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PubMed1986

Quantitative genetic variation in the skeleton of the mouse: II. Description of variation within and between inbred strains.

Variation in the skeletons of over 400 male and female mice from 12 genotypes was investigated by using multivariate statistical methods. A series of discriminant functions explains the differences in the shape of six bones: mandible, os coxae, femur, tibia-fibula, scapula, and humerus. The anatomical features of bone shape described by these functions are summarized together with illustrations of the typical shapes of each bone from the 12 genotypes. Variability within genotypes was investigated by using the Mahalanobis D2 distance--a measure of the difference between two points representing multivariate data--from the group mean. A series of variants were detected ranging from grossly abnormal bones to bones showing subtle differences localized to specific regions. Examples of the variants found are illustrated.

Animals↗
PubMed1998

Clinical and pharmacokinetic risk factors for high-dose methotrexate-induced toxicity in children with acute lymphoblastic leukemia--a logistic regression analysis.

The clinical and pharmacokinetic risk factors for toxicity after high-dose methotrexate (MTX) in children with acute lymphoblastic leukemia were evaluated using a multivariate statistical analysis. Plasma samples were collected after 44 24-h infusions of MTX (5 or 8 g/m2) in 13 children (age 3.3-12.9 years) and subsequently analyzed by HPLC to determine the MTX and 7-hydroxymethotrexate (7-OHMTX) concentrations. Toxicity was evaluated according to the WHO criteria. Severe toxicity was not observed. Oral mucositis (WHO grade > or = 1) was significantly related to a high plasma MTX concentration at 28 h after starting the infusion (p = 0.013), a low ratio of plasma 7-OHMTX/MTX at 66 h after starting the infusion (p = 0.049), and a slow clearance of MTX (p = 0.048). The risk of leukopenia (WHO grade > or = 2) increased significantly with the number of courses (p = 0.02). Increasing age and a long exposure to a high MTX concentration in plasma (AUC) were significant risk factors (p = 0.047 and p = 0.009, respectively) for developing elevated liver enzymes (ALAT) (WHO grade > or = 2). This study shows how a statistical model can be used to identify clinical and pharmacokinetic factors that may influence MTX-induced toxicity. The therapeutic ratio could thereby potentially be improved.

Bone Marrow↗
PubMed2001

Prognostic factors in ossiculoplasty: a statistical staging system.

OBJECTIVE: To determine factors that predict hearing results using a standard prosthesis system. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: All patients undergoing ossiculoplasty with the Dornhoffer HAPEX partial and total ossicular replacement prostheses (PORP and TORP) from February 1995 to May 1999 who had documented postoperative follow-up and no congenital atresia or stapes fixation. A total of 185 patients (200 ears), 105 men and 80 women, were evaluated. INTERVENTIONS: Ossiculoplasty with the Dornhoffer prostheses. MAIN OUTCOME MEASURES: Hearing results using a four-frequency pure-tone average air-bone gap (PTA-ABG). Multivariate statistical analysis determined the effect of mucosal status, ossicular chain status, and type of reconstruction techniques on hearing. RESULTS: The PTA-ABGs were 13.4+/-8.1 dB and 14.0+/-8.4 dB for the PORPs (n = 114) and TORPs (n = 86), respectively, which was not statistically different. When the malleus handle was present (n = 126), the PTA-ABG was 11.6+/-6.2 dB, compared with 16.9+/-10.1 dB when it was absent (n = 74), which was statistically significant (p < 0.05). Mucosal fibrosis, drainage, revision ear surgery, and type of surgical procedure had a significant detrimental impact on hearing. The type of pathologic process (perforation vs. cholesteatoma) had no significant impact on hearing results. CONCLUSIONS: The revised staging system, the Ossiculoplasty Outcome Parameter Staging Index, more adequately predicts hearing outcome in this series of 200 cases.

Adolescent↗
PubMed1999

Variety identification in maize lines via capillary electrophoresis of zeins in isoelectric acidic buffers.

