Neuraxial block for delivery among women with low platelet counts: a retrospective analysis.

BACKGROUND: Laboring women with low platelet counts may be denied neuraxial block due to concerns about causing a spinal-epidural hematoma. AIMS: To assess the anesthetic management, complications and outcome variables of women with low platelet counts, and to expand the existing data regarding the safety of neuraxial blocks in this patient population. METHODS: This is a retrospective analysis of anesthetic and obstetric data from women with platelet counts <100 000/µL, who were admitted to a single referral center during 2011-2014. The rate of neuraxial block and related complications were examined in relation to the platelet count and the results combined with published data to assess the risk of spinal-epidural hematoma. RESULTS: During the study period, 471 of 45 462 women (1%) had a low platelet count (<100 000/µL). The rate of neuraxial block was significantly higher in women with platelet counts of 70-99 000/µL (280/394, 71.1%) when compared to women with platelet counts of 50-69 000/µL and 0 to 49 000/µL (23/59, 38.9% and 5/18, 27.8%, respectively, P <0.0001). Women in the lower platelet count ranges had a higher risk of cesarean delivery under general anesthesia and longer hospital stay. No neuraxial hematoma were reported. CONCLUSIONS: This study contributes a substantial series of neuraxial blocks among women with low platelet counts. The findings support that the risk of hematoma is low if the platelet count is <100 000/µL, specifically between 70 and 99 000/µL. Risk assessment in the lower count ranges requires a much larger sample.

Situación de mepraia spinolai: vector silvestre de la enfermedad de Chagas en Chile en relación con otros vectores desde la perspectiva de sus fuentes de alimentación / Situation of mepraia spinolai: wild vector of Chagas' disease in Chile compared with other vectors from the perspective of their alimentary profile

Background: Three triatomine species, Triatoma infestans, Mepraia spinolai and Mepraia gajardoi, are vectors for Chagas disease in Chile. Aim: To compare the alimentary profile of Mepraia spinolai, the Chilean wild vector of Chagas disease, with that of the several other triatomines. Material and methods: The alimentary profile of Mepraia spinolai was compared with that of other triatomines using cluster analysis (Q and R techniques) with the Jaccard index. Results: Three basic groups of triatomines were identified: domestic, wild and specialists, such as P. coreodes and C. pilosa. Our wild vector M. spinolai was in an intermediate position between wild and domestic clusters, grouping with T. rubrovaria, T. sordida and P. megistus. The feeding sources, animals of the domestic and peri-domestic habitat and wild animals, corresponded to the clusters of the two groups. Conclusions: Mepraia spinolai, being a preponderantly wild species, approaches human dwellings and obtains food from domestic animals and eventually, from human blood

The role of alternative splicing of the adhesion molecule, CD44, in lymphoid malignancy.

AIM: To investigate the expression of CD44 isoforms containing variant exon 6 (v6) in a well characterised cohort of patients with non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukaemia (CLL), and to correlate this with phenotype and disease course. METHODS: Cryostat sections of OCT embedded diagnostic nodal material from NHL patients and cryopreserved mononuclear preparations from CLL patients were used as sources of RNA. After reverse transcription, PCR was carried out with amplimers positioned at either side of the variant exon insertion site to amplify all possible CD44 isoforms. Those isoforms containing v6 were identified after Southern blotting and hybridisation with a radiolabelled oligonucleotide. RESULTS: Of 32 NHL samples analysed, 16 did not express CD44 isoforms containing v6, six expressed an isoform containing exon v6 alone, and 10 expressed v6 long isoforms which contained exon v6 in addition to other variant exons. These data did not correlate with lymphoma classification, disease staging, or the presence or absence of extranodal disease. However, those patients expressing v6 long CD44 isoforms had a worse overall survival than those that did not. The plateau of the survival curves was 50% compared with 82%. No v6 long isoforms were detected in the 21 CLL samples investigated. CONCLUSIONS: The expression of v6 long CD44 isoforms is associated with aggressive disease in NHL, independent of grade, stage, or presence of extranodal disease.

