286 resultados para unspecific monooxygenase
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A 20-year old Swiss Warmblood mare was referred to the Swiss Institute of Equine Medicine with a history of poor performance, coughing and ataxia and hindlimb weakness which progressed to recumbency. Lung auscultation revealed pronounced wheezing, blood work showed signs of chronic inflammation and increased bone turnover and thoracic ultrasound indicated patchy pulmonary consolidation. Cerebrospinal fluid revealed only mild, unspecific changes allowing exclusion of meningoencephalomyelitis and clinically relevant bleeding. Despite medical treatment and support in a sling the mare did not improve and was euthanized. Necropsy revealed a poorly demarcated, non-encapsulated and invasively growing mass dorsally in the musculature at the level of the forth cervical vertebra (C4) infiltrating the vertebral body and the spinal canal at the level of C1–C2. Multiple nodular, firm masses were present in all lobes of the lung and appeared to be mainly located in vessels. Histologically the masses were composed of spindle cells with marked anisocytosis, anisocaryosis, a high mitotic activity and showed invasive growth. These neoplastic cells stained positive for CD31, an endothelial cell marker, which confirmed diagnosis of a hemangiosarcoma. Definite ante mortem diagnosis of hemangiosarcoma, which is rare in horses, is challenging. Besides the vertebral localization, disseminated, locally invasive and cutaneous forms of hemangiosarcoma exist and can be either acquired or congenital. Prognosis for equine hemangiosarcoma and response to treatment are usually poor and progression of clinical signs is rapid. Vertebral hemangiosarcoma is an uncommon cause of spinal ataxia in horses.
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INTRODUCTION Erythema exsudativum multiforme majus (EEMM) and Stevens-Johnson Syndrome (SJS) are severe cutaneous reaction patterns caused by infections or drug hypersensitivity. The mechanism by which widespread keratinocyte death is mediated by the immune system in EEMM/SJS are still to be elucidated. Here, we characterized the blister cells isolated from a patient with EEMM/SJS overlap and investigated its cause. METHODS Clinical classification of the cutaneous eruption was done according to the consensus definition of severe blistering skin reactions and histological analysis. Common infectious causes of EEMM were investigated using standard clinical techniques. T cell reactivity for potentially causative drugs was assessed by lymphocyte transformation tests (LTT). Lymphocytes isolated from blister fluid were analyzed for their expression of activation markers and cytotoxic molecules using flow cytometry. RESULTS The healthy 58 year-old woman suffered from mild respiratory tract infection and therefore started treatment with the secretolytic drug Ambroxol. One week later, she presented with large palmar and plantar blisters, painful mucosal erosions, and flat atypical target lesions and maculae on the trunc, thus showing the clinical picture of an EEMM/SJS overlap (Fig. 1). This diagnosis was supported by histology, where also eosinophils were found to infiltrate the upper dermis, thus pointing towards a cutaneous adverse drug reaction (cADR). Analysis of blister cells showed that they mainly consisted of CD8+ and CD4+ T cells and a smaller population of NK cells. Both the CD8+ T cells and the NK cells were highly activated and expressed Fas ligand and the cytotoxic molecule granulysin (Fig. 2). In addition, in comparison to NK cells from PBMC, NK cells in blister fluids strongly upregulated the expression of the skin-homing chemokine receptor CCR4 (Fig 4). Surprisingly, the LTT performed on PBMCs in the acute phase was positive for Ambroxol (SI=2.9) whereas a LTT from a healthy but exposed individual did not show unspecific proliferation. Laboratory tests for common infectious causes of EEMM were negative (HSV-1/-2, M. pneumoniae, Parvovirus B19). However, 6 weeks later, specific proliferation to Ambroxol could no longer be observed in the LTT (Fig 4.).
