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1.
J Eur Acad Dermatol Venereol ; 38(6): 1112-1120, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38279575

RESUMEN

OBJECTIVE: A3 adenosine receptor (A3AR) is overexpressed in the skin and peripheral blood mononuclear cells of psoriasis patients. We investigated the efficacy/safety of piclidenoson (CF101), an orally bioavailable A3AR agonist that inhibits IL-17 and IL-23 production in keratinocytes, in moderate-to-severe plaque psoriasis. METHODS: The randomized, placebo- and active-controlled, double-blind phase 3 COMFORT-1 trial randomized patients (3:3:3:2) to piclidenoson 2 mg BID, piclidenoson 3 mg BID, apremilast 30 mg BID or placebo. At Week 16, patients in the placebo arm were re-randomized (1:1:1) to piclidenoson 2 mg BID, piclidenoson 3 mg BID or apremilast 30 mg BID. The primary end point was the proportion of patients achieving ≥75% improvement in Psoriasis Area and Severity Index (PASI) from baseline (PASI-75) at Week 16 versus placebo. RESULTS: A total of 529 patients were randomized and received ≥1 dose of study medication (safety population). The efficacy analysis population for the primary end point included 426 patients (piclidenoson 2 mg BID, 127; piclidenoson 3 mg BID, 103; apremilast, 118; placebo, 78). Piclidenoson at 2 and 3 mg BID exhibited similar efficacy. The primary end point was met with the 3 mg BID dose: PASI 75 rate of 9.7% versus 2.6% for piclidenoson versus placebo, p = 0.037. The PASI responses with piclidenoson continued to increase throughout the study period in a linear manner. At week 32, analysis in the per-protocol population showed that a greater proportion of patients in the piclidenoson 3 mg BID arm (51/88, 58.0%) achieved improvement from baseline in Psoriasis Disability Index (PDI) compared to apremilast (59/108, 55.1%), and the test for noninferiority trended towards significance (p = 0.072). The safety/tolerability profile of piclidenoson was excellent and superior to apremilast. CONCLUSIONS: Piclidenoson demonstrated efficacy responses that increased over time alongside a favourable safety profile. These findings support its continued clinical development as a psoriasis treatment (ClinicalTrials.gov identifier: NCT03168256).


Asunto(s)
Psoriasis , Talidomida , Humanos , Psoriasis/tratamiento farmacológico , Masculino , Método Doble Ciego , Femenino , Persona de Mediana Edad , Adulto , Talidomida/análogos & derivados , Talidomida/uso terapéutico , Talidomida/efectos adversos , Talidomida/administración & dosificación , Índice de Severidad de la Enfermedad , Adenosina/análogos & derivados
2.
Am J Physiol Lung Cell Mol Physiol ; 310(11): L1218-32, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27130530

RESUMEN

Chronic lung disease of prematurity (CLD) is a frequent sequela of premature birth and oxygen toxicity is a major associated risk factor. Impaired alveolarization, scarring, and inflammation are hallmarks of CLD. Mast cell hyperplasia is a feature of CLD but the role of mast cells in its pathogenesis is unknown. We hypothesized that mast cell hyperplasia is a consequence of neonatal hyperoxia and contributes to CLD. Additionally, mast cell products may have diagnostic and prognostic value in preterm infants predisposed to CLD. To model CLD, neonatal wild-type and mast cell-deficient mice were placed in an O2 chamber delivering hyperoxic gas mixture [inspired O2 fraction (FiO2 ) of 0.8] (HO) for 2 wk and then returned to room air (RA) for an additional 3 wk. Age-matched controls were kept in RA (FiO2 of 0.21). Lungs from HO mice had increased numbers of mast cells, alveolar simplification and enlargement, and increased lung compliance. Mast cell deficiency proved protective by preserving air space integrity and lung compliance. The mast cell mediators ß-hexosaminidase (ß-hex), histamine, and elastase increased in the bronchoalveolar lavage fluid of HO wild-type mice. Tracheal aspirate fluids (TAs) from oxygenated and mechanically ventilated preterm infants were analyzed for mast cell products. In TAs from infants with confirmed cases of CLD, ß-hex was elevated over time and correlated with FiO2 Mast cell exosomes were also present in the TAs. Collectively, these data show that mast cells play a significant role in hyperoxia-induced lung injury and their products could serve as potential biomarkers in evolving CLD.


