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1.
Skin Health Dis ; 2(2): e95, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35677930

RESUMO

Background: Renal transplant recipients (RTRs) are at increased risk of keratinocyte cancer (KC), especially cutaneous squamous cell carcinoma (cSCC). Previous studies identified a genetic variant of the Methylenetetrahydrofolate Reductase (MTHFR) gene, C677T, which conferred a risk for diagnosis of cSCC in Irish RTRs. Objective: We sought to find further genetic variation in MTHFR and overlap genes that may be associated with a diagnosis of KC in RTRs. Methods: Genotyping of a combined RTR population (n = 821) from two centres, Ireland (n = 546) and the USA (n = 275), was performed. This included 290 RTRs with KC and 444 without. Eleven single nucleotide polymorphisms (SNPs) in the MTHFR gene and seven in the overlap gene MTHFR Chloride transport protein 6 (CLCN6) were evaluated and association explored by time to event analysis (from transplant to first KC) using Cox proportional hazards model. Results: Polymorphism at MTHFR CLCN6 (rs9651118) was significantly associated with KC in RTRs (HR 1.50, 95% CI 1.17-1.91, p < 0.00061) and cSCC (HR 1.63, 95% CI 1.14-2.34, p = 0.007). A separate SNP, MTHFR C677T, was also significantly associated with KC in the Irish population (HR 1.31, 95% CI 1.05-1.63, p = 0.016), but not American RTRs. Conclusions: We report the association of a SNP in the MTHFR overlap gene, CLCN6 and KC in a combined RTR population. While the exact function of CLCN6 is not known, it is proposed to be involved in folate availability. Future applications could include incorporation in a polygenic risk score for KC in RTRs to help identify those at increased risk beyond traditional risk factor assessment.

4.
Clin Exp Dermatol ; 45(7): 880-883, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32359186

RESUMO

Psoriasis often first presents in young adulthood, with the average age of diagnosis in women being 28 years, thus in the prime reproductive years. In addition, approximately 50% of pregnancies worldwide are unplanned. Although biologic therapies have revolutionized the treatment of moderate-to-severe psoriasis, there are no controlled studies of biologics in pregnant women. The increasing use of these agents in women of childbearing age highlights the need to further assess their safety during pregnancy. Postmarketing experience regarding the safety of these drugs is accumulating and being published, with largely reassuring results. We present our real-world experience of 17 pregnancies occurring in women on treatment with biologic agents for dermatological conditions to further add to the body of knowledge.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Fatores Biológicos/uso terapêutico , Gravidez/efeitos dos fármacos , Psoríase/tratamento farmacológico , Dermatopatias/tratamento farmacológico , Adulto , Anticorpos Monoclonais/uso terapêutico , Fatores Biológicos/efeitos adversos , Anticoncepção/normas , Feminino , Humanos , Terapia de Imunossupressão/efeitos adversos , Recém-Nascido , Troca Materno-Fetal/imunologia , Complicações na Gravidez/induzido quimicamente , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Terceiro Trimestre da Gravidez , Estudos Retrospectivos , Segurança , Adulto Jovem
7.
Diabet Med ; 36(1): 52-61, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30343489