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Human energy harvesting is envisioned as a remedy to the weight, the size, and the poor energy density of primary batteries in medical implants. The first implant to have necessarily raised the idea of a biological power supply was the pacemaker in the early 1960s. So far, review articles on human energy harvesting have been rather unspecific and no tribute has been given to the early role of the pacemaker and the cardiovascular system in triggering research in the field. The purpose of the present article is to provide an up-to-date review of research efforts targeting the cardiovascular system as an alternative energy source for active medical implants. To this end, a chronological survey of the last 14 most influential publications is proposed. They include experimental and/or theoretical studies based on electromagnetic, piezoelectric, or electrostatic transducers harnessing various forms of energy, such as heart motion, pressure gradients, and blood flow. Technical feasibility does not imply clinical applicability: although most of the reported devices were shown to harvest an interesting amount of energy from a physiological environment, none of them were tested in vivo for a longer period of time.Human energy harvesting is envisioned as a remedy to the weight, the size, and the poor energy density of primary batteries in medical implants. The first implant to have necessarily raised the idea of a biological power supply was the pacemaker in the early 1960s. So far, review articles on human energy harvesting have been rather unspecific and no tribute has been given to the early role of the pacemaker and the cardiovascular system in triggering research in the field. The purpose of the present article is to provide an up-to-date review of research efforts targeting the cardiovascular system as an alternative energy source for active medical implants. To this end, a chronological survey of the last 14 most influential publications is proposed. They include experimental and/or theoretical studies based on electromagnetic, piezoelectric, or electrostatic transducers harnessing various forms of energy, such as heart motion, pressure gradients, and blood flow. Technical feasibility does not imply clinical applicability: although most of the reported devices were shown to harvest an interesting amount of energy from a physiological environment, none of them were tested in vivo for a longer period of time.
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The correlation between cholinergic sensitivity and the level of stratification for ganglion cells was examined in the rabbit retina. As examples, we have used ON or OFF alpha ganglion cells and ON/OFF directionally selective (DS) ganglion cells. Nicotine, a cholinergic agonist, depolarized ON/OFF DS ganglion cells and greatly enhanced their firing rates but it had modest excitatory effects on ON or OFF alpha ganglion cells. As previously reported, we conclude that DS ganglion cells are the most sensitive to cholinergic drugs. Confocal imaging showed that ON/OFF DS ganglion cells ramify precisely at the level of the cholinergic amacrine cell dendrites, and co-fasciculate with the cholinergic matrix of starburst amacrine cells. However, neither ON or OFF alpha ganglion cells have more than a chance association with the cholinergic matrix. Z -axis reconstruction showed that OFF alpha ganglion cells stratify just below the cholinergic band in sublamina a while ON alpha ganglion cells stratify just below cholinergic b . The latter is at the same level as the terminals of calbindin bipolar cells. Thus, the calbindin bipolar cell appears to be a prime candidate to provide the bipolar cell input to ON alpha ganglion cells in the rabbit retina. We conclude that the precise level of stratification is correlated with the strength of cholinergic input. Alpha ganglion cells receive a weak cholinergic input and they are narrowly stratified just below the cholinergic bands.
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The cytochromes P450 (P450) comprise a superfamily of hemoproteins that function in concert with NADPH-cytochrome P450 reductase (P450-reductase) to metabolize both endogenous and exogenous compounds. Many pharmacological agents undergo phase I metabolism by this P450 and P450-reductase monooxygenase system. Phase I metabolism ensures that these highly hydrophobic xenobiotics are made more hydrophilic, and hence easier to extrude from the body. While the majority of phase I metabolism occurs in the liver, metabolism in extrahepatic organ-systems like the intestine, kidney, and brain can have important roles in drug metabolism and/or efficacy. ^ While P450-mediated phase I metabolism has been well studied, investigators have only recently begun to elucidate what physiological roles P450 may have. One way to approach this question is to study P450s that are highly or specifically expressed in extrahepatic tissues. In this project I have studied the role of a recently cloned P450 family member, P450 2D18, that was previously shown to be expressed in the rat brain and kidney, but not in the liver. To this end, I have used the baculovirus expression system to over-express recombinant