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PubMedDate not supplied

CT differentiation between necrotic and nonnecrotic small bowel in closed loop and strangulating obstruction.

BACKGROUND: The purpose of this study was to evaluate computed tomographic (CT) findings for predicting the presence of intestinal necrosis in patients with closed loop and strangulating obstruction of the small bowel. METHODS: Twenty-five patients with surgically confirmed closed loop and strangulating obstruction were divided into two groups with (n = 16) and without (n = 9) intestinal necrosis. By using univariate and multivariate statistical procedures, we evaluated the differences in CT findings between the two groups on the basis of the following six findings: bowel dilatation of strangulated loops (bowel dilatation), wall thickening of strangulated intestines (wall thickening), ascites, vascular dilatation of affected mesenteries (vascular dilatation), elevation of mesenteric attenuation (mesenteric attenuation), and radial distribution of the mesenteric vessels (radial distribution). RESULTS: Of the six findings, ascites, vascular dilatation, mesenteric attenuation, and radial distribution provided significant discriminating findings between the two groups on univariate analysis. On multivariate analysis, mesenteric attenuation was the most important discriminative factor, followed by radial distribution and ascites. Using these three parameters, the CT was correlated with the surgical findings in 15 of the 16 patients in the necrosis group (sensitivity = 93.8%) and in eight of the nine patients in the nonnecrosis group (specificity = 88.9%). The overall accuracy was 92.0%. CONCLUSIONS: Mesenteric attenuation, radial distribution, and ascites, depicted on CT differentiate well between necrosis and nonnecrosis of the small bowel in patients with closed loop and strangulating obstruction.

Case-Control Studies↗
PubMed1994

Tumor microvessel density, p53 expression, tumor size, and peritumoral lymphatic vessel invasion are relevant prognostic markers in node-negative breast carcinoma.

PURPOSE: To determine the absolute and relative value of microvessel density (MVD), p53 and c-erbB-2 protein expression, peritumoral lymphatic vessel invasion (PLVI), and conventional prognosticators in predicting relapse-free (RFS) and overall survival (OS) rates in patients with node-negative breast carcinoma (NNBC). PATIENTS AND METHODS: We monitored 254 consecutive patients with NNBC for a median of 62 months. Intratumoral MVD was measured after microvessels were immunostained using anti-CD31 antibody. p53 and c-erbB-2 protein and hormone receptors were also determined immunocytochemically. Results were analyzed by both univariate and multivariate statistical analysis. RESULTS: Univariate analysis showed that MVD was significantly predictive of both RFS (odds ratio [OR], 8.30; P = .0001) and OS (OR, 4.50; P = .012) when tested as a continuous or dichotomous variable. Likewise, tumor size (OR, 3.16; P = .0012), PLVI (OR, 4.36; P = .0009), estrogen receptor (ER) status (OR, 2.35; P = .016), progesterone receptor (PR) status (OR, 2.00; P = .017), and expression of p53 protein (OR, 2.82; P = .004) were significantly associated with RFS. Tumor size (OR, 3.80; P = .0038) and expression of p53 protein (OR, 2.58; P = .024) were significantly associated with OS by univariate analysis. Multivariate analysis showed that MVD (P = .0004), p53 protein expression (P = .0063), tumor size (P = .0144), and PLVI (P = .0033) were all significant and independent prognostic factors for RFS. However, only tumor size (P = .004) and MVD (P = .047) were independent predictors for OS. c-erbB2 expression was not associated with outcome by either univariate or multivariate analysis. CONCLUSION: MVD, p53 expression, PLVI, and tumor size are independent prognostic indicators of recurrence, which are useful in selection of high-risk NNBC patients who may be eligible to receive adjuvant therapies.

Adult↗
PubMed1997

Heart surgery in patients aged eighty years and above: determinants of morbidity and mortality.