RESUMO

AIMS: To evaluate the effectiveness of automated symptom and side effect monitoring on quality of life among individuals with symptomatic diabetic peripheral neuropathy. METHODS: We conducted a pragmatic, cluster randomized controlled trial (July 2014 to July 2016) within a large healthcare system. We randomized 1834 primary care physicians and prospectively recruited from their lists 1270 individuals with neuropathy who were newly prescribed medications for their symptoms. Intervention participants received automated telephone-based symptom and side effect monitoring with physician feedback over 6 months. The control group received usual care plus three non-interactive diabetes educational calls. Our primary outcomes were quality of life (EQ-5D) and select symptoms (e.g. pain) measured 4-8 weeks after starting medication and again 8 months after baseline. Process outcomes included receiving a clinically effective dose and communication between individuals with neuropathy and their primary care provider over 12 months. Interviewers collecting outcome data were blinded to intervention assignment. RESULTS: Some 1252 participants completed the baseline measures [mean age (sd): 67 (11.7), 53% female, 57% white, 8% Asian, 13% black, 20% Hispanic]. In total, 1179 participants (93%) completed follow-up (619 control, 560 intervention). Quality of life scores (intervention: 0.658 ± 0.094; control: 0.653 ± 0.092) and symptom severity were similar at baseline. The intervention had no effect on primary [EQ-5D: -0.002 (95% CI -0.01, 0.01), P = 0.623; pain: 0.295 (-0.75, 1.34), P = 0.579; sleep disruption: 0.342 (-0.18, 0.86), P = 0.196; lower extremity functioning: -0.079 (-1.27, 1.11), P = 0.896; depression: -0.462 (-1.24, 0.32); P = 0.247] or process outcomes. CONCLUSIONS: Automated telephone monitoring and feedback alone were not effective at improving quality of life or symptoms for people with symptomatic diabetic peripheral neuropathy. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02056431).


Assuntos
Neuropatias Diabéticas/terapia , Monitorização Fisiológica/métodos , Atenção Primária à Saúde , Qualidade de Vida , Idoso , Análise por Conglomerados , Neuropatias Diabéticas/fisiopatologia , Neuropatias Diabéticas/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Padrões de Prática Médica
8.
Clin Exp Dermatol ; 43(5): 577-578, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29464730

RESUMO

Anti-tumour necrosis factor (anti-TNF) therapies have been associated with neurological complications, including in rare cases demyelinating disease. It is currently unknown whether patients who have received more than one immunosuppressive agent or anti-TNF have a greater risk of demyelination. We report the case of a 37-year-old woman with psoriasis who presented with an acute episode of demyelination while on anti-TNF therapy. This case was complicated by the fact that progressive multifocal leukoencephalopathy was considered the likely diagnosis initially and was only definitively excluded by brain biopsy. This case demonstrates the difficulty establishing the correct diagnosis in patients with atypical presentations on immunomodulating therapies. We present this rare case of demyelination in a patient who received multiple immunosuppressive therapies to highlight this challenging clinical situation and discuss management with a literature review.


Assuntos
Adalimumab/efeitos adversos , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/diagnóstico , Imunossupressores/efeitos adversos , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Psoríase/tratamento farmacológico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Fator de Necrose Tumoral alfa/antagonistas & inibidores
9.
J Phys Chem A ; 117(36): 8671-9, 2013 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-23901786

