Biomedical subjects

Nadav Dujovny

Publications and source records attributed to Nadav Dujovny.

6 recordsLinked to original sources

PubMed2006

Laparoscopic vs. hand-assisted laparoscopic sigmoidectomy for diverticulitis.

INTRODUCTION: Sigmoid colectomy for diverticulitis can be technically challenging because of severe inflammation in the left-lower quadrant and pelvis. We hypothesized that hand-assisted laparoscopic technique may facilitate laparoscopic completion of this surgery while retaining the short-term benefits associated with "pure" laparoscopic surgery, in which an incision is made only for extracting the specimen. This study was designed to compare the outcomes of patients who underwent totally laparoscopic or hand-assisted laparoscopic sigmoidectomy for diverticulitis. METHODS: We reviewed our prospectively collected patient database from July 2001 to June 2004 and compared the intraoperative data and postoperative outcomes of patients who underwent elective laparoscopic or hand-assisted laparoscopic sigmoidectomies for diverticulitis. Complicated patients (with abscess or fistulas) also were separately analyzed. RESULTS: The hand-assisted laparoscopic (mode age, 57 years; 48 percent male) and laparoscopic sigmoidectomy (mode age, 56 years; 90 percent male) groups were similar with regard to age and gender. Overall, patients who underwent laparoscopic (n = 21) vs. hand-assisted laparoscopic (n = 21) sigmoidectomies had a significantly longer operative time (197 +/- 42 vs. 171 +/- 34 minutes, P = 0.04) and shorter incision length (5 +/- 2.1 vs. 9.3 +/- 4.1 cm, P = 0.0001). Patients with complicated diverticulitis (n = 14; abscess, colovesical fistula, enterocolic fistula) who underwent laparoscopic sigmoidectomies (n=4) had a significantly longer operative time compared with hand-assisted laparoscopic sigmoidectomy (n = 10) group (255 +/- 18 vs. 177 +/- 34 minutes, P = 0.001). Conversion rate for the laparoscopic group was significantly higher (3/4 vs. 1/10, P = 0.04, Fisher exact) when complicated diverticulitis was present. There were no differences in postoperative outcomes or incision lengths in the complicated group. CONCLUSIONS: Outcomes after hand-assisted laparoscopic sigmoidectomy for diverticulitis are similar to those seen in the pure laparoscopic method, with lower conversion rates and shorter operative times. Hand-assisted laparoscopic sigmoid resection for diverticulitis is an attractive alternative to a "pure" laparoscopic method in complicated cases.

Adult↗

PubMed2004

Anorectal anatomy and embryology.

The anal canal is complex in its anatomy and its embryologic origin. The intricate and changing histology of the anal canal explains the different types of anal cancer. In addition, an understanding of the venous and the lymphatic drainage of the anal canal helps to explain its methods of dissemination. Finally, the basis for the treatment of anal cancer is derived from the cancer's anatomic origins.

Anal Canal↗

PubMed2003

IFN-gamma production is specifically regulated by IL-10 in mice made tolerant with anti-CD40 ligand antibody and intact active bone.

We have developed a strategy to induce tolerance to allografts, involving cotransplantation of allogeneic intact active bone and transient anti-CD40 ligand mAb therapy. Tolerance induced by this approach in C57BL/6 mice receiving BALB/c hearts is not mediated by deletional mechanisms, but by peripheral regulatory mechanisms. Tolerance is associated with diminished ex vivo IFN-gamma production that is donor specific, and a reduction in the frequency of IFN-gamma-producing cells. Splenocytes from mice tolerant to BALB/c grafts, but sensitized to third-party C3H skin grafts, demonstrated normally primed ex vivo IFN-gamma responses to C3H stimulators. Neutralizing anti-IL-10 and anti-IL-10R, but not anti-TGF-beta, anti-IL-4, or anti-CTLA-4, Abs restored the ex vivo IFN-gamma response to BALB/c stimulators. There was no significant difference in IL-2 or IL-4 production between tolerant and rejecting mice, and anti-IL-10 mAbs had no effect on IL-2 or IL-4 production. The Cincinnati cytokine capture assay was used to test whether suppression of IFN-gamma production in vivo was also a marker of tolerance. In naive mice, we observed a dramatic increase in serum IFN-gamma levels following challenge with allogeneic BALB/c splenocytes or hearts. Tolerant mice challenged with allogeneic BALB/c splenocytes or hearts made significantly less or undetectable amounts of IFN-gamma. No IL-4 or IL-10 production was detected in tolerant or rejecting mice. Collectively, our studies suggest that active suppression of IFN-gamma production by IL-10 is correlated with, and may contribute to, tolerance induced with intact active bone and anti-CD40 ligand mAbs.

