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1.
Nat Neurosci ; 25(2): 226-237, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35115730

RESUMO

Answer ALS is a biological and clinical resource of patient-derived, induced pluripotent stem (iPS) cell lines, multi-omic data derived from iPS neurons and longitudinal clinical and smartphone data from over 1,000 patients with ALS. This resource provides population-level biological and clinical data that may be employed to identify clinical-molecular-biochemical subtypes of amyotrophic lateral sclerosis (ALS). A unique smartphone-based system was employed to collect deep clinical data, including fine motor activity, speech, breathing and linguistics/cognition. The iPS spinal neurons were blood derived from each patient and these cells underwent multi-omic analytics including whole-genome sequencing, RNA transcriptomics, ATAC-sequencing and proteomics. The intent of these data is for the generation of integrated clinical and biological signatures using bioinformatics, statistics and computational biology to establish patterns that may lead to a better understanding of the underlying mechanisms of disease, including subgroup identification. A web portal for open-source sharing of all data was developed for widespread community-based data analytics.


Assuntos
Esclerose Lateral Amiotrófica , Células-Tronco Pluripotentes Induzidas , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Linhagem Celular , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios Motores/fisiologia
2.
J Child Orthop ; 13(4): 423-430, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31489050

RESUMO

PURPOSE: The aim of the study was to evaluate the accuracy and radiographic outcomes of Canale's method in patients with idiopathic leg-length discrepancy (LLD) following percutaneous epiphysiodesis. The accuracy of two common growth prediction methods was assessed. METHODS: A total of 18 patients with 26 affected bones (eight distal femur, two proximal tibia, five combined) were clinically and radiologically analyzed after reaching skeletal maturity. We compared the final effect of epiphysiodesis at maturity with the expected effect of epiphysiodesis before surgery; these measures were calculated using the Green-Anderson and multiplier methods, respectively. We furthermore compared pre- and postoperative frontal and lateral plane radiographs. RESULTS: The average LLD was 21.2 mm before surgery and 7.9 mm after epiphysiodesis. The final effect of both methods was not significantly different compared with the expected effect of epiphysiodesis before surgery. However, the prediction by the Green-Anderson method was closer to the definitive epiphysiodesis effect. The frontal plane radiographic deformity parameters did not change significantly after epiphysiodesis. The postoperative sagittal plane radiographic deformity parameters were in the normal range. CONCLUSION: The Canale technique is a reliable method to reduce LLD in children. With regards to growth prediction, the Green-Anderson method using bone age seems to be more accurate than the multiplier method using chronological age. However, a relative over-estimation was observed with both methods in several cases, which might result in an insufficient correction. LEVEL OF EVIDENCE: IV, Therapeutic study.

4.
J Nutr Health Aging ; 22(9): 1045-1050, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30379301

RESUMO

OBJECTIVES: There is debate surrounding the adequacy of total and free 25 hydroxy vitamin D [25(OH)D] levels in black Americans who have inherently high bone mineral density [BMD] and low serum concentration of vitamin D binding proteins [VDBP]. DESIGN: Retrospective analysis of serum samples and BMD analyses from the African American Health Study [AAHS] cohort. SETTING: The AAHS is a population-based longitudinal study initiated to examine issues of disability and frailty among urban-dwelling black Americans in the city of Saint Louis, Missouri. PARTICIPANTS: 122 men and 206 women, age 60.2 ± 4.3 years. INTERVENTION: Retrospective analysis. MEASUREMENTS: Total 25(OH)D, VDBP, PTH, and BMD of the lumbar spine and hip by dual energy x-ray photometry (DXA). Free and bioavailable vitamin D levels were calculated using serum concentrations and affinity constants for the VDBP (Gc1F and Gc1S) phenotypes. RESULTS: Serum total 25(OH)D levels were 14.6 ± 8.9 ng/mL (36 ± 22 nmol/L). Vitamin D insufficiency was estimated by compensatory elevations of PTH above the normal range (> 65 pg/mL). PTH levels were within the normal reference range in > 95% of the samples at total 25(OH)D levels ≥ 20 ng/mL (≥50 nmol/L). There was no difference in the correlation of the reciprocal relationship of vitamin D vs parathyroid hormone between the VDBP phenotypes. Receiver operating characteristic curve analyses indicated that serum total 25(OH)D discriminated sufficiency from insufficiency at least as well as the calculated levels of the free and bioavailable vitamin D. Very low levels of total 25(OH)D (≤ 8 ng/mL, ≤20 nmol/L) were associated with decreased BMD (p=0.02), but higher levels of 25(OH)D did not show statistical differences in BMD. CONCLUSION: Total 25(OH)D levels of ≤ 8ng/mL (≤20 nmol/L) are associated with clinically significant changes in BMD, whereas total 25(OH)D levels ≥ 20 ng/mL (≥50 nmol/L) suppressed PTH and were not associated with deficiencies in BMD. Lower levels of 25(OH)D may be acceptable for bone health in black than in white Americans.