RESUMO

The electronic structure and vibronic coupling in two similar molecular systems, radical C3H3 and anion C3H3(-), in ground and excited states, are investigated in detail to show how their equilibrium structures, in deviation from the Born-Oppenheimer approximation, originate from the vibronic mixing of at least two electronic states, producing the Jahn-Teller (JT), pseudo JT (PJT), and hidden PJT effects. Starting with the high-symmetry geometry D3h of C3H3, we evaluated its 2-fold degenerate ground electronic state (2)E″ and two lowest excited states (2)A1' and (2)E' and found that all of them contribute to the distortion of the ground state via the JT vibronic coupling problem E″ ⊗ e' and two PJT problems (E″ + A1') ⊗ e″ and (E″ + E') ⊗ (a2″ + e″); all the three active normal modes e'(1335 cm(-1)), e″(1030 cm(-1)), and a2″(778 cm(-1)) are imaginary, meaning that all the three vibronic couplings are sufficiently strong to cause instability, albeit in different directions. The first of them, the ground state JT effect, enhances one of the C-C bonds (toward an ethylenic form with C2v symmetry), while the two PJT effects produce, respectively, cis (a2″ toward C3v symmetry) and trans (e″) puckering of the hydrogen atoms. As a result, C3H3 has two coexisting equilibrium configurations with different geometry. In the C3H3(-) anion, the ground electronic state in D3h symmetry is an orbitally nondegenerate spin triplet (3)A2' with a group of close in energy singlet and triplet excited states in the order of (1)A1', (3)A1″, (1)E″, (3)E″, and (1)E'. This shows that two PJT couplings, ((3)A2' + (3)A1″) ⊗ a2″ and ((3)A2' + (3)E″) ⊗ e″, may influence the geometry of the equilibrium structure in the (3)A2' state. Indeed, both vibrational modes, a2″(1034 cm(-1)) and e″(1284 cm(-1)), are imaginary in this state. Similar to the radical case, they produce, respectively, cis (a2″) and trans (e″) puckering of the hydrogen atoms, but no e' distortion of the basic C3 triangle; the equilibrium configuration with Cs symmetry occurs along the stronger e″ distortions. Another higher-in-energy triplet-state minimum with C2v symmetry emerges as a result of a strong JTE in the excited (3)E″ electronic state. In addition to these APES minima with spin-triplet electronic states, the system has a coexisting minimum with a spin-singlet electronic state, which is shown to be due to the hidden PJT effect that couples two singlet excited states. The two lowest equilibrium configurations of the C3H3(-) anion with different geometry and spin realize a (common to all electronic e(2) configurations) magnetic and structural bistability accompanied by a spin crossover. Some general spectroscopic consequences are also noted. As a whole, this article is intended to demonstrate the efficiency of the vibronic coupling approach in rationalizing the origin of complicated structural features of molecular systems as due to a combination of nonadiabatic JT effects.

10.
Neuroscience ; 235: 187-99, 2013 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-23337538

RESUMO

Dramatic changes in the cytoskeleton and the morphology of oligodendrocytes (OLs) occur during various stages of the myelination process. OLs in culture produce large membrane sheets containing cytoskeletal veins of microtubules and actin filaments. We recently showed that estrogen receptors (ER) related to ERα/ß were expressed in the membrane sheets of mature OLs in culture. Ligation of these or other membrane ERs in OLs with both 17ß- and 17α-estradiol mediated rapid non-genomic signaling. Here, we show that estrogens also mediate rapid non-genomic remodeling of the cytoskeleton in mature OLs in culture. 17ß-Estradiol caused a rapid loss of microtubules and the actin cytoskeleton in the OL membrane sheets. It also increased phosphorylation of the actin filament-severing protein cofilin, thus inactivating it. Staining for actin barbed ends with rhodamine-actin showed that it decreased the amount of actin barbed ends. 17α-Estradiol, on the other hand, increased the percentage of cells with abundant staining of actin filaments and actin barbed ends, suggesting that it stabilized and/or increased the dynamics of the actin cytoskeleton. The specific ERα and ERß agonists, 4,4',4″-(4-propyl-(1H)-pyrazole-1,3,5-triyl) trisphenol (PPT) and diarylpropionitrile 2,3-bis(4-hydroxy-phenyl)-propionitrile (DPN), respectively, also caused the rapid phosphorylation of cofilin. Estrogen-induced phosphorylation of cofilin was inhibited by Y-27632, a specific inhibitor of the Rho-associated protein serine/threonine kinase (ROCK). The Rho/ROCK/cofilin pathway is therefore implicated in actin rearrangement via estrogen ligation of membrane ERs, which may include forms of ERα and ERß. These results indicate a role for estrogens in modulation of the cytoskeleton in mature OLs, and thus in various processes required for myelinogenesis.