Asunto(s)
Displasia Broncopulmonar/patología , Exosomas/metabolismo , Hiperoxia/patología , Mastocitos/metabolismo , Animales , Animales Recién Nacidos , Displasia Broncopulmonar/inmunología , Displasia Broncopulmonar/metabolismo , Células Cultivadas , Humanos , Hiperoxia/inmunología , Hiperoxia/metabolismo , Recién Nacido , Pulmón/inmunología , Pulmón/patología , Ratones , Proteoma/metabolismo , Tráquea/metabolismo
3.
Diabet Med ; 32(7): 972-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25662770

RESUMEN

AIMS: To evaluate the glomerular haemodynamic profile of patients with Type 1 diabetes with either renal hyperfiltration (GFR ≥ 135 ml/min/1.73 m2 ) or renal normofiltration (GFR 90-134 ml/min/1.73 m2 ) during euglycaemic and hyperglycaemic conditions, and to compare this profile with that of a similar group of healthy control subjects. METHODS: Gomez's equations were used to derive afferent and efferent arteriolar resistances, glomerular hydrostatic pressure and filtration pressure. RESULTS: At baseline, during clamped euglycaemia, patients with Type 1 diabetes and hyperfiltration had lower mean ± sd afferent arteriolar resistance than both those with Type 1 diabetes and normofiltration (914 ± 494 vs. 2065 ± 597 dyne/s/cm5 ; P < 0.001) and healthy control subjects (1676 ± 707 dyne/s/cm(5) ; p < 0.001). By contrast, efferent arteriolar resistance was similar in the three groups. Patients with Type 1 diabetes and hyperfiltration also had higher mean ± sd glomerular hydrostatic pressure than both healthy control subjects and patients with Type 1 diabetes and normofiltration (66 ± 6 vs. 60 ± 3 vs. 55 ± 3 mmHg; P < 0.05). Similar findings for afferent arteriolar resistance, efferent arteriolar resistance, glomerular hydrostatic pressure and filtration pressure were observed during clamped hyperglycaemia. CONCLUSION: Hyperfiltration in Type 1 diabetes is primarily driven by alterations in afferent arteriolar resistance rather than efferent arteriolar resistance. Renal protective therapies should focus on afferent renal arteriolar mechanisms through the use of pharmacological agents that target tubuloglomerular feedback, including sodium-glucose cotransporter 2 inhibitors and incretins.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Nefropatías Diabéticas/fisiopatología , Glomerulonefritis/complicaciones , Hiperglucemia/fisiopatología , Glomérulos Renales/fisiopatología , Circulación Renal , Adulto , Vías Aferentes/fisiopatología , Algoritmos , Arteriolas/inervación , Arteriolas/fisiopatología , Estudios de Cohortes , Diabetes Mellitus Tipo 1/sangre , Vías Eferentes/fisiopatología , Femenino , Barrera de Filtración Glomerular/irrigación sanguínea , Barrera de Filtración Glomerular/inervación , Barrera de Filtración Glomerular/fisiopatología , Tasa de Filtración Glomerular , Glomerulonefritis/fisiopatología , Técnica de Clampeo de la Glucosa , Humanos , Hiperglucemia/prevención & control , Glomérulos Renales/irrigación sanguínea , Glomérulos Renales/inervación , Masculino , Resistencia Vascular , Adulto Joven
4.
Mol Psychiatry ; 18(9): 1006-17, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23089634

