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C Rousseau

Publications and source records attributed to C Rousseau.

At least 19 recordsLinked to original sources
PubMed2006

An evaluation of data quality in a network for surveillance of Mycobacterium tuberculosis resistance to antituberculosis drugs in Ile-de-France region-2001-2002.

We evaluated the French Azay-Mycobacteria network for surveillance of Mycobacterium tuberculosis drug resistance by matching data with those collected through the mandatory notification (MNTB). Sensitivity of Azay was 96% by capture-recapture analysis. Cases reported to MNTB were more often smear-positive than non-reported cases. Concordance of data collected for common cases was excellent for a majority of variables (k > 0.79), excepted for tuberculosis site (k = 0.52). These results suggest a good quality of the network.

Antitubercular Agents↗
PubMed2006

Brown fat in breast cancer patients: analysis of serial (18)F-FDG PET/CT scans.

PURPOSE: It has recently been suggested that FDG accumulation in the brown adipose tissue varies as a function of age, sex and outdoor temperature. The aim of this study was to assess changes in FDG uptake in brown fat in patients based on serial PET/CT scans and to compare our results with previous findings. METHODS: Early response to neoadjuvant chemotherapy in 33 female breast cancer patients was assessed by FDG PET. Five PET/CT scans were performed for each patient. PET/CT images were analysed retrospectively. PET scans were considered positive when diffuse, symmetrical, abnormal "USA" (uptake in supraclavicular area) fat was detected. RESULTS: A total of 163 PET images were analysed. Seventy-four PET scans (45%) revealed abnormal FDG uptake in the supraclavicular area. These foci were present on uncorrected and attenuation-corrected images. FDG uptake was identical on all five scans in only five patients. No significant relationship was found between abnormal FDG uptake and outdoor temperature, age or time interval between chemotherapy and PET. Abnormal FDG uptake in the neck seemed to predominantly occur in patients with a low body mass index (p<0.05). Most significant changes in the PET/CT scan results were observed during chemotherapy with docetaxel (p<0.05). When observed, bilateral uptake in the neck was more intense than background uptake (p<0.00001). CONCLUSION: This study shows that FDG uptake in the neck varies as a function of time, that it is unrelated to age or outdoor temperature, and that bilateral uptake is generally intense.

Adipose Tissue, Brown↗
PubMed2005

The impact of nonvisualization of sentinel nodes on lymphoscintigraphy in breast cancer.

BACKGROUND: This study aimed at evaluating the relationship between the nonvisualization of sentinel nodes (SNs) at lymphoscintigraphy and the intraoperative detection rate, radioactive counts in vivo, and histological status of SNs. METHODS: Two hundred eighty patients with infiltrating breast carcinoma (T0, T(1)/T(2)) underwent preoperative lymphoscintigraphy before gamma probe-guided SN biopsy. RESULTS: The surgical identification rate with a gamma probe was 84.6% (56 of 280) in lymphoscintigraphy-negative patients and 93.2% (224 of 280) in lymphoscintigraphy-positive patients (P < .05) after two subdermal periareolar injections. The average number of SNs per patient was 1.7 in lymphoscintigraphy-negative patients and 2.2 in lymphoscintigraphy-positive patients (P < .01), as assessed by gamma detection. The mean age of lymphoscintigraphy-negative patients was 62 +/- 10 years, versus 55 +/- 13 years for lymphoscintigraphy-positive patients (P < .001). The median radioactive count in dissected SNs identified by gamma detection was 204 cps (range, 4-618 cps) in lymphoscintigraphy-negative patients, versus 606 cps (range, 43-16,928 cps) in lymphoscintigraphy-positive patients (P < .001). The rate of macrometastatic SNs was 40% in lymphoscintigraphy-negative patients, versus 30% in lymphoscintigraphy-positive patients (not significant), whereas the size of involved SNs was 16.6 mm in lymphoscintigraphy-negative patients, versus 13.1 in lymphoscintigraphy-positive patients (P < .05). The micrometastasis detection rate in SNs from lymphoscintigraphy-negative patients was 6.25%, versus 23.3% in lymphoscintigraphy-positive patients (P < .01). CONCLUSIONS: Negative lymphoscintigraphy was observed in 20% of patients and was more frequent in elderly patients. Negative lymphoscintigraphy was predictive of a lower surgical identification rate and fewer detected SNs. These SNs had fewer micrometastases, were fairly large, and tended to harbor metastases.

Adult↗
PubMed2004

Depression and associated organic diseases: are there any specific depressive symptoms? Results from the dialogue-2 survey.