Assuntos
Citoesqueleto/efeitos dos fármacos , Estradiol/farmacologia , Oligodendroglia/efeitos dos fármacos , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Animais , Animais Recém-Nascidos , Western Blotting , Células Cultivadas , Densitometria , Eletroforese em Gel de Poliacrilamida , Feminino , Imunofluorescência , Indicadores e Reagentes , Masculino , Microscopia Confocal , Bainha de Mielina/metabolismo , Oligodendroglia/ultraestrutura , Fosforilação , Ratos , Ratos Wistar , Receptores de Estrogênio/agonistas , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos
11.
Biophys J ; 100(6): 1490-8, 2011 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-21402031

RESUMO

Monolayers based on the composition of the cytoplasmic (CYT) or extracellular (EXT) sides of the myelin bilayer form coexisting immiscible liquid phases similar to the liquid-ordered/liquid-disordered phases in phospholipid/cholesterol monolayers. Increasing the temperature or surface pressure causes the two liquid phases to mix, although in significantly different fashion for the CYT and EXT monolayers. The cerebroside-rich EXT monolayer is near a critical composition and the domains undergo coalescence and a circle-to-stripe transition along with significant roughening of the domain boundaries before mixing. The phase transition in the cerebroside-free cytoplasmic side occurs abruptly without domain coalescence; hence, the cytoplasmic monolayer is not near a critical composition, although the domains exhibit shape instabilities within 1-2 mN/m of the transition. The change in mixing pressure decreases significantly with temperature for the EXT monolayer, with dΠ(crit)/dT ∼ 1.5 mN/m/°C, but the mixing pressure of the CYT monolayer varies little with temperature. This is due to the differences in the nonideality of cholesterol interactions with cerebrosides (EXT) relative to phospholipids (CYT). EXT monolayers based on the composition of white matter from marmosets with experimental allergic encephalomyelitis (EAE), an animal model of multiple sclerosis, remain phase-separated at higher surface pressures than control, while EAE CYT monolayers are similar to control. Myelin basic protein, when added to the CYT monolayer, increases lipid miscibility in CYT monolayers; likely done by altering the dipole density difference between the two phases.


Assuntos
Citoplasma/química , Espaço Extracelular/química , Lipídeos de Membrana/química , Bainha de Mielina/química , Animais , Cerebrosídeos/metabolismo , Citoplasma/metabolismo , Espaço Extracelular/metabolismo , Lipídeos de Membrana/metabolismo , Proteína Básica da Mielina/metabolismo , Bainha de Mielina/metabolismo , Pressão , Ratos , Temperatura
12.
Neurology ; 69(21): 2020-7, 2007 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-17928576

RESUMO

BACKGROUND: Providers are increasingly being held accountable for the quality of care provided. While quality indicators have been used to benchmark the quality of care for a number of other disease states, no such measures are available for evaluating the quality of care provided to adults with epilepsy. In order to assess and improve quality of care, it is critical to develop valid quality indicators. Our objective is to describe the development of quality indicators for evaluating care of adults with epilepsy. As most care is provided in primary and general neurology care, we focused our assessment of quality on care within primary care and general neurology clinics. METHODS: We reviewed existing national clinical guidelines and systematic reviews of the literature to develop an initial list of quality indicators; supplemented the list with indicators derived from patient focus groups; and convened a 10-member expert panel to rate the appropriateness, reliability, and necessity of each quality indicator. RESULTS: From the original 37 evidence-based and 10 patient-based quality indicators, the panel identified 24 evidence-based and 5 patient-based indicators as appropriate indicators of quality. Of these, the panel identified 9 that were not necessary for high quality care. CONCLUSION: There is, at best, a poor understanding of the quality of care provided for adults with epilepsy. These indicators, developed based on published evidence, expert opinion, and patient perceptions, provide a basis to assess and improve the quality of care for this population.


Assuntos
Atenção à Saúde/métodos , Atenção à Saúde/normas , Epilepsia/diagnóstico , Epilepsia/terapia , Garantia da Qualidade dos Cuidados de Saúde/métodos , Garantia da Qualidade dos Cuidados de Saúde/normas , Terminologia como Assunto , Humanos , Internacionalidade
13.
Cell Mol Life Sci ; 63(17): 1945-61, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16794783

