Indiana University-Purdue University Indianapolis (IUPUI) / Hydrocephalus is a medical condition characterized by a buildup of cerebrospinal fluid which causes hydrostatic pressure to increase resulting neuronal destruction and can ultimately cause death. Hydrocephalus is seen in both the pediatric population and adults. Treatment of hydrocephalus usually involves surgical placement of a relocation system to drain the fluid into the abdominal cavity. Hydrocephalus may be caused by mechanical obstruction of the outflow of CSF from the ventricles or by faulty reabsorption. It can be also caused by CSF overproduction by the choroid plexus found in the lateral, third, and fourth ventricles of the brain. The choroid plexus is composed of a high resistance monolayer epithelium which surrounds a network of capillaries. Its primary function is to regulate transport of ions and water that control the production and movement of CSF. Therefore it is important to understand the mechanism of CSF production by the choroid plexus. Recently, a stable porcine choroid plexus (PCP-R) epithelial cell line with a high transepithelial resistance (TER) was developed that provides an important model to study regulation of CSF production. Ussing style electrophysiology was used to measure short circuit current (SCC) to characterize stimulated transepithelial ion transport in confluent PCP-R cells. GSK1016790, a TRPV4 agonist, was used to understand the role of TRPV4 in CSF production by the choroid plexus using PCP-R cell model. TRPV4 activation produces a sustained ion transport response that is consistent with an increase in cation secretion and/or anion absorption which is accompanied by a reversible decrease in TER. The effect of the agonist on both SCC and TER was blocked by HC067047, a TRPV4 antagonist, showing that the sustained ion transport and TER change is TRPV4 specific. TRPV4 mediated ion flux was inhibited by CFTR inhibitor II GlyH-101, a cell permeable inhibitor of the cAMP activated chloride channel CFTR, when added on either side of the membrane and was not accompanied by a TER reversal which showed that CFTR is activated by TRPV4 mediated ion flux. TMEM16A, a calcium activated chloride channel, was speculated to be located in that basal membrane as T16Ainh-AO1, a membrane permeable TMEM16A inhibitor, reversed the TRPV4 mediated ion flux when added on either side of the membrane. Slight reversal in TER was observed when T16Ainh-AO1 was added on the apical side. Apamin, a differential inhibitor of calcium activated small conductance potassium channel 1, 2 and 3 (SK1, SK2 and SK3) had no effect on the TRPV4 mediated ion flux. Whereas, fluoxetine, a membrane permeable inhibitor of SK1, SK2 and SK3 channel, inhibited the TRPV4 mediated ion flux and TER change. Bumetanide, an inhibitor of the sodium-potassium-chloride cotransporter reversed TRPV4 mediated ion flux when added on the apical membrane but not on the basal membrane indicating a possible K+ secretion via SK1 and/or SK4/IK channels and Cl- absorption through CFTR and TMEM16A channels. Acetazolamide, a carbonic anhydrase inhibitor and a compound used to treat hydrocephalus had no effect on the TRPV4 mediated ion flux. cAMP is an intracellular mediator involved in neuromodulator effects, inflammatory responses and other regulatory mechanisms and is constitutively activated by forskolin. In PCP-R cells, forskolin stimulated an increase in transepithelial ion flux that is consistent with an increase in cation absorption and/or anion secretion. Forskolin mediated ion transport was inhibited by CFTR inhibitor II GlyH-101 when added on either side of the membrane. No change in TER was observed. No effect on forskolin mediated ion flux was observed when T16Ainh-A01, apamin or fluoxetine were added. Forskolin stimulated transport is partially inhibited by 1 mM BaCl2. Barium chloride is a general inhibitor of K+ channels. No change in TER was observed.

