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1.
Pediatr Res ; 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347172

RESUMEN

IMPACT: Findings from this study provide further reassuring evidence that infant exposure through human milk received from lactating individuals who require treatment with remdesivir is negligible.

2.
Ecol Appl ; 32(8): e2709, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36131546

RESUMEN

Variation among populations in life history and intrinsic population characteristics (i.e., population diversity) helps maintain resilience to environmental change and dampen interannual variability in ecosystem services. As a result, ecological variation, and the processes that generate it, is considered central to strategies for managing risks to ecosystems in an increasingly variable and uncertain world. However, characterizing population diversity is difficult, particularly in large and remote regions, which often prevents its formal consideration in management advice. We combined genetic stock identification of archived scale and tissue samples with state-space run-reconstruction models to estimate migration timing and annual return abundance for eight geographically and genetically distinct Chinook salmon populations within the Canadian portion of the Yukon River. We found that among-population variation in migration timing and return abundances resulted in aggregate return migrations that were 2.1 times longer and 1.4 times more stable than if they had composed a single homogeneous population. We then fit state-space spawner-recruitment models to the annual return abundances to characterize among-population diversity in intrinsic productivity and population size and their consequences for the fisheries they support. Productivity and carrying capacity varied among populations by approximately 2.4-fold (2.9 to 6.9 recruits per spawner) and three-fold (8800 to 27,000 spawners), respectively. This diversity implies an equilibrium trade-off between harvesting of the population aggregate and the conservation of individual populations whereby the harvest rate predicted to maximize aggregate harvests comes at the cost of overfishing ~40% of the populations but with a relatively low risk of extirpating the weakest ones. Our findings illustrate how population diversity in one of the largest salmon-producing river basins in the world contributes to fishery stability and food security in a region where salmon have high cultural and subsistence value. More generally, our work demonstrates the utility of molecular analyses of archived biological material for characterizing diversity in biological systems and its benefits and consequences for trade-offs in decision-making.


Asunto(s)
Explotaciones Pesqueras , Salmón , Animales , Salmón/genética , Ecosistema , Conservación de los Recursos Naturales , Canadá
3.
Reprod Health ; 17(1): 128, 2020 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-32831069

RESUMEN

BACKGROUND: Retrospective observational studies suggest that transmission of Trypanosoma cruzi does not occur in treated women when pregnant later in life. The level of parasitemia is a known risk factor for congenital transmission. Benznidazole (BZN) is the drug of choice for preconceptional treatment to reduce parasitic load. The fear of treatment-related side effects limits the implementation of the Argentine guideline recommending BZN 60d/300 mg (or equivalent) treatment of T. cruzi seropositive women during the postpartum period to prevent transmission in a future pregnancy. A short and low dose BZN treatment might reduce major side effects and increase compliance, but its efficacy to reduce T. cruzi parasitic load compared to the standard 60d/300 mg course is not yet established. Clinical trials testing alternative BZN courses among women of reproductive age are urgently needed. METHODS AND DESIGN: We are proposing to perform a double-blinded, non-inferiority randomized controlled trial comparing a short low dose 30-day treatment with BZN 150 mg/day (30d/150 mg) vs. BZN 60d/300 mg. We will recruit not previously treated T. cruzi seropositive women with a live birth during the postpartum period in Argentina, randomize them at 6 months postpartum, and follow them up with the following specific aims: Specific aim 1: to measure the effect of BZN 30d/150 mg compared to 60d/300 mg preconceptional treatment on parasitic load measured by the frequency of positive Polymerase Chain Reaction (PCR) (primary outcome) and by real-time quantitative PCR (qPCR), immediately and 10 months after treatment. Specific aim 2: to measure the frequency of serious adverse events and/or any adverse event leading to treatment interruption. TRIAL REGISTRATION: ClinicalTrials.gov . Identifier: NCT03672487 . Registered 14 September 2018.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Nitroimidazoles/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Argentina , Enfermedad de Chagas/diagnóstico , Femenino , Humanos , Carga de Parásitos , Periodo Posparto , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , Trypanosoma cruzi/genética
4.
Anesthesiology ; 120(4): 951-61, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24492326