Assuntos
Densidade Óssea/efeitos dos fármacos , Hormônio Paratireóideo/deficiência , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Negro ou Afro-Americano , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Estudos Retrospectivos , Estados Unidos , Vitamina D/metabolismo
5.
J Child Orthop ; 12(6): 558-565, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30607202

RESUMO

Peromelia or congenital transverse deficiency describes a truncation of the upper limb below various limb levels. Recommendations regarding treatment vary and are mainly based on expert opinions. This paper summarizes the current literature regarding the aetiology, pathogenesis and specifically treatment algorithms for children with peromelia. We performed a non-systematic review of the current literature from MEDLINE/PubMed to obtain comprehensive up-to-date information about peromelia, focusing on current recommendations for the treatment of peromelia (e.g. prosthetic fitting, external stump lengthening). The current literature lacks clear evidence as to whether prosthetic treatment is superior to prosthetic non-usage. However, based on the available studies, children with transradial or transhumeral peromelia should preferably be fitted with passive/cosmetic prostheses at the age between six and 24 months, followed by active/myoelectric devices at the age of 2.5 to four years. It remains controversial whether early myoelectric prosthetic fitting can reduce prosthesis rejection times; however, cognitive readiness and the ability to absolve a guided training programme are seen as important prerequisites for myoelectric fitting. Children with very short stumps may benefit from stump lengthening using external fixators and prosthetic modification. The treatment of children with peromelia generally requires a guided, multidisciplinary team approach. A training programme is essential to optimize individuals' performance in the execution of activities of daily living and decrease rejection risks whenever a myoelectric device is prescribed. Myoelectric fitting should preferably be commenced at no later than four years of age. However, long-term reports on the benefits of prosthetic treatment are still pending.

6.
Int J Obes (Lond) ; 42(3): 391-397, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28990588

RESUMO

OBJECTIVE: Resistance at the brain receptors for leptin and insulin has been associated with increased feeding, obesity and cognitive impairments. The causal agent for central resistance is unknown but could be derived from the blood. Here we postulate whether hypertriglyceridemia, the major dyslipidemia of the metabolic syndrome, could underlie central leptin and insulin resistance. DESIGN: We used radioactively labeled triglycerides to measure blood-brain barrier (BBB) penetration, western blots to measure receptor activation, and feeding and cognitive tests to assess behavioral endpoints. RESULTS: Human CSF was determined to contain triglycerides, a finding previously unclear. The radioactive triglyceride triolein readily crossed the BBB and centrally administered triolein and peripherally administered lipids induced in vivo leptin and/or insulin resistance at hypothalamic receptors. Central triolein blocked the satiety effect of centrally administered leptin. Decreasing serum triglycerides with gemfibrozil improved both learning and memory inversely proportionate to triglyceride levels. CONCLUSIONS: Triglycerides cross the blood-brain barrier rapidly, are found in human cerebrospinal fluid, and induce central leptin and insulin receptor resistance, decreasing satiety and cognition.


