11 research outputs found
Microdeletion del(22)(q12.2) encompassing the facial development-associated gene, MN1 (meningioma 1) in a child with Pierre-Robin sequence (including cleft palate) and neurofibromatosis 2 (NF2): a case report and review of the literature
<p>Abstract</p> <p>Background</p> <p>Pierre-Robin sequence (PRS) is defined by micro- and/or retrognathia, glossoptosis and cleft soft palate, either caused by deformational defect or part of a malformation syndrome. Neurofibromatosis type 2 (NF2) is an autosomal dominant syndrome caused by mutations in the <it>NF2 </it>gene on chromosome 22q12.2. NF2 is characterized by bilateral vestibular schwannomas, spinal cord schwannomas, meningiomas and ependymomas, and juvenile cataracts. To date, NF2 and PRS have not been described together in the same patient.</p> <p>Case presentation</p> <p>We report a female with PRS (micrognathia, cleft palate), microcephaly, ocular hypertelorism, mental retardation and bilateral hearing loss, who at age 15 was also diagnosed with severe NF2 (bilateral cerebellopontine schwannomas and multiple extramedullary/intradural spine tumors). This is the first published report of an individual with both diagnosed PRS and NF2. High resolution karyotype revealed 46, XX, del(22)(q12.1q12.3), FISH confirmed a deletion encompassing <it>NF2</it>, and chromosomal microarray identified a 3,693 kb deletion encompassing multiple genes including <it>NF2 </it>and <it>MN1 </it>(meningioma 1).</p> <p>Five additional patients with craniofacial dysmorphism and deletion in chromosome 22-adjacent-to or containing <it>NF2 </it>were identified in PubMed and the DECIPHER clinical chromosomal database. Their shared chromosomal deletion encompassed <it>MN1</it>, <it>PITPNB </it>and <it>TTC28</it>. <it>MN1</it>, initially cloned from a patient with meningioma, is an oncogene in murine hematopoiesis and participates as a fusion gene (<it>TEL</it>/<it>MN1</it>) in human myeloid leukemias. Interestingly, <it>Mn1</it>-haploinsufficient mice have abnormal skull development and secondary cleft palate. Additionally, <it>Mn1 </it>regulates maturation and function of calvarial osteoblasts and is an upstream regulator of <it>Tbx22</it>, a gene associated with murine and human cleft palate. This suggests that deletion of <it>MN1 </it>in the six patients we describe may be causally linked to their cleft palates and/or craniofacial abnormalities.</p> <p>Conclusions</p> <p>Thus, our report describes a <it>NF2</it>-adjacent chromosome 22q12.2 deletion syndrome and is the first to report association of <it>MN1 </it>deletion with abnormal craniofacial development and/or cleft palate in humans.</p
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
Relativistic X-ray jets from the black hole X-ray binary MAXI J1820+070
The black hole MAXI J1820+070 was discovered during its 2018 outburst and was extensively monitored across the electromagnetic spectrum. Following the detection of relativistic radio jets, we obtained four Chandra X-ray observations taken between 2018 November and 2019 June, along with radio observations conducted with the Very Large Array and MeerKAT arrays. We report the discovery of X-ray sources associated with the radio jets moving at relativistic velocities with a possible deceleration at late times. The broadband spectra of the jets are consistent with synchrotron radiation from particles accelerated up to very high energies (>10 TeV) by shocks produced by the jets interacting with the interstellar medium. The minimal internal energy estimated from the X-ray observations for the jets is ~10^41 erg, significantly larger than the energy calculated from the radio flare alone, suggesting most of the energy is possibly not radiated at small scales but released through late-time interactions
16p13.3 duplication associated with non-syndromic pierre robin sequence with incomplete penetrance.
BACKGROUND: Pierre Robin sequence (PRS) is a condition present at birth. It is characterized by micrognathia, cleft palate, upper airway obstruction, and feeding problems. Multiple etiologies including genetic defects have been documented in patients with syndromic, non-syndromic, and isolated PRS.
CASE PRESENTATION: We report a 4-year-old boy with a complex small supernumerary marker chromosome (sSMC) who had non-syndromic Pierre Robin sequence (PRS). The complex marker chromosome, der(14)t(14;16)(q11.2;p13.13), was initially identified by routine chromosomal analysis and subsequently characterized by array-comparative genomic hybridization (array CGH) and confirmed by fluorescence in situ hybridization (FISH). Clinical manifestations included micrognathia, U-type cleft palate, bilateral congenital ptosis, upslanted and small eyes, bilateral inguinal hernias, umbilical hernia, bilateral clubfoot, and short fingers and toes. To our best knowledge, this was the first case diagnosed with non-syndromic PRS associated with a complex sSMC, which involved a 3.8 Mb gain in the 14q11.2 region and an 11.8 Mb gain in the 16p13.13-pter region.
CONCLUSIONS: We suggest that the duplicated chromosome segment 16p13.3 possibly may be responsible for the phenotypes of our case and also may be a candidate locus of non-syndromic PRS. The duplicated CREBBP gene within chromosome 16p13.3 is associated with incomplete penetrance regarding the mandible development anomalies. Further studies of similar cases are needed to support our findings
South-polar features on Venus similar to those near the north pole.
Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole. The polar dipole is a 'double-eye' feature at the centre of a vast vortex that rotates around the pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a dipole feature existed at the south pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the north pole, but rotating somewhat faster than the northern dipole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south pole are compatible with a sulphuric acid composition
South-polar features on Venus similar to those near the north pole.
Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole. The polar dipole is a 'double-eye' feature at the centre of a vast vortex that rotates around the pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a dipole feature existed at the south pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the north pole, but rotating somewhat faster than the northern dipole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south pole are compatible with a sulphuric acid composition