Ethephon induced oxidative stress in the olive leaf abscission zone enables development of a selective abscission compound.

BACKGROUND: Table olives (Olea europaea L.), despite their widespread production, are still harvested manually. The low efficiency of manual harvesting and the rising costs of labor have reduced the profitability of this crop. A selective abscission treatment, inducing abscission of fruits but not leaves, is crucial for the adoption of mechanical harvesting of table olives. In the present work we studied the anatomical and molecular differences between the three abscission zones (AZs) of olive fruits and leaves. RESULTS: The fruit abscission zone 3 (FAZ3), located between the fruit and the pedicel, was found to be the active AZ in mature fruits and is sensitive to ethephon, whereas FAZ2, between the pedicel and the rachis, is the flower active AZ as well as functioning as the most ethephon induced fruit AZ. We found anatomical differences between the leaf AZ (LAZ) and the two FAZs. Unlike the FAZs, the LAZ is characterized by small cells with less pectin compared to neighboring cells. In an attempt to differentiate between the fruit and leaf AZs, we examined the effect of treating olive-bearing trees with ethephon, an ethylene-releasing compound, with or without antioxidants, on the detachment force (DF) of fruits and leaves 5 days after the treatment. Ethephon treatment enhanced pectinase activity and reduced DF in all the three olive AZs. A transcriptomic analysis of the three olive AZs after ethephon treatment revealed induction of several genes encoding for hormones (ethylene, auxin and ABA), as well as for several cell wall degrading enzymes. However, up-regulation of cellulase genes was found only in the LAZ. Many genes involved in oxidative stress were induced by the ethephon treatment in the LAZ alone. In addition, we found that reactive oxygen species (ROS) mediated abscission in response to ethephon only in leaves. Thus, adding antioxidants such as ascorbic acid or butyric acid to the ethephon inhibited leaf abscission but enhanced fruit abscission. CONCLUSION: Our findings suggest that treating olive-bearing trees with a combination of ethephon and antioxidants reduces the detachment force (DF) of fruit without weakening that of the leaves. Hence, this selective abscission treatment may be used in turn to promote mechanized harvest of olives.

Marker-assisted selection based on a multi-trait economic index in chicken: Experimental results and simulation.

A method proposed herein allows simultaneous selection for several production traits, taking into consideration their marginal economic values (i.e. the economic value of a trait's additional unit). This economic index-marker assisted selection (EI-MAS) method is based on the calculation of the predicted economic breeding value (BV), using information on DNA markers that have previously been found to be associated with relevant quantitative trait loci. Based on the proposed method, results with real birds showed that sire progeny performance was significantly correlated with expected performance (r = 0.61-0.76; P = 0.03-0.01). Simulation analysis using a computer program written specifically for this purpose suggested that the relative advantage of EI-MAS would be large for traits with low heritability values. As expected, the response to EI-MAS was higher when the map distance between the marker and the quantitative trait gene was small, and vice versa. A large number of distantly located markers, spread 10 cM apart, yielded higher response to selection than a small number of closely located markers spread 3 cM apart. Additionally, the response to EI-MAS was higher when a large number (ca.150) of progeny was used for the prediction equation.

Application of SNPs for assessing biodiversity and phylogeny among yeast strains.

We examined the efficacy of single-nucleotide polymorphism (SNP) markers for the assessment of the phylogeny and biodiversity of Saccharomyces strains. Each of 32 Saccharomyces cerevisiae strains was genotyped at 30 SNP loci discovered by sequence alignment of the S. cerevisiae laboratory strain SK1 to the database sequence of strain S288c. In total, 10 SNPs were selected from each of the following three categories: promoter regions, nonsynonymous and synonymous sites (in open reading frames). The strains in this study included 11 haploid laboratory strains used for genetic studies and 21 diploids. Three non-cerevisiae species of Saccharomyces (sensu stricto) were used as an out-group. A Bayesian clustering-algorithm, Structure, effectively identified four different strain groups: laboratory, wine, other diploids and the non-cerevisiae species. Analysing haploid and diploid strains together caused problems for phylogeny reconstruction, but not for the clustering produced by Structure. The ascertainment bias introduced by the SNP discovery method caused difficulty in the phylogenetic analysis; alternative options are proposed. A smaller data set, comprising only the nine most polymorphic loci, was sufficient to obtain most features of the results.

Evidence for a major gene affecting the transition from normoglycaemia to hyperglycaemia in Psammomys obesus.