Assuntos
Antígenos CD/metabolismo , Barreira Hematoencefálica/metabolismo , Resistência à Insulina/fisiologia , Leptina/metabolismo , Receptor de Insulina/metabolismo , Triglicerídeos/metabolismo , Idoso , Animais , Cognição/efeitos dos fármacos , Feminino , Genfibrozila/farmacologia , Humanos , Leptina/farmacologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Resposta de Saciedade/efeitos dos fármacos , Triglicerídeos/sangue , Triglicerídeos/líquido cefalorraquidiano , Trioleína/metabolismo , Trioleína/farmacologia
8.
Orthopade ; 43(11): 1016-21, 2014 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-25209017

RESUMO

BACKGROUND: The congenital tibia hemimelia, also called tibial deficiency, is a rare disorder with unknown cause, showing many associated abnormalities or varying syndromes. METHODS: The correct diagnosis can be easily established using radiographs and/or magnetic resonance imaging in the postpartum setting. However, treatment may be difficult and needs to take into consideration the given anatomic situation in the knee and ankle joint. CONCLUSION: Prosthetic fitting may be possible in mild cases. Nevertheless, the majority of patients need to undergo surgical reconstruction in order to restore a functional, mobile, and stable knee and ankle joint.


Assuntos
Ectromelia/diagnóstico por imagem , Ectromelia/cirurgia , Articulação do Joelho/anormalidades , Articulação do Joelho/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Tíbia/anormalidades , Tíbia/cirurgia , Humanos , Articulação do Joelho/diagnóstico por imagem , Osteotomia/métodos , Radiografia , Tíbia/diagnóstico por imagem
9.
J Hand Surg Eur Vol ; 39(7): 719-26, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24563498

RESUMO

The purpose of this systematic review was to determine the outcome of interphalangeal (IP) joint motion in children undergoing open surgical release, splinting, and passive exercising therapy for the treatment of paediatric trigger thumb. We conducted an online literature search of seven major databases. Only studies with a mean follow-up of at least 12 months were considered for inclusion. Seventeen retrospective studies and one prospective study met all the inclusion criteria. They reported on the results of surgery (634 children, 759 thumbs), splinting (115 children, 138 thumbs), and passive exercising (89 children, 108 thumbs). The mean follow-up periods were 59 (surgery), 23 (splinting), and 76 months (exercising), respectively. Full IP joint motion without residual triggering was achieved in 95% of all children undergoing surgery, in 67% of children treated with continuous splinting, and 55% after passive exercising. Based on the low level of evidence available, it seems that open surgery resulted in more reliable and rapid outcomes compared with nonoperative treatment.


Assuntos
Terapia por Exercício , Contenções , Dedo em Gatilho/cirurgia , Criança , Pré-Escolar , Articulações dos Dedos , Humanos , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Resultado do Tratamento , Dedo em Gatilho/fisiopatologia
10.
Toxicol In Vitro ; 27(6): 1693-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23665401

RESUMO

The effects of pseudomonal virulence factor pyocyanin, and LPS from Pseudomonas aeruginosa and Escherichia coli on urothelial mediator release and cytokine production were examined. RT4 urothelial cells were treated with pyocyanin (1-100 µM) or LPS (1-100 ng/mL) for 24-h. Effects were measured in terms of changes in cell viability, basal and stretch-induced acetylcholine (Ach) and PGE2 release, and inflammatory cytokines (IL-6 and IL-12) production. Twenty-four hour pyocyanin (100 µM) treatment significantly decreased urothelial cell viability, while stretch-induced Ach release response was inhibited. E. coli LPS (100 ng/mL) produced a similar response with an additional significant increase in basal Ach release. All three virulence factors significantly increased urothelial PGE2 release; under basal release for pyocyanin (100 µM), stretch-induced release for pseudomonal LPS (≥ 10 ng/mL) and both basal and stimulated release for E. coli LPS (≥ 10 ng/mL). IL-6 and IL-12 were not detected in control samples, however 24h treatment with pyocyanin (100 µM) or LPS (100 ng/mL) resulted in IL-6 release from urothelial cells. The changes in urothelial Ach and PGE2, and release of inflammatory cytokine IL-6 induced by exposure to the bacterial virulence factors may play a role in the symptoms of pain and urinary urgency experienced with urinary tract infections.