The objective of the survey was to compare depressive symptoms in depression with and without a concomitant organic disease. The results based on the HAD and CES-D scales showed that, compared to those with an isolated depression, the patients with an associated chronic organic disease have a higher score on two items on the HAD. Three variables on the CES-D scale also helped to differentiate the two groups of depressed patients. No significant difference was found between the two groups in terms of anxiety or cognitive symptoms, fatigue or feelings of disability. Our results do not indicate any symptom that is specific to a combination of depression and somatic diseases. Guilt and hostility showed a lower level in depression associated with a concomitant somatic disease than in isolated depression.

Depression↗
PubMed2004

Interest of F-18 fluorodeoxyglucose positron emission tomography in the evaluation of vaginal malignant melanoma.

BACKGROUND: This is the first report of FDG-PET findings in a case of vaginal melanoma. CASE: The tumor arose from the anterior wall of the vaginal canal. As the tumor was limited to the vaginal wall and as there was no evidence of distant metastases, the disease was staged as IIC (AJCC 2002). PET-CT images showed two mediastinal foci localized to the left highest mediastinal and subcarinal nodes on fusion PET/CT images. As it was metastatic, the disease was staged IV (AJCC 2002). CONCLUSION: In comparison to conventional imaging, FDG-PET provides a more accurate assessment of the extent of disease spread in patients with vaginal melanoma as with cutaneous melanoma. Significant alterations in the surgical management and treatment were made based on PET results.

Female↗
PubMed2003

Learning curve for the detection of axillary sentinel lymph node in breast cancer.

AIM: Sentinel axillary lymph node (SALN) detection is a new technique. Surgeons must progress up a learning curve in order to guarantee quality and safety equivalent to axillary lymphadenectomy. To ensure accurate staging of patients this learning curve must include SALN detection and an axillary lymphadenectomy. The aim of our work was to validate the principles and evaluate the consequences of learning curve for SALN detection from a prospective series of 200 consecutive patients. METHOD: Prospective assessment was made of the detection and false negative rates, post operative morbidity as abcess and seroma, and length of hospital stay. RESULTS: We evaluated the performance from the first to the hundredth case for each surgeon. Detection rate improved to 85% after patient number 10. False negative rate was less than 6%. Post operative axillary morbidity included 11% of seromas and 2% of abcess. Mean hospital stay was 2.8 days. CONCLUSION: Multidisciplinary validation of the learning period contributes to an accurate and safe SALN.

Adult↗
PubMed2003

Growth hormone and milking frequency act differently on goat mammary gland in late lactation.

In ruminants, milk yield can be affected by treatment with growth hormone (rbGH) and/or changes in frequency of milking. Frequent milkings encourage the maintenance of lactation, whereas infrequent milkings result in mammary involution. Our objective was to evaluate the influence of rbGH treatment and milking frequency on mammary gland morphology and milk composition. After adaptation to twice-daily milkings, six Saanen goats in late lactation were milked once daily from one udder-half and thrice-daily from the other udder-half. Concurrently, three of the six goats received daily injections of rbGH. After 23 d of treatment, milking frequency significantly affected milk yield (+8% vs. -26% for thrice- vs. once-daily milking). Additionally, treatments of rbGH increased milk yield from thrice-daily milked udder-halves (+19%), but failed to abate the reduction in milk yield from once-daily milked udder-halves (-31%). Mammary glands were heavier in the frequently milked udder-halves and in GH-treated goats. Based on histological and DNA analysis of mammary tissues, it was determined that milking frequency clearly affected epithelial cell numbers and alveolar diameter, whereas rbGH induced a potential cell hypertrophy and only a tendency to increase and/or maintain the mammary cell number. RNA concentration and kappa casein gene expression were not affected by treatments. In udder-halves milked once-daily, low casein:whey protein ratios, high Na+:K+ ratios, and high somatic cell counts (SCC) were indicative of changes in epithelial permeability, which rbGH treatment facilitated. The present data suggest that milking frequency and exogenous treatments of rbGH use different cellular mechanisms to influence mammary gland morphology and milk production.

Animals↗
PubMed2002

The cellular prion protein: a new partner of the lectin CBP70 in the nucleus of NB4 human promyelocytic leukemia cells.

