Minimally invasive surgery for esophageal cancer

Background: Esophageal cancer is among the most deadly cancers worldwide, and esophagectomy remains the standard of care in trying to cure this. Efforts to decrease the incidence of complications in esophagectomy without compromising the efficacy of the procedure have stimulated interest in minimally invasive esophagectomy (MIE), and a wide variety of MIE techniques have been refined by surgeons at specialized centers worldwide. Data sources: Systematic PubMed searches identified articles related to MIE technique, complications, and outcomes. Conclusions: Several techniques have been developed for MIE, none of which has been deemed superior, but as a whole, they represent a safe alternative to open surgery. Available results from case series and comparative studies suggest trends towards improved short‐term outcomes with equivalent efficacy but without definitive advantages.     

A short-term chick embryo in vivo xenograft model to study retinoblastoma cancer stem cells

Purpose:Cancer stem cells (CSCs) reported in various tumors play a crucial role in tumorigenesis and metastasis of retinoblastoma (Rb). Following the efforts to reduce, replace, and refine the use of mammalian models, we aimed to establish a short-term xenograft for Rb to evaluate the CSC properties of CD133^- Rb Y79 cells, using the well-established chick embryo chorioallantoic membrane (CE-CAM) assay.Methods:Y79 cells were cultured, labeled with two different dyes (CM-Dil Y79 and enhanced green fluorescent protein (eGFP)) and sorted for CD133^- and CD133 + subsets. Two million cells from each of the labeled groups were transplanted onto the abraded CAM on embryonic day 7 (E7). On E14, the tumor nodule formation on CAM and spontaneous metastasis to the embryos were evaluated by confocal microscopy, in vivo imaging, and histology.Results:Y79 cells formed pink–white raised perivascular nodules with feeder vessels on the CAM with both the types of labeled CD133^- cells. CD133^- cells, when compared to CD133 + cells, demonstrated significantly larger tumor volume (40.45 ± 7.744 mm³ vs 3.478 ± 0.69 mm³, P = 0.0014) and higher fluorescence intensity (CM-Dil: AUF = 6.37 × 10⁷ ± 7.7 × 10⁶ vs 1.08 × 10⁷ ± 1.6 × 10⁶; P < 0.0001; eGFP: AUF = 13.94 × 10⁴ ± 2.54 × 10⁴ vs AUF = 1.39 × 10⁴ ± 0.4 × 10⁴; P = 0.0003). The metastatic potential of CD133^- cells was also observed to be higher as noted by in vivo imaging and histopathology.Conclusion:This study highlights that CE-CAM is a feasible alternative nonmammalian model for evaluating tumorigenicity and metastatic potential of Y79 CSCs. Increased tumorigenicity and metastatic potential of CD133^- subset of tumor cells substantiate their CSC properties.     

Patient satisfaction with the management of infertility

The objective of this study was to assess patient satisfaction with the investigation and initial management of infertility. A postal questionnaire survey was carried out of 1366 women attending outpatient clinics for the investigation and initial management of infertility at 12 hospitals throughout Scotland. The response rate to the questionnaire was 59% (806/1366). Overall, 87% of responders were satisfied or very satisfied with their care but a number of deficiencies were identified. Thirty-nine per cent had never been asked to bring their partner to the clinic and 86% felt they had not been given enough help with the emotional aspects of infertility. Forty- seven per cent felt they were not given a clear plan for the future and 23% of those who had been given drug treatments reported receiving little or no information about the treatment or possible side-effects. Overall, only a third had been given any written information and 78% expressed a wish for more written information. Women ranked 'the information and explanation given' and the 'attitude of the doctor at the clinic' highly in comparison to other aspects of their care, including 'help with the emotional aspects of infertility'. In general women were satisfied with their care but improvements may be made by giving more explanation and written information and by adopting a more couple-centred approach. Where resources allow, clinics should take steps to address the emotional aspects of infertility.      

DNA adducts, mutant frequencies and mutation spectra in lambda lacZ transgenic mice treated with N-nitrosodimethylamine

