SAP, and annexin 5.The progression of the atherosclerotic process from stable atherosclerotic plaques to the stage of fibrosis and calcification leads to a decrease in the concentration of these proteins and to a significant increase in the levels of mimecan and fibrinogen.At the stage of an unstable atherosclerotic plaques of the necrotic–dystrophic type, an increased amount of HSA is observed. It is possible that the high concentration of HSA in an atherosclerotic plaque correlates with the instability of the atherosclerotic plaque. In addition, unstable plaques are characterized by the preservation of a high content of mimecan and fibrinogen and the re-establishment of the previous high level of SAP and annexin 5.This proteomic study identifies the proteins of atherosclerotic plaques in coronary arteries by comparing plaque proteomes at three different stages of plaque development during coronary atherosclerosis. These results require validation in further studies with large groups to confirm the prognostic value of these biomarkers and their association with instable human coronary artery plaques.


N-oxide (TMAO), a small molecule produced by the metaorganismal metabolism of dietary choline, has been implicated in human disease pathogenesis, including known risk factors for Alzheimer’s disease (AD), such as metabolic, cardiovascular, and cerebrovascular disease.Trimethylamine n = 410) of individuals with Alzheimer’s clinical syndrome (n = 40), individuals with mild cognitive impairment (MCI) (n = 35), and cognitively-unimpaired individuals (n = 335). Linear regression analyses were used to determine differences in CSF TMAO between groups , as well as to determine relationships between CSF TMAO and CSF biomarkers of AD (phosphorylated tau and beta-amyloid) and neuronal degeneration .In this study, we tested whether TMAO is linked to AD by examining TMAO levels in cerebrospinal fluid (CSF) collected from a large sample (42) and neuronal degeneration .CSF TMAO is higher in individuals with MCI and AD dementia compared to cognitively-unimpaired individuals, and elevated CSF TMAO is associated with biomarkers of AD pathology  contains supplementary material, which is available to authorized users. N-oxide (TMAO) has been implicated in metabolic [l-carnitine [The human gut is home to trillions of microbes, including bacteria, eukaryotes, and viruses, that participate in a lifelong symbiotic relationship with their human hosts. Resident gut microbes perform essential functions for human health ranging from regulating nutrition and metabolism to influencing immune system development and function . Gut micetabolic , cardiovetabolic , 7, and etabolic  disease.arnitine . TMA thearnitine . A recenarnitine  demonstrarnitine .Alzheimer’s disease (AD) pathology is characterized by extracellular beta-amyloid (Aβ) plaques and intracellular neurofibrillary tangles composed of hyperphosphorylated tau protein . The undn = 277) and the Wisconsin Registry for Alzheimer’s Prevention (WRAP) study (n = 137) who had undergone lumbar puncture with CSF collection, as well as TMAO and biomarker quantification. The ADRC clinical core study consists of participants who fall along the clinical continuum of cognitive function, including AD dementia, MCI, and cognitively-unimpaired controls. The WRAP study is a large (> 1500 subjects), ongoing (> 15 years), prospective longitudinal investigation of the genetic, biological, and lifestyle factors that contribute to the development of AD dementia and cognitive decline [APOE ε4 genotype is more prevalent. General exclusion criteria for the ADRC and WRAP studies include any significant neurologic disease (other than AD dementia), history of alcohol/substance dependence, major psychiatric disorders (including untreated major depression), or other significant medical illness. APOE ε4 genotyping procedures have been described previously [APOE ε4 carriers . The University of Wisconsin Health Science Institutional Review Board approved all study procedures, and all experiments were performed in accordance with relevant guidelines and regulations. All participants provided written informed consent to be involved in this study.We identified 414 individuals in the Wisconsin Alzheimer’s Disease Research Center (ADRC) clinical core , n = 35 MCI (MCI group), and n = 40 AD dementia (AD group).Participants underwent a comprehensive neuropsychological battery to determine their cognitive status. Participants with MCI and AD dementia were diagnosed using available clinical and cognitive information in accordance with the updated 2011 National Institute on Aging–Alzheimer’s Association workgroup diagnostic criteria . All parg for 10 min. Supernatants were frozen in 0.5 ml aliquots in polypropylene tubes and stored at − 80 °C.Lumbar puncture and CSF collection procedures have been described previously . Briefly42/Aβ40 ratio, phosphorylated tau (p-tau), and the p-tau/Aβ42 ratio. CSF Aβ is an indicator of amyloid burden, with greater amyloid deposition in the brain being reflected by lower levels in the CSF. The Aβ42/Aβ40 ratio  was used given that it shows better correspondence with brain amyloid deposition as well as superior diagnostic performance compared to CSF Aβ42 alone [42 incorporates both facets of pathology, with higher values indicating greater AD pathology [42/Aβ40 ratio, CSF Aβ42 and CSF Aβ40 were quantified separately by electrochemiluminescence (ECL) using an Aβ triplex assay . For p-tau and the p-tau/Aβ42 ratio, CSF p-tau and Aβ42 were quantified using commercially available sandwich ELISAs .CSF AD biomarkers included the Aβ42 alone . p-tau iathology . For then = 192 samples in batch 1, n = 218 samples in batch 2), and all statistical analyses accounted for batch variation .CSF biomarkers of neuronal degeneration included total tau (t-tau), neurofilament light chain protein , and neurogranin (a marker of synaptic degeneration). CSF t-tau and NFL were quantified using commercially available sandwich ELISAs: t-tau, INNOTEST hTau Ag (Fujirebio Europe); and NFL, NF-Light ELISA kit . CSF neurogranin was quantified using a sandwich ELISA as described previously . All CSFm/z) area-under-the-curve values for TMAO and scaled to a median value of 1.CSF TMAO was quantified via an untargeted plasma metabolomics analysis performed by Metabolon, Inc.  using ultrahigh performance liquid chromatography tandem mass spectrometry (UHPLC-MS) as described previously  details: MethodsAPOE ε4 genotype, and clinical diagnosis  on CSF TMAO levels. CSF TMAO was natural log transformed to account for a nonnormal distribution. Secondarily, linear regression models were used to determine the relationship between CSF TMAO and CSF biomarkers . Separate models were run for each CSF biomarker, and each model included covariates of age, sex, and the nuisance covariate of CSF analysis batch (to account for batch variation). Given that TMAO has been implicated in cardiovascular disease, and that vascular disease risk factors are associated with AD and neurodegeneration, the same linear regression models were run for each CSF biomarker with the addition of peripheral vascular disease measures as covariates . Nonnormally distributed variables were natural log transformed.Our analysis approach first examined differences in CSF TMAO levels between clinical diagnostic groups, and then extended these analyses in order to characterize the biological relationships between CSF TMAO and biomarkers of both AD pathology and neurodegeneration. To determine CSF TMAO differences between groups, a multiple linear regression model was conducted in R (v3.5.0) to test the effect of age, sex, APOE ε4 genotype was more prevalent in the MCI and AD dementia groups. There were no differences between groups with respect to cardiovascular disease risk factors including BMI, blood pressure, total cholesterol, HDL cholesterol, and fasting glucose.Participant characteristics are reported in Table β = 0.50, p < 0.0001) and MCI  compared to cognitively-unimpaired individuals , but there were no main effects of sex or APOE ε4 genotype, and CSF TMAO levels did not differ between the MCI and AD groups.CSF TMAO levels were elevated in individuals with AD dementia  and biomarkers of neuronal degeneration (D–F). Table S1. Summary of multiple linear regressions testing relationships between CSF TMAO and CSF biomarkers of AD pathology and neurodegeneration. (PDF 895 kb)