RESUMO

Myelin basic protein (MBP), the second most abundant protein in central nervous system myelin, is responsible for adhesion of the cytosolic surfaces of multilayered compact myelin. A member of the 'intrinsically disordered' or conformationally adaptable protein family, it also appears to have several other functions. It can interact with a number of polyanionic proteins including actin, tubulin, Ca(2+)-calmodulin, and clathrin, and negatively charged lipids, and acquires structure on binding to them. It may act as a membrane actin-binding protein, which might allow it to participate in transmission of extracellular signals to the cytoskeleton in oligodendrocytes and tight junctions in myelin. Some size isoforms of MBP are transported into the nucleus and thus they may also bind polynucleotides. Extracellular signals received by myelin or cultured oligodendrocytes cause changes in phosphorylation of MBP, suggesting that MBP is also involved in signaling. Further study of this very abundant protein will reveal how it is utilized by the oligodendrocyte and myelin for different purposes.


Assuntos
Lipídeos de Membrana/metabolismo , Proteína Básica da Mielina/metabolismo , Oligodendroglia/fisiologia , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Animais , Proteínas do Citoesqueleto/metabolismo , Humanos , Lipídeos/química , Lipídeos de Membrana/química , Camundongos , Modelos Biológicos , Dados de Sequência Molecular , Proteína Básica da Mielina/genética , Fosforilação , Polieletrólitos , Polímeros/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
14.
J Pept Res ; 65(6): 529-37, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15885112

RESUMO

Protein farnesyltransferase (PFTase) catalyzes the attachment of a geranylazide (C10) or farnesylazide (C15) moiety from the corresponding prenyldiphosphates to a model peptide substrate, N-dansyl-Gly-Cys-Val-Ile-Ala-OH. The rates of incorporation for these two substrate analogs are comparable and approximately twofold lower than that using the natural substrate farnesyl diphosphate (FPP). Reaction of N-dansyl-Gly-Cys(S-farnesylazide)-Val-Ile-Ala-OH with 2-diphenylphosphanylbenzoic acid methyl ester then gives a stable alkoxy-imidate linked product. This result suggests future generations whereby azide groups introduced using this enzymatic approach are functionalized using a broad range of azide-reactive reagents. Thus, chemistry has been developed that could be used to achieve highly specific peptide and protein modification. The farnesylazide analog may be useful in certain biological studies, whereas the geranylazide group may be more useful for general protein modification and immobilization.


Assuntos
Alquil e Aril Transferases/metabolismo , Azidas/química , Peptídeos/síntese química , Difosfatos/síntese química
15.
Transplant Proc ; 37(1): 280-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15808619

RESUMO

BACKGROUND: Long-term storage of embryonic kidneys is crucial for the organization of transplantation and organ banking. In this study, we investigated the effects of controlled-rate freezing and ice-free vitrification on metanephroi (MN) viability. METHODS: Metanephroi isolated from 15-day (E15) timed pregnant Lewis rats were either: (i) frozen, using a DMSO/FCS/RPMI solution and a controlled freezing rate of -0.3 degrees C/min, from -10 degrees to -40 degrees C; or (ii) cryopreserved in an ice-free state by rapid cooling to -100 degrees C in cryoprotectant (VS55), followed by vitrification to -120 degrees C. After cryopreservation, the metanephroi were stored at -135 degrees C for 48 hours. After storage the MN were rewarmed, resuspended in culture media, and their viability was assessed using the AlamarBlue assay and histology (light microscopy, TEM, and cryosubstitution). RESULTS: There was statistically no difference in embryonic kidney metabolic activity of either of the cryopreserved MN groups relative to the control untreated group. However, cryosubstitution demonstrated the presence of significant ice formation during controlled-rate freezing, yet in contrast the amount of ice was significantly reduced by vitrification. This was confirmed by TEM, where vacuolation of the cytoplasm of controlled-rate frozen metanephroi was observed, whereas vitrified metanephroi had little cytoplasmic disruption. However, vitrified metanephroi showed mitochondrial and nuclear injury at the cellular level. CONCLUSIONS: There is a need for long-term storage of organs to make MN transplantation a reality. This study demonstrates that standard freezing methods are unsuitable for this purpose. Vitrification yielded more promising results, but further development is required.


