RESUMEN
In this study, the thermoluminescence (TL) characteristics of Ag-doped and undoped lithium tetraborate (Li2 B4 O7 , LTB) materials, grown using the Czochralski method, were reported. The TL properties of LTB:Ag, such as glow curve structure, dose response, fading and reproducibility, were investigated. The glow curve of the Li2 B4 O7 :Ag single crystal consists of four peaks located at approximately 75, 130, 190 and 275°C; in undoped LTB, the single crystal shows a broad glow curve with peaks at 65, 90, 125, 160 and 190°C using a heating rate of 5°C/s in the 50-350°C temperature region. The high temperature peak of Ag-doped sample at 275°C has a nonlinear dose response within the range from 33 mGy to 9 Gy. There is a linear response in the range of 33-800 mGy; after which, a sublinear region appears up to 9 Gy for Ag-doped LTB single crystal. For undoped single crystal, the dose response is supralinear for low doses and linear for the region between 1 and 9 Gy. The thermal fading ratio of the undoped material is almost 60% for the high temperature peak after 7 days. Ag-doped LTB single crystal exhibits different behaviour over a period of 7 days.
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Boratos/química , Mediciones Luminiscentes/métodos , Plata/química , Dosimetría Termoluminiscente/métodos , Cristalización , Reproducibilidad de los Resultados , TemperaturaRESUMEN
OBJECTIVE: To evaluate long-term (up to 5.5 years) safety, seizure reduction, and maintenance of efficacy of the antiepileptic drug (AED) lacosamide as adjunctive treatment in an open-label extension trial (SP774; ClinicalTrials.gov: NCT00515619). METHODS: Three hundred and seventy-six adults with partial-onset seizures taking 1-3 AEDs enrolled following completion of a double-blind trial of adjunctive lacosamide. During open-label treatment, dosage of lacosamide (100-800 mg/day) and/or concomitant AEDs could be adjusted to optimize tolerability and seizure control. RESULTS: Kaplan-Meier estimates of patient retention were 74.5% at 12 months, 52.9% at 36 months, and 40.6% at 60 months; median open-label treatment duration was 1183 days (~3.2 years). The most frequently reported treatment-emergent adverse events were dizziness (24.2%), headache (14.4%), diplopia (13.8%), and nasopharyngitis (13.8%); 9.0% of patients discontinued due to adverse events, most commonly dizziness (1.3%). Median percent reduction in 28-day seizure frequency from baseline of the double-blind trial was 49.9% overall, 55.4% for 1-year completers, and 62.3% for 3-year completers. Overall, 50.0% of patients were considered ≥50% responders (achieved ≥50% reduction in 28-day seizure frequency); 55.9% of 1-year completers and 63.0% of 3-year completers were ≥50% responders. CONCLUSION: In eligible patients who entered the open-label extension trial, lacosamide was generally well tolerated. For most patients within each yearly completer cohort, seizure reduction was maintained over time.
RESUMEN
Interpretation of high resolution images provided by localization-based microscopy techniques is a challenge due to imaging artefacts that can be categorized by their origin. They can be introduced by the optical system, by the studied sample or by the applied algorithms. Some artefacts can be eliminated via precise calibration procedures, others can be reduced only below a certain value. Images studied both theoretically and experimentally are qualified either by pattern specific metrics or by a more general metric based on fluorescence correlation spectroscopy.
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Artefactos , Microscopía Fluorescente/métodos , Algoritmos , CalibraciónRESUMEN
Medicated chewing gum tablets were prepared and evaluated as an oral drug delivery system. The morphology and surface free energy of the components were characterized, and the tablets were prepared by direct compression with an instrumented eccentric tableting machine. The compressibility, the porosity and the texture of the tablets were investigated and the dissolution of the active pharmaceutical ingredient (caffeine) from them was tested with a specially-developed method. Cafosa gum base is a co-processed product which is compressible. Because of the sticking of the tablets to the punches and the high friction that arises during ejection from the die, the use of lubricants and suitable (e.g. Teflon-coated) punches is necessary on a production scale. For this purpose, magnesium stearate with high specific surface area was applied. The release of caffeine in response to the mechanical effect applied proved to be rapid and quantitative and the profile closely obeyed the Korsmeyer-Peppas equation, which is valid in the case of matrix systems. Medicated chewing gum tablets can be used as matrix tablets for oral pharmaceutical administration.
