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1.
Chemistry ; 27(48): 12371-12379, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34137472

RESUMEN

We investigated the photoionization and fragmentation of isolated metal protoporphyrin IX cations (MPPIX+ with M=Fe, Co, Zn) by means of vacuum-ultraviolet (VUV) action spectroscopy in the energy range of 8.5-35 eV. Experiments were carried out in the gas phase by interfacing an electrospray ionization tandem mass spectrometer with a synchrotron beamline. The mass spectra and partial ion yields show that photoexcitation of the precursor ions predominantly leads to . CH2 COOH radical side-chain losses of the macrocycle with additional methyl radical (. CH3 ) side-chain losses. Ionization, in contrast, leads to the formation of the intact ionized precursor and various doubly charged fragments which are mostly due to side-chain cleavages. Although statistical fragmentation dominates, we found evidence for non-statistical processes such as new fragments involving for example single and double H2 O losses, indicating that different relaxation mechanisms are at play upon photoionization compared to photoexcitation. The measured ionization energies were 9.6±0.2 eV, 9.4±0.2 eV and 9.6±0.2 eV for FePPIX+ , CoPPIX+ and ZnPPIX+ , respectively.


Asunto(s)
Metaloporfirinas , Cationes , Espectrometría de Masas , Análisis Espectral , Rayos Ultravioleta
2.
J Therm Biol ; 98: 102908, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34016335

RESUMEN

Adverse weather conditions are important contributors to mortality in new-born lambs. Previous studies have shown variation between lambs in their ability to cope with circumstances of cold stress, and genetic selection could be a viable option for improving animal robustness. The Elsenburg Merino flock was divergently selected on number of lambs weaned (NLW). This resulted in divergent responses in reproduction and lamb survival. This study evaluated lamb vitality and mortality of positively selected H-Line relative to the negatively selected L-Line in response to cold stress. Traits included lamb rectal temperature (RT), surface temperature (ST), shiver score (SS), lamb vigor score (LVS), breaths per minute (BPM), mortality to three days of age (M3) and to weaning (TM). Cold stress was described by a chill index derived from daily rainfall, wind speed and ambient temperature, and represented as the mean of the one (CI), two (CI-2) or three (CI-3) days since parturition. Overall, H-Line lambs had a higher neonatal RT and were less likely to succumb than L-Line contemporaries. In a significant (P < 0.05) interaction, the predicted RT of L-Line showed a non-linear decline with increased levels of CI-2, while H-Line lambs better maintained their core temperature. M3 was also affected by a significant interaction between CI-3 and selection line, further suggesting that observed lower mortality rates in the H-Line depends on H-Line lambs' improved ability to cope with stressful environments. Long term selection for NLW in the H-Line led to improvements in both adaptations associated with lower lamb losses. The continued recording of viability traits to produce larger datasets amenable to genetic analysis is recommended, specifically for rectal temperature.


Asunto(s)
Respuesta al Choque por Frío/genética , Reproducción/genética , Ovinos/genética , Animales , Animales Recién Nacidos , Temperatura Corporal , Femenino , Masculino , Lluvia , Selección Genética , Temperatura , Viento
3.
J Therm Biol ; 99: 103024, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34420653

RESUMEN

This preliminary study investigated the provision of shade on heat stress indicators of South African Mutton Merino (SAMM) and Dormer lambs shortly after birth, during the autumn 2017 and 2018 lambing seasons. Newborn lambs were assessed to determine whether welfare, as assessed by respiratory response and rectal temperature as heat stress indicators, survival and early growth benefitted from the provision of shade. Groups consisting of 4-17 pregnant SAMM and Dormer ewes were randomly allocated to 5-10 paddocks with natural shade from trees and 5-9 paddocks that were directly in the sun with no shade available. The lambs were recorded within 24 h of birth at noon. Climate data were obtained from a nearby weather station. The lambs were also weighed at 12 (SD = 2) days of age at tail-docking. Tree shade had a moderating effect on temperature, resulting in lower maximum daytime and higher minimum night-time temperatures. There was an interaction between a temperature-humidity index (THI) and the treatments (access to shade or no access to shade) for respiration and rectal temperature (P < 0.01). Both traits were relatively unaffected by the THI at values below 77. Unshaded lambs exhibited a pronounced upwards trend following a THI-threshold of 77-78. Tailing weight tended to be higher while lamb survival of live-born lambs to tail-docking was lower in lambs born in shaded paddocks but these trends did not persist to weaning. Shade is needed to enhance animal welfare by alleviating the effect of high THI-values on hot days in an autumn lambing season.


