Israel Medical Association Journal

Background: The contribution of the abnormal DNA mismatch repair system to non-small cell lung cancer tumorigenesis is controversial and has not been reported in Jewish Israeli patients. Similarly, the involvement of 3p deletions in NSCLC[1] in the same population has not been assessed.

Objectives: To assess the contribution of the DNA-MMR[2] system to NSCLC pathogenesis by analyzing microsatellite instability, and evaluate loss of heterozygosity at 3p rates in Israeli NSCLC patients.

Methods: Paired DNA from tumorous and non-tumorous tissue was extracted, and genotyping for MSI[3] determination was carried out using the five Bethesda markers and for determining LOH[4] two 3p markers were used. Genotyping was performed using polymerase chain reaction amplification and size separation on an ABI semiautomatic DNA sequencer, and the allelic patterns of tumorous and non-tumorous tissue were compared.

Results: Forty-four NSCLCs from 35 smokers and 9 non-smokers were analyzed, with 26 of the 44 (59%) at stage I disease. Using five microsatellite markers (D17S250, D5S346, D2S123, BAT-25, BAT-26) (known as Bethesda markers) for MSI determination, 6 of the 44 tumors (13.6%) exhibited MSI in at least one marker. Similarly, genotyping for LOH at chromosome 3p was performed using two markers (D3S4103, D3S1234) located at 3p14.2 l. With D3S4103, 33 of the 44 patients successfully analyzed were homozygous and therefore non-informative with respect to LOH. Using D3S1234, 33 of 36 patients (91.7%) were heterozygous, and 23 of these individuals' tumors (69.7%) displayed LOH. Unexpectedly, 4 of 33 tumors (12.1%) genotyped by D3S4103, and 16 of 36 tumors (44.5%) genotyped by D3S1234 showed a pattern of MSI, even though only one of these tumors showed a similar pattern when genotyped with the five consensus markers. Overall, 23 of 44 tumors (52.3%) demonstrated MSI on at least one marker, and 5 of these 23 tumors (21.7%) had MSI on two or more markers.

Conclusions: MSI using 3p markers and not the Bethesda markers occurs at a high rate and in early stages in Jewish NSCLC patients.

Human embryonic stem cells may serve as a potentially endeless source of  transplantable cells to treat various neurologic disorders. Accumulating data have shown the therapeutic value of various neural precursor cell types in experimental models of neurologic diseases. Tailoring cell therapy for specific disorders requires the generation of cells that are committed to specific neural lineages. To this end, protocols have been developed recently for the derivation of dopaminergic neurons, spinal motor neurons and oligodendrocytes from hESC[1]. These protocols recapitulate normal development in culture conditions. However, a novel concept emerging from these studies is that the beneficial effect of transplanted stem cells is not only via cell replacement in damaged host tissue, but also by trophic and protective effects, as well as by an immunomodulatory effect that down-regulates detrimental brain inflammation.

Background: Ischemic mitral regurgitation is associated with reduced survival after coronary artery bypass surgery.

Objectives: To compare long-term survival among patients undergoing coronary surgery for reduced left ventricular function and severe ischemic MR[1] in whom the valve was either repaired, replaced, or no intervention was performed.

Methods: Eighty patients with severe left ventricular dysfunction and severe MR underwent coronary bypass surgery. The mean age of the patients was 65 years (range 42–82), and 63 (79%) were male. Sixty-three (79%) were in preoperative NYHA functional class III-IV (mean NYHA 3.3), and 26 (32%) were operated on an urgent/emergent basis. Coronary artery bypass surgery was performed in all patients. The mitral valve was repaired in 38 and replaced in 14, and in 28 there was no intervention. The clinical profile was similar in the three groups, although patients undergoing repair were slightly younger.

Results: Operative mortality was 15% (8%, 14%, and 25% for the repair, replacement and no intervention respectively; not significant). Long-term follow up was 100% complete, for a mean of 38 months (range 2–92). Twenty-nine patients (57%) were in NYHA I-II (mean NYHA 2.3). Among the surgery survivors, late survival was improved in the repair group compared to the other groups (P < 0.05). Predictors for late mortality were non-repair of the mitral valve, residual MR, and stroke (P = 0.005).

Conclusions: Patients with severe ischemic cardiomyopathy and severe MR undergoing coronary bypass surgery should have a mitral procedure at the time of surgery. Mitral valve repair offers a survival advantage as compared to replacement or no intervention on the valve. Patients with residual MR had the worst results.