Assuntos
Células Epiteliais/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Piocianina/farmacologia , Urotélio/citologia , Acetilcolina/metabolismo , Linhagem Celular , Dinoprostona/metabolismo , Células Epiteliais/metabolismo , Humanos , Interleucina-12/metabolismo , Interleucina-6/metabolismo
12.
Curr Med Res Opin ; 29(7): 861-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23514092

RESUMO

Many efficacy endpoints have been used in clinical trials of acute migraine pharmacotherapy. Headache response or headache relief (i.e., moderate/severe pain reduced to mild/no pain) at a single, specified time-point, traditionally the primary endpoint, and headache recurrence (i.e., return of pain after initial postdose relief) are inadequate. Headache relief does not provide information about pain-free response and counts a partial response as a treatment success. Headache recurrence can reflect sustained efficacy but is confounded by initial response to treatment, because ineffective drugs have low recurrence rates. The International Headache Society (IHS) guidelines state that 2 hour pain-free response and sustained pain-free response (i.e., freedom from pain with no recurrence or use of rescue or study medication 2-24 hours postdose) provide the most clinically relevant information about the efficacy of migraine pharmacotherapy. The pain-free criterion counts partial responses as failures and thus is a more rigorous test of therapeutic benefit than headache relief, and the two endpoints together incorporate the main treatment attributes that determine patient satisfaction. As an example, consider needle-free subcutaneous sumatriptan and oral triptan tablets. An open-label study of needle-free subcutaneous sumatriptan by Cady and colleagues found that 2 hour pain-free response and sustained pain-free response were 64% and 42% respectively. For oral triptan tablets, the 2001 metaanalysis by Ferrari and colleagues reported 2 hour pain-free response rates ranging from 23% to 38% and sustained pain-free response rates ranging from 11% to 26%. The measures of pain-free response 2 hours postdose and sustained pain-free response can differentiate among treatments and be used to guide therapeutic choices.


Assuntos
Transtornos de Enxaqueca/tratamento farmacológico , Manejo da Dor , Medição da Dor , Agonistas do Receptor 5-HT1 de Serotonina/uso terapêutico , Sumatriptana/uso terapêutico , Humanos , Dor/tratamento farmacológico , Satisfação do Paciente , Projetos de Pesquisa , Sumatriptana/análogos & derivados , Resultado do Tratamento
13.
Orthopade ; 37(6): 532, 534-6, 538-40, 2008 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-18483720

RESUMO

The perfect time for hip screening is when every pathologically deformed hip can be diagnosed by sonography and after spontaneous resolution of immature, dysplastic hips. In addition, the beginning of therapy should be early enough to provide the best possible outcome concerning the anatomically correct healing of the patient's hip. Even though every child should be screened by sonography in the first few days of life, a reasonable way could be ultrasound screening in the first week for clinically unstable hips or newborns with risk factors such as breech position combined with ultrasound screening of every newborn between the fourth and sixth week.


Assuntos
Luxação Congênita de Quadril/diagnóstico por imagem , Triagem Neonatal , Análise Custo-Benefício , Comparação Transcultural , Europa (Continente) , Luxação Congênita de Quadril/economia , Luxação Congênita de Quadril/cirurgia , Humanos , Lactente , Recém-Nascido , Triagem Neonatal/economia , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Quadril/economia , Osteoartrite do Quadril/prevenção & controle , Radiografia , Ultrassonografia
14.
Adv Drug Deliv Rev ; 59(6): 444-53, 2007 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-17582648