RESUMEN

Endogenous glucocorticoids are essential for mobilizing energy resources, restraining inflammatory responses and coordinating behavior to an immune challenge. Impaired glucocorticoid receptor (GR) function has been associated with impaired metabolic processes, enhanced inflammation and exaggerated sickness and depressive-like behaviors. To discern the molecular mechanisms underlying GR regulation of physiologic and behavioral responses to a systemic immune challenge, GR(dim) mice, in which absent GR dimerization leads to impaired GR-DNA-binding-dependent mechanisms but intact GR protein-protein interactions, were administered low-dose lipopolysaccharide (LPS). GR(dim)-LPS mice exhibited elevated and prolonged levels of plasma corticosterone (CORT), interleukin (IL)-6 and IL-10 (but not plasma tumor necrosis factor-α (TNFα)), enhanced early expression of brain TNFα, IL-1ß and IL-6 mRNA levels, and impaired later central TNFα mRNA expression. Exaggerated sickness behavior (lethargy, piloerection, ptosis) in the GR(dim)-LPS mice was associated with increased early brain proinflammatory cytokine expression and late plasma CORT levels, but decreased late brain TNFα expression. GR(dim)-LPS mice also exhibited sustained locomotor impairment in the open field, body weight loss and metabolic alterations measured by indirect calorimetry, as well as impaired thermoregulation. Taken together, these data indicate that GR dimerization-dependent DNA-binding mechanisms differentially regulate systemic and central cytokine expression in a cytokine- and time-specific manner, and are essential for the proper regulation and recovery of multiple physiologic responses to low-dose endotoxin. Moreover, these results support the concept that GR protein-protein interactions are not sufficient for glucocorticoids to exert their full anti-inflammatory effects and suggest that glucocorticoid responses limited to GR monomer-mediated transcriptional effects could predispose individuals to prolonged behavioral and metabolic sequelae of an enhanced inflammatory state.


Asunto(s)
Dimerización , Conducta de Enfermedad/efectos de los fármacos , Inflamación/inducido químicamente , Lipopolisacáridos/toxicidad , Receptores de Glucocorticoides/metabolismo , Animales , Temperatura Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Dióxido de Carbono , Corticosterona/sangre , Citocinas/sangre , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , ARN Mensajero/metabolismo , Telemetría , Factores de Tiempo
5.
eNeuro ; 10(10)2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37816595

RESUMEN

Lysosomes are acidic organelles that traffic throughout neurons delivering catabolic enzymes to distal regions of the cell and maintaining degradative demands. Loss of function mutations in the gene GBA encoding the lysosomal enzyme glucocerebrosidase (GCase) cause the lysosomal storage disorder Gaucher's disease (GD) and are the most common genetic risk factor for synucleinopathies like Parkinson's disease (PD) and dementia with Lewy bodies (DLB). GCase degrades the membrane lipid glucosylceramide (GlcCer) and mutations in GBA, or inhibiting its activity, results in the accumulation of GlcCer and disturbs the composition of the lysosomal membrane. The lysosomal membrane serves as the platform to which intracellular trafficking complexes are recruited and activated. Here, we investigated whether lysosomal trafficking in axons was altered by inhibition of GCase with the pharmacological agent Conduritol B Epoxide (CBE). Using live cell imaging in human male induced pluripotent human stem cell (iPSC)-derived forebrain neurons, we demonstrated that lysosomal transport was similar in both control and CBE-treated neurons. Furthermore, we tested whether lysosomal rupture, a process implicated in various neurodegenerative disorders, was affected by inhibition of GCase. Using L-leucyl-L-leucine methyl ester (LLoME) to induce lysosomal membrane damage and immunocytochemical staining for markers of lysosomal rupture, we found no difference in susceptibility to rupture between control and CBE-treated neurons. These results suggest the loss of GCase activity does not contribute to neurodegenerative disease by disrupting either lysosomal transport or rupture.


Asunto(s)
Células Madre Pluripotentes Inducidas , Enfermedades Neurodegenerativas , Masculino , Humanos , Glucosilceramidasa/genética , Glucosilceramidasa/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Transporte Axonal , Neuronas/metabolismo , Prosencéfalo/metabolismo , Lisosomas/metabolismo , alfa-Sinucleína/metabolismo
6.
Psychol Med ; 42(11): 2395-404, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22436619

