Robotic transperitoneal infrarenal aortic lymphadenectomy: technique and results.

INTRODUCTION: This study was designed to evaluate the feasibility and the results of robotic transperitoneal infrarenal aortic lymphadenectomy. METHODS: Development of a technique of robotic transperitoneal infrarenal aortic lymphadenectomy in female cadavers and review of the results in 33 patients who underwent the newly developed technique as part of the surgical treatment of gynecologic malignancies. RESULTS: The mean console time was 42 minutes (range, 19-64 minutes). The mean number of nodes was 12.9 (range, 2-27); the mean number of positive nodes was 2.6 (range, 0-8). There was 1 conversion to laparotomy. CONCLUSIONS: Robotic transperitoneal infrarenal aortic lymphadenectomy can be performed adequately and safely with the robotic column at the patient's head. Operating table rotation and additional trocar sites are needed when used in conjunction with robotic pelvic surgery.

Robotic extraperitoneal aortic lymphadenectomy: Development of a technique.

OBJECTIVES: To develop a robotic technique for extraperitoneal aortic lymphadenectomy in cadavers followed by application in a patient with advanced cervical cancer. METHODS: Two fresh frozen female torso cadavers were used to develop the correct placement of the robotic column and trocars, respectively, to allow for a safe and adequate performance of aortic lymphadenectomy using the da Vinci S system. The resulting technique was applied to a patient with cervical cancer Stage IB2 presenting with enlarged aortic nodes. RESULTS: Appropriate sites for trocar and robotic column placement were identified in the female cadavers. In the patient, the operating, docking, and console times were 103, 3.5, and 49 minutes, respectively. The blood loss was 30 ml. Selective removal of 5 enlarged aortic nodes revealed no evidence of metastases. CONCLUSION: Robotic extraperitoneal aortic lymphadenectomy is feasible provided there is proper robotic trocar and column placement. The operating time and number of aortic nodes selectively removed by robotics in this patient are within the range of those reported with an extraperitoneal systematic aortic lymphadenectomy by laparoscopy.

Robotic radical hysterectomy: comparison with laparoscopy and laparotomy.

OBJECTIVE: Comparison of perioperative results of patients undergoing radical hysterectomy by robotics, laparoscopy, and laparotomy. STUDY DESIGN: Prospective analysis of 27 patients undergoing robotic radical hysterectomy between April 2003 and September 2006. Comparison was made with patients operated by laparoscopy and laparotomy matched by age, BMI, site and type of malignancy, FIGO staging, and type of radical hysterectomy. RESULTS: The mean operating times for patients undergoing robotic, laparoscopy and laparotomy radical hysterectomy were 189.6, 220.4, and 166.8 min, respectively; the mean blood loss was 133.1, 208.4, and 443.6 ml, respectively; the mean rate of blood loss was 0.7, 0.9, and 2.6 ml/min, respectively; the mean number of removed lymph nodes was 25.9, 25.9, and 27.7, respectively; and the mean length of hospital stay was 1.7, 2.4, and 3.6 days, respectively. There were no significant differences in intra- or postoperative complications among the three groups, no fistula formation in any patient and no conversions in the robotic or laparoscopic groups. At a mean follow up of 31.1 months, none of the patients with cervical cancer has experienced recurrence. CONCLUSION: Laparoscopy and robotics are preferable to laparotomy for patients requiring radical hysterectomy. Operating times for robotics and laparotomy were similar, and significantly shorter as compared to laparoscopy. Blood loss, rate of blood loss and length of hospital stay were similar for laparoscopy and robotics and significantly reduced as compared to laparotomy.

Genotype frequencies of polymorphic GSTM1, GSTT1, and cytochrome P450 CYP1A1 in Mexicans.

