Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
1.
J Adv Model Earth Syst ; 14(3): e2021MS002784, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35860446

RESUMEN

Tropical peatlands are among the most carbon-dense ecosystems on Earth, and their water storage dynamics strongly control these carbon stocks. The hydrological functioning of tropical peatlands differs from that of northern peatlands, which has not yet been accounted for in global land surface models (LSMs). Here, we integrated tropical peat-specific hydrology modules into a global LSM for the first time, by utilizing the peatland-specific model structure adaptation (PEATCLSM) of the NASA Catchment Land Surface Model (CLSM). We developed literature-based parameter sets for natural (PEATCLSMTrop,Nat) and drained (PEATCLSMTrop,Drain) tropical peatlands. Simulations with PEATCLSMTrop,Nat were compared against those with the default CLSM version and the northern version of PEATCLSM (PEATCLSMNorth,Nat) with tropical vegetation input. All simulations were forced with global meteorological reanalysis input data for the major tropical peatland regions in Central and South America, the Congo Basin, and Southeast Asia. The evaluation against a unique and extensive data set of in situ water level and eddy covariance-derived evapotranspiration showed an overall improvement in bias and correlation compared to the default CLSM version. Over Southeast Asia, an additional simulation with PEATCLSMTrop,Drain was run to address the large fraction of drained tropical peatlands in this region. PEATCLSMTrop,Drain outperformed CLSM, PEATCLSMNorth,Nat, and PEATCLSMTrop,Nat over drained sites. Despite the overall improvements of PEATCLSMTrop,Nat over CLSM, there are strong differences in performance between the three study regions. We attribute these performance differences to regional differences in accuracy of meteorological forcing data, and differences in peatland hydrologic response that are not yet captured by our model.

2.
Hum Reprod Open ; 2020(3): hoaa041, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32995565

RESUMEN

STUDY QUESTION: What are the patient-specific determinants associated with patient-centered endometriosis care as measured by the ENDOCARE questionnaire (ECQ)? SUMMARY ANSWER: 'Overall grade for endometriosis care', 'educational level', 'membership of a patient organization' and 'having seen other specialists for endometriosis complaints' are correlated with overall patient-centeredness scores (PCS). WHAT IS KNOWN ALREADY: Patient-centeredness of endometriosis care can be evaluated using the validated ECQ. The ECQ leads to an overall PCS and separate PCS for 10 dimensions of endometriosis care. Previously, educational level and quality of life scores were found to be associated with ECQ results. STUDY DESIGN SIZE DURATION: First, a systematic literature review was performed (PROSPERO registration number: CRD42020169872). MEDLINE, Cochrane CENTRAL and EMBASE databases were searched from inception to May 2020 for studies in any language reporting on the results of the ECQ in patients with endometriosis. Two studies were identified. From the two studies, all original data were merged. In total, data from 546 patients were available for analysis. Second, univariate and multivariate regression analyses were performed to identify determinants for patient-centeredness of endometriosis care. PARTICIPANTS/MATERIALS SETTING METHODS: The two included studies evaluated patient-centeredness in four endometriosis care centers in Belgium and the Netherlands. All participants had surgically proven endometriosis. Possible patient-specific determinants were selected from the demographic and medical questions from the first part of the ECQ. These determinants were evaluated using linear regression analysis and all possible determinants with a P > 0.2 in the univariate analysis were selected for stepwise multivariate analysis. Separate analyses were performed for overall PCS and each of the 10 dimensions. MAIN RESULTS AND THE ROLE OF CHANCE: The two included studies provided data from 546 patients. After adjustment for care center, multivariate analysis showed that a higher 'grade for endometriosis care' (B = 0.66), a 'lower educational level' (B = 0.50), 'being member of a patient organization' (B = 0.49) and 'having seen other specialists for endometriosis complaints' (B = 0.34) were independently associated with higher overall PCS (R 2 = 0.41). 'Grade for endometriosis care' was a determinant for all dimensions of endometriosis care. 'Having seen other specialists for endometriosis complaints' was positively associated with the care dimensions 'respect for patients' values, preferences and expressed needs', 'continuity and transition' and 'technical skills'. Members of a patient organization showed higher scores on the care dimensions 'emotional support and alleviation of fear and anxiety', 'continuity and transition' and 'endometriosis clinic staff'. Furthermore, we found that having a higher level of education is associated with lower scores in the care dimensions 'physical comfort', 'emotional support and alleviation of fear and anxiety' and 'involvement of significant other'. LIMITATIONS REASONS FOR CAUTION: These results delineate the patient-specific determinants of patient-centered care as measured using the Dutch ECQ. Whether results are generalizable to other countries should be investigated in an international study. This requires the ECQ to be validated in other languages first. WIDER IMPLICATIONS OF THE FINDINGS: The aforementioned determinants of patient-centered care are of value for studies benchmarking clinics for their patient-centeredness. In addition, they help clinicians to determine how to tailor their care to individual patients. At every visit, patients could be asked to grade the endometriosis care (on a scale of 0-10) to easily investigate patient-centeredness. When there is more time, women with endometriosis should be asked to complete the entire ECQ to investigate patient-centeredness in depth. STUDY FUNDING/COMPETING INTERESTS: The department of reproductive medicine (involving C.B.L. and V.M.) of the Amsterdam UMC, Vrije Universiteit Amsterdam has received several research and educational grants from Guerbet, Merck and Ferring. The authors have no conflict of interest related to this manuscript.