RESUMO

The aims of the current work included: development of a new production method for nanoparticles of water-insoluble drugs in combination with lipids, characterization of the nanoparticles and development of lipid nanosuspension formulations, and investigation of the feasibility of delivering the nanosuspensions as aerosols for inhalation using Aradigm's AERx Single Dose Platform (SDP) with micron-sized nozzles and the all mechanical AERx Essence with sub-micron-sized nozzles. The continuous SFEE method was used for particle precipitation of solid lipid nanoparticles (SLN). The method allowed for production of stable particulate aqueous suspensions of a narrow size distribution, with a volume mean diameter below 30 nm (D99% cumulative volume below 100 nm). Thus the particle size obtained was significantly smaller than previously has been achieved by other techniques. The residual solvent content in the final suspension was consistently below 20 ppm. Drug loading values between 10-20% w/w drug were obtained for model compounds ketoprofen and indomethacin in formulation with lipids such as tripalmitin, tristearin and Gelucire 50/13. It was observed that the loading capacity achieved was higher than the thermodynamic limit of the solubility of the drugs in molten lipids. Lipid nanosuspension formulations were successfully aerosolized using both of the AERx systems. As measured by both cascade impactor and laser diffraction, the aerosol fine particle fraction (FPF) was comparable to drug solution formulations typically used in these devices; i.e., greater than 90% of the aerosol mass resided in particles less than 3.5 mum aerodynamic diameter.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/química , Administração por Inalação , Aerossóis , Cromatografia com Fluido Supercrítico , Formas de Dosagem , Estabilidade de Medicamentos , Emulsões , Indometacina/administração & dosagem , Indometacina/química , Cetoprofeno/administração & dosagem , Cetoprofeno/química , Lipídeos/administração & dosagem , Lipídeos/química , Nanopartículas/administração & dosagem , Tamanho da Partícula , Solubilidade , Suspensões
15.
Neurobiol Aging ; 28(8): 1170-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16846666

RESUMO

Accumulation of toxic amyloid-beta (Abeta)-peptide is suggested to cause oxidative stress in Alzheimer's disease (AD) brain, and decrease the content of polyunsaturated fatty acids (PUFA) in neuronal membrane lipids. The senescence accelerated prone mice (SAMP8) have age-related increases in the level of hippocampal Abeta-peptide, learning and memory deficits, and a shorter lifespan than their controls. The effects of age-related oxidative damage on PUFA content in membrane phospholipids (PL), and alpha-tocopherol concentration were investigated in hippocampus and amygdala of 2-, 4-, 12-, and 18-month-old SAMP8 mice. In comparison to the younger SAMP8 mice, the hippocampus of the 12-month-old mice contained lower proportions of docosahexaenoic acid (DHA) in phosphatidylserine (PS) and phosphatidylinositol (PI), and higher proportions of arachidonic acid (AA) in PS. Their amygdala contained a lower proportion of AA in phosphatidylcholine (PC). In the hippocampus of the oldest age group, the proportions of DHA in PS, and AA in PC and PI were higher than in the younger age groups. At 2 months of age, the amygdala contained a higher concentration of alpha-tocopherol than the hippocampus, but this difference between the two brain regions was lost with aging. The oldest age group contained the highest concentration of alpha-tocopherol, indicating a protection against oxidative damage of PUFA in brain membrane phospholipids.


Assuntos
Envelhecimento/genética , Envelhecimento/metabolismo , Encéfalo/metabolismo , Peroxidação de Lipídeos , Fatores Etários , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Química Encefálica , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Mutantes Neurológicos , Oligodesoxirribonucleotídeos Antissenso/farmacologia , alfa-Tocoferol/metabolismo
16.
Am J Epidemiol ; 160(12): 1194-204, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15583372

RESUMO

Menstrual cycle characteristics may have implications for women's fecundability and risk of hormonally related diseases. Certain pesticides disrupt the estrous cycle in animals. The authors investigated the cross-sectional association between pesticide use and menstrual function among 3,103 women living on farms in Iowa and North Carolina. Women were aged 21-40 years, premenopausal, not pregnant or breastfeeding, and not taking oral contraceptives. At study enrollment (1993-1997), women completed two self-administered questionnaires on pesticide use and reproductive health. Exposures of interest were lifetime use of any pesticide and hormonally active pesticides. Menstrual cycle characteristics of interest included cycle length, missed periods, and intermenstrual bleeding. The authors used generalized estimating equations to assess the association between pesticide use and menstrual cycle characteristics, controlling for age, body mass index, and current smoking status. Women who used pesticides experienced longer menstrual cycles and increased odds of missed periods (odds ratio = 1.5, 95% confidence interval: 1.2, 1.9) compared with women who never used pesticides. Women who used probable hormonally active pesticides had a 60-100% increased odds of experiencing long cycles, missed periods, and intermenstrual bleeding compared with women who had never used pesticides. Associations remained after control for occupational physical activity.