Escalating medical costs, limitation of resources and the necessity to provide cost-effective medical care have created a need for systematic risk stratification and cost-benefit analyses in the background of an ongoing discussion. Results of heart surgery in octogenarians have been evaluated in a prospective single-center, study since 1990. 101 consecutive patients (55/ 101 = 54.5% female) aged 80 years and above (median: 81 years; interquartile range [IQR]: 80.0-82.5, total range [TR]: 80-92 years) undergoing open heart surgery at our institution between January 1990 and March 1996 were included into this prospective study. Prior to surgery, most patients were severely symptomatic being in functional NYHA classes either III (56.4%) or IV (31.7%). 61/101 (60.4%) patients underwent isolated coronary artery bypass grafting (CABG), 23 (22.8%) had aortic valve replacement (AVR), 14 patients (13.9%) had CABG combined with AVR or double valve replacement and 3 (3.0%) had mitral valve repair. Follow-up (median: 23.0 months. IQR: 10.5-39.0, TR: 1-72) was focused on long-term morbidity and quality of life. The impact of preoperative and operative risk factors on morbidity and mortality was determined by uni- and multivariate statistical analysis. The 30-days overall mortality in this study was 7.9%. The postoperative course was uneventful for 27 (26.7%) of our patients. Univariate risk factors of postoperative mortality were: left main stem disease (p < or = 0.044), ejection fraction < 45% (p < or = 0.006), preoperative intensive care unit (ICU) (p < or = 0.002), urgent or emergency operation (p < or = 0.034). The only independent predictor of operative mortality was preoperative ICU-stay (p < or = 0.008). Significant risk factors for the number of postoperative complications in the multivariate analysis were: prior stroke (p < or = 0.04), diabetes mellitus (p < or = 0.02), New York Heart Association (NYHA) class IV symptoms (p < or = 0.002) and prolonged cross-clamping time (p < or = 0.001). Mean postoperative length of stay in the ICU was 3.9 +/- 3.9 days. Late morbidity was not related to postoperative complications. Cumulative survival was 87.9%, 79.5% and 72.9% at one, two or five years, respectively. After hospital discharge, 67/93 patients (82.8%) were in NYHA functional class I or II. Cardiac surgery in very elderly patients can be performed with acceptable operative risk and a favorable long-term outcome. The individual patient risk-profile including significant co-morbid conditions and severity of the heart disease predicts not only survival but the extent of perioperative morbidity.

Aged↗
PubMed2004

The effect of smoking on outcome following external radiation for localized prostate cancer.

PURPOSE: We investigated whether a smoking habit affects biochemical and survival outcome after curative external beam radiation therapy (EBRT) for localized prostate cancer. MATERIALS AND METHODS: The study population comprised 601 men treated with curative EBRT between 1994 and 1997 who had a smoking history available. Pretreatment prognostic factors were examined and high risk was defined as any of prostate specific antigen greater than 20, Gleason greater than 7 or stages T3-4. Biochemical outcome (bNED) was assessed by American Society for Therapeutic Radiology and Oncology, and Houston criteria. Biochemical, clinical, prostate cancer and nonprostate cancer death rates were examined by univariate and multivariate statistics. RESULTS: Of the men 15% were current smokers, 55% were former smokers and 31% were nonsmokers. Current smokers were younger than former smokers or nonsmokers by a mean of 2.5 years (p <0.001). Current smokers had higher risk cancers than former smokers or nonsmokers (high risk 60%, 40% and 43%, respectively, p = 0.017). Five-year bNED rates for smokers were significantly worse than for former smokers or nonsmokers (55%, 69% and 73%, p = 0.01 and 0.0019, respectively). Median followup was 59 months. Multivariate analysis confirmed smoking as an independent adverse factor for bNED (p = 0.013) even when controlling for prostate specific antigen (p <0.0001), Gleason score (p <0.0001), stage (not significant), radiation dose (not significant) and neoadjuvant hormone use (p = 0.0014). Local and metastatic failure did not differ among the groups. Prostate cancer specific mortality was nonsignificantly worse in smokers but overall mortality was much greater. CONCLUSIONS: Smokers present with higher risk prostate cancers. Outcomes following EBRT are poorer, even when accounting for differences in known pretreatment factors.