3.
Hum Reprod Open ; 2020(3): hoaa029, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32695888

RESUMEN

STUDY QUESTION: What is the performance of the patient-centredness of endometriosis care in a secondary and a tertiary care setting and how can it be improved? SUMMARY ANSWER: Overall, patient-centredness was comparable in the two endometriosis care centres, but differed regarding 'physical comfort' and 'continuity and transition'; both centres can learn how to improve several of their targets from the other's strengths. WHAT IS KNOWN ALREADY: The ENDOCARE questionnaire (ECQ) is a validated questionnaire for assessing the important quality dimension 'patient-centredness'. Patient-centredness is associated with quality of life, although this should be explored further by larger-scale studies. STUDY DESIGN SIZE DURATION: A cross-sectional survey, relying on the ECQ, was performed (during 2015 and 2016) among 407 women with surgically diagnosed endometriosis. PARTICIPANTS/MATERIALS SETTING METHODS: This study was conducted in a secondary and a tertiary care centre in the Netherlands. A total of 209 Dutch-speaking women who had endometriosis surgery (2013-2014), completed the ECQ after a postal invitation and, if needed, postal reminders. The assessed outcomes were: overall patient-centredness, the patient-centredness for each of its 10 dimensions, and the patient-centred strengths and targets for improvement. Case-mix adjusted patient-centredness scores (PCS) were compared and strengths and targets for improvement were identified with a matrix modelling importance against experience. The need to improve the targets was quantified with quality impact indices. MAIN RESULTS AND THE ROLE OF CHANCE: No difference was demonstrated between the overall PCS of the secondary and tertiary centres (respectively: 4.8 and 4.5; P = 0.15). No difference was found in PCS per dimension between the two clinics except for the secondary care centre performing better regarding 'physical comfort' (respectively: 4.5 and 3.0; P = 0.01) and 'continuity and transition' (respectively: 6.0 and 4.2; P = 0.01). The two centres had nine targets for improvement in common. The secondary and tertiary centres, respectively, had five and seven additional centre-specific targets for improvement. Cross-centre learning is encouraged as 9 out the 12 additional centre-specific targets were strengths in the other centre. The main improvement targets were being able to contact the centre in case of emergency (both centres), the involvement of a significant other (secondary centre), diagnostic delay (secondary centre), personal follow-up (tertiary centre) and disclosing the level of competence of healthcare providers (tertiary centre). LIMITATIONS REASON FOR CAUTION: Responders did not differ from non-responders in their stage of endometriosis, educational level, rating of endometriosis care and degree to which their complaints are suppressed. Endometriosis is a chronic condition and patient-centredness might be experienced differently at other points of the endometriosis care trajectory. WIDER IMPLICATION OF THE FINDINGS: The ECQ is a useful tool to assess patient-centredness in both secondary and tertiary care centres. Further research should focus on how to improve endometriosis care. STUDY FUNDING/COMPETING INTERESTS: No external funding was used. V.M. and C.B.L. report grants from Guerbet, grants from Merck and grants from Ferring outside the submitted work. All authors declare that they have no competing interests concerning this publication.

4.
Hum Reprod ; 35(8): 1839-1854, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32649754

RESUMEN

STUDY QUESTION: Can we develop a web-based sex education programme (programme running in a web browser) that addresses the needs of subfertile couples who are advised expectant management for at least 6 months? SUMMARY ANSWER: The 'Pleasure & Pregnancy' programme addresses couples' needs, is likely to improve couples' sexual functioning, and is subsequently hypothesised to improve the chance of natural pregnancy. WHAT IS KNOWN ALREADY: According to professional guidelines (e.g. the Netherlands and UK) couples with unexplained subfertility and a good chance of natural pregnancy, should be advised at least 6 months of expectant management. Adherence to expectant management is challenging as couples and gynaecologist prefer a more active approach. Targeting sexuality may be useful as subfertility is a risk factor for decreased sexual functioning. STUDY DESIGN, SIZE, DURATION: A novel programme was developed according to the three steps of the Medical Research Councils' (MRC) framework. First, relevant literature was explored. Second, an interdisciplinary expert panel developed a theory (based on a systematic literature review and patient interviews) on how the chance of natural conception can be improved. Third, the expected process and outcomes were modelled. PARTICIPANTS/MATERIALS, SETTING, METHODS: Two licenced clinical sexologists, two gynaecologists, a clinical embryologist and two midwife-researchers, all from Belgium and the Netherlands, proposed components for the sex education programme. PubMed was searched systematically for randomised controlled trials (RCTs) evaluating the proposed components in different patient populations. The needs of 12 heterosexual Dutch or Belgian couples who were advised expectant management were explored with in-depth interviews. The content and delivery characteristics of the novel programme were described in detail with the aid of 'Intervention Taxonomy'. To model the outcomes, a protocol for an RCT was designed, registered and submitted for publication. MAIN RESULTS AND THE ROLE OF CHANCE: To help maintain or improve sexual functioning, mainly pleasure, and hence increase pregnancy rates, the web-based Pleasure & Pregnancy programme contains a combination of psychosexual education and couple communication, mindfulness and sensate focus exercises. Information on the biology of conception and interaction with fertility clinic staff and peers were added based on couples' needs to increase potential acceptability. LIMITATIONS AND REASON FOR CAUTION: This paper outlines the development phase of a sex education programme according to the MRC-framework. Whether the Pleasure & Pregnancy programme actually is acceptable, improves sexual functioning, increases pregnancy rates and is cost-effective remains to be determined. WIDER IMPLICATIONS OF THE FINDINGS: No previous interactive web-based sex education programme has aimed to increase the natural pregnancy rate of subfertile couples by targeting their sexual pleasure. The Pleasure & Pregnancy programme addresses couples' needs and its effect on sexual functioning and pregnancy rate is plausible but remains to be demonstrated by an RCT which is currently ongoing. STUDY FUNDING/COMPETING INTEREST(S): Funding was provided by The Netherlands Organisation for Health Research and Development (ZonMw), Flanders Research Foundation and the University of Amsterdam. C.B.L. is editor-in-chief of Human Reproductionbut was blinded to all parts of the peer review process. The remaining authors have no conflict of interest to report. TRIAL REGISTRATION NUMBER: Not applicable.


