Analysis of Synaptic Proteins in the Cerebrospinal Fluid as a New Tool in the Study of Inborn Errors of Neurotransmission

Abstract In a few rare diseases, specialised studies in cerebrospinal fluid (CSF) are required to identify the underlying metabolic disorder. We aimed to explore the possibility of detecting key synaptic proteins in the CSF, in particular dopaminergic and gabaergic, as new procedures that could be useful for both pathophysiological and diagnostic purposes in investigation of inherited disorders of neurotransmission. Dopamine receptor type 2 (D2R), dopamine transporter (DAT) and vesicular monoamine transporter type 2 (VMAT2) were analysed in CSF samplesfrom 30 healthy controls (11 days to 17 years) by western blot analysis. Because VMAT2 was the only protein with intracellular localisation, and in order to compare results, GABA vesicular transporter, which is another intracellular protein, was also studied. Spearman’s correlation and Student’s t tests were applied to compare optical density signals between different proteins. All these synaptic proteins could be easily detected and quantified in the CSF. DAT, D2R and GABA VT expression decrease with age, particularly in the first months of life, reflecting the expected intense synaptic activity and neuronal circuitry formation. A statistically significant relationship was found between D2R and DAT expression, reinforcing the previous evidence of DAT regulation by D2R. To our knowledge, there are no previous studies on human CSF reporting a reliable analysis of these proteins. These kinds of studies could help elucidate new causes of disturbed dopaminergic and gabaergic transmission as well as understanding different responses to L-dopa in inherited disorders affecting dopamine metabolism. Moreover, this approach to synaptic activity in vivo can be extended to different groups of proteins and diseases.

Skin Prick Tests and Allergy Diagnosis

Skin testing remains an essential diagnostic tool in modern allergy practice. A signifi cant variability has been reported regarding technical procedures, interpretation of results and documentation. This review has the aim of consolidating methodological recommendations through a critical analysis on past and recent data. This will allow a better understanding on skin prick test (SPT) history; technique; (contra-) indications; interpretation of results; diagnostic pitfalls; adverse reactions; and variability factors.

Restrição do Crescimento Fetal - Casuística de 4 Anos

Overview and aims: Fetal growth restriction (FGR) affects 15% of pregnancies and is associated with both increased perinatal and neonatal morbidity and mortality and long-term effects in adult life. Our aim was to describe cases and outcomes of FGR from a tertiary perinatal care centre and identify the predictors of neonatal morbidity and mortality. Study design: retrospective cohort. Population: pregnancies with early or late FGR caused by placental factors followed from 2006 to 2009 in a tertiary perinatal care centre. Methods: we collected data from clinical records on demographics, clinical history and fetal ultrasound parameters. Perinatal and neonatal outcomes were stratiied according to gestational age (above or below 28 weeks) and we used bivariate analysis to identify any associations with clinical and imaging indings. Results: we included 246 pregnancies; hypertension was the most prevalent maternal risk factor (16%). There were 15 cases of early FGR, 11 of which had cesarean delivery due to deterioration of fetal Doppler parameters. Outcomes in this group included one fetal and three neonatal deaths. Of 231 cases of late FGR, 64% were delivered early given a non-reassuring fetal status i.e. due to changes in Doppler evaluation or altered Manning biophysical proile. There were four cases of perinatal death in this group, three of which delivered at 28 weeks. Neonatal morbidity was associated with lower gestational age, lower birthweight and progressive placental dysfunction (p<0.01). Conclusion: there was an association between neonatal morbidity and gestational age, birthweight and Doppler deterioration, particularly for deliveries below 28 weeks. The assessment of vascular changes through Doppler analysis allows anticipation of fetal deterioration and is a helpful tool in deciding the optimum timing of delivery.

Thoracic Manifestations of Connective Tissue Diseases

Connective tissue diseases (CTDs) comprise several immunologic systemic disorders, each of which associated with a particular set of clinical manifestations and autoimmune profile. CTDs may cause numerous thoracic abnormalities, which vary in frequency and pattern according to the underlying disorder. The CTDs that most commonly involve the respiratory system are progressive systemic sclerosis, systemic lupus erythematosus, rheumatoid arthritis, Sjögren syndrome, polymyositis, dermatomyositis, and mixed connective tissue disease. Pulmonary abnormalities in this group of patients may result from CTD-related lung disease or treatment complications, namely drug toxicity and opportunistic infections. The most important thoracic manifestations of CTDs are interstitial lung disease and pulmonary arterial hypertension, with nonspecific interstitial pneumonia being the most common pattern of interstitial lung disease. High-resolution computed tomography is a valuable tool in the initial evaluation and follow-up of patients with CTDs. As such, general knowledge of the most common high-resolution computed tomographic features of CTD-related lung disease allows the radiologist to contribute to better patient management.

Bone Histomorphometry Revisited

Bone histomorphometry is defined as a quantitative evaluation of bone micro architecture, remodelling and metabolism. Bone metabolic assessment is based on a dynamic process, which provides data on bone matrix formation rate by incorporating a tetracycline compound. In the static evaluation, samples are stained and a semi-automatic technique is applied in order to obtain bone microarchitectural parameters such as trabecular area, perimeter and width. These parameters are in 2D, but they can be extrapolated into 3D, applying a stereological formula. Histomorphometry can be applied to different areas; however, in recent decades it has been a relevant tool in monitoring the effect of drug administration in bone. The main challenge for the future will be the development of noninvasive methods that can give similar information. In the herein review paper we will discuss the general principles and main applications of bone histomorphometry.

Adult B-Cell Acute Lymphoblastic Leukemia Cells Display Decreased PTEN Activity and Constitutive Hyperactivation of PI3K/Akt Pathway Despite High PTEN Protein Levels

Adult B-cell acute lymphoblastic leukemia remains a major therapeutic challenge, requiring a better characterization of the molecular determinants underlying disease progression and resistance to treatment. Here, using a phospho-flow cytometry approach we show that adult diagnostic B-cell acute lymphoblastic leukemia specimens display PI3K/Akt pathway hyperactivation, irrespective of their BCR-ABL status and despite paradoxically high basal expression of PTEN, the major negative regulator of the pathway. Protein kinase CK2 is known to phosphorylate PTEN thereby driving PTEN protein stabilization and concomitant PTEN functional inactivation. In agreement, we found that adult B-cell acute lymphoblastic leukemia samples show significantly higher CK2 kinase activity and lower PTEN lipid phosphatase activity than healthy controls. Moreover, the clinical-grade CK2 inhibitor CX-4945 (Silmitasertib) reversed PTEN levels in leukemia cells to those observed in healthy controls, and promoted leukemia cell death without significantly affecting normal bone marrow cells. Our studies indicate that CK2-mediated PTEN posttranslational inactivation, associated with PI3K/Akt pathway hyperactivation, are a common event in adult B-cell acute lymphoblastic leukemia and suggest that CK2 inhibition may constitute a valid, novel therapeutic tool in this malignancy.