Assuntos
Rim/citologia , Preservação de Órgãos/métodos , Animais , Sobrevivência Celular , Criopreservação/métodos , Feminino , Transplante de Tecido Fetal , Transplante de Rim , Gravidez , Ratos , Ratos Endogâmicos Lew
16.
Br J Pharmacol ; 143(5): 649-61, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15466448

RESUMO

1 1-[4-(3-piperidin-1-yl-propoxy)-benzyl]-piperidine (JNJ-5207852) is a novel, non-imidazole histamine H3 receptor antagonist, with high affinity at the rat (pKi=8.9) and human (pKi=9.24) H3 receptor. JNJ-5207852 is selective for the H3 receptor, with negligible binding to other receptors, transporters and ion channels at 1 microm. 2 JNJ-5207852 readily penetrates the brain tissue after subcutaneous (s.c.) administration, as determined by ex vivo autoradiography (ED50 of 0.13 mg kg(-1) in mice). In vitro autoradiography with 3H-JNJ-5207852 in mouse brain slices shows a binding pattern identical to that of 3H-R-alpha-methylhistamine, with high specific binding in the cortex, striatum and hypothalamus. No specific binding of 3H-JNJ-5207852 was observed in brains of H3 receptor knockout mice. 3 In mice and rats, JNJ-5207852 (1-10 mg kg(-1) s.c.) increases time spent awake and decreases REM sleep and slow-wave sleep, but fails to have an effect on wakefulness or sleep in H3 receptor knockout mice. No rebound hypersomnolence, as measured by slow-wave delta power, is observed. The wake-promoting effects of this H3 receptor antagonist are not associated with hypermotility. 4 A 4-week daily treatment of mice with JNJ-5207852 (10 mg kg(-1) i.p.) did not lead to a change in body weight, possibly due to the compound being a neutral antagonist at the H3 receptor. 5 JNJ-5207852 is extensively absorbed after oral administration and reaches high brain levels. 6 The data indicate that JNJ-5207852 is a novel, potent and selective H3 antagonist with good in vitro and in vivo efficacy, and confirm the wake-promoting effects of H3 receptor antagonists.


Assuntos
Antagonistas dos Receptores Histamínicos/farmacologia , Piperidinas/farmacologia , Receptores Histamínicos H3/efeitos dos fármacos , Vigília/efeitos dos fármacos , Administração Oral , Animais , Autorradiografia , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , AMP Cíclico/metabolismo , Eletrodos , Eletroencefalografia/efeitos dos fármacos , Eletromiografia/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos/administração & dosagem , Antagonistas dos Receptores Histamínicos/farmacocinética , Humanos , Injeções Intravenosas , Masculino , Camundongos , Camundongos Knockout , Camundongos Obesos , Atividade Motora/efeitos dos fármacos , Piperidinas/administração & dosagem , Piperidinas/farmacocinética , Polissonografia , Ratos , Ratos Sprague-Dawley , Receptores Histamínicos H3/genética , Sono/efeitos dos fármacos , Transdutores
17.
Neurology ; 60(6): 975-8, 2003 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-12654962

RESUMO

OBJECTIVE: To investigate the occurrence of status epilepticus and seizure clusters, and the duration until first seizure at epilepsy monitoring units in the United States. METHODS: The authors examined the inpatient video-EEG monitoring reports of 514 consecutive patients admitted to five comprehensive epilepsy centers during the year 2000. Time to first seizure, seizure clustering, and seizure duration were ascertained from reports and entered into a database. RESULTS: In 169 admissions with complex partial seizures (CPSs) or secondarily generalized tonic-clonic (2GTC) seizures, there were 5 (3.0%) patients with status epilepticus, 30 (17.8%) with 4-hour seizure clusters, and 82 (48.5%) with 24-hour seizure clusters. There were no statistically significant differences between centers, except that seizure clusters were observed to be less common at the one center with a formal drug withdrawal protocol. The average time to CPS or 2GTC seizure was 2.1 days; the average number of days to nonepileptic event was 1.2 days (p = 0.001). CONCLUSIONS: Although status epilepticus is uncommon at epilepsy monitoring units, clusters of seizures are common. Intensive monitoring with drug withdrawal must be performed in a highly supervised, hospitalized setting. Inpatient video-EEG monitoring is efficient, with recording of the first epileptic or nonepileptic events in 2 days or less.


