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1.
Public Health ; 198: 238-244, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34487867

RESUMO

OBJECTIVES: During the COVID-19 pandemic, ethnic minorities have been more susceptible to infection and demonstrated poorer outcomes. This study describes COVID-19 morbidity and mortality by ethnic group, represented by Arab and Jewish localities in Israel, during the different waves of the outbreak and addresses sociocultural aspects of the pandemic. STUDY DESIGN: A retrospective national archive study was conducted in Israel. METHODS: Data were obtained from the Ministry of Health's database, including daily information on Arab, Jewish or mixed localities, from February 2020 to February 2021. RESULTS: During the first wave of the pandemic, the incidence of COVID-19 in Arab compared with Jewish localities was 67% lower and mortality was 85% lower, in addition to lower rates of severe disease requiring hospitalisation. During the second and third waves, these trends reversed, with the proportion of positive tests, incidence and mortality in Arab localities reaching and then surpassing rates in Jewish localities. By September 2020, COVID-19 mortality was twice as high in Arab compared with Jewish localities. CONCLUSIONS: After low morbidity during the first wave of the COVID-19 pandemic, a surge in infections occurred in the Arab population during subsequent waves, to match and surpass the high incidence seen in the Jewish population. This unique pattern highlights the changing experiences of a minority group as the pandemic progressed and demonstrates how COVID-19 exacerbates existing disparities.


Assuntos
COVID-19 , Pandemias , Árabes , Humanos , Israel/epidemiologia , Judeus , Grupos Minoritários , Morbidade , Estudos Retrospectivos , SARS-CoV-2
2.
J Prev Alzheimers Dis ; 4(1): 44-50, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29188859

RESUMO

OBJECTIVES: We examined whether multiple domains of baseline cognitive performance were associated with prospective physical activity (PA) adherence in the Lifestyle Interventions and Independence for Elders Pilot study (LIFE-P). DESIGN, SETTING, PARTICIPANTS: The LIFE-P study was a single-blind, multicenter, randomized controlled trial of a PA intervention compared to a successful aging educational intervention in sedentary, mobility-limited older adults. INTERVENTION: A 12-month structured, moderate-intensity, multi-modal PA program that included walking, resistance training, and flexibility exercises. For the first 2 months (adoption), 3 center-based exercise sessions (40-60 min) / week were conducted. During the next 4 months (transition), center-based sessions were conducted 2 times / week. The subsequent maintenance phase consisted of optional once-to-twice-per-week center-based sessions and home-based PA. MEASUREMENTS: Tests of executive and global cognitive functioning, working memory and psychomotor speed were administered at baseline. Median test scores were used to dichotomize participants into low or high cognitive performance groups. RESULTS: 52 mobility-limited older adults (age: 76.9 ±5 yrs) were randomized to the PA arm of LIFE-P. Compared to participants with high cognitive performance, participants with low performance had similar PA adherence rates (all P ≥ 0.34). Furthermore, weak and non-significant univariate relationships were elicited between all measures of cognition and overall PA adherence levels (r values ranged: -0.20 to 0.12, P ≥ 0.12). CONCLUSION: These data suggest that cognitive performance does not limit long-term PA adherence in mobility-limited older adults. Additional studies in larger cohorts are warranted to verify these findings.


Assuntos
Cognição , Disfunção Cognitiva , Terapia por Exercício/psicologia , Exercício Físico , Cooperação do Paciente/psicologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Educação em Saúde , Humanos , Masculino , Memória de Curto Prazo , Limitação da Mobilidade , Testes Neuropsicológicos , Projetos Piloto , Comportamento Sedentário , Método Simples-Cego
3.
J Frailty Aging ; 5(1): 6-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26980363