The genotype frequencies of three metabolic polymorphisms were determined in a sample of a typical community in central Mexico. CYP1A1*3, GSTM1, and GSTT1 polymorphisms were studied in 150 donors born in Mexico and with Mexican ascendants; with respect to ethnicity the subjects can be considered Mestizos. PCR reactions were used to amplify specific fragments of the selected genes from genomic DNA. An unexpected 56.7% frequency of the CYP1A1*3 allele (which depends on the presence of a Val residue in the 462 position of the enzyme, instead of Ile) was found, the highest described for open populations of different ethnic origins (i.e., Caucasian, Asian, African, or African American). The GSTM1 null genotype was found with a frequency of 42.6%, which is not different from other ethnicities, whereas the GSTT1 null genotype had a frequency of 9.3%, one of the lowest described for any ethnic group but comparable to the frequency found in India (9.7%). The frequency of the combined genotype CYP1A1*3/*3 and the GSTM1 null allele is one of the highest observed to date (or perhaps the highest): 13.7% among all the ethnicities studied, including Caucasians and Asians, whereas the combination of CYP1A1*3/*3 with the GSTT1 null allele reached only 2.8%. The GSTM1 null allele combined with the GSTT1 null allele, on the other hand, has one of the lowest frequencies described, 4.24%, comparable to the frequencies found in African Americans and Indians. Finally, the combined CYP1A1*3/*3, GSTM1 null allele, and GSTT1 null allele genotype could not be found in the sample studied; it is assumed that the frequency of carriers of these combined genotypes is less than 1%. CYP1A1*3 and CYP1A1*2 polymorphisms were also evaluated in 50 residents in a community of northern Mexico; the CYP1A1*3 frequency was 54%, similar to that found in the other community studied, and the CYP1A1*2 frequency was 40%, which is high compared to Caucasians and Asians but comparable to the frequency found in Japanese and lower than the frequency found in Mapuche Indians. Haplotype frequencies for these CYP1A1 polymorphisms were estimated, and a linkage disequilibrium value (D) of 0.137 was calculated.

Induction of CYP1A1 and CYP2E1 in rat liver by histamine: binding and kinetic studies.

Histamine (HA) may bind to cytochrome P450 (CYP450) in rat liver microsomes. The CYP450-HA complex seems to regulate some cellular processes such as proliferation. In the present work, it is shown that HA increases the activity and protein level of CYP1A1 and CYP2E1, in vivo. CYP1A1 is associated with polycyclic aromatic hydrocarbon-mediated carcinogenesis and CYP2E1 with liver damage by oxidative stress. Studies of enzyme kinetics and binding with rat liver microsomes and supersomes were carried out to determine whether HA is a substrate of CYP1A1 and/or CYP2E1. The lack of NADPH oxidation in the presence of HA showed that it is not a substrate for CYP1A1. Activity measurements using the O-dealkylation of ethoxyresorufin indicated that HA is a mixed-type inhibitor of CYP1A1 in both microsomes and supersomes. On the other hand, HA induced a significant NADPH oxidation catalyzed by CYP2E1 supersomes, strongly suggesting that HA is a substrate for this isoform. Furthermore, HA is consumed in the presence of CYP2E1-induced microsomes and supersomes, as determined by o-phtalaldehyde complexes with HA by HPLC. The present findings may contribute to understand better the physiological function of CYP450 in relation with inflammation and other physiological processes in which HA may have a relevant role.

Increased cytogenetic damage in a zone in transition from agricultural to industrial use: Comprehensive analysis of the micronucleus test in peripheral blood lymphocytes.