Assuntos
Eletroencefalografia , Epilepsia/fisiopatologia , Monitorização Fisiológica , Convulsões/epidemiologia , Estado Epiléptico/epidemiologia , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/uso terapêutico , Estudos de Coortes , Eletrocardiografia , Eletroencefalografia/métodos , Eletroculografia , Epilepsia/complicações , Feminino , Humanos , Incidência , Pacientes Internados , Tempo de Internação , Masculino , Monitorização Fisiológica/métodos , Estudos Retrospectivos , Convulsões/etiologia , Estado Epiléptico/etiologia , Síndrome de Abstinência a Substâncias/epidemiologia , Síndrome de Abstinência a Substâncias/etiologia , Gravação em Vídeo
18.
J Neurosci Res ; 66(2): 242-53, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11592120

RESUMO

Oligodendrocytes (OLs) and the myelin produced by them are enriched in two glycosphingolipids, galactosylceramide (GalC) and its sulfated form, cerebroside sulfate (CBS). We showed earlier that these two glycolipids in opposed liposomal membranes or in methanol solution can adhere to each other. Here we have examined the potential effect of an interaction between GalC/CBS in apposed membranes of oligodendrocytes (OLs) by incubating cultured OLs with GalC/CBS-containing liposomes and observing the effect on the membrane sheets produced by OLs and on the distribution of OL constituents using fluorescent antibodies and confocal microscopy. The GalC/CBS-containing liposomes caused redistribution or a decrease in the density of anti-GalC and anti-MBP staining but had no effect on the density or distribution of staining by anti-PI(4,5)P(2) that remained uniformly distributed in the membrane sheets. There was no apparent change in the area of the membrane sheets nor in the amount of MBP in OL membranes, as determined by slot blots. In addition, the GalC/CBS-containing liposomes caused depolymerization of microtubules and actin filaments suggesting that the interaction of GSL-containing liposomes with the extracellular surface of the OL caused transmission of a signal across the membrane. Because these two glycolipids can adhere to each other across apposed membranes, the liposomal glycolipids may be interacting with a GalC/CBS-enriched signaling domain in the OL plasma membrane.


Assuntos
Cerebrosídeos/administração & dosagem , Citoesqueleto/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Animais , Biopolímeros , Bovinos , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/ultraestrutura , Cerebrosídeos/farmacologia , Citoesqueleto/ultraestrutura , Galactosilceramidas/administração & dosagem , Galactosilceramidas/farmacologia , Lipossomos , Lipídeos de Membrana/metabolismo , Camundongos , Microscopia Confocal , Microscopia de Fluorescência , Proteína Básica da Mielina/análise , Bainha de Mielina/metabolismo , Oligodendroglia/ultraestrutura , Fosfatidilinositóis/análise , Fosfolipídeos/química , Ratos , Ratos Wistar , Transdução de Sinais , Medula Espinal/citologia
19.
Ground Water ; 39(4): 534-45, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11447854