No description available.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Pediatric hydrocephalus is a complex neurological condition associated with a pathological accumulation of cerebrospinal fluid (CSF), typically within the brain ventricular system. Pediatric hydrocephalus can be primary (due to genetic abnormalities or idiopathic causes), or secondary to injuries such as hemorrhage, trauma, or infection. The current permanent treatment paradigms for pediatric hydrocephalus are exclusively surgical and include the diversion of CSF via shunt or ventriculostomy. These surgical interventions are wrought with failures, burdening both the United States healthcare system and patients with repeat neurosurgical procedures. Thus, the development of nonsurgical interventions to treat hydrocephalus represents a clinically unmet need. To study hydrocephalus, we use a genetic rat model of primary neonatal hydrocephalus, the Tmem67P394L mutant. In several proof-of-concept studies, we identify antagonism of the transient receptor potential vanilloid 4 (TRPV4) channel and associated upstream regulatory kinase, serum-andglucocorticoid-induced kinase 1 (SGK1) as therapeutics for the treatment of hydrocephalus. Using in vitro models of the choroid plexus epithelium, the tissue which produces CSF, we show compelling proof-of-mechanism for TRPV4 antagonism and SGK1 inhibition at preventing CSF production. Therefore, the studies in this dissertation provide substantive evidence on the role of TRPV4 in the choroid plexus in health and disease.

It was generally accepted that the rate of formation of cerebrospinal °uid (CSF) is independent of intraventricular pressure [26], until A. Sahar and a host of other scientists challenged this belief. A. Sahar substantiated his belief that the rate of (CSF) formation actually depends on intraventricular pressure, see A. Sahar, 1971 [26]. In this work we show that CSF formation depends on some other factors, including the intraventricular pressure. For the purpose of this study, we used the capillary blood °ow model proposed by K.Boryczko et. al., [5] in which blood °ow in the microvessels was modeled as a two-phase °ow; the solid and the liquid volume phase. CSF is formed from the blood plasma [23] which we assume to be in the liquid volume phase. CSF is a Newtonian °uid [2, 23]. The principles and methods of e®ective area" developed by N. Sauer and R. Maritz [21] for studying the penetration of °uid into permeable walls was used to investigate the ¯ltrate momentum °ux from the intracranial capillary wall through the pia mater and epithelial layer of the choroid plexus into the subarachnoid space. We coupled the dynamic boundary equation with the Navier-Stoke's constitutive equation for incompressible °uid, representing the °uid °ow in the liquid volume phase in the capillary to arrive at our model. / Mathematical sciences / M.Sc.

It was generally accepted that the rate of formation of cerebrospinal °uid (CSF) is independent of intraventricular pressure [26], until A. Sahar and a host of other scientists challenged this belief. A. Sahar substantiated his belief that the rate of (CSF) formation actually depends on intraventricular pressure, see A. Sahar, 1971 [26]. In this work we show that CSF formation depends on some other factors, including the intraventricular pressure. For the purpose of this study, we used the capillary blood °ow model proposed by K.Boryczko et. al., [5] in which blood °ow in the microvessels was modeled as a two-phase °ow; the solid and the liquid volume phase. CSF is formed from the blood plasma [23] which we assume to be in the liquid volume phase. CSF is a Newtonian °uid [2, 23]. The principles and methods of e®ective area" developed by N. Sauer and R. Maritz [21] for studying the penetration of °uid into permeable walls was used to investigate the ¯ltrate momentum °ux from the intracranial capillary wall through the pia mater and epithelial layer of the choroid plexus into the subarachnoid space. We coupled the dynamic boundary equation with the Navier-Stoke's constitutive equation for incompressible °uid, representing the °uid °ow in the liquid volume phase in the capillary to arrive at our model. / Mathematical sciences / M.Sc.