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Comprimidos/química , Administración Oral , Química Farmacéutica/métodos , Goma de Mascar , Sistemas de Liberación de Medicamentos/métodos , Lubricantes/química , Solubilidad , Ácidos Esteáricos/química , Tecnología Farmacéutica/métodosRESUMEN
Epilepsy and mental retardation limited to females (EFMR), caused by PCDH19 mutations, has a variable clinical expression that needs further exploration. Onset of epilepsy may be provoked by fever and can resemble Dravet syndrome. Furthermore, transmitting males have no seizures, but are reported to have rigid personalities suggesting possible autism spectrum disorders (ASD). Therefore, this study aimed to determine the phenotypic spectrum associated with PCDH19 mutations in Dravet-like and EFMR female patients and in males with ASD. We screened 120 females suffering from Dravet-like epilepsy, 136 females with EFMR features and 20 males with ASD. Phenotypes and genotypes of the PCDH19 mutation carriers were compared with those of 125 females with EFMR reported in the literature. We report 15 additional patients with a PCDH19 mutation. Review of clinical data of all reported patients showed that the clinical picture of EFMR is heterogeneous, but epilepsy onset in infancy, fever sensitivity and occurrence of seizures in clusters are key features. Seizures remit in the majority of patients during teenage years. Intellectual disability and behavioural disturbances are common. Fifty percent of all mutations are missense mutations, located in the extracellular domains only. Truncating mutations have been identified in all protein domains. One ASD proband carried one missense mutation predicted to have a deleterious effect, suggesting that ASD in males can be associated with PCDH19 mutations.
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Cadherinas/genética , Trastornos Generalizados del Desarrollo Infantil/epidemiología , Trastornos Generalizados del Desarrollo Infantil/genética , Epilepsia/epidemiología , Epilepsia/genética , Mutación/fisiología , Adolescente , Cadherinas/fisiología , Niño , Trastornos Generalizados del Desarrollo Infantil/complicaciones , Preescolar , Estudios de Cohortes , Epilepsias Mioclónicas/epidemiología , Epilepsias Mioclónicas/genética , Epilepsia/complicaciones , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Discapacidad Intelectual/complicaciones , Discapacidad Intelectual/epidemiología , Discapacidad Intelectual/genética , Masculino , Penetrancia , Protocadherinas , Caracteres Sexuales , SíndromeRESUMEN
The topic of this article is the compression physics of different gum bases which can be used to prepare chewing gum tablets by direct compression. Three different gum bases, Pharmagum(®) C, M and S, were tested alone and in different combinations. The preparations were compressed with a Korsch EK0 eccentric tableting machine at compression forces of 5, 7.5, 10, 12.5 and 15 kN. The compression and breaking processes and the physical parameters of the tablets were investigated. The results revealed that increase of the compression force did not significantly change the studied parameters of the tablets.
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Ácido Ascórbico/química , Polímeros/química , Comprimidos/química , Química Farmacéutica/métodos , Goma de Mascar , Tecnología Farmacéutica/métodosRESUMEN
We studied the early vegetation dynamics in former croplands (sunflower and cereal fields) sown with a low-diversity seed mixture (composed of 2 native grass species) in Egyek-Pusztakócs, Hortobágy National Park, East-Hungary. The percentage cover of vascular plants was recorded in 4 permanent plots per field on 7 restored fields between 2006 and 2009. Ten aboveground biomass samples per field were also collected in June in each year. We addressed two questions: (i) How do seed sowing and annual mowing affect the species richness, biomass and cover of weeds? (ii) How fast does the cover of sown grasses develop after seed sowing? Weedy species were characteristic in the first year after sowing. In the second and third year their cover and species richness decreased. From the second year onwards the cover of perennial grasses increased. Spontaneously immigrating species characteristic to the reference grasslands were also detected with low cover scores. Short-lived weeds were suppressed as their cover and biomass significantly decreased during the study. The amount of litter and sown grass biomass increased progressively. However, perennial weed cover, especially the cover of Cirsium arvense increased substantially. Our results suggest that grassland vegetation can be recovered by sowing low diversity mixtures followed up by yearly mowing. Suppression of perennial weed cover needs more frequent mowing (multiple times a year) or grazing.