We investigated the mode of inheritance of nutritionally induced diabetes in the desert gerbil Psammomys obesus (sand rat), following transfer from low-energy (LE) to high-energy (HE) diet which induces hyperglycaemia. Psammomys selected for high or low blood glucose level were used as two parental lines. A first backcross generation (BC(1)) was formed by crossing F(1) males with females of the diabetes-prone line. The resulting 232 BC(1) progeny were assessed for blood glucose. All progeny were weaned at 3 weeks of age (week 0), and their weekly assessment of blood glucose levels proceeded until week 9 after weaning, with all progeny maintained on HE diet. At weeks 1 to 9 post weaning, a clear bimodal distribution statistically different from unimodal distribution of blood glucose was observed, normoglycaemic and hyperglycaemic at a 1:1 ratio. This ratio is expected at the first backcross generation for traits controlled by a single dominant gene. From week 0 (prior to the transfer to HE diet) till week 8, the hyperglycaemic individuals were significantly heavier (4--17%) than the normoglycaemic ones. The bimodal blood glucose distribution in BC(1) generation, with about equal frequencies in each mode, strongly suggests that a single major gene affects the transition from normo- to hyperglycaemia. The wide range of blood glucose values among the hyperglycaemic individuals (180 to 500 mg/dl) indicates that several genes and environmental factors influence the extent of hyperglycaemia. The diabetes-resistant allele appears to be dominant; the estimate for dominance ratio is 0.97.

Management of hemorrhoidal disease in patients with chronic spinal cord injury.

Hemorrhoidal disease is a common pathology in patients with chronic spinal cord injury (SCI). We describe our experience with the primary approach to this problem at the Proctology Division of the Sheba Medical Center. We treated 29 patients (26 men) with paraplegia due to SCI between 1995 and 1999. The mean age was 49 years (range, 22-74 years). All patients had hemorrhoids in stages ranging between II and IV. Main complaints were rectal bleeding (83%), difficulties in evacuation (38%) and discomfort or pain (28%). Eleven patients (38%) were treated conservatively (e. g. diet, hygiene and laxatives), while 18 patients (62%) underwent either banding or sclerotherapy of hemorrhoids or both. No major complication were observed. In 28 of 29 patients (96%), there was a significant reduction or cessation of bleeding and/or relief of symptoms; one patient (3%) required hemorrhoidectomy. Of the 28 successful treatments, 16 (57%) had partial reduction of bleeding or relief of symptoms, while in 12 (43%) response was complete. Of those who were treated conservatively, 9 (82%) had partial and 2 (18%) had complete relief of symptoms. Of those who had banding/sclerotherapy, 7 (41%) had partial and 10 (59%) had complete relief. We also examined the effect of perianal sensation on the treatment outcome. Of 16 patients with complete anesthesia, 11 (69%) had partial and 5 (31%) had complete relief, whereas of the 12 patients with preserved sensation, 5 (42%) had partial and 7 (58%) had complete relief. In conclusion, the approach of banding or sclerotherapy of hemorrhoids in SCI patients is safe and effective. When sensation of the perianal region is preserved, the outcome seems to be better. The cause of SCI has no impact on the treatment results. There was no difference in the outcome of treatment between patients with stage II and stage III hemorrhoids; patients with stage IV hemorrhoids seem to do worse than those with stages II and III.

Telomerase activity in patients with transitional cell carcinoma: a preliminary study.

BACKGROUND: Telomerase activity is not detectable in normal cells, and their telomers shorten until the chromosome is unable to replicate. Immortal cells have short but stable chromosomes and increased telomerase activity. Transitional cell carcinoma (TCC) has only a few useful markers of diagnostic or prognostic importance. The objective of this study was to determine whether there was a correlation between telomerase activity and the grade or stage of TCC, and whether the enzyme's activity could serve as a biochemical marker of this tumor. METHODS: The study included 29 patients with TCC. From each patient, samples of urine cells were obtained, and a cup biopsy was taken from an apparently normal area as well as from a part of the bladder tumor resected transurethrally. Control uroepithelial biopsies were taken from normal transitional cell sites from non-TCC patients. Biopsies or cells were subjected to either histologic examination or telomerase activity determination. RESULTS: Twenty-six of 29 (90%) of the tumor biopsies exhibited telomerase activity. Most of the cup biopsies were categorized as metaplastic or dysplastic, and 20 of 29 (69%) of these exhibited telomerase activity. Telomerase activity was found in 17 of 21 (81%) of the urine cells but in only 3 of 14 (21%) of control urine cells. All (10 of 10) of the uroepithelial biopsies taken from non-TCC patients did not show any telomerase activity. CONCLUSIONS: In this study, almost all tumor biopsies exhibited telomerase activity. The high incidence of telomerase activity found in cup biopsies of the malignant field uroepithelial cells from cup biopsies of TCC patients may suggest that telomerase could be activated early in carcinogenesis. A high incidence of telomerase activity was found in voided uroepithelial cells of TCC patients; however, no correlation between this activity and the histologic determination of grading and staging of the tumor was found.