Zeins (the prolamins or seed storage proteins in maize) have been used to characterize and identify different genotypes. Zeins were fractionated by capillary zone electrophoresis in acidic, amphoteric buffers, which represent a medium of moderate conductivity and are thus compatible with higher voltage gradients. The running buffer consisted of 40 mM isoelectric aspartic acid, in presence of 6 M urea and 0.5% hydroxyethyl cellulose (apparent pH: 3.8; pI in the absence of urea: 2.77). Thirty-one different zein peaks were mapped out of a total of 21 different maize genotypes. Each of them typically exhibited seven to twelve peaks, with some genotypes showing up to 20 zein bands. Due to slightly changing elution times, caused by a lack of reproducibility of the electroendoosmotic flow in uncoated silica surfaces, correct peak assignment and alignment among different runs was obtained by multivariate statistical analysis. The present method compares well, both in resolution and total number of peaks, with current protocols adopted for screening of maize inbreds, which consist of isoelectric focusing in agarose gels.

Buffers↗
PubMed1995

Quantitative cytopathology of endometrial lesions.

Morphometric and multivariate statistical methods were used to discriminate endometrial carcinoma from benign cells in cytologic studies. Clumps of epithelial cells that appeared most diagnostically relevant were selected from aspirated samples of 70 endometrial cancer patients. The cells' cytologic character was reduced to a combination of five quantitative parameters--nuclear size, degree of anisokaryosis, nuclear from index, homogeneity of nuclear chromatin texture, and regularity of nuclear arrangement. The 5-variate cluster analysis demonstrated that the 70 cases could be classified into three definite groups: Group A (17 cases) was characterized by cells of small nuclear size, slight anisokaryosis, homogeneous chromatin texture, and regular nuclear arrangement; Group C (12 cases) by cells of large nuclear size, marked anisokaryosis, heterogeneous chromatin texture, and irregular nuclear arrangement; and Group B (41 cases) by cells of intermediate parameter values. Group C was derived from 10 cases of adenocarcinoma and 2 of atypical hyperplasia, while Groups A and B were not derived from any cases of malignancy. The computer-assisted morphometric statistical method can objectively classify the endometrial cells into malignant and benign, with improved validity and reproducibility. The cytopathologic finding, if detected by this method, may serve as a surrogate endpoint biomarker.

Cluster Analysis↗
PubMed2003

Factors predicting human papillomavirus clearance in cervical intraepithelial neoplasia lesions treated by conization.

OBJECTIVE: The objective was to identify the factors, if any, that may predict long-term results of CIN treatment and HPV clearance/persistence after locally excisional therapy. METHODS: A series of 252 women with CIN lesions treated by conization were subjected to sequential HPV detection by repeated PCR during the prospective posttreatment follow-up. Factors predicting viral clearance during the follow-up (10.26 months) were elaborated using univariate and multivariate statistical techniques applied on epidemiological, clinical and biological data of the lesions. RESULTS: Sensitivity of the PAP test in detecting high-grade lesions was 93.9%, and specificity 27.3%. Odds ratio for having CIN 3/Stage IA1 squamous cervical cancer in the cone with HSIL PAP test was 5.69; 77.8 and 22.2% residual disease were found among PCR-positive and -negative cases, respectively. HPV DNA was negative in 74/252 (29.8%) samples at the first PCR. Multivariate logistic regression analysis showed that HPV 16 was an independent explanatory factor for high-grade CIN (P = 0.0001). HPV clearance increased to 63.5% at completion of the follow-up, corresponding to the monthly clearance rate of 5.27%. In Kaplan-Meier analysis, the highly significant (P = 0.0001) predictors of HPV clearance/persistence were age, lesion grade in the biopsy, lesion grade in the cone, volume of the cone, length of active sexual life, and involvement of endocervical margin (P = 0.0013). In chi-square tests, high-risk HPV type (P = 0.001) was such a predictor. In multivariate (Cox) model, the significant independent predictors of HPV clearance were involved endocervical margin (P = 0.001), lesion grade in the cone (P = 0.004), high-grade lesion in the colposcopic biopsy (P = 0.023), age (P = 0.029), and HSIL in PAP smear (P = 0.029). CONCLUSIONS: These data suggest that posttreatment follow-up should include both the PAP test and HPV detection techniques for early detection of any patients at increased risk for disease recurrence and progression, because of persistent oncogenic HPV types.