Asunto(s)
Respuesta al Choque Térmico , Oveja Doméstica/fisiología , Árboles , Animales , Peso Corporal , Humedad , Estaciones del Año , Sudáfrica
4.
J Chem Phys ; 151(24): 244307, 2019 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-31893868

RESUMEN

The deconvolution of low-resolution time-of-flight data has numerous advantages, including the ability to extract additional information from the experimental data. We augment the well-known Lucy-Richardson deconvolution algorithm using various Bayesian prior distributions and show that a prior of second-differences of the signal outperforms the standard Lucy-Richardson algorithm, accelerating the rate of convergence by more than a factor of four, while preserving the peak amplitude ratios of a similar fraction of the total peaks. A novel stopping criterion and boosting mechanism are implemented to ensure that these methods converge to a similar final entropy and local minima are avoided. Improvement by a factor of two in mass resolution allows more accurate quantification of the spectra. The general method is demonstrated in this paper through the deconvolution of fragmentation peaks of the 2,5-dihydroxybenzoic acid matrix and the benzyltriphenylphosphonium thermometer ion, following femtosecond ultraviolet laser desorption.

5.
Anal Chem ; 90(7): 4422-4428, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29522677

RESUMEN

We report the soft laser extraction and production of highly charged peptide and protein ions for mass spectrometry directly from bulk liquid water at atmospheric pressure and room temperature, using picosecond infrared laser ablation. Stable ion signal from singly charged small molecules, as well as highly charged biomolecular ions, from aqueous solutions at low laser pulse fluence (∼0.3 J cm-2) is demonstrated. Sampling via single picosecond laser pulses is shown to extract less than 27 pL of volume from the sample, producing highly charged peptide and protein ions for mass spectrometry detection. The ablation and ion generation is demonstrated to be soft in nature, producing natively folded proteins ions under sample conditions described for native mass spectrometry. The method provides laser-based sampling flexibility, precision and control with highly charged ion production directly from water at low and near neutral pH. This approach does not require an additional ionization device or high voltage applied directly to the sample.


Asunto(s)
Rayos Láser , Espectrometría de Masas/métodos , Péptidos/química , Péptidos/aislamiento & purificación , Proteínas/química , Proteínas/aislamiento & purificación , Agua/química , Péptidos/análisis , Proteínas/análisis , Factores de Tiempo
6.
Biochem J ; 474(24): 4171-4192, 2017 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-29070524

RESUMEN

Previous work suggested that hemoglobin (Hb) tetramer formation slows autoxidation and hemin loss and that the naturally occurring mutant, Hb Providence (HbProv; ßK82D), is much more resistant to degradation by H2O2 We have examined systematically the effects of genetic cross-linking of Hb tetramers with and without the HbProv mutation on autoxidation, hemin loss, and reactions with H2O2, using native HbA and various wild-type recombinant Hbs as controls. Genetically cross-linked Hb Presbyterian (ßN108K) was also examined as an example of a low oxygen affinity tetramer. Our conclusions are: (a) at low concentrations, all the cross-linked tetramers show smaller rates of autoxidation and hemin loss than HbA, which can dissociate into much less stable dimers and (b) the HbProv ßK82D mutation confers more resistance to degradation by H2O2, by markedly inhibiting oxidation of the ß93 cysteine side chain, particularly in cross-linked tetramers and even in the presence of the destabilizing Hb Presbyterian mutation. These results show that cross-linking and the ßK82D mutation do enhance the resistance of Hb to oxidative degradation, a critical element in the design of a safe and effective oxygen therapeutic.