Asunto(s)
Infertilidad , Educación Sexual , Bélgica , Femenino , Humanos , Infertilidad/terapia , Internet , Países Bajos , Placer , Embarazo , Índice de Embarazo , Revisiones Sistemáticas como Asunto
5.
Artículo en Inglés | MEDLINE | ID: mdl-29580773

RESUMEN

The patient-centeredness of care is important for health care quality, especially because it was recently associated with health-related quality of life, which is increasingly being recognized as the ultimate outcome parameter of health care. Therefore, insight into the definition, measurement, and current status of the patient-centeredness of clinics is important for all health care professionals caring for patients with endometriosis. The definition of patient-centered endometriosis care is based on research into the most common preferences, needs, and values of patients with endometriosis and can be summarized in ten dimensions. One valid and reliable questionnaire exists, the ENDOCARE questionnaire, which allows measuring the patient-centeredness status of an endometriosis clinic. This questionnaire has been used to benchmark centers in different countries and has allowed the identification of ten targets for improving the patient-centeredness of endometriosis care. The next step would be to use the ENDOCARE questionnaire before and after an improvement project.


Asunto(s)
Endometriosis/psicología , Atención Dirigida al Paciente/normas , Garantía de la Calidad de Atención de Salud/métodos , Encuestas y Cuestionarios/normas , Endometriosis/terapia , Femenino , Humanos , Satisfacción del Paciente , Calidad de Vida
6.
Talanta ; 164: 490-502, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28107963

RESUMEN

Erectile dysfunction (ED) is a sexual disorder characterized by the inability to achieve or maintain a sufficiently rigid erection. Despite the availability of non-invasive oral treatment options, many patients turn to herbal alternatives. Furthermore, herbal supplements are increasingly gaining popularity in industrialized countries and, as a consequence, quality control is a highly important issue. Unfortunately, this is not a simple task since plants are often crushed and mixed with other plants, which complicates their identification by usage of classical approaches such as microscopy. The aim of this study was to explore the potential use of chromatographic fingerprinting to identify plants present in herbal preparations intended for the treatment of ED. To achieve this goal, a HPLC-PDA and a HPLC-MS method were developed, using a full factorial experimental design in order to acquire characteristic fingerprints of three plants which are potentially beneficial for treating ED: Epimedium spp., Pausinystalia yohimbe and Tribulus terrestris. The full factorial design demonstrated that for all three plant references a C8 column (250mm×4.6mm; 5µm particle size) is best suited; methanol and an ammonium formate buffer (pH 3) were found to be the best constituents for the mobile phase. The suitability of this strategy was demonstrated by analysing several self-made triturations in three different botanical matrices, which mimic the influential effects that could be expected when analysing herbal supplements. To conclude, this study demonstrates that chromatographic fingerprinting could provide a useful means to identify plants in a complex herbal mixture.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Fraude/prevención & control , Espectrometría de Masas
7.
Drug Test Anal ; 9(2): 230-242, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27006262

RESUMEN

Herbal medicines and food supplements intended as slimming aids are increasingly gaining popularity worldwide, especially for treating obesity. In this study, an ultra-performance liquid chromatography coupled to photodiode array detection (UPLC-PDA) and an ultra-performance liquid chromatography mass spectrometry (UPLC-MS) method were developed to analyze 92 slimming aids (confiscated by customs), aimed at acquiring highly informative fingerprints. Three types of fingerprints were acquired (PDA, Total Ion Chromatograms (TIC), and MS fingerprints) which were used in the chemometric data analysis. Both unsupervised (i.e., Hierarchical Cluster Analysis (HCA)) and supervised techniques (i.e., Classification and Regression Tree (CART) and Partial Least Squares - Discriminant Analysis (PLS-DA)) were applied. The aim was to perform an in-depth study of the samples, thereby exploring potential patterns present in the data. HCA was able to generate a clustering which was mainly defined by chemical compounds detected in the samples, i.e., sibutramine, phenolphthalein and amfepramone. PLS-DA generated the best diagnostic models for both PDA and TIC fingerprints, characterized by correct classification rates of external validation of 85% and 80%, respectively. For the MS fingerprints, the best model was obtained by CART (65% correct classification rate of external validation). Despite a lower correct classification rate, exploration of the concerned misclassifications revealed that the MS fingerprints proved to be superior since even very low concentrations of sibutramine could be detected. This study shows that reliable chemometric models can be obtained, based on the presence of prohibited chemical substances, which allow high-throughput data analysis of such samples. Moreover, they generate a prime notion of potential threat to a patient's health posed by these kinds of slimming aids. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Fármacos Antiobesidad/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Análisis por Conglomerados , Análisis Discriminante , Análisis de los Mínimos Cuadrados , Análisis de Componente Principal
8.
J Ethnopharmacol ; 193: 510-516, 2016 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-27693770