RESUMEN

BACKGROUND: It is clinically important to understand the factors that increase the likelihood of the frequent and recurrent suicide attempts seen in those with borderline personality disorder (BPD). Although several studies have examined this subject in a cross-sectional manner, the aim of this study was to determine the most clinically relevant baseline and time-varying predictors of suicide attempts over 16 years of prospective follow-up among patients with BPD. METHOD: Two-hundred and ninety in-patients meeting Revised Diagnostic Interview for Borderlines (DIB-R) and DSM-III-R criteria for BPD were assessed during their index admission using a series of semistructured interviews and self-report measures. These subjects were then reassessed using the same instruments every 2 years. The generalized estimating equations (GEE) approach was used to model the odds of suicide attempts in longitudinal analyses, controlling for assessment period, yielding an odds ratio (OR) and 95% confidence interval (CI) for each predictor. RESULTS: Nineteen variables were found to be significant bivariate predictors of suicide attempts. Eight of these, seven of which were time-varying, remained significant in multivariate analyses: diagnosis of major depressive disorder (MDD), substance use disorder (SUD), post-traumatic stress disorder (PTSD), presence of self-harm, adult sexual assault, having a caretaker who has completed suicide, affective instability, and more severe dissociation. CONCLUSIONS: The results of this study suggest that prediction of suicide attempts among borderline patients is complex, involving co-occurring disorders, co-occurring symptoms of BPD (self-harm, affective reactivity and dissociation), adult adversity, and a family history of completed suicide.


Asunto(s)
Trastorno de Personalidad Limítrofe/epidemiología , Trastornos Mentales/epidemiología , Intento de Suicidio/estadística & datos numéricos , Adulto , Trastorno de Personalidad Limítrofe/complicaciones , Comorbilidad , Femenino , Humanos , Estudios Longitudinales , Masculino , Factores de Riesgo , Adulto Joven
7.
J Eur Acad Dermatol Venereol ; 26(3): 361-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21504485

RESUMEN

AIMS: CF101 demonstrated a marked anti-inflammatory effect in Phase 2 studies conducted in patients with rheumatoid arthritis and dry eye syndrome. The aim of this study was to evaluate the safety and efficacy of CF101 for the treatment of patients with moderate to severe plaque-type psoriasis. MATERIALS AND METHODS: This was a phase 2, multicentre, randomized, double-blind, dose-ranging, placebo-controlled study. Seventy five patients with moderate to severe plaque-type psoriasis were enrolled, randomized and treated with CF101 (1, 2, or 4 mg) or placebo administered orally twice daily for 12 weeks. Safety and change from base line of Psoriasis Area and Severity Index (PASI) score and physician's global assessment (PGA) score over 12 weeks. RESULTS: In the 2 mg CF101-treated group, a progressive improvement in the mean change from baseline in the PASI score vs. placebo throughout the study period was observed, with a statistically significant difference on weeks 8 and 12 (P = 0.047; P = 0.031, respectively). In this group, 35.3% of the patients achieved PASI ≥ 50 response, and 23.5% of the patients achieved a PGA score of 0 or 1. CF101 was safe and well tolerated. CONCLUSIONS: CF101 was well tolerated and demonstrated clear evidence of efficacy in patients with moderate to severe plaque psoriasis.


Asunto(s)
Adenosina/análogos & derivados , Psoriasis/tratamiento farmacológico , Adenosina/uso terapéutico , Adolescente , Adulto , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placebos , Resultado del Tratamiento
8.
J Prev Alzheimers Dis ; 9(4): 635-645, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36281667

