248 research outputs found

    Absolute lymphocyte and neutrophil counts in neonatal ischemic brain injury

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    Objectives: This study aimed to identify differences in absolute neutrophils, lymphocytes, and neutrophil-to-lymphocyte ratio between neonates with two forms of ischemic brain injury, hypoxic-ischemic encephalopathy, and acute ischemic stroke, compared to controls. We also aimed to determine whether this neutrophil/lymphocyte response pattern is associated with disease severity or is a consequence of the effects of total-body cooling, an approved treatment for moderate-to-severe hypoxic-ischemic encephalopathy. Methods: A retrospective chart review of 101 neonates with hypoxic-ischemic encephalopathy+total-body cooling (n=26), hypoxic-ischemic encephalopathy (n=12), acute ischemic stroke (n=15), and transient tachypnea of the newborn (n=48) was conducted; transient tachypnea of the newborn neonates were used as the control group. Absolute neutrophil count and absolute lymphocyte count at three time-intervals (0–12, 12–36, and 36–60 h after birth) were collected, and neutrophilto-lymphocyte ratio was calculated. Results: Hypoxic-ischemic encephalopathy+total-body cooling neonates demonstrated significant time-interval-dependent changes in absolute lymphocyte count and neutrophil-to-lymphocyte ratio levels compared to transient tachypnea of the newborn and acute ischemic stroke patients. Pooled analysis of absolute lymphocyte count for neonates with acute ischemic stroke and hypoxic-ischemic encephalopathy (not hypoxic-ischemic encephalopathy+total-body cooling) revealed that absolute lymphocyte count changes occurring at 0–12h are likely due to disease progression, rather than total-body cooling treatment. Conclusion: These data suggest that the neutrophil/lymphocyte response is modulated following neonatal ischemic brain injury, representing a possible target for therapeutic intervention. However, initial severity of hypoxic-ischemic encephalopathy among these patients could also account for the observed changes in the immune response to injury. Thus, additional work to clarify the contributions of cooling therapy and disease severity to neutrophil/lymphocyte response following hypoxicischemic encephalopathy in neonates is warranted

    Exfoliative cytology and genetic analysis for a non-invasive approach to the diagnosis of white sponge nevus. Case series

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    Background: White Sponge Nevus (WSN) is a rare benign disorder associated with mutations in genes coding for cytokeratin 4 (KRT4) and 13 (KRT13) characterized by dyskeratotic hyperplasia of mucous membranes. This study was aimed at examining different approaches (cytology, pathology and genetic analysis) to WSN diagnosis. Methods: A series of four patients with asymptomatic white diffuse oral lesions were evaluated and, before performing an incisional biopsy for pathology, an oral brush Thin Prep was collected for exfoliative liquid-based cytology (LBC). DNA for genetic analysis was also obtained from patients and both their parents, using buccal swabs. Results: Pathology and cytology showed similar results, leading to the same diagnosis of hyperkeratotic epithelium with acanthosis and spongiosis, without atypia, demonstrating the efficiency of LBC for the differential diagnosis. Sequencing analysis revealed at least 6 rare variants in the KRT4 and KRT13 genes in each patient, contributed in part by both unaffected parents. Conclusions: Thin Prep for oral exfoliative cytology and genetic analysis are sufficient for an accurate diagnosis of WSN. The combination of cytological and genetic analyses could substitute the histologic exam, providing a non-invasive alternative for incisional biopsy

    Mechanisms of the FMR1 Repeat Instability: How Does the CGG Sequence Expand?

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    A dynamic mutation in exon 1 of the FMR1 gene causes Fragile X-related Disorders (FXDs), due to the expansion of an unstable CGG repeat sequence. Based on the CGG sequence size, two types of FMR1 alleles are possible: "premutation" (PM, with 56-200 CGGs) and "full mutation" (FM, with >200 triplets). Premutated females are at risk of transmitting a FM allele that, when methylated, epigenetically silences FMR1 and causes Fragile X syndrome (FXS), a very common form of inherited intellectual disability (ID). Expansions events of the CGG sequence are predominant over contractions and are responsible for meiotic and mitotic instability. The CGG repeat usually includes one or more AGG interspersed triplets that influence allele stability and the risk of transmitting FM to children through maternal meiosis. A unique mechanism responsible for repeat instability has not been identified, but several processes are under investigations using cellular and animal models. The formation of unusual secondary DNA structures at the expanded repeats are likely to occur and contribute to the CGG expansion. This review will focus on the current knowledge about CGG repeat instability addressing the CGG sequence expands

    DNA Methylation, Mechanisms of FMR1 Inactivation and Therapeutic Perspectives for Fragile X Syndrome

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    Among the inherited causes of intellectual disability and autism, Fragile X syndrome (FXS) is the most frequent form, for which there is currently no cure. In most FXS patients, the FMR1 gene is epigenetically inactivated following the expansion over 200 triplets of a CGG repeat (FM: full mutation). FMR1 encodes the Fragile X Mental Retardation Protein (FMRP), which binds several mRNAs, mainly in the brain. When the FM becomes methylated at 10-12 weeks of gestation, the FMR1 gene is transcriptionally silent. The molecular mechanisms involved in the epigenetic silencing are not fully elucidated. Among FXS families, there is a rare occurrence of males carrying a FM, which remains active because it is not methylated, thus ensuring enough FMRPs to allow for an intellectual development within normal range. Which mechanisms are responsible for sparing these individuals from being affected by FXS? In order to answer this critical question, which may have possible implications for FXS therapy, several potential epigenetic mechanisms have been described. Here, we focus on current knowledge about the role of DNA methylation and other epigenetic modifications in FMR1 gene silencing

    Endoscopic Tactile Capsule for Non-Polypoid Colorectal Tumour Detection

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    An endoscopic tactile robotic capsule, embedding miniaturized MEMS force sensors, is presented. The capsule is conceived to provide automatic palpation of non-polypoid colorectal tumours during colonoscopy, since it is characterized by high degree of dysplasia, higher invasiveness and lower detection rates with respect to polyps. A first test was performed employing a silicone phantom that embedded inclusions with variable hardness and curvature. A hardness-based classification was implemented, demonstrating detection robustness to curvature variation. By comparing a set of supervised classification algorithms, a weighted 3-nearest neighbor classifier was selected. A bias force normalization model was introduced in order to make different acquisition sets consistent. Parameters of this model were chosen through a particle swarm optimization method. Additionally, an ex-vivo test was performed to assess the capsule detection performance when magnetically-driven along a colonic tissue. Lumps were identified as voltage peaks with a prominence depending on the total magnetic force applied to the capsule. Accuracy of 94 % in hardness classification was achieved, while a 100 % accuracy is obtained for the lump detection within a tolerance of 5 mm from the central path described by the capsule. In real application scenario, we foresee our device aiding physicians to detect tumorous tissues

    Second-line administration of thrombopoietin receptor agonists in immune thrombocytopenia: Italian Delphi-based consensus recommendations

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    Introduction: In patients with primary immune thrombocytopenia (ITP), a short course of steroids is routinely given as first-line therapy. However, the response is often transient and additional therapy is usually needed. Thrombopoietin receptor agonists (TPO-RAs) are frequently used as second-line therapy, although there is little clinical guidance on the timing of their administration and on tapering/discontinuation of the drug. To provide clinical recommendations, we used the Delphi technique to obtain consensus for statements regarding administration and on tapering/discontinuation of second-line TPO-RAs among a group of Italian clinicians with expertise in management of ITP. Methods: The Delphi process was used to obtain agreement on five statements regarding initiation and on tapering/discontinuation of second-line TPO-RAs. Agreement was considered when 75% of participants approved the statement. Eleven experts participated in the voting. Results: Full consensus was reached for three of the five statements. The experts held that an early switch from corticosteroids to a TPO-RA has the dual advantage of sparing patients from corticosteroid abuse and improve long-term clinical outcomes. All felt that dose reduction of TPO-RAs can be considered in patients with a stable response and platelet count >100 × 109/L that is maintained for at least 6 months in the absence of concomitant treatments, although there was less agreement in patients with a platelet count >50 × 109/L. Near consensus was reached regarding the statement that early treatment with a TPO-RA is associated with an increase in clinically significant partial or complete response. The experts also agreed that optimization of tapering and discontinuation of TPO-RA therapy in selected patients can improve the quality of life. Conclusion: The present consensus can help to provide guidance on use of TPO-RAs in daily practice in patients with ITP. Plain language summary: Second-line administration of thrombopoietin receptor agonists in immune thrombocytopenia There is little guidance on the timing of administration and tapering/discontinuation of thrombopoietin receptor agonists (TPO-RAs) in patients with primary immune thrombocytopenia (ITP).The Delphi technique was used to obtain consensus for five statements.The present consensus among Italian clinicians aims to provide guidance on second-line use of TPO-RAs for patients with ITP in daily practice