Aged↗
PubMed1999

Preoperative p53, bcl-2, CD44 and E-cadherin immunohistochemistry as predictors of biochemical relapse after radical prostatectomy.

PURPOSE: Since radical prostatectomy is performed to cure prostate cancer, identification of markers enabling preoperative prediction of relapse after radical prostatectomy is essential to counsel and select patients for adjuvant therapy. Aberrant p53, bcl-2, CD44 and E-cadherin immunohistochemistry has been associated with aggressiveness in prostate cancer. We assessed these biomarkers in biopsy and radical prostatectomy specimens as predictors of biochemical relapse. MATERIALS AND METHODS: A total of 76 patients with untreated clinically localized prostatic adenocarcinoma underwent radical prostatectomy. Preoperative (prostate specific antigen, biopsy Gleason score) and postoperative (pathological stage and margin status) variables, biopsy and radical prostatectomy biomarker immunohistochemistry were correlated with relapse. Univariate and multivariate statistical analyses identified significant predictors. RESULTS: Of the 76 patients 23 (30%) had relapse (mean followup 38 months). Aberrant p53, bcl-2, CD44 and E-cadherin expression was observed in 64, 12, 85 and 12% of biopsies and 57, 20, 64 and 49% of radical prostatectomy specimens, respectively. Biopsy Gleason 7 to 10 and biopsy p53, respectively, gave the highest positive and negative predictive values for relapse. Relapse occurred in 13% of patients with normal biopsy p53 and in half with aberrant p53. Multivariate analysis revealed Gleason score and p53 to be independent preoperative predictors (p = 0.01 and 0.02, respectively). Estimated risk of relapse was 3.5 times higher in patients with Gleason scores 7 to 10 and 24% higher in those with aberrant p53. Significant postoperative predictors were bcl-2, p53, Gleason score and margin status (p = 0.01, 0.01, 0.04 and 0.01, respectively). CONCLUSIONS: Aberrant biopsy p53 is associated with a significantly worse outcome after radical prostatectomy than normal p53, highlighting a potential clinical role for p53. Postoperative p53 and bcl-2 were significant predictors of outcome after radical prostatectomy.

Aged↗
PubMed1995

Risk factors for operative morbidity in patients with systemic lupus erythematosus: an analysis of 63 surgical procedures.

The surgical morbidity rate of patients with Systemic Lupus Erythematosus is considered very high; however, the experience in the literature is small. This study will determine the rate of surgical morbidity and the existence of predictive factors in patients with such a disease. The medical records of 53 patients with Systemic Lupus Erythematosus who underwent 63 major operations were analyzed retrospectively. The rate and causes of operative morbidity were registered. Univariate and multivariate statistical analysis was performed to ascertain the existence of predictive factors for morbidity. The overall morbidity and mortality were 16% and 6% respectively. Lymphopenia, hypoalbuminemia, increased SGOT and SGPT, urgent indication of operation, the physical status of the American Society of Anesthesiology, as well as a shorter duration of Systemic Lupus Erythematosus showed a significant correlation with operative morbidity in the univariate analysis; high blood urea nitrogen showed marginal significance. Physical status, urgent indication, and blood urea nitrogen remained as significant variables with the multivariate logistic regression analysis. The surgical morbidity rate of these patients may be lower than previously estimated. The physical status, urgency of operation, and level of blood urea nitrogen seemed to be the most useful independent predictors for surgical morbidity risk in patients with Systemic Lupus Erythematosus.

Adult↗
PubMed1989

Famotidine therapy for active duodenal ulcers. A multivariate analysis of factors affecting early healing.