P450 2D18 and purified the functional enzyme using nickel and hydroxylapatite chromatography. SDS-PAGE analysis indicated that the enzyme was purified to electrophoretic homogeneity and Western analysis showed cross-reactivity with rabbit anti-human P450 2D6. Carbon monoxide difference spectra indicated that the purified protein contained no denatured P450 enzyme; this allowed for further characterization of the substrates and metabolites formed by P450 2D18-mediated metabolism. ^ Because P450 2D18 is expressed in brain, we characterized the activity toward several psychoactive drugs including the antidepressants imipramine and desipramine, and the anti-psychotic drugs chlorpromazine and haloperidol. P450 2D18 preferentially catalyzed the N-demethylation of imipramine, desipramine, and chlorpromazine. This is interesting given the fact that other P450 isoforms form multiple metabolites from such compounds. This limited metabolic profile might suggest that P450 2D18 has some unique function, or perhaps a role in endobiotic metabolism. ^ Further analysis of possible endogenous substrates for P450 2D18 led to the identification of dopamine and arachidonic acid as substrates. It was shown that P450 2D18 catalyzes the oxidation of dopamine to aminochrome, and that the enzyme binds dopamine with an apparent KS value of 678 μM, a value well within reported dopamine concentration in brain dopaminergic systems. Further, it was shown that P450 2D18 binds arachidonic acid with an apparent KS value of 148 μM, and catalyzes both the ω-hydroxylation and epoxygenation of arachidonic acid to metabolites that have been shown to have vasoactive properties in brain, kidney, and heart tissues. These data provide clues for endogenous roles of P450 within the brain, and possible involvement in the pathogenesis of Parkinson's disease. ^
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Sulphonated anthraquinones are precursors of many synthetic dyes and pigments, recalcitrant to biodegradation and thus not eliminated by classical wastewater treatments. In the development of a phytotreatment to remove sulphonated aromatic compounds from dye and textile industrial effluents, it has been shown that rhubarb (Rheum rabarbarum) and common sorrel (Rumex acetosa) are the most efficient plants. Both species, producing natural anthraquinones, not only accumulate, but also transform these xenobiotic chemicals. Even if the precise biochemical mechanisms involved in the detoxification of sulphonated anthraquinones are not yet understood, they probably have cross talks with secondary metabolism, redox processes and plant energy metabolism. The aim of the present study was to investigate the possible roles of cytochrome P450 monooxygenases and peroxidases in the detoxification of several sulphonated anthraquinones. Both plant species were cultivated in a greenhouse under hydroponic conditions, with or without sulphonated anthraquinones. Plants were harvested at different times and either microsomal or cytosolic fractions were prepared. The monooxygenase activity of cytochromes P450 toward several sulphonated anthraquinones was tested using a new method based on the fluorimetric detection of oxygen consumed during cytochromes P450-catalysed reactions. The activity of cytosolic peroxidases was measured by spectrophotometry, using guaiacol as a substrate. A significant activity of cytochromes P450 was detected in rhubarb leaves, while no (rhizome) or low (petioles and roots) activity was found in other parts of the plants. An induction of this enzyme was observed at the beginning of the exposition to sulphonated anthraquinones. The results also indicated that cytochromes P450 were able to accept as substrate the five sulphonated anthraquinones, with a higher activity toward AQ-2,6-SS (0.706 nkat/mg protein) and AQ-2-S (0.720 nkat/mg protein). An activity of the cytochromes P450 was also found in the leaves of common sorrel (1.212 nkat/mg protein (AQ-2,6-SS)), but no induction of the activity occurred after the exposition to the pollutant. The activity of peroxidases increased when rhubarb was cultivated in the presence of the five sulphonated anthraquinones (0.857 nkat/mg protein). Peroxidase activity was also detected in the leaves of the common sorrel (0.055 nkat/mg protein), but in this plant, no significant difference was found between plants cultivated with and without sulphonated anthraquinones. Results indicated that the activity of cytochromes P450 and peroxidases increased in rhubarb in the presence of sulphonated anthraquinones and were involved in their detoxification mechanisms. These results suggest the existence in rhubarb and common sorrel of specific mechanisms involved in the metabolism of sulphonated anthraquinones. Further investigation should be performed to find the next steps of this detoxification pathway. Besides these promising results for the phytotreatment of sulphonated anthraquinones, it will be of high interest to develop and test, at small scale, an experimental wastewater treatment system to determine its efficiency. On the other hand, these results reinforce the idea that natural biodiversity should be better studied to use the most appropriate species for the phytotreatment of a specific pollutant.
