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R DeMatteo

Publications and source records attributed to R DeMatteo.

4 recordsLinked to original sources

Extended hepatic resection: a 6-year retrospective study of risk factors for perioperative mortality.

BACKGROUND: Extended hepatic resection (more than four liver segments) is a major operative procedure that is associated with significant risk. The purpose of this study was to assess the impact of perioperative variables on in-hospital mortality after extended hepatectomy. STUDY DESIGN: Consecutive patients who underwent extended hepatic resection were studied. The prognostic value of 29 perioperative variables was evaluated using in-hospital mortality as the endpoint. For each variable, the odds ratio (95% confidence interval) for in-hospital mortality was calculated. Those variables with a lower confidence limit > 1 were considered important risk factors. The population was stratified into categories of patients having the same number of risk factors, and mortality was estimated for each group. These data were used to develop a risk assessment algorithm. RESULTS: There were 14 deaths (6%) in 226 patients. Three preoperative variables (cholangitis, creatinine > 1.3 mg/dL, and total bilirubin > 6 mg/dL) and two operative variables (blood loss > 3 L and vena caval resection) appear to be important factors for in-hospital mortality. The mortality associated with the presence of any two of the five factors was 100% (5 of 5), and the mortality associated with the absence of these factors was 3% (6 of 191). CONCLUSIONS: Perioperative evaluation of patients undergoing extended hepatic resection should include the quantitation of mortality risk factors. The combination of any two factors among preoperative cholangitis, elevated serum creatinine, elevated serum bilirubin, high operative blood loss, and vena cava resection may carry a high mortality risk. These results require prospective validation.

Adolescent↗

Hand-assisted laparoscopic liver resection: lessons from an initial experience.

BACKGROUND: Recent innovations in laparoscopic instrumentation make routine resection of solid organs a clinical possibility. HYPOTHESIS: Hand-assisted laparoscopic liver resection is a safe and feasible procedure for solitary cancers requiring removal of 2 segments of liver or less. DESIGN AND PATIENTS: Eleven patients with liver tumors deemed technically resectable by laparoscopic techniques were subjected to laparoscopic evaluation and attempted hand-assisted laparoscopic resection between July 1998 and July 1999. During the same period, 230 patients underwent open liver resection. SETTING: Tertiary care referral center for liver cancer. MAIN OUTCOME MEASURES: Success of laparoscopic resection, reasons for conversion to open liver resection, blood loss, tumor clearance margin, complications, and length of hospital stay. RESULTS: Five patients underwent successful resection by the hand-assisted laparoscopic technique. Data from the 5 successful cases and the 6 aborted cases are presented to outline the issues and the lessons learned. CONCLUSIONS: In selected patients, hand-assisted laparoscopic liver resection can be safely performed and might have potential advantages over traditional liver resection if the tumor is limited to the left lateral segment or is at the margins of the liver.

Adult↗

Adenoviral-mediated gene transfer to murine small intestine is more efficient in neonates than adults.

PURPOSE: The authors sought to assess the feasibility of in vivo gene transfer to the small intestine using recombinant adenovirus in neonatal and adult mice. METHODS: H5.010CMVlacZ is a replication-defective, E1-deleted human type 5 adenovirus, which contains the lacZ gene under the control of a cytomegalovirus promoter and enhancer. The lacZ gene was used as a marker because its gene product, beta-galactosidase, is readily detected by X-gal histochemistry. Sixty neonatal (3 to 5 days old) and 45 adult (6 to 8 weeks old) C57BL/6 mice were investigated. Intestinal gene transfer was attempted with H5.010CMVlacZ by intraperitoneal (i.p.), intraluminal (IL), and intramural (i.m.) injection. Based on prior studies, the optimal dose of H5.010CMVlacZ was 1 x 10(8) plaque forming units (pfu/mL). Control animals received saline injections. Gene transfer on repeat administration of adenovirus has been shown to be prevented by neutralizing antibody. To determine if neonatal inoculation induced a humoral immune response, neonates (n = 5) that received i.p. injections were rechallenged with intravenous H5.010CMV alkphos, a similar adenoviral construct containing the alkaline phosphatase marker gene. Serum samples were analyzed by Western blot to detect the presence of adenoviral-specific antibody. RESULTS: Gene transfer to neonatal small intestine was successful by IL gastric (n = 8/10), IL jejunal (n = 9/10) and i.p. (n = 10/10) routes 2 days after injection. Macroscopic staining was present in 90% of standardized 2-cm small bowel segments. Transgene expression was identified in intestinal smooth muscle, serosa, and epithelium. Gene transfer to the adult small intestine was successful by IL jejunal (n = 4/5), i.m. (n = 5/5), and i.p. (n = 1/5) injection of adenoviruslacZ with focal staining (< 5% of 2-cm segments) in epithelium including crypts, muscle, and serosa. Three weeks after i.p. H5.010CMVlacZ in neonates, intravenous injection with H5.010CMValkphos resulted in hepatic transgene expression (n = 4/5) that was indistinguishable from a primary intravenous inoculation; persistent, lacZ expression was not detectable in the liver or intestine (n = 0/5). Western blot analysis detected adenoviral-specific antibodies after adult IM but not after neonatal i.p. injection. Furthermore, 3 weeks after neonatal i.p. injection repeat administration by the i.m. route was successful (n = 4/ 4). CONCLUSION: Gene transfer to neonatal and adult small intestine is feasible using recombinant adenovirus and is more efficient in neonates as indicated by increased surface area of marker gene expression, effectiveness of intraperitoneal delivery, and the ability to readminister recombinant adenovirus.

Adenoviruses, Human↗

Transduction with recombinant adeno-associated virus for gene therapy is limited by leading-strand synthesis.

Adeno-associated virus is an integrating DNA parvovirus with the potential to be an important vehicle for somatic gene therapy. A potential barrier, however, is the low transduction efficiencies of recombinant adeno-associated virus (rAAV) vectors. We show in this report that adenovirus dramatically enhances rAAV transduction in vitro in a way that is dependent on expression of early region 1 and 4 (E1 and E4, respectively) genes and directly proportional to the appearance of double-stranded replicative forms of the rAAV genome. Expression of the open reading frame 6 protein from E4 in the absence of E1 accomplished a similar but attenuated effect. The helper activity of adenovirus E1 and E4 for rAAV gene transfer was similarly demonstrated in vivo by using murine models of liver- and lung-directed gene therapy. Our data indicate that conversion of a single-stranded rAAV genome to a duplex intermediate limits transduction and usefulness for gene therapy.

Adenovirus E1 Proteins↗