RESUMO

BACKGROUND: Converging evidence suggests that physical activity is an effective intervention for both clinical depression and sub-threshold depressive symptoms; however, findings are not always consistent. These mixed results might reflect heterogeneity in response to physical activity, with some subgroups of individuals responding positively, but not others. OBJECTIVES: 1) To examine the impact of genetic variation and sex on changes in depressive symptoms in older adults after a physical activity (PA) intervention, and 2) to determine if PA differentially improves particular symptom dimensions of depression. DESIGN: Randomized controlled trial. SETTING: Four field centers (Cooper Institute, Stanford University, University of Pittsburgh, and Wake Forest University). PARTICIPANTS: 396 community-dwelling adults aged 70-89 years who participated in the Lifestyle Interventions and Independence for Elders Pilot Study (LIFE-P). INTERVENTION: 12-month PA intervention compared to an education control. MEASUREMENTS: Polymorphisms in the serotonin transporter (5-HTT), brain-derived neurotrophic factor (BDNF), and apolipoprotein E (APOE) genes; 12-month change in the Center for Epidemiologic Studies Depression Scale total score, as well as scores on the depressed affect, somatic symptoms, and lack of positive affect subscales. RESULTS: Men randomized to the PA arm showed the greatest decreases in somatic symptoms, with a preferential benefit in male carriers of the BDNF Met allele. Symptoms of lack of positive affect decreased more in men compared to women, particularly in those possessing the 5-HTT L allele, but the effect did not differ by intervention arm. APOE status did not affect change in depressive symptoms. CONCLUSIONS: Results of this study suggest that the impact of PA on depressive symptoms varies by genotype and sex, and that PA may mitigate somatic symptoms of depression more than other symptoms. The results suggest that a targeted approach to recommending PA therapy for treatment of depression is viable.


Assuntos
Apolipoproteínas E/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Depressão , Terapia por Exercício/métodos , Estilo de Vida , Atividade Motora , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Idoso , Idoso de 80 Anos ou mais , Depressão/diagnóstico , Depressão/genética , Depressão/fisiopatologia , Depressão/terapia , Feminino , Humanos , Vida Independente/psicologia , Masculino , Atividade Motora/genética , Atividade Motora/fisiologia , Polimorfismo Genético , Escalas de Graduação Psiquiátrica , Fatores Sexuais , Resultado do Tratamento
4.
Clin Obes ; 5(6): 342-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26486256

RESUMO

This paper examined the psychosocial predictors of weight loss among race and sex subgroups. Analyses included overweight and obese participants from the PREMIER study, a previously published randomized trial that examined the effects of two multi-component lifestyle interventions on blood pressure among pre-hypertensive and stage 1 hypertensive adults. Both intervention conditions received behavioural recommendations for weight loss and group sessions. Weight and psychosocial measures of self-efficacy and social support for diet and exercise were assessed at baseline and at 6 months. There were 157 African-American (AA) women, 46 AA men, 203 non-AA women and 182 non-AA men with an average age of 50 years and average body mass index of 34 at baseline. Multiple predictor regression models were performed individually by race and sex subgroup. Among AA women, increases in diet self-efficacy were associated with weight loss. Among AA men, increases in diet-related social support and self-efficacy, along with increases in family support to exercise, were associated with weight loss (all Ps <0.05). Among non-AA women, increases in friends' support to exercise and exercise-related self-efficacy were associated with weight loss, and among non-AA men only increases in diet self-efficacy were associated with weight loss (all Ps <0.05). These results emphasize the need for targeted interventions based on race and sex to optimize the impact of lifestyle-based weight loss programmes.


Assuntos
Dietoterapia , Exercício Físico , Comportamentos Relacionados com a Saúde/etnologia , Grupos Raciais/psicologia , Autoeficácia , Apoio Social , Redução de Peso/etnologia , Adulto , Negro ou Afro-Americano/psicologia , Pressão Sanguínea , Feminino , Humanos , Hipertensão/terapia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Obesidade/psicologia , Sobrepeso/psicologia , Fatores Sexuais , Estados Unidos , População Branca/psicologia
5.
AJNR Am J Neuroradiol ; 35(12): 2388-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24852291