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The Nkundo people (Nkundo area of Bolongo, Mai-Ndombe district, Bandundu Province, DR Congo) use various plant parts of the tree Greenwayodendron suaveolens (Engl. & Diels) Verdc. (syn. Polyalthia suaveolens Engl. & Diels) (Annonaceae) against malaria, but its antiprotozoal constituents are not known. MATERIALS AND METHODS: The crude 80% ethanol extract from the fruits, leaves, root bark and stem bark and 16 fractions were assessed in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, T. cruzi, Leishmania infantum and the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum (Pf-K1). Their cytotoxic effects were evaluated against MRC-5 cells. Active constituents were isolated by chromatographic means, identified using spectroscopic methods, and evaluated in the same assays. RESULTS: The root bark extract showed the highest activity against P. falciparum K1 (IC50 0.26µg/mL) along with the stem bark alkaloid fraction (IC50 0.27µg/mL). The root bark alkaloid fraction had a pronounced activity against all selected protozoa with IC50 values <1µg/mL. The 90% methanol fractions of the different plant parts showed a pronounced activity against P. falciparum K1, with IC50 values ranging between 0.36µg/mL and 0.69µg/mL. Four constituents were isolated: the triterpenes polycarpol, and dihydropolycarpol, the latter one being reported for the first time from nature, and the alkaloids polyalthenol and N-acetyl-polyveoline. They were active to a various degree against one or more protozoa, mostly accompanied by cytotoxicity. The highest selectivity was observed for N-acetyl-polyveoline against P. falciparum K1 (IC50 2.8µM, selectivity index 10.9). CONCLUSIONS: These results may explain at least in part the traditional use of this plant species against parasitic diseases such as malaria in DR Congo.


Asunto(s)
Antimaláricos/farmacología , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Plasmodium falciparum/efectos de los fármacos , Polyalthia/química , Tripanocidas/farmacología , Antimaláricos/aislamiento & purificación , Antimaláricos/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Frutas/química , Humanos , Concentración 50 Inhibidora , Leishmania infantum/efectos de los fármacos , Leishmania infantum/crecimiento & desarrollo , Pruebas de Sensibilidad Parasitaria , Fitoquímicos/aislamiento & purificación , Fitoquímicos/toxicidad , Fitoterapia , Corteza de la Planta/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Hojas de la Planta/química , Raíces de Plantas/química , Plantas Medicinales , Plasmodium falciparum/crecimiento & desarrollo , Tripanocidas/aislamiento & purificación , Tripanocidas/toxicidad , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/crecimiento & desarrollo
9.
J Ethnopharmacol ; 192: 302-308, 2016 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-27394387

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Boldoa purpurascens Cav. (Nyctaginaceae) is a plant species used in traditional medicine in Cuba as a diuretic. AIM OF THE STUDY: The aim of the present investigation was to evaluate the safety profile of a hydroalcoholic extract from leaves of Boldoa purpurascens. MATERIALS AND METHODS: First, an experimental study to assess the oral acute toxicity at a dose of 2000mg/kg body weight of the extract was carried out. Potential genotoxicity of the extract was evaluated using the Ames test and the micronucleus induction assay in mouse bone marrow. In the Ames test a concentration range of 50, 100, 150, 300 and 500µg/plate was tested. In the micronucleus induction assay, doses of 500, 1000 and 2000mg/kg of body weight were tested. For completeness, since the extract contains saponins, the evaluation of the hemolytic activity, ocular and skin irritation were included. RESULTS: No signs or symptoms of toxicity were observed in the oral acute toxicity test (body weight at baseline, seven days and end of the experiment of 236.41±20.07, 256.81±30.44 and 240.02±26.16 respectively for the treated group). The hydroalcoholic extract from the leaves was not mutagenic in the Ames test, and no genotoxicity was observed in the micronucleus assay. A hemolysis test at concentration of 1mg/mL confirmed hemolytic activity, which is not a safety concern since saponins are not absorbed after oral administration. In order to evaluate the percentage of protein denaturation, the ocular irritability index was calculated. The extract was found to be irritating. Finally, skin irritability was evaluated and the irritation index was equal to zero. CONCLUSIONS: Based on the toxicological evaluation of a traditionally used hydroalcoholic extract from the leaves of Boldoa purpurascens we can confirm the safety of its oral use.