RESUMEN

BACKGROUND: Anatomic, physiologic, and behavioral studies in animals suggest that spinally released oxytocin should produce analgesia in humans and may also protect from chronic pain after injury. In this article, the authors report preclinical toxicity screening of oxytocin for intrathecal delivery. METHODS: Intrathecal oxytocin, 11 µg (6 U) or vehicle, was injected intrathecally in 24 rats, followed by frequent behavioral assessment and histologic examination of spinal contents 2 or 14 days after injection. In three dogs, a range of intrathecal oxytocin doses (18 to 550 µg in 0.5 ml) was injected followed by physiologic, biochemical, and behavioral assessments. Ten dogs were then randomized to receive five daily injections of intrathecal oxytocin, 550 µg in 0.5 ml, or vehicle with similar assessments and, necropsy and histologic analysis were conducted 2 days later. RESULTS: In rats, intrathecal oxytocin resulted in transient scratching and itching behaviors, without other differences from vehicle. There was no behavioral, gross anatomic, or histologic evidence of neurotoxicity. Dose ranging in dogs suggested mild effects on motor tone, blood pressure, and heart rate at the 550 µg dose. Repeated boluses in dogs did not produce behavioral, biochemical, neurological, gross anatomic, or histologic evidence of neurotoxicity. CONCLUSIONS: Substances, including natural neurotransmitters, may be toxic when administered in pharmacologic doses in the spinal cord. This preclinical toxicity screen in two species suggests that bolus injections of oxytocin in concentrations up to 1,100 µg/ml are unlikely to cause neurotoxicity. The authors also support cautious clinical application of intrathecal oxytocin under regulatory supervision.


Asunto(s)
Oxitócicos/toxicidad , Oxitocina/toxicidad , Animales , Conducta Animal/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Evaluación Preclínica de Medicamentos , Femenino , Estudios de Seguimiento , Frecuencia Cardíaca/efectos de los fármacos , Inyecciones Espinales , Masculino , Oxitócicos/administración & dosificación , Oxitocina/administración & dosificación , Prurito/inducido químicamente , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Crónica
5.
Proc Natl Acad Sci U S A ; 108(16): 6561-6, 2011 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-21464300

RESUMEN

Metabolic, infectious, and tumor cell-intrinsic noxae can all evoke the endoplasmic reticulum (ER) stress response in tumor cells, which is critical for tumor cell growth and cancer progression. Evidence exists that the ER stress response can drive a proinflammatory program in tumor cells and macrophages but, to our knowledge, a role for the tumor ER stress response in influencing macrophages and inflammation in the tumor microenvironment has not been suggested. Here we show that macrophages cultured in conditioned medium from ER-stressed tumor cells become activated, and themselves undergo ER stress with the up-regulation of Grp78, Gadd34, Chop, and Xbp-1 splicing, suggesting a general activation of the ER stress-signaling pathways. Furthermore, these macrophages recapitulate, amplify and expand the proinflammatory response of tumor cells. We term this phenomenon "transmissible" ER stress. Although neither Toll-like receptor (TLR)2 nor interleukin 6 receptor (IL6R) signaling is involved, a reduction was observed in the transmission of ER stress to TLR4 KO macrophages, consistent with the fact that a second signal through TLR4 combined with exposure to tumor ER stress-conditioned medium results in a faster ER stress response and an enhancement of proinflammatory cytokine production in macrophages. The injection of tumor ER stress-conditioned medium into WT mice elicited a generalized ER stress response in the liver. We suggest that transmissible ER stress is a mechanism through which tumor cells can control myeloid cells by directing them toward a proinflammatory phenotype, thus facilitating tumor progression.


Asunto(s)
Retículo Endoplásmico/inmunología , Hígado/inmunología , Macrófagos/inmunología , Proteínas de Neoplasias/inmunología , Neoplasias/inmunología , Respuesta de Proteína Desplegada/inmunología , Animales , Línea Celular Tumoral , Medios de Cultivo Condicionados/farmacología , Retículo Endoplásmico/metabolismo , Chaperón BiP del Retículo Endoplásmico , Regulación Neoplásica de la Expresión Génica , Hígado/metabolismo , Ratones , Ratones Noqueados , Proteínas de Neoplasias/biosíntesis , Neoplasias/metabolismo
6.
J Antimicrob Chemother ; 68(5): 1161-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23335197