RESUMO

BACKGROUND AND PURPOSE: Brain MR imaging is recommended in children with cerebral palsy. Descriptions of MR imaging findings lack uniformity, due to the absence of a validated quantitative approach. We developed a quantitative scoring method for brain injury based on anatomic MR imaging and examined the reliability and validity in correlation to motor function in children with hemiplegia. MATERIALS AND METHODS: Twenty-seven children with hemiplegia underwent MR imaging (T1, T2-weighted sequences, DTI) and motor assessment (Manual Ability Classification System, Gross Motor Functional Classification System, Assisting Hand Assessment, Jebsen Taylor Test of Hand Function, and Children's Hand Experience Questionnaire). A scoring system devised in our center was applied to all scans. Radiologic score covered 4 domains: number of affected lobes, volume and type of white matter injury, extent of gray matter damage, and major white matter tract injury. Inter- and intrarater reliability was evaluated and the relationship between radiologic score and motor assessments determined. RESULTS: Mean total radiologic score was 11.3 ± 4.5 (range 4-18). Good inter- (ρ = 0.909, P < .001) and intrarater (ρ = 0.926, P = < .001) reliability was demonstrated. Radiologic score correlated significantly with manual ability classification systems (ρ = 0.708, P < .001), and with motor assessments (assisting hand assessment [ρ = -0.753, P < .001]; Jebsen Taylor test of hand function [ρ = 0. 766, P < .001]; children's hand experience questionnaire [ρ = -0. 716, P < .001]), as well as with DTI parameters. CONCLUSIONS: We present a novel MR imaging-based scoring system that demonstrated high inter- and intrarater reliability and significant associations with manual ability classification systems and motor evaluations. This score provides a standardized radiologic assessment of brain injury extent in hemiplegic patients with predominantly unilateral injury, allowing comparison between groups, and providing an additional tool for counseling families.


Assuntos
Lesões Encefálicas/classificação , Lesões Encefálicas/diagnóstico , Hemiplegia/classificação , Hemiplegia/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adolescente , Criança , Feminino , Humanos , Masculino , Exame Neurológico
6.
Ann Behav Med ; 46(3): 369-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23813320

RESUMO

BACKGROUND: The Weight Loss Maintenance Trial tested strategies for maintenance of weight loss. Personal contact was superior to interactive technology and self-directed conditions. PURPOSE: We aimed to identify behavioral mediators of the superior effect of personal contact vs. interactive technology and of personal contact vs. self-directed arms. METHODS: Overweight/obese adults at risk for cardiovascular disease (n = 1,032) who lost at least 4 kg were randomized to personal contact, interactive technology, or self-directed. After 30 months, 880 participants had data on weight and behavioral strategies. RESULTS: Reported increase of intake of fruits and vegetables and physical activity and more frequent self-weighing met criteria as mediators of the better outcome of personal contact vs. interactive technology. Increased intake of fruits and vegetables, more frequent self-weighing, and decreased dessert consumption were mediators of the difference between personal contact vs. self-directed. CONCLUSION: Inducing changes in the identified behaviors might yield better outcomes in future weight loss maintenance trials.


Assuntos
Obesidade/psicologia , Obesidade/terapia , Sobrepeso/psicologia , Sobrepeso/terapia , Programas de Redução de Peso , Aconselhamento , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Autocuidado/psicologia , Terapia Assistida por Computador , Resultado do Tratamento
7.
Langmuir ; 28(2): 1596-603, 2012 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-22221003

RESUMO

In situ electrochemical extended X-ray absorption fine structure (EXAFS) was used to evaluate the structure of Pt dendrimer-encapsulated nanoparticles (DENs) during the oxygen reduction reaction (ORR). The DENs contained an average of just 225 atoms each. The results indicate that the Pt coordination number (CN) decreases when the electrode potential is moved to positive values. The results are interpreted in terms of an ordered core, disordered shell model. The structure of the DENs is not significantly impacted by the presence of dioxygen, but other electrogenerated species may have a significant impact on nanoparticle structure.