Asunto(s)
Nyctaginaceae/toxicidad , Extractos Vegetales/toxicidad , Hojas de la Planta/toxicidad , Administración Oral , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/patología , ADN Bacteriano/efectos de los fármacos , ADN Bacteriano/genética , Dermatitis por Contacto/etiología , Dermatitis por Contacto/patología , Ojo/efectos de los fármacos , Ojo/metabolismo , Proteínas del Ojo/metabolismo , Femenino , Hemólisis/efectos de los fármacos , Masculino , Ratones Endogámicos BALB C , Micronúcleos con Defecto Cromosómico/inducido químicamente , Pruebas de Micronúcleos , Mutación , Nyctaginaceae/química , Fitoterapia , Extractos Vegetales/administración & dosificación , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Plantas Medicinales , Desnaturalización Proteica , Conejos , Ratas Sprague-Dawley , Ratas Wistar , Medición de Riesgo , Pruebas de Irritación de la Piel , Solventes/química , Factores de Tiempo , Pruebas de Toxicidad Aguda
10.
Talanta ; 146: 540-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26695302

RESUMEN

Public health is threatened worldwide by counterfeit medicines. Their quality, safety and efficacy cannot be guaranteed since no quality control is performed during and/or after the manufacturing process. Characterization of these products is a very important topic. During this study a High Performance Liquid Chromatography-Photodiode Array (HPLC-PDA) and a High Performance Liquid Chromatography - Mass Spectrometry (HPLC-MS) method were developed to analyse both genuine and counterfeit samples of Cialis®. The obtained PDA and MS fingerprints were explored and modelled using unsupervised Principal Component Analysis (PCA) and supervised Partial Least Squares and its discriminant variant (PLS, PLS-DA) as well the classification methods including Soft Independent Modelling of Class Analogy (SIMCA) and the k Nearest Neighbour classifier (kNN). Both MS1 and MS2 data and data measured at 254 nm and 270 nm were used with the aim to test the potential complementarity of PDA and MS detection. First, it was checked if both groups of fingerprints can support differentiation between genuine and counterfeit medicines. Then, it was verified if the obtained multivariate models could be improved by combining information present in MS and PDA fingerprints. Survey of the models obtained for the 254 nm data, 270 nm data and 254_270 nm data combination showed that a tendency of discrimination could be observed with PLS. For the 270 nm data and 254_270 nm data combination a perfect discrimination between genuine and counterfeit medicines is obtained with PLS-DA and SIMCA. This shows that 270 nm alone performs equally well compared to 254_270 nm. For the MS1 and MS1_MS2 data perfect models were obtained using PLS-DA and kNN, indicating that the MS2 data do not provide any extra useful information to acquire the aimed distinction. When combining MS1 and 270 nm perfect models were gained by PLS-DA and SIMCA, which is very similar to the results obtained for PDA alone. These results show that both detectors have a potential to reveal chemical differences between genuine and counterfeit medicines and thus enable the construction of diagnostic models with excellent recognition. However, if a larger sample set, including more possible sources of variation, is analysed more sophisticated techniques such as MS might be necessary.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Falsificados/química , Espectrometría de Masas , Análisis de Componente Principal , Tadalafilo/análisis , Informática , Aprendizaje Automático , Tadalafilo/química
12.
J Pharm Biomed Anal ; 112: 181-9, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-25476739

RESUMEN

Counterfeit medicines pose a huge threat to public health worldwide. High amounts of counterfeit pharmaceuticals enter the European market and therefore detection of these products is essential. Attenuated Total Reflection Fourier-Transform infrared spectroscopy (ATR-FTIR) might be useful for the screening of counterfeit medicines since it is easy to use and little sample preparation is required. Furthermore, this approach might be helpful to customs to obtain a first evaluation of suspected samples. This study proposes a combination of ATR-FTIR and chemometrics to discriminate and classify counterfeit medicines. A sample set, containing 209 samples in total, was analyzed using ATR-FTIR and the obtained spectra were used as fingerprints in the chemometric data-analysis which included Principal Component Analysis (PCA), k-Nearest Neighbours (k-NN), Classification and Regression Trees (CART) and Soft Independent Modelling of Class Analogy (SIMCA). First it was verified whether the mentioned techniques are capable to distinguish samples containing different active pharmaceutical ingredients (APIs). PCA showed a clear tendency of discrimination based on the API present; k-NN, CART and SIMCA were capable to create suitable prediction models based on the presence of different APIs. However k-NN performs the least while SIMCA performs the best. Secondly, it was tested whether these three models could be expanded to discriminate between genuine and counterfeit samples as well. k-NN was not able to make the desired discrimination and therefore it was not useful. CART performed better but also this model was less suited. SIMCA, on the other hand, resulted in a model with a 100% correct discrimination between genuine and counterfeit drugs. This study shows that chemometric analysis of ATR-FTIR fingerprints is a valuable tool to discriminate genuine from counterfeit samples and to classify counterfeit medicines.


Asunto(s)
Medicamentos Falsificados/análisis , Medicamentos Falsificados/química , Análisis de Componente Principal/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos
13.
Talanta ; 123: 78-88, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24725867

RESUMEN

Counterfeit medicines are a global threat to public health. These pharmaceuticals are not subjected to quality control and therefore their safety, quality and efficacy cannot be guaranteed. Today, the safety evaluation of counterfeit medicines is mainly based on the identification and quantification of the active substances present. However, the analysis of potential toxic secondary components, like residual solvents, becomes more important. Assessment of residual solvent content and chemometric analysis of fingerprints might be useful in the discrimination between genuine and counterfeit pharmaceuticals. Moreover, the fingerprint approach might also contribute in the evaluation of the health risks different types of counterfeit medicines pose. In this study a number of genuine and counterfeit Viagra(®) and Cialis(®) samples were analyzed for residual solvent content using headspace-GC-MS. The obtained chromatograms were used as fingerprints and analyzed using different chemometric techniques: Principal Component Analysis, Projection Pursuit, Classification and Regression Trees and Soft Independent Modelling of Class Analogy. It was tested whether these techniques can distinguish genuine pharmaceuticals from counterfeit ones and if distinct types of counterfeits could be differentiated based on health risks. This chemometric analysis showed that for both data sets PCA clearly discriminated between genuine and counterfeit drugs, and SIMCA generated the best predictive models. This technique not only resulted in a 100% correct classification rate for the discrimination between genuine and counterfeit medicines, the classification of the counterfeit samples was also superior compared to CART. This study shows that chemometric analysis of headspace-GC impurity fingerprints allows to distinguish between genuine and counterfeit medicines and to differentiate between groups of counterfeit products based on the public health risks they pose.