Asunto(s)
Hemoglobinas/química , Hemoglobinas/genética , Mutación Missense , Reactivos de Enlaces Cruzados/química , Dimerización , Hemoglobinas/metabolismo , Humanos , Peróxido de Hidrógeno/química , Oxidación-Reducción , Ingeniería de Proteínas
7.
Br J Dermatol ; 175(2): 391-3, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26877232

RESUMEN

Tumoral melanosis describes a pigmented lesion clinically similar to melanoma but on histology reveals dense aggregates of melanin-laden, benign macrophages without malignant cells. In the few reported cases so far, tumoral melanosis has arisen in the skin or lymph node of a patient with a regressed melanoma or an epithelioid tumour. As a marker of regressed primary melanoma, its discovery may prompt investigation and surveillance for undiagnosed local or metastatic disease. Here, we present a unique case of extensive tumoral melanosis arising during ipilimumab treatment of in-transit metastases from a previously excised melanoma.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Melanoma/tratamiento farmacológico , Melanosis/diagnóstico , Neoplasias Cutáneas/tratamiento farmacológico , Anciano , Diagnóstico Diferencial , Humanos , Ipilimumab , Masculino , Melanoma/diagnóstico , Melanoma/cirugía , Melanosis/tratamiento farmacológico , Melanosis/cirugía , Recurrencia Local de Neoplasia/diagnóstico , Reoperación , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/cirugía
9.
J Occup Rehabil ; 24(3): 410-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24026339

RESUMEN

PURPOSE: In the Netherlands, disability claimants are assessed after 2 years of sick leave, but their functioning may still improve. An accurate prognosis of functioning is difficult. Self predictions may be more accurate than those of professionals. The aim of this study, is to assess and compare the accuracy of predictions by disability claimants and insurance physicians (IPs) working at the Social Security Institute. It is further studied whether the accuracy differs between subgroups of claimants with mental or somatic health conditions. METHODS: We used data from the prospective cohort study cohort study. Following the assessment of the disability claim (n = 375) and after 1 year follow up (T1, n = 276) data on functioning were obtained from respondents by self-report questionnaire World Health Organization Disability Schedule 2.0. Both claimants and IPs were asked to predict improvement of functioning. Accuracy of their predictions were assessed by sensitivity, specificity, and area under the receiver operating curves (AUC). Mixed logistic regression was conducted to explore differences in accuracy between claimants with mental and somatic conditions. RESULTS: One-third (32 %) of disability claimants improved beyond the standard error of measurement. Disability claimants' and IPs were able to predict this improvement of functioning, but to a limited extent, with an AUC of 0.61 for IPs and 0.62 for disability claimants. We found no statistically significant differences in the accuracy of the predictions in claimants with mental or somatic health conditions. CONCLUSIONS: Improvements of functioning were not uncommon. However, both IPs and disability claimants were unable to predict improvement with high levels of accuracy in both mental and somatic health conditions.


Asunto(s)
Evaluación de la Discapacidad , Personas con Discapacidad/estadística & datos numéricos , Recuperación de la Función , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Revisión de Utilización de Seguros , Modelos Lineales , Masculino , Persona de Mediana Edad , Países Bajos , Curva ROC , Autoinforme , Ausencia por Enfermedad , Seguridad Social
10.
J Occup Rehabil ; 24(4): 680-91, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24519320