8.
Chemphyschem ; 11(13): 2942-50, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20715278

RESUMO

We report an in situ X-ray absorption-fine structure (XAFS) spectroscopic analysis of ∼1.8 nm Pt dendrimer-encapsulated nanoparticles (DENs) during electrocatalytic oxidation of CO. The results indicate that Pt nanoparticles encapsulated within poly(amidoamine) (PAMAM) dendrimers and immobilized on a carbon electrode retain their electrocatalytic activity and are structurally stable for extended periods during CO oxidation. This is a significant finding, because nanoparticles in this size range are good experimental models for comparison to first-principles calculations if they remain stable.


Assuntos
Monóxido de Carbono/química , Nanopartículas Metálicas/química , Platina/química , Poliaminas/química , Carbono/química , Dendrímeros/química , Eletroquímica , Eletrodos , Oxirredução , Propriedades de Superfície , Espectroscopia por Absorção de Raios X
9.
Langmuir ; 26(15): 12994-9, 2010 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-20590140

RESUMO

We report the synthesis and characterization of NiSn dendrimer-encapsulated nanoparticles (DENs) with sizes in the range of approximately 1.2 nm. These types of materials have potential applications in energy storage, and particles in the 1-3 nm size range are particularly attractive for this use. The NiSn DENs described here contain an average of 147 atoms and are encapsulated within hydrophobic, sixth-generation poly(amidoamine) dendrimers. DENs prepared using four different Ni/Sn ratios, along with monometallic Ni and Sn DENs, are described. To prevent oxidation, the synthesis was carried out under dry conditions in toluene. These bimetallic DENs were characterized by UV-vis spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The results indicate that the compositions of the nanoparticles reflect the ratio of Ni(2+) and Sn(2+) used in the first step of the synthesis; the NiSn nanoparticles remain encapsulated within the dendrimers, and when dry they have a degree of stability even after a short exposure to air.

10.
ACS Nano ; 4(2): 905-12, 2010 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-20112960

RESUMO

In this paper, we report the functionalization of the surface of multiwalled carbon nanotubes (MWNTs) with Au dendrimer encapsulated nanoparticles (DENs). The results show that, when pristine MWNTs having hydrophobic surfaces are exposed to DENs, the dendrimers aggregate on the MWNT surface. However, when the MWNTs are oxidized in acid prior to exposure to DENs, well-dispersed submonolayer coverages of Au nanoparticles are observed on the MWNT surface. This suggests that acid-induced debundling of the nanotubes is an essential prerequisite for attachment of nearly monodisperse DENs. Electron microscopy and NMR spectroscopy confirm that the structures of the DENs and dendrimers are retained after immobilization on the surface of acid-functionalized MWNTs.


Assuntos
Dendrímeros/química , Ouro/química , Nanopartículas/química , Nanotubos de Carbono/química , Espectroscopia de Ressonância Magnética , Solubilidade , Coloração e Rotulagem , Temperatura , Termogravimetria , Água/química
11.
J Am Chem Soc ; 131(41): 14634-5, 2009 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-19785420

RESUMO

High-resolution solution (1)H NMR spectroscopy has been used to characterize the size of Pd dendrimer-encapsulated nanoparticles (DENs). The Pd nanoparticles measured by this technique contain 55, 147, 200, or 250 atoms, and they are encapsulated within sixth-generation, hydroxyl-terminated poly(amidoamine) PAMAM dendrimers (G6-OH). Detailed analysis of the NMR data shows that signals arising from the innermost protons of G6-OH(Pd(n)) decrease significantly as the size of the encapsulated nanoparticles increase. A mathematical correlation between this decrease in the integral value and the theoretical number of Pd atoms in the nanoparticle is extracted. It enables the elucidation of the size of Pd DENs by (1)H NMR spectroscopy. NMR pulse-field gradient spin-echo experiments demonstrate that G6-OH with and without DENs have identical hydrodynamic radii, which excludes the presence of dendrimer/nanoparticle aggregates.