Asunto(s)
Medicamentos Falsificados/análisis , Contaminación de Medicamentos/prevención & control , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Cromatografía de Gases y Espectrometría de Masas/métodos , Carbolinas/análisis , Carbolinas/química , Medicamentos Falsificados/química , Piperazinas/análisis , Piperazinas/química , Análisis de Componente Principal , Purinas/análisis , Purinas/química , Reproducibilidad de los Resultados , Factores de Riesgo , Citrato de Sildenafil , Sulfonamidas/análisis , Sulfonamidas/química , Tadalafilo
14.
J Ethnopharmacol ; 149(2): 438-42, 2013 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-23876596

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: To evaluate the in vitro antiplasmodial activity and cytotoxicity, and the in vivo activity of extracts and fractions from the leaves, root-bark and stem-bark of Triclisia gilletii (De Wild) Staner (Menispermaceae), used in traditional medicine against malaria. MATERIALS AND METHODS: The aqueous and 80% MeOH extracts, and a series of fractions and subfractions from the leaves, stem and root-bark of Triclisia gilletii were tested in vitro for their antiplasmodial activity against a Congolese-sensitive strain of Plasmodium falciparum, against the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum, for cytotoxicity against MRC-5 cells, and in vivo in mice infected with Plasmodium berghei berghei. RESULTS: Many samples from the three plant parts exhibited pronounced activity against the Congolese chloroquine-sensitive strain of Plasmodium falciparum with some IC50 values <0.02 µg/ml, and against the K1 strain, with some IC50 <0.25; the selectivity was higher against the Congolese strain. At oral doses of 200 and 400mg/kg body weight in infected mice, the aqueous, 80% methanol and total alkaloid extracts from the three plant parts produced more than 65% and 75% chemosuppression, respectively. The antiplasmodial activity of these three plant parts of Triclisia gilletii can at least in part be attributed to bisbenzylisoquinoline alkaloids, and supports its use for the treatment of uncomplicated malaria in traditional medicine.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/tratamiento farmacológico , Menispermaceae , Parasitemia/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Animales , Antimaláricos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cloroquina , Resistencia a Múltiples Medicamentos , Humanos , Malaria/parasitología , Ratones , Parasitemia/parasitología , Corteza de la Planta , Extractos Vegetales/farmacología , Hojas de la Planta , Raíces de Plantas , Plasmodium berghei/aislamiento & purificación , Plasmodium falciparum/efectos de los fármacos , Pirimetamina
15.
J Ethnopharmacol ; 148(2): 724-7, 2013 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-23612422

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: To evaluate the antiprotozoal activity and cytotoxicity of extracts and fractions from the leaves, root bark and stem bark of Alstonia congensis (Apocynaceae), used in traditional medicine against parasitic diseases. MATERIALS AND METHODS: The aqueous and 80% MeOH extracts, and a series of fractions and subfractions from the leaves, stem and root bark of Alstonia congensis were tested in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, Trypanosoma cruzi, Lesihamania infantum and the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum. Their cytotoxicity on MRC-5 cells (human lung fibroblasts) was evaluated as well. RESULTS: The aqueous and 80% MeOH extracts and a series of subfractions of each plant part exhibited pronounced antiprotozoal activity against the K1 strain of Plasmodium falciparum with IC50 values ranging from 2 to 5 µg/ml, and good activity against Trypanosoma brucei brucei and Trypanosoma cruzi with IC50 values ranging between 5 and 10 µg/ml. The residual 80% MeOH extract from the leaves, and the total alkaloid extract from stem and root bark were the only subfractions active against Leishmania infantum with IC50 values <10 µg/ml. None of the samples from the root bark was cytotoxic against MRC-cell lines (CC50>64 µg/ml). In general, the aqueous extract (traditional decoction) showed the highest selectivity, especially against Plasmodium falciparum. CONCLUSION: These results can partly support and justify the traditional use of these plant parts of Alstonina congensis as raw materials for the preparation of traditional remedies to treat parasitic diseases such as malaria and trypanosomiasis.