RESUMEN

BACKGROUND: Neurodegenerative diseases are devastating conditions that most commonly affect individuals 65 years and older. Currently there are no effective treatments or cures for neurodegenerative diseases, and therapeutics that selectively target the underlying causes of these diseases are needed. Epichaperomes play a major role in the maintenance and progression of neuronal pathology. Inhibiting epichaperomes induces degradation of disease associated proteins and is a promising therapeutic approach to treat neurodegenerative diseases, in particular Alzheimer's Disease and amyotrophic lateral sclerosis. OBJECTIVES: This Phase 1 clinical study evaluated the safety, tolerability, pharmacokinetics, and bioavailability of icapamespib, a purine scaffold inhibitor of epichaperomes that is specific to epichaperomes, in healthy subjects. DESIGN: Double-blind, placebo-controlled dose escalating single ascending dose and multiple ascending doses and an unblinded two-period cross-over bioavailability study design. SETTING: Single site in the United States. PARTICIPANTS: Healthy men or women of 18 to 60 years of age, inclusive, for Part 1 (single ascending dose), ≥ 60 years of age for Part 2 (multiple ascending dose), or 18 to 49 years of age for Part 3 (bioavailability). TREATMENT: In the single ascending dose group, oral single doses (10, 20, and 30 mg icapamespib or placebo) were administered to healthy non-elderly subjects. In the multiple ascending dose group, multiple doses (20 and 30 mg icapamespib once daily for 7 days or placebo) were administered to healthy elderly subjects. In the bioavailability group, the bioavailability of once daily oral icapamespib solution and tablet was assessed in healthy non elderly subjects. MEASUREMENTS: Safety was evaluated based on assessments of treatment-emergent adverse events, physical examinations, clinical laboratory tests (hematology, clinical chemistry, and urinalysis), vital signs, and 12-lead electrocardiograms. Icapamespib concentration was evaluated in plasma and cerebrospinal fluid, the latter in Part 2 (multiple ascending dose) only. RESULTS: Forty-eight subjects in total were randomized and assessed for tolerability, pharmacokinetics, and bioavailability parameters as follows: 24 subjects in Part 1 (single ascending dose) with PU-AD 10 mg (n = 6), 20 mg (n = 6), 30 mg (n = 6), and placebo (n = 6); 16 subjects in Part 2 (multiple ascending dose) with icapamespib 20 mg (n = 6), 30 mg (n = 6), and placebo (n = 4); and 8 subjects in Part 3 (bioavailability) crossed-over between icapamespib 30 mg (tablet) and icapamespib 30 mg (oral solution). Single doses of icapamespib up to 30 mg and multiple doses of icapamespib up to 30 mg for 7 days were generally safe and well tolerated in healthy non-elderly and elderly subjects. Treatment-emergent adverse events were mild, with headache being the most common treatment-emergent adverse event. Mean icapamespib exposure (area under the curve) was dose-proportional over the dose range tested. The median time to maximum observed plasma concentration ranged from 1.00 to 2.00 h across single ascending dose, multiple ascending dose, and bioavailability groups; icapamespib exposure was 50% higher in elderly subjects compared with non-elderly subjects but was well tolerated. CONCLUSIONS: The study provides clinical evidence of the safety of icapamespib in healthy non elderly and elderly subjects and supports the advancement of icapamespib to Phase 2 evaluation in Alzheimer's Disease and other neurodegenerative diseases.


Asunto(s)
Enfermedad de Alzheimer , Adulto , Masculino , Humanos , Femenino , Persona de Mediana Edad , Anciano , Relación Dosis-Respuesta a Droga , Enfermedad de Alzheimer/tratamiento farmacológico , Método Doble Ciego , Estudios Cruzados , Purinas
9.
Clin Exp Allergy ; 40(8): 1130-41, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20545704

RESUMEN

It has been suggested that there are several distinct phenotypes of childhood asthma or childhood wheezing. Here, we review the research relating to these phenotypes, with a focus on the methods used to define and validate them. Childhood wheezing disorders manifest themselves in a range of observable (phenotypic) features such as lung function, bronchial responsiveness, atopy and a highly variable time course (prognosis). The underlying causes are not sufficiently understood to define disease entities based on aetiology. Nevertheless, there is a need for a classification that would (i) facilitate research into aetiology and pathophysiology, (ii) allow targeted treatment and preventive measures and (iii) improve the prediction of long-term outcome. Classical attempts to define phenotypes have been one-dimensional, relying on few or single features such as triggers (exclusive viral wheeze vs. multiple trigger wheeze) or time course (early transient wheeze, persistent and late onset wheeze). These definitions are simple but essentially subjective. Recently, a multi-dimensional approach has been adopted. This approach is based on a wide range of features and relies on multivariate methods such as cluster or latent class analysis. Phenotypes identified in this manner are more complex but arguably more objective. Although phenotypes have an undisputed standing in current research on childhood asthma and wheezing, there is confusion about the meaning of the term 'phenotype' causing much circular debate. If phenotypes are meant to represent 'real' underlying disease entities rather than superficial features, there is a need for validation and harmonization of definitions. The multi-dimensional approach allows validation by replication across different populations and may contribute to a more reliable classification of childhood wheezing disorders and to improved precision of research relying on phenotype recognition, particularly in genetics. Ultimately, the underlying pathophysiology and aetiology will need to be understood to properly characterize the diseases causing recurrent wheeze in children.