Assuntos
Doenças dos Trabalhadores Agrícolas/induzido quimicamente , Distúrbios Menstruais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Praguicidas/intoxicação , Adulto , Estudos Transversais , Feminino , Humanos , Iowa , North Carolina , Pré-Menopausa , Características de Residência , Saúde da População Rural
17.
Neuroscience ; 126(4): 915-26, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15207326

RESUMO

The senescence-accelerated mouse (SAM) is a murine model of accelerated senescence that was established using phenotypic selection. The SAMP series includes nine substrains, each of which exhibits characteristic disorders. SAMP8 is known to exhibit age-dependent learning and memory deficits. In our previous study, we reported that brains from 12-month-old SAMP8 have greater protein oxidation, as well as lipid peroxidation, compared with brains from 4-month-old SAMP8 mice. In order to investigate the relation between age-associated oxidative stress on specific protein oxidation and age-related learning and memory deficits in SAMP8, we used proteomics to identify proteins that are expressed differently and/or modified oxidatively in aged SAMP8 brains. We report here that in 12 month SAMP8 mice brains the expressions of neurofilament triplet L protein, lactate dehydrogenase 2 (LDH-2), heat shock protein 86, and alpha-spectrin are significantly decreased, while the expression of triosephosphate isomerase (TPI) is increased compared with 4-month-old SAMP8 brains. We also report that the specific protein carbonyl levels of LDH-2, dihydropyrimidinase-like protein 2, alpha-spectrin and creatine kinase, are significantly increased in the brain of 12-month-old SAMP8 mice when compared with the 4-month-old SAMP8 brain. These findings are discussed in reference to the effect of specific protein oxidation and changes of expression on potential mechanisms of abnormal alterations in metabolism and neurochemicals, as well as to the learning and memory deficits in aged SAMP8 mice.


Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , Regulação da Expressão Gênica/fisiologia , Estresse Oxidativo/fisiologia , Proteínas/metabolismo , Envelhecimento/genética , Animais , Western Blotting/métodos , Eletroforese em Gel Bidimensional/métodos , Masculino , Espectrometria de Massas/métodos , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes Neurológicos , Proteômica/métodos
18.
Life Sci ; 69(23): 2789-99, 2001 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-11720083

RESUMO

Genetically obese (ob/ob) mice were employed for the study of the effect of metformin on activity and expression of nitric oxide synthase (NOS ) in vitro and in vivo. For in vitro analysis, mouse liver extracts were used. For the in vivo study, (ob/ob) and their control litter mates (ob/c) mice were injected with specified amounts of metformin and the expression of NOS in the adipose tissue and hypothalamus was measured by Western blotting. Results show that metformin exhibited a biphasic effect on NOS activity in vitro. Expression of metformin was differentially altered in the hypothalamus and adipose tissues of the normal and ob/ob animals that were treated with metformin. Further, a significant decrease in food intake occurred in the (ob/ob) mice that received metformin. This decrease in food intake was not accompanied by changes in serum glucose. At inhibitory concentrations, hypothalamic NOS expression changes differentially in normal and ob/ob mice. In normal mice, metformin stimulated NOS expression, while in ob/ob mice there was an inhibition. NOS expression increased in brown adipose tissue of metformin treated control mice, while no such increase was observed in ob/ob mice. No effect of metformin was observed in white adipose tissue of control or obese mice. Thus, metformin may produce anorectic effects through modulation of NOS.


