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2.
Appl Microbiol Biotechnol ; 63(4): 460-5, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14716469

ABSTRACT

Biodegradation of organic contaminants in multi-phase systems, such as soils and aquifers, is often limited by the extent and the rate of contaminant sorption onto the solid matrix. However, information about biodegradation in complex matrices is largely limited to studies of closed systems under batch conditions in which potential bioavailability is characterised by the aqueous-phase concentration of a contaminant. There is little knowledge regarding the influence of flow-through conditions on the availability of contaminants to microbes (contaminant bioavailability). Thus, the aim of this study was to assess and compare contaminant bioavailability, in the presence of a sorptive medium, under both batch and flow-through conditions. Accordingly, experiments were designed in which pentachlorophenol (PCP) was introduced into a mixture of inoculated silica sand and a PCP-retaining resin, under either batch or flow-through (columns) conditions. The results indicated that an increase in the amount of resin (0.1-0.2 g) clearly lowered PCP availability to microbes after 170 h under batch conditions (30 and 45% respectively); whereas, the initial decrease in bioavailability observed under flow-through conditions (45 and 70% respectively) was reversed and no longer observable after 170 h. This increase in PCP availability was linked to an improvement in the contaminant biodegradation capacity from 0.03 to 0.13 mg x l(-1) x h(-1) over 200 h.


Subject(s)
Bacteria/growth & development , Bacteria/metabolism , Pentachlorophenol/metabolism , Adsorption , Biodegradation, Environmental , Biological Availability , Kinetics , Resins, Synthetic/chemistry , Sphingomonas/growth & development , Sphingomonas/metabolism , Water Pollutants, Chemical/metabolism
3.
J Clin Microbiol ; 41(11): 5207-8, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14605164

ABSTRACT

We conducted a seroepidemiologic study to determine the prevalence of anti-human herpesvirus 8 antibodies in a renal transplant population at Hôtel-Dieu de Québec Hospital. Testing for immunoglobulin G antibodies against lytic and latent antigens was performed on serum samples from 150 renal transplant patients. Human immunodeficiency virus-positive patients with confirmed Kaposi's sarcoma were used as positive controls. None of the renal transplant patients tested positive.


Subject(s)
Antibodies, Viral/blood , Herpesviridae Infections/epidemiology , Herpesvirus 8, Human/immunology , Kidney Transplantation/adverse effects , Sarcoma, Kaposi/epidemiology , Antigens, Viral/analysis , HIV Seropositivity/epidemiology , Herpesviridae Infections/immunology , Herpesvirus 8, Human/classification , Herpesvirus 8, Human/isolation & purification , Humans , Postoperative Complications/virology , Quebec/epidemiology , Sarcoma, Kaposi/immunology , Seroepidemiologic Studies , Time Factors
4.
Appl Microbiol Biotechnol ; 58(3): 409-15, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11935195

ABSTRACT

Biological removal by indigenous microflora of cyanide, contained in old (6-9 years) and fresh tailings (3 months), was studied in order to assess its natural attenuation potential via biodegradation. To investigate the presence of indigenous microflora in tailings, total heterotrophic and cyanide resistant bacteria were counted using the spread-plate method. The free cyanide mineralization potential was estimated using K14CN in the presence of various unlabeled cyanide concentrations (0, 5, and 10 mg CN/kg). The biodegradation of cyanide contained initially in the samples was also investigated by monitoring formate, formamide, ammonia and total cyanide (CNT) concentrations over 111 days. The enumeration of total heterotrophic and cyanide-resistant bacteria in old tailings showed an average population of 105 cfu/g. However, no growth was detected in fresh tailings. Nevertheless, cyanide mineralization tests indicated the presence, in both old and fresh tailings, of a cyanide-degrading microflora. In old tailings, maximum mineralization percentages of free cyanide ranging from 85% to 100% were obtained after 65 days at all concentrations tested. A mineralization percentage of 83% after 170 days was also observed in fresh tailings. No decrease of total cyanide concentration in old tailings was observed when the biodegradation of endogenous cyanide was tested whereas a significant decrease was recorded in fresh tailings after 96 days. The presence of strong metal-cyanide complexes resistant to biodegradation could explain the absence of biodegradation in old tailings. This study demonstrated the presence of an indigenous free cyanide-degrading microflora in both old and fresh tailings, and suggests that natural attenuation of cyanide in gold mine tailings is likely to occur via microbial activity.


Subject(s)
Bacteria/metabolism , Cyanides/metabolism , Gold , Mining , Biodegradation, Environmental , Colony Count, Microbial/methods , Cyanides/analysis , Geologic Sediments/analysis , Gold/chemistry , Hydrogen-Ion Concentration , Industrial Waste , Minerals/metabolism , Soil/analysis , Soil Microbiology
5.
Food Addit Contam ; 18(8): 739-49, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11469330

ABSTRACT

Thermal desorption, followed by gas chromatography (GC) with mass spectrometry (MS) detection, has been found to allow the rapid identification of volatile products resulting from the gamma-irradiation of stabilized, high density polyethylene packaging and pure stabilizers. The stabilizers were tris(2,4-di-tert.butylphenyl) phosphite, octadecyl beta-(2,6-di-tert.butylphenol)-propionate and 2,4-di-tert.butylphenol, the latter resulting from phosphite hydrolysis. Thermal desorption indicated the formation and release of tert.butylbenzenes, such as 1,3-di-tert.butylbenzene upon gamma-irradiation of the HDPE. From a comparison of the products from gamma-irradiation of additive-free polyethylene, of various pure stabilizers and of related compounds, the tert.butylbenzenes were confirmed to result from the irradiation of the phosphite stabilizer and its phosphate conversion product. Thermal desorption off-line, in which volatiles released by a sample are trapped in sorbents for subsequent desorption in the heated GC inlet, is found to be a fast, extremely sensitive method that can be used to guide and supplement analyses of compounds extracted by foodstuffs.


Subject(s)
Excipients/radiation effects , Food Packaging , Polyethylene/radiation effects , Chromatography, Gas , Humans , Mass Spectrometry , Sensitivity and Specificity , Volatilization/radiation effects
6.
Food Addit Contam ; 18(6): 581-91, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11407757

ABSTRACT

Infrared (IR) spectroscopy has been used to identify and quantify the phosphite antioxidant, tris(2,4-di-tert.butylphenyl) phosphite, and its corresponding phosphate in high density polyethylene (HDPE) food trays, both in the original, commercial trays and also as a function of gamma-irradiation and post-irradiation, storage conditions. This direct method of inhibitor analysis complements time-consuming (some times non-quantitative) extraction methods, which for organo-phosphites are complicated by their facile conversion to phosphates by peroxidic impurities in the solvent. Because of the complete destruction of phosphite to give mainly phosphate at quite low gamma-irradiation doses (approximately 5 kGy) and phosphate formation during melt processing and radiation sterilization of these HDPE trays must take into account products from the irradiation of phosphate. Any residual phosphite is lost progressively in post-irradiation reactions, which are complex, producing a less than-quantitative yield of phosphate.


Subject(s)
Food Irradiation , Food Packaging , Gamma Rays , Phosphites/radiation effects , Polyethylene , Chromatography, High Pressure Liquid , Humans , Phosphites/chemistry , Spectroscopy, Fourier Transform Infrared/methods
7.
Water Res ; 35(8): 2029-37, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11337851

ABSTRACT

Biological clogging is promoted in aquifers either to contain or to remediate groundwater. In this study, an apparatus able to detect small changes in hydraulic conductivity (K) was developed to measure the clogging of a single fracture in limestone, following microbial stimulation. The fracture had a 2.5 mm2 section and was 50 cm long. Prior to the inoculation of the limestone, the sequencing of representative clones from 16S rRNA genes isolated from groundwater, showed significant affiliation with Cytophaga spp., Arcobacter spp. and Rhizobium spp. These bacteria are known to secrete extracellular polymeric substances and form biofilms. When nutrients were added to the inoculated limestone, a decrease in K occurred after 8 days, reaching 0.8% of its initial value after 22 days (Kfi = 340 cm min-1). This study showed that a stimulation of indigenous microbes from groundwater effectively clogged a macrofracture in limestone, suggesting the potential application of biobarriers in fractured rock aquifers.


Subject(s)
Arcobacter/isolation & purification , Calcium Carbonate , Cytophaga/isolation & purification , Rhizobium/isolation & purification , Water Microbiology , Water Pollution/prevention & control , Water Purification/methods , Arcobacter/classification , Arcobacter/genetics , Biofilms , Cytophaga/classification , Cytophaga/genetics , DNA, Ribosomal/genetics , DNA, Ribosomal/isolation & purification , Equipment Design , Phylogeny , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 16S/isolation & purification , Rhizobium/classification , Rhizobium/genetics , Water Purification/instrumentation
8.
Science ; 292(5515): 255-8, 2001 Apr 13.
Article in English | MEDLINE | ID: mdl-11303094

ABSTRACT

Single-molecule spectroscopy was used to follow the orientation of a single probe molecule in a polymer film in real time. Broad spatially heterogeneous dynamics were observed on long time scales, which result from simple diffusive rotational motions on short time scales. This diffusive behavior persists for many rotations before the molecule's local environment changes to one characterized by a new time scale. This environmental exchange occurs instantaneously on the time scale of the experiment and may arise from large-scale collective motions. The distribution of exchange times for these environments was measured for several temperatures near the glass transition.

9.
Microb Ecol ; 42(1): 56-68, 2001 Jul.
Article in English | MEDLINE | ID: mdl-12035081

ABSTRACT

The stimulation of groundwater bacteria to form biofilms, for the remediation of polluted aquifers, is subjected to environmental regulations that include measurement of effects on microbial biodiversity. Groundwater microorganisms contain a proportion of unidentified and uncharacterized ultramicrobacteria (UMB) that might play a major role in the bioclogging of geological materials. This study aimed to assess the changes in genetic and metabolic biodiversity when a community of UMB, isolated from groundwater, is stimulated to form biofilms on a ceramic surface. UMB were stimulated with aerobic conditions and injection of molasses, in reactors reproducing groundwater composition and temperature. Concentration of planktonic viable UMB, secretion of extracellular polymeric substances (EPS), and biofilm thickness were monitored. The assessment of changes in biodiversity was achieved by comparing the initial UMB community to the biofilm community, using the single strand conformational polymorphism (SSCP) method, the cloning and sequencing of 16S rRNA gene (16S rDNA) sequences, and the Biolog microplate system. The hypothesis stating that indigenous UMB would play a significant role of in the biofilm development was corroborated. Within 13 days of stimulation, the UMB produced 700 mg L?1 of planktonic EPS and formed a biofilm up to a thickness of 1100 mm. This stimulation led to a decrease in genetic diversity and an increase in metabolic diversity. The decrease in genetic diversity was shown by a reduced number of single strand DNA fragments in the SSCP profiles. As such, 16S rDNA sequences from the biofilm revealed the predominance of four bacterial groups: Zoogloea, Bacillus/Paenibacillus, Enterobacteriaceae, and Pseudomonads. A significant increase in metabolic diversity was shown by a highest substrate richness profile and a lower substrate evenness profile of the biofilm bacterial population (p = 0.0 and p = 0.09, respectively). This higher metabolic diversity might be a consequence of the stimulation that seemed to favor the growth of bacteria having a high nutritional versatility. Stimulation of UMB, isolated from groundwater, was effective to form a biofilm having a high metabolic biodiversity. This combination of molecular-based and metabolic-based methods expanded the insight into monitoring the changes in bacterial biodiversity.

10.
Sci Total Environ ; 280(1-3): 239-55, 2001 Dec 03.
Article in English | MEDLINE | ID: mdl-11763270

ABSTRACT

This study focused on the influence of soil composition and physicochemical characteristics on the retention and partitioning of Cu, Cr and As in nine chromated copper arsenate (CCA) artificially contaminated soils. A statistical mixture design was used to set up the number of soils and their respective composition. Sequential extraction and modified solvent extraction were used to assess Cu and Cr partitioning and As speciation [As(III) or As(V)]. It was found that peat had a strong influence on CEC (232 meq/100 g), on buffer capacity and on Cu and Cr retention, whereas kaolinite's contribution to the CEC was minor (38 meq/100 g). Average metal retention in mineral soils was low (58% for Cu and 23% for Cr) but increased dramatically in highly organic soils (96% for Cu and 78% for Cr). However, both organic and mineral soils demonstrated a very high sorption of added As (71-81%). Levels of Cu and Cr in a soluble or exchangeable form (F1) in highly organic soils were very low, whereas the levels strongly bound to organic matter were much higher. Conversely, in mineral soils, 47% of Cu and 18% of Cr were found in F1. As a result, Cr and Cu in moderately and highly organic contaminated soils were present in less mobile and less bioavailable forms, whereas in mineral soils, the labile fraction was higher. The modified method used for selective determination of mineral As species in CCA-contaminated soils was found to be quantitative and reliable. Results revealed that arsenic was principally in the pentavalent state. Nevertheless, in organic soils, arsenite was found in significant proportions (average value of 29% in highly organic soils). This indicates that some reduction of arsenate to arsenite occurred since the original species in CCA is As(V).


Subject(s)
Arsenates/chemistry , Arsenic/chemistry , Chromium/chemistry , Copper/chemistry , Soil Pollutants/analysis , Arsenates/analysis , Arsenic/analysis , Biological Availability , Chemical Phenomena , Chemistry, Physical , Chromium/analysis , Copper/analysis , Environmental Monitoring , Models, Theoretical , Solubility , Solvents
11.
Water Sci Technol ; 44(9): 287-93, 2001.
Article in English | MEDLINE | ID: mdl-11762475

ABSTRACT

The use of air biofiltration for the degradation of dichlorobenzenes (1,2-DCB and 1,4-DCB) was studied at a refinery site. At this plant, 93 m3/h of contaminated groundwater, used in a cooling system and containing a maximum of 2 ppm of dichlorobenzenes, had to be treated. Stripping of the DCBs followed by biofiltration was selected as the most suitable technology to avoid volatilization in ambient air as expected with a wastewater aerobic treatment system. A stripper of 15 m height and 1.27 m diameter was designed as a first step treatment to volatilize DCBs with 3400 m3/h of air. Two f ull-scale biofilters of 70 m3 each were built and filled with 45 m3 of filtering media for the adsorption and biodegradation of the DCBs in the gas-phase. Filtering media was composed mainly of peat moss, with animal manure, wood chips and DCBs contaminated soil. Air to be treated was also contaminated with naphthalene. Laboratory tests showed an effective microbial activity in the contaminated soil and in the filtering media for DCBs degradation. Degradation of naphthalene induced slower degradation of DCBs. Full-scale operation was studied during four months. Water flow and DCBs content in the water entering the stripper were lower than expected with only 57 m3/h and a maximum concentration of only 240 ppb. Effective desorption was obtained in the stripper in the full-scale operation (more than 99% removal). Full-scale biofilters maintained a DCB concentration of less than 1 ppmv in the air outlet, but removal efficiency varied between 0 and 79% because of the low DCB inlet concentrations, load variations and sporadic naphthalene presence.


Subject(s)
Benzene Derivatives/metabolism , Chlorine Compounds/metabolism , Environmental Pollutants/metabolism , Adsorption , Bacteria, Aerobic/physiology , Biodegradation, Environmental , Filtration , Manure , Refuse Disposal , Volatilization , Water Movements
12.
FEMS Microbiol Lett ; 184(2): 261-4, 2000 Mar 15.
Article in English | MEDLINE | ID: mdl-10713431

ABSTRACT

A new most probable number (MPN) method for the determination of pentachlorophenol (PCP) degraders in soil using the change in pH due to PCP degradation is compared with a well documented MPN method using radiolabeled PCP. The results of all MPN counts were similar within a 95% confidence limit. The results obtained in MPN per gram of dry soil using pH measurements were 1.8 (+3.1, -1.03) x10 (4) compared to 0.64 (+1.34, -0.42) x 10(4) when using production of [(14)C]CO(2).


Subject(s)
Bacteria/growth & development , Bacteria/metabolism , Pentachlorophenol/metabolism , Soil Microbiology , Soil Pollutants/metabolism , Bacteriological Techniques , Biodegradation, Environmental , Carbon Dioxide/metabolism , Carbon Radioisotopes/metabolism , Colony Count, Microbial , Hydrogen-Ion Concentration
13.
Microb Ecol ; 40(4): 345-356, 2000 Dec.
Article in English | MEDLINE | ID: mdl-12035093

ABSTRACT

The microbiota of completely mixed soil slurry was acclimated with pentachlorophenol (PCP) or with a wood preservative mixture (WPM) containing several pollutants such as PCP and petroleum hydrocarbons. The impact of these compounds on the bacterial diversity was studied by using molecular tools. PCR amplifications of the 16S ribosomal RNA gene sequences (rDNA) were carried out with total DNA extracted from soil slurry samples taken at different time points during the enrichment process of the PCP and WPM reactors. The composition of these PCR products, reflecting the bacterial diversity, was monitored by the single-strand-conformation polymorphism (SSCP) method. Our results showed that the complexity of the SSCP profiles in the PCP reactor decreased significantly during the enrichment process, whereas they remained complex in the WPM reactor. PCR-amplified 16S rDNA libraries were generated from each reactor. The SSCP method was used to rapidly screen several clones of these libraries to find specific single-strand DNA migration profiles. In the PCP-activated soil, 96% of examined clones had the same SSCP profile, and sequences of representative clones were related to the genus Sphingomonas, suggesting that the enrichment with PCP resulted in a selection of little phylogenetic diversity. Four different SSCP profiles were observed with the 68 examined clones from the WPM reactor. Representative clones of these profiles were related to Methylocystaceae or Rhizobiaceae, to sulfur-oxidizing symbionts, to the genus Acinetobacter, and to the genus Sphingomonas. We also cloned and sequenced PCR-amplified DNA related to the pcpB gene, coding for the Sphingomonas PCP-4-monooxygenase and detected in both reactors after two weeks of enrichment. Of the 16 examined clones, deduced amino acid sequences of 13 clones were highly related to the Sphingomonas sp. strain UG30 pcpB. The three remaining pcpB clones were not closely related to the three known Sphingomonas pcpB.

14.
CMAJ ; 161(8): 951-5, 1999 Oct 19.
Article in English | MEDLINE | ID: mdl-10551190

ABSTRACT

BACKGROUND: The influence of organizational factors on the process and outcomes of the treatment of breast cancer has been extensively investigated. Although the quality of care is presumed to be better in larger centres, evidence is inconsistent. This study was conducted to determine whether therapies for patients with breast cancer varied according to hospital caseload. METHODS: Women newly diagnosed between 1988 and 1994 with early-stage node-negative primary breast cancer were randomly selected from the Quebec tumour registry and the Quebec hospital discharge database. Data were collected from medical charts, and only women having undergone dissection of the axilla were included in the analyses. Logistic regression analysis was used to adjust for case mix and organizational variables. RESULTS: The final sample included 1259 patients with node-negative stage I or II primary breast cancer. The proportion of women who underwent breast-conserving surgery increased significantly with hospital caseload (from 78.0% in hospitals admitting fewer than 25 new cases each year to 88.0% in those admitting 100 patients or more; p for trend < 0.001). This trend remained significant even after statistical adjustment for case mix and organizational factors (p for trend = 0.001). Of the 1039 women who underwent breast-conserving surgery 965 (92.9%) received radiotherapy. Use of systemic adjuvant therapy (tamoxifen or chemotherapy, or both) increased with the number of patients treated in a given centre (from 60.1% to 68.5%), but this trend disappeared after adjustment for case mix and other factors. The proportion of patients receiving systemic adjuvant therapy consistent with published consensus guidelines tended to increase with caseload for those treated in hospitals participating in multicentre clinical trials but decrease with caseload for patients in hospitals not involved in clinical research. INTERPRETATION: The care of patients in Quebec with early-stage breast cancer is characterized by a high prevalence of both breast-conserving surgery and systemic adjuvant therapy. Large centres, especially those actively involved in clinical research, rapidly adopt innovative therapeutic modalities.


Subject(s)
Breast Neoplasms/surgery , Health Facility Size/standards , Outcome and Process Assessment, Health Care , Breast Neoplasms/pathology , Chemotherapy, Adjuvant , Diagnosis-Related Groups , Female , Health Facility Size/organization & administration , Humans , Neoplasm Staging , Practice Guidelines as Topic , Quebec , Radiotherapy, Adjuvant , Regression Analysis , Research
15.
J Clin Oncol ; 17(5): 1413-24, 1999 May.
Article in English | MEDLINE | ID: mdl-10334526

ABSTRACT

PURPOSE: This phase III study compared docetaxel with mitomycin plus vinblastine (MV) in patients with metastatic breast cancer (MBC) progressing despite previous anthracycline-containing chemotherapy. PATIENTS AND METHODS: Patients (n=392) were randomized to receive either docetaxel 100 mg/m2 intravenously (i.v.) every 3 weeks (n=203) or mitomycin 12 mg/m2 i.v. every 6 weeks plus vinblastine 6 mg/m2 i.v. every 3 weeks (n=189), for a maximum of 10 3-week cycles. RESULTS: In an intention-to-treat analysis, docetaxel produced significantly higher response rates than MV overall (30.0% v 11.6%; P < .0001), as well as in patients with visceral involvement (30% v 11%), liver metastases (33% v 7%), or resistance to previous anthracycline agents (30% v 7%). Median time to progression (TTP) and overall survival were significantly longer with docetaxel than MV (19 v 1 weeks, P=.001, and 1 1.4 v 8.7 months, P=.0097, respectively). Neutropenia grade 3/4 was more frequent with docetaxel (93.1 % v62.5%; P < .05); thrombocytopenia grade 3/4 was more frequent with MV (12.0% v 4.1%; P < .05). Severe acute or chronic nonhematologic adverse events were infrequent in both groups. Withdrawal rates because of adverse events (MV, 10.1%; docetaxel, 13.8%) or toxic death (MV, 1.6%; docetaxel, 2.0%) were similar in both groups. Quality-of-life analysis was limited by a number of factors, but results were similar in both groups. CONCLUSION: Docetaxel is significantly superior to MV in terms of response, TTP, and survival. The safety profiles of both therapies are manageable and tolerable. Docetaxel represents a clear treatment option for patients with MBC progressing despite previous anthracycline-containing chemotherapy.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Mitomycins/therapeutic use , Paclitaxel/analogs & derivatives , Taxoids , Vinblastine/therapeutic use , Adult , Aged , Analysis of Variance , Antineoplastic Agents/administration & dosage , Breast Neoplasms/pathology , Disease Progression , Docetaxel , Drug Administration Schedule , Drug Resistance, Neoplasm , Female , Health Status , Humans , Middle Aged , Mitomycins/administration & dosage , Neutropenia/chemically induced , Paclitaxel/administration & dosage , Paclitaxel/therapeutic use , Patient Compliance , Proportional Hazards Models , Prospective Studies , Survival Analysis , Thrombocytopenia/chemically induced , Vinblastine/administration & dosage
16.
J Clin Oncol ; 17(5): 1458-64, 1999 May.
Article in English | MEDLINE | ID: mdl-10334531

ABSTRACT

PURPOSE: We conducted a population-based study in Quebec, Canada, to assess longitudinal changes in systemic adjuvant therapy for node-negative breast cancer. MATERIALS AND METHODS: A stratified random sample was selected among women with newly diagnosed node-negative breast cancer in 1988, 1991, and 1993. Information on the patient, her tumor, source of care, and treatment was abstracted from medical charts. Patients were classified as being at minimal, moderate, or high risk of recurrence on the basis of criteria proposed at the 4th International Conference on Adjuvant Therapy of Primary Breast Cancer (St. Gallen, Switzerland, 1992), and systemic adjuvant treatment received was dichotomized as being consistent or not consistent with consensus recommendations. RESULTS: Overall, 1,578 cases of invasive breast carcinoma were reviewed. The proportion of patients who were given hormonal or cytotoxic treatment increased from 51.7% to 73.1% from 1988 to 1993. Virtually all women at minimal risk were treated in 1991 and 1993 according to the consensus statement. The proportions of women so treated were 75.0% and 65.4% in the moderate- and high-risk categories, respectively, in 1991. In 1993, these proportions were 71.4% and 67.0%, respectively. Omission of chemotherapy, especially in high-risk women with estrogen receptor-negative tumors who were 50 to 69 years of age, was the most frequent inconsistency with guidelines. CONCLUSION: Systemic adjuvant therapy for node-negative breast cancer has gained acceptance. Better understanding of the decision-making process, of the perception of the risks and benefits involved, and of the impact of alternative strategies for the dissemination of consensus recommendations are needed to promote the use of chemotherapy in specific categories of women who are at high risk of recurrence.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Chemotherapy, Adjuvant/trends , Aged , Breast Neoplasms/chemistry , Breast Neoplasms/pathology , Female , Guidelines as Topic , Humans , Longitudinal Studies , Middle Aged , Neoplasm Recurrence, Local , Receptors, Estrogen/analysis , Tamoxifen/therapeutic use
17.
Cancer ; 85(5): 1104-13, 1999 Mar 01.
Article in English | MEDLINE | ID: mdl-10091795

ABSTRACT

BACKGROUND: The goal of this study was to assess variations with age in the management of breast carcinoma and to identify determinants of care received. METHODS: A stratified random sample was selected among women age > or = 50 newly diagnosed with lymph node negative breast carcinoma in Quebec in 1988, 1991, and 1993. Information was abstracted from medical charts. Predictors of definitive locoregional treatment (total mastectomy with lymph node dissection or breast-conserving surgery with both axillary lymph node dissection and radiation therapy) were identified by multiple logistic regression analysis. RESULTS: Overall, 1174 patients age > or = 50 years with breast carcinoma were included. Women age > or = 70 years were much less likely to receive definitive locoregional treatment compared with women ages 50-69 years (48.7% vs. 83.5%; P < 0.0001). Older women were less likely to undergo surgery with breast preservation (76.7% vs. 86.3%; P < 0.0001), radiation therapy (54.7% vs. 90.5%; P < 0.0001), dissection of the axillary lymph nodes (55.6% vs. 86.3%; P < 0.0001), or chemotherapy (1.2% vs. 13.9%; P < 0.0001), but not treatment with tamoxifen (66.4% vs. 64.7%; P = 0.41). Adjusting for comorbidity and other characteristics related to the disease, the hospital, and the attending physician, age remained a strong determinant of the probability of receiving definitive locoregional treatment (odds ratio [OR], 0.14; 95% confidence interval [95% CI], 0.12-0.18 for women age > or = 70 years vs. women ages 50-69 years). The same association was observed when women who did not undergo lymph node dissection but who received systemic adjuvant treatment were considered to have received definitive therapy (OR, 0.13; 95% CI, 0.10-0.17) for women age > or = 70 years vs. women ages 50-69 years). CONCLUSIONS: Less aggressive patterns of care are provided to elderly breast carcinoma patients, independent of comorbidity. This could explain, at least in part, the sustained breast carcinoma mortality in this population.


Subject(s)
Breast Neoplasms/therapy , Age Factors , Aged , Breast Neoplasms/pathology , Combined Modality Therapy , Female , Humans , Middle Aged , Neoplasm Staging , Odds Ratio , Practice Guidelines as Topic , Quality of Health Care , Quebec , Treatment Outcome
18.
Cancer ; 83(10): 2130-8, 1998 Nov 15.
Article in English | MEDLINE | ID: mdl-9827717