Asunto(s)
Asma/clasificación , Fenotipo , Asma/fisiopatología , Niño , Humanos , Ruidos Respiratorios/clasificación , Ruidos Respiratorios/fisiopatología
10.
eNeuro ; 7(6)2020.
Artículo en Inglés | MEDLINE | ID: mdl-33067366

RESUMEN

Impairment of axonal transport is an early pathologic event that precedes neurotoxicity in Alzheimer's disease (AD). Soluble amyloid-ß oligomers (AßOs), a causative agent of AD, activate intracellular signaling cascades that trigger phosphorylation of many target proteins, including tau, resulting in microtubule destabilization and transport impairment. Here, we investigated how KIF1A, a kinesin-3 family motor protein required for the transport of neurotrophic factors, is impaired in mouse hippocampal neurons treated with AßOs. By live cell imaging, we observed that AßOs inhibit transport of KIF1A-GFP similarly in wild-type and tau knock-out neurons, indicating that tau is not required for this effect. Pharmacological inhibition of glycogen synthase kinase 3ß (GSK3ß), a kinase overactivated in AD, prevented the transport defects. By mass spectrometry on KIF1A immunoprecipitated from transgenic AD mouse brain, we detected phosphorylation at S402, which conforms to a highly conserved GSK3ß consensus site. We confirmed that this site is phosphorylated by GSK3ß in vitro Finally, we tested whether a phosphomimic of S402 could modulate KIF1A motility in control and AßO-treated mouse neurons and in a Golgi dispersion assay devoid of endogenous KIF1A. In both systems, transport driven by mutant motors was similar to that of WT motors. In conclusion, GSK3ß impairs KIF1A transport but does not regulate motor motility at S402. Further studies are required to determine the specific phosphorylation sites on KIF1A that regulate its cargo binding and/or motility in physiological and disease states.


Asunto(s)
Enfermedad de Alzheimer , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Cinesinas , Animales , Transporte Axonal , Cinesinas/genética , Cinesinas/metabolismo , Ratones , Neuronas/metabolismo , Fosforilación , Proteínas tau/genética , Proteínas tau/metabolismo
11.
Neuroimage Clin ; 25: 102135, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31901789

RESUMEN

Deep brain stimulation (DBS) for Parkinson's disease (PD) is an established advanced therapy that produces therapeutic effects through high frequency stimulation. Although this therapeutic option leads to improved clinical outcomes, the mechanisms of the underlying efficacy of this treatment are not well understood. Therefore, investigation of DBS and its postoperative effects on brain architecture is of great interest. Diffusion weighted imaging (DWI) is an advanced imaging technique, which has the ability to estimate the structure of white matter fibers; however, clinical application of DWI after DBS implantation is challenging due to the strong susceptibility artifacts caused by implanted devices. This study aims to evaluate the feasibility of generating meaningful white matter reconstructions after DBS implantation; and to subsequently quantify the degree to which these tracts are affected by post-operative device-related artifacts. DWI was safely performed before and after implanting electrodes for DBS in 9 PD patients. Differences within each subject between pre- and post-implantation FA, MD, and RD values for 123 regions of interest (ROIs) were calculated. While differences were noted globally, they were larger in regions directly affected by the artifact. White matter tracts were generated from each ROI with probabilistic tractography, revealing significant differences in the reconstruction of several white matter structures after DBS. Tracts pertinent to PD, such as regions of the substantia nigra and nigrostriatal tracts, were largely unaffected. The aim of this study was to demonstrate the feasibility and clinical applicability of acquiring and processing DWI post-operatively in PD patients after DBS implantation. The presence of global differences provides an impetus for acquiring DWI shortly after implantation to establish a new baseline against which longitudinal changes in brain connectivity in DBS patients can be compared. Understanding that post-operative fiber tracking in patients is feasible on a clinically-relevant scale has significant implications for increasing our current understanding of the pathophysiology of movement disorders, and may provide insights into better defining the pathophysiology and therapeutic effects of DBS.