Prion diseases are characterized by the presence of an abnormal isoform of the cellular prion protein (PrPc) whose physiological role still remains elusive. To better understand the function of PrPc, it is important to identify the different subcellular localization(s) of the protein and the different partners with which it might be associated. In this context, the PrPc-lectins interactions are investigated because PrPc is a sialoglycoprotein which can react with lectins which are carbohydrate-binding proteins. We have previously characterized a nuclear lectin CBP70 able to recognize N-acetyl-beta-D-glucosamine residues in HL60 cells. Using confocal immunofluorescence, flow-cytofluorometry, and Western-blotting, we have found that PrPc is expressed in the nucleus of the NB4 human promyelocytic leukemia cell line. It was also found that the lectin CBP70 is localized in NB4 cell nuclei. Moreover, several approaches revealed that PrPc and CBP70 are colocalized in the nucleus. Immunoprecipitation experiments showed that these proteins are coprecipitated and interact via a sugar-dependent binding moiety. In conclusion, PrPc and CBP70 are colocalized in the nuclear compartment of NB4 cells and this interaction may be important to better understand the biological function and possibly the conversion process of PrPc into its pathological form (PrPsc).

Blotting, Western↗
PubMed2001

Going home: giving voice to memory strategies of young Mayan refugees who returned to Guatemala as a community.

Around 1982, thousands of Guatemalan Mayas fled their villages and lands to escape the Rios Montt scorched-earth policy implemented in rural areas. After more than a decade of exile, many of those refugees have returned to their homeland. This paper looks at the ways in which young Mayan refugees who have returned home after extended exile in Mexico appropriate and distance themselves from the collective project of going home. Two Mayan communities of retornados (returnees), whose paths into exile and home again differ slightly, are compared. Outside support from international organizations and cohesion in the refugee camps enabled the young people of La Victoria to see disclosure of the traumatic past from a position of strength and confrontation as the key to social change. In La Esperanza, the past is rebuilt by the youth around avoidance of recent history, and tradition appears as a bridge between past and future. The way the youth of the two communities construct their homecoming demonstrates how small changes in the migration experience may result in considerable differences in the choice of strategies, and raises important questions about assistance programs that might be developed for these populations.

Adolescent↗
PubMed2001

Immunotherapy of established tumors in mice by intratumoral injection of an adenovirus vector harboring the human IL-2 cDNA: induction of CD8(+) T-cell immunity and NK activity.

Intratumoral (i.t.) injections of an adenovirus encoding the human interleukin-2 (IL-2) under the control of the RSV (Ad-pRSV-IL-2) or CMV (Ad-pCMV-IL-2) promoter were performed in established mastocytoma P815 tumors in B6D2 mice. Both early and long-term survival were found increased in mice treated with Ad-pCMV-IL-2 as compared with those obtained with Ad-pRSV-IL-2: tumor regression was observed in 30--50% of mice for the former and 5--15% for the latter. Difference in efficacy between the two vectors was directly correlated to the amount of IL-2 produced i.t. between 24 and 48 hours postinjection, which reached 10--20 ng/tumor for Ad-pCMV-IL-2 and 0.3--0.5 ng/tumor for Ad-pRSV-IL-2. In both cases, expression in the tumor was clearly detectable for a period of 7--10 days postinjection. Serum IL-2 was not detectable in mice treated with Ad-pRSV-IL-2, whereas expression peaked at a total of 1--2 ng at 24 hours but declined very rapidly in the Ad-pCMV-IL-2-treated group. Constant production of IL-2 inside the tumor was necessary for successful therapy because i.t. injections of recombinant IL-2 at levels up to 1 microg for five consecutive days did not lead to antitumoral activity. Evidence of induced systemic immunity following Ad-pCMV-IL-2 injections was obtained from rechallenge experiments in which tumor-free mice after treatment rejected a subsequent contralateral injection of a lethal dose of P815 tumor cells and from the observation that regression of nontreated tumors occurred in animals bearing bilateral tumors that were treated i.t. in a single tumor with Ad-pCMV-IL-2. P815-specific cytotoxic T lymphocytes (CTL) were found specifically in spleen cells from cured mice or rechallenged mice but not in control mice. Interestingly, limiting dilution analysis of anti-P815 CTL precursor (CTLp) frequency revealed a significant increase in mice cured of their tumor as compared to that obtained in naive mice or control mice treated or not with Ad-IL-2 but whose tumor was growing. In vivo depletion of T-cell subsets, as well as natural killer cells at the time of i.t. injections with Ad-pCMV-IL-2, demonstrated that both CD8(+) T cells and natural killer cells, but not CD4(+) T cells, were required for successful therapy. Finally, mice preimmunized with Ad-null viruses were severely compromised in their capacity to eradicate established P815 tumors after Ad-pCMV-IL-2 therapy, at least when neutralizing antibody titers reached a critical level.

Adenoviridae↗
PubMed2001

Trauma and extended separation from family among Latin American and African refugees in Montreal.

