Differentiation of Edible Oils by Type Using Raman Spectroscopy and Pattern Recognition Methods

The application of Raman spectroscopy and pattern recognition methods to the problem of discriminating edible oils by type was investigated. Two-hundred and eighty-six Raman spectra obtained from 53 samples spanning 15 varieties of edible oils were collected for 90 s at 2 cm^-1 resolution. Employing a Whittaker filter, all Raman spectra were baseline corrected after removing the high-intensity fluorescent background in each spectrum. The Raman spectral data were then examined using the three major types of pattern recognition methodology: mapping and display, discriminant development and clustering. The 15 varieties of edible oils could be partitioned into five distinct groups based on their degree of saturation and the ratio of polyunsaturated fatty acids to monounsaturated fatty acids. Edible oils assigned to one group could be readily differentiated from those assigned to other groups, whereas Raman spectra within the same group more closely resembled each other and therefore would be more difficult to classify by type.

Raman Microspectroscopic Mapping with Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) Applied to the High-Pressure Polymorph of Titanium Dioxide, TiO2-II

The high-pressure, α-PbO₂-structured polymorph of titanium dioxide (TiO₂-II) was recently identified in micrometer-sized grains recovered from four Neoarchean spherule layers deposited between ∼2.65 and ∼2.54 billion years ago. Several lines of evidence support the interpretation that these layers represent distal impact ejecta layers. The presence of shock-induced TiO₂-II provides physical evidence to further support an impact origin for these spherule layers. Detailed characterization of the distribution of TiO₂-II in these grains may be useful for correlating the layers, estimating the paleodistances of the layers from their source craters, and providing insight into the formation of the TiO₂-II. Here we report the investigation of TiO₂-II-bearing grains from these four spherule layers using multivariate curve resolution-alternating least squares (MCR-ALS) applied to Raman microspectroscopic mapping. Raman spectra provide evidence of grains consisting primarily of rutile (TiO₂) and TiO₂-II, as shown by Raman bands at 174 cm^-1 (TiO₂-II), 426 cm^-1 (TiO₂-II), 443 cm^-1 (rutile), and 610 cm^-1 (rutile). Principal component analysis (PCA) yielded a predominantly three-phase system comprised of rutile, TiO₂-II, and substrate-adhesive epoxy. Scanning electron microscopy (SEM) suggests heterogeneous grains containing polydispersed micrometer- and submicrometer-sized particles. Multivariate curve resolution-alternating least squares applied to the Raman microspectroscopic mapping yielded up to five distinct chemical components: three phases of TiO₂ (rutile, TiO₂-II, and anatase), quartz (SiO₂), and substrate-adhesive epoxy. Spectral profiles and spatially resolved chemical maps of the pure chemical components were generated using MCR-ALS applied to the Raman microspectroscopic maps. The spatial resolution of the Raman microspectroscopic maps was enhanced in comparable, cost-effective analysis times by limiting spectral resolution and optimizing spectral acquisition parameters. Using the resolved spectra of TiO₂-II generated from MCR-ALS analysis, a Raman spectrum for pure TiO₂-II was estimated to further facilitate its identification.

Feasibility study for transforming spectral and instrumental artifacts for multivariate calibration maintenance

Frequently, a spectral-based multivariate calibration model formed on a particular instrument (primary) needs to predict samples measured on other (secondary) instruments of the same spectral type. This situation is often referred to as calibration maintenance or transfer. A new calibration maintenance approach is developed in this paper using spectral differences between instruments. In conjunction with a sample weighting scheme, spectral differences are piecewise (wavelength window) or full spectrum fitted with modeling terms (correction terms) such as polynomials and derivatives. Results demonstrating the potential usefulness of the new method using a near infrared (NIR) benchmark dataset are presented in this paper. The process does not need a standardization sample set measured in the primary condition. Thus, the new approach is a "hybrid" between the popular methods of extended inverted multiplicative signal correction (EISC) and direct standardization (DS) or piecewise DS (PDS). It is found that prediction errors reduce for samples measured in the secondary condition compared to those based on no calibration transfer. Prediction errors are also comparable to those from a full calibration in the secondary condition. In addition to instrument correction, an extension of the new approach is discussed (but not tested) for predicting new samples changing over time due to new chemical, physical, and environmental measurement conditions including individually or combinations of temperature, sample particle size, and new spectrally responding species.