Elevated plasma atrial natriuretic peptide levels after occlusion of the thoracic aorta.

STUDY OBJECTIVE: The influence of occlusion of the thoracic aorta by an intraluminal balloon on plasma atrial natriuretic peptide (ANP) levels was evaluated in humans. METHODS: The changes in plasma ANP and plasma norepinephrine levels, and hemodynamic parameters were measured in 10 patients under general anesthesia undergoing regional chemotherapy treatment involving the 15-min inflation and subsequent deflation of an intraaortic balloon. RESULTS: The hemodynamic changes observed were similar to those seen during aortic clamping and declamping in patients undergoing vascular surgery. Plasma ANP levels (median+/-SD) measured 1 min after inflation (146+/-117 pg/mL) and 1 min after deflation (168+/-189 pg/mL) of the aortic balloon were significantly higher than baseline values (83+/-55 pg/mL), with a mean increase, respectively, of 92% and 97% (95% confidence intervals [CI], 50 to 147% and 53 to 152%). Plasma ANP levels were still elevated 30 min after deflation (121+/-94 pg/mL), a 56% increase (95% CI, 21 to 100%), although the hemodynamic parameters had already returned to their baseline levels. There was no evidence that the hemodynamic variables were associated with changes in plasma ANP levels (all p values > 0.30). In addition, there was no evidence of an association between plasma ANP and plasma norepinephrine levels at any of the four individual sampling points (p > 0.17). Thirty minutes after deflation, however, norepinephrine levels were higher than baseline values. CONCLUSIONS: The changes in plasma ANP levels after aortic occlusion and reinstitution of blood flow may be dependent on parameters other than atrial stretch and pressure.

Spontaneous leak and transection of permanent subclavian catheters.

BACKGROUND AND OBJECTIVES: Implanted central venous access ports are frequently used. Spontaneous break and catheter transection are serious but rare complications of permanent subclavian catheters. We report our experience with this serious complication and identify possible warning signs. MATERIALS AND METHODS: Between 1990 and 1996, 285 permanent subclavian catheters were placed at the Sheba Medical Center, Tel Hashomer, Israel. RESULTS: We evaluated the patient population for this complication and searched for possible warning signs. A total of 12 patients (4.2%) with this complication were identified, 8 with transection and distal embolization and 4 with a partial tear only. The pinch-off sign was noted as an early warning in only 5 patients. All other patients developed symptoms only immediately before the diagnosis of this complication. The mean duration from insertion to identification of tear or transection was 9.6 months (range 1-24 months). CONCLUSION: Awareness and clinical suspicion are most important in identification and prevention of this serious complication. Catheters should be taken out when treatment is completed or after 12 months in order to prevent catheter breaks.

Sentinel lymph node involvement--a predictor for axillary node status with breast cancer--has the time come?

AIMS: Axillary node dissection for breast cancer is important for staging and its prognostic value. Sentinel nodes are defined as the first nodes into which the primary cancer drains. This study investigates whether identification, removal and pathological examination of these nodes indicates whether the completion of axillary lymphadenectomy is required. METHODS: Using a vital dye injected at the primary tumour site, we were able to identify sentinel nodes in 96 out of 98 women examined. RESULTS: An average number of 2.7 +/- 1.2 nodes per patient were identified as sentinel nodes. In 83% of cases there was a correlation between the involvement of the sentinel nodes and the rest of the axillary nodes. In 14% of patients the sentinel nodes were the only nodes involved with tumour. In three cases the sentinel nodes were negative, but other axillary nodes were tumour-positive. CONCLUSION: The major problem in routine application of this method to the decision to perform axillary lymph node dissection (ALND) is the time needed for pathological identification of lymph node involvement by tumor.

Hemodynamic changes during a new procedure for regional chemotherapy involving occlusion of the thoracic aorta and inferior vena cava.