RESUMEN

OBJECTIVE: In most industrialized countries, disability benefit rates have increased substantially in the past decade. Few beneficiaries return into employment once disability benefit is awarded. The present study aims to investigate which factors predict functional improvement and future work status among persons claiming disability benefit after having been on long-term sickness leave. METHODS: Prospective cohort study with 1 year follow-up among disability claimants (n = 375; response rate: 24.3 %) conducted in the Netherlands (October 2008-April 2011). Logistic regression was used to analyze associations between predictors [demographics; outcomes of the 12-item General Health Questionnaire (GHQ-12); 10-item Kessler Psychological Distress scale; Alcohol Use Disorders Identification Test; Trimbos/iMTA questionnaire for Costs associated with Psychiatric Illness; Utrecht Coping List; Social Support Questionnaire for Transactions and Satisfaction; certified International Classification of Diseases 10th edition (ICD-10) diagnosis; loss of earning capacity (LEC)] and outcomes [functional improvement on the World Health Organization Disability Schedule 2.0 (WHODAS 2.0) exceeding the standard error of measurement; work status at follow-up]. RESULTS: Functional improvement on total WHODAS was reported by 84 (31.9 % of 263 claimants included in analysis). Of those not having work at baseline (n = 338), 34 (9.1 %) respondents had paid work 1 year later. Predictors of functional improvement: GHQ-12 sum score >20 [odds ratios (OR) 2.9; 95 % confidence intervals (CI) 1.54-5.34]; of future work status: work status at baseline (OR 16.8; 95 % CI 6.55-43.14), LEC < 80 % (OR 4.6; 95 % CI 1.87-11.42), contact with a medical specialist (OR 0.4; 95 % CI 0.19-0.87). CONCLUSIONS: Only a limited number of factors were found to significantly predict functional improvement and return to paid work after the disability benefit claim, having paid work at baseline being by far the most important factor.


Asunto(s)
Evaluación de la Discapacidad , Beneficios del Seguro , Seguro por Discapacidad , Reinserción al Trabajo/tendencias , Adulto , Empleo , Femenino , Predicción , Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Estudios Prospectivos , Ausencia por Enfermedad , Encuestas y Cuestionarios
11.
Int J Law Psychiatry ; 94: 101989, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38663172

RESUMEN

BACKGROUND: Verbal and physical violence in psychiatric hospitals can have harmful consequences for staff members, such as physical injury, traumatisation, and sick leave, and they often accompany involuntary admission. Harm to others may co-occur with self-harm, i.e., dual harm. However, little is known about the association between dual-harm and violent behaviour towards staff members and its clinical outcomes, such as seclusion and rapid tranquilisation after involuntary admission to a psychiatric inpatient unit. METHOD: A convenience sample of patients admitted involuntarily (N = 384; mean age = 48.03, SD = 19.92) between January 2016 and December 2019 in Western Brabant, the Netherlands, was used to design a retrospective file audit. Distinct harm groups, marked by the presence/absence of self- and/or other-harm, were investigated using multivariate linear regression modelling on the seriousness of violent acts and the total length of admission. Logistic regression analyses were used to study the association between harm groups and the administration of rapid tranquilisation, seclusion, and extended involuntary admissions. RESULTS: Several harm groups were identified, including self-harm only, other-harm only, and dual-harm groups. Psychiatric patients admitted to the hospital because of (the risk of) violence towards others had a higher risk of violent incidents during admission and some restrictive measures. In a subgroup of patients with psychotic disorders, patients with dual harm committed the most serious violent incidents compared to those in the other harm groups. CONCLUSION: Distinct harm groups were identified in a sample of involuntarily admitted patients. In a general adult psychiatric setting, patients at risk for violent behaviour, especially dual-harm patients, should be identified and monitored as part of the risk assessment. Future research is needed to explore more clinical correlates in the proposed distinction between harmful groups and to assess long-term prognosis.


