RESUMEN
Recently, lidocaine topical systems utilizing nonaqueous matrices have been developed and provide efficient lidocaine delivery through the skin, such that lower concentrations of drug provide equivalent or greater drug delivery than drug-in-matrix hydrogel lidocaine patches. This study characterizes drug delivery from a nonaqueous lidocaine topical system with increasing drug load both in vitro and in vivo. Topical systems formulated with either 1.8% or 5.4% lidocaine were applied to healthy volunteers' backs (n = 15) for 12 h in a single-center, open-label, four-treatment, four-period crossover pharmacokinetic study. Subjects were dosed with either three 1.8% systems or one, two, or three 5.4% systems in each period. Blood was collected for up to 48 h, and plasma lidocaine levels were measured with a validated HPLC method. In parallel, human and mouse skin models characterized the in vitro skin permeation profile. The pharmacokinetic profile was linear between one, two, and three lidocaine 5.4% applications. Application of three lidocaine 1.8% systems (108 mg lidocaine) was bioequivalent to one lidocaine 5.4% system (108 mg lidocaine). Both topical systems remained well adhered to the skin and irritation was mild. The 5.4% system had approximately threefold higher skin permeability than the 1.8% system in the mouse and human skin models. The results indicate increasing the drug load by three times results in triple the drug delivery both in vivo and in vitro. The relationship between the in vitro permeation and in vivo absorption correlates and is nonlinear.
Asunto(s)
Lidocaína , Preparaciones Farmacéuticas , Administración Cutánea , Animales , Femenino , Lidocaína/metabolismo , Masculino , Ratones , Permeabilidad , Preparaciones Farmacéuticas/metabolismo , Piel/metabolismo , Absorción CutáneaRESUMEN
OBJECTIVE: Antidepressants have been recommended for the treatment of post-stroke depression (PSD). The purpose of this study was to evaluate the effect of fluvoxamine maleate, a selective serotonin re-uptake inhibitor (SSRI), on depressive state, sleep disturbance, and serum melatonin levels in patients with depressive state after cerebral infarction. METHODS: Nineteen patients who were hospitalized for cerebral infarction and scored 40 points or higher on the Self Depression Scale (SDS) were enrolled in this study. Nine of the 19 patients received fluvoxamine as a treatment group and the other 10 patients were used as untreated controls. Before and after commencing the drug therapy, the patients were assessed by the SDS, Pittsburgh Sleep Quality Index (PSQI), Japan Stroke Scale for Depression (JSSD), and Japan Stroke Scale for Emotional Disturbance (JSSE), and their serum melatonin levels were measured. The control group underwent the same evaluations as the treatment group. RESULTS: The SDS score improved in the treatment group at 1 week after the start of drug treatment, and in the control group at 1 and 2 weeks into the observation period. In the treatment group, the JSSD and PSQI scores improved and serum melatonin levels increased. CONCLUSION: The administration of fluvoxamine to patients with depressive state after cerebral infarction alleviated both the depressive state and sleep disturbances. Increased melatonin levels by the administration of fluvoxamine may contribute to improvement in sleep disturbance, one of the major symptoms of depression.
Asunto(s)
Infarto Cerebral/complicaciones , Depresión/tratamiento farmacológico , Fluvoxamina/uso terapéutico , Melatonina/sangre , Anciano , Anciano de 80 o más Años , Antidepresivos de Segunda Generación/uso terapéutico , Infarto Cerebral/sangre , Depresión/sangre , Depresión/etiología , Femenino , Humanos , Masculino , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Trastornos del Sueño-Vigilia/sangre , Trastornos del Sueño-Vigilia/tratamiento farmacológico , Trastornos del Sueño-Vigilia/etiología , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/complicacionesRESUMEN
BACKGROUND: Glutathione transferase (GST) catalyzes glutathione conjugation, a major detoxification pathway for xenobiotics and endogenous substances. Here, we determined the crystal structure of a Delta-class GST from Bombyx mori (bmGSTD) to examine its catalytic residues. METHODS: The three-dimensional structure of bmGSTD was resolved by the molecular replacement method and refined to a resolution of 2.0Å. RESULTS: Structural alignment with a Delta-class GST of Anopheles gambiae indicated that bmGSTD contains 2 distinct domains (an N-terminal domain and a C-terminal domain) connected by a linker. The bound glutathione localized at the N-terminal domain. Putative catalytic residues were changed to alanine by site-directed mutagenesis, and the resulting mutants were characterized in terms of catalytic activity using glutathione and 1-chloro-2,4-dinitrobenzene, a synthetic substrate of GST. Kinetic analysis of bmGSTD mutants indicated that Ser11, Gln51, His52, Ser67, and Arg68 are important for enzyme function. GENERAL SIGNIFICANCE: These results provide structural insights into the catalysis of glutathione conjugation in B. mori by bmGSTD.