RESUMEN

OBJECTIVES: Etravirine has high affinity for plasma drug-binding proteins, such as albumin and α1-acid glycoprotein, which limits the amount of unbound etravirine available to enter the CNS. The objective of this study was to compare total and unbound etravirine concentrations in CSF with plasma concentrations and the in vitro median inhibitory concentration (IC50) for wild-type HIV (0.9 ng/mL). METHODS: Total and bound etravirine concentrations were measured in 17 CSF and plasma pairs by isotope-dilution liquid chromatography tandem mass spectroscopy, radioligand displacement and ultracentrifugation. Unbound etravirine concentrations were calculated from the bound fraction. The dynamic range of the assay was 7.8-2000 (plasma) and 0.78-200 (CSF) ng/mL. RESULTS: Subjects were mostly middle-aged (median 43 years) white (78%) men (89%). All CSF etravirine concentrations were above the limit of quantification. Total and unbound median etravirine concentrations in CSF were 9.5 (IQR 6.4, 26.4) and 0.13 (IQR 0.08, 0.27) ng/mL, respectively. Etravirine was 96% (IQR 94.5, 97.2) protein bound in plasma and 98.4% (IQR 97.8, 98.8) in CSF. Total etravirine in CSF was 4.3% (IQR 3, 5.9) of total and 101% (IQR 76, 160) of unbound etravirine in plasma. There were no significant correlations between unbound etravirine concentrations and concentrations of albumin in plasma or CSF. Unbound etravirine concentrations in CSF did not reach the wild-type IC50 in any of the specimens. CONCLUSIONS: Unbound etravirine may not achieve optimal concentrations to inhibit HIV replication in the CNS.


Asunto(s)
Fármacos Anti-VIH/análisis , Fármacos Anti-VIH/farmacocinética , Líquido Cefalorraquídeo/química , Proteínas/metabolismo , Piridazinas/análisis , Piridazinas/farmacocinética , Adulto , Fármacos Anti-VIH/metabolismo , Cromatografía Líquida de Alta Presión , Estudios de Cohortes , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Concentración 50 Inhibidora , Marcaje Isotópico , Masculino , Persona de Mediana Edad , Nitrilos , Plasma/química , Unión Proteica , Piridazinas/metabolismo , Pirimidinas , Espectrometría de Masas en Tándem , Ultracentrifugación
7.
J Antimicrob Chemother ; 68(3): 684-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23143899

RESUMEN

OBJECTIVES: Higher CSF antiretroviral concentrations may be associated with better control of HIV replication and neurocognitive performance, but only the unbound fraction of antiretrovirals is available to inhibit HIV. Therefore, the objective of this study was to determine total and unbound darunavir concentrations in CSF and compare findings with plasma concentrations as well as the wild-type HIV-1 90% inhibitory concentration (IC(90)). METHODS: Subjects with HIV infection were selected based on the use of darunavir-containing regimens with a twice-daily dosing schedule and availability of stored CSF and matched plasma. Total darunavir was measured by HPLC for plasma or liquid chromatography-tandem mass spectroscopy (LC/MS/MS) for CSF. Plasma unbound darunavir was measured by ultrafiltration and LC/MS/MS. CSF protein binding was determined by competitive binding exchange with radiolabelled darunavir. RESULTS: Twenty-nine matched CSF-plasma pairs were analysed and darunavir was detected in all CSF specimens (median total concentration 55.8 ng/mL), with a CSF unbound fraction of 93.5%. Median fractional penetrance was 1.4% of median total and 9.4% of median unbound plasma concentrations. Unbound darunavir concentrations in CSF exceeded the median IC(90) for wild-type HIV in all subjects by a median of 20.6-fold, despite the relatively low fractional penetrance. Total darunavir concentrations in CSF correlated with both total and unbound darunavir concentrations in plasma. CONCLUSIONS: Darunavir should contribute to the control of HIV replication in the CNS as a component of effective combination antiretroviral regimens.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/farmacocinética , Líquido Cefalorraquídeo/química , Proteínas/metabolismo , Sulfonamidas/administración & dosificación , Sulfonamidas/farmacocinética , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Darunavir , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Plasma/química , Unión Proteica , Manejo de Especímenes/métodos , Espectrometría de Masas en Tándem , Ultrafiltración
8.
Ther Drug Monit ; 35(2): 203-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23503446