Adolescent↗
PubMed1999

Aortic valve replacement in the octogenarians: perioperative outcome and clinical follow-up.

OBJECTIVES: To determine long-term results of aortic valve replacement (AVR) in patients 80 years old or older, and assess the factors influencing perioperative outcome. METHODS: Data were reviewed on 83 consecutive octogenarians, undergoing aortic valve replacement between 1992 and 1997. There were 66 women and 17 men (mean age: 82.8 years). Fifty-seven patients (69%) were in New York Heart Association (NYHA) class III-IV and six had previous myocardial infarction. Three patients had previous percutaneous aortic valvuloplasty. There were 19 urgent procedures (23%). Coronary artery bypass grafting (CABG) was performed on 21 patients (25%). Possible influence of preoperative and operative variables on early and late mortality was performed with univariate and multivariate statistical analysis, and survival was estimated with the Kaplan-Meier method. RESULTS: Operative mortality was 13% (9% for AVR, 24% for AVR-CABG). Postoperative complications were respiratory failure in 19 patients, atrial fibrillation in 19, hemodialysis in four, myocardial infarction in four and stroke in two patients. Five patients required pacemaker insertion for permanent atrioventricular block. Median hospital stay and intensive care unit stay were 19.8 +/- 12.2 days and 7.9 +/- 3.4 days, respectively. Multivariate predictors of hospital death (P < 0.05) were percutaneous aortic valvuloplasty, NYHA class IV, and urgent procedure. Mean follow-up was 26.5 months. Survival at 1, 2, and 5 years was 98.5 +/- 1.4% (63 patients at risk), 93.4 +/- 3.2% (47 patients at risk), and 78.2 +/- 6.9% (six patients at risk), respectively. Preoperative myocardial infarction and urgent procedure were independent predictors of late death. At most recent follow-up, 91% were angina free and 81% were in class I-II. CONCLUSIONS: Aortic valve replacement in octogenarians can be performed with acceptable mortality. These results stress the importance of early operation on elderly patients with aortic valve disease. Both long-term survival and functional recovery are excellent.

Aged↗
PubMed2026

Extent of resection as an independent predictor of survival for patients with glioblastoma as defined by the new WHO 2021 classification.

OBJECTIVE: Extent of resection (EOR) has previously been demonstrated to have an impact on survival in patients with glioblastoma (GBM). However, with the World Health Organization (WHO) 2021 reclassification of GBMs based on IDH-mutation status, patients with "IDH-mutant GBMs," who typically survive long term, were reclassified as WHO grade 4 IDH-mutant astrocytomas and removed from the GBM taxonomy. Therefore, it is unknown whether the previously reported impact of resection on survival was a false-positive result due to the inclusion of the less aggressive IDH-mutant tumors in previous datasets. This study aimed to determine the extent to which EOR remains an independent predictor of survival in patients with WHO 2021 GBM after the reclassification of IDH-mutant grade 4 astrocytomas. METHODS: All cases of GBM tumors (based on the pre-2021 GBM classification) that were newly diagnosed between 2005 and 2021 were identified in our institutional database and subsequently reclassified based on the updated WHO 2021 criteria using IDH status. Multivariable statistical analyses of demographic information, survival time, and EOR based on volumetric MRI were performed to determine the independent predictors of survival for the whole group of patients and for IDH-wildtype GBM patients exclusively. Additional analyses were performed to identify an EOR threshold for improvement in survival. RESULTS: Of the 523 tumors classified as GBM based on the pre-2021 taxonomy, 52 (9.9%) cases were reclassified as WHO grade 4 IDH-mutant astrocytomas, and the median survival of patients in this group was 7.9 years, whereas median survival of the IDH-wildtype GBM patients was 1.4 years. Multivariate analyses of the whole group demonstrated that IDH-mutant astrocytomas were associated with reduced hazard of death. In both the whole group (n = 523) and in IDH-wildtype GBMs (n = 471), higher EOR of the contrast-enhancing (CE) tumor was associated with reduced hazard of death, whereas older age or male sex was associated with increased hazard of death. Because most patients (90%) had high EOR values (> 81%), a statistically meaningful EOR threshold could not be established. CONCLUSIONS: These analyses demonstrated that EOR of the CE tumor is an independent predictor of survival and that greater EOR is associated with improved survival in WHO 2021 IDH-wildtype GBMs even after excluding grade 4 IDH-mutant astrocytomas. However, an absolute EOR threshold below which resection did not improve survival could not be established, raising concerns about prior cutoff assessments.