STUDY OBJECTIVE: To describe the hemodynamic consequences of a regional chemotherapy procedure involving occlusion of the thoracic aorta and inferior vena cava (IVC) by intraluminal balloons. DESIGN: Prospective study. SETTING: Operating rooms of an academic hospital. PATIENTS: 10 patients with inoperable intraabdominal malignancy. INTERVENTIONS: After the induction of general anesthesia and the insertion of a pulmonary artery catheter the patients underwent the regional chemotherapy procedure. MEASUREMENTS AND MAIN RESULTS: Occlusion of the thoracic aorta induced an increase in blood pressure (BP) and systemic vascular resistance (SVR) (41% +/- 8% and 80% +/- 15% from baseline, respectively), and a 30% +/- 7% decrease in cardiac output (CO). After aortic balloon deflation at the end of the procedure, we observed a decrease in BP to baseline values, decrease in SVR (to 62% +/- 12% below baseline), and increase in CO (to 80% +/- 15% above baseline). Those changes resemble those described during vascular surgery. Isolated occlusion of the IVC before aortic occlusion caused hemodynamic deterioration in only three of 10 patients, suggesting incomplete obstruction or collateral blood flow in others. Occluding the IVC while the aorta was occluded, caused minimal hemodynamic changes. CONCLUSIONS: Independent inflation of the IVC balloon should not be performed routinely because of possible unpredicted hemodynamic instability. Inferior vena cava occlusion should always be performed after complete aortic occlusion, because it is then that it produces negligible hemodynamic consequences. It is possible that a better assessment of IVC occlusion after balloon inflation needs to be done by contrast injection to prevent a possible leak of chemotherapeutic drugs.

Isolation limb perfusion with tumor necrosis factor alpha and chemotherapy for advanced extremity soft tissue sarcomas.

The unique property of high dose recombinant tumor necrosis factor alpha (rTNF alpha) is to activate and selectively destroy the tumor-associated microvasculature. For the systemic application of rTNF alpha it has been shown that the maximum tolerated dose (MTD) is 10 times less than the effective dose in animals. The main toxicity corresponds to systemic inflammatory response syndrome with a decrease in vascular resistance and hypotension. We found that it is possible to administer rTNF alpha at 10 times the MTD in an isolated limb perfusion (ILP) system with heart-lung machine, for locally advanced extremity soft tissue sarcomas. One hundred forty patients received an ILP with high-dose TNF alpha. In 55 patients treated with the combination of high-dose rTNF alpha + interferon-gamma + melphalan an overall objective response rate of 87% with 36% complete responses was observed; it was 81% and 28%, respectively, in a group treated with TNF alpha and melphalan (n = 85). Angiographic and immunohistological studies showed the selective and early damage of the sarcoma-associated microvasculature preceded by the upregulation of adhesion molecules and intratumoral leak of von Willebrand factor. Tumor invasion by platelets and, in some cases, by polymorphonuclear cells, appeared within hours after the application of rTNFa long before the lysis of the tumor. Thus, ILP with high-dose TNF alpha and chemotherapy seems to act through a dual targeting: TNF hits the tumor associated vasculature, and chemotherapy attacks the tumor cells. Therefore, ILP with TNF is a new option in the management of locally advanced soft tissue sarcoma of the extremities.

Avoiding diarrhea after subtotal colectomy with primary anastomosis in the treatment of colon cancer.

BACKGROUND: Subtotal colectomy has been criticized as causing increased frequency of stool passage, thus adding to the patients' morbidity. We review our experience with subtotal colectomy and determine the factors affecting postoperative diarrhea. STUDY DESIGN: One hundred thirty-six patients with colon cancer were treated by primary subtotal colectomy. Of these, 30 percent underwent an emergency resection; 15 percent, semi-emergency resection; and 55 percent, elective subtotal colectomy. There were 29 complications and 3 deaths. RESULTS: The incidence of complications was higher when the operation was carried out on an emergency or semi-emergency basis. In assessing the patients' increased postoperative stool frequency, there was no difference between the groups; but, the length of the remaining colon and the resected terminal ileum had a significant effect on postoperative diarrhea. If less than 10 cm of terminal ileum is resected and more than 10 cm of colon is left above the peritoneal reflection, there is a marked decrease in the incidence of diarrhea after subtotal colectomy. CONCLUSIONS: Subtotal colectomy is an acceptable treatment for left colonic carcinoma, electively as well as in emergency situations. Postoperative diarrhea can be minimized by attention to the length of small bowel and sigmoid that are resected.

[Identification of sentinel and axillary node involvement in breast cancer].