Asunto(s)
Alstonia/química , Antiprotozoarios/farmacología , Extractos Vegetales/farmacología , Antiprotozoarios/química , Línea Celular , Etnofarmacología/métodos , Fibroblastos/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Leishmania infantum/efectos de los fármacos , Pulmón/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria/métodos , Fitoterapia/métodos , Extractos Vegetales/química , Plasmodium falciparum/efectos de los fármacos , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos
16.
Qual Life Res ; 22(6): 1295-304, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22847189

RESUMEN

PURPOSE: Individuals with serious medical conditions can perceive their health status as good. This might be explained by the symptomatology inherent to the condition. Research in this respect is scarce. Congenital heart disease (CHD) is a spectrum of mild, moderate, and complex heart defects, representing more benign and severe chronic conditions. We investigated (1) symptomatology (i.e., symptom frequency and symptom distress) of CHD patients; (2) the extent to which symptomatology was independently related to perceived health; and (3) the relative importance of individual symptoms for perceived health. METHODS: A secondary data analysis on two separate patient samples (629 Belgian and 1,109 Dutch patients) was conducted. Patients' symptomatology was measured with the TAAQOL-CHD. Perceived health was measured by the EQ-5Dvas in Belgian patients, and by a single item (EVGFP rating) of the SF-36 in Dutch patients. Linear regression analyses were performed to investigate the relationship between symptoms and perceived health, while controlling for sex, age, disease complexity, and functional status. RESULTS: The most frequently occurring symptoms were dizziness, palpitations, and nycturia. Symptom distress was associated with perceived health, independent of confounders. Symptom distress with respect to shortness of breath while walking; palpitations; and dizziness were independently related to perceived health. CONCLUSIONS: Perceived health in CHD patients is partially associated with their symptomatology. This finding underscores the possibility that differences in perceived health across patient groups with more benign and severe conditions may be caused by the different impact conditions have--in terms of symptoms--on the day-to-day life.


Asunto(s)
Indicadores de Salud , Estado de Salud , Calidad de Vida , Evaluación de Síntomas/psicología , Bélgica , Femenino , Encuestas Epidemiológicas , Cardiopatías Congénitas/etnología , Cardiopatías Congénitas/fisiopatología , Cardiopatías Congénitas/psicología , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Percepción , Análisis de Regresión , Índice de Severidad de la Enfermedad , Factores Socioeconómicos , Encuestas y Cuestionarios
17.
Phytother Res ; 27(5): 721-4, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22807273

RESUMEN

In order to investigate the potential use of Boldoa purpurascens against diabetes, the antihyperglycemic effect of an ethanol extract obtained from its leaves was evaluated at doses of 50, 100 and 200 mg/kg in rats after induction of hyperglycemia by alloxan. Insulin 5 IU/kg was used as positive control and NaCl 0.9% as negative control. A similar experiment was performed with the aqueous extract used at doses of 50 and 100 mg/kg using metformin at a dose of 50mg/kg as positive control. Statistical analysis was carried using the Kruskal-Wallis test with an interval of trust of 99%. The ethanolic and aqueous extract of B. purpurascens showed a significant decrease of blood glucose levels 72 h after administration. Phytochemical analysis of the ethanol extract showed the presence of D-pinitol, a compound known for its hypoglycemic properties. In conclusion, ethanolic as well as aqueous extracts of B. purpurascens leaves show antihyperglycemic activity, possibly due to the presence of D-pinitol and flavonoids.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Nyctaginaceae/química , Extractos Vegetales/farmacología , Animales , Glucemia/análisis , Inositol/análogos & derivados , Inositol/química , Inositol/farmacología , Masculino , Metformina/uso terapéutico , Extractos Vegetales/química , Hojas de la Planta/química , Ratas , Ratas Wistar
18.
Hum Reprod ; 27(11): 3168-78, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22926845

RESUMEN

STUDY QUESTION: How patient-centered are two included specialized endometriosis clinics relative to each other and how can they improve the patient-centeredness of their care? SUMMARY ANSWER: The validated ENDOCARE questionnaire (ECQ) reliably concluded that the adjusted overall patient-centeredness did not differ between the clinics, that each clinic was significantly more patient-centered for 2 out of 10 dimensions of patient-centered endometriosis care and that clinics 1 and 2 had to improve 8 and 13 specific care aspects, respectively. WHAT IS KNOWN ALREADY: Patient-centered endometriosis care is essential to high-quality care and is defined by 10 dimensions. The ECQ was developed, validated and proved to be reliable in a European setting of self-reported endometriosis patients but had not yet been used at a clinic level for quality management. STUDY DESIGN, SIZE, DURATION: A cross-sectional survey was disseminated in 2011 to all 514 women diagnosed with endometriosis during a laparoscopy indicated for pain and/or infertility during a retrospective 2-year period (2009-2010) in two university clinics from two different European countries. PARTICIPANTS/MATERIALS, SETTING, METHODS: In total 337 patients completed the ECQ (216 and 121 per clinic). Respondents had a mean age of 34.3 years. Three in four reported a surgical diagnosis of moderate or severe endometriosis and the majority reported surgical treatment by a multidisciplinary team. The ECQ assessed the 10 dimensions of patient-centeredness, more specifically whether the health-care performance, as perceived by patients, measured up to what is important to patients in general. MAIN RESULTS: The ECQ was completed by 337 respondents (response rate = 65.6%). Reliability and validity of the ECQ for use on clinic level were confirmed. Clinics did not differ in overall mean importance scores; importance rankings of the ECQ dimensions were almost identical. The overall patient-centeredness scores (PCS), adjusted for education level, did not discriminate between the clinics. However, the adjusted PCS for the dimensions 'clinic staff' and 'technical skills' were significantly better in clinic 1, whereas the dimensions 'physical comfort' and 'access to care' were significantly better in clinic 2. There were 8 (clinic 1) and 13 (clinic 2) targets identified for joint and cross-clinic improvement. LIMITATIONS, REASONS FOR CAUTION: Response rates were relatively high. Recall bias was the most important limitation and research in more clinics is needed to define the statistical discriminative value of the ECQ. WIDER IMPLICATIONS OF THE FINDINGS: European endometriosis clinics can use the validated ECQ for reliable assessment of their 'patient-centeredness', for comparison with others and for setting specific targets to improve the patient-centeredness of their endometriosis care, to plan interventions, and to evaluate their effectiveness. STUDY FUNDING/COMPETING INTEREST: This work was funded by KU Leuven and European Network of Endometriosis (ENE), supported by the European Commission (Public Health Executive Agency). No competing interests are declared.