Although the vast majority of refugees have suffered trauma and extended separation from their families in exile, little is known about the interactions between these two types of experience. The qualitative and quantitative analyses of data gathered from 113 refugees from Latin America and Africa suggest that the joint occurrence of trauma and separation has a significant impact on emotional distress and confirm that the family plays a key role as an anchor of emotion and identity.

Adult↗
PubMed2000

Glycosylated nuclear lectin CBP70 also associated with endoplasmic reticulum and the Golgi apparatus: does the "classic pathway" of glycosylation also apply to nuclear glycoproteins?

The subcellular plurilocalization of some lectins (galectin-1, galectin-3, galectin-10, calreticulin, etc.) is an intriguing problem, implying different partners according to their localization, and involvement in a variety of cellular activities. For example, the well-known lectin, galectin-3, a lactose-binding protein, can act inside the nucleus in splicing events, and at the plasma membrane in adhesion, and it was demonstrated that galectin-3 interacts in the cytoplasm with Bcl-2, an antiapoptotic protein. Some years ago, our group isolated a nuclear lectin CBP70, capable of recognizing N-acetylglucosamine residues. This lectin, first isolated from the nucleus of HL60 cells, was also localized in the cytoplasm. It has been demonstrated that CBP70 is a glycosylated lectin, with different types of glycosylation, comparing cytoplasmic and nuclear forms. In this article, we have studied the localization of CBP70 in undifferentiated HL60 cells by electron microscopy, immunofluorescence analysis, and subcellular fractionation. The results obtained clearly demonstrated that CBP70 is a plurilocalized lectin that is found in the nucleus, at the endoplasmic reticulum, the Golgi apparatus, and mitochondria, but not at the plasma membrane. Because CBP70, a nuclear glycoprotein, was found to be associated also with the endoplasmic reticulum and the Golgi apparatus where the glycosylation take place, it raised the question: where does the glycosylation of nuclear proteins occur?

Cell Nucleolus↗
PubMed2000

Stable expression of functional CBP70 lectin during heat shock.

CBP70 is a glycoslylated lectin that interacts through either glycan-lectin or protein-protein interactions. In addition, depending on its cellular localization, this lectin has different partners, for example, galectin-3, an 82-kDa ligand in the nucleus, or Bcl-2 in the cytoplasm. In this study, we observed the persistence of plurilocalized lectin CBP70 after two heat-shock treatments conducted either under mild conditions, i.e., incubating the cells for 1 h at 42 degrees C then for 1, 3, 5, 7, or 9 h at 37 degrees C, or harsh conditions, i.e., incubation at 42 degrees C for 1, 2, 4, 6, 8, or 10 h. By combining the information collected from biochemical, fluorocytometric, confocal, and affinity-chromatography analyses, we concluded that CBP70 persisted in HL60 cells and its N-acetylglucosamine-binding sites remained active after all the heat-shock treatments tested. These data and the previously published findings reviewed in this report concur in supporting the hypothesis that CBP70 could function as an organizer of multimeric assembly, leading to the formation of various complexes in different cellular compartments, according to the needs of the cell.

Acetylglucosamine↗
PubMed2000

Treatment of bone metastases of prostate cancer with strontium-89 chloride: efficacy in relation to the degree of bone involvement.

This retrospective study evaluated the toxicity and efficacy of strontium-89 chloride (Metastron, Amersham) in 94 patients with painful bone metastases of prostate cancer (117 injections of 150 MBq) and compared the efficacy of treatment in patients with moderate and extensive bone involvement. The predictive value of flare response with regard to analgesic response was also studied. High-grade leukothrombopenias were observed after only 5% of injections. An improvement in quality of life was obtained in 65% of cases, a decrease in pain in 78% (31% complete response) and a reduction of analgesics in 60%. Efficacy was significantly better for pain decrease (P=0.005) and reduction of analgesics (P=0.018), and response was significantly longer (P<0.0035) in patients with moderate than in patients with extensive bone involvement. The flare response observed in 23% of cases was not predictive of pain response (P=0.919) or reduction of analgesics (P=0.353). A second dose prolonged analgesia in three-quarters of cases without any apparent increase in toxicity. These results confirm the benefit of 89Sr chloride for the treatment of metastatic bone pain and suggest that internal radiotherapy should be started earlier. A bone scan could be proposed at the time of hormonal escape resulting in bone pain, and internal radiotherapy could be initiated when several metastatic foci exist, even if only one is painful. In this way, pain-free follow-up could be prolonged, and the transition to other therapeutic approaches, particularly opioids, delayed.