Asunto(s)
Hospitales Psiquiátricos , Conducta Autodestructiva , Humanos , Países Bajos , Masculino , Femenino , Conducta Autodestructiva/psicología , Persona de Mediana Edad , Adulto , Estudios Retrospectivos , Violencia/psicología , Trastornos Mentales/psicología , Trastornos Mentales/epidemiología , Internamiento Obligatorio del Enfermo Mental , Anciano
12.
Biochem J ; 433(1): 163-74, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-20950274

RESUMEN

NOSs (NO synthases, EC 1.14.13.39) are haem-thiolate enzymes that catalyse a two-step oxidation of L-arginine to generate NO. The structural and electronic features that regulate their NO synthesis activity are incompletely understood. To investigate how haem electronics govern the catalytic properties of NOS, we utilized a bacterial haem transporter protein to overexpress a mesohaem-containing nNOS (neuronal NOS) and characterized the enzyme using a variety of techniques. Mesohaem-nNOS catalysed NO synthesis and retained a coupled NADPH consumption much like the wild-type enzyme. However, mesohaem-nNOS had a decreased rate of Fe(III) haem reduction and had increased rates for haem-dioxy transformation, Fe(III) haem-NO dissociation and Fe(II) haem-NO reaction with O2. These changes are largely related to the 48 mV decrease in haem midpoint potential that we measured for the bound mesohaem cofactor. Mesohaem nNOS displayed a significantly lower Vmax and KmO2 value for its NO synthesis activity compared with wild-type nNOS. Computer simulation showed that these altered catalytic behaviours of mesohaem-nNOS are consistent with the changes in the kinetic parameters. Taken together, the results of the present study reveal that several key kinetic parameters are sensitive to changes in haem electronics in nNOS, and show how these changes combine to alter its catalytic behaviour.


Asunto(s)
Hemo/química , Mesoporfirinas/química , Óxido Nítrico Sintasa de Tipo I/química , Proteínas Bacterianas , Transporte Biológico , Catálisis , Electrones , Hemo/metabolismo , Cinética , Óxido Nítrico Sintasa de Tipo I/metabolismo , Oxidación-Reducción
13.
J Occup Rehabil ; 21(2): 259-74, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21057974

RESUMEN

INTRODUCTION In the past few decades, mental health problems have increasingly contributed to sickness absence and long-term disability. However, little is known about prognostic factors of return to work (RTW) and disability of persons already on sick leave due to mental health problems. Understanding these factors may help to develop effective prevention and intervention strategies to shorten the duration of disability and facilitate RTW. METHOD We reviewed systematically current scientific evidence about prognostic factors for mental health related long term disability, RTW and symptom recovery. Searching PubMed, PsycINFO, Embase, Cinahl and Business Source Premier, we selected articles with a publication date from January 1990 to March 2009, describing longitudinal cohort studies with a follow-up period of at least 1 year. Participants were persons on sick leave or receiving disability benefit at baseline. We assessed the methodological quality of included studies using an established criteria list. Consistent findings in at least two high quality studies were defined as strong evidence and positive findings in one high quality study were defined as limited evidence. RESULTS Out of 796 studies, we included seven articles, all of high methodological quality describing a range of prognostic factors, according to the ICF-model categorized as health-related, personal and external factors. We found strong evidence that older age (>50 years) is associated with continuing disability and longer time to RTW. There is limited evidence for the association of other personal factors (gender, education, history of previous sickness absence, negative recovery expectation, socio-economic status), health related (stress-related and shoulder/back pain, depression/anxiety disorder) and external i.e., job-related factors (unemployment, quality and continuity of occupational care, supervisor behavior) with disability and RTW. We found limited evidence for the association of personal/external factors (education, sole breadwinner, partial/full RTW, changing work tasks) with symptom recovery. CONCLUSION This systematic review identifies a number of prognostic factors, some more or less consistent with findings in related literature (mental health factors, age, history of previous sickness absence, negative recovery expectation, socio-economic status, unemployment, quality and continuity of occupational care), while other prognostic factors (gender, level of education, sole breadwinner, supervisor support) conflict with existing evidence. There is still great need for research on modifiable prognostic factors of continuing disability and RTW among benefit claimants with mental health problems. Recommendations are made as to directions and methodological quality of further research, i.e., prognostic cohort studies.


