Jacov Tal (1940 – 2005): remembrances of a friend

An obituary commemorates the life and works of Jacov Tal

Network of the Day: Aggregating and Visualizing Entity Networks from Online Sources

This software demonstration paper presents a project on the interactive visualization of social media data. The data presentation fuses German Twitter data and a social relation network extracted from German online news. Such fusion allows for comparative analysis of the two types of media. Our system will additionally enable users to explore relationships between named entities, and to investigate events as they develop over time. Cooperative tagging of relationships is enabled through the active involvement of users. The system is available online for a broad user audience

PrrC-anticodon nuclease: functional organization of a prototypical bacterial restriction RNase

The tRNA(Lys) anticodon nuclease PrrC is associated in latent form with the type Ic DNA restriction endonuclease EcoprrI and activated by a phage T4-encoded inhibitor of EcoprrI. The activation also requires the hydrolysis of GTP and presence of dTTP and is inhibited by ATP. The N-proximal NTPase domain of PrrC has been implicated in relaying the activating signal to a C-proximal anticodon nuclease site by interacting with the requisite nucleotide cofactors [Amitsur et al. (2003) Mol. Microbiol., 50, 129–143]. Means described here to bypass PrrC's self-limiting translation and thermal instability allowed purifying an active mutant form of the protein, demonstrating its oligomeric structure and confirming its anticipated interactions with the nucleotide cofactors of the activation reaction. Mutagenesis and chemical rescue data shown implicate the C-proximal Arg(320), Glu(324) and, possibly, His(356) in anticodon nuclease catalysis. This triad exists in all the known PrrC homologs but only some of them feature residues needed for tRNA(Lys) recognition by the Escherichia coli prototype. The differential conservation and consistent genetic linkage of the PrrC proteins with EcoprrI homologs portray them as a family of restriction RNases of diverse substrate specificities that are mobilized when an associated DNA restriction nuclease is compromised

Parallel dimerization of a PrrC-anticodon nuclease region implicated in tRNALys recognition

The optional Escherichia coli restriction tRNase PrrC represents a family of potential antiviral devices widespread among bacteria. PrrC comprises a functional C-domain of unknown structure and regulatory ABC/ATPase-like N-domain. The possible involvement of a C-domain sequence in tRNALys recognition was investigated using a matching end-protected 11-meric peptide. This mimic, termed here LARP (Lys-anticodon recognizing peptide) UV-cross-linked tRNALys anticodon stem-loop (ASL) analogs and inhibited their PrrC-catalyzed cleavage. Trimming LARP or introducing in it inactivating PrrC missense mutations impaired these activities. LARP appeared to mimic its matching protein sequence in ability to dimerize in parallel, as inferred from the following results. First, tethering Cys to the amino- or carboxy-end of LARP dramatically enhanced the ASL-cross-linking and PrrC-inhibiting activities under suitable redox conditions. Second, Cys-substitutions in a C-domain region containing the sequence corresponding to LARP elicited specific intersubunit cross-links. The parallel dimerization of PrrC's C-domains and expected head-to-tail dimerization of its N-domains further suggest that the NTPase and tRNALys-binding sites of PrrC arise during distinct assembly stages of its dimer of dimers form

Deep Infiltrating Colorectal Endometriosis Treated With Robotic-Assisted Rectosigmoidectomy

Background and Objective: Deep infiltrating pelvic endometriosis with bowel involvement is one of the most aggressive forms of endometriosis. Nowadays, robotic technology and telemanipulation systems represent the latest developments in minimally invasive surgery. the aim of this study is to present our preliminary results and evaluate the feasibility of robotic-assisted laparoscopic colorectal resection for severe endometriosis.Methods: Between September 2009 and December 2011, 10 women with colorectal endometriosis underwent surgery with the da Vinci robotic surgical system (Intuitive Surgical, Sunnyvale, CA, USA). We evaluated the following parameters: short-term complications, clinical outcomes and long-term follow-up, pain relief recurrence rate, and fertility outcomes.Results: Extensive ureterolysis was required in 8 women (80%). Ovarian cystectomy with removal of the cystic wall was performed in 7 women (70%). Torus resection was performed in all women, with unilateral and bilateral uterosacral ligament resection in 1 woman (10%) and 8 women (80%), respectively. in addition to segmental colorectal resection in all cases, partial vaginal resection was necessary in 2 women (20%). An appendectomy was performed in 2 patients (20%). the mean operative time with the robot was 157 minutes (range, 90-190 minutes). the mean hospital stay was 3 days. Six patients had infertility before surgery, with a mean infertility time of 2 years. After a 12-month follow-up period, 4 women (67%) conceived naturally and 2 (33%) underwent in vitro fertilization.Conclusion: We show that robotic-assisted laparoscopic surgery for the treatment of deep infiltrating bowel endometriosis is feasible, effective, and safe.Univ São Paulo, Hosp Clin, Fac Med, São Paulo, BrazilCtr Endometriose São Paulo, São Paulo, BrazilAlbert Einstein Hosp, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilDigimagem Med Diagnost, Radiol Brazilian Coll, São Paulo, BrazilUniv Cent Florida, Dept Obstet & Gynecol, Orlando, FL 32816 USAFlorida Hosp Celebrat Hlth, Celebration, FL USAUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc

Deep Infiltrating Colorectal Endometriosis Treated With Robotic-Assisted Rectosigmoidectomy

Background and Objective: Deep infiltrating pelvic endometriosis with bowel involvement is one of the most aggressive forms of endometriosis. Nowadays, robotic technology and telemanipulation systems represent the latest developments in minimally invasive surgery. The aim of this study is to present our preliminary results and evaluate the feasibility of robotic-assisted laparoscopic colorectal resection for severe endometriosis. Methods: Between September 2009 and December 2011, 10 women with colorectal endometriosis underwent surgery with the da Vinci robotic surgical system (Intuitive Surgical, Sunnyvale, CA, USA). We evaluated the following parameters: short-term complications, clinical outcomes and long-term follow-up, pain relief recurrence rate, and fertility outcomes. Results: Extensive ureterolysis was required in 8 women (80%). Ovarian cystectomy with removal of the cystic wall was performed in 7 women (70%). Torus resection was performed in all women, with unilateral and bilateral uterosacral ligament resection in 1 woman (10%) and 8 women (80%), respectively. In addition to segmental colorectal resection in all cases, partial vaginal resection was necessary in 2 women (20%). An appendectomy was performed in 2 patients (20%). The mean operative time with the robot was 157 minutes (range, 90-190 minutes). The mean hospital stay was 3 days. Six patients had infertility before surgery, with a mean infertility time of 2 years. After a 12-month follow-up period, 4 women (67%) conceived naturally and 2 (33%) underwent in vitro fertilization. Conclusion: We show that robotic-assisted laparoscopic surgery for the treatment of deep infiltrating bowel endometriosis is feasible, effective, and safe