In this exploratory study, we found higher levels of the inflammatory biomarker SAA in PDD and MSA compared with controls and PD and higher levels of CRP in PDD and MSA compared with PD. YKL-40 was lower in PD compared with controls. There were multiple positive correlations between the inflammatory markers, α-syn and markers of neuroaxonal injury (NfL and tau). In PD, higher levels of inflammatory biomarkers correlated with worse motor function and cognitive impairment. Thus, inflammatory biomarkers were increased in PDD and MSA. Furthermore, inflammatory biomarkers correlated with more severe disease regarding motor symptoms and cognitive impairment in PD, indicating an association between inflammation and more aggressive disease course. However, the results need confirmation in follow-up studies.Inflammation has been implicated in the pathogenesis of Parkinson’s disease (PD). We here investigate levels of inflammatory biomarkers in cerebrospinal fluid (CSF) in PD and atypical parkinsonian disorders (APD) compared with neurologically healthy controls. We included 131 patients with PD and 27 PD with dementia (PDD), 24 with multiple system atrophy (MSA), 14 with progressive supranuclear palsy (PSP) and 50 controls, all part of the Swedish BioFINDER study. CSF was analyzed for CRP, SAA, IL-6, IL-8, YKL-40 and MCP-1 (CCL2) as well as α-synuclein (α-syn), tau, tau phosphorylated at Thr181 (P-tau), Aβ Focus has mainly been on activated microglia and astrocytes2. However, the peripheral immune system has also been implicated3. Furthermore, increased expression of inflammatory mediators including cytokines and chemokines have been found in post mortem studies in PD4.During the last couple of decades, inflammation has gained support in the pathogenesis of Parkinson’s disease (PD)5. Post mortem and PET studies have also shown increased microglia in relevant structures in the brain of PD patients7. Evidence of activated microglia has also been found in atypical parkinsonian disorders (APD), i.e. multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD)10. The role of microglia in the onset and progression of neurodegenerative disorders such as PD remain unclear but warrants further investigations as reviewed in Gomez-Nicola and Perry11.Microglia are resident immunocompetent and phagocytic cells in the central nervous system (CNS). They can be beneficial and serve as scavengers, phagocytosing dead cells and releasing neurotrophic substances, but they can also be harmful, upregulating a variety of proinflammatory and neurotoxic substances such as reactive oxygen species and cytokines12, and GFAP-positive astrocytes have been found to correlate inversely with dopaminergic cell death in PD13. Also, α-synuclein (α-syn)-positive astrocytes have been found to correlate positively with cell death in PD14 suggesting that α-syn impairs astrocytic function. However, astrocytic activation may also in itself induce detrimental effects including increased neuroinflammation and neuronal damage15.Astrocytes are immunocompetent cells that are sensitive to proinflammatory cytokines and chemokines. They are thought to be activated as a response to injury-induced cytokine release16. A recent study found increased levels of YKL-40 in both CSF and brain tissue in patients with Alzheimer’s disease and Creutzfeldt-Jacob but unchanged in the PDD/DLB group compared with controls with neurological controls17. Other studies suggest that CSF YKL-40 concentrations are either decreased or unchanged in PD whilst CSF YKL-40 concentration may be increased in APD20. Also, interleukin (IL)-6, a cytokine involved in the acute response, might be increased in the CSF of de novo PD patients and inversely correlate with motor severity in PD21. Further, the CSF levels of CRP seem to be increased in PD patients with dementia (PDD), and correlate with depression and fatigue in patients with PD22. Our group has previously shown increased levels of IL-8 in PDD compared with controls23.Levels of inflammatory markers such as cytokines in CSF have been relatively sparsely investigated in PD and APD. YKL-40, also known as chitinase-3-like-1, is a glycoprotein that is upregulated under inflammatory conditions. In the CNS, YKL-40 is mainly expressed in astrocytes and microglia23 and to extend these by including the markers SAA and MCP-1. Further, we investigated if these markers correlate with other CSF biomarkers of importance in these disorders  as well as with cognition and/or motor function.In this cross-sectional study, we investigate further the association of the levels in CSF of acute phase proteins (CRP and SAA), IL-6 and IL-8, as well as monocyte chemotactic protein-1 (MCP-1); also called chemokine (C-C motif) ligand 2, a chemokine that is associated with microglial activation; and YKL-40 in patients with PD or APD as compared to healthy controls. We selected these markers both to replicate earlier findingswww.biofinder.se). The study participants are primarily recruited from the southern region of Sweden. In this study, we included 131 patients with PD and 27 patients with PDD. We also included 24 patients with MSA and 14 with PSP. Patients with PD met the NINDS Diagnostic Criteria for PD24. Patients with PDD met criteria for PDD at baseline25. Patients with MSA met the consensus statement26. Patients with PSP met the criteria according to the report of the National Institute of Neurological Disorders and Stroke–Society for Progressive Supranuclear Palsy International Workshop27. We also included 50 neurologically healthy controls. All controls underwent cognitive testing and neurologic examination by a medical doctor and individuals with objective cognitive or parkinsonian symptoms were not included.This study was performed at the Clinic of Neurology, Skåne University Hospital, Sweden as part of the Swedish BioFINDER Study  and patients with PSP were assessed using the PSPRS 32. The study participants’ cognitive function were assessed using e.g. the Mini Mental State Examination (MMSE), 10 word-list immediate and delayed recall test of the Alzheimer’s Disease Assessment Scale (ADAS), A Quick Test for Cognitive Speed (AQT), and the one minute phonetic verbal fluency test (Letter S Fluency test)36. The participants’ levels of anxiety, depression and fatigue were assessed using HADS and FACIT-f 38.A thorough medical history was taken and the patients underwent extensive testing, both regarding motor symptoms and cognition. Patients were examined by a physician experienced in movement disorders and a registered research nurse using, among other scales, the Unified Parkinson’s Disease Rating Scale (UPDRS) -3 and the Hoehn & Yahr scalePatients were also asked for comorbidities and any symptoms of infection during the last month and any other known medical condition associated with inflammatory response such as arthritis. Use of anti-inflammatory medication was recorded.All individuals gave written informed consent. The study procedure was approved by the local ethics committee at Lund University Sweden and conducted according to the Helsinki Declaration.39. CSF YKL-40 concentration was measured by solid phase sandwich ELISA according to the manufacturer’s instructions . CRP, SAA, IL-6, IL-8, and MCP-1 were analyzed using V-PLEX Custom Human Biomarkers kit  according to the manufacturer’s recommendations. α-syn concentration was measured using the Alpha-Synuclein ELISA Kit . Hb was analyzed using an assay provided by Bethyl lab. Inc. Total tau (T-tau), tau phosphorylated at Thr181 (P-tau), Aβ42 and NfL have previously been described40.CSF samples were obtained by lumbar puncture in the L3/L4 or L4/L5 interspace with patient non-fasting, in the morning. The samples were collected in polypropylene tubes and gently mixed to avoid gradient effects. All samples were centrifuged within 30 minutes at +4 °C at 2000 g for 10 min to remove cells and debris, and then stored in aliquots at −80 °C pending biochemical analysis. The procedure followed the Alzheimer’s Association Flow Chart for CSF biomarkersAll analyses were performed using one batch of reagents by board-certified laboratory technicians who were blinded to clinical data. For α-syn, only samples with Hb < 200 ng/L was used.et al.22 a composite score for total somatic illness was created for the most common comorbidities other than the presence of inflammatory condition  which was used as a separate covariate. Due to non-normally distributed data, ln-transformed variables were used for the univariate general linear model and regression analysis. In correlation analysis, all PD cases (including those with dementia) were included in one group. Correlations between ln-transformed CSF biomarkers as well as correlations between clinical test scores and ln-transformed inflammatory biomarkers were investigated with linear regression to correct for age, gender, disease duration, inflammatory condition and total somatic illness. Clinical test scores were ln-transformed in the case of non-normally distributed variables.Statistical analyses were accomplished with SPSS for Windows, version 22.0 . To compare demographic data between groups, we performed a Kruskal-Wallis and pairwise Mann-Whitney U-test was then used for continuous variables. For gender differences the chi-square test was used. To test for confounders, univariate associations between two continuous variables were analyzed using the Spearman’s Rho . Comparisons of CSF inflammatory biomarkers between the different diagnostic groups were first investigated with a Kruskal Wallis and pair-wise Mann-Whitney U-tests. For analysis correcting for confounders, univariate general linear models adjusting for age, gender, disease duration, inflammatory condition (n = 29) and total somatic illness were then used. As described in Lindqvist s = 0.431 and p = 0.010, Rs = 0.517, respectively). Disease duration also correlated with CRP in PDD  but not in PD or when analyzing PD and PDD together. Correcting for age, the correlation between disease duration and CRP remain in PDD . In MSA; SAA as well as IL-6 and IL-8 correlated with disease duration . However, in MSA, we also found a negative correlation between MCP1 and disease duration . Total somatic illness correlated with CRP . This correlation however was not seen in any individual diagnostic group. In the PD group, total somatic illness correlated only with YKL-40 .Demographics, clinical characteristics and levels of CSF biomarkers of study participants are given in Table Figure YKL-40 concentration in CSF was lower in non-demented PD compared with controls (p = 0.029), as well as MSA and PSP . The levels of MCP-1 in CSF were lower in PDD compared with PD (p = 0.026), MSA (p = 0.008) and PSP (p = 0.036).As shown in Table Next, we compared the CSF levels of the inflammatory markers to the CSF levels of α-syn, and the neurodegeneration markers tau, P-tau and NfL. α-syn correlated positively with SAA, IL-8 and YKL-40 in the whole group. The CSF levels of NfL correlated with CRP, SAA, IL-8, YKL-40 and MCP-1. Further, tau correlated positively with SAA, and YKL-40 but negatively with IL-6. P-tau correlated with IL-8 and YKL-40 Table .Worse results on motor function as measured by Hoehn & Yahr score correlated with CRP , SAA , IL-8  and YKL-40 . Further, very similar correlations were obtained between Parkinson’s Disease Rating Scale-3 (UPDRS-3) and CSF inflammatory markers where the UPDRS-3 score correlated with CRP , SAA , IL-8  and MCP-1 .Worse cognitive performance as measured by Mini Mental State Examination (MMSE) correlated with SAA  and IL-6 . Similar findings were observed between the CSF inflammatory biomarkers and cognitive speed and attention as measured with A Quick Test for Cognitive Speed (AQT) and Letter fluency .In PD alone, results remained significant with correlations between inflammatory markers and motor impairment with correlations between Hoehn &Yahr and CRP  and SAA . UPDRS-3 correlated with CRP  and SAA  .In PD, increased depressive symptoms as measured by the depression items of HADS and fatigue as measured by FACIT-f correlated with CRP  and SAA   . Similar results were obtained using the Unified Multiple System Atrophy Rating Scale (UMSARS) total score  with CRP and IL-8  , and neuroaxonal injury, as reflected by the tau and NfL markers.48. The present exploratory study thus needs to be confirmed in future studies.One major limitation of the study is the cross-sectional design making it impossible to address with any certainty weather inflammation and microglia activation is detrimental or beneficial. Furthermore, in comparisons between the diagnostic groups, significance levels were not corrected for multiple comparisons. This study should however be seen as an exploratory study. As suggested by Bender and Lange, correcting for multiple comparisons are required only for confirmatory studies, where the number of analyses are fewer. In exploratory studies, like the present one where relatively many analyses are performed, there would be a high risk of type 2 errors if correction for multiple comparisons was performedThe sample sizes in the APD groups were quite small and especially the PSP group may be underpowered. Also, there is a lack of neuropathological examination which is a limitation foremost in the APD group. However, in this study we have included well characterized patients and controls and they are followed over time to ascertain as accurate clinical diagnosis as possible. They are assessed regarding clinical characteristics making it possible to correlate the concentrations of biomarkers to both clinical status and disease severity. An added longitudinal study design may give information on the consistency of the inflammatory response and if the over-all duration of inflammatory response may correlate with disease progression and disease state. In conclusion, we show that inflammatory markers are increased in PDD and APD compared with controls and PD. We also show that this increase correlates with markers of neuroaxonal injury but also with motor impairment and cognitive decline. We show that YKL-40, an astroglial marker is decreased in PD, which may indicate impaired astrocytic function. We therefore suggest that inflammation and microglia may contribute to the disease processes in PD and APD. We believe that this study further contributes to the knowledge on the role of inflammation in PD and APD. However, further longitudinal studies in larger cohorts are needed.


Ro) and hydrocephalus shunt, which is a low resistance path to drain the accumulated CSF in the brain ventricles, is modeled with a resistance in series with a diode. At the end, the simulation results are shown. The simulation results can be used to predict the shunt efficiency in reducing CSF pressure and before a real shunt implementation surgery is carried out in a patient’s body.The accumulation of cerebrospinal fluid (CSF) in brain ventricles and subarachnoid space is known as hydrocephalus. Hydrocephalus is a result of disturbances in the secretion or absorption process of CSF. A hydrocephalus shunt is an effective method for the treatment of hydrocephalus. In this paper, at first, the procedures of secretion, circulation, and absorption of CSF are studied and subsequently, the mathematical relations governing the pressures in different interacting compartments of the brain are considered. A mechanical-electrical model is suggested based on the brain physiology and blood circulation. In the proposed model, hydrocephalus is modeled with an incremental resistance ( It is mainly produced in the ependymal surfaces of the Choroid plexus, and passes through the third and fourth ventricles by diffusion. It then arrives in the subarachnoid space and circulates around the brain and spinal cord. The accumulated CSF in the subarachnoid space is mainly drained in the superior sagittal sinus by arachnoid granulations. Hydrocephalus is generally defined as an excessive accumulation of CSF in subarachnoid space and brain ventricles and often results in increasing intracranial pressure (ICP)2. This accumulation causes high pressure difference above 200 mmHg and leads to serious problems in central nervous system operation.Cerebrospinal fluid (CSF) is a clear and colorless fluid that contains small quantities of glucose and protein. CSF fills the brain ventricles and the central canal of the spinal cord3. Communicating hydrocephalus is the most conventional type of hydrocephalus and occurs due to the impaired absorption of CSF without any obstruction in the CSF flow through the brain ventricles and subarachnoid space. It is theorized as an impaired function of arachnoid granulations, which are placed in the superior sagittal sinus.Depending on the physiological conditions, hydrocephalus is classified into two types: communicating and non-communicating hydrocephalus. When the flow of CSF is blocked along the narrow channels between ventricles, non-communicating or obstructive hydrocephalus occurs. Communicating or non-obstructive hydrocephalus occurs when the flow of CSF is blocked after passing through the brain ventricles4.Arachnoid granulations are the places where CSF is mainly absorbed and returns to venous blood circulation. Several neurological conditions such as intra-ventricular/subarachnoid hemorrhage, meningitis and congenital absence of the arachnoid villi would result in communicating hydrocephalus7. CSF is mainly, but not solely, produced by the choroid plexuses8. According to9, ependymal cells of the ventricles (ependyma) are other sources of CSF production. Capillaries in blood-brain barrier generate CSF, but in a very small value9. The site of this procedure is only conceptually limited to the choroid plexus of the brain ventricles. Extra-choroidal production of CSF is likely accounted for a sufficient amount of the total fluid formation in human body10. The production rate of CSF in normal conditions is reported to be fixed. Due to the lack of a direct approach to measure CSF production in short time durations, CSF secretion dynamics have not been reported correctly. Generally, the average secretion rate of CSF is about 0.35 ml/min11 and remains proportional to the brain metabolism rate.CSF is produced by active secretion from cerebral arterial blood12. It is believed that this pulsatile nature has no diagnostic significance15. CSF then moves out of the fourth ventricle through the Magendie foramen and lateral foramina of Luschka into the subarachnoid space. Afterwards, CSF flows upward to the superior sagittal sinus where it is mostly absorbed. CSF partially flows downward into the lumbar subarachnoid space. For the systolic phase of cardiac cycle, CSF moves into the spinal canal, and returns to the cranial compartment during diastole phase16.CSF, which is mainly secreted in the lateral and third ventricles, flows through the Sylvius aqueduct and arrives to the fourth ventricle. The passage through this small aperture is done rapidly and its pulsatile nature is detectable by strong dynamic MRI methods17.Accurate circulation of CSF is one of the basic mechanisms that is required for the proper operation of the central nervous system (CNS). Brain and spinal cord float in CSF, as a result, these structures would be less prone to damage in case of mechanical shocks. The free circulation of CSF results in a constant intracranial pressure. The obstruction of CSF flow between the third and fourth ventricles causes the CSF accumulation in the lateral and third ventricles. This problem is known as non-communicating (obstructive) hydrocephalus. The most causes of the obstructive hydrocephalus are congenital stenosis of the Sylvian aqueduct and neoplasms blocking the foramina. The preferred remedy for this condition is ventriculostomy in which a foramen is developed in the floor of the third ventricle until CSF can flow outIn patients with communicating hydrocephalus in which impaired flow of CSF is occurred in subarachnoid space, ventriculostomy could not be successful and shunting (placing a tube in the brain ventricle to move out the extra CSF into another place of body) is a better treatment.8. In humans, the drainage of CSF into venous system is mainly performed through arachnoid granulations. It should be noted that the inverse transport through these granulations is not possible, i.e. the drainage of CSF into the venous system is stopped if arachnoid ICP pressure becomes less than sagittal sinus pressure. The drainage of CSF into the venous system has a linear nature, i.e. the amount of CSF drainage is proportional to the pressure difference between CSF in arachnoid granulations and sagittal sinus. The inverse of the proportionality coefficient is called resistance to CSF outflow (Ro) and it ranges from 6 to 10 mmHg/ml/min or 800 to 1333 Pa in normal subjects18. On the other hand, in the proposed electrical model Ro = 1 Ω is analogous to normal conditions. Therefore, every 1 Ω in the electrical model is approximately equal to 8 mmHg/ml/min. There are various nonlinear theories that describe the reduction in Ro when the CSF drainage rate increases. All of these theories are mainly based on animal models19 or supported by measurement methods that are not very accurate20. Reducing Ro prevents the rise of ICP when CSF pressure increases.CSF is continuously secreted and absorbed in the entire CSF system due to the filtration and reabsorption of the water content through the capillary walls into the circumfluent brain tissue21; however, it is generally assumed that the spinal CSF space has a little role in the CSF drainage in comparison with the cranial compartment. Although spinal CSF transport has not been quantified directly, anatomic evidences reveal that there are several opportunities for the CSF drainage out of the spinal subarachnoid compartment22.The spinal cord contribution to the overall cranial/spinal compliance is a known phenomenonHydrocephalus usually occurs due to the obstruction of CSF outflow in the brain ventricles or in subarachnoid space over the brain. Hydrocephalus could be a result of CSF overproduction, congenital malformation in arachnoid granulations, serious head damages or brain infections. Bleeding in the subarachnoid space may also block the backward path of CSF into the circulatory system.23.Brain compression due to the accumulated CSF in ventricles may result in neurological symptoms such as epileptic, convulsion, or mental retardation seizures. Common features of hydrocephalus resulting in raised ICP are headaches, vomiting, and disturbances of consciousness. If the foramina of brain ventricles are blocked, CSF will be accumulated in the ventricles. This situation is called non-communicating hydrocephalus27. The contraction of the brain tissue often leads to irreversible brain damage. Aqueducts between the brain ventricles may be blocked at birth or after that because of a growing tumor in the brainstem.The secretion of CSF continues even if the normal pathways are blocked. Consequently, fluid produced in the brain creates a pressure, which causes dilation of brain ventricles and shrinks the brain tissueCommunicating hydrocephalus can be successfully treated by placing a thin tube (shunt) between the brain ventricles and the abdominal cavity or the right atrium during a surgical operation. Excess fluid accumulated in the brain is directed through the narrow tube into the peritoneal cavity or to the right atrium. The shunt placement may involve the risk of infection. The shunt eventually needs to be replaced when the patient grows up.31. A shunt system could also be placed in the lumbar spine to redirect the CSF into the peritoneal cavity 32. An alternative treatment for the obstructive hydrocephalus in some patients is endoscopic third ventriculostomy or ETV in which a surgically created hole in the floor of the third ventricle permits the CSF to flow directly to the basal cisterns and thereby shortcutting any obstruction17.A remedy to hydrocephalus is a surgical procedure in which a ventricular catheter (a thin tube made of silicon rubber) is placed within the ventricles of the brain to bypass the blockage of CSF outflow and drain excess CSF into the other body cavities where is absorbed in the blood circulation. Most shunts drain CSF into the peritoneal cavity , but there are alternative locations such as the right atrium , the pleural cavity  and gallbladder35. A significant amount of current literature on new shunt design focuses on refining shunt material and port orientation to prevent the occlusion or the cellular ingrowth leading to the shunt failure36. The failure rate for all hydrocephalus shunts is about 40% at the first year and 50% at the second year after the shunt insertion36.A complex problem in using an intracranial shunt in hydrocephalus treatment is the occlusion of the ventricular catheter due to the cellular ingrowthin-vivo surgical procedure.In this paper, we propose an electrical model for hydrocephalus shunt that can be used to predict shunt efficiency. In our model, we model a hydrocephalus shunt by a resistance in series with a diode. We can combine shunt parameters such as lumen diameter, material properties, and valve pressure by a resistance and a diode. This model can potentially be used to test hydrocephalus catheters prior to the In this study, we introduce an electrical model, which represents the relationship between blood, CSF, and hydrocephalus shunt. This analytical model is obtained from mechanical and biological structures in the human body.37. Compartmental volume-pressure model is conceptually shown in Fig. Pressure-volume compartmental model represents the interaction of pressures and volumes in the brain. The four components of the model are arterial volume, venous volume, brain parenchyma volume and ventricular CSF volume. The arterial volume provides blood and oxygen to the brain system through the arteries. The venous volume includes blood and other substances in the brain that leave the brain and return to the heart. The brain parenchyma volume is composed of real brain tissue (nerves and extracellular fluid) and brain capillary system. The ventricular CSF volume includes CSF volume inside the ventricular system and the entire space occupied by the ventricular systemRf). It refers to the site of CSF production in choroid plexus in the brain ventricles. CSF surrounds the brain and then moves down to reach to the subarachnoid space.Blood circulation in the brain from arteries to other parts such as capillaries and veins is shown in Fig. Ro in Fig. Ro increases). In a shunt surgery for hydrocephalus treatment, Ro is actually bypassed and a low-resistance path (Rshunt), in its parallel, is created to drain the excess CSF that has accumulated in the ventricles of the brain into the right atrium or peritoneal cavity. Electrical equivalent circuit of Fig. CSF is mainly absorbed through the venous system in the sagittal sinus. This path is usually modeled by resistance 38. Secondly, two sine wave with frequency of 1 Hz and 2 Hz are subtracted to obtain a pressure waveform similar to arterial blood pressure in the brain39. Thus, the sinusoidal waveform for the pressure within the brain is achieved as follows:To obtain various pressures in the compartmental model, at first, an electrical model corresponding to different parts of the brain system and their communication with each other is extracted using Simulink softwareIn the equivalent circuit shown in Fig. a, v, tiss, and CSF refer to the arterial system, venous system, brain parenchyma and ventricular system volumes of the brain, respectively40. The above equation means that changes in the brain volume is zero, i.e. brain volume is fixed. In other words, a part of the brain tissue can enlarge in size , only if another part compresses.With the pressures shown in Fig. Cai represents the compliance between arterial compartment and intracranial site, Cvi represents the compliance between venous compartment and intracranial site, and Ctiss represents compliance of the brain tissue. Also, Pa, Pc, Pv, Pic, and Pvs are arterial pressure, capillary pressure, venous pressure, intracranial pressure and pressure difference between arachnoid villi and sagittal sinus, respectively.The volume of separate compartments of the brain is described with an equation that expresses the human brain intracranial dynamics:P symbolizes the pressure and q represents the flow rate in mL/sec. For laminar flow in a tube, Poiseuille’s law for resistance states that41:μ is the Newton viscosity, l is the length of the tube, and r is the inner radius of the tube. In other words, resistance in the fluid flow results from physical aspects of the tube and the fluid.The circuit shown in Fig. Rshunt.Therefore, various shunt configurations with different parameters such as lumen diameter, material properties, port configuration, and valve pressure could be considered in the resistance Ro = 1 Ω (8 mmHg/ml/min). Then the hydrocephalus conditions were simulated for various degrees of hydrocephalus, i.e. moderate hydrocephalus Ro = 5 Ω (40 mmHg/ml/min) and severe hydrocephalus Ro = 10 Ω (80 mmHg/ml/min). In Fig. 42.We add this model to the electric circuit in Fig. 42. Arterial pressure (Pa) is the largest and closest waveform to the heart source. The next largest waveform is capillary pressure Pc. As pressure waveform propagates through the brain, it travels from arteries to capillaries. As it is clear from the graphs, when pressure waveform goes away the arteries, it will be significantly weakened43. Elasticity of arteries walls absorbs kinetic energy of pressure waveform and decreases its magnitude. After passing through the capillaries, blood goes into the venous system where pressure waveform is further weakened Pv. Here blood in the brain returns to the heart and lungs for recycling and purification43.The pressure waveforms in different parts of the brain follow the pulsatile nature of the blood pressure. Since each of these waveforms relates to different places in the brain, they will vary in amplitude and phasePa) depending on the value of absorption resistance. Hydrocephalus is simulated with increased resistance in the way of absorption of CSF from the ventricular system to its entry into the venous system. In the electrical circuit shown in Fig. When hydrocephalus occurs, the magnitude of pressure waveforms varies  and Ro = 10 Ω (80 mmHg/ml/min), are illustrated in Figs Ro) in case of hydrocephalus. Also, the higher degree of hydrocephalus (larger selected Ro in the model), makes the pressure become greater. However, to simulate the effect of hydrocephalus shunt, we choose the value of Rshunt in proposed model in Fig. The waveform of arterial, capillary, and venous pressures along with the pressure difference between the arachnoid villi and sagittal sinus in normal conditions have been shown in Fig. We define shunt efficiency as Eq.  in belowBy this definition, a shunt with efficiency of 90% has a resistance of about Rshunt which are responsible for different shunt efficiencies.ICP values from simulation results have been illustrated in Fig. 48. However, Marmarou was one of the first49 who integrated CSF production, circulation, absorption, and storage in a suitable theoretical formulation expressed as an electrical model. The mathematical model of cerebrospinal fluid (CSF) pressure volume compensation, introduced by Marmarou in 1973 and modified in later studies, provides a theoretical basis for various diagnosis in hydrocephalus50.Many theoretical/modeling studies on CSF dynamics were published before the 1970sIn this study, an analytical model, as a modified version of Ursino model, has been provided to simulate hydrocephalus shunt along with the dynamics of CSF production and circulation. In patients with hydrocephalus, the amount of CSF within the brain ventricles is increased and leads to an increase in ICP value in which the brain tissue is severely affected. Various neurological conditions such as intra-ventricular hemorrhage, bleeding in the subarachnoid space, meningitis and congenital absence of the arachnoid villi may cause hydrocephalus. The most common method for hydrocephalus treatment is shunting.A CSF shunt involves a bypass pathway for drainage of CSF, which accumulated in the brain due to blockage in the path of CSF drainage or the poor functioning of the arachnoid villi. Electrical modeling of hydrocephalus shunting along with CSF dynamics has several advantages. This modeling may lead to a better understanding of the physiology of the disease, especially the changes that occur by the use of a CSF shunt could be observed truly. Electrical model provides a possibility for testing the shunt non-invasively. Also, it provides possibility of checking out a wide range of parameters needed to design a shunt valve before the equipment to be made. Modeling can also help to predict the efficiency of the shunt.in-vivo surgical procedure. The method may contribute to the selection of better material and also better physical structure for the shunt that is to be implanted in the patient’s body.In this paper, an electrical model has been proposed for hydrocephalus shunt that can be used to predict shunt efficiency. In the model, a hydrocephalus shunt can be modeled by a resistance in series with a diode. Shunt parameters such as lumen diameter, material properties, and valve pressure can be combined by a resistance and a diode. This model can potentially be used to test hydrocephalus catheters prior to the We know that Newtonian fluid flow through a tube assimilates an electronic current flow in a resistor in which the fluid flow is analogous to electrical current and the fluid pressure to voltage. Based on Eq. Therefore, various shunt configurations with different parameters such as lumen diameter, material properties, port configuration, and valve pressure could be considered in the resistance value. Therefore, using Eq. In this study, the value of shunt resistance is assumed linear and time invariant, but shunt resistance may behave nonlinearly and time variant for some reasons such as shunt tube obstruction, disruption of shunt valve control system  and reducing the diameter of the shunt tube over time as a result of material deposition. To include these cases in the study, shunt resistance was considered as a non-linear and time variant that represented by Eq. The intracranial pressure (ICP), based on Eq. a), capillary (Pc), and venous (Pv) pressures for this conditions.As shown in Fig. 1 in electrical model in Fig. In Fig. 52. In our model, we did not consider this component that is believed to have a role in CSF absorption. For a complete model, it may be considered. Certainly, experimental studies are required to validate our model.It is necessary to mention that the model proposed in this paper has some limitations. In our electrical model in this paper, for simplicity we ignored the role of spinal cord compartment, but we suggest that the role of spinal cord compliance in CSF dynamics be considered to achieve a complete model. Also, some literatures reveal that a significant absorption of CSF in subarachnoid space may occur by lymphatic vessels53. Thus, postural change effects could be included in the proposed electrical model by inserting a variable component in the voltage supply in Fig. Ctissue in the model of Fig. Although, there are several animal models in which the standard shunts examined and tested, but these models cannot approximate CSF production, postural changes and brain size that happen to human. The postural changes effect on blood pressure consists of a fall as the patient stands up, and a rise when the patient lays downin-vivo surgical procedure. The method may contribute to help surgeon to select better material and also better physical structure for the shunt that is to be implanted in the patient’s body.In the treatment of hydrocephalus, a shunt is used to drain additional CSF from the brain ventricles into an elsewhere in the body. In this paper, an electrical model has been proposed for hydrocephalus shunt that can be used to predict shunt efficiency. In our model, we model a hydrocephalus shunt by a resistance in series with a diode. We can combine shunt parameters such as lumen diameter, material properties, and valve pressure by a resistance and a diode. This model can potentially be used to test hydrocephalus catheters prior to the


Clostridium difficile infection (rCDI) is the most common cause of hospital- and community-acquired diarrheal infection associated with antibiotic use. Fecal microbiota transplantation (FMT), a treatment that involves administration of fecal bacteria from a healthy donor to a recipient patient, is a highly effective rescue therapy for rCDI that is increasingly being incorporated into standard clinical practice. Encapsulated, freeze-dried preparations of fecal microbiota, administered orally, offer the simplest and most convenient route of FMT delivery for patients (cFMT). In this study, we evaluated the extent of bacterial engraftment following cFMT and the duration of donor bacterial persistence. All patients studied recovered clinically but showed differing patterns in long-term microbial community similarity to the donor that were associated with members of the bacterial group Bacteroidetes, previously shown to be prominent contributors to rCDI resistance. Results highlight long-lasting, donor-specific effects on recipient patient microbiota and reveal potential bacterial targets to improve cFMT engraftment.Recurrent  Clostridium difficile infection, and encapsulated delivery (cFMT) of healthy donor microbiota shows similar clinical efficacy as more traditional routes of administration. In this study, we characterized long-term patterns of bacterial engraftment in a cohort of 18 patients, who received capsules from one of three donors, up to 409 days post-FMT. Bacterial communities were characterized using Illumina sequencing of the V5-V6 hypervariable regions of the 16S rRNA gene, and engraftment was determined by using the Bayesian algorithm SourceTracker. All patients recovered clinically and were free of C. difficile infection following cFMT. The majority of patients (61%) showed high levels of engraftment after the first week following FMT, which were sustained throughout the year. A small subset, 22%, experienced a decline in donor engraftment after approximately 1 month, and a few patients (17%), two of whom were taking metformin, showed delayed and low levels of donor engraftment. Members of the genera Bacteroides, Parabacteroides, and Faecalibacterium were significantly and positively correlated with donor similarity . Furthermore, throughout the year, patient fecal communities showed significant separation based on the donor fecal microbiota that they received (P < 0.001). Results of this study, which characterize long-term engraftment following cFMT, suggest that numerical donor similarity is not strictly related to clinical outcome and identify a persistent donor-specific effect on patient fecal microbial communities. Furthermore, results suggest that members of the Bacteroidetes may be important targets to improve engraftment via cFMT.Fecal microbiota transplantation (FMT) has become a common rescue therapy for recurrent  Clostridium difficile , in particular, present a major clinical problem and continue to increase in incidence  than would be expected given normal, interpersonal variability (x̄ = 77.4%), and engraftment persisted through a 1-year follow-up , changed significantly at 2 to 6 days post-FMT , and was not statistically different from donor samples after the first week . However, significantly greater similarity was observed when all three donors were assigned as a single potential source (“combined donor”) than when only the empirically administered donor  sample was used (P < 0.0001).SourceTracker software, which uses a Bayesian algorithm to determine the percentage of the community in user-defined sink (patient) samples that is attributable to source (donor) communities, was used to measure bacterial engraftment. The percentage of donor engraftment, from individual donor lots, increased significantly from days 2 to 6 to days 28 to 45 post-FMT (Bacteroides (12.27% ± 0.03% of sequence reads), Blautia (5.52% ± 0.01%), Parabacteroides (4.29% ± 0.01%), Roseburia (3.30% ± 0.01), and Faecalibacterium (2.95% ± 0.01%), corresponding to changes observed in community composition over time , results from both methods of analysis were highly correlated . A similar percentage of shared OTUs was observed among patients who received capsules from either donor 6 or donor 41, although communities in patient samples who received capsules from donor 6 showed a greater percentage of shared OTUs at 7 to 21 and 86 to 134 days post-FMT .In order to validate SourceTracker results, donor similarity was also determined using the abundances of operational taxonomic units (OTUs) that were empirically shared between donor 6 or 41 and patient samples . While tP = 0.599). However, microbial communities from patient samples collected at least 1 month post-FMT showed similar composition as that of the donor lot that the patients received and were significantly different from patients receiving lots from other donors .The donor production lot (from a single stool) used for capsule preparation did not significantly influence the percentage of engraftment at the year-end time point . Pairwise differences in genus abundances, however, were not significant among the engraftment patterns at the same time point (post hoc P > 0.05). Similarly, differences in alpha diversity at the year time point did not vary significantly among the groups (P ≥ 0.464).Spearman correlation analysis, done among all samples, further revealed significant positive correlations between the relative abundances of Bacteroides by using oligotype analysis. This analysis uses single nucleotide polymorphisms of 16S rRNA to identify likely strains within a target genus, offering greater resolution than that seen with OTU binning , and significantly fewer oligotypes were observed in pre-FMT samples relative to donors (P < 0.0001). Typically, oligotype diversity expanded in patient samples following cFMT, but usually only 2 to 4 engrafted  after 1 week following cFMT, which was typically sustained throughout the year. This is similar to the previous report on 14 Finnish patients who received colonoscopic FMT, where recipient intestinal microbiota remained highly correlated (>90%) with that of the donor over 1 year . HoweverC. difficile  by which FMT results in clinical recovery has only been partially elucidated  and likeifficile , 26. We ifficile . In thishy state . While thy state ; complexhy state ; niche ehy state ; and stoBacteroidetes, as well as the distribution of Bacteroides oligotypes, showed the greatest association with engraftment. Members of this genus were previously shown to be the primary component of the incremental response following cFMT  and was then administered methenamine hippurate (Hiprex) for UTI suppression, which may have also interfered with engraftment. Two patients (R67 and R68) received topical antibiotics following cFMT , which did not seem to have a significant impact on bacterial engraftment. Along these lines, two of three patients taking metformin, prior to and throughout the course of the study, showed considerably lower and delayed engraftment compared to others, while the third seemed unaffected. Metformin was previously shown to alter intestinal microbiota composition , 37. FutResults of this study highlight different patterns of long-term bacterial engraftment following cFMT, exclusive of clinical recovery. Notably, taxonomic similarity to the donor did not seem to influence patient recovery, although an overall donor-specific influence on taxonomic composition separated patient communities up to a year following FMT. This study was limited by a small sample size, which may not have captured all possible post-FMT patterns of engraftment. We considered many clinical factors that may have significant impact on the composition of intestinal microbiome, including various medications, history of abdominal surgery , and metabolic factors such as obesity, all of which are encountered in this very complex patient population; however, their contribution could not be resolved given the study size. Also, we did not collect systematic dietary data following cFMT treatment. Further, our study focused only on bacterial community composition, although fungal and viral communities have also shown variable engraftment kinetics associated with FMT response , 38, 39.−2. Health care workers are excluded from the donor program because of the potential risk of colonization with multidrug-resistant organisms. The stool was tested for viral, bacterial, and parasitic enteric pathogens, as well as vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, and bacteria containing extended-spectrum beta-lactamases, which constitute part of the release criteria prior to clinical use. All donor activities, which include administration of questionnaires, physical exams, and laboratory testing, are approved by the University of Minnesota Institutional Review Board.All stool donors qualified in accordance with the strict inclusion and exclusion criteria described previously  and in a2 gas, sieved to remove large particles of >0.25 mm, amended with 5% trehalose, and freeze-dried. Each course of capsules represented only one fecal donation, and capsules were stored at −80°C prior to distribution to patients. Patients who received capsules from donor 6 took four capsules once representing a dose of 5 × 1011 cells, those who received capsules from donor 41 took two capsules once representing a dose of 2.1 × 1011 cells, and the patient who received capsules from donor 44 took four capsules once representing a dose of 2.5 × 1011. Differences in donor and dosage were previously reported not to affect cFMT efficacy  to a 30-ml polystyrene fecal specimen container . Samples were stored in the patients’ freezers prior to transfer on ice to the lab, where they were held at −20 to −80°C until DNA extraction. Sample collections were taken prior to cFMT (pre-FMT) and up to 409 days post-FMT. Due to the uneven nature of sample collection, samples were binned to the following day group ranges: 2 to 6 days, 7 to 21 days, 28 to 45 days, 86 to 134 days, and 346 to 409 days post-FMT, in correspondence with our previous studies , 18.DNA was extracted from approximately 0.25-g aliquots of thawed stool samples by using the DNeasy PowerSoil extraction kit  and the automated QIAcube platform . The V5-V6 hypervariable regions of the 16S rRNA gene were amplified using the BSF784/1064R primer set . IlluminSequence processing was done by using mothur software ver. 1.35.1  and a prSourceTracker ver 0.9.8  was usedBacteroides populations of patients, oligotyping was done using version 2.1 software and suggested best practices . All statistics were evaluated at α = 0.05, with Bonferroni correction for multiple comparisons.Good’s coverage estimate and the Shannon index  were calSRP070464.Raw sequence data are deposited in the Sequence Read Archive of the National Center for Biotechnology Information under BioProject accession number


Vinorelbine is known to be effective in the treatment of non-small cell lung cancer and breast cancer. However, venous irritation is a common side effect. Although there have been some reports on risk factors for venous irritation in patients receiving vinorelbine, the factors evaluated have been limited and the results inconclusive. The aim of this study was to identify risk factors for venous irritation in patients receiving vinorelbine, and factors likely associated with venous irritation, including new factors such as hot compress with a hot towel  for prevention of venous irritation.We retrospectively reviewed patients treated with vinorelbine at Kyorin University Hospital, Japan, between March 2013 and December 2016 and divided them into the two groups according to whether or not they had venous irritation. Clinical characteristics were compared between the two groups.p = 0.035). Low body surface area was also the only significant risk factor for vinorelbine-associated venous irritation in multivariate analysis . There was no association between the occurrence of venous irritation and the other covariates, such as use of a hot compress, history of diabetes mellitus, or use of a generic formulation of vinorelbine.Venous irritation occurred in 24 (38.1%) of 63 patients who received vinorelbine. The median number of times vinorelbine was administered before onset of venous irritation was 3 (range 1–14). The group with venous irritation had a significantly lower body surface area than the group without venous irritation (Low body surface area may be a risk factor for venous irritation in patients receiving vinorelbine. Use of hot compress with a hot towel did not prevent venous irritation. Venous irritation is one of the discomforting toxicities that can occur with peripheral intravenous therapy. Various drugs can induce venous irritation when administered via peripheral venous infusion, and the osmolality and pH of the solution are reported to influence the likelihood of venous irritation . MoreoveVinorelbine (VNR) is a vinca alkaloid-derived anticancer drug that has antitumor activity against non-small cell lung cancer and breast cancer –7. AlthoThe aim of this study was to analyze the risk factors for venous irritation in patients receiving VNR, including preventive use of hot compress with a hot towel and use of a generic formulation.http://www.kyorin-u.ac.jp/hospital/clinic/pdf/yakuzaibuekigakutyuousa.pdf).This retrospective study involved patients who received administered VNR at Kyorin University Hospital between March 2013 and December 2016. Outcomes were assessed from March 2013 to February 2017. One patient who received both branded and generic formulations of VNR was excluded. The study protocol was approved by the Ethics Committee of Kyorin University Hospital  and was conducted in accordance with the Declaration of Helsinki. The need for informed consent was waived in view of the retrospective and observational nature of the study. An opt-out approach was used with the disclosure of website (URL: 2 is decreased to 20 mg/m2 when combined with cisplatin (CDDP) because radiation therapy is administered concurrently. VNR is usually administered via the main route, but is administered via a side port in this department. VNR was diluted by 50-mL physiologic saline in all patients. After administration of VNR, a 250-mL washout infusion of physiologic saline is administered. On day 1 of each cycle of VNR + CDDP, CDDP was administered following VNR rather than the washout infusion of physiologic saline. Mannitol was administered as a diuretic in all patients who received VNR + CDDP. In March 2016, Kyorin University Hospital switched from the branded formulation of VNR  to a generic formulation .In all regimens, VNR was administered on days 1 and 8 of each treatment cycle. In the Department of Respiratory Medicine, the usual VNR dose of 25 mg/mA hot towel was applied as a hot compress when VNR was administered in the Department of Thoracic Surgery. The area on the trunk near the administration site was warmed with the hot towel from about 10 min before administration of VNR to the end of the infusion. The hot towel was warmed to about 60°C in a towel steamer .We collected data on patient characteristics and occurrence of venous irritation and divided the patients into a venous irritation group and a non-venous irritation group. The diagnosis of venous irritation was made by the attending physician. The subspecialty of each attending physician was thoracic surgery, respiratory medicine, or breast surgery. The incidence of venous irritation was recorded from the first day of administration of VNR to the end of the treatment course. The following patient demographic and clinical data were collected from electronic medical and pharmacy records and compared: age, sex , body surface area, body mass index (≥ 25 or < 25), regimen (single or combination), department (respiratory medicine or surgery), VNR dose (≥ 40 or < 40 mg), route of administration (via side port or main route), drug formulation (branded or generic), history of diabetes mellitus (yes or no), premedication dose of dexamethasone, and use of hot compress with a hot towel (yes or no).t-test or Mann-Whitney U test as appropriate. Categorical variables were compared using Fisher’s exact test. Variables with a p-value < 0.25 in the univariate analysis were then directly entered into the multivariate logistic regression model. Statistical analysis was performed using EZR version 1.35 software  [p-value < 0.05 was considered statistically significant.Continuous variables were compared between the group with venous irritation and the group without venous irritation using the Student’s Austria) . A p-valThe clinical and demographic characteristics of the 63 patients  who received VNR during the study period are shown in Table Venous irritation occurred in 24 38.1%) of the 63 patients who received VNR during the study period. Fig. % of the p = 0.035; Table p = 0.188). There was no association between likelihood of developing venous irritation and body mass index, VNR dose, use of a side port as the route of administration, use of a generic formulation, or history of diabetes mellitus. Use of hot compress with a hot towel did not prevent venous irritation (p = 0.124). When factors with a p-value < 0.25  were analyzed in multivariate analysis, only body surface area remained as a statistically significant predictor of the risk for venous irritation  of the 63 patients in this study. This incidence is higher than the incidence of 3.7–18.7% cited in the package insert . Venous Yoh et al. reported that a high body mass index increased the risk of venous irritation while Yamada et al. reported that the risk was increased when a VNR dose ≥ 40 mg was administered , 11. In There are several limitations to this study, First, the study had a retrospective and single-center design, a small sample size, and potential for patient selection bias. Second, we could not evaluate who secured venous access or the location of the puncture site. Furthermore, we reviewed only factors that were potentially associated with venous irritation, and further research is needed to investigate injection site reactions.In this study, body surface area was the only statistically significant predictor of the risk of venous irritation in patients receiving VNR. Hot compress using a hot towel did not prevent venous irritation. Prospective studies are needed to identify the most significant risk factor for venous irritation associated with VNR.