Animals↗

PubMed2002

Acute xenograft rejection mediated by antibodies produced independently of TH1/TH2 cytokine profiles.

There is substantial support for the hypothesis that T(H)1 cytokine responses are critical for the normal elaboration of allograft rejection. Recent studies by Wang et al. (1) underscore the importance of T(H)2 responses in xenograft rejection and revealed that T(H)1 cytokines, IL-12 and interferon-gamma (IFN-gamma), can negatively regulate the development of humoral responses necessary for xenograft rejection. Their exceptional studies prompted us to test whether the ability of allografts to elicit cellular rejection and xenografts to induce humoral rejection also result from the differential ability to induce T(H)1 and T(H)2 responses. We compared the kinetics of antibody and cytokine (IFN-gamma and IL-4) production in C57BL/6 mice following allograft transplantation with BALB/c hearts and in C57BL/6 and BALB/c mice following transplantation with Lewis rat hearts. We also compared the ability of BALB/c mice, deficient in the ability to produce IL-4 or IFN-gamma, to reject xenografts and produce xenoantibodies. We observed that T(H)1/T(H)2 cytokine production minimally affected the kinetics of graft rejection but regulated the magnitude of IgG subclass production. Anti-graft IgM played a critical role in initiating acute antibody-mediated xenograft rejection, and the production antigraft IgM was unaffected by IL-4 or IFN-gamma deficiency. In contrast to the report by Wang et al. (1), we conclude that antibody-mediated xenograft rejection in the concordant Lewis rat heart-to-C57BL/6 mouse xenotransplantation model is dependent on anti-IgM production but independent of T(H) cytokine profiles.

Animals↗

PubMedDate not supplied

A pilot study comparing percutaneous decompression with decompressive laparotomy for acute abdominal compartment syndrome in thermal injury.

Abdominal Compartment Syndrome (ACS) has multiple causes, and decompressive laparotomy has been the most frequent modality to prevent worsening cardiovascular, respiratory, and renal function. This pilot study evaluated the utility of percutaneous drainage (PD) of peritoneal fluid compared with decompressive laparotomy in burn patients. A 26-month review was conducted. Nine of 13 (69%) study patients developed intra-abdominal hypertension (IAH) that progressed to abdominal compartment syndrome in 4 (31%). All were treated with PD using a diagnostic peritoneal lavage catheter. Peritoneal fluid analysis revealed a sterile plasma ultrafiltrate with electrolyte and other chemistries reflecting patient serum levels. Five patients underwent PD successfully, and their IAH did not progress to ACS. Four patients with greater than 80% TBSA and severe inhalation injury did not respond to PD and required decompressive laparotomy. There was no evidence of bowel edema, ischemia, or necrosis. All patients requiring decompressive laparotomies died either from sepsis or respiratory failure. Percutaneous decompression is a safe and effective method of decreasing IAH and preventing ACS in patients with less than 80% TBSA thermal injury.

Abdomen↗

PubMedDate not supplied

Effects of a laparoscopic course on student interest in surgical residency.

BACKGROUND: The number of surgical residency applicants has been declining. Early introduction of the discipline of surgery is thought to stimulate early interest in surgical residency. This study investigated the hypothesis that a laparoscopic skills course introduced in preclinical years would stimulate student interest in entering surgical residency. METHODS: Preclinical medical students participated in a laparoscopic skills training course. All students underwent an animate laboratory at the beginning and at the end of the course. Students were divided into 4 separate groups: virtual reality, box trainer, both trainers, and control group. Before and after the course, students were asked their residency interest. First- and second-year medical students participated in the course. RESULTS: Before the course, 56% of the students desired to go into general surgery or a surgical subspecialty. After the course, 49% of the students expressed interest in entering general surgery or a surgical subspecialty. A decrease occurred in students who desired to go into surgical subspecialty residency from 31% to 15% (P = NS), and an increase occurred in students who desired to go into general surgery residency from 25% to 34% (P = NS). No statistically significant difference was seen in the 4 individual training subgroup analyses. CONCLUSIONS: Participation in a laparoscopic skills course does not affect medical student interest in entering surgical residency. A trend was noted in students choosing general surgery over surgical subspecialty training after this course. Surgical educators need to investigate methods to encourage preclinical medical student interest in surgical residencies.

Adult↗