OBJECTIVE: To identify factors that influence the rate of healing of duodenal ulcers. DESIGN: A stepwise multivariable statistical analysis of patients with duodenal ulcer in a multicenter, prospective, open-label study. Healing was assessed by endoscopy at 4 or 8 weeks. Antacid use and symptoms were recorded in a daily diary. SUBJECTS: Of 135 patients, ages 19 to 86, 50% had a previous duodenal ulcer, 46.7% smoked, and 34.8% had melena or hematemesis. INTERVENTIONS: Famotidine, 40 mg orally, at bedtime for 4 or 8 weeks depending on endoscopic evaluation of ulcer healing. Limited antacid use was permitted. SETTING: Office practices, hospital practices, and university-based medical centers. MEASUREMENTS AND MAIN RESULTS: Multivariable analysis identified five independent predictors present at the time of diagnosis that influenced ulcer healing. The odds of not healing for each risk factor after simultaneous adjustment of the other risk factors were as follows: alcohol use, 6.5 (CI, 2.0 to 20.7, P less than 0.002); ulcer size greater than 10 mm, 4.2 (CI, 1.5 to 11.6, P less than 0.005), bleeding symptoms. 3.5 (CI, 1.2 to 10.2, P less than 0.03); and a previous duodenal ulcer, 3.1 (CI, 1.05 to 9.0, P less than 0.04). The use of salicylates or nonsteroidal anti-inflammatory drugs before treatment was associated with an improved odds of healing (adjusted odds ratio, 0.2; CI, 0.1 to 0.9, P less than 0.04). The percentage of patients achieving complete ulcer healing after 4 weeks of famotidine decreased inversely with the number of risk factors present, ulcer size, and the quantity of daily alcohol use (P less than 0.001). Fewer than half of those patients who still had severe pain at day 7 achieved healing at 4 weeks (P less than 0.001). In contrast, smoking and 23 other factors had no statistically discernible effect on ulcer healing with famotidine. CONCLUSIONS: Five variables present at the time of diagnosis independently influenced the rate of ulcer healing at 4 weeks: alcohol use, ulcer size, bleeding symptoms, a previous duodenal ulcer, and previous use of salicylates or nonsteroidal anti-inflammatory drugs.

Adult↗
PubMed1996

P53 overexpression in head and neck carcinoma and radiotherapy results.

PURPOSE: P53 gene mutations are the common genetic changes encountered in human cancers, and there is extensive evidence that the P53 status may determine tumor response to therapy. This study was carried out to investigate whether there is any correlation between accumulation (overexpression) of P53 protein and poor prognosis in patients with head and neck carcinomas treated with radical radiotherapy. METHODS AND MATERIALS: Seventy-nine patients with head and neck carcinomas who were diagnosed and treated in 1989-90 with curative radiotherapy were studied retrospectively. Paraffin sections from archival material were studied using immunohistochemical staining (IHC) with mouse monoclonal antibodies (D0-7) to human P53 protein. Univariate and multivariate analysis of loco-regional tumor control and patient survival were performed on possible prognostic factors. RESULTS: Forty-two (53%) patients showed positive IHC staining in their tumors. Fifty-three percent of the laryngeal, 64% of the oropharyngeal, and 43% of the oral cavity carcinomas showed P53 overexpression. All tumor specimens with vascular, lymphatic, and/or sarcolemmal invasion showed P53 overexpression. The proportion of tumor-stained nuclei was higher in the poorly differentiated than in the well and moderately differentiated tumors (p < 0.05), but there was no correlation with the patient overall or disease-free 5-year actuarial survival. There was no difference in the 5-year actuarial survival and disease-free survival between patients with P53 immunostaining in their tumors and those with no immunostaining (59% vs. 65% and 57% vs. 51%, respectively). The TNM tumor stage was the most significant prognostic factor with 5-year actuarial survival of 87% for early and 14% for late stages (p << 0.0001). There was a significant correlation between immunostaining and history of smoking (p = 0.02). CONCLUSION: The data demonstrate that the P53 accumulation as detected by immunohistochemical staining in a group of head and neck carcinomas was not predictive of patient's poor survival or disease-free survival. Multivariate statistical analysis showed that the TNM tumor stage was the only significant prognostic factor. There was a significant association between P53 accumulation and smoking.