Humans↗
PubMed1982

Quantitative correlations amongst alkaline DNA fragmentation, DNA covalent binding, mutagenicity in the Ames test and carcinogenicity, for 21 compounds.

21 compounds from different chemical classes were quantitatively compared for their carcinogenic potency according to 4 parameters: (1) potency in inducing covalent binding with DNA in vivo; (2) potency in inducing alkaline DNA fragmentation after treatment in vivo; (3) acute toxicity; (4) mutagenic potency in the Ames test. Establishing well-defined conditions for normalization of the different types of data and determination of the set that had to be submitted to statistical analysis appeared to be a difficult task, for which only compromise solutions were possible. A statistical analysis of the data suggested that all parameters considered were correlated with carcinogenic potency. However, we found that there are about 3 chances to 1 that carcinogenicity is better correlated with DNA covalent binding in vivo than it is to mutagenicity in the Ames test. With due precautions, even acute toxicity could be of predictive value. DNA adducts and DNA fragmentation, both in vivo, appeared to be 2 parameters strongly correlated between them. From a multivariate statistical analysis it appeared that: (1) a significant improvement of quantitative predictability is in principle obtainable with a battery of short-term test; and (2) the improvement is obtainable only if the short-term tests considered, while all correlated with carcinogenicity, are relatively independent amongst themselves.

DNA↗
PubMed2007

Arthroscopic rotator cuff repair with and without subacromial decompression: a prospective randomized study.

PURPOSE: Our purpose was to evaluate the role of subacromial decompression in the arthroscopic repair of full-thickness rotator cuff tears in a prospective randomized clinical study. METHODS: Arthroscopic cuff repair was performed in 80 patients with a full-thickness rotator cuff tear. They were divided into 2 groups comprising 40 patients each. In group 1 arthroscopic rotator cuff repair was performed with subacromial decompression. In group 2 the repair was performed without decompression. Rotator cuff tears were repaired via metal suture anchors for tendon-to-bone repair, side-to-side repair, or a combination of the 2 techniques. Results were evaluated by use of the Constant score normalized for age and gender, as well as the Disabilities of the Arm, Shoulder and Hand (DASH) and Work-DASH self-administered questionnaires. On analyzing the results at 2 years' follow-up, we considered the following independent variables: age; gender; dominance; location, shape, area, retraction, and reducibility of cuff tear; fatty degeneration; involvement of subscapularis tendon; treatment of biceps tendon; rotator cuff repair technique; and type of acromion. A univariate and multivariate statistical analysis was performed to determine which variables were independently associated with the outcome. RESULTS: Comparison between the groups did not show significant differences for each variable considered. The overall results for the Constant score were 103.6 points in group 1 and 96.1 points in group 2; those for the DASH score were 18.2 points and 23.1 points, respectively; and those for the Work-DASH score were 23.7 points and 26.2 points, respectively. Univariate and multivariate analysis showed that the following variables significantly and independently influenced the outcome: age; shape, retraction, and reducibility of cuff tear; fatty degeneration; involvement of subscapularis; and repair technique. Subacromial decompression did not influence the outcome significantly for each scoring system considered. CONCLUSIONS: At short-term follow-up, subacromial decompression did not seem to significantly affect the outcome of arthroscopic rotator cuff repair. Longer follow-up studies will be necessary to confirm the clinical relevance of these observations. LEVEL OF EVIDENCE: Level I, randomized controlled trial with no significant difference but narrow confidence intervals.