13.
Arch Ophthalmol ; 117(1): 94-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9930166

RESUMO

OBJECTIVE: To measure monocular distance visual acuity, near visual acuity, contrast sensitivity, and visual field extent in full-term, 10-year-old children tested according to the protocol used to test 10-year-old preterm children in the Cryotherapy for Retinopathy of Prematurity study. SUBJECTS AND METHODS: Subjects were 106 healthy, full-term children, 9.8 to 10.9 years of age, who had no ocular abnormalities other than ametropia. All were tested monocularly using Early Treatment and Diabetic Retinopathy Study distance and near visual acuity charts and Pelli-Robson contrast sensitivity charts, with refractive error corrected according to Cryotherapy for Retinopathy of Prematurity study criteria. Goldmann perimetry was tested without correction using the V-4-e and III-4-e stimuli along 8 meridia. A standard pediatric eye examination was performed on each subject. RESULTS: Mean (SD) distance visual acuity was 20/19.6 OD (0.082 log unit [lu]) and mean near visual acuity was 20/19.5 OD (0.100 lu). Mean (SD) contrast sensitivity was 1.69 OD (0.12 lu), with a mean (SD) of 36.4 (2.2) letters read. Visual field extent was larger for the V-4-e stimulus than for the III-4-e stimulus. CONCLUSIONS: The results provide the first monocular normative data from a large sample of 10-year-old children tested with Early Treatment and Diabetic Retinopathy Study distance and near visual acuity charts and the Pelli-Robson contrast sensitivity charts, and add to the literature on Goldmann perimetry in children.


Assuntos
Sensibilidades de Contraste/fisiologia , Acuidade Visual/fisiologia , Campos Visuais/fisiologia , Criança , Feminino , Humanos , Masculino , Valores de Referência , Testes de Campo Visual
14.
Gynecol Oncol ; 64(2): 285-7, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9038279

RESUMO

Radiation myelopathy is a severe consequence of radiation to the spinal cord which rarely occurs with standard doses of radiation. This entity commonly results in different degrees of sensory and motor deficits. Diagnosis of radiation myelopathy in women with gynecologic malignancies may increase with the concomitant use of chemotherapy and radiation therapy. This paper reports the effect of this combination therapy in a 60-year-old woman with fallopian tube carcinoma.


Assuntos
Neoplasias das Tubas Uterinas/tratamento farmacológico , Neoplasias das Tubas Uterinas/radioterapia , Lesões por Radiação/etiologia , Doenças da Medula Espinal/etiologia , Neoplasias das Tubas Uterinas/secundário , Feminino , Humanos , Pessoa de Meia-Idade
15.
Environ Manage ; 20(4): 497-521, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8661618

RESUMO

The ecosystems of South Florida are unique in the world. The defining features of the natural Everglades (large spatial scale, temporal patterns of water storage and sheetflow, and low nutrient levels) historically allowed a mosaic of habitats with characteristic animals. Massive hydrological alterations have halved the Everglades, and ecological sustainability requires fundamental changes in management.The US Man and the Biosphere Human-Dominated Systems Directorate is conducting a case study of South Florida using ecosystem management as a framework for exploring options for mutually dependent sustainability of society and the environment. A new methodology was developed to specify sustainability goals, characterize human factors affecting the ecosystem, and conduct scenario/consequence analyses to examine ecological and societal implications. South Florida has sufficient water for urban, agricultural, and ecological needs, but most water drains to the sea through the system of canals; thus, the issue is not competition for resources but storage and management of water. The goal is to reestablish the natural system for water quantity, timing, and distribution over a sufficient area to restore the essence of the Everglades.The societal sustainability in the Everglades Agricultural Area (EAA) is at risk because of soil degradation, vulnerability of sugar price supports, policies affecting Cuban sugar imports, and political/economic forces aligned against sugar production. One scenario suggested using the EAA for water storage while under private sugar production, thereby linking sustainability of the ecological system with societal sustainability. Further analyses are needed, but the US MAB project suggests achieving ecological sustainability consistent with societal sustainability may be feasible.