Groups of lambda lacZ transgenic mice were treated i.p. with N- nitrosodimethylamine (NDMA) as single doses of 5 mg/kg or 10 mg/kg or as 10 daily doses of 1 mg/kg and changes in DNA N7- or O6-methylguanine or the repair enzyme O6-alkylguanine-DNA alkyltransferase (AGT) were followed for up to 14 days in various tissues. Adduct induction in the liver exceeded by at least one order of magnitude than observed in the next nearest target tissue (lung), and was approximately linearly related to dose, except for O6-methylguanine after the first dose of 1 mg/kg which was lower than expected. Substantial induction of lambda lacZ mutagenesis was observed only in the liver, where the mutant frequency was already maximal within 7 days after 5 mg/kg NDMA and remained unchanged thereafter up to 49 days. Small but marginally significant increases in mutant frequency were consistently observed in the spleen after all three modes of treatment. A lack of proportionality between mutation induction and the administered dose or the corresponding adduct levels was observed, probably reflecting the importance of toxicity-related cell proliferation caused by NDMA at higher doses. Twenty eight days after a dose of 10 mg/kg (causing a 3.6- fold increase in mutant frequency), NDMA was found to increase the frequency of GC-->AT mutations (with a concomitant shift of their preferential location from CpG sites to GpG sites), which made up approximately 60% of the induced mutations. Surprisingly, NDMA also caused a significant increase in deletions of a few (up to 11) base- pairs (22%).      

Thrombospondin promotes platelet aggregation

Thrombospondin (TSP), isolated from human platelets, promotes aggregation of both nonstimulated platelets and platelets stimulated with thrombin or ADP. The TSP-promoted aggregation is specific since a monoclonal antibody against TSP inhibits the effect of exogenously added TSP and inhibits thrombin-induced platelet aggregation in the absence of added TSP. Several lines of evidence suggest that TSP mediates its effect on aggregation of nonstimulated and stimulated platelets through different platelet-surface receptor systems. The TSP- promoted aggregation of nonstimulated platelets was inhibited by a monoclonal antibody to platelet glycoprotein IV (GPIV), but not by a monoclonal antibody to the fibrinogen receptor, GPIIb-IIIa. In contrast, the antibody to GPIIb-IIIa totally inhibited the TSP- potentiated aggregation of thrombin-stimulated platelets, whereas the antibody to GPIV has no effect. Thus, these studies suggest that TSP promotes platelet aggregation by at least two mechanisms--one dependent on and one independent of the platelet fibrinogen receptor system.     

Posttransplant T-cell lymphoproliferative disorders--an aggressive, late complication of solid-organ transplantation

T-cell non-Hodgkin's lymphomas are an uncommon occurrence after solid- organ transplantation. We describe a morphologically and immunophenotypically distinct group of T-cell lymphoproliferative disorders that occurred late in the course of six patients with solid- organ transplants. The patients ranged in age from 31 to 56 years (median, 43). Three were male; all were splenectomized. The interval from transplant to the diagnosis of lymphoma ranged from 4 to 26 years (median, 15). Symptoms at presentation were related to sites of involvement. Pulmonary, marrow, and CNS involvement were present in five, four, and one case, respectively. No patient had lymphadenopathy. Five patients had an elevated lactate dehydrogenase level (range, 226 to 4,880 IU/L; median, 1,220 IU/L). Five of six patients had a leukoerythroblastic reaction. All cases had large-cell histology and frequently contained cytoplasmic granules. Those cases tested expressed CD2, CD3, and CD8 and were negative for B-cell antigens. T-cell receptor beta- and gamma-chain genes were clonally rearranged in three of three and one of three cases, respectively. All T-cell posttransplant lymphoproliferative disorders (T-PTLDs) studied were negative for Epstein-Barr virus (EBV), human T-cell leukemia/lymphoma virus type 1 (HTLV-1), human T-cell leukemia/lymphoma virus type 2 (HTLV-2), and human herpes virus type 8 (HHV-8) genomes. Treatment with acyclovir (three patients) or chemotherapy (three patients) resulted in two responses. All patients had an aggressive course, with a median survival duration of 5 weeks. In conclusion, a clinically aggressive T- PTLD may be a late complication of solid-organ transplantation and does not appear to be related to EBV, HTLV-1, HTLV-2, or HHV-8 infection.     

Urinary nitrite excretion in premature infants: effects of transfusion or indomethacin

Urinary nitrite excretion, an index of L-arginine-dependent nitric oxide formation, was quantified daily for two weeks, in very low-birth-weight (< 1500 g) premature infants. A transient 52%) reduction in nitrite excretion was noted on the day of transfusions (54±10 versus 26±6 μmol/mmol creatinine, before and during transfusion, respectively, n = 24, p<0.02 ). Indomethacin administration in six infants was associated with a dramatic increase in nitrite excretion from a basal median value of 3 to 76 μmol/mmol creatinine (p<0.05). Nitrite excretion returned to baseline on day 3 after indomethacin administration. In two infants who received indomethacin and transfusions on the same day, the stimulatory effect on nitrite excretion by indomethacin overwhelmed any depressive effect of transfusions. These results suggest that L-arginine utilization is influenced by common therapeutic strategies in these high-risk infants.