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Biodiversidad , Biomasa , Malezas , Semillas , Biodegradación Ambiental , Grano Comestible , Helianthus , Hungría , PoaceaeRESUMEN
The authors summarize the pathomechanism of the myelination process, the clinical, radiological and the genetical aspects of the leukodystrophies, as in 18q deletion syndrome, adrenoleukodysrtophy, metachromatic leukodystrophy, Pelizaeus-Merzbacher leukodystrophy, Alexander disease and olivo-ponto-cerebellar atrophy (OPCA).
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Encéfalo/patología , Cromosomas Humanos Par 18 , Eliminación de Gen , Leucodistrofia Metacromática/diagnóstico , Leucodistrofia Metacromática/genética , Imagen por Resonancia Magnética , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/genética , Adulto , Enfermedad de Alexander/diagnóstico , Enfermedad de Alexander/genética , Encéfalo/diagnóstico por imagen , Enfermedad de Canavan/diagnóstico , Enfermedad de Canavan/genética , Preescolar , Femenino , Humanos , Lactante , Leucodistrofia Metacromática/diagnóstico por imagen , Masculino , Enfermedad de Pelizaeus-Merzbacher/diagnóstico , Enfermedad de Pelizaeus-Merzbacher/genética , Radiografía , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
Neutral theory of species assembly means that species assembly is governed by stochastic dispersal processes and fluctuations in established populations. An alternative theory suggests that assembly is strongly determined by functional trait filtering governed by abiotic and biotic filtering selecting species from the local species pool. To test these assumptions, in the current paper we analysed vegetation changes in the first 12 years of succession after heavy goose grazing on acidic sand. With trait-based analyses using permanent plots we addressed the following hypotheses: (i) High fluctuations in the trait values are typical in the first years; later a temporally divergent change in the trait patterns of sites with different vertical position became characteristic. (ii) In the functional diversity of regenerative and vegetative traits we expected different temporal patterns. We confirmed the first hypothesis, as in the first few years most traits displayed high fluctuations with no clear patterns. Our findings weakly supported the second hypothesis; while there were distinct patterns detected in the functional richness of traits, functional divergence and evenness displayed no clear distinctive patterns. We can conclude that both trait neutrality and filtering effects operate in the vegetation changes of the first period of secondary succession.
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Biodiversidad , Ecosistema , Clima , Pradera , Plantas , Procesos EstocásticosRESUMEN
PURPOSE: To describe clinical characteristics and lateralizing value of postictal automatisms in patients with temporal lobe epilepsy (TLE). METHODS: One hundred and ninety-three videotaped seizures of 55 consecutive patients with refractory TLE and postoperatively seizure-free outcome were analyzed. Ictal as well as postictal (manual, oral and speech) automatisms were monitored. RESULTS: Thirty-four (62%) of the 55 patients showed PA at least once during their seizures. Postictal automatism was observed in 70 (36%) attacks as manual (21%), oral (13%) or speech (9%) automatisms. Fifteen seizures contained a combination of two different postictal automatisms. The presence of postictal oral automatisms did not lateralize the seizure onset zone (p=0.834). Speech automatisms (repetitive verbal behavior) occurred more frequently after left-sided seizures (p=0.002). Postictal unilateral manual automatism showed no lateralizing value occurring by the ipsilateral hand in 10 and the contralateral upper limb in 6 seizures (p=0.454). CONCLUSION: : Postictal automatism is a relatively frequent phenomenon in TLE. Postictal speech automatism lateralizes the seizure onset zone to the left hemisphere. Our observation can help the presurgical evaluation of TLE because verbal perseveration frequently occurs spontaneously, even in seizures without appropriate postictal language testing.