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Sulphonated anthraquinones are precursors of many synthetic dyes and pigments, recalcitrant to biodegradation, and thus contaminating many industrial effluents and rivers. In the development of a phytotreatment to remove sulphonated aromatic compounds, rhubarb (Rheum rhaponticum), a plant producing natural anthraquinones, as well as maize (Zea mays) and celery (Apium graveolens), plants not producing anthraquinones, were tested for their ability to metabolise these xenobiotics. Plants were cultivated under hydroponic conditions, with or without sulphonated anthraquinones, and were harvested at different times. Either microsomal or cytosolic fractions were prepared. The monooxygenase activity of cytochromes P450 towards several sulphonated anthraquinones was tested using a new method based on the fluorimetric detection of oxygen consumed during cytochromes P450-catalysed reactions. The activity of cytosolic peroxidases was measured by spectrophotometry, using guaiacol as a substrate. Results indicated that the activity of cytochromes P450 and peroxidases significantly increased in rhubarb plants cultivated in the presence of sulphonated anthraquinones. A higher activity of cytochromes P450 was also detected in maize and celery exposed to the pollutants. In these two plants, a peroxidase activity was also detected, but without a clear difference between the control plants and the plants exposed to the organic contaminants. This research demonstrated the existence in rhubarb, maize and celery of biochemical mechanisms involved in the metabolism and detoxification of sulphonated anthraquinones. Taken together, results confirmed that rhubarb might be the most appropriate plant for the phytotreatment of these organic pollutants.
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Botryoid odontogenic cysts (BOC) are considered to be rare polycystic variants of lateral periodontal cysts characterized by a multilocular growth pattern. The most frequent location of BOC is the mandible, predominantly the premolar-canine area, followed by the anterior region of the maxilla. The cyst shows a slight female predilection. This case report of a BOC demonstrates a treatment with initial fenestration and decompression of the cyst in order to prevent damage to adjacent structures such as the inferior alveolar nerve. The present case report emphasizes the importance of accurate clinical, radiographic, and histologic diagnostic procedures of unspecific radiolucent lesions in the jaws to establish a firm diagnosis and avoid inappropriate treatment strategies.
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Life expectancy continuously increases but our society faces age-related conditions. Among musculoskeletal diseases, osteoporosis associated with risk of vertebral fracture and degenerative intervertebral disc (IVD) are painful pathologies responsible for tremendous healthcare costs. Hence, reliable diagnostic tools are necessary to plan a treatment or follow up its efficacy. Yet, radiographic and MRI techniques, respectively clinical standards for evaluation of bone strength and IVD degeneration, are unspecific and not objective. Increasingly used in biomedical engineering, CT-based finite element (FE) models constitute the state-of-art for vertebral strength prediction. However, as non-invasive biomechanical evaluation and personalised FE models of the IVD are not available, rigid boundary conditions (BCs) are applied on the FE models to avoid uncertainties of disc degeneration that might bias the predictions. Moreover, considering the impact of low back pain, the biomechanical status of the IVD is needed as a criterion for early disc degeneration. Thus, the first FE study focuses on two rigid BCs applied on the vertebral bodies during compression test of cadaver vertebral bodies, vertebral sections and PMMA embedding. The second FE study highlights the large influence of the intervertebral disc’s compliance on the vertebral strength, damage distribution and its initiation. The third study introduces a new protocol for normalisation of the IVD stiffness in compression, torsion and bending using MRI-based data to account for its morphology. In the last study, a new criterion (Otsu threshold) for disc degeneration based on quantitative MRI data (axial T2 map) is proposed. The results show that vertebral strength and damage distribution computed with rigid BCs are identical. Yet, large discrepancies in strength and damage localisation were observed when the vertebral bodies were loaded via IVDs. The normalisation protocol attenuated the effect of geometry on the IVD stiffnesses without complete suppression. Finally, the Otsu threshold computed in the posterior part of annulus fibrosus was related to the disc biomechanics and meet objectivity and simplicity required for a clinical application. In conclusion, the stiffness normalisation protocol necessary for consistent IVD comparisons and the relation found between degeneration, mechanical response of the IVD and Otsu threshold lead the way for non-invasive evaluation biomechanical status of the IVD. As the FE prediction of vertebral strength is largely influenced by the IVD conditions, this data could also improve the future FE models of osteoporotic vertebra.
