Structural modeling of protein-RNA complexes using crosslinking of segmentally isotope-labeled RNA and MS/MS.

Ribonucleoproteins (RNPs) are key regulators of cellular function. We established an efficient approach, crosslinking of segmentally isotope-labeled RNA and tandem mass spectrometry (CLIR-MS/MS), to localize protein-RNA interactions simultaneously at amino acid and nucleotide resolution. The approach was tested on polypyrimidine tract binding protein 1 and U1 small nuclear RNP. Our method provides distance restraints to support integrative atomic-scale structural modeling and to gain mechanistic insights into RNP-regulated processes.

[Is hysterectomy required during vaginal reconstructive pelvic surgery? About histopathological results]. / Faut-il conserver l'utérus lors de la cure de prolapsus ? Réflexions à partir des résultats anatomo-pathologiques.

OBJECTIVES: To evaluate the rate of pre-cancerous and cancerous endometrial lesions in hysterectomy during vaginal reconstructive pelvic surgery. PATIENTS AND METHODS: In this retrospective and continuous study, a vaginal procedure including reconstructive pelvic surgery with vaginal mesh, hysterectomy and adnexectomy was performed in 152 patients between April 2001 and January 2006. An ultrasonography evaluation was done before surgery. A histopathological analysis of uterus, ovaries and tubes was also performed. RESULTS: In the analysis of 136 cases, precancerous and cancerous lesions have been diagnosed while ultrasonography or cervical smear were normal: 2 (1.4%) endocervical dysplasia, 1 (0.7%) cervical epidermoid carcinoma, 10 (7.35%) endometrial complex non-atypical hyperplasia, 7 (5.1%) endometrial atypical hyperplasia and 2 (1.4%) endometrioid endometrial carcinoma. There was not any cancerous lesions in tubes or ovaries. At 10months, mesh exposure was low at 2.9% (four cases). DISCUSSION AND CONCLUSION: The important rate of cancerous and precancerous lesions raise the question of hysterectomy or hysteroscopy and endometrial biopsy in case of uterine preservation during a vaginal reconstructive pelvic surgery.

[Role of ultrasound in the evaluation of patients after laparoscopic sacropexy: preliminary study]. / Intérêt de l'échographie dans le suivi des patientes après promontofixation par coelioscopie: étude préliminaire.

OBJECTIVES: To evaluate results of laparoscopic sacropexy with introital and vaginal ultrasonography, that is to observe dynamic behavior of the mesh, to measure precisely its position and to conclude on the feasibility of this exam. PATIENTS AND METHODS: The surgery was a laparoscopic subtotal hysterectomy and a suspension of the cervix with an anterior vesicovaginal mesh and a posterior rectovaginal mesh. These meshes are joined together and fixed on the sacrum. Ultrasound was performed in fifteen patients to see in the sagital plane the position of the mesh. The distance anterior mesh-bladder neck and the distance posterior mesh-anal sphincter were measured at rest, during straining and during retaining. The spreading out and the dynamic behavior of the mesh were studied. RESULTS: The distance anterior mesh-bladder neck is 12 mm at rest, 15 mm during straining and 13 mm during retaining. The distance posterior mesh-anal sphincter is 30 mm at rest, 26 mm during straining and 31 mm during retaining. The mesh is always seen as spread out, or folded, but never strained. Video recording shows that sacropexy does not block pelvic dynamics. DISCUSSION AND CONCLUSION: Ultrasound imaging appears in this study as a simple and efficient exam to study and measure prosthesis. It could be a good help for clinical examination to explain failure or complication of surgery.