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M Plante

Publications and source records attributed to M Plante.

At least 37 records · Page 2Linked to original sources
PubMed1998

Operative laparoscopy prior to a pelvic exenteration in patients with recurrent cervical cancer.

INTRODUCTION: Selecting out the true candidates for a pelvic exenteration frequently poses a difficult clinical dilemma in patients with recurrent cervical cancer after radiation therapy. Despite very thorough preoperative investigation, inoperable disease is discovered at the time of laparotomy in up to 60% of cases. SUBJECTS AND METHODS: In this retrospective analysis, we report the use of operative laparoscopy in 13 patients with either biopsy proven locally recurrent cervical cancer (N = 9) or with clinically suspected tumor recurrence (N = 4). All have previously received radical radiation therapy. RESULTS: Patients' ages ranged from 36 to 79 years (median, 43). The median duration of the procedure was 150 min (range,50-200) and median blood loss was 50 cc (range, 50-200). The procedure was well tolerated in all patients. There was no intraoperative complication. One deep thrombophlebitis occurred postoperatively. The laparoscopic evaluation could not be completed in one case because of a large nonmobile uterine fibroid filling the whole pelvis. At laparoscopy, metastatic tumor was identified in 9 of 12 patients (75%). An unnecessary laparotomy was avoided in 8 of those 9 cases (one had a palliative exenteration). The most common site of metastasis was in the previously radiated pelvis (7/9). Three patients had a negative laparoscopy. Two had an exenteration and one had a transureteroureterostomy. At the time of laparotomy, none were found to have disease that would have been missed at laparoscopy. CONCLUSION: We conclude that operative laparoscopy may be a valuable additional step in the work-up and management of patients with locally recurrent cervical cancer. With experience in retroperitoneal surgery, the procedure can be carried out safely in previously radiated patients. We believe this approach can lower the number of unnecessary laparotomies, reduce the morbidity, and shorten the length of the postoperative recovery.

Adult↗
PubMed1998

Pregnancies after radical vaginal trachelectomy for early-stage cervical cancer.

OBJECTIVE: The purpose of this study was to evaluate the role of fertility-preserving surgery in the treatment of early-stage cervical cancer. STUDY DESIGN: We retrospectively reviewed our first 30 patients treated by laparoscopic pelvic lymphadenectomy, followed by radical vaginal trachelectomy, from October 1991 to April 1998. RESULTS: The median age of the patients was 32 years (range 22-42 years); 15 were nulligravid and 19 nulliparous. Twenty cancers were at stage IB, 1 was at stage IA1, 7 were at stage IA2, and 2 were at stage IIA. The majority (18/30) were squamous. Two lesions were >2 cm in size, and only 4 had vascular space invasion. The median operative time was 285 minutes (range 155-455 minutes), median blood loss 200 mL (range 50-1200 mL), and median hospital stay 4 days (range 2-9 days). There were 4 intraoperative complications-2 attributed to the trachelectomy and 2 resulting from the lymphadenectomy. The current median follow-up time is 25 months (range 1-79 months). One patient had a recurrence in the left parametrium 18 months after vaginal radical trachelectomy and died of metastatic disease. The only 6 patients attempting pregnancy so far have succeeded: 4 have had healthy babies delivered by cesarean section at 39, 38, 34, and 25 weeks of gestation. Two are currently 33 and 8 weeks pregnant. CONCLUSION: Radical vaginal trachelectomy appears to be a valuable procedure in well-selected patients with early-stage cervical cancer. Successful pregnancies are definitely possible after this procedure. This new surgical technique warrants further careful evaluation to determine precise indications.

Adult↗
PubMed1998

T cell-depleted granulocyte colony-stimulating factor (G-CSF) modified allogenic bone marrow transplantation for hematological malignancy improves graft CD34+ cell content but is associated with delayed pancytopenia.

To increase the stem cell content of T cell-depleted bone marrow transplants (BMT), we treated 12 patients with hematological malignancies with BMT from HLA-identical sibling donors given G-CSF 10 microg/kg/day for 5 days before marrow harvest. After CD34+ cell selection, patients received a median of 1.7 (range, 0.82-3.1) x 10(6) CD34+ cells/kg and 2.3 (range, 0.25-4.0) x 10(5) CD3+ cells/kg. All patients had initial engraftment but four developed pancytopenia between days 55-130 post-BMT. In two patients, this required a second infusion of G-CSF-mobilized donor peripheral blood progenitor cells. We observed no delayed pancytopenia in a matched historical group of 24 patients receiving T cell-depleted BMT without prior G-CSF stimulation. Compared to this control group, G-CSF-stimulated marrow recipients showed a significant decline in neutrophil and monocyte counts after 8 weeks. However, outcome after BMT was otherwise comparable, with a similar incidence of acute graft-versus-host disease and transplant-related mortality. Disease-free survival was 63 vs 67% for controls matched for CD34+ cell dose (P = NS). These results indicate that G-CSF stimulation can increase the CD34+ cell content of T cell-depleted marrow but carries a risk of late graft failure.