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Automatismo , Epilepsia del Lóbulo Temporal/fisiopatología , Lateralidad Funcional , Convulsiones/fisiopatología , Adolescente , Adulto , Edad de Inicio , Niño , Epilepsia del Lóbulo Temporal/cirugía , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Grabación en VideoRESUMEN
OBJECTIVE: To describe clinical characteristics and lateralizing value of peri-ictal electrode manipulation automatism (EMA) in patients with temporal lobe epilepsy (TLE) and compare our data with ictal manual automatisms described in the literature. METHODS: Two-hundred and five videotaped seizures of 55 consecutive patients with refractory TLE and postoperatively seizure-free outcome were analyzed and EMA (tugging, scratching or adjusting the electrodes and cables) were monitored. RESULTS: Twenty-eight (51%) patients showed EMA during 47 (23%) seizures. Ictal start was noted in 22 seizures and in 19/22 cases EMA finished before the end of seizure. Ictal EMAs were always associated with automotor seizure components. During 25 seizures, exclusively postictal EMAs were observed. Electrode manipulation was presented during 24/112 left-sided and 23/93 right-sided seizures (p = 0.742). Peri-ictal EMA was unilateral (completed by one hand) in 24/47 seizures (10 ictal, 14 postictal); it was done by the hand ipsilateral to the seizure onset zone in 17/24 and by contralateral hand in 7/24 cases (p = 0.064). We observed concomitant contralateral dystonic posturing during 3/10 seizures with unilateral ictal EMA. Unilateral hand automatism, temporally independent from the EMA appeared in 30 (64%) of the 47 seizures. CONCLUSION: Peri-ictal EMA is a frequent phenomenon but shows no lateralizing value in TLE. The mechanism of EMA is in many ways dissimilar from that of earlier described manual automatisms.
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Automatismo , Electroencefalografía/instrumentación , Epilepsia del Lóbulo Temporal/fisiopatología , Convulsiones/fisiopatología , Adolescente , Adulto , Niño , Electrodos , Epilepsia del Lóbulo Temporal/cirugía , Humanos , Persona de Mediana Edad , Grabación en VideoRESUMEN
Leucine-rich glioma-inactivated (LGI) protein was first thought to have a suppressor effect in the formation of some cancers. Developments in physiology and medicine made it possible to characterize the function of the LGI protein family and its crucial role in different conditions more precisely. These proteins play an important role in synaptic transmission, and dysfunction may cause hyperexcitability. Genetic mutation of LGI1 was confirmed to be the cause of autosomal dominant lateral temporal lobe epilepsy in humans. The LGI2 mutation was identified in benign familial juvenile epilepsy in Lagotto Romagnolo (LR) dogs. Cats with familial spontaneous temporal lobe epilepsy have been reported, and the etiology might be associated with LGI protein family dysfunction. In addition, an autoimmune reaction against LGI1 was detected in humans and cats with limbic encephalitis. These advances prompted a review of LGI protein function and its role in different seizure disorders.