Phase I/II trial of autologous activated macrophages in advanced colorectal cancer.

Autologous activated macrophage (AAM) therapy is an adoptive cellular therapy based on ex vivo differentiation and activation of autologous peripheral blood monocytes. This study was undertaken to evaluate the tolerance, efficiency and biological effects of AAMs in chemoresistant progressive colorectal cancers. From January 1993 to May 1995, 15 patients were treated. Mononuclear cells were collected six times by weekly apheresis, cultured for 7 days, and activated with interferon-gamma. AAMs were then separated by elutriation and re-infused intravenously, with a mean total of 7.95 x 10(9) macrophages per patient. Clinical tolerance was good: toxicity consisted only of a World Health Organisation grade 2 fever after 28% of the infusions. Responses were not seen in the 14 evaluable patients, as expected with very bulky tumours: in 11, the tumours continued to progress, but disease was stabilised in 3 patients who experienced progression-free survival for 14, 12 and 12 weeks, respectively.

Method for quantifying expression of functionally active topoisomerase II in patients with leukaemia.

AIMS: To produce a method to measure and quantify enzymatically active topoisomerase II in normal and neoplastic human cells. METHODS: A crude cell lysate from density separated mononuclear cells from either peripherial blood or bone marrow was prepared as a source of topoisomerases. Using the lysate, minicircles from the Crithedia kinetoplast DNA complex were decatenated before being separated by agarose gel electrophoresis and visualised using ethidium bromide/ultraviolet fluorescence. RESULTS: Cell number, sample volume and drug inhibition concentration required to produce reliable and reproducible assay conditions were established. Intra- and interassay standards were included which permitted the quantification of active topoisomerase II in matched peripheral blood, bone marrow, presentation, and relapse samples from patients with acute lymphoblastic leukaemia. Active topoisomerase II has been converted to a unit scale which has been used to compare topoisomerase II activities in cells from patients with normal blood and bone marrow samples. CONCLUSIONS: There was no change in topoisomerase II activities between samples taken at presentation and those taken during a recurrence. However, topoisomerase II activity in leukaemic blast populations was increased compared with topoisomerase II activity in normal cells.

Infección tripano-triatomina de triatoma spinolai en una zona de riesgo epidemiológico / Tripano-triatomine infection of triatoma spinolai in a zone with epidemiological risk

Triatoma spinolai is the only wild vector for Chagas disease in Chile and its epidemiological importance is being studied. To study the proportion of insects infected with Trypanosoma cruzi (tripano-triatomine index) in a zone with epidemiological risk in the Metropolitan Region of Chile, 492 specimens of triatoma spinolai were collected in 4 sites of a quarry zone, 14 kilometers north of Santiago. Their maturity and the presence of Trypanosoma cruzi in their intestinal contents were determined. Mean Tripano-triatomine index was 26.02ñ2 percent (range 0 to 34 percent in different sites). The proportion of infected insects increased along with the maturity and 58 percent of adult specimens were infected. There was a seasonal variation of the proportion of infected specimens being lower in march and June and higher in July and February. The studied zone has a potential epidemiological risk for the transmission of Chagas disease by Triatoma spinolai

Sensitivity of testis tumour cells to chemotherapeutic drugs: role of detoxifying pathways.

In contrast to most other types of cancer, metastatic testicular germ cell tumours (TGCT) are cured in most patients using cisplatin-based combination chemotherapy. The biochemical mechanisms underlying this sensitivity have not been defined. Drug detoxification can modulate response to chemotherapy in vivo and in vitro, and therefore we measured levels of glutathione (GSH), glutathione-S-transferase (GST) and both constitutive and cisplatin- and dexamethasone-induced levels of metallothionein (MT) in five human testis tumour cell lines. The levels were compared with those in five human bladder cancer cell lines and two cell lines with cisplatin resistance acquired in vitro. GSH levels were relatively low in the testis tumour cell lines, as might be expected in drug-sensitive cells, and there was a 77-fold increase in GSH levels in the cisplatin-resistant testis tumour cell line. GST levels were similar in the two cell types, while metallothionein levels were relatively high in the testis tumour cell lines. These data indicate that GSH may contribute to the sensitivity of TGCT to chemotherapy, and that GSH expression may be involved in the acquisition of cisplatin resistance in these tumours.