Asunto(s)
Bombyx/enzimología , Glutatión Transferasa/química , Glutatión Transferasa/metabolismo , Secuencia de Aminoácidos , Animales , Bombyx/genética , Catálisis , Dominio Catalítico/genética , Cristalización , Activación Enzimática , Estabilidad de Enzimas/genética , Glutatión Transferasa/clasificación , Glutatión Transferasa/genética , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Dominios y Motivos de Interacción de Proteínas/genética , Homología de Secuencia de Aminoácido , Relación Estructura-ActividadRESUMEN
BACKGROUND: Glutathione transferase (GST) catalyzes a major step in the xenobiotic detoxification pathway. We previously identified a novel, unclassified GST that is upregulated in an insecticide-resistant silkworm (Bombyx mori) upon insecticide exposure. Here, we sought to further characterize this GST, bmGSTu, by solving and refining its crystal structure and identifying its catalytic residues. METHODS: The structure of wild-type bmGSTu was determined with a resolution of 2.1Å by synchrotron radiation and molecular modeling. Potential catalytic residues were mutated to alanine by means of site-directed mutagenesis, and kinetic data determined for wild-type and mutated bmGSTu. RESULTS: We found that bmGSTu occurred as a dimer, and that, like other GSTs, each subunit displayed a G-site and an H-site in the active center. Bound glutathione could be localized at the G-site. Kinetic data of the mutated forms of bmGSTu show that Val55, Glu67, and Ser68 in the G-site are important for catalysis. Furthermore, the H-site showed some unique features. CONCLUSIONS: This is the first study to our knowledge to elucidate the molecular conformation of this B. mori GST. Our results indicate that residues Val55, Glu67, and Ser68, as well as Tyr7 and Ser12, in the glutathione-binding region of bmGSTu are critical for catalytic function. GENERAL SIGNIFICANCE: Our results, together with our previous finding that bmGSTu was preferentially induced in an insecticide-resistant strain, support the idea that bmGSTu functions in the transformation of exogenous chemical agents. Furthermore, the unique features observed in bmGSTu may shed light on mechanisms of insecticide resistance.
Asunto(s)
Bombyx/enzimología , Glutatión Transferasa/química , Secuencia de Aminoácidos , Animales , Biocatálisis , Dominio Catalítico , Cristalografía por Rayos X , Glutatión Transferasa/metabolismo , Cinética , Modelos Moleculares , Datos de Secuencia Molecular , Homología de Secuencia de AminoácidoRESUMEN
alpha(1)-Adrenoceptor antagonists are useful antihypertensive agents for patients with hypertension who have hyperlipidemia, benign prostatic hyperplasia, or pheochromocytoma. The purpose of this study was to evaluate the effect of the alpha(1)-adrenoceptor antagonist, doxazosin mesilate, on cerebral blood flow (CBF) and flow velocity in the common carotid artery in patients with hypertension and chronic cerebral infarction. Doxazosin mesilate (1 mg/day) was orally administered for 4 to 8 weeks to 7 patients with hypertension 4 weeks after the onset of cerebral infarction. We determined blood pressure, heart rate, CBF measured with autoradiography single photon emission computed tomography (SPECT) with N-isopropyl-p-[(123)I] iodoamphetamine ((123)I-IMP) as a tracer, and the maximum, minimum and mean flow velocities in the common carotid arteries measured with duplex carotid ultrasonography before and 4 to 8 weeks after the beginning of treatment. Mean CBF was defined as the mean count of tracer from the 8 regions of interest (ROIs) in the frontal, parietal, occipital, and temporal cortices of the cerebral hemisphere. Values were analyzed with paired t tests. With administration of doxazosin mesilate, systolic pressure significantly decreased from 152 +/- 11 to 137 +/- 7 mmHg (p<0.01), but diastolic pressure and heart rate were unchanged. Mean CBF was improved significantly from 32.0 +/- 4.1 to 34.7 +/- 4.1 mL/100 g brain/min (p<0.01) in the ipsilateral cerebral cortex and from 32.6 +/- 6.2 to 36.2 +/- 5.1 mL/100 g brain/min (p<0.05) in the contralateral cerebral cortex. The maximum, minimum, and mean flow velocities in the bilateral common carotid arteries were not changed significantly. In the present study, the improvement of mean CBF in the ipsilateral and contralateral cerebral cortices was demonstrated in patients with hypertension and chronic cerebral infarction after the treatment with doxazosin mesilate. Doxazosin mesilate might be an effective antihypertensive agent for hypertensive chronic cerebral infarction.