    MRX87 family with Aristaless X dup24bp mutation and implication for polyAlanine expansions

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    <p>Abstract</p> <p>Background</p> <p>Cognitive impairments are heterogeneous conditions, and it is estimated that 10% may be caused by a defect of mental function genes on the X chromosome. One of those genes is <it>Aristaless related homeobox </it>(<it>ARX</it>) encoding a polyA-rich homeobox transcription factor essential for cerebral patterning and its mutations cause different neurologic disorders. We reported on the clinical and genetic analysis of an Italian family with X-linked mental retardation (XLMR) and intra-familial heterogeneity, and provided insight into its molecular defect.</p> <p>Methods</p> <p>We carried out on linkage-candidate gene studies in a new MRX family (MRX87). All coding regions and exon-intron boundaries of ARX gene were analysed by direct sequencing.</p> <p>Results</p> <p>MRX87 patients had moderate to profound cognition impairment and a combination of minor congenital anomalies. The disease locus, MRX87, was mapped between DXS7104 and DXS1214, placing it in Xp22-p21 interval, a hot spot region for mental handicap. An in frame duplication of 24 bp (ARXdup24) in the second polyAlanine tract (polyA_II) in ARX was identified.</p> <p>Conclusion</p> <p>Our study underlines the role of ARXdup24 as a critical mutational site causing mental retardation linked to Xp22. Phenotypic heterogeneity of MRX87 patients represents a new observation relevant to the functional consequences of polyAlanine expansions enriching the puzzling complexity of ARXdup24-linked diseases.</p

    Tissue-specific down-regulation of LjAMT1;1 compromises nodule function and enhances nodulation in Lotus japonicus

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    Plant ammonium transporters of the AMT1 family are involved in N-uptake from the soil and ammonium transport, and recycling within the plant. Although AMT1 genes are known to be expressed in nitrogen-fixing nodules of legumes, their precise roles in this specialized organ remain unknown. We have taken a reverse-genetic approach to decipher the physiological role of LjAMT1;1 in Lotus japonicus nodules. LjAMT1;1 is normally expressed in both the infected zone and the vascular tissue of Lotus nodules. Inhibition of LjAMT1;1 gene expression, using an antisense gene construct driven by a leghemoglobin promoter resulted in a substantial reduction of LjAMT1;1 transcript in the infected tissue but not the vascular bundles of transgenic plants. As a result, the nitrogen-fixing activity of nodules was partially impaired and nodule number increased compared to control plants. Expression of LjAMT1;1-GFP fusion protein in plant cells indicated a plasma-membrane location for the LjAMT1;1 protein. Taken together, the results are consistent with a role of LjAMT1;1 in retaining ammonium derived from symbiotic nitrogen fixation in plant cells prior to its assimilation

    ZC4H2, an XLID gene, is required for the generation of a specific subset of CNS interneurons

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    Miles-Carpenter syndrome (MCS) was described in 1991 as an XLID syndrome with fingertip arches and contractures and mapped to proximal Xq. Patients had microcephaly, short stature, mild spasticity, thoracic scoliosis, hyperextendable MCP joints, rocker-bottom feet, hyperextended elbows and knees. A mutation, p.L66H, in ZC4H2, was identified in a XLID resequencing project. Additional screening of linked families and next generation sequencing of XLID families identified three ZC4H2 mutations: p.R18K, p.R213W and p.V75in15aa. The families shared some relevant clinical features. In silico modeling of the mutant proteins indicated all alterations would destabilize the protein. Knockout mutations in zc4h2 were created in zebrafish and homozygous mutant larvae exhibited abnormal swimming, increased twitching, defective eye movement and pectoral fin contractures. Because several of the behavioral defects were consistent with hyperactivity, we examined the underlying neuronal defects and found that sensory neurons and motoneurons appeared normal. However, we observed a striking reduction in GABAergic interneurons. Analysis of cell-type-specificmarkers showed a specific loss of V2 interneurons in the brain and spinal cord, likely arising from mis-specification of neural progenitors. Injected human wt ZC4H2 rescued the mutant phenotype. Mutant zebrafish injectedwith human p.L66H or p.R213W mRNA failed to be rescued, while the p.R18K mRNA was able to rescue the interneuron defect. Our findings clearly support ZC4H2 as a novel XLID gene with a required function in interneuron development. Loss of function of ZC4H2 thus likely results in altered connectivity ofmany brain and spinal circuits
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