A double-blind, randomised comparison of the anti-emetic efficacy of two intravenous doses of dolasetron mesilate and granisetron in patients receiving high dose cisplatin chemotherapy.

This multicentre, double-blind, double-dummy, randomised trial was designed to compare the efficacy and safety of single intravenous doses of dolasetron mesilate and granisetron in the prevention of acute emesis and nausea due to high-dose (> or = 80 mg/m2) cisplatin. Single intravenous doses of 1.8 or 2.4 mg/kg of dolasetron mesilate or 3 mg of granisetron hydrochloride were administered in a volume of 50 ml over a 5-min period, beginning 30 min prior to cisplatin (> or = 80 mg/m2) administration. The number and timing of emetic episodes, time to administration of escape anti-emetic medication, severity of nausea by visual analogue scale (VAS), and safety were monitored for 24 h after the start of cisplatin-containing chemotherapy. Investigators' evaluations of overall efficacy and patients' satisfaction with therapy were recorded at the end of the 24-h study period. Of the 474 patients evaluable for efficacy, complete responses were achieved by 54, 47 and 48% of patients given dolasetron mesilate 1.8 mg/kg, dolasetron mesilate 2.4 mg/kg and granisetron, respectively. Statistically, treatment groups had comparable complete and complete plus major responses, times to first emesis, and use of escape medication; patient maximum nausea severity and treatment satisfaction ratings; and physician nausea severity and overall efficacy assessments. For the majority of efficacy endpoints, 1.8 mg/kg dolasetron mesilate produced numerically superior responses compared with the 2.4 mg/kg dose. Gender and prior chemotherapy were significant predictors of complete response; males and chemotherapy-naive patients had higher responses. The overall incidences of adverse events were comparable among the treatment groups; headache and diarrhoea were most common. In conclusion, 1.8 and 2.4 mg/kg of dolasetron mesilate and granisetron (3 mg) were equally effective in preventing nausea and vomiting induced by highly emetogenic cisplatin-containing chemotherapy. In addition, because no additional benefit was observed with 2.4 mg/kg of dolasetron mesilate and numerically greater responses were observed with the 1.8 mg/kg dose, the lower dose of 1.8 mg/kg is optimal for further clinical development.

OCT embedded sections of pathological specimens as a source of high quality RNA for reverse transcriptase/polymerase chain reaction.

OCT embedded cryostat sections of stored pathological specimens of non-Hodgkin's lymphoma were used to provide RNA. After reverse transcription to produce cDNA, the polymerase chain reaction was performed with primers for standard and variant forms of the CD44 molecule. Using Southern transfer and hybridisation with a probe specific for exon 4 of the CD44 gene, both standard and variant forms were visualised by autoradiography. This method was shown to be applicable to other gene products by using primers specific for the abl and bcr genes. This technique permits retrospective analysis of RNA from small amounts of stored pathological samples.

A comparison of a CB17 scid mouse model and the tetrazolium-dye assay using human haematological tumour cell lines.

Haematological tumours in the CB17 scid mouse produce a disseminated blood-borne disease analogous to that seen in humans. The CB17 scid mouse model has been applied to study the efficacy of chemotherapeutic agents on tumours. Using three human tumour-cell lines of haemopoietic origin (CCRF-CEM, Raji, HS-Sultan), we established disseminated tumours in scid mice and studied the in vivo response of these tumours to four chemotherapeutic agents (daunorubicin, idarubicin, ifosfamide, etoposide). The in vitro drug-resistance profiles of the same cell lines to these drugs were also determined by the tetrazolium-dye (MTT) assay. Differences were found in the patterns of resistance and sensitivity of the cell lines in the in vivo and in vitro systems tested. Since the scid mouse model determines the in vivo response of both host and tumour to cytotoxic agents, it may be more valid than the other models in determining drug resistance of haematological malignancies.