RESUMO

Results are presented for numerical simulations of ground water flow and physical transport associated with a natural gradient tracer experiment conducted within a heterogeneous alluvial aquifer of the Natural Attenuation Study (NATS) site near Columbus, Mississippi. A principal goal of NATS is to evaluate biogeochemical models that predict the rate and extent of natural biodegradation under field conditions. This paper describes the initial phase in the model evaluation process, i.e., calibration of flow and physical transport models that simulate conservative bromide tracer plume evolution during NATS. An initial large-scale flow model (LSM) is developed encompassing the experimental site and surrounding region. This model is subsequently scaled down in telescopic fashion to an intermediate-scale ground water flow model (ISM) covering the tracer-monitoring network, followed by a small-scale transport model (SSM) focused on the small region of hydrocarbon plume migration observed during NATS. The LSM uses inferred depositional features of the site in conjunction with hydraulic conductivity (K) data from aquifer tests and borehole flowmeter tests to establish large-scale K and flow field trends in and around the experimental site. The subsequent ISM incorporates specified flux boundary conditions and large-scale K trends obtained from the calibrated LSM, while preserving small-scale K structure based on some 4000 flowmeter data for solute transport modeling. The configuration of the ISM-predicted potentiometric surface approximates that of the observed surface within a root mean squared error of 0.15 m. The SSM is based on the dual-domain mass-transfer approach. Despite the well-recognized difficulties in modeling solute transport in extremely heterogeneous media as found at the NATS site, the dual-domain model adequately reproduced the observed bromide concentration distributions. Differences in observed and predicted bromide concentration distributions are attributed to aquifer heterogeneity at the decimeter (dm) and smaller scales. The calibrated transport parameters for the SSM (i.e., 1:7 for the ratio of mobile-to-total porosity; 2.5 x 10(-3) day-1 for the mass-transfer coefficient; 1 m for longitudinal dispersivity; and 0.1 m for transverse dispersivity) are consistent with separate numerical simulations of two earlier tracer experiments at the site. The multiscale modeling approach adopted in this study permits the incorporation of both large-scale geologic features important for flow simulation and small-scale heterogeneities critical for transport simulation. In addition, the dual-domain transport model provides a foundation for multispecies reactive transport modeling studies of natural attenuation of hydrocarbons during NATS.


Assuntos
Hidrocarbonetos/análise , Modelos Teóricos , Solo , Abastecimento de Água , Fenômenos Químicos , Físico-Química , Monitoramento Ambiental , Previsões , Fenômenos Geológicos , Geologia , Movimentos da Água
20.
Biochim Biophys Acta ; 1511(1): 28-41, 2001 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-11248202

RESUMO

Magainins and other antimicrobial peptides increase ion flux across the membrane. They may do this by forming some type of pore or by perturbing lipid organization due to peptide lying on the bilayer surface. In order to determine if magainins perturb the lipid sufficiently to permeabilize the bilayer, their effect on the motion of fatty acid and lipid spin labels in phosphatidylcholine/phosphatidylglycerol (PC/PG) lipid vesicles was determined. Their effect was compared to two synthetic peptides, 18L and Ac-18A-NH(2), designed to mimic the naturally occurring classes of lytic (class L) and apolipoprotein (class A) amphipathic helices, respectively. We show that although magainins and 18L both had significant effects on lipid chain order, much greater than Ac-18A-NH(2), there was no correlation between these effects and the relative ability of these three peptide classes to permeabilize PC/PG vesicles in the order magainins=Ac-18A-NH(2) >> 18L. This suggests that the perturbing effects of magainins on lipid chain order at permeabilizing concentrations are not directly responsible for the increased leakage of vesicle contents. The greater ability of the magainins to permeabilize PC/PG vesicles relative to 18L is thus more likely due to formation of some type of pore by magainins. The greater ability of Ac-18A-NH(2) relative to 18L to permeabilize PC/PG vesicles despite its lack of disordering effect must be due to its ability to cause membrane fragmentation. Effects of these peptides on other lipids indicated that the mechanism by which they permeabilize lipid bilayers depends both on the peptide and on the lipid composition of the vesicles.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Ácidos Graxos/química , Bicamadas Lipídicas/química , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/síntese química , Espectroscopia de Ressonância de Spin Eletrônica , Dados de Sequência Molecular , Permeabilidade , Marcadores de Spin , Relação Estrutura-Atividade
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