Stem cell research offers great hope to patients suffering from neuronal damage. Stem cell-based regenerative medicine holds huge potential to provide a true cure for patients affected by a neurodegenerative disease or who have suffered a stroke.

Background: Bladder exstrophy is a severe congenital defect that requires a multidisciplinary treatment approach. Soft tissue repair may be successful during the first few days after birth but a combination of pelvic osteotomies and bladder reconstruction is necessary later in life. The combination of externally fixed anterior and posterior osteotomies has biomechanical advantages over previous techniques for achieving primary bladder closure.

Objectives: To describe our experience with a combined vertical and horizontal pelvic osteotomy approach for the repair of bladder exstrophy.

Methods: Four children underwent bladder exstrophy closure; the mean age at surgery was 19 months (range 9–33 months)... We stabilized the osteotomies with a small Synthes AO external fixator, 4.0 mm rod diameter.

Results: All four patients had successful bladder repair with no dehiscence; two of them achieved partial continence, and bladder neck reconstruction is planned for the other two. Three of the four patients sustained neurologic injury; two completely recovered, and the third continues to suffer from right drop foot. The average follow-up was 39 months (range 10–60 months).

Conclusions: Vertical and horizontal pelvic osteotomies stabilized by external fixator and bladder repair is an effective treatment for bladder exstrophy.

Background: Contralateral exploration of the groin has been common practice among pediatric surgeons for nearly 50 years, based on the high incidence of patent processus vaginalis on the contralateral side with the potential for the subsequent development of a hernia.

Objectives: To evaluate transinguinal laparoscopic examination of the contralateral side during repair of inguinal hernia in children in order to reach a decision regarding exploration of the contralateral side.

Methods: Over a of 21 month period 124 children with unilateral inguinal hernia underwent laparoscopic evaluation of the contralateral groin. The operations were performed under general anesthesia as ambulatory procedures.

Results: Transinguinal contralateral laparoscopic exploration was positive (patent processus vaginalis) in 26 children (21%) and negative (closed processus vaginalis) in 88 (71%). Failure to introduce the telescope occurred in 10 patients (8%) due to a friable or narrow hernia sac. Twenty-five children below 2 years of age were spared exploration of the contralateral side as a result of the negative laparoscopic examination. On the other hand, 15 children aged 2–17 had their contralateral groin explored because of a positive finding at laparoscopy.

Conclusions: Transinguinal laparoscopic examination of the contralateral side during repair of inguinal hernia in children is a simple, safe and quick method to avoid systematic bilateral explorations and should be part of every pediatric surgeon's experience.

Background: Arterial involvement in Behçet's syndrome is rare. Aneurysms are common among the arterial lesions, affecting various arteries but mostly the abdominal aorta. Surgical interposition graft insertion is the treatment of choice for large aneurysms. However, vasculitis in these patients is the reason for the notorious surgical complications that result in up to 50% false aneurysms in anastomotic sites. Recently, endovascular repair for abdominal aortic aneurysms has been established.

Objectives: To learn more about vascular Behçet and, specifically, to compare the results of surgical treatment and endovascular repair of AAA[1] in patients with Behçet's syndrome.

Methods: We retrieved the medical records of all 53 patients with Behçet disease admitted to Rambam Medical Center during the years 1985 and 2001 and analysed the results and follow-up of open surgery versus endovascular repair of AAA in patients with known Behçet's syndrome.

Results: Of the 53 patients with Behçet's disease 18 had vascular manifestations (34%). AAAs were encountered in 8 patients (15%) and 5 were treated. Open surgery (group 1), under general anesthesia, lasted less than 3 hours with an average aortic clamping time of 34 minutes (range 26–41 min) after which the patients were transferred to the intensive care unit for 24–48 hours. Endovascular treatment (group 2), although lasting about the same time without the need for intensive care, necessitated contrast media and fluoroscopy. The length of hospital stay was considerably shorter for patients after endovascular repair compared to open surgery (3 days vs. 6 days). Combined mortality and morbidity was higher in patients who underwent open surgery compared to endovascular repair (one death, one major amputation and three anastomotic pseudoaneurysms compared to one temporary contrast-induced nephropathy).

Conclusions: Vasculo-Behçet patients with AAA are better candidates for endovascular treatment than atherosclerotic patients. Combined morbidity (especially anastomotic pseudoaneurysms) and mortality of Behçet patients after endovascular repair is considerably lower than after open surgery.

Background: About 40% of patients with infective endocarditis will require surgical treatment. The guidelines for such treatment were formulated by the American College of Cardiology and American Heart Association in 1998.