Second primary head and neck squamous cell carcinoma predicted by the glutathione S-transferase expression in healthy tissue in the direct vicinity of the first tumor.

BACKGROUND: Glutathione S-transferases (GST) are known to play a role in the detoxification of carcinogens. Individual isoenzymes of the alpha-, mu-, and pi-class vary in substrate specificities, tissue distribution, and activities among individuals. GST-pi expression has been shown to be increased in preneoplastic and neoplastic lesions. GST-mu is known to play a role in detoxification of epoxides released from cigarette smoke, and individuals with low GST-mu activity have a relatively high risk to develop smoking-related lung and laryngeal cancer. The occurrence of a second primary tumor (SPT) in the whole respiratory and upper aerodigestive tract is an important factor for mortality in head and neck squamous cell carcinoma (HNSCC), and, at present, there are no markers that are available to predict which patient has increased chances of developing an SPT. Risk-assessment by use of biomarkers, particularly the ones that can be obtained with noninvasive techniques, are of great value in predicting prognosis and hence possibly more aggressive treatment and follow-up in selected patient groups. EXPERIMENTAL DESIGN: In a nested case control study, 20 patients who had previous history of oral cancer were used; 10 of the 20 had developed an SPT, and the other 10 patients were minimally 7 years free of disease. The expression of GST-pi, GST-mu, and GST-alpha was immunohistochemically analyzed using apparently normal oral mucosa, free of tumor or dysplasia, obtained from the resection edges around the primary tumor. In another experiment, the three GST isoenzymes were immunohistochemically analyzed using exfoliated cells, obtained noninvasively from several sites of the upper aerodigestive tract of the apparently normal-looking mucosa of HNSCC patients (n = 25) and of control individuals (n = 10). RESULTS: The expression of all GST was significantly higher (p < 0.001) in the suprabasal and superficial layers of the mucosa at risk. Also, in cell scrapes of clinically healthy mucosa of HNSCC patients, we observed a significantly higher expression (p < 0.001) of GST-pi and GST-mu compared with their matched controls. For GST-alpha, we observed a more heterogenous expression pattern in these exfoliated cells. CONCLUSIONS: Expression of GST-pi, -mu, and -alpha in normal tissue in the direct vicinity of the first tumor seems to have predictive value for the development of an SPT.

Expression of mu class glutathione S-transferase correlates with event-free survival in childhood acute lymphoblastic leukemia.

Expression of the main classes (pi, mu, and alpha) of glutathione S-transferase (GST) was assessed in the blasts of children presenting with acute lymphoblastic leukemia using an immunohistochemical technique. Bone marrow trephine biopsies obtained at presentation from 71 cases were studied (42 boys, 29 girls; age range, 6 months-14 years; median age, 4 years) and expression was correlated with event-free survival. The period of follow-up was 12-108 months, during which time 21 patients (30%) relapsed. All the samples examined were negative for alpha class GST. Samples from 8 patients, all of whom remained in remission at the time of analysis, were found to be negative for pi class GST at presentation. Samples from 44 (patients were negative for mu class GST (62%); of these, 36 patients (82%) remained in remission. In comparison, of the 27 patients who were positive for mu class GST, only 14 (52%) remained in remission. Analysis of event-free survival demonstrated that expression of mu class GST predicts a 3-fold increased risk of relapse (95% confidence interval, 1.25-7.26). This risk factor appears to be independent of other recognized prognostic factors.

The C.B.17 scid mouse strain as a model for human disseminated leukaemia and myeloma in vivo.