Aged↗
PubMed2004

Recurrence pattern of squamous cell carcinoma of the thoracic esophagus after extended radical esophagectomy with three-field lymphadenectomy.

BACKGROUND: Extended radical esophagectomy with three-field lymphadenectomy for patients with thoracic esophageal cancer has been shown to be effective. But even if this operation is performed, some patients still experience relapse of the disease. The purpose of this study was to clarify the pattern and timing of recurrence after extended radical esophagectomy. STUDY DESIGN: Recurrence of esophageal squamous cell carcinoma was examined in 171 of 174 patients who underwent extended radical esophagectomy with three-field lymphadenectomy. Recurrence patterns were classified as locoregional (at the site of the primary tumor, the anastomotic site, or the lymph nodes), hematogenous, and other (pleura or site of gastrostomy). Factors associated with recurrence were identified using univariate and multivariate statistical methods for survival analysis. RESULTS: The overall 5-year survival rate was 55.6%. Recurrence was recognized in 74 patients (43.3%). The median disease-free interval until recurrence was 11 months. Thirty patients (17.5%) developed a locoregional recurrence, and 24 (14.0%) developed a hematogenous recurrence. Five patients (2.9%) developed both recurrences simultaneously and were classified as hematogenous recurrences. Of 30 patients with cervical lymph node metastasis, recurrent disease was recognized in 19 patients (63.3%). In multivariate analysis of 160 patients, the depth of invasion and pM-lym (cervical or celiac lymph node metastasis) were significant factors for locoregional recurrence; the depth of invasion and number of lymph node metastases at operation were significant factors for hematogenous recurrence. Survival time for patients with hematogenous recurrence (median 16 months) was significantly shorter than that of patients with locoregional recurrence (median 25.5 months). CONCLUSIONS: Locoregional recurrence is associated mainly with the extent of the local tumor and lymph node metastasis; hematogenous recurrence is not only associated with tumor stage but also with the tumor's oncologic behavior.

Aged↗
PubMed2004

[Quality of life in unipolar depressive and bipolar affective patients].

OBJECTIVE: To assess subjective quality of life (QOL) of subjects with unipolar depressive and bipolar affective disorders. METHODS: 153 consecutive psychiatric in-patients were assessed with standardized interviews. Prior to discharge QOL was assessed with WHOQOL-bref. With the help of multivariate statistics, the effect of illness and biographical factors on four domains of QOL (physical health, psychological, social relationships and environment) was analyzed. RESULTS: 103 patients suffered from unipolar depression, 51 from bipolar affective disorder (30 fulfilled criteria for a mixed or pure manic episode). With the exception of the domain environment for (mixed) manic patients, all patients reported lower QOL in all domains than was reported for the general population according to the German test manual. Multivariate analyses revealed that the chosen variables explained between 11.1 % (social relationships) and 33.6 % (psychological) of the variance of the QOL domains. The domains "psychological" and "environment" were first of all explained by the presence of a (mixed) manic episode, while the best variable to predict "physical health" was presence of comorbid neurotic disorder. The depression score had little additional effects on QOL. CONCLUSIONS: We found little support that the QOL domains of the WHOQOL-bref in affective disorder are only hidden depression scores, as has been argued before. Therefore, QOL could be an interesting construct to better understand differences between subjective evaluation and (supposedly) objective psychopathology in bipolar affective disorders.