Updating a synchronous fluorescence spectroscopic virgin olive oil adulteration calibration to a new geographical region

Detecting and quantifying extra virgin olive adulteration is of great importance to the olive oil industry. Many spectroscopic methods in conjunction with multivariate analysis have been used to solve these issues. However, successes to date are limited as calibration models are built to a specific set of geographical regions, growing seasons, cultivars, and oil extraction methods (the composite primary condition). Samples from new geographical regions, growing seasons, etc. (secondary conditions) are not always correctly predicted by the primary model due to different olive oil and/or adulterant compositions stemming from secondary conditions not matching the primary conditions. Three Tikhonov regularization (TR) variants are used in this paper to allow adulterant (sunflower oil) concentration predictions in samples from geographical regions not part of the original primary calibration domain. Of the three TR variants, ridge regression with an additional 2-norm penalty provides the smallest validation sample prediction errors. Although the paper reports on using TR for model updating to predict adulterant oil concentration, the methods should also be applicable to updating models distinguishing adulterated samples from pure extra virgin olive oil. Additionally, the approaches are general and can be used with other spectroscopic methods and adulterants as well as with other agriculture products.

Spectral multivariate calibration with wavelength selection using variants of Tikhonov regularization

Tikhonov regularization (TR) is a general method that can be used to form a multivariate calibration model and numerous variants of it exist, including ridge regression (RR). This paper reports on the unique flexibility of TR to form a model using full wavelengths (RR), individually selected wavelengths, or multiple bands of selected wavelengths. Of these three TR variants, the one based on selection of wavelength bands is found to produce lower prediction errors. As with most wavelength selection algorithms, the model vector magnitude indicates that this error reduction comes with a potential increase in prediction uncertainty. Results are presented for near-infrared, ultraviolet-visible, and synthetic spectral data sets. While the focus of this paper is wavelength selection, the TR methods are generic and applicable to other variable-selection situations.

Dietetic guidelines on food and nutrition in the secondary prevention of cardiovascular disease ? evidence from systematic reviews of randomized controlled trials (second update, January 2006)

AIM

To update dietetic guidelines based on systematic review evidence on dietary advice to prevent further events in people with existing cardiovascular disease (CVD) (secondary prevention).

METHODS

The Cochrane Library, MEDLINE and EMBASE were comprehensively searched to January 2005 for systematic reviews on aspects of diet and heart health. Reviews were included if they searched systematically for randomized controlled trials relating to diet and secondary prevention of CVD. Each review was critically appraised by at least two members of the UK Heart Health and Thoracic Dietitians Group. The quality and results of each review were discussed and summarized at a group meeting.

RESULTS

Evidence-based strategies that reduce cardiovascular events in those with CVD include reduction in saturated fat and substitution with unsaturated fats. Individuals who have suffered a myocardial infarction may also benefit from adopting a Mediterranean type diet and increasing intake of omega 3 fats, but it is not clear whether they are beneficial for all patients with CVD. There is no systematic review evidence to support the use of antioxidant vitamins supplements, low glycaemic index diets, or homocysteine lowering therapies in this group.

CONCLUSION

There remains good evidence that reducing saturated fat reduces morbidity in patients with CVD. This advice is consistent for most manifestations of CVD, with the addition of Mediterranean dietary advice and increased omega 3 fats for those who have had a myocardial infarction.