16.
Am J Perinatol ; 10(1): 17-20, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8442791

RESUMO

To evaluate the outcome of pregnancy in diabetic women who had an episode of ketoacidosis during gestation, 20 consecutive cases of ketoacidosis in type I diabetic pregnant women were studied. They were divided into two groups for comparison: Group 1, 13 patients (65%), had a live fetus and group 2, seven patients (35%), had a fetal death on admission. Both groups were similar in age, gravidity, parity, abortions, height, weight, serum sodium and potassium, arterial pH, carbon dioxide tension, bicarbonate, base excess, and anion gap. Significantly different between groups 1 and 2 were: gestational age (24 versus 31 weeks; p < 0.05), serum glucose (374 versus 830 mg/dl; p < 0.005), blood urea nitrogen (14 versus 23 mg/dl; p < 0.025), osmolality (295 versus 311 mmol/kg; p < 0.025), insulin requirements (127 versus 202 U; p < 0.05), and length of resolution (28 versus 38 hours; p < 0.05). Two patients had serum glucoses less than 200 mg/dl despite profound ketoacidosis. Precipitating factors included infections, poor compliance, and very importantly, unrecognized new onset of diabetes (6 patients). All stillborns were grossly normal and those autopsied had no discernible cause of death. There were no maternal deaths. A high fetal mortality (35%) was found but there were no fetal losses once therapy was initiated. The unrecognized new onset diabetics accounted for almost a third (30%) of the cases of ketoacidosis and for 57% of the fetal deaths. Attentiveness to the symptoms of uncontrolled diabetes and appropriate screening can be effective preventive measures.


Assuntos
Diabetes Gestacional/epidemiologia , Cetoacidose Diabética/epidemiologia , Morte Fetal/epidemiologia , Resultado da Gravidez/epidemiologia , Gravidez em Diabéticas/epidemiologia , Adulto , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Morte Fetal/etiologia , Idade Gestacional , Humanos , Gravidez
17.
Invest Ophthalmol Vis Sci ; 27(3): 429-33, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3949470

RESUMO

The role of heterozygous galactokinase deficiency in the development of presenile cataracts is presently undetermined. Erythrocyte galactokinase activity was measured from 95 normal Caucasian subjects and from 39 Caucasian patients who had developed idiopathic bilateral cataracts between ages 20 and 55. The diagnosis of heterozygous galactokinase deficiency was based on the following criteria: galactokinase activity more than 2.0 SD below the control population mean; when available, familial evidence for heterozygous galactokinase activity was used as additional evidence. Three of 39 patients (1/13) with cataracts were found to be carriers of the galactokinase deficiency allele (P less than 0.001). Two heterozygotes had high dietary galactose intake suggesting a possible relationship between a high galactose diet and cataract formation. Dietary information was unavailable for the third heterozygote. We conclude that there is a high prevalence of heterozygous galactokinase deficiency existing in patients less than 55 yr of age with cataracts, and recommend that adults at risk restrict their consumption of dairy products.


Assuntos
Catarata/genética , Galactoquinase/deficiência , Adolescente , Adulto , Idoso , Catarata/etiologia , Catarata/metabolismo , Dieta , Feminino , Galactose , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade
18.
Am J Hosp Pharm ; 42(12): 2679-83, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4083289

RESUMO

The loss of amiodarone from i.v. admixtures to flexible polyvinyl chloride (PVC) infusion bags and i.v. administration sets was studied. Admixtures containing amiodarone hydrochloride 600 micrograms/mL and either 5% dextrose injection or 0.9% sodium chloride injection were stored at room temperature in glass bottles (both with and without contact of the drug solution with the rubber bottle closure), in flexible PVC bags, or in rigid PVC bottles. After 120 hours, the contents of each flexible PVC bag were emptied and replaced by methanol, which was allowed to remain in the bag for an additional 120 hours and was then analyzed for amiodarone content. To determine availability of amiodarone after infusion through a 1.8-m PVC i.v. administration set, solutions stored in glass containers were run through the set at 0.5 mL/min for 90 minutes. Samples of drug solutions were collected at appropriate intervals and analyzed by a stability-indicating high-performance liquid chromatography (HPLC) assay. Admixtures containing 0.9% sodium chloride injection were not stable; visual incompatibility was evident after 24 hours of storage in glass bottles, and no further testing was performed. In admixtures containing 5% dextrose injection that were stored in 50-mL flexible PVC bags, 60% of the initial amiodarone concentration remained after 120 hours; approximately half of the lost drug was recovered with the methanol. In effluent collected from the PVC administration set, 82% of the initial amiodarone concentration remained. Amiodarone concentrations did not decrease appreciably, after storage in glass or rigid PVC bottles, indicating that drug loss was probably affected by the plasticizer, di-2-ethylhexyl phthalate.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Amiodarona/análise , Benzofuranos/análise , Adsorção , Amiodarona/administração & dosagem , Embalagem de Medicamentos , Estabilidade de Medicamentos , Infusões Parenterais , Cinética , Cloreto de Polivinila
19.
Biochim Biophys Acta ; 831(3): 306-12, 1985 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-4052432