Aged↗
PubMed2000

Nuclear medicine applications for neuroendocrine tumors.

Sensitive, specific radiopharmaceuticals are available for scintigraphic diagnosis and internal radiotherapy of neuroendocrine tumors. (123)I-MIBG (metaiodobenzylguanidine) scintigraphy is the examination of choice for visualizing tumor sites of pheochromocytoma. In the event of malignant pheochromocytoma or carcinoid tumor, this examination allows assessment of the presence or absence of tumor uptake and can guide radiotherapy with (131)I-MIBG. The peptides secreted by neuroendocrine tumors can be radiolabeled for targeting of their specific receptors. Scintigraphy using a (111)In-labeled somatostatin analog (octreotide) is the examination of choice for diagnosis of the spread of gastroenteropancreatic and carcinoid tumors, as it is more sensitive than morphologic imaging techniques. It can also guide radiotherapy performed with the same pharmaceutical vector. These same two agents (MIBG and octreotide) can be used therapeutically by replacing (123)I with (131)I and (111)In by (90)Y. A transient palliative effect is obtained for a variable number of tumors (most often large ones) that take up the radiopharmaceutic agent well. There is general consensus that, for relatively radioresistant solid tumors, this type of radiotherapy is efficient only in the event of small tumor targets (a few millimeters in diameter) whose uptake is maximal, allowing more homogeneous distribution than that achieved with large tumors. Thus for optimal control of the disease it is recommended first to use scintigraphic imaging to confirm that the tumor takes up the radiopharmaceutical agent in question ((123)I-MIBG or (111)In-octreotide) and then reduce the tumor burden surgically before injecting high therapeutic activity (possibly with reinjection of peripheral stem cells). This treatment can be repeated three times every 3 months before evaluating the response. In these conditions, internal radiotherapy can be beneficial or even determinant for controlling disease progression.

3-Iodobenzylguanidine↗
PubMed2000

Maternal SDF1 3'A polymorphism is associated with increased perinatal human immunodeficiency virus type 1 transmission.

Genetic polymorphisms in chemokine and chemokine receptor genes influence susceptibility to human immunodeficiency virus type 1 (HIV-1) infection and disease progression, but little is known regarding the association between these allelic variations and the ability of the host to transmit virus. In this study, we show that the maternal heterozygous SDF1 genotype (SDF1 3'A/wt) is associated with perinatal transmission of HIV-1 (risk ratio [RR], 1.8; 95% confidence interval [CI], 1.0 to 3.3) and particularly postnatal breastmilk transmission (RR, 3.1; 95% CI, 1.1 to 8.6). In contrast, the infant SDF1 genotype had no effect on mother-to-infant transmission. These data suggest that SDF1, which is a ligand for the T-tropic HIV-1 coreceptor CXCR4, may affect the ability of a mother to transmit the virus to her infant. This suggests that a genetic polymorphism in a gene encoding a chemokine receptor ligand may be associated with increased infectivity of the index case and highlights the importance of considering transmission as well as clinical outcome in designing chemokine-based therapies for HIV-1.

3' Untranslated Regions↗
PubMed2000

Living conditions and emotional profiles of Cambodian, Central American, and Québécois youth.

OBJECTIVE: To compare Cambodian and Central American adolescent refugees to Quebec with their Quebec-born peers in regard to emotional and behavioural problems, feelings of competence, and risk-behaviour profiles, and to examine relations between emotional variables and living conditions in the 3 groups. METHOD: The sample consisted of 76 Cambodian, 82 Central American and 67 Québécois youth living in the Montreal area. The teenagers' internalization and externalization symptoms were assessed using the Child Behaviour Checklist (CBCL) and the Youth Self-Report (YSR); the YSR also provided a measure of their feelings of competence. Risk behaviour was reported by the teenagers. The socioeconomic status of the teenagers' households was taken into account in multiple regression analyses conducted for each group. RESULTS: The level of emotional and behavioural problems reported by teenagers was lowest in Central Americans and highest in Québécois; the latter group also reported more risk behaviours than did either refugee group. The socioeconomic status of the Cambodian and Central American refugee households was lower than that of the Québécois. Living conditions were not a major determinant of emotional distress in young Cambodians, but low annual income was associated with internalizing symptoms among Central American youth. The most powerful predictor of externalizing symptoms among the Québécois youth was having a single-parent household. CONCLUSION: This study underscores the contrast between the living conditions of young Cambodian and Central American refugees to Quebec and those of Quebec-born youth. These refugees' precarious socioeconomic status is not accompanied by an increase in adolescents' emotional and behavioural problems.

Adolescent↗