Adult↗
PubMed2006

Determination of PM2.5 sources using time-resolved integrated source and receptor models.

Multivariate statistical techniques are applied to particulate matter (PM) and meteorological data to identify the sources responsible for evening PM spikes at Sunland Park, NM (USA). The statistical techniques applied are principal components analysis (PCA), redundancy analysis (RDA), and absolute principal components scores analysis (APCSA), and the data evaluated are 3-h average (6-9 p.m.) PM(2.5) mass and chemical composition and 1-h average PM(2.5) and PM(10) mass and environmental data collected in the winter of 2002. Although the interpretation of the data was complicated by the presence of sources which are likely changing in time (e.g. brick kilns), the multivariate analyses indicate that the evening high PM(2.5) is associated with burning-activities occurring to the south of Sunland Park, and these emissions are characterized by elevated Sb, Cl(-), and elemental carbon; approximately 68% of the PM(2.5) mass can be attributed to this source. The PM(10) evening peaks, on the other hand, are mainly caused by resuspended dust generated by vehicular movements south of the site and transported by the local terrain-induced drainage flow.

Air Pollutants↗
PubMed2003

A method for monitoring the surface conservation of wooden objects by Raman spectroscopy and multivariate control charts.

The principles of quality control and multivariate statistical analysis were applied to the monitoring of the conservation state of wooden works of art. Three degradation processes (exposure to a wet atmosphere, to an acidic attack, and to UV light) were simulated on the surface of wooden boards of the XVI century and were monitored by the use of Raman spectroscopy. The resulting spectra were treated by principal component analysis, which allowed reduction of the system dimensionality. The relevant principal components were used to build multivariate control charts, namely, the Shewhart, CUSUM, and SMART (simultaneous scores monitoring and residual tracking) control charts. The Shewhart charts allowed identification of the effects due to the degradation processes. The CUSUM charts permitted identifcation of the exact moment in which the degradation treatment was started. The SMART charts provided a synthetic description of the conservation state of the wooden surface by means of only two charts: the T2 Hotelling and the DModX charts.

Journal Article↗
PubMedDate not supplied

Factors predicting progression of IgA nephropathies.

The difficulties in defining the natural history of primary IgA nephropathy (IgAN) depend upon the pre-selection of patients for renal biopsy, a true individual variability - ranging from asymptomatic to rapidly progressive forms - as well as the use of different classifications of the renal lesions and statistical analyses sometimes carrying incorrect modalities. Long-term natural history studies have demonstrated that the rate of progression has an extremely wide range, from 5 to 25% after 10 years and 25-50% at 20 years, and complete remission is reported as well in 5 to 30% of cases. A geographic variability has been confirmed in a tri-continental study, explainable only partly by the earlier referral. Among the factors predicting progression, the more frequent in cohorts showing worse actuarial survival at 10 years are those associated with the advanced phases of renal damage, as increased creatinine level, arterial hypertension and nephrotic range proteinuria. A multivariate statistical approach showed the relevance of proteinuria during follow-up (percent duration of massive proteinuria or proteinuria at 1 year) more than proteinuria at the onset. Mean blood pressure value (MAP) and proteinuria during follow-up were independent predictors of end-stage CKD. Note the predictive value of severe microscopic hematuria in several studies. As far as histological features are concerned, strong independent predictors of progression at Cox multivariate analysis are the severity of glomerular sclerosis and interstitial fibrosis. The presence of crescents was a risk factor in almost all studies at univariate analysis, but did not maintain a significant predictor value at multivariate analysis. Conversely the association between crescents and tuft adhesions, possibly resulting from previous segmental necrosis, was found to be a significant risk factor. The extent of mesangial proliferation and parietal expansion of deposits was not significantly associated to unfavourable prognosis at multivariate analysis. The analysis of risk factors for progression of IgAN related to Henoch-Schoenlein purpura (HSP) failed to demonstrate any prognostic value for the presence and severity of extra-renal signs of vasculitis or presence of triggering factors. At multivariate Cox analysis, age and mean proteinuria during follow-up were powerful independent prognostic predictors. Proteinuria at baseline was not significantly related to renal progression, nor were hypertension or impaired renal function at onset. It is of interest that data at onset and at renal biopsy (renal function impairment, hypertension, nephrotic-range proteinuira) were not significantly related with renal detrimental progression. Neither had prognostic value the finding of crescents involving up to 75% of glomeruli.