Asunto(s)
Encéfalo/diagnóstico por imagen , Estimulación Encefálica Profunda/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Neuroimagen/métodos , Enfermedad de Parkinson/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Anciano , Encéfalo/fisiopatología , Estudios de Factibilidad , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/terapia , Sustancia Blanca/fisiopatología
12.
Science ; 227(4692): 1345-7, 1985 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-2983423

RESUMEN

Light is produced by recombinant Escherichia coli that contain lux genes cloned from the marine bacterium Vibrio fischeri. The bioluminescence phenotype requires genes for regulatory and biochemical functions, the latter encoded by five lux genes contained in a single operon. These lux genes were disconnected from their native promoter and inserted into the transposon mini-Mu. The resulting transposon, mini-Mulux, could induce mutations by insertional inactivation of a target gene, and the lux DNA was oriented to align target gene transcription with that of the lux genes. Genes in Escherichia coli and Vibrio parahaemolyticus were mutagenized, and mutants containing transposon-generated lux gene fusions produced light as a function of target gene transcription. Light production offers a simple, sensitive, in vivo indicator of gene expression.


Asunto(s)
ADN Recombinante/metabolismo , Regulación de la Expresión Génica , Proteínas Luminiscentes/genética , Elementos Transponibles de ADN , Escherichia coli/genética , Luciferasas/genética , Luminiscencia , Mutación , Fenotipo , Biosíntesis de Proteínas , Vibrio/genética , Vibrio parahaemolyticus/metabolismo
13.
Science ; 169(3949): 985-7, 1970 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-17838175

RESUMEN

Penicillium simplicissimum, isolated from weathering basalt, produced citric acid when grown in a glucose-mineral salts medium with basalt, granite, granodiorite, rhyolite, andesite, peridotite, dunite, or quartzite. After 7 days' growth as much as 31 percent of the silicon, 11 percent of the aluminum, 64 percent of the iron, and 59 percent of the magnesium in some of the rocks were solubilized, and a number of rocks showed altered infrared absorption in the silicon-oxygen vibration region.

14.
Science ; 196(4286): 170-2, 1977 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-322276

RESUMEN

Flagellar antigens are specified by two genes, H1 and H2. The expression of these genes is regulated such that only one gene activity, or phase, is expressed at a given time. Molecular cloning techniques were used to isolate the segments of Salmonella DNA which contain these genetic loci. Heteroduplex analyses revealed an anomaly in the cloned fragment, that is, and apparent inversion, which was shown to be adjacent to the H2 gene. A correlation was demonstrated between the phase state of the H2 gene and the sequence of the adjacent segment. We propose that an inversion of this region is the phase-determining event in flagellar gene expression in Salmonella.


Asunto(s)
Antígenos Bacterianos , ADN Bacteriano/metabolismo , ADN Recombinante , Genes , Salmonella/metabolismo , Inversión Cromosómica , Colicinas , Colifagos/metabolismo , Enzimas de Restricción del ADN/metabolismo , ADN Viral/metabolismo , Escherichia coli/metabolismo , Flagelos/inmunología , Plásmidos , Salmonella/inmunología , Salmonella/ultraestructura , Transducción Genética , Transformación Genética
15.
Science ; 209(4463): 1370-4, 1980 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-6251543

RESUMEN

Phase variation in bacteria is regulated by homologous recombination at a specific DNA site. This recombinational event causes the inversion of a 970-base-pair DNA sequence that includes the promoter necessary for transcription of a flagellar gene. The invertible segment is flanked by two sites that are necessary for the inversion and contains a gene (hin) whose product mediates the inversion event. The hin gene shows extensive homology with the TnpR gene carried on the Tn3 transposon. It is also homologous with the gin gene carried on bacteriophage mu. These relationships suggest that the phase variation system may have evolved by the association of a transposon with a resident gene and the subsequent specialization of these elements to regulate flagellar antigen expression.