Using the C.B.17 scid mouse strain, we have developed a model of disseminated leukaemia and myeloma using five human cell lines, CCRF-Cem, Molt-4, Raji, IM9 and HS-Sultan. Introduction of any of these cell lines by either an intravenous or an intraperitoneal route eventually kills the mouse due to leukaemia or myeloma cell load. Neoplastic cells can be found in the blood, liver and bone marrow. Intraperitoneal transfer produces a local solid tumour whereas intravenous transfer produces foci of neoplastic cells in the spine and brain. A single dose of melphalan is able to increase survival time from infection of a lethal dose of the T-cell leukaemia cell line, CCRF-Cem.

Glutathione S-transferase in bone marrow metastases of disseminated neuroblastoma.

Antisera to each of the three main cytosolic forms of glutathione S-transferase (GST; alpha, mu, and pi) has been used to characterise GST expression by metastatic neuroblastoma in bone marrow trephine biopsies taken from 15 patients at presentation and from five of this group at relapse. There was no correlation between expression of extra-nuclear alpha or mu GST and outcome, and no consistent pattern at relapse. Seven of eight expressing nuclear pi GST at presentation died of resistant disease. Three of five cases with no detectable nuclear pi class GST remain alive and disease free. The results provide no encouragement for further investigation of alpha or mu GST in this disease but larger studies of uniformly treated patients may show whether nuclear pi GST expression at presentation indicates likely relapse.

Expression of glutathione S-transferases in normal and malignant pancreas: an immunohistochemical study.

The glutathione S-transferases (GSTs) are a family of detoxification and metabolising enzymes, which have been linked with the susceptibility of tissues to environmental carcinogens and resistance of tumours to chemotherapy. Environmental carcinogens have been implicated in the pathogenesis of pancreatic carcinoma, which is also a tumour characterised by marked chemotherapeutic drug resistance. In this study 26 pancreatic adenocarcinoma and 12 normal pancreatic samples were examined immunohistochemically for expression of pi (acidic), alpha (basic), and mu (neutral) GST. Fourteen (54%) of the tumours expressed pi GST alone, two (8%) expressed both pi and alpha GST, and two (8%) showed immunoreactivity with alpha GST alone. In the normal pancreas the intralobular ducts and centroacinar cells expressed pi GST alone whereas the large ducts expressed both pi and alpha GST. The acinar cells showed immunoreactivity only with anti-alpha GST. Mu GST was not expressed by normal or malignant pancreas. Expression of pi GST by pancreatic carcinoma may be a marker of the malignant phenotype and be induced during neoplastic transformation. Alternatively it could possibly reflect cell of origin, suggesting that the tumour arises from the centroacinar cells or intralobular ducts, or both rather than the large ducts.

Efficacy of misoprostol in controlling indomethacin induced fecal blood loss in arthritic patients.

Indomethacin, a nonsteroidal anti-inflammatory drug, may cause gastric mucosal damage as shown by fecal blood loss. A randomized, double-blind, placebo-controlled, parallel group study was conducted to determine the effects of 400 mcg b.i.d. misoprostol, a synthetic prostaglandin E1 analog, on intestinal blood loss caused by 50 mg t.i.d. indomethacin. Forty-two arthritic patients, mean age 59 years, received indomethacin for 14 days. Those with baseline blood loss of at least 1.5 ml/day during the first 7 days were randomized to 400 mcg of misoprostol or placebo (days 8 to 14). Fecal blood loss was measured using 51Cr labelled red blood cell technique. Success was defined as a reduction in mean daily blood loss of at least 50% during the treatment period compared to mean daily blood loss during the baseline (pre-treatment) phase. The mean daily blood loss on treatment days 9-15 was not significantly reduced from baseline in either group. These data neither confirm nor deny the effectiveness of misoprostol in reducing fecal blood loss caused by indomethacin. The results may have been confounded by the administration of misoprostol twice daily while indomethacin was administered three times daily. In addition, fecal blood loss as an indicator of gastrointestinal mucosal damage is not a sensitive measure; it is characterized by poor reproducibility and wide fluctuations within individual responses. Inappropriate laboratory techniques may have further reduced the sensitivity and reliability of this procedure.