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Epilepsia/etiología , Proteínas del Tejido Nervioso/fisiología , Animales , Enfermedades de los Gatos/etiología , Enfermedades de los Gatos/genética , Gatos , Enfermedades de los Perros/etiología , Enfermedades de los Perros/genética , Perros , Epilepsia/genética , Epilepsia/veterinaria , Humanos , Péptidos y Proteínas de Señalización Intracelular , Encefalitis Límbica/inmunología , Encefalitis Límbica/veterinaria , Mutación , Proteínas del Tejido Nervioso/genética , Proteínas/genética , Proteínas/inmunología , Proteínas/fisiología , Transmisión Sináptica/fisiologíaRESUMEN
This paper presents a new technique for the automatic model-based segmentation of three-dimensional (3-D) objects from volumetric image data. The development closely follows the seminal work of Taylor and Cootes on active shape models, but is based on a hierarchical parametric object description rather than a point distribution model. The segmentation system includes both the building of statistical models and the automatic segmentation of new image data sets via a restricted elastic deformation of shape models. Geometric models are derived from a sample set of image data which have been segmented by experts. The surfaces of these binary objects are converted into parametric surface representations, which are normalized to get an invariant object-centered coordinate system. Surface representations are expanded into series of spherical harmonics which provide parametric descriptions of object shapes. It is shown that invariant object surface parametrization provides a good approximation to automatically determine object homology in terms of sets of corresponding sets of surface points. Gray-level information near object boundaries is represented by 1-D intensity profiles normal to the surface. Considering automatic segmentation of brain structures as our driving application, our choice of coordinates for object alignment was the well-accepted stereotactic coordinate system. Major variation of object shapes around the mean shape, also referred to as shape eigenmodes, are calculated in shape parameter space rather than the feature space of point coordinates. Segmentation makes use of the object shape statistics by restricting possible elastic deformations into the range of the training shapes. The mean shapes are initialized in a new data set by specifying the landmarks of the stereotactic coordinate system. The model elastically deforms, driven by the displacement forces across the object's surface, which are generated by matching local intensity profiles. Elastic deformations are limited by setting bounds for the maximum variations in eigenmode space. The technique has been applied to automatically segment left and right hippocampus, thalamus, putamen, and globus pallidus from volumetric magnetic resonance scans taken from schizophrenia studies. The results have been validated by comparison of automatic segmentation with the results obtained by interactive expert segmentation.
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Imagen por Resonancia Magnética/métodos , Modelos Neurológicos , Algoritmos , Encéfalo/patología , Elasticidad , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Reproducibilidad de los Resultados , Esquizofrenia/diagnóstico , Propiedades de SuperficieRESUMEN
Hypochondriacal personality disorder is identified as a separate condition by cluster analysis of data from a structured interview for assessing personality disorders, the Personality Assessment Schedule. Close examination of the patients identified as having hypochondriacal personality disorder suggests that they have common characteristics, including excessive preoccupation with the maintenance of health, distorted perception of minor symptoms so that they are elevated to the status of major disease, and frequent medical consultations and disciplines fringing on medicine. In a study of 1000 psychiatric patients 2.5% were found to have the disorder, most frequently among the affective psychoses.
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Hipocondriasis/diagnóstico , Trastornos de la Personalidad/diagnóstico , Trastornos de Adaptación/clasificación , Trastornos de Adaptación/diagnóstico , Trastornos de Adaptación/psicología , Adulto , Trastornos Psicóticos Afectivos/clasificación , Trastornos Psicóticos Afectivos/diagnóstico , Trastornos Psicóticos Afectivos/psicología , Anciano , Deluciones/clasificación , Deluciones/diagnóstico , Deluciones/psicología , Femenino , Humanos , Hipocondriasis/clasificación , Hipocondriasis/psicología , Masculino , Persona de Mediana Edad , Trastornos Neuróticos/clasificación , Trastornos Neuróticos/diagnóstico , Trastornos Neuróticos/psicología , Determinación de la Personalidad/estadística & datos numéricos , Trastornos de la Personalidad/clasificación , Trastornos de la Personalidad/psicología , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Psicometría , Esquizofrenia/clasificación , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Trastornos Somatomorfos/clasificación , Trastornos Somatomorfos/diagnóstico , Trastornos Somatomorfos/psicologíaRESUMEN
This paper describes a new model-based segmentation technique combining desirable properties of physical models (snakes), shape representation by Fourier parametrization, and modelling of natural shape variability. Flexible parametric shape models are represented by a parameter vector describing the mean contour and by a set of eigenmodes of the parameters characterizing the shape variation. Usually the segmentation process is divided into an initial placement of the mean model and an elastic deformation restricted to the model variability. This, however leads to a separation of biological variation due to a global similarity transform from small-scale shape changes originating from elastic deformations of the normalized model contours only. The performance can be considerably improved by building shape models normalized with respect to a small set of stable landmarks (AC-PC in our application) and by explaining the remaining variability among a series of images with the model flexibility. This way the image interpretation is solved by a new coarse-to-fine segmentation procedure based on the set of deformation eigenmodes, making a separate initialization step unnecessary. Although straightforward, the extension to 3-D is severely impeded by difficulties arising during the generation of a proper surface parametrization for arbitrary objects with spherical topology. We apply a newly developed surface parametrization which achieves a uniform mapping between object surface and parameter space. The 3-D procedure is demonstrated by segmenting deep structures of the human brain from MR volume data.