Asunto(s)
Proteínas Bacterianas/genética , Elementos Transponibles de ADN , Flagelina/genética , Salmonella/genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN Bacteriano/genética , Genes , Recombinación Genética
16.
Science ; 214(4522): 813-5, 1981 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-7292014

RESUMEN

Using the activity-dependent 2-[14C]deoxy-D-glucose technique, we have demonstrated a columnar organization of spatial frequency--specific sensitivity in striate cortex. Cats viewing patterns containing a single spatial frequency presented at all orientations show columns of increased deoxyglucose uptake extending through all cortical layers. A control stimulus containing all spatial frequencies presented at all orientations produces no columnar density differences within the striate cortex.


Asunto(s)
Corteza Visual/citología , Percepción Visual/fisiología , Animales , Autorradiografía , Mapeo Encefálico , Gatos , Desoxiglucosa , Orientación/fisiología , Percepción Espacial/fisiología , Corteza Visual/fisiología
17.
Science ; 167(3918): 773-5, 1970 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-5410554

RESUMEN

The hypothesis that the moon could harbor viable life forms was not verified on analysis of the first samnples from the Apollo 11 mission. Biological examnination of 50 grainis of the butlk fines confirmn the negative results obtained by the Manned Spacecraft Center quarantine teamyz. No viable life forms, including terrestrial contaminants, were found when the sample was tested in 300 separate environmtenits. Only colored illorganiic artifacts, resembling mnicrobial clonies, appeared aroun1cd some particles. Manned Spacecraft Center, Houston.


Asunto(s)
Medio Ambiente Extraterrestre , Microbiología , Fenómenos Astronómicos , Astronomía
18.
Science ; 218(4575): 902-4, 1982 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-7134981

RESUMEN

We have anatomically analyzed retinotopic organization using the 14C-labeled 2-deoxy-D-glucose method. The method has several advantages over conventional electrophysiological mapping techniques. In the striate cortex, the anatomical substrate for retinotopic organization is surprisingly well ordered, and there seems to be a systematic relationship between ocular dominance strips and cortical magnification. The 2-deoxyglucose maps in this area appear to be largely uninfluenced by known differences in long-term metabolic activity. This method should prove useful in analyzing retinotopic organization in various visual areas of the brain and in different species.


Asunto(s)
Retina/fisiología , Corteza Visual/citología , Animales , Mapeo Encefálico , Desoxiglucosa , Lateralidad Funcional , Macaca , Reconocimiento Visual de Modelos/fisiología , Percepción Visual/fisiología
19.
Science ; 218(4574): 791-3, 1982 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-10636771

RESUMEN

Genes for the luciferase enzyme of Vibrio harveyi were isolated in Escherichia coli by a general method in which nonluminous, transposon insertion mutants were used. Conditions necessary for light production in E. coli were examined. Stimulation of transcription of the genes for luciferase (lux A and lux B) was required for efficient synethesis of luciferase. To enhance transcription bacteriophage promoter elements were coupled to the cloned lux gene fragments.


Asunto(s)
Luciferasas/biosíntesis , Vibrio/genética , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/fisiología , Genes Bacterianos , Luciferasas/genética , Mediciones Luminiscentes , Vibrio/enzimología , Vibrio/fisiología
20.
Science ; 220(4598): 737-9, 1983 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-6301017

RESUMEN

The functional organization of the second cortical visual area was examined with three different anatomical markers: 2-[14C]deoxy-D-glucose, cytochrome oxidase, and various myelin stains. All three markers revealed strips running throughout the area, parallel to the cortical surface. The boundaries of these strips provide an anatomical criterion for defining the borders of this extrastriate region. Further, the demonstration of these strips allows a functional and anatomical analysis of modules in the area, just as the recent demonstration of spots in the primary visual cortex has allowed an analysis of modules there. The strips differ structurally and functionally from interstrip regions and these differences are similar to those seen between the spots and the interspot regions in the primary visual cortex. In the macaque the strips and spots differ with regard to binocular organization.


Asunto(s)
Corteza Visual/anatomía & histología , Animales , Desoxiglucosa/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Macaca , Proteínas de la Mielina/metabolismo , Estimulación Luminosa , Saimiri , Corteza Visual/enzimología , Corteza Visual/fisiología
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