Adult↗
PubMed1987

[A new model for the study of filarial physiopathology: Molinema dessetae in its definitive natural host, Proechimys oris. 1].

The filarial rodent model Molinema dessetae/Proechimys oris, recently adapted in the laboratory allows studies on the host/parasite relationships. Development of filarial worm was described elsewhere, and the model standardized. Biological, parasitological data and antifilarial drug response were determined. Natural models can seldom be used in laboratory; in non natural models many informations on the host-parasite relationships are lost and pathological studies can only be fragmentary and punctual. With inbred Proechimys oris we have the possibility to investigate with a natural filarial model. Three rodent groups have been studied for over a period of one year. The first group comprises eleven parasite free animals; the second one, eight rodents infected once by L3, and the last with eight rodents regularly re-infected during the period of experiment. Several biological parameters were considered: weight, total red and white blood cell counts, haemoglobinemia, mean cell volume, differential leucocyte count, blood urea nitrogen, total serum proteins and electrophoretic pattern, endogenous creatinine clearance, circulating immune complexes. On the whole, more than 19,700 biological data were obtained and several multivariate statistical analysis were necessary for a valid interpretation. The Principal Component Analysis (ACP) shows in each infected rodent distinct trajectories related either with the age of the host or with the filarial infection itself. Three graphic methods were used: individual graphics of each rodent, graphics of each rodent group and, individual and group statistical center of gravity. At the end of the experiments, the rodents were autopsied and a detailed histological study of the whole body was made. Different lesions and stages of inflammatory processes found were analysed and classified as follows: granulomatous nodule with eosinophilic and neutrophilic polymorphs; foreign-body granulomatous nodule; sclerocicatricial nodule; mononucleate cell infiltrate. Secondary pathological alterations, such as irritative lesions and blocage of lymph and blood vessels, were found. A comprehensive study of all our qualitative histological results was performed by a second multivariate analysis: the Correspondence Analysis (AFC). This analysis confirmed the heterogeneity of each Proechimys infected and multi-infected groups. The cross checking between the ACP and AFC allows the separation of two physiopathological filarial groups; the first group (A) is characterized by moderate biological variations and the absence of hepatosplenic lesions.(ABSTRACT TRUNCATED AT 400 WORDS)

Aedes↗
PubMed1991

Prognostic significance of image cytometry DNA parameters in tissue sections from breast and gastric cancers.

The ploidy patterns determined for several groups of mammary and gastric carcinomas were subjected to a set of statistical analyses. The DNA distribution patterns were derived from image cytometry measurements of each of at least 150 Feulgen-stained tumour cell nuclei from tissue sections from 84 invasive ductal carcinomas of the breast and from 30 tubular adenocarcinomas of the stomach. Widely used DNA parameters (mean value, standard error of the mean, DNA-malignancy grade, 2c deviation index and the exceeding rate according to Böcking, DNA-histogram types according to Auer, DNA-index according to Atkin) were analysed by univariate and multivariate statistics. The DNA histograms were also analysed multiparametrically. The results showed different prognostic groups of the breast tumours to be distinguishable on single parameters with a reliability of up to 66%. None of these parameters permitted the discrimination of gastric carcinomas. Although the DNA-histogram-analysis increased accuracy by nearly 10%, compared with the classification accuracy of the best single parameters, it is still far from being applicable in clinical diagnostics. The use of further image cytometry parameters will be required for such applications.

Adenocarcinoma↗
PubMed2005

[Use of blood products in patients treated surgically for stage I non-small cell lung cancer].