RESUMEN

BACKGROUND: Previously published methods for determination of efavirenz (EFV) in human dried blood spots (DBS) use costly and complex liquid chromatography/mass spectrometry. We describe the validation and evaluation of a simple and inexpensive high-performance liquid chromatography method for EFV quantification in human DBS and dried plasma spots (DPS), using ultraviolet detection appropriate for resource-limited settings. METHODS: One hundred microliters of heparinized whole blood or plasma were spotted onto blood collection cards, dried, punched, and eluted. Eluates are injected onto a C-18 reversed phase high-performance liquid chromatography column. EFV is separated isocratically using a potassium phosphate and acetonitrile mobile phase. Ultraviolet detection is at 245 nm. Quantitation is by use of external calibration standards. Following validation, the method was evaluated using whole blood and plasma from HIV-positive patients undergoing EFV therapy. RESULTS: Mean recovery of drug from DBS is 91.5%. The method is linear over the validated concentration range of 0.3125-20.0 µg/mL. A good correlation (Spearman r = 0.96) between paired plasma and DBS EFV concentrations from the clinical samples was observed, and hematocrit level was not found to be a significant determinant of the EFV DBS level. The mean observed C DBS/C plasma ratio was 0.68. A good correlation (Spearman r = 0.96) between paired plasma and DPS EFV concentrations from the clinical samples was observed. The mean percent deviation of DPS samples from plasma samples is 1.68%. CONCLUSIONS: Dried whole blood spot or dried plasma spot sampling is well suited for monitoring EFV therapy in resource-limited settings, particularly when high sensitivity is not essential.


Asunto(s)
Fármacos Anti-VIH/sangre , Benzoxazinas/sangre , Cromatografía de Fase Inversa/métodos , Pruebas con Sangre Seca/métodos , Alquinos , Cromatografía Líquida de Alta Presión/métodos , Ciclopropanos , Humanos , Espectrometría de Masas/métodos , Espectrofotometría Ultravioleta/métodos
9.
Antimicrob Agents Chemother ; 56(4): 1985-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22290964

RESUMEN

Antiretrovirals that reach higher concentrations in cerebrospinal fluid (CSF) are associated with better control of HIV in CSF and possibly better neurocognitive performance. The objective of this study was to determine whether amprenavir (APV) concentrations in CSF are in the therapeutic range. Individuals were selected based on the use of regimens that included fosamprenavir (FPV), a prodrug of APV, and the availability of stored CSF and matched plasma. Total APV was measured in 119 matched CSF-plasma pairs from 75 subjects by high-performance liquid chromatography (HPLC) (plasma) or liquid chromatography tandem mass spectrometry (LC/MS/MS) (CSF). Concentrations were compared to the 50% inhibitory concentration (IC50) for wild-type HIV (5.6 ng/ml). Subjects were predominantly middle-aged (median 44 years) white (57%) men (78%) with AIDS (77%). APV was detected in all but 4 CSF specimens, with a median concentration of 24.8 ng/ml (interquartile range [IQR], 16.2 to 44.0). The median CSF-to-plasma ratio was 0.012 (IQR, 0.008 to 0.018). CSF concentrations correlated with plasma concentrations (rho = 0.61; P < 0.0001) and with postdose sampling interval (rho = -0.29; P = 0.0019). APV concentrations in CSF exceeded the median IC50 for wild-type HIV in more than 97% of CSF specimens with detectable APV by a median of 4.4-fold (IQR, 2.9 to 7.9). We conclude that administration of fosamprenavir should contribute to control of HIV replication in the central nervous system (CNS) as a component of effective antiretroviral regimens.


Asunto(s)
Fármacos Anti-VIH/líquido cefalorraquídeo , Carbamatos/líquido cefalorraquídeo , Sulfonamidas/líquido cefalorraquídeo , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/farmacocinética , Terapia Antirretroviral Altamente Activa , Linfocitos T CD4-Positivos , Carbamatos/administración & dosificación , Carbamatos/farmacocinética , Cromatografía Líquida de Alta Presión , Esquema de Medicación , Quimioterapia Combinada , Femenino , Furanos , Infecciones por VIH/sangre , Infecciones por VIH/líquido cefalorraquídeo , VIH-1 , Humanos , Concentración 50 Inhibidora , Masculino , Persona de Mediana Edad , Sulfonamidas/administración & dosificación , Sulfonamidas/farmacocinética , Espectrometría de Masas en Tándem
10.
J Antimicrob Chemother ; 66(2): 354-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21098541