A phase I-II study of rituximab, ifosfamide, mitoxantrone and etoposide (R-IME) for B cell non-Hodgkin's lymphoma prior to and after high-dose chemotherapy and autologous stem cell transplantation (HDC-ASCT)

This phase I-II study describes the safety of rituximab, ifosfamide, mitoxantrone and etoposide (R-IME) as an induction regimen prior to high-dose chemotherapy and autologous stem cell transplantation (HDC-ASCT), and rituximab given post-HDC-ASCT for B cell non-Hodgkins's lymphoma. This study also measured the effect on disease burden and stem cell contamination. Patients with relapsed, refractory or poor risk B cell lymphomas were eligible. Patients were treated with two cycles of R-IME; all non-progressing patients under-went a third cycle and peripheral blood stem cell (PBSC) collection. Patients underwent HDC-ASCT and those patients in remission after HDC-ASCT were treated with four additional doses of rituximab. Tumor cell contamination was measured at baseline and in the PBSC. Serial immunoglobulin levels were measured. Patients were followed for time to treatment failure (TTF) and overall survival (OS). Thirty-two patients were enrolled. Thirty patients had at least stable disease after two cycles of R-IME. Twenty-nine underwent stem cell collection. The response rate to R-IME induction was 77% (20/26) with 35% (9/26) complete response(CR). Stem cell mobilization was successful in 93% (27/29) of patients. The response rate to R-IME induction and HDC-ASCT was 95% with a confirmed CR of 68%. Median follow-up was 28 months; the median TTFand OS have not been reached. There was a significant decline in stem cell tumor cell contamination and a significant decline in IgG without an increase in infections. Forty-three per cent of patients had transient neutropenia after post-transplant rituximab. R-IME is an effective cytoreductive and mobilization regimen. There appears to be a reduction in the number of lymphoma cells in the stem cell product and the toxicity is manageable.

Comparison of gemcitabine versus the matrix metalloproteinase inhibitor BAY 12-9566 in patients with advanced or metastatic adenocarcinoma of the pancreas: a phase III trial of the National Cancer Institute of Canada Clinical Trials Group

PURPOSE

To compare the selective matrix metalloproteinase inhibitor BAY 12-9566 with the nucleoside analog gemcitabine in the treatment of advanced pancreatic cancer.

METHODS

Patients with advanced pancreatic adenocarcinoma who had not previously received chemotherapy were randomly assigned to receive BAY 12-9566 800 mg orally bid continuously or gemcitabine 1,000 mg/m2 administered intravenously on days 1, 8, 15, 22, 29, 36, and 43 for the first 8 weeks, and then days 1, 8, and 15 of each subsequent 28-day cycle. The primary end point was overall survival; secondary end points were progression-free survival, tumor response, quality of life, and clinical benefit. The planned sample size of the study was 350 patients. Two formal interim analyses were planned.

RESULTS

The study was closed to accrual after the second interim analysis on the basis of the recommendation of the National Cancer Institute of Canada Clinical Trials Group Data Safety Monitoring Committee. There were 277 patients enrolled onto the study, 138 in the BAY 12-9566 arm and 139 in the gemcitabine arm. The rates of serious toxicity were low in both arms. The median survival for the BAY 12-9566 arm and the gemcitabine arm was 3.74 months and 6.59 months, respectively (P <.001; stratified log-rank test). The median progression-free survival for the BAY 12-9566 and gemcitabine arms was 1.68 and 3.5 months, respectively (P <.001). Quality-of-life analysis also favored gemcitabine.

CONCLUSION

Gemcitabine is significantly superior to BAY 12-9566 in advanced pancreatic cancer.

Randomized study of CODE versus alternating CAV/EP for extensive-stage small-cell lung cancer: an Intergroup Study of the National Cancer Institute of Canada Clinical Trials Group and the Southwest Oncology Group

PURPOSE

To determine whether an intensive weekly chemotherapy regimen plus thoracic irradiation is superior to standard chemotherapy in the treatment of extensive-stage small-cell lung cancer (ESCLC).

PATIENTS AND METHODS

Patients with ESCLC were considered eligible for the study if they were younger than 68 years, had a performance status of 0 to 2, and were free of brain metastases. Patients were randomized to receive cisplatin, vincristine, doxorubicin, and etoposide (CODE) or alternating cyclophosphamide, doxorubicin, vincristine/etoposide and cisplatin (CAV/EP). Consolidative thoracic irradiation and prophylactic cranial irradiation were given to patients responding to CODE and according to investigator discretion on the CAV/EP arm.