Asunto(s)
Trastornos Mentales/diagnóstico , Ausencia por Enfermedad , Factores de Edad , Evaluación de la Discapacidad , Humanos , Pronóstico , Factores de Tiempo
14.
Materials (Basel) ; 14(18)2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34576614

RESUMEN

Na-ß″-alumina is the commercially most successful solid electrolyte due to its application in ZEBRA and NAS® batteries. In this work, Li-stabilized Na-ß″-alumina electrolytes were doped with 3d transition metal oxides, namely TiO2, Mn3O4, and NiO, in order to improve their ionic conductivity and fracture strength. Due to XRD and EDX measurements, it was concluded that Mn- and Ni-ions are incorporated into the crystal lattice of Na-ß″-alumina. In contrast, TiO2 doping results in the formation of secondary phases that enable liquid-assisted sintering at temperatures as low as 1500 °C. All dopants increased the characteristic fracture strength of the electrolytes; 1.5 wt% of NiO doping proved to be most efficient and led to a maximal characteristic fracture strength of 296 MPa. Regarding the ionic conductivity, TiO2 doping showed the uppermost value of up to 0.30 S cm-1 at 300 °C. In contrast to the other dopants, TiO2 doping lowered the sintering temperature needed to obtain a dense, stable, and highly conductive Na-ß″-alumina electrolyte suitable for applications in Na based batteries.

15.
J Phys Chem Lett ; 11(20): 8616-8622, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32960067

RESUMEN

Femtosecond laser desorption postionization mass spectrometry using 7.9 eV single-photon ionization (7.9 eV fs-LDPI-MS) detected three of four drug compounds previously found to have very low ionization efficiencies by secondary ion mass spectrometry. Electronic structure calculations of the ionization energies and other properties of these four drug compounds predicted that all display ionization energies below the 7.9 eV photon energy, as required for single-photon ionization. The 7.9 eV fs-LDPI-MS of carbamazepine, imipramine, and verapamil all showed significant precursor (M+) ion signal, but no representative signal was observed for ciprofloxacin. Furthermore, 7.9 eV fs-LDPI-MS displayed higher M+ signals and mostly similar fragment ions compared with 70 eV electron impact mass spectrometry. Ionization and fragmentation patterns are discussed in terms of calculated wave functions for the highest occupied molecular orbitals. The implications for improving lateral resolution and sensitivity of MS imaging of drug compounds are also considered.


Asunto(s)
Carbamazepina/química , Ciprofloxacina/química , Imipramina/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Verapamilo/química , Iones/química , Cinética , Rayos Láser , Modelos Moleculares , Conformación Molecular
16.
Annu Rev Anal Chem (Palo Alto Calif) ; 12(1): 201-224, 2019 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-30848927

RESUMEN

There is an increasing appreciation that every cell, even of the same type, is different. This complexity, when additionally combined with the variety of different cell types in tissue, is driving the need for spatially resolved omics at the single-cell scale. Rapid advances are being made in genomics and transcriptomics, but progress in metabolomics lags. This is partly because amplification and tagging strategies are not suited to dynamically created metabolite molecules. Mass spectrometry imaging has excellent potential for metabolic imaging. This review summarizes the recent advances in two of these techniques: matrix-assisted laser desorption ionization (MALDI) and secondary ion mass spectrometry (SIMS) and their convergence in subcellular spatial resolution and molecular information. The barriers that have held back progress such as lack of sensitivity and the breakthroughs that have been made including laser-postionization are highlighted as well as the future challenges and opportunities for metabolic imaging at the single-cell scale.