O Câncer colorretal (CCR) é um problema de saúde importante devido a sua incidência e mortalidade elevadas. O rastreamento e o diagnóstico precoce são a principal estratégia para diminuir a mortalidade pelo CCR. A colonoscopia convencional (CC), constitui o melhor método para o diagnóstico precoce do CCR e para o diagnóstico e tratamento das lesões precurssoras. Entretanto a CC apresenta taxas de falha de detecção não desprezíveis. A colonoscopia com magnificação de imagem (CM), vem sendo utilizada com o intuito de melhorar a performance da CC. A sua principal vantagem é a possibilidade de diferenciar lesões neoplásicas de não-neoplásicas, de maneira que apenas lesões neoplásicas seriam retiradas, diminuindo custos e riscos relacionados ao rastreamento por colonoscopia. O objetivo deste estudo é determinar a acurácia da CM para o diagnóstico diferencial entre lesões neoplásicas e não-neoplásicas do intestino grosso por meio da comparação entre o diagnóstico endoscópico e o fornecido pelo exame histopatológico convencional. Entre abril de 2002 e outubro de 2003, cento e vinte pacientes foram incluídos no estudo, tendo-se encontrado 200 lesões. Todas as lesões foram classificadas endoscopicamente através da CM com alta magnificação (até 200X), associada a cromoscopia com índigo carmim, de acordo com a classificação proposta por Kudo, e em seguida excisadas ou biopsiadas para estudo histopatológico. A acurácia da determinação do diagnóstico diferencial endoscópico em relação à histopatologia entre lesões neoplásicas e não-neoplásicas foi de 78,5%. A diferença da CM em relação ao exame histopatológico foi estatisticamente significativa (p<0,0001). Conclui-se que, no atual estágio de desenvolvimento, a CM, pela sua acurácia, não permite excluir o exame histopatológico para o diagnóstico diferencial entre as lesões neoplásicas e não-neoplásicas do intestino grosso. / Bacterial meningitis in the neonatal period is a severe disease, associated to elevated mortality and sequelae in around 12 to 29% of the survivors. Newborns whose birth weight is < 2,500g have a 3-fold increase in the risk of acquiring meningitis when compared to those whose weight is > or = 2,500; among those with very low birth weight (< 1,500g), the risk increases 17-fold. Objectives: General: to describe the clinical picture and the complications of bacterial meningitis in two groups of newborns, considered according to birth weight (< 2,500g or > or = 2,500g). Specific: to describe and compare the etiological agents, the frequency of neurological signs and symptoms and complications, mortality rate and duration of treatment in both groups. Methods: Observational study of 87 newborns with bacterial meningitis, admitted at the Neonatal Intensive Care Unit (NICU) of Instituto da Criança of Hospital das Clínicas of the University of São Paulo School of Medicine, during an 11-year period (January 1994 to December 2004). The data were obtained through the analysis of hospital files. Statistical analysis was carried out with Fisher\'s exact test and the non-parametric Mann Whitney test. Results: Bacteria were identified in the cerebrospinal fluid (CSF) of 39% of the patients, with 50% of them being Gram-positive and 50%, Gram-negative. Most neonates presented unspecific signs and symptoms: fever (63.2%), irritability (31%), and lethargy (26.4%). The neurological findings occurred in 35.3% of the cases. Complications occurred in 48.2% of the neonates, and were mainly seizures (23%), intracranial hemorrhage (14.9%) and hydrocephalus (13.8%) with a mortality rate of 11.5%. At the comparison between clinical evolution and birth weight, associations between weight > or = 2,500g and seizures (p=0.047), weight > or = 2,500g and concave fontanel (p=0.019), bacteria in the CSF and complications (p=0.008) and bacteria in the CSF and death (p=0.043) were observed. Conclusions: The etiological agents most often identified in the CSF were enterobacteria (41%), followed by B Streptococcus (17.5%), non-B Streptococcus (17.5%), Staphylococcus aureus (11.7%), Neisseria meningitidis (8.8%) and Enterococcus faecalis (3.0%), with no statistical difference between the type of bacteria and birth weight. The predominant signs and symptoms were unspecific, with neurological findings in 35% of the cases. The higher frequency of neurological signs and symptoms in newborns with birth weight > or = 2,500g suggest a higher degree of central nervous system maturity in these infants. Although the mortality was lower than that observed in previous studies at the same Service, the frequency of complications was high, regardless of birth weight. The presence of bacteria in the CSF was associated to a higher frequency of seizures and mortality. The need for prolonged treatment in newborns with low birth weight suggests higher disease severity in this group of neonates.