RESUMEN

OBJECTIVES: HIV-associated neurocognitive disorders remain common despite use of potent antiretroviral therapy (ART). Ongoing viral replication due to poor distribution of antivirals into the CNS may increase risk for HIV-associated neurocognitive disorders. This study's objective was to determine penetration of a commonly prescribed antiretroviral drug, efavirenz, into CSF. METHODS: CHARTER is an ongoing, North American, multicentre, observational study to determine the effects of ART on HIV-associated neurological disease. Single random plasma and CSF samples were drawn within 1 h of each other from subjects taking efavirenz between September 2003 and July 2007. Samples were assayed by HPLC or HPLC/mass spectrometry with detection limits of 39 ng/mL (plasma) and <0.1 ng/mL (CSF). RESULTS: Eighty participants (age 44 ± 8 years; 79 ± 15 kg; 20 females) had samples drawn 12.5 ± 5.4 h post-dose. The median efavirenz concentrations after a median of 7 months [interquartile range (IQR) 2-17] of therapy were 2145 ng/mL in plasma (IQR 1384-4423) and 13.9 ng/mL in CSF (IQR 4.1-21.2). The CSF/plasma concentration ratio from paired samples drawn within 1 h of each other was 0.005 (IQR 0.0026-0.0076; n = 69). The CSF/IC(50) ratio was 26 (IQR 8-41) using the published IC(50) for wild-type HIV (0.51 ng/mL). Two CSF samples had concentrations below the efavirenz IC(50) for wild-type HIV. CONCLUSIONS: Efavirenz concentrations in the CSF are only 0.5% of plasma concentrations but exceed the wild-type IC(50) in nearly all individuals. Since CSF drug concentrations reflect those in brain interstitial fluids, efavirenz reaches therapeutic concentrations in brain tissue.


Asunto(s)
Fármacos Anti-VIH/líquido cefalorraquídeo , Benzoxazinas/líquido cefalorraquídeo , Infecciones por VIH/líquido cefalorraquídeo , Infecciones por VIH/tratamiento farmacológico , Enfermedades del Sistema Nervioso/líquido cefalorraquídeo , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Adulto , Alquinos , Fármacos Anti-VIH/sangre , Fármacos Anti-VIH/uso terapéutico , Benzoxazinas/sangre , Benzoxazinas/uso terapéutico , Encéfalo , Cromatografía Líquida de Alta Presión , Ciclopropanos , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/virología , Humanos , Concentración 50 Inhibidora , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/virología , Distribución Aleatoria , Carga Viral
12.
Am J Trop Med Hyg ; 101(1): 116-122, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31115303

RESUMEN

Medication adherence is critical to the effectiveness of benznidazole (BZ) therapy for the treatment of Chagas disease. Assessing BZ adherence using traditional plasma sampling methods presents numerous challenges in resource-limited settings. Dried blood spot (DBS) sampling of BZ can be used to overcome logistical barriers and provides a less invasive method for assessing BZ levels. A BZ DBS assay using liquid chromatography-tandem mass spectrometry was developed and applied to a clinical study of infants and children being treated with BZ for Trypanosoma cruzi infection in Argentina. The assay was validated over a concentration range of 9.8-5,000 ng/mL. Inter-assay and intra-assay measures ranged from -2.9% to 2.7% and 0.5% to 8.3% for accuracy and from 3.5% to 12% and 1.6% to 13.6% for precision, respectively. The mean recovery of BZ was greater than 91%. Partitioning ratios for DBSs/plasma ranged from 0.95 to 1.02. A cohort of 10 infants and six children with T. cruzi infection being treated with BZ had median BZ concentrations of 1.2 (IQR 0.29, 2.14) µg/mL with seven of 65 (11%) samples above the BZ treatment goal of 3 µg/mL for adults. The reported DBS assay is a simple and accurate method for the quantitative measurement of BZ that can be applied to facilitate urgently needed clinical studies of BZ for the treatment of Chagas disease and assess BZ adherence in resource-limited settings.


Asunto(s)
Enfermedad de Chagas/sangre , Enfermedad de Chagas/tratamiento farmacológico , Pruebas con Sangre Seca/métodos , Cumplimiento de la Medicación , Nitroimidazoles/sangre , Tripanocidas/sangre , Niño , Preescolar , Cromatografía Liquida , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Espectrometría de Masas , Nitroimidazoles/administración & dosificación , Nitroimidazoles/uso terapéutico , Estudios Prospectivos , Tripanocidas/administración & dosificación , Tripanocidas/uso terapéutico
14.
PLoS One ; 10(7): e0124451, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26132393