Asunto(s)
Antagonistas Adrenérgicos alfa/uso terapéutico , Antihipertensivos/uso terapéutico , Arteria Carótida Común/efectos de los fármacos , Infarto Cerebral/tratamiento farmacológico , Circulación Cerebrovascular/efectos de los fármacos , Doxazosina/uso terapéutico , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Anciano , Velocidad del Flujo Sanguíneo , Presión Sanguínea/efectos de los fármacos , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Común/fisiopatología , Infarto Cerebral/complicaciones , Infarto Cerebral/fisiopatología , Enfermedad Crónica , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Tomografía Computarizada de Emisión de Fotón Único , Resultado del Tratamiento , Ultrasonografía Doppler en ColorRESUMEN
Otitis media chronica cholesteatomatica with cerebral sigmoid sinus thrombosis is an important differential diagnosis in the evaluation of headache. We describe a 31-year-old Filipino man with chief complaints of headache, otalgia, vomiting, and vertigo, and no significant past medical history. Two years before admission he stuffed tissues into the right external auditory canal because of a noise in the street on the night of the New Years festival and sometimes had right ear discharge. One month before admission he had a right occipital headache with right otalgia and fever. One day before admission he vomited. Vertigo developed on the day of admission. On physical examination at admission, the patient was somnolent and had a body temperature of 36.9 degrees C, and meningeal signs were obvious. Magnetic resonance of the brain revealed right otitis media chronica cholesteatomatica and right cerebral sigmoid sinus thrombosis. Computed tomography of the skull base revealed that the tympanic cavity and mastoid air cells were filled with a mass of soft-tissue density invading toward the sigmoid sinus. Cerebrospinal fluid examination showed a cell count of 32/3 mm3. The patients level of consciousness and symptoms improved after administration of ampicillin and ceftriaxone sodium. A diagnosis of "headache attributed to disorder of ears," with The International Classification of Headache Disorders, 2nd edition (ICHD-II) code 11.4, was made on the basis of symptoms and imaging findings. Otitis media chronica cholesteatomatica had invaded toward the sigmoid sinus and was thought to be the cause of cerebral sigmoid sinus thrombosis and meningitis. Six weeks after admission the patient underwent mastoidectomy and tympanoplasty to cure the cholesteatoma and prevent recurrence of inflammation. The postoperative progress was satisfactory. In cases of headache with otalgia, "headache attributed to disorder of ears" should be considered.
Asunto(s)
Colesteatoma del Oído Medio/complicaciones , Cefalea/etiología , Trombosis Intracraneal/complicaciones , Otitis Media/complicaciones , Adulto , Enfermedad Crónica , Humanos , MasculinoRESUMEN
The frequency of post-stroke depression (PSD) was evaluated in an ischemic stroke cohort four weeks after onset, and the relationship between self-rating depression scale (SDS)/and infarct size, number and location of the ischemic brain lesions was also studied. The effects of a newly developed antidepressant SSRI (selective serotonin reuptake inhibitor), fluvoxamine maleate, on PSD and cerebral blood flow (CBF) was investigated in other ischemic stroke patients. The frequency of patients who had more than 40 on SDS score was 46% (18/39), and that of patients who had more than 50 was 13% (5/39). There were no differences in SDS score in infarct size, number and location of ischemic brain lesions, however there were significant differences in the lesion side. The score of the patients who had lesions in the left hemisphere was significantly higher than that of those who had them in the right. Administration of fluvoxamine maleate for four weeks improved the score on the Hamilton rating scale for depression (HAM-D) from 16.6 +/- 4.7 (n = 5) to 8.4 +/- 4.3 (n = 5), however it did not influence the mean cortical CBF. This study shows that the patients frequently had depression after ischemic stroke, and that left side lesion had a significant relationship with PSD. Therefore it is important that psychiatric examination of post-stroke patients is conducted. This study also shows that a newly developed antidepressant, fluvoxamine maleate, was effective for PSD.