O Câncer colorretal (CCR) é um problema de saúde importante devido a sua incidência e mortalidade elevadas. O rastreamento e o diagnóstico precoce são a principal estratégia para diminuir a mortalidade pelo CCR. A colonoscopia convencional (CC), constitui o melhor método para o diagnóstico precoce do CCR e para o diagnóstico e tratamento das lesões precurssoras. Entretanto a CC apresenta taxas de falha de detecção não desprezíveis. A colonoscopia com magnificação de imagem (CM), vem sendo utilizada com o intuito de melhorar a performance da CC. A sua principal vantagem é a possibilidade de diferenciar lesões neoplásicas de não-neoplásicas, de maneira que apenas lesões neoplásicas seriam retiradas, diminuindo custos e riscos relacionados ao rastreamento por colonoscopia. O objetivo deste estudo é determinar a acurácia da CM para o diagnóstico diferencial entre lesões neoplásicas e não-neoplásicas do intestino grosso por meio da comparação entre o diagnóstico endoscópico e o fornecido pelo exame histopatológico convencional. Entre abril de 2002 e outubro de 2003, cento e vinte pacientes foram incluídos no estudo, tendo-se encontrado 200 lesões. Todas as lesões foram classificadas endoscopicamente através da CM com alta magnificação (até 200X), associada a cromoscopia com índigo carmim, de acordo com a classificação proposta por Kudo, e em seguida excisadas ou biopsiadas para estudo histopatológico. A acurácia da determinação do diagnóstico diferencial endoscópico em relação à histopatologia entre lesões neoplásicas e não-neoplásicas foi de 78,5%. A diferença da CM em relação ao exame histopatológico foi estatisticamente significativa (p<0,0001). Conclui-se que, no atual estágio de desenvolvimento, a CM, pela sua acurácia, não permite excluir o exame histopatológico para o diagnóstico diferencial entre as lesões neoplásicas e não-neoplásicas do intestino grosso. / Bacterial meningitis in the neonatal period is a severe disease, associated to elevated mortality and sequelae in around 12 to 29% of the survivors. Newborns whose birth weight is < 2,500g have a 3-fold increase in the risk of acquiring meningitis when compared to those whose weight is > or = 2,500; among those with very low birth weight (< 1,500g), the risk increases 17-fold. Objectives: General: to describe the clinical picture and the complications of bacterial meningitis in two groups of newborns, considered according to birth weight (< 2,500g or > or = 2,500g). Specific: to describe and compare the etiological agents, the frequency of neurological signs and symptoms and complications, mortality rate and duration of treatment in both groups. Methods: Observational study of 87 newborns with bacterial meningitis, admitted at the Neonatal Intensive Care Unit (NICU) of Instituto da Criança of Hospital das Clínicas of the University of São Paulo School of Medicine, during an 11-year period (January 1994 to December 2004). The data were obtained through the analysis of hospital files. Statistical analysis was carried out with Fisher\'s exact test and the non-parametric Mann Whitney test. Results: Bacteria were identified in the cerebrospinal fluid (CSF) of 39% of the patients, with 50% of them being Gram-positive and 50%, Gram-negative. Most neonates presented unspecific signs and symptoms: fever (63.2%), irritability (31%), and lethargy (26.4%). The neurological findings occurred in 35.3% of the cases. Complications occurred in 48.2% of the neonates, and were mainly seizures (23%), intracranial hemorrhage (14.9%) and hydrocephalus (13.8%) with a mortality rate of 11.5%. At the comparison between clinical evolution and birth weight, associations between weight > or = 2,500g and seizures (p=0.047), weight > or = 2,500g and concave fontanel (p=0.019), bacteria in the CSF and complications (p=0.008) and bacteria in the CSF and death (p=0.043) were observed. Conclusions: The etiological agents most often identified in the CSF were enterobacteria (41%), followed by B Streptococcus (17.5%), non-B Streptococcus (17.5%), Staphylococcus aureus (11.7%), Neisseria meningitidis (8.8%) and Enterococcus faecalis (3.0%), with no statistical difference between the type of bacteria and birth weight. The predominant signs and symptoms were unspecific, with neurological findings in 35% of the cases. The higher frequency of neurological signs and symptoms in newborns with birth weight > or = 2,500g suggest a higher degree of central nervous system maturity in these infants. Although the mortality was lower than that observed in previous studies at the same Service, the frequency of complications was high, regardless of birth weight. The presence of bacteria in the CSF was associated to a higher frequency of seizures and mortality. The need for prolonged treatment in newborns with low birth weight suggests higher disease severity in this group of neonates.

