Developmental and/or epileptic encephalopathies (DEEs) are a group of devastating genetic disorders, resulting in early-onset, therapy-resistant seizures and developmental delay. Here we report on 22 individuals from 15 families presenting with a severe form of intractable epilepsy, severe developmental delay, progressive microcephaly, visual disturbance and similar minor dysmorphisms. Whole exome sequencing identified a recurrent, homozygous variant (chr2:64083454A > G) in the essential UDP-glucose pyrophosphorylase (UGP2) gene in all probands. This rare variant results in a tolerable Met12Val missense change of the longer UGP2 protein isoform but causes a disruption of the start codon of the shorter isoform, which is predominant in brain. We show that the absence of the shorter isoform leads to a reduction of functional UGP2 enzyme in neural stem cells, leading to altered glycogen metabolism, upregulated unfolded protein response and premature neuronal differentiation, as modeled during pluripotent stem cell differentiation in vitro. In contrast, the complete lack of all UGP2 isoforms leads to differentiation defects in multiple lineages in human cells. Reduced expression of Ugp2a/Ugp2b in vivo in zebrafish mimics visual disturbance and mutant animals show a behavioral phenotype. Our study identifies a recurrent start codon mutation in UGP2 as a cause of a novel autosomal recessive DEE syndrome. Importantly, it also shows that isoform-specific start-loss mutations causing expression loss of a tissue-relevant isoform of an essential protein can cause a genetic disease, even when an organism-wide protein absence is incompatible with life. We provide additional examples where a similar disease mechanism applies.
Aggressive fibromatosis is a benign but locally-aggressive tumor, which most often affects the muscles of the shoulder, the pelvic girdle, and the thigh. It usually affects adolescents and young adults. Desmoplastic fibroma, considered the bone counterpart of soft tissue fibromatosis, is a rare tumor that usually affects the metaphyseal or diaphyseal portions of long bones or, less commonly, the jaw. Neuromuscular hamartoma, a rare developmental lesion composed of mature elements of both striated muscle and nerve, is usually diagnosed in infants and children and affects large nerve trunks. Rarely, it can affect the head and neck region. Occasional cases showing an association between aggressive fibromatosis and neuromuscular hamartoma have been reported in the literature. Here we present a unique case of an adult patient with desmoplastic fibroma of the mandible in association with neuromuscular hamartoma.
Inserting Double-j ureteral stent is one of the most popular procedures in urology field. There are different indications for indwelling the stent. For some reasons, it could be neglected for a long time despite its importance. We present a case of 52-year-old patient who had a missed fragment of stent in the urinary bladder for two years with stone formation on one end. We successfully removed the stent and the stone. Such a case is considered rare to deal with during urology practice.
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