Severe hypercholesterolemia in a 2-year-old

Routine and selective cholesterol screening of children is an effective tool to help identify those with familial hypercholesterolemia. In children found to have elevated levels of cholesterol, secondary causes should be excluded, including hypothyroidism. Thyroid hormone has multiple effects on the regulation of lipid synthesis, absorption, and metabolism. In this case report, we described a 2-year-old with a history of congenital hypothyroidism who was found to have severe hypercholesterolemia. A detailed medical history and appropriate screening tests are important in determining the underlying cause of elevated low-density lipoprotein cholesterol to help inform clinical decision-making.     

Zebrafish scarb2a insertional mutant reveals a novel function for the Scarb2/Limp2 receptor in notochord development

Background: Scarb2 or Limp2 belong to a subfamily of Scavenger receptors described as lysosomal transmembrane glycosylated receptors, that are mutated in the human syndrome AMRF (action myoclonus‐renal failure). The zebrafish insertional mutant scarb2a^hi1463Tg has notochord defects, the notochord is a defining feature of chordates running along the center of the longitudinal axis and it is essential for forming the spinal column in all vertebrates. Results: There are three paralogous scarb2 genes in zebrafish; scarb2a, scarb2b, and scarb2c. Both Scarb2a and Scarb2b proteins lack the classical di‐leucine motif. We found that scarb2a^hi1463Tg homozygous zebrafish embryos have a null mutation impairing vacuole formation in the notochord and simultaneously disrupting proper formation of the basement membrane resulting in its thickening at the ventral side of the notochord, which may be the cause for the anomalous upward bending observed in the trunk. Through whole‐mount in situ hybridization, we detected scarb2a mRNA expression in the notochord and in the brain early in development. However, it is puzzling that scarb2a notochord mRNA expression is short‐lived in the presumptive notochord and precedes the complete differentiation of the notochord. Conclusions: This work describes a novel function for the Scarb2 receptor as an essential glycoprotein for notochord development. Developmental Dynamics 245:508–519, 2016. © 2015 Wiley Periodicals, Inc.     

AMIGO2 mRNA expression in hippocampal CA2 and CA3a

AMIGO2, or amphoterin-induced gene and ORF (open reading frame) 2, belongs to the leucine-rich repeats and immunoglobulin superfamilies. The protein is a downstream target of calcium-dependent survival signals and, therefore, promotes neuronal survival. Here, we describe the mRNA distribution pattern of AMIGO2 throughout the mouse brain with special emphasis on the hippocampus. In the Ammon’s horn, a detailed comparison between the subregional mRNA expression patterns of AMIGO2 and Pcp4 (Purkinje cell protein 4)—a known molecular marker of hippocampal CA2 (Cornu Ammonis 2)—revealed a prominent AMIGO2 mRNA expression level in both the CA2 and the CA3a (Cornu Ammonis 3a) subregion of the dorsal and ventral hippocampus. Since this CA2/CA3a region is particularly resistant to neuronal injury and neurotoxicity [Stanfield and Cowan (Brain Res 309(2):299–307 1984); Sloviter (J Comp Neurol 280(2):183–196 1989); Leranth and Ribak (Exp Brain Res 85(1):129–136 1991); Young and Dragunow (Exp Neurol 133(2):125–137 1995); Ochiishi et al. (Neurosci 93(3):955–967 1999)], we suggest that the expression pattern of AMIGO2 indeed fits with its involvement in neuroprotection.     

Retroperitoneal dedifferentiated liposarcoma lacking MDM2 amplification in a patient with a germ line CHEK2 mutation

Germ line mutations in genes that encode proteins involved in the DNA damage response predispose patients to a variety of tumors. Checkpoint kinase 2, encoded by the CHEK2 gene, is important in transducing the DNA damage response. Germ line CHEK2 mutations are seen in a subset of patients with a familial breast cancer and sarcoma phenotype. We report a case of retroperitoneal dedifferentiated liposarcoma in a 61-year-old female with germ line CHEK2 mutation. MDM2 gene amplification normally present and used to aid in the diagnosis of retroperitoneal dedifferentiated liposarcoma was absent in this case. Lack of MDM2 overexpression has similarly been reported in liposarcomas arising in patients with germ line TP53 mutations. We propose this case may highlight a nonamplified MDM2 phenotype in well- and dedifferentiated liposarcomas arising in patients with germ line mutations of genes involved in p53-associated DNA damage response pathways.     

The adenosine a2a receptor inhibits matrix-induced inflammation in a novel fashion

Endogenous mediators within the inflammatory milieu play a critical role in directing the scope, duration, and resolution of inflammation. High-molecular-weight extracellular matrix hyaluronan (HA) helps to maintain homeostasis. During inflammation, hyaluronan is broken down into fragments that induce chemokines and cytokines, thereby augmenting the inflammatory response. Tissue-derived adenosine, released during inflammation, inhibits inflammation via the anti-inflammatory A2 adenosine receptor (A2aR). We demonstrate that adenosine modulates HA-induced gene expression via the A2aR. A2aR stimulation inhibits HA fragment-induced pro-fibrotic genes TNF-alpha, keratinocyte chemoattractant (KC), macrophage inflammatory protein (MIP)-2, and MIP-1alpha while simultaneously synergizing with hyaluronan fragments to up-regulate the TH1 cytokine IL-12. Interestingly, A2aR stimulation mediates these affects via the novel cAMP-activated guanine nucleotide exchange factor EPAC. In addition, A2aR-null mice are more susceptible to bleomycin-induced lung injury, consistent with a role for endogenous adenosine in inhibiting the inflammation that may lead to fibrosis. Indeed, the bleomycin treated A2aR-null mice demonstrate increased lung inflammation, HA accumulation, and histologic damage. Overall, our data elucidate the opposing roles of tissue-derived HA fragments and adenosine in regulating noninfectious lung inflammation and support the pursuit of A2aR agonists as a means of pharmacologically inhibiting inflammation that may lead to fibrosis.     

Pregnancy-associated a2-glycoprotein in rheumatoid arthritis.

Pregnancy-associated alpha2-glycoprotein (PAG) was found to be increased in sera and synovial fluids of patients suffering from rheumatoid arthritis tested in the single radial immunodiffusion. The PAG levels in rheumatoid sera correlated well with the activity of arthritis in the patients. The purified PAG inhibited clearly the 3H-thymidine uptake of normal lymphocytes stimulated with phytohemagglutinin and also the spontaneous attachment of sheep erythrocytes to normal lymphocytes. 17 of 19 rheumatoid plasmas inhibited the 3H-thymidine uptake of normal lymphocytes and intensity of their inhibitory effects correlated with serum PAG levels.     

Type 2 Gaucher's disease in a Malian family

Gaucher's disease is a recessive autosomal disorder caused by an inherited deficiency of betaglucocerebrosidase. We report here the case of an 8 month old child, fourth in a family of four children, who presents the neuropathic form of the disease. The dosages of betaglucosidase activity using C (14 ) techniques have confirmed the diagnosis, and allowed the detection of the disease in the elder brother. Both parents were considered as responsible for the transmission of this disease to their progeny. The type 2 Gaucher's disease is rare in black population, and may be associated with phenotypes heterogeneity.     

Glycosylation is a key in SARS-CoV-2 infection

Journal of Molecular Medicine - SARS-CoV-2 causes the respiratory syndrome COVID-19 and is responsible for the current pandemic. The S protein of SARS-CoV-2-mediating virus binding to target cells...