Assuntos
Inibidores Enzimáticos/farmacologia , Metformina/farmacologia , Óxido Nítrico Sintase/biossíntese , Obesidade/enzimologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/enzimologia , Animais , Glicemia/análise , Western Blotting , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/enzimologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Camundongos , Camundongos Obesos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Obesidade/genética , Extratos de Tecidos , Aumento de Peso/efeitos dos fármacos
19.
J Pharmacol Exp Ther ; 299(2): 536-41, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11602664

RESUMO

Peripherally administered cytokines profoundly affect the central nervous system (CNS). One mechanism by which they could affect the CNS is by crossing the blood-brain barrier (BBB) to interact directly with brain receptors. Human and murine IL-1alpha (hIL-1alpha; mIL-1alpha) are transported across the murine BBB with a high rate of transport into the posterior division of the septum (PDS), but it is unknown whether BBB transport is relevant to their actions. Here, we injected species-specific blocking antibodies into the PDS to determine whether transport across the BBB is required for blood-borne hIL-1alpha to affect memory. Retention was impaired in a dose-dependent manner when hIL-1alpha was injected either by tail vein (i.v.) or into the PDS, with the PDS route being 1000 times more potent. About 70% of the memory impairment induced by i.v. hIL-1alpha was reversed by injecting a blocking antibody (Ab) specific for hIL-1alpha into the PDS. This shows that much of the memory impairment induced by hIL-1alpha depends on its ability to cross the BBB. Ab specific for mIL-1alpha was also effective in reversing memory impairment, showing that hIL-1alpha releases mIL-1alpha from endogenous stores. Whether the mIL-1alpha was released from peripheral stores, which would require it to cross the BBB, or from brain stores is unknown. In conclusion, these results show that exogenous, blood-borne hIL-1alpha affects memory by releasing mIL-1alpha from endogenous stores and by crossing the BBB to act at sites within the PDS.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Interleucina-1/farmacologia , Memória/efeitos dos fármacos , Septo do Cérebro/metabolismo , Septo do Cérebro/fisiologia , Algoritmos , Animais , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Humanos , Injeções Intravenosas , Interleucina-1/administração & dosagem , Interleucina-1/metabolismo , Camundongos , Camundongos Endogâmicos ICR
20.
Toxicol Sci ; 63(2): 196-207, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11568363

RESUMO

Microarrays are a new technology used to study global gene expression and to decipher biological pathways. In the current study, microarrays were used to examine gene expression patterns associated with cisplatin-mediated nephrotoxicity. Sprague-Dawley rats received either single or seven daily ip doses of cisplatin (0.5 or 1 mg/kg/day) or the inactive isomer transplatin (1 or 3 mg/kg/day). Histopathological evaluation revealed renal proximal tubular necrosis in animals that received cisplatin for 7 days, but no hepatotoxic findings. Microarray analyses were performed using rat specific arrays containing 250 toxicity-related genes. Prominent gene expression changes were observed only in the kidneys of rats that received cisplatin for 7 days. Mechanistically, the gene expression pattern elicited by cisplatin (e.g., Bax upward arrow and SMP-30 downward arrow) suggested the occurrence of apoptosis and the perturbation of intracellular calcium homeostasis. The induction of multidrug resistance genes (MDR1 upward arrow, P-gp upward arrow) and tissue remodeling proteins (clusterin upward arrow, IGFBP-1 upward arrow, and TIMP-1 upward arrow) indicated the development of cisplatin resistance and tissue regeneration. Select gene expression changes were further confirmed by TaqMan analyses. Gene expression changes were not observed in the liver following cisplatin administration. In contrast to these in vivo findings, studies using NRK-52E kidney epithelial cells and clone-9 liver cells suggested that liver cells were more sensitive to cisplatin treatment. The discrepancies between the in vivo and in vitro results suggest that caution should be taken when extrapolating data from in vivo to in vitro systems. Nonetheless, the current study elucidates the biochemical pathways involved in cisplatin toxicity and demonstrates the utility of microarrays in toxicological studies.


Assuntos
Cisplatino/toxicidade , Expressão Gênica/efeitos dos fármacos , Rim/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular , Cisplatino/administração & dosagem , Clusterina , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Genes MDR/efeitos dos fármacos , Glicoproteínas/metabolismo , Hepatócitos/efeitos dos fármacos , Injeções Intraperitoneais , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Necrose Tubular Aguda/induzido quimicamente , Necrose Tubular Aguda/metabolismo , Fígado/efeitos dos fármacos , Masculino , Chaperonas Moleculares/metabolismo , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Sulfotransferases , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Proteína X Associada a bcl-2
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