Axillary node dissection for breast cancer is important for staging and prognosis. "Sentinel nodes" are the first nodes into which primary cancer drains. Identification, removal and pathological examination of those nodes indicates whether completion of axillary lymphadenectomy is required. The sentinel nodes are identified using a vital dye injected at the primary tumor site. With this technique we were able to identify sentinel nodes in 46 of 48 (95%) women examined. An average of 2.7 +/- 1.2 nodes were identified as sentinel nodes. In 81% of cases there was a correlation between involvement of sentinel nodes and of other axillary nodes as well. In 10% of patients sentinel nodes were involved with tumor while other axillary nodes were negative. The major problem in routine application of this is relationship in surgical decisions is reliable real time pathological identification of lymph node involvement by tumor.

Isolated limb perfusion with tumor necrosis factor and melphalan for limb salvage in 186 patients with locally advanced soft tissue extremity sarcomas. The cumulative multicenter European experience.

OBJECTIVE: The objective of the study was to achieve limb salvage in patients with locally advanced soft tissue sarcomas that can only be treated by amputation or functionally mutilating surgery by performing an isolated limb perfusion (ILP) with tumor necrosis factor (TNF) + melphalan (M) as induction biochemotherapy to obtain local control and make limb-sparing surgery possible. SUMMARY BACKGROUND DATA: To increase the number of limb-sparing resections in the treatment of locally advanced extremity soft tissue sarcoma, preoperative radiation therapy or chemotherapy or a combination of the two often are applied. The ILP with cytostatic agents alone is another option but rarely is used because of rather poor results. The efficacy of the application of TNF in ILP markedly has changed this situation. METHODS: In 8 cancer centers, 186 patients were treated over a period of almost 4.5 years. There were 107 (57%) primary and 79 (43%) recurrent sarcomas, mostly high grade (110 grade III; 51 grade II; and 25 very large, recurrent, or multiple grade I sarcomas). The composition of this series of patients is unusual: 42 patients (23%) had multifocal primary or multiple recurrent tumors; median tumor size was very large (16 cm); 25 patients (13%) had known systemic metastases at the time of the ILP. Patients underwent a 90-minute ILP at 39 to 40 C with TNF + melphalan. The first 55 patients also received interferon-tau. A delayed marginal resection of the tumor remnant was done 2 to 4 months after ILP. RESULTS: A major tumor response was seen in 82% of the patients rendering these large sarcomas resectable in most cases. Clinical response rates were: 33 complete response (CR) (18%), 106 partial response (PR) (57%), 42 no change (NC) (22%), and 5 progressive disease (PD) (3%). Final outcome was defined by clinical and pathologic response: 54 CR (29%), 99 PR (53%), 29 NC (16%), and 4 PD (2%). At a median follow-up of almost 2 years (22 months; range, 6-58 months), limb salvage was achieved in 82%. Regional toxicity was limited and systemic toxicity minimal to moderate, easily managed, with no toxic deaths. CONCLUSIONS: In the setting of isolated limb perfusion, TNF is an active anticancer drug in patients. The ILP with TNF + melphalan can be performed safely in many centers and is an effective induction treatment with a high response rate that can achieve limb salvage in patients with locally advanced extremity soft tissue sarcoma.

Regional hyperthermic perfusion with cisplatin following surgery for malignant melanoma of the extremities.

BACKGROUND: The study was undertaken to review our experience in the treatment of extremity melanoma with hyperthermic isolated limb perfusion (HILP), using cisplatin as the chemotherapeutic agent. We also evaluated the best timing for regional lymph node dissection in relation to the perfusion. PATIENTS AND METHODS: Sixty patients with advanced malignant melanoma of the limbs were treated with HILP used mainly as an adjuvant treatment. There were 56 lower- and 4 upper-limb HILPs. Cisplatin was used at a dose of 20 mg/L of limb volume. Temperature at the tumor site was 39 degrees C to 40 degrees C. Postoperative complications, disease-free period, and time to recurrence were recorded. RESULTS: There were no deaths related to the procedure. Forty-seven percent of the patients developed local complications; most complications were minor and resolved within 60 days. The local complication rate was higher when HILP was performed shortly after or simultaneously with regional lymph node dissection. None of the patients had systemic complications. Mean survival time from treatment was 87.2 months. Currently, 35 patients (58%) are alive and free of disease 52.7 +/- 22.5 months after HILP. Twelve patients (20%) are alive with recurrent disease, of which 5 recurred locally. The average time (+/- standard error of the mean) to recurrence was 24.5 +/- 13.8 months after perfusion. CONCLUSIONS: HILP with cisplatin is a relatively safe procedure, which seems to increase locoregional control of advanced malignant melanoma of the extremity. Separating the timing of lymph node dissection from HILP by 6 to 8 weeks reduces the complication rate.