Adolescent↗
PubMed1998

High incidence of adeno- and polyomavirus-induced hemorrhagic cystitis in bone marrow allotransplantation for hematological malignancy following T cell depletion and cyclosporine.

Nine of 56 (20% actuarial) patients receiving a T cell-depleted, HLA-identical sibling BMT for hematological malignancy developed hemorrhagic cystitis (HC) 15-368 days post BMT. Hematuria was severe and prolonged (median duration 18 days). In eight patients (89%), a viral etiology was confirmed (four adenovirus, four polyomavirus). HC was associated with significant morbidity, with all patients requiring continuous bladder irrigation and transfusion support for blood loss and thrombocytopenia. HC occurring before day 100 was significantly associated with a reduction in long-term survival: 1/7 (14.3%) patients developing HC before day 100 became long-term survivors vs 21/49 (42.8%) without HC by day 100 (P = 0.034). In univariate analysis, HC was associated with a diagnosis of multiple myeloma (P = 0.02). There was a trend towards a higher incidence of HC in patients reactivating cytomegalovirus (CMV) compared with those remaining CMV negative (18.4 vs 5.5% respectively, P = 0.17). HC was not associated with graft-versus-host disease, or with the transplant dose of CD34+ progenitors or CD3+ cells, patient age or sex. Life-threatening, viral-induced HC and the unusually high incidence of adenovirus-induced HC may have been caused by immune deficiency associated with T cell depletion in this series.

Adenoviridae Infections↗
PubMed1997

Local expression of cytokines in rat bladder carcinoma tissue after intravesical treatment with Nocardia rubra cell wall skeleton and bacille-Calmette-Guerin.

This study aimed to investigate local immunotherapy with Nocardia rubra cell wall skeleton (N-CWS) and bacille-Calmette-Guerin (BCG) in chemically induced rat bladder carcinoma. After being fed with 0.025% N-butyl-N-(4-hydroxybutyl) nitrosamine for 26 weeks, female Wistar rats were treated once a week by intravesical instillation of 100 microg N-CWS or 5 x 10(6) Colony-Forming Units (CFU) BCG. Tissue specimens were obtained 4 h after the ninth instillation and analyzed by reverse transcription polymerase chain reaction (RT-PCR) for mRNA expression of rat cytokines. The analysis showed high expression of interleukin (IL)-1 alpha, tumor necrosis factor (TNF)-alpha, IL-2, and interferon (IFN)-tau in BCG (7/7, 7/7, 7/7, 5/7) and N-CWS (9/9, 9/9, 8/9, 8/9) treated tumors in comparison to low expression in controls (3/9, 0/9, 3/9, 3/9). Interestingly, intravesical instillation of N-CWS tended to be less effective at preventing local invasion of the tumors. It is speculated that this difference may result from a more strongly induced expression of T-helper cell-derived lymphokines (IL-2, IFN-tau) by BCG.

Actins↗
PubMed1997

Antithymocyte globulin for patients with myelodysplastic syndrome.

Twenty-five transfusion-dependent myelodysplastic syndrome (MDS) patients (with < 20% blasts) were treated in a phase II study with antithymocyte globulin (ATG) at 40 mg/kg/d for four doses and then followed with blood counts every 2 weeks and clinic visits every 3 months, for a median of 14 months (range 1-38 months). 11 (44%) patients responded and became transfusion-independent after ATG, including three complete responses, six partial responses, and two minimal responses. Responses were observed in 9/14 patients (64%) with refractory anaemia (RA) and 2/6 patients (33%) with refractory anaemia with excess blasts (RAEB). Median response duration was 10 months (range 3-38 months). The Kaplan-Meier estimate of overall survival was 84% at 38 months, with one early death due to pneumonia and two deaths from disease progression to leukaemia. Side-effects consisted mainly of mild serum sickness in all patients. A single course of ATG restored haemopoiesis in some patients with MDS and was well tolerated.

Adult↗
PubMed1997

Detection of a homologue of bcl-2 in plant cells.

An emerging family of bcl-2-like genes has been identified from nematode to humans. These genes play a role in the maintenance of homeostasis. Its members have highly conserved domains that are important for their dimerization. Since nothing is known about the importance of these genes in plant cells, we have investigated their presence in an alga as well as in three higher plants both by Western analysis and by immunocytochemistry. Immunoblots revealed the presence of a protein immunoreacting with the anti-bcl-2 polyclonal antibody in leaves of tobacco plants. Furthermore, immunocytochemical localization has shown that this protein is mainly associated with mitochondria, plastids, and nuclei of plant cells. Taken together, our results suggest that bcl-2 is a protein highly conserved throughout evolution.

Animals↗
PubMed1996

Human perception of electric fields and ion currents associated with high-voltage DC transmission lines.

The objective of this study was to assess the ability of humans to detect the presence of DC electric field and ion currents. An exposure chamber simulating conditions present in the vicinity of high-voltage DC (HVDC) lines was designed and built for this purpose. In these experiments, the facility was used to expose observers to DC electric fields up to 50 kV/m and ion current densities up to 120 nA/m2. Forty-eight volunteers (25 women and 23 men) between the ages of 18 and 57 