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BACKGROUND The activation of multiple pro- and anti-inflammatory mediators is a key feature in the pathophysiology of sepsis. Many of these mediators may directly contribute to organ dysfunction and determine disease severity. So far our ability to modulate these upregulated mediator pathways is very limited. Therefore the adsorption of such mediators via an extracorporeal circuit may be a beneficial intervention during sepsis. OBJECTIVES Recent technical innovations have made this intervention feasible. Both systems for exclusive mediator adsorption and for adsorption beside a conventional renal replacement therapy are now available. Some of the membranes can adsorb a broad range of mediators by rather unspecific binding, whereas others specifically adsorb endotoxin or mediators. DISCUSSION Whilst biochemical efficacy could be demonstrated by some of the systems, controlled and randomized studies demonstrating improved clinical endpoints are still lacking. Therefore the use of such therapies outside clinical studies cannot yet be recommended.
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Impaired eye movements have a long history in schizophrenia research and meet the criteria of a reliable biomarker. However, the effects of cognitive load and task difficulty on saccadic latencies (SL) are less understood. Recent studies showed that SL are strongly task dependent: SL are decreased in tasks with higher cognitive demand, and increased in tasks with lower cognitive demand. The present study investigates SL modulation in patients with schizophrenia and their first-degree relatives. A group of 13 patients suffering from ICD-10 schizophrenia, 10 first-degree relatives, and 24 control subjects performed two different types of visual tasks: a color task and a Landolt ring orientation task. We used video-based oculography to measure SL. We found that patients exhibited a similar unspecific SL pattern in the two different tasks, whereas controls and relatives exhibited 20–26% shorter average latencies in the orientation task (higher cognitive demand) compared to the color task (lower cognitive demand). Also, classification performance using support vector machines suggests that relatives should be assigned to the healthy controls and not to the patient group. Therefore, visual processing of different content does not modulate SL in patients with schizophrenia, but modulates SL in the relatives and healthy controls. The results reflect a specific oculomotor attentional dysfunction in patients with schizophrenia that is a potential state marker, possibly caused by impaired top-down disinhibition of the superior colliculus by frontal/prefrontal areas such as the frontal eye fields.
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BACKGROUND: We evaluated Swiss slaughterhouse data for integration in a national syndromic surveillance system for the early detection of emerging diseases in production animals. We analysed meat inspection data for cattle, pigs and small ruminants slaughtered between 2007 and 2012 (including emergency slaughters of sick/injured animals); investigating patterns in the number of animals slaughtered and condemned; the reasons invoked for whole carcass condemnations; reporting biases and regional effects. RESULTS: Whole carcass condemnation rates were fairly uniform (1-2‰) over time and between the different types of production animals. Condemnation rates were much higher and less uniform following emergency slaughters. The number of condemnations peaked in December for both cattle and pigs, a time when individuals of lower quality are sent to slaughter when hay and food are limited and when certain diseases are more prevalent. Each type of production animal was associated with a different profile of condemnation reasons. The most commonly reported one was "severe lesions" for cattle, "abscesses" for pigs and "pronounced weight loss" for small ruminants. These reasons could constitute valuable syndromic indicators as they are unspecific clinical manifestations of a large range of animal diseases (as well as potential indicators of animal welfare). Differences were detected in the rate of carcass condemnation between cantons and between large and small slaughterhouses. A large percentage (>60% for all three animal categories) of slaughterhouses operating never reported a condemnation between 2007 and 2012, a potential indicator of widespread non-reporting bias in our database. CONCLUSIONS: The current system offers simultaneous coverage of cattle, pigs and small ruminants for the whole of Switzerland; and traceability of each condemnation to its farm of origin. The number of condemnations was significantly linked to the number of slaughters, meaning that the former should be always be offset by the later in analyses. Because this denominator is only communicated at the end of the month, condemnations may currently only be monitored on a monthly basis. Coupled with the lack of timeliness (30-60 days delay between condemnation and notification), this limits the use of the data for early-detection.