RESULTS

The fidelity of drug delivery on both drug regimens was equal, and more than 70% of all patients received the intended protocol chemotherapy. Although rates of neutropenic fever were similar, nine (8.2%) of 110 patients on the CODE arm died during chemotherapy, whereas one (0.9%) of 109 patients died on the CAV/EP arm. Response rates after chemotherapy were higher (P =.006) with CODE (87%) than with CAV/EP (70%). However, progression-free survival (median of 0.66 years on both arms) and overall survival (median, 0.98 years for CODE and 0. 91 years for CAV/EP) were not statistically different.

CONCLUSION

The CODE regimen increased two-fold the received dose-intensity of four of the most active drugs in small-cell lung cancer compared with the standard CAV/EP regimen while maintaining an approximately equal total dose. Despite supportive care (but not routine prophylactic use of granulocyte colony-stimulating factor), there was excessive toxic mortality with the CODE regimen. The response rate with CODE was higher than that of CAV/EP, but progression-free and overall survival were not significantly improved. In view of increased toxicity and similar efficacy, the CODE chemotherapy regimen is not recommended for treatment of ESCLC.

Randomized study of chemotherapy and surgery versus radiotherapy for stage IIIA non-small-cell lung cancer: a National Cancer Institute of Canada Clinical Trials Group Study

Thirty-one patients with stage IIIA (N2) non-small-cell lung cancer were randomized to receive radiotherapy alone or chemotherapy with cisplatin and vinblastine followed by surgery. Response rates to induction chemotherapy and radiotherapy were 50% and 53.3% respectively. Complete surgical resection was possible for 62.5% of patients. Median survival times were 16.2 and 18.7 months for radiotherapy alone and chemotherapy-surgery respectively (P = Ns), with no long-term improvement in survival seen with combined-modality treatment.

Randomized trial of intensive cyclophosphamide, epirubicin, and fluorouracil chemotherapy compared with cyclophosphamide, methotrexate, and fluorouracil in premenopausal women with node-positive breast cancer. National Cancer Institute of Canada Clinical Trials Group

PURPOSE

To determine the relative efficacy of an intensive cyclophosphamide, epirubicin, and fluorouracil (CEF) adjuvant chemotherapy regimen compared with cyclophosphamide, methotrexate, and fluorouracil (CMF) in node-positive breast cancer.

PATIENTS AND METHODS

Premenopausal women with node-positive breast cancer were randomly allocated to receive either cyclophosphamide 100 mg/m2 orally days 1 through 14; methotrexate 40 mg/m2 intravenously (i.v.) days 1 and 8; and fluorouracil 600 mg/m2 i.v. days 1 and 8 or cyclophosphomide 75 mg/m2 orally days 1 through 14; epirubicin 60 mg/m2 i.v. days 1 and 8; and fluorouracil 500 mg/m2 i.v. days 1 and 8. Each cycle was administered monthly for 6 months. Patients administered CEF received antibiotic prophylaxis with cotrimoxazole two tablets twice a day for the duration of chemotherapy.

RESULTS

The median follow-up was 59 months. One hundred sixty-nine of the 359 CMF patients developed recurrence compared with 132 of the 351 CEF patients. The corresponding 5-year relapse-free survival rates were 53% and 63%, respectively (P = .009). One hundred seven CMF patients died compared with 85 CEF patients. The corresponding 5-year actuarial survival rates were 70% and 77%, respectively (P = .03). The rate of hospitalization for febrile neutropenia was 1.1% in the CMF group compared with 8.5% in the CEF group. There was one case of congestive heart failure in a patient who received CMF compared with none in the CEF group. Acute leukemia occurred in five patients in the CEF group.

CONCLUSION

The results of this trial show the superiority of CEF over CMF in terms of both disease-free and overall survival in premenopausal women with axillary node-positive breast cancer.