RESUMEN

BACKGROUND: Low/ered cholesterol is linked to aggression in some study designs. Cases/series have reported reproducible aggression increases on statins, but statins also bear mechanisms that could reduce aggression. Usual statin effects on aggression have not been characterized. METHODS: 1016 adults (692 men, 324 postmenopausal women) underwent double-blind sex-stratified randomization to placebo, simvastatin 20mg, or pravastatin 40mg (6 months). The Overt-Aggression-Scale-Modified-Aggression-Subscale (OASMa) assessed behavioral aggression. A significant sex-statin interaction was deemed to dictate sex-stratified analysis. Exploratory analyses assessed the influence of baseline-aggression, testosterone-change (men), sleep and age. RESULTS: The sex-statin interaction was significant (P=0.008). In men, statins tended to decrease aggression, significantly so on pravastatin: difference=-1.0(SE=0.49)P=0.038. Three marked outliers (OASMa-change ≥40 points) offset otherwise strong significance-vs-placebo: statins:-1.3(SE=0.38)P=0.0007; simvastatin:-1.4(SE=0.43)P=0.0011; pravastatin:-1.2(SE=0.45)P=0.0083. Age≤40 predicted greater aggression-decline on statins: difference=-1.4(SE=0.64)P=0.026. Aggression-protection was emphasized in those with low baseline aggression: age<40-and-low-baseline-aggression (N=40) statin-difference-vs-placebo=-2.4(SE=0.71)P=0.0016. Statins (especially simvastatin) lowered testosterone, and increased sleep problems. Testosterone-drop on statins predicted aggression-decline: ß=0.64(SE=0.30)P=0.034, particularly on simvastatin: ß=1.29(SE=0.49)P=0.009. Sleep-worsening on statins significantly predicted aggression-increase: ß=2.2(SE=0.55)P<0.001, particularly on simvastatin (potentially explaining two of the outliers): ß=3.3(SE=0.83)P<0.001. Among (postmenopausal) women, a borderline aggression-increase on statins became significant with exclusion of one younger, surgically-menopausal woman (N=310) ß=0.70(SE=0.34)P=0.039. The increase was significant, without exclusions, for women of more typical postmenopausal age (≥45): (N=304) ß=0.68(SE=0.34)P=0.048 - retaining significance with modified age-cutoffs (≥50 or ≥55). Significance was observed separately for simvastatin. The aggression-increase in women on statins was stronger in those with low baseline aggression (N=175) ß=0.84(SE=0.30)P=0.006. No statin effect on whole blood serotonin was observed; and serotonin-change did not predict aggression-change. CONCLUSION: Statin effects on aggression differed by sex and age: Statins generally decreased aggression in men; and generally increased aggression in women. Both findings were selectively prominent in participants with low baseline aggression - bearing lower change-variance, rendering an effect more readily evident. TRIAL REGISTRATION: Clinicaltrials.gov NCT00330980.


Asunto(s)
Agresión/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Adulto , Factores de Edad , Anciano , Femenino , Estudios de Seguimiento , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Masculino , Persona de Mediana Edad , Serotonina/sangre , Factores Sexuales , Trastornos del Sueño-Vigilia , Testosterona/sangre , Resultado del Tratamiento
15.
Toxicol Sci ; 71(2): 263-75, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12563112

RESUMEN

To define the effects of chronic spinal exposure to a highly selective partial differential opioid agonist c[DPen(2),DPen(5)]enkephalin (DPDPE), adult beagles were prepared with chronic lumbar intrathecal catheters. Groups of dogs received intrathecal infusions (100 micro l/h) of saline (vehicle), DPDPE 3 mg/ml or 6 mg/ml for 28 days. Over the 28-day period, saline or 3 mg/ml showed minimal changes in neurological function, whereas in the 6 mg/ml animals, prominent hind limb dysfunction evolved over the 28-day interval. Histopathology in control animals displayed a modest pericatheter reaction considered normal for this model. Dogs receiving DPDPE (three of four at 6 mg/ml and one of four at 3 mg/ml) but not saline (zero of four) developed large inflammatory masses (granulomas) in the intrathecal space located proximal to the catheter tip. In these masses, severe chronic inflammatory changes in combination with necrosis and fibrosis was detected. Occasional focal destruction of neuropil was detected also in the adjacent spinal cord parenchyma. These masses contained extensive accumulation of mouse antihuman macrophages (MAC)-positive inflammatory cells expressing tumor necrosis factor-alpha (TNF-alpha), revealing infiltration of macrophages, granulocytes, and monocytes. In separate animals, prepared with dual intrathecal catheters, lumbar CSF was sampled at specified time points following intrathecal bolus (3 mg/ml) and 24 h DPDPE infusion (3 mg/ml and 6 mg/ml). Steady-state cerebrospinal fluid (CSF) DPDPE levels were 18.6 +/- 1.0 and 22.6 +/- 4.0 micro g/ml for 3 mg/ml and 6 mg/ml infusions respectively. These results indicate that this partial differential opioid agonist DPDPE produces a concentration and time-dependent formation of an intrathecal inflammatory mass.