A complex situation of chemical exposure has been described in México in a zone that is in transition from rural activities towards intensive industrialization, which has brought environmental pollution: chloroform, methylene chloride, indigo and toluene are some of the pollutants found in the Atoyac and Xochiac rivers. A biomonitoring study was planned in order to establish whether there was a biological effect due to the environmental situation. Communities where leukaemia and thrombocytopenic purpura cases have been reported were included in the study, as well as other communities where such cases have not been described. Three occupations were distinguished, according to chemical exposure: industrial workers, agricultural workers and workers in households, education and commerce. A comprehensive analysis in the micronucleus (MN) test was used to study genotoxicity biomarkers. Two metabolic polymorphisms were determined, namely, glutathione transferase mu1 (GSTM1) and theta1 (GSTT1), which are relevant when oxidative responses are involved. Increased genotoxic damage was found, including cells with >1 MN, >1 chromatin bud, and nucleoplasmic bridges. The genotoxic damage was differentially distributed in the regions studied, being more affected those that are closer to the Atoyac and Xochiac rivers, indicating an effect due to environmental exposure to the contaminants present in the rivers. Further characterization of the exposure regimes in these communities will be done in order to contribute to the alleviation of the health risks that environmental pollution is posing on the inhabitants of this area.

SFTG international collaborative study on in vitro micronucleus test II. Using human lymphocytes.

This study on the in vitro micronucleus assay, comprising 11 laboratories using human lymphocytes, was coordinated by an organizing committee supported by the SFTG (the French branch of the European Environmental Mutagen Society). Nine coded substances were assessed for their ability to induce micronuclei in human lymphocytes in vitro, mitomycin C being used as a positive control. Cultures were exposed to the test substances for a short (early or late) time or for a long time, followed by a short or long recovery period, in the presence of cytochalasin B. Each chemical was evaluated, generally in two laboratories, using three treatment schedules at least twice. The data were assessed for acceptability, and then classified as negative, positive or equivocal. Two of seven genotoxic compounds, namely colchicine and bleomycin, clearly induced micronuclei. Reproducible results were difficult to obtain for some substances, which tended to be those acting at specific stages of the cell cycle. Cytosine arabinoside, diethylstilboestrol and 5-fluorouracil were classified as equivocal. Urethane and thiabendazole were classified as negative. The two presumed non-genotoxic compounds, mannitol and clofibrate, did not induce micronuclei. Repeat testing, exposing cells at both an early and late time after mitogenic stimulation, was needed to detect substances classified as equivocal. These results show the importance of achieving sufficient inhibition of nuclear division to avoid the possibility of missing an effect. The evaluation of micronuclei in mononucleated as well as binucleated cells was particularly useful to detect aneugens. There were no false positive results using lymphocytes, indicating a high specificity. It is concluded that the clastogenic or aneugenic potential in vitro of the substances tested was correctly identified in this study, but that refining the protocol to take into account factors such as the stages of the cell cycle exposed to the compound, or the duration of recovery would be likely to improve the sensitivity of detection using lymphocytes.

Metabolic polymorphisms and the micronucleus frequency in buccal epithelium of adolescents living in an urban environment.

Micronuclei and other biomarkers were evaluated in oral cells from 11- to 16-year-old girls living in a foster home in the central area of México City. Variables analyzed for possible association with these biomarkers include smoking habits, body mass index, metabolic polymorphisms for NAT1 and GSTM1 and whether the cells were obtained from the cheek or pharynx. The results indicated that individuals having the NAT1*10 homozygous genotype showed a significant increase in chromatin buds and binucleated cells. When the damage in the cheek was compared with damage in the pharynx, a significant increase in micronuclei and binucleated cells was found for the latter tissue in all the individuals analyzed.

Infection of rats with Taenia taeniformis metacestodes increases hepatic CYP450, induces the activity of CYP1A1, CYP2B1 and COH isoforms and increases the genotoxicity of the procarcinogens benzo[a]pyrene, cyclophosphamide and aflatoxin B(1).

Infection of rat liver by Taenia taeniformis metacestodes produced an increase in total CYP450 content and induced activity of the CYP1A1, CYP2B1 and COH isoforms. Variations in activity and p450 total content were found with increasing time of infection. During increased activity of p450 isoforms, rats were challenged with carcinogens metabolized by the mentioned isozymes and an increased amount of genotoxic damage was found when benzo[a] pyrene, cyclophosphamide and aflatoxin B(1) were used. No change was seen in CYP2E1 activity. These results support previous findings regarding an increased susceptibility to genotoxic damage of infected organisms.