Phase II trials of tetrahydropyranyl-adriamycin (Pirarubicin) on renal and colon carcinoma, melanoma, and soft tissue sarcoma.

Eighty patients with measurable metastatic colon or renal cancer, melanoma, or sarcoma entered these Phase II studies. A dose of 25 mg/m2/day of Pirarubicin (THP) for 3 consecutive days every 4 weeks for the first patients, and then 20 mg/m2/day for 3 days every 3 weeks was given by i.v. push. These patients received 225 cycles for a median cumulative dose of 165 mg/m2 (range: 55-630). The mean number of cycles given was 2.8 (range: 1-8). Only 3 partial responses and 18 stable disease (22%) were observed. Hematologic toxicity was the main problem; it was responsible for one death and a 19% and 44% incidence of grade 3 and 4 WHO neutropenia, respectively. Alopecia was rare (4%). Chemotherapy was discontinued in three cases because of suspicion of cardiac toxicity, but only one patient had a significant drop in left ventricular ejection fraction at a cumulative THP dosage of 120 mg/m2. A lack of efficacy in renal and colon cancer and melanoma was presupposed and confirmed by these trials. Due to pretreatment with anthracycline in most patients, definite evaluation of THP in soft tissue sarcoma could not be given.

[Correlations between clinical pharmacodynamics and pharmacokinetics of cisplatin and etoposide]. / Corrélations entre la pharmacodynamie clinique et la pharmacocinétique clinique du cisplatine et de l'étoposide.

Currently, the dose of anticancer drugs is adjusted according to patient body surface area, although the best criterion for dose adjustment seems to be the plasma concentration of the drug, since a correlation has been established between plasma concentration and efficacy for several drugs. We report here similar results with etoposide and cisplatinum. The plasma concentration and the area under the curve (AUC) of etoposide and platinum (Pt) were higher in responders compared to non-responders, and etoposide clearance was higher in responders. The etoposide toxicity (assessed by the polymorphonuclear blood count) was higher in responders. There was a good correlation between the Pt concentration and creatininaemia. The AUC for Pt was significantly higher in patients with nausea and vomiting. There was no correlation between the infected dose of either drug and efficacy or toxicity. It is not possible to assign efficacy to either compound since they were injected simultaneously. We conclude that when the plasma etoposide or platinum concentrations are low, tumour response is unlikely.

Glutathione S-transferase activity and isoenzyme distribution in ovarian tumour biopsies taken before or after cytotoxic chemotherapy.

A study involving the measurement of glutathione S-transferase activities and isoenzyme distributions in human ovarian tumours has been carried out. These tumours have been obtained either at initial debulking surgery, prior to cytotoxic chemotherapy, or at second look laparotomy following chemotherapy. The response rates of these two groups to chemotherapy differ markedly, with patients who have relapsed following initial chemotherapy showing a reduction in response rates to subsequent chemotherapy. Analysis of these data show no statistically significant differences between the glutathione S-transferase activity or isoenzyme distribution in these two groups of patients. Significant differences were observed in the glutathione-S-transferase activities (GST) between tumours and normal ovaries. GST activities in pre-chemotherapy tumours (n = 33, P = 0.01) and post-chemotherapy tumours (n = 20, P = 0.001) where significantly higher than the GST activity in normal ovaries (n = 15). One feature was the expression of the basic isoenzyme which is expressed more in normal ovaries than in tumours. No differences in these parameters were observed in normal peritoneal tissue taken from patients before or after chemotherapy. These data do not support the hypothesis that changes in glutathione S-transferase enzyme activity or isoenzyme expression are major determinants of response to chemotherapy in ovarian tumours.