OBJECTIVE: Retrospective study on the relation between the use of blood products and survival rates in patients treated surgically for stage I non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: The study included 856 patients who underwent surgical resection from 1969 to 2000 for stage I NSCLC, classified histologically according to the current guidelines of the Spanish Society of Pulmonary and Thoracic Surgery (SEPAR). Patients who died in the postoperative period were excluded from the study. A series of clinicopathological variables were recorded, including the perioperative use or not of blood products. Descriptive, univariate, and multivariate statistical analyses were performed. Follow up concluded in December of 2003. RESULTS: One hundred twenty-five patients (14.6%) underwent a perioperative transfusion. A significant association was found between the use of blood products and tumor size (P<.001), pneumectomy (P<.001), and cell type (P<.05). The respective 2, 5, and 10-year survival rates were 78%, 63%, and 54% for the nontransfusion group, and 73%, 59%, and 46% for the transfusion group. Both survival curves were compared and no significant differences were found (P=.23). Multivariate regression analysis included tumor size, patient age, and histologic cell type (squamous cell carcinoma or not); no relation between transfusion and survival was found. CONCLUSIONS: In our series, we found no difference in survival rates for patients with stage I NSCLC after perioperative blood transfusion.

Aged↗
PubMed1997

Proliferating cell nuclear antigen and heat shock protein 70 immunolocalization in invasive ductal breast cancer not otherwise specified.

A series of 80 female patients undergoing surgery for primary breast ductal infiltrating carcinoma not otherwise specified (NOS) was immunohistochemically studied in order to verify any relationships between Proliferating Cell Nuclear Antigen (PCNA) immunostaining, Heat Shock Protein 70 (HSP70) immunoreactivity, and several clinicopathological predictors. Positive PCNA scores (> 20% of strongly immunopositive malignant nuclei) were observed in neoplastic cells' nuclei in 13 tumors (16.25%) and were intimately associated with axillary nodal involvement (p = 0.0131), relatively high tumor grades (p = 0.0016), increased tumor size (p = 0.0312), and low or negative levels of estrogen receptors (p = 0.0323). HSP70 positive immunoexpression in malignant cells' cytoplasm (percentage of HSP70 immunoreactive cells > 10%) was detected in 33 samples (41.25%). It correlated significantly with presence of axillary lymph nodal metastases (p = 0.0033) and rather poor tumor differentiation (p = 0.0014), whereas an association of borderline statistical significance emerged between HSP70 immunoreactivity and high progesterone receptor status (p = 0.0637). PCNA positive immunostaining demonstrates the tumors' proliferative fraction and might be used as an indicator of increased malignant potential in breast cancer since it was associated with four adverse prognosticators. HSP70 immunodetection is a probable marker of the biological stress experienced by breast cancer cells, since it was related to relatively high tumor grades. Since both proteins may potentially predict disease outcome, their prognostic significance must be validated by direct relation to survival. A multivariate statistical analysis including the variables with which both proteins were associated will reveal any possible independent prognostic value of PCNA and HSP70 immunostaining in local, ductal invasive breast cancer NOS.

Adult↗
PubMed2001

The prevention of haematoma following rhytidectomy: a review of 1078 consecutive facelifts.

Haematoma remains the most common complication of rhytidectomy and can lead to prolonged facial oedema or skin necrosis. The factors leading to haematoma formation remain unclear, and studies establishing causal relationships are lacking. The aim of this study was to determine which parameters were significantly associated with haematoma formation in a consecutive series of facelifts performed by two high-volume operators. The records of 1078 patients who underwent facelifting between 1994 and 1999 were reviewed and the parameters associated with haematoma formation were investigated using multivariate statistical analysis. In this series of 1078 patients, 45 haematomas occurred (4.2%). Analysis revealed significant associations between haematoma formation and anterior platysmaplasty (P= 0.009), systolic pressure (P= 0.02), gender (P= 0.03), aspirin or non-steroidal anti-inflammatory intake (P= 0.04) and smoking (P= 0.049). In addition the relative risk of each parameter was calculated. This allowed the haematoma risk for individual patients to be calculated and haematoma-prone patients were identified preoperatively. This is the first study to establish independent statistical risk factors for haematoma after rhytidectomy and to present a scoring system that calculates the haematoma risk preoperatively. The implications of these findings and possible measures for the prevention of haematoma are also presented.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMedDate not supplied

Changes in crestal bone levels for immediately loaded implants.