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Encéfalo/anatomía & histología , Análisis de Fourier , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Anatomía Transversal , Núcleo Caudado/anatomía & histología , Simulación por Computador , Globo Pálido/anatomía & histología , HumanosRESUMEN
We investigated the nature of preictal subjective phenomena and whether they had any effect on the seizure frequency in 95 adult patients with medial temporal lobe epilepsy. Seventy-three (77%) patients indicated that they experienced seizure-provoking factors. Ten patients (11%) had prodromas independent of auras, while auras occurred in 89%. Forty-four patients (46%) reported that that they had tried to stop their seizures in the presence of prodroma or aura and this action had resulted in success at least once. Twenty-one patients (22%) regularly tried to stop their seizures because this effort was often successful according to their interpretation. Patients who reported that they could frequently inhibit their seizures had 1.8 +/- 1.6 seizures/month, a significantly lower mean seizure frequency than those 74 patients who did not do it regularly (4.6 +/- 4.8 seizures/month, P<0.001). Patients who reported regular experience in inhibiting intentionally their seizures more often had affective (P=0.05) and vertiginous auras (P<0.01) as well as isolated auras (P<0.05). Patients who experienced provoking factors showed the same seizure frequency as those who did not. Our results suggest that intentional seizure inhibition had an impact on the severity of drug-resistant epilepsy.
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Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Epilepsia del Lóbulo Temporal/prevención & control , Convulsiones/tratamiento farmacológico , Convulsiones/prevención & control , Adolescente , Adulto , Anticonvulsivantes/uso terapéutico , Distribución de Chi-Cuadrado , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Rare earth doped oxide, phosphate, etc. are radioluminescent phosphors that have a broad application in X ray imaging, in luminescent screens, image transformers and in fluorescent lamp manufacturing. Some of them have interesting thermoluminescence features as well, which makes the phosphors applicable also in dosimetry. Two of these materials are Sr3(PO4)2 and BaFCl activated with europium. The general radioluminescence (RL) and thermoluminescence (TL) characteristics of these materials was investigated earlier and the preliminary results have already been published elsewhere. The aim of the present work is to investigate the interesting properties of these phosphors mainly from a dosimetric point of view (sensitivity, dose dependence, etc.).
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Dosimetría Termoluminiscente/métodos , Partículas beta , Europio/química , Europio/efectos de la radiación , Rayos gamma , Calor , Mediciones Luminiscentes , Metales de Tierras Raras/química , Metales de Tierras Raras/efectos de la radiación , Fosfatos/química , Fosfatos/efectos de la radiación , Radioquímica , Espectrofotometría , Estroncio/química , Estroncio/efectos de la radiación , Rayos XRESUMEN
In a prospective epidemiological study of 23,792 singleton pregnancies the authors investigated the relationship between elevated maternal serum alfa-fetoprotein level and the risk of pathological pregnancy outcome. It has been found that elevated level of maternal alfa-fetoprotein (above 2.5 MoM) is associated with a higher risk of pathological pregnancies and an increased risk of subsequent fetal death. Physicians should be aware of the benefits of the maternal alpha-fetoprotein screening not only in the context of prenatal detection of congenital defects, but also in early identification of increased risk of certain obstetric complications.