Objectives: To examine our experience with surgical treatment of infective endocarditis in light of these guidelines.

Methods: Surgery was performed in 59 patients with infective endocarditis between 1990 and 1999. The patients' mean age was 48 years (range 13–80). The indications for surgery were hemodynamic instability, uncontrolled infection, and peripheral embolic events. The surgical treatment was based on elimination of infection foci and correction of the hemodynamic derangement. These objectives were met with valve replacement in the majority of patients. Whenever conservative surgery was possible, resection of vegetation and subsequent valve repair were performed and the native valve was preserved.

Results: Six patients (10%) died perioperatively from overwhelming sepsis (n=3), low cardiac output (n=2) and multiorgan failure (n=1). The mean hospital stay was 15.6 days. Of 59 patients, 47 (80%) underwent valve replacement and in 11 (19%) the surgical treatment was based on valve repair. After 1 year of follow up, there was no re-infection.

Conclusion: The new guidelines for surgical treatment of infective endocarditis allow better selection of patients and timing of surgery for this aggressive disease, which consequently decreases the mortality rate. Valve repair is feasible and is preferred whenever possible. According to the new guidelines, patients with neurologic deficit in our series would not have been operated upon, potentially decreasing the operative mortality to 7%.

Fanconi anemia is a rare autosomal recessive disorder characterized clinically by congenital abnormalities, progressive bone marrow failure, and a predisposition to malignancy. FA cells are sensitive to DNA cross-linking agents. Complementation analysis of FA cells using somatic cell fusion has facilitated the identification of eight complementation groups, suggesting that FA is a genetically heterogeneous disorder. Six genes (FANCA, FANCC, FANCD2, FANCE, FANGF, FANCG) have been cloned so far. The majority of affected patients belong to FA group A. Of the 32 unrelated Israeli patients with FA that we studied, 6 carried the FANCC mutations and 15 the FANCA mutations. Among the Jewish patients, ethnic-related mutations were common. Recent cumulative evidence suggests that the FA proteins are repair proteins. FANCC, FANCA and FANCG bind and interact in a protein complex found in the cytoplasm and nucleus of normal cells. FANCD2 exists in two isoforms; the long active form, FANCD2-L, is absent from FA cells of all complementation groups. FANCD2 co-localized with BRCA1 in unclear foci, probably as part of a large genomic surveillance complex. Studies using FANCA and FANCC knockout mice suggest that bone marrow precursors express interferon-g hypersensitivity and show progressive apoptosis. The definition of the molecular basis of FA in many affected families now enables prenatal diagnosis.

Background: Articular cartilage is incapable of undergoing self-repair since chondrocytes lose their mitotic ability as early as the first year of life. Defects in articular cartilage, especially in weight-bearing joints, will predictably deteriorate toward osteoarthritis.  No method has been found to prevent this deterioration. Drilling of the subchondral bone can lead to fibrocartilage formation and temporary repair that slowly degrades. Animal experiments indicate that introducing proliferating chondrocytes such as cultured articular chondrocytes can reliably reconstruct joint defects.

Objectives: To describe our clinical experience in culturing and transplanting autologous chondrocytes. 

Methods: Biopsies were obtained from 10 patients, aged 18–45, undergoing a routine arthroscopy in which a cartilage defect was identified with indications for cartilage transplantation. The biopsies were further processed to establish chondrocyte cultures. ACT was performed in 8 of the 10 patients because of persistent symptoms for at least 2 months post-arthroscopy. All patients (6 men and 2 women) had a grade IV cartilage defect in the medial or lateral femoral condyle, and three had a defect in the trochlear region as well. Biopsies were removed from the lateral rim of the superior aspect of the femur, and cells were cultured in a clean room. Following a 2 order of magnitude expansion, cells were implanted under a periosteal flap.

Results: The eight patients implanted with autologous cells were followed for 6 months to 5 years (average 1 year). Complaints of giving-way, effusion and joint locking resolved in all patients, and pain as assessed by the visual analogue score was reduced by an average of 50%. Follow-up magnetic resonance imaging studies in all patients revealed that the defects were filled with tissue having similar signal characteristics to cartilage.

Conclusions: Chondrocyte implantation is a procedure capable of restoring normal articular cartilage in cases with isolated joint defects. Pain can be predictably reduced, while joint locking and effusion are eliminated. The effect on osteoarthritis progression in humans has not yet been elucidated.

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ACT = autologous chondrocyte transplantation