RESUMO

A procedure for preparing a highly purified galactokinase (ATP:D-galactose 1-phosphotransferase, EC 2.7.1.6) from human erythrocytes and placenta is described, involving DEAE-Sephacel, ammonium sulfate fractionation, gel-filtration and a subsequent chromatography step on Blue Sepharose CL-6B. The final chromatography step yields a homogeneous preparation of high specific activity. The subunit molecular weight was determined to be 38 000 for both placental and erythrocyte galactokinases. Both active preparations of the native enzyme eluted from a gel filtration column gave a molecular weight of 37 000-38 000, thus suggesting the enzyme to be present in monomeric form. The isoelectric points for both crude and their respective purified enzymes was determined to be at pH 5.7. This method for purifying human galactokinase from placenta and erythrocytes represents a significant improvement over that previously reported and contradicts past evidence for the enzyme existing as a dimer.


Assuntos
Eritrócitos/enzimologia , Galactoquinase/isolamento & purificação , Placenta/enzimologia , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Feminino , Galactoquinase/sangue , Galactoquinase/metabolismo , Humanos , Peso Molecular , Gravidez
20.
Invest New Drugs ; 3(1): 51-6, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3988457

RESUMO

A sensitive and specific radioimmunoassay for mitoxantrone in serum has been developed. The procedure allows direct measurement of mitoxantrone in unextracted serum samples, by using antisera from rabbits immunized with mitoxantrone-BSA antigen. Tritiated mitoxantrone of high specific radioactivity (ca. 15 Ci/mmol) was used as a radio-tracer ligand. The assay allows the detection of as little as 50 pg/ml and the quantitation of 75 pg/ml in 0.5 ml serum samples. Standard curves were linear in the concentration range of 75-2500 pg/ml, at antiserum dilutions of 1:15,000. The assay shows good reproducibility: coefficients of variation of 3-6% were obtained by analyzing five samples/concentration at 75, 100, 250, 500, and 1000 pg/ml. There was no cross reactivity with the major metabolite in human serum, having concentrations of up to 10,000 pg/ml. Serum samples collected at various time intervals from rats dosed intravenously with mitoxantrone (0.5 mg/kg), were analyzed for unchanged mitoxantrone by RIA. The drug concentrations decreased from 32 ng/ml at 0.5 h to 0.45 ng/ml by 24 h after dosing. Mitoxantrone, a dihydroxyanthracenedione derivative (1), is an antitumor agent currently used in clinical trials with very encouraging results, especially in metastatic breast cancer, and low incidence of adverse reactions (2-4). The drug is being administered intravenously at doses up to 14 mg/m2. Preliminary pharmacokinetic studies (to be published separately) indicate rapid distribution, followed by slow clearance rates from the tissues. The sensitivity of the currently available (HPLC) methods (5, 6) is of about 5-20 ng/ml in serum.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Antraquinonas/sangue , Antineoplásicos/sangue , Radioimunoensaio/métodos , Animais , Antraquinonas/imunologia , Antineoplásicos/imunologia , Masculino , Mitoxantrona , Coelhos , Ratos , Ratos Endogâmicos
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