ABSTRACT

BACKGROUND: Despite numerous studies of partial mastectomy and psychologic morbidity in the first 24 months following surgery, little is known about the long term psychosocial repercussions of partial and total mastectomy. METHODS: The effect of the type of mastectomy on psychologic adjustment was assessed among 124 breast carcinoma survivors, 47 of whom underwent partial mastectomy and 77 of whom underwent total mastectomy, 8 years after initial treatment. Interviews were also conducted 3 and 18 months after surgery. Psychologic distress was assessed using the Psychiatric Symptom Index. Other outcomes included physical symptoms, patients' perceptions of their own health, satisfaction with the type of surgery performed and with the appearance of the scar, and marital and sexual adjustments. RESULTS: No statistically significant differences between partial and total mastectomy were observed with respect to long term quality of life. Age at diagnosis modified the relation between the type of mastectomy and psychologic distress in both the short term and the long term (P = 0.04). Among women younger than 50 years, partial mastectomy appeared to be protective against distress when compared with total mastectomy. In contrast, among women age 50 years or older, partial mastectomy was associated with higher psychologic distress levels at all interviews. CONCLUSIONS: Assessed globally, partial and total mastectomy appear to be equivalent treatments in terms of patients' long term quality of life. However, both short term and long term distress levels after partial and total mastectomy may depend on patients' age at diagnosis. The findings of this study suggest that the increased use of partial mastectomy may lessen the negative effects of breast carcinoma on younger survivors' quality of life. Nevertheless, total mastectomy may be an appropriate initial treatment for some women who truly choose it.


Subject(s)
Adaptation, Psychological , Breast Neoplasms/psychology , Mastectomy, Segmental/psychology , Mastectomy, Simple/psychology , Quality of Life , Survivors/psychology , Age Factors , Breast Neoplasms/mortality , Breast Neoplasms/surgery , Female , Humans , Mastectomy, Segmental/mortality , Mastectomy, Simple/mortality , Middle Aged , Psychometrics , Socioeconomic Factors
19.
J Clin Oncol ; 16(2): 487-94, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9469332

ABSTRACT

PURPOSE: Quality of life of breast cancer survivors 8 years after diagnosis was compared with that among similarly aged women who had never confronted cancer (controls). METHODS: Survivors of a consecutive series of 227 breast cancer patients first treated in 1984 were approached for this study. Random-digit dialing was used to identify controls with the same age and residential distribution as the survivors. Quality of life was assessed in terms of physical health, functional status, psychologic distress, and social functioning. RESULTS: Participation was obtained from 96% (n = 124) of 129 eligible survivors and 61% (n = 262) of 427 potentially eligible controls. Consistently smaller proportions of survivors reported positive quality-of-life outcomes compared with controls, but these differences were generally small and nonsignificant statistically. When limited to women who remained free of disease over the entire follow-up period (n = 98), survivors' quality of life was similar to that among controls, with the exception of arm problems and sexual satisfaction for those women who lived with a partner. In contrast, survivors who developed recurrence or new primary breast cancer (n = 26) experienced a worse quality of life in all domains except social functioning. CONCLUSION: In most domains and for women without further disease events after diagnosis, quality of life does not seem to be permanently and globally impaired by breast cancer. Consequently, breast cancer survivors who remain free of disease probably do not need organized late psychosocial follow-up to improve quality of life. However, arm problems and sexuality are two areas in which additional effort may be still needed to improve quality of life of long-term survivors.


Subject(s)
Breast Neoplasms/therapy , Quality of Life , Activities of Daily Living , Adult , Aged , Aged, 80 and over , Attitude to Health , Breast Neoplasms/psychology , Female , Humans , Marriage , Middle Aged
20.
Meat Sci ; 48(1-2): 101-13, 1998 Jan.
Article in English | MEDLINE | ID: mdl-22062883

ABSTRACT

Highly extended cook-in-the-bag hams (65% brine/meat), representative of the products currently manufactured in Canada for mass distribution, were prepared using standard industrial equipment. Adherence between the cooked product and its packaging film was evaluated by measuring the force required to peel an excised band of film from the product surface. Overall, film-product adherence did not change after two weeks of refrigerated storage and was not affected by the extent of tumbling (from 360 to 4500 total turns) or by the cooking cycle (constant temperature of 74 °C, constant temperature of 84 °C, or stepwise temperature increase, until core temperature reaches 69 °C). Adherence was considerably reduced, however, when the extended muscles were finely homogenized prior to stuffing. A more detailed analysis of the results suggested that the occasional lack of proper film-product adherence observed in industry during the manufacture of highly extended hams cannot be due to mere deviations from the regular tumbling or cooking cycles. In addition, results point to the necessity of seeking alternative methods to quantify adherence between meat products and their cooking bags.

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