PURPOSE: The authors' objective was to measure crestal bone level change in subjects with immediately loaded implants and to identify risk factors associated with changes in bone level. MATERIALS AND METHODS: A retrospective cohort study design was used. The sample comprised subjects who had had endosseous implants placed and immediately loaded between July 2001 and July 2003. Demographic, health status-related, anatomic, implant-specific, prosthetic, and surgical variables were examined. The primary outcome variable was change in crestal bone level over time. Appropriate uni-, bi-, and multivariate statistics were computed. RESULTS: The sample comprised 174 subjects who received 347 immediately loaded implants. The mean duration of radiographic follow-up was 6.9 +/- 4.0 months, respectively. Mean changes in radiographic bone level were -0.5 mm and -0.6 mm on the mesial and distal surfaces, respectively, after a mean of 6.9 months of radiographic follow-up. Using least squares methods, it was estimated that radiographic bone levels would be -1.0 mm and -0.8 mm on the mesial and distal surfaces, respectively, at 12 months. The multivariate model revealed that radiolucency at or adjacent to implant site was associated with an increased risk of crestal bone loss (odds ratio, 1.88; 95% CI, 1.00 to 3.60). Twelve months after placement, 92.5% of implants had had < or = 1.5 mm of crestal bone loss. DISCUSSION: The results of this study were comparable to the results of other studies comparing immediate loading to delayed loading. Further research to estimate long-term changes in crestal bone loss and to identify risk factors for bone loss with immediate loading is recommended. CONCLUSION: This study suggests that crestal bone level changes with immediately loaded implants were within the recommended range for 92.5% of the evaluated implants. The mandible showed a higher risk for crestal bone loss compared to the maxilla.

Adolescent↗
PubMed1988

Blood lead and associated risk factors in Ontario children.

The purpose of this study was to determine blood levels in Ontario children and to identify those risk factors associated with higher blood lead levels. A random sample of 1315 children aged 7 and younger from urban, suburban and rural Ontario was selected. Blood lead concentration was determined in finger prick blood samples by graphite furnace atomic absorption spectrophotometry. Measurements of lead in air, tap water, soil, and gasoline were also established. Traffic pattern were determined in each area. A questionnaire was administered to a random sample of 800 families of the children tested to assess the presence of other risk factors. Urban children had higher geometric mean blood lead levels (12.02, S.D. = 4.4 micrograms/dl) than suburban children (9.95, S.D. = 3.5 micrograms/dl), and they, in turn, had higher blood lead levels than rural children (8.91, S.D. = 3.9 micrograms/dl). Each of these differences is statistically significant (p less than 0.001). Fifty four (4.3%) of all children were at or above the alert level of 20 micrograms/dl. The proportion above the alert level did not differ significantly between urban, suburban and rural children. Blood lead levels were slightly higher for males than females and for pre-schoolers aged 3 and 4, compared to school age children aged 5 and 6. The blood lead levels of these children were significantly lower than that of children surveyed near a point source of industrial emissions. Multivariate statistical modelling resulted in a set of characteristics which best explained the differences in children's blood lead levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed2002

Acylglycerol and fatty acid components of pulp, seed, and whole olive fruit oils. Their use to characterize fruit variety by chemometrics.