Phase I studies of fluorouracil, doxorubicin and vinorelbine without (FAN) and with (SUPERFAN) folinic acid in patients with advanced breast cancer

PURPOSE

The Breast Cancer Site Group of the National Cancer Institute of Canada - Clinical Trials Group (NCIC-CTG) undertook two parallel phase I studies to determine the maximum tolerated dose (MTD) and recommended phase II dose of vinorelbine in combination with doxorubicin and fluorouracil (with or without folinic acid) in metastatic breast cancer.

METHODS

Cohorts of five patients were to receive: (a) fluorouracil 500 mg/m2 and doxorubicin 50 mg/m2 on day 1 only and escalating doses of vinorelbine (15, 20, 25, 30 mg/m2) on days 1, 8 and 15 every 3 weeks (FAN regimen), or (b) fluorouracil 340 mg/m2 and folinic acid 200 mg/m2 on days 1, 2, 3, 4 and 5, doxorubicin 40 mg/m2 on day 1 only and escalating doses of vinorelbine (15, 20, 25, 30 mg/m2) on day 1 and again on day 5 every 4 weeks (SUPERFAN regimen). Eligibility included measurable or evaluable metastatic breast cancer and having received neither previous chemotherapy for metastatic disease nor anthracycline-containing adjuvant therapy.

RESULTS

Of 26 and 12 patients enrolled in the FAN and SUPERFAN regimens, 26 and 12 were evaluable for toxicity and 21 and 9 for response, respectively. Median ages were 60.3 years (41-71 years) and 64.2 years (51-73 years). Both regimens required amendment after the first cohort with an original day- 15 vinorelbine dose omitted from the FAN regimen and more prolonged nadir granulocyte counts allowed. Myelosuppression was dose limiting. MTDs in the FAN and SUPERFAN regimens were vinorelbine 25 mg/m2 and 20 mg/m2. Other toxicities included mucositis, septicemia and febrile neutropenia. Peripheral neuropathy and constipation were mild. Of the 21 FAN patients evaluable for response, 3 (14%) had complete responses and 7 (33%) had partial responses, for an overall response rate of 48%; 9 (43%) had stable disease and 2 (9%) had progressive disease as their best response. Of the nine SUPERFAN patients evaluable for response, none had a complete response. There were two (22%) with partial responses, and six (67%) had stable disease and one (11%) had progressive disease as their best response.

CONCLUSIONS

The SUPERFAN regimen was too toxic to pursue even at the lowest dose. The recommended phase II starting dose for the FAN regimen was vinorelbine 20 mg/m2. Although these were phase I studies response rates in evaluable patients were less than expected and toxicity did not allow the use of as much vinorelbine in the combinations as had been anticipated. The limited response data from our study would imply that combining vinorelbine with more toxic agents may not enhance response rates and may defeat the advantage of tolerability, especially in elderly patients.

Myosin light-chain phosphatase

1. A method for the isolation of a new enzyme, myosin light-chain phosphatase, from rabbit white skeletal muscle by using a Sepharose-phosphorylated myosin light-chain affinity column is described. 2. The enzyme migrated as a single component on electrophoresis in sodium dodecyl sulphate/polyacrylamide gel at pH7.0, with apparent mol.wt. 70000. 3. The enzyme was highly specific for the phosphorylated P-light chain of myosin, had pH optima at 6.5 and 8.0 and was not inhibited by NaF. 4. A Ca2+-sensitive 'ATPase' (adenosine triphosphatase) system consisting of myosin light-chain kinase, myosin light-chain phosphatase and the P-light chain is described. 5. Evidence is presented for a phosphoryl exchange between Pi, phosphorylated P-light chain and myosin light-chain phosphatase. 6. Heavy meromyosin prepared by chymotryptic digestion can be phosphorylated by myosin light-chain kinase. 7. The ATPase activities of myosin and heavy meromyosin, in the presence and absence of F-actin, were not significantly changed (+/- 10%) by phosphorylation of the P-light chain.