Asunto(s)
Endometriosis/terapia , Medicina de Precisión/métodos , Indicadores de Calidad de la Atención de Salud , Adulto , Actitud Frente a la Salud , Bélgica , Estudios Transversales , Endometriosis/diagnóstico , Endometriosis/fisiopatología , Endometriosis/cirugía , Femenino , Hospitales Universitarios , Humanos , Países Bajos , Servicio Ambulatorio en Hospital , Satisfacción del Paciente , Mejoramiento de la Calidad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
19.
J Ethnopharmacol ; 142(3): 620-6, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22609154

RESUMEN

AIM OF THE STUDY: To evaluate the antidiarrhoeal properties of Alstonia congensis leaves claimed to be effective for the treatment of diarrhoea by traditional healers during our ethnopharmacological investigation conducted in Kinshasa, Democratic Republic of Congo. MATERIALS AND METHODS: The aqueous extract (decoction), and the 80% hot methanol extract (Soxhlet extraction) were obtained. This last extract was fractionated. The antidiarrhoeal activity was evaluated using castor oil and magnesium sulphate-induced diarrhoea in animals. The potential antibacterial activity of all samples was also assessed in vitro. RESULTS: At all oral doses of 100 and 200 mg/kg body weight, all A. congensis samples showed significant and dose-dependent antidiarrhoeal activity in treated Wistar rats characterised by significant increase of onset time and decrease of all other diarrhoeal parameters at various degrees compared to untreated groups in both models. At the highest oral dose of 200 mg/kg bodyweight, the 80% hot methanol and aqueous extracts produced 79.8 ± 2.1% and 78.6 ± 0.5%, and 75.0 ± 2.1% and 71.4 ± 2.1% inhibition of defecation and diarrhoea respectively against castor oil-induced diarrhoea, and 75.0 ± 1.2% and 73.3±1.2% inhibition of diarrhoea respectively against magnesium sulphate-induced diarrhoea. The 80% hot methanol and aqueous detannified extracts showed low activity (42-47% inhibition of defecation and/or diarrhoea in both tests) suggesting that tannins may be responsible for the observed activity. At the same oral doses, the total alkaloid extract, the chloroform soluble fraction rich in alkaloids, the 80% methanol and the alkaline aqueous soluble subfractions produced more than 50% inhibition of defecation and/or diarrhoea in both tests. From the antibacterial testing in vitro, results indicated that all A. congensis samples exhibited an antibacterial activity mainly against bacteria implicated in diarrhoea with MIC and MBC values in the range of 15.6-500 µg/ml. The most active samples were the aqueous (decoction) and the 80% hot methanol dried extracts, the chloroform subfraction rich in alkaloids and the total alkaloid extract (MIC: 15.7-125 µg/ml, MBC: 31.2-250 µg/ml). Proteus varibilis was found to be the most resistant microorganism. CONCLUSION: These reported results can partly support and justify the traditional use of extracts from Alstonia congensis leaves for the treatment of diarrhoea in tradittional medicine.


Asunto(s)
Alstonia , Antibacterianos/uso terapéutico , Antidiarreicos/uso terapéutico , Diarrea/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Animales , Antibacterianos/farmacología , Antidiarreicos/farmacología , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Aceite de Ricino , Diarrea/inducido químicamente , Sulfato de Magnesio , Metanol/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Hojas de la Planta/química , Ratas , Ratas Wistar , Solventes/química
20.
J Ethnopharmacol ; 141(1): 301-8, 2012 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-22394563

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The antiprotozoal and cytotoxic activity of the aqueous extracts from 33 medicinal plants, used by traditional healers for the treatment of various parasitic diseases and collected after an ethnopharmacological inventory conducted in the Bolongo area, Bandundu province in DR Congo, was evaluated. MATERIALS AND METHODS: Decoctions were prepared, lyophilized and evaluated for in vitro antiprotozoal activity against Trypanosoma b. brucei, Trypanosoma cruzi, Leishmania infantum, and the chloroquine- and pyrimethamine-resistant K1 strain of Plasmodium falciparum. Cytotoxicity against MRC-5 cells was included to assess selectivity of activity. RESULTS: Most of the tested extracts exhibited pronounced (IC(50)≤5µg/ml) or good (5

Asunto(s)
Antiprotozoarios/farmacología , Etnofarmacología , Extractos Vegetales/farmacología , Antimaláricos/farmacología , Antiprotozoarios/aislamiento & purificación , Antiprotozoarios/uso terapéutico , Antiprotozoarios/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , República Democrática del Congo , Relación Dosis-Respuesta a Droga , Humanos , Concentración 50 Inhibidora , Leishmania infantum/efectos de los fármacos , Medicinas Tradicionales Africanas , Pruebas de Sensibilidad Parasitaria , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad , Plantas Medicinales , Plasmodium falciparum/efectos de los fármacos , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA