Pheochromocytoma of the urinary bladder: a case report

Urinary bladder pheochromocytoma is rare. From a case report of unsuspected pheochromocytoma and literature review, the authors develop a diagnostic and therapeutic algorithm for the management of this ectopic pheochromocytoma localization

Recognition of exonic splicing enhancer sequences by the Drosophila splicing repressor RSF1

International audienceThe Drosophila repressor splicing factor 1 (RSF1) comprises an N-terminal RNA-binding region and a C-terminal domain rich in glycine, arginine and serine residues, termed the GRS domain. Recently, RSF1 has been shown to antagonize splicing factors of the serine/arginine-rich (SR) family and it is, therefore, expected to play a role in processing of a subset of Drosophila pre-mRNAs through specific interactions with RNA. To investigate the RNA-binding specificity of RSF1, we isolated RSF1-binding RNAs using an in vitro selection approach. We have identified two RNA target motifs recognized by RSF1, designated A (CAACGAC-GA)-and B (AAACGCGCG)-type sequences. We show here that the A-type cognate sequence behaves as an SR protein-dependent exonic splicing enhancer. Namely, three copies of the A-type ligand bind SR proteins, stimulate the efficiency of splicing of reporter pre-mRNAs several fold and lead to inclusion of a short internal exon both in vitro and in vivo. However, three copies of a B-type ligand were much less active. The finding that RSF1 acts as a potent repressor of pre-mRNA splicing in vitro led us to propose that the equilibrium between a limited number of structurally-related general splicing activators or repressors, competing for common or promiscuous binding sites, may be a major determinant of the underlying mechanisms controlling many alternative pre-mRNA processing events

Spectacularly Successful Microsurgical Penile Replantation in an Assaulted Patient: One Case Report

Penile amputation is a rare condition for which immediate surgical replantation is warranted. We present herein one case of a 27-year-old male who presented to the Emergency Department after his wife cut his penis. The penis was replanted microsurgically. The deep dorsal penile veins and superficial veins were anastomosed. Although we could not reanastomose the arteries, wound healing occurred without any problem one week postoperatively and the patient regained erectile function 4 weeks after surgery. At 1-year follow-up examinations he reported on restored erectile function and a normal urinary function

Renal hilar pheochromocytoma: a case report

Paraganglioma is a rare tumor arising from undifferentiated cells of the primitive neural crest. These tumors are most commonly found in the adrenal gland, other localisations are also possible. A 58-year-old woman who presented with history of left lumbar pain, headache, hypertension, palpitation and sweating was found to have a secreting left renal hilar pheochromocytoma. Radical excision of the tumor was therefore undertaken and her hypertension was controlled. From the case report and literature review, the authors suggest a diagnostic and therapeutic strategy for the management of ectopic localization of pheochromocytoma

Conservative Management of a Congenital Seminal Vesicle Cyst Associated with Ipsilateral Renal Agenesis Revealed by Cystitis: One Case Report

Seminal vesicle cyst is an extremely rare disease. Its association with ipsilateral renal agenesis is even more exceptional. We present herein one case of a 16-year-old male who presented with a four-month history of lower urinary tract symptoms (LUTSs) and micturition pain. The digital rectal examination revealed a small mass arising from the prostate. The urine culture showed that E. coli is sensitive to all antibiotics tested. Transrectal ultrasound (TRUS) revealed a cystic mass in the outer prostate. Seminal vesicle cyst and left renal agenesis were confirmed by magnetic resonance imaging (MRI). Maximum flow (Qmax) at uroflow was greater than 15 mL/sec. We therefore decided to manage this disease conservatively with alpha blockers and antibiotics. After 6-month' followup the patient did not report any complain and the uroflow test was similar to a normal urination. From one case report and literature review, the authors suggest a diagnostic and therapeutic strategy for the management of this rare condition

Incontinence urinaire révélant une fistule vésico-utérine: à propos d’un cas

La fistule vésico-utérine (FVU) est une lésion rare et ne représente que 4% de toutes les fistules uro-génitales. Elle est le plus souvent consécutive à une césarienne et réalise une communication entre la vessie et l'utérus. Nous rapportons un cas d'une jeune patiente qui présentait une FVU suite à une césarienne. Le but de ce travail était d'analyser les aspects cliniques et thérapeutiques de cette affection

The RasGAP-associated endoribonuclease G3BP assembles stress granules

Stress granules (SGs) are formed in the cytoplasm in response to various toxic agents, and are believed to play a critical role in the regulation of mRNA metabolism during stress. In SGs, mRNAs are stored in an abortive translation initiation complex that can be routed to either translation initiation or degradation. Here, we show that G3BP, a phosphorylation-dependent endoribonuclease that interacts with RasGAP, is recruited to SGs in cells exposed to arsenite. G3BP may thus determine the fate of mRNAs during cellular stress. Remarkably, SG assembly can be either dominantly induced by G3BP overexpression, or on the contrary, inhibited by expressing a central domain of G3BP. This region binds RasGAP and contains serine 149, whose dephosphorylation is induced by arsenite treatment. Critically, a phosphomimetic mutant (S149E) fails to oligomerize and to assemble SGs, whereas a nonphosphorylatable G3BP mutant (S149A) does both. These results suggest that G3BP is an effector of SG assembly, and that Ras signaling contributes to this process by regulating G3BP dephosphorylation

Protection against Retrovirus Pathogenesis by SR Protein Inhibitors

Indole derivatives compounds (IDC) are a new class of splicing inhibitors that have a selective action on exonic splicing enhancers (ESE)-dependent activity of individual serine-arginine-rich (SR) proteins. Some of these molecules have been shown to compromise assembly of HIV infectious particles in cell cultures by interfering with the activity of the SR protein SF2/ASF and by subsequently suppressing production of splicing-dependent retroviral accessory proteins. For all replication-competent retroviruses, a limiting requirement for infection and pathogenesis is the expression of the envelope glycoprotein which strictly depends on the host splicing machinery. Here, we have evaluated the efficiency of IDC on an animal model of retroviral pathogenesis using a fully replication-competent retrovirus. In this model, all newborn mice infected with a fully replicative murine leukemia virus (MLV) develop erythroleukemia within 6 to 8 weeks of age. We tested several IDC for their ability to interfere ex vivo with MLV splicing and virus spreading as well as for their protective effect in vivo. We show here that two of these IDC, IDC13 and IDC78, selectively altered splicing-dependent production of the retroviral envelope gene, thus inhibiting early viral replication in vivo, sufficiently to protect mice from MLV-induced pathogenesis. The apparent specificity and clinical safety observed here for both IDC13 and IDC78 strongly support further assessment of inhibitors of SR protein splicing factors as a new class of antiretroviral therapeutic agents

The C-terminal domain but not the tyrosine 723 of human DNA topoisomerase I active site contributes to kinase activity

International audienceHuman DNA topoisomerase I not only has DNA relaxing activity, but also splicing factors phosphorylating activity. Topo I shows strong preference for ATP as the phosphate donor. We used photoaffinity labeling with the ATP analogue [α-32 P] 8-azidoadenosine-5′-triphos-phate combined with limited proteolysis to characterize Topo I domains involved in ATP binding. The majority of incorporated analogue was associated with two fragments derived from N-terminal and C-terminal regions of Topo I, respectively. However, mutational analysis showed that deletion of the first 138 N-terminal residues, known to be dispensable for topoisomerase activity, did not change the binding of ATP or the kinase activity. In contrast, deletion of 162 residues from the C-terminal domain was deleterious for ATP binding, kinase and topoisomerase activities. Furthermore, a C-terminal tyrosine 723 mutant lacking topoisomerase activity is still able to bind ATP and to phosphorylate SF2/ASF, suggesting that the two functions of Topo I can be separated. These findings argue in favor of the fact that Topo I is a complex enzyme with a number of potential intra-cellular functions