Adult↗
PubMed2006

Prognostic factors in patients with unresectable locally advanced pancreatic adenocarcinoma treated with chemoradiation.

BACKGROUND: Although patients with locally advanced pancreatic cancer (LAPC) have an extremely poor prognosis, they are a heterogeneous group. Prognostic factors are inadequately defined for disease-free survival and overall survival in patients with LAPC who are receiving chemoradiation, so more definitive prognostic factors would be very useful for designing clinical trials. METHODS: Between December 1993 and July 2005, 247 patients with nonmetastatic LAPC were treated at M. D. Anderson Cancer Center (Houston, Tex) with concurrent chemoradiation (CRT). Median radiation dose was 30 Gy (range, 15-52.2 Gy). Radiosensitizers included 5-fluorouracil (54%), gemcitabine (33%), and capecitabine (13%). Actuarial univariate and multivariate statistical methods were used to determine significant prognostic factors for disease-free survival and overall survival. RESULTS: Median follow-up was 4.3 months (range, 1-63 months). Median disease-free survival and overall survival were 4.2 months and 8.5 months, respectively. On univariate analysis, prognostic factors for improved disease-free survival were a Karnofsky performance scale (KPS) status of >80 (P < .01) and a hemoglobin (Hgb)level at presentation of >/=12 (P = .03). On multivariate analysis, KPS was the only independent prognostic factor for disease-free survival. Median disease-free survival was 4.9 months among patients with a KPS score of >80 and was 3.9 months among those with a KPS score of </=80. On univariate analysis, prognostic factors for improved overall survival were an Hgb level of >/=12 (P = .02), KPS>80 (P < .001), and <5% weight loss (P = .03). On multivariate analysis, Hgb and KPS were independent prognostic factors for overall survival. CONCLUSIONS: In the current study, KPS score was an independent prognostic factor for disease-free and overall survival among patients treated with chemoradiation for LAPC. The pretreatment Hgb level was an additional independent prognostic factor for overall survival.

Adenocarcinoma↗
PubMed2002

Lichens as integrating air pollution monitors.

In this work an attempt to combine the results of lichen mapping with the quantitative levels of certain trace elements in Hypogymnia physodes (L.) Nyl. collected on a national scale is presented. An Index of Atmospheric Purity (IAP) was calculated using a simple method of mapping lichens based on the assessment of the cover and frequency of crustose, foliose and fruticose lichens on different tree species. For determination of trace elements in lichens k0-instrumental neutron activation analysis was used. From the IAP results it can be concluded that the epiphytic lichen flora look quite poor with more than 70% of the territory in the fourth and third classes, which represent highly polluted and moderately polluted air. By comparing IAP results with elemental levels in H. physodes using multivariate statistical methods it was found that the elemental levels do not have a direct negative effect on the diversity of lichens but can help in identification of the type of possible pollution sources and their origin.

Air Pollutants↗
PubMed1999

Multivariate analysis of metal concentration profiles in mushrooms.

The present work is an overview of the levels of contamination of 92 macromycetes by 15 metals. Data were collected around Paris (France) in 1989 and 1990. A progressive approach involving the use of univariate followed by multivariate statistical analyses allowed to fully exploit the resulting data matrix. Thus, conclusions regarding the origin of the metals, the toxicological implications and the possible use of mushrooms as environmental markers of pollutions are drawn.

Ascomycota↗