Asunto(s)
Analgésicos Opioides/toxicidad , Conducta Animal/efectos de los fármacos , Encefalina D-Penicilamina (2,5)/toxicidad , Granuloma/inducido químicamente , Enfermedades de la Médula Espinal/inducido químicamente , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/farmacocinética , Animales , Área Bajo la Curva , Catéteres de Permanencia , Perros , Relación Dosis-Respuesta a Droga , Encefalina D-Penicilamina (2,5)/administración & dosificación , Encefalina D-Penicilamina (2,5)/farmacocinética , Femenino , Granuloma/patología , Inyecciones Espinales , Masculino , Actividad Motora/efectos de los fármacos , Médula Espinal/efectos de los fármacos , Médula Espinal/patología , Enfermedades de la Médula Espinal/patología
16.
Artículo en Inglés | MEDLINE | ID: mdl-12016017

RESUMEN

An atmospheric pressure ionization liquid chromatographic-mass spectrometric assay was developed and validated for the determination of D-penicillamine(2,5) enkephalin (DPDPE) in cerebrospinal fluid (CSF) from dog. DPDPE and internal standard (D-Ala(2),D-Leu(5) enkephalin=DADLE) were isolated from CSF by reversed-phase C(18) solid-phase extraction with ZipTip micro-cartridges. Aliquots of extracted eluate were injected onto an Agilent Zorbax SB C(18) column (30 x 2.2 mm; 3.5 microm) at a flow-rate of 0.4 ml/min. The isocratic mobile phase of methanol-10 mM ammonium formate (pH 3) (75:25, v/v) was then diverted to waste for 45 s after injection, after which time flow was directed to the single quadrupole mass spectrometer. DPDPE was detected by positive mode selected ion monitoring. Standard curves were linear (r(2)> or =0.991) over the concentration range 1-1000 ng/ml. The efficiency of extraction recovery was greater than 97%, and the intra-assay and inter-assay precisions were within 9% relative standard deviation. DPDPE and the internal standard were stable in the injection solvent at 4 degrees C for at least 48 h. The assay was applied to the pharmacokinetic study of intrathecal DPDPE administration in the dog animal model.


Asunto(s)
Analgésicos Opioides/líquido cefalorraquídeo , Cromatografía Líquida de Alta Presión/métodos , Encefalina D-Penicilamina (2,5)/líquido cefalorraquídeo , Espectrometría de Masas/métodos , Analgésicos Opioides/farmacocinética , Animales , Perros , Encefalina D-Penicilamina (2,5)/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
J Pharm Biomed Anal ; 31(2): 243-50, 2003 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-12609663

RESUMEN

A facile and sensitive method utilizing solid-phase cartridge extraction and capillary gas chromatography (GC) with nitrogen phosphorus detection was validated for the determination of MK-801 [(+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cyclo-hepten-5,10-imine maleate], a non-competitive NMDA receptor antagonist, in dog cerebrospinal fluid (CSF) and plasma. Clonidine hydrochloride was used as the internal standard (ISTD), after evaluation of several ISTD candidates. Separations were performed with an intermediate polarity fused silica capillary column, yielding typical retention times of 3.20 min for MK-801 and 4.90 min for ISTD. Plasma and CSF samples were extracted with 100 mg Bond Elut C(18) TCA Copyright cartridges to yield methanolic eluates that were evaporatively enriched before reconstitution in anhydrous ethanol prior to injection. The standard curve was validated from 1 to 100,000 ng/ml for CSF, and from 0.1 to 1,000 ng/ml for plasma. Chromatograms from naive plasma and CSF exhibited no endogenous interfering peaks. The efficiency of extraction recovery was >94%, and the intra-assay and inter-assay precision was within 9% relative standard deviation (%R.S.D.) for both fluids. MK-801 and ISTD were stable in the injection solvent at 22 degrees C for at least 48 h. The assay was applied to the toxocologic study of intrathecal MK-801 administration in the dog.