Asunto(s)
Metabolómica/métodos , Análisis de la Célula Individual/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masa de Ion Secundario/métodos , Animales , Humanos , Metaboloma , Metabolómica/instrumentación , Análisis de la Célula Individual/instrumentación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/instrumentación , Espectrometría de Masa de Ion Secundario/instrumentación
17.
J Health Econ ; 27(4): 959-972, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18207264

RESUMEN

OBJECTIVES: This study estimates the value that clients place on methadone maintenance and how this value varies with the effectiveness of treatment and availability of case management. We provide the first estimate of the price elasticity of the demand for drug treatment. METHODS: We interviewed 241 heroin users who had been referred to, but had not yet entered, methadone maintenance treatment in Baltimore, Maryland. We asked each subject to state a preference among three hypothetical treatment programs that varied across three domains: weekly fee paid by the client out-of-pocket ($5-$100), presence/absence of case management, and time spent heroin-free (3-24 months). Each subject was asked to complete 18 orthogonal comparisons. Subsequently each subject was asked if they likely would enroll in their preferred choice among the set of three. We computed the expected willingness to pay (WTP) as the probability of enrollment times the fee considered in each choice considered from a multivariate logistic model that controlled for product attributes. We also estimated the price elasticity of demand. RESULTS: The median expected fee subjects were willing to pay for a program that offered 3 months of heroin-free time was $7.30 per week, rising to $17.11 per week for programs that offered 24 months of heroin-free time. The availability of case management increased median WTP by $5.64 per week. The price elasticity was -0.39 (S.E. 0.042). CONCLUSIONS: Clients will pay more for higher rates of treatment success and for the presence of case management. Clients are willing to pay for drug treatment but the median willingness to pay falls short of the estimated program costs of $82 per week. Thus a combined approach of user fees and subsidization may be the optimal financing strategy for the drug treatment system.


Asunto(s)
Financiación Personal , Aceptación de la Atención de Salud , Rehabilitación/economía , Trastornos Relacionados con Sustancias/rehabilitación , Adulto , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad
18.
Ann Pharmacother ; 42(1): 32-8, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18056833

RESUMEN

BACKGROUND: The behavioral and psychological symptoms related to dementia (BPSD) are difficult to manage and are associated with adverse patient outcomes. OBJECTIVE: To systematically analyze the data on memantine in the treatment of BPSD. METHODS: We searched MEDLINE, EMBASE, Pharm-line, the Cochrane Centre Collaboration, www.clinicaltrials.gov, www.controlled-trials.com, and PsycINFO (1966-July 2007). We contacted manufacturers and scrutinized the reference sections of articles identified in our search for further references, including conference proceedings. Two researchers (IM and CF) independently reviewed all studies identified by the search strategy. We included 6 randomized, parallel-group, double-blind studies that rated BPSD with the Neuropsychiatric Inventory (NPI) in our meta-analysis. Patients had probable Alzheimer's disease and received treatment with memantine for at least one month. Overall efficacy of memantine on the NPI was established with a t-test for the average difference between means across studies, using a random effects model. RESULTS: Five of the 6 studies identified had NPI outcome data. In these 5 studies, 868 patients were treated with memantine and 882 patients were treated with placebo. Patients on memantine improved by 1.99 on the NPI scale (95% Cl -0.08 to -3.91; p = 0.041) compared with the placebo group. CONCLUSIONS: Initial data appear to indicate that memantine decreases NPI scores and may have a role in managing BPSD. However, there are a number of limitations with the current data; the effect size was relatively small, and whether memantine produces significant clinical benefit is not clear.


Asunto(s)
Demencia/tratamiento farmacológico , Antagonistas de Aminoácidos Excitadores/uso terapéutico , Memantina/uso terapéutico , Anciano , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/psicología , Síntomas Conductuales/tratamiento farmacológico , Demencia/complicaciones , Demencia/psicología , Femenino , Humanos , Masculino , Modelos Estadísticos , Escalas de Valoración Psiquiátrica , Ensayos Clínicos Controlados Aleatorios como Asunto
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