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Diagnosis and therapy of male hypogonadism is still a challenge because of the unspecific clinical signs and symptoms. The clinical presentation of a androgen deficiency is age-related. In the adult men, one can often observe fatigue, decrease in physical capacity, loss of libido and erectile dysfunction. At the physical examination, genitalia have always to be assessed in search of a testes/penis atrophy. Two fasting measurements of total testosterone concentrations by a reliable assay are needed to confirm the diagnosis. By assessing gonadotropines the origin of hypogonadism can be determined (central/secondary or peripheral/primary). Exogenous administration of androgens should be considered in young, sportive, healthy and muscular males. Patients with metabolic syndrome should only be screened for hypogonadism in the presence of suggestive symptoms. Prostate disease, hematocrit higher than 50 %, uncontrolled heart failure and severe obstructive sleep apnea are contraindications of a testosterone replacement therapy. Patients with metabolic-syndrome-associated low testosterone levels should firstly benefit from a lifestyle intervention that can normalize clinical and biochemical hypogonadism. So far, there is no clear evidence for a possible benefit of testosterone therapy in patients with the metabolic syndrome. Similarly, in patients with PADAM (partial androgen deficiency of the aging male) testosterone therapy is not established or recommended.
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INTRODUCTION Clinical treatment of spinal metastasis is gaining in complexity while the underlying biology remains unknown. Insufficient biological understanding is due to a lack of suitable experimental animal models. Intercellular adhesion molecule-1 (ICAM1) has been implicated in metastasis formation. Its role in spinal metastasis remains unclear. It was the aim to generate a reliable spinal metastasis model in mice and to investigate metastasis formation under ICAM1 depletion. MATERIAL AND METHODS B16 melanoma cells were infected with a lentivirus containing firefly luciferase (B16-luc). Stable cell clones (B16-luc) were injected retrogradely into the distal aortic arch. Spinal metastasis formation was monitored using in vivo bioluminescence imaging/MRI. Neurological deficits were monitored daily. In vivo selected, metastasized tumor cells were isolated (mB16-luc) and reinjected intraarterially. mB16-luc cells were injected intraarterially in ICAM1 KO mice. Metastasis distribution was analyzed using organ-specific fluorescence analysis. RESULTS Intraarterial injection of B16-luc and metastatic mB16-luc reliably induced spinal metastasis formation with neurological deficits (B16-luc:26.5, mB16-luc:21 days, p<0.05). In vivo selection increased the metastatic aggressiveness and led to a bone specific homing phenotype. Thus, mB16-luc cells demonstrated higher number (B16-luc: 1.2±0.447, mB16-luc:3.2±1.643) and increased total metastasis volume (B16-luc:2.87±2.453 mm3, mB16-luc:11.19±3.898 mm3, p<0.05) in the spine. ICAM1 depletion leads to a significantly reduced number of spinal metastasis (mB16-luc:1.2±0.84) with improved neurological outcome (29 days). General metastatic burden was significantly reduced under ICAM1 depletion (control: 3.47×10(7)±1.66×10(7); ICAM-1-/-: 5.20×10(4)±4.44×10(4), p<0.05 vs. control) CONCLUSION Applying a reliable animal model for spinal metastasis, ICAM1 depletion reduces spinal metastasis formation due to an organ-unspecific reduction of metastasis development.
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Background. Prenatal diagnosis of Optiz G/BBB syndrome (OS) is challenging because the characteristic clinical features, such as facial and genitourinary anomalies, may be subtle at sonography and rather unspecific. Furthermore, molecular testing of the disease gene is not routinely performed, unless a specific diagnosis is suggested. Method. Both familial and ultrasound data were used to achieve the diagnosis of X-linked OS (XLOS), which was confirmed by molecular testing of MID1 gene (Xp22.3) at birth. Results. Sequencing of MID1 gene disclosed the nucleotide change c.1285 +1 G>T, previously associated with XLOS. Conclusions. This case illustrates current challenges of the prenatal diagnostic work-up of XLOS and exemplifies how clinical investigation, including family history, and accurate US foetal investigations can lead to the correct diagnosis.