The contents of triacylglycerols and diacylglycerols in three kinds of olive fruit oils (pulp, seed, and whole fruit) were determined. The fatty acid composition and the quality ratios 1,2-diacylglycerols/1,3-diacylglycerols and 1,2-diacylglycerols/total diacylglycerols were also assessed. Seven major Italian olive varieties were considered. Results of univariate statistical analyses indicated that the above analytical parameters (glyceridic ratios excepted) were effective in discriminating between pulp and seed oils. The seed oil fraction did not determine any change in the glyceridic indices and the acylglycerol or fatty acid composition concerning the whole fruit oil (mixture of pulp and seed oil fractions), the weight (%) of seed ( approximately 2%) being by far lower than the weight (%) of pulp ( approximately 85%) (fruit weight basis). Based on the data of triacylglycerol or fatty acid composition, and using appropriate parametric or nonparametric multivariate statistics, the genetic origins (olive variety) of the three fruit oil kinds were characterized.

Diglycerides↗
PubMed1986

Clinical significance of supraventricular tachyarrhythmias after acute myocardial infarction.

160 survivors of acute myocardial infarction (AMI) were evaluated to assess the clinical significance of supraventricular tachyarrhythmias (SVTA) occurring at discharge from the hospital after the acute event. All the variables considered for the study were estimated before hospital discharge; arrhythmias were quantified with a 24 h Holter ECG monitoring system. SVTA occurred in 88 patients (55%). Single or repetitive supraventricular premature beats were found in 65 (41%), paroxysmal atrial or junctional tachycardias in 20 (12%), bouts of atrial flutter or fibrillation in 3 (2%). Bivariate statistical analysis showed no relationship between sex, previous cardiovascular history, type, and location of AMI and SVTA occurrence. A close positive relationship was found between age, left atrial dimension (LAD), cardio-thoracic ratio (CTR) and SVTA occurrence; an inverse relationship was found for left ventricular ejection fraction (LVEF). The presence of SVTA appeared significantly related to age above 55 years, to LAD greater than 40 mm, to LVEF less than 45%, to serum creatine kinase peak levels over 1400 U l-1 and to CTR over 0.49. Multivariate statistical analysis showed that five variables are important in discriminating patients suffering from SVTA: age, LAD, LVEF, left ventricular fractional shortening, and CTR. SVTA occurring at discharge from hospital after AMI are indicative of impaired left ventricular pump function.

Analysis of Variance↗
PubMed2001

Factors associated with low bone mineral density in female patients with systemic lupus erythematosus.

OBJECTIVE: To study risk factors for low bone mineral density (BMD, g/cm) in patients with systemic lupus erythematosus (SLE). METHODS: Ninety-two consecutive patients with SLE followed by rheumatology faculty between 1997 and 1999 completed a questionnaire regarding lifestyle during the clinic visit, a chart review was performed, and data were collected for the time of the first dual energy x-ray absorptiometry (DXA) examination. Univariate and multivariate statistical analyses were used to assess relationships between various risk factors and BMD. RESULTS: Ninety-eight percent of patients had received prednisone, 51% were postmenopausal (9 of whom received hormone replacement therapy), 68% had received hydroxychloroquine, and 15% were osteoporotic. The following factors were found to be significantly related to lower BMD by univariate analysis: Caucasian race, older age at diagnosis, higher age at the time of the first DXA, longer disease duration, higher cumulative corticosteroid dose, higher SLE Damage Index score, and postmenopausal status. In the multivariate analysis only the following factors were significant: Caucasian race, increased number of pregnancies, postmenopausal status, higher SLE Damage Index, and higher cumulative corticosteroid dose. An unexpected finding was that taking hydroxychloroquine was the only factor associated with higher BMD of the hip and spine in the univariate analysis, and it remained predictive of higher BMD of the hip and spine in the multivariate analysis. CONCLUSION: Hydroxychloroquine appears to protect against low BMD in corticosteroid treated patients with SLE.

Absorptiometry, Photon↗