Asunto(s)
Cromatografía de Gases/métodos , Maleato de Dizocilpina/análisis , Antagonistas de Aminoácidos Excitadores/análisis , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Animales , Calibración , Maleato de Dizocilpina/sangre , Maleato de Dizocilpina/líquido cefalorraquídeo , Perros , Antagonistas de Aminoácidos Excitadores/sangre , Antagonistas de Aminoácidos Excitadores/líquido cefalorraquídeo , Nitrógeno , Fósforo , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
J Addict Med ; 7(2): 113-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23370932

RESUMEN

BACKGROUND: Oral morphine is a recommended option for the treatment of neonatal abstinence syndrome (NAS). Commercially available oral morphine solution products in the United States are not formulated in concentrations appropriate for use in neonates. OBJECTIVE: To test the stability of a diluted oral morphine solution for treatment of NAS. METHODS: Ethanol-free morphine 2 mg/mL oral solution was diluted to 0.4 mg/mL with sterile water and stored in a light protected container at room temperature (20°C-25°C). The change in morphine concentration over time was measured by liquid chromatography mass spectrometry with simultaneous ultraviolet diode array detection. RESULTS: : The test morphine solution retained 107% of its original concentration after 60 days. CONCLUSION: Extemporaneously prepared 0.4 mg/mL oral morphine solution is suitable for use in the treatment of NAS as a potentially safer alternative to opium-containing agents.


Asunto(s)
Estabilidad de Medicamentos , Morfina/química , Narcóticos/química , Síndrome de Abstinencia Neonatal , Administración Oral , Cromatografía Líquida de Alta Presión/métodos , Composición de Medicamentos/métodos , Almacenaje de Medicamentos , Humanos , Recién Nacido , Soluciones Farmacéuticas , Estados Unidos
19.
Org Lett ; 15(9): 2314-7, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23611591

RESUMEN

For the first time, a general catalytic procedure for the cross-coupling of primary amides and alkylboronic acids is demonstrated. The key to the success of this reaction was the identification of a mild base (NaOSiMe3) and oxidant (di-tert-butyl peroxide) to promote the copper-catalyzed reaction in high yield. This transformation provides a facile, high-yielding method for the monoalkylation of amides.


Asunto(s)
Amidas/síntesis química , Ácidos Borónicos/química , Cobre/química , Oxidantes/química , Peróxidos/química , Amidas/química , Catálisis
20.
Antivir Ther ; 18(4): 585-90, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23183881

RESUMEN

BACKGROUND: Pharmacokinetic data for lopinavir in late pregnancy and in breastfeeding are limited, and no data for abacavir in breast milk are available. METHODS: Women in the Mma Bana Study initiated HAART from 18 to 34 weeks of gestation. We determined trough plasma and whole breast milk concentrations of lopinavir (LPV), abacavir (ABC), nevirapine (NVP), lamivudine (3TC) and zidovudine (ZDV) among separate subsets of pregnant and breastfeeding women, and in plasma of exposed infants. Lopinavir was measured 1 month after starting HAART or 1 month postpartum, and other drugs were measured 1 month postpartum. RESULTS: Sampling occurred a median of 14 h (range 11-17) from last maternal drug ingestion. Although 50% higher median LPV levels were seen in postpartum than antepartum plasma (8.29 µg/ml versus 5.51 µg/ml; P = 0.02), antepartum levels with standard LPV dosing were therapeutic for all women (> 1.0 µg/ml). Very low LPV levels (< 0.25 µg/ml) were detected in breast milk. Median ABC levels in breast milk were 85% of those in plasma (0.057 µg/ml versus 0.067 µg/ml). Breast milk concentrations of NVP and 3TC were 27% and 74% of plasma levels, respectively. At these trough maternal time points, only NVP was detectable in potentially inhibitory levels in breastfeeding infants, and most infants had non-detectable levels of LPV, ABC, ZDV and 3TC via maternal breast milk. CONCLUSIONS: Standard LPV dosing achieved therapeutic levels in pregnancy and no appreciable concentrations in breast milk. ABC is detectable in breast milk at similar concentrations to plasma, but does not result in appreciable infant exposure.


Asunto(s)
Fármacos Anti-VIH/farmacocinética , Didesoxinucleósidos/farmacocinética , Infecciones por VIH/sangre , Lamivudine/farmacocinética , Lopinavir/farmacocinética , Leche Humana/química , Adulto , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Botswana , Lactancia Materna , Didesoxinucleósidos/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Lactante , Lactancia , Lamivudine/uso terapéutico , Lopinavir/uso terapéutico , Persona de Mediana Edad , Nevirapina/farmacocinética , Nevirapina/uso terapéutico , Embarazo , Complicaciones Infecciosas del Embarazo , Carga Viral/efectos de los fármacos , Zidovudina/farmacocinética , Zidovudina/uso terapéutico
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