The trace elements zinc and copper are essential components of many enzymes, some of which are of importance for the development and function of the central nervous system. Deficiency of the metals has been shown to lead to malformations and to the loss of myelin in animals. Earlier reports of zinc concentrations in the cerebrospinal fluid are few and the results variable. In multiple sclerosis and in epilepsy therapy with phenytoin there are varying reports of changes in serum concentrations of zinc and copper. A method was developed for the determination of zinc in cerebrospinal fluid by flame atomic absorption spectrophotometry utilizing a pulse nebulizer technique. Zinc and copper in serum were determined by flame atomic absorption spectrophotometry with conti nous aspiration. The normal concentrations of zinc in cerebrospi nal fluid was 0.16_+0.03 micromoles per litre (mean +_ S.D.). The zinc concentrations were correlated with protein and albumin concentrations in the cerebrospinal fluid but not with the serum zinc levels. In the patients with increased protein concentrations in the cerebrospinal fluid or with subarachnoid haemorrhage increased zinc levels were found. In 50 patients with multiple sclerosis lower serum concentrations of zinc were found compared to age and sex matched controls. In younger patients low serum levels of copper were also observed. There was no correlation between zinc and protein parameters in the cerebrospinal fluid of multiple sclerosis patients. In untreated epileptic males low serum zinc concentrations were observed. During the first 72 hours of phenytoin therapy increased serum concentrations of zinc and copper were found. during long-term therapy with phenytoin alone or in combination with other antiepileptic drugs there was an increased serum concentration of copper and ceruloplasmin but no change in zinc concentration compared with controls. / <p>Diss. Umeå, Umeå universitet, 1982, härtill 4 uppsatser</p> / digitalisering@umu

Although molybdenum blue solutions have been known for more than twocenturies, an understanding of their chemical nature is only beginning to emerge.This dissertation aimed at elucidating the structural nature of the polydisperse,nanoscopic components in the solution phases and the solid states of partiallyreduced polyoxomolybdate (Mo-POM). The study offered at least fourcontributions to the area: (1) a rational protocol for the molecular recognition ofMo-POM with de novo organic hosts. (2) demonstration of kinetic precipitation ofa dynamic mixture of polyoxomolybdates and application of the technique to thestudy of the dynamic mixture by TEM (3) characterization of the Mo-POMnanostructures by an unusual combination of complementary analyticaltechniques. (4) a general approach for the synthesis of crown-ethers-containingtripodal molecules.The molecular recognition of Mo-POM with designer tripodal hexaminetris-crown ethers opened a window to the solution phase structures of Mo-POMnanoscopic components. Studies with a series of structurally analogous hostsprobed the relationship between the structure of the molecular host and theformation of nanostructures.An unusual combination of complementary analytical protocols: flow fieldflowfractionation, electron microscopy (transmission and scanning), andinductively coupled plasma – emission spectroscopy, was used to monitor thesolution-phase evolution of Mo-POM nanostructures. The crystallization – drivenformation of keplerate Mo-POM and solution-phase evolution of structurallyrelated nanoscopic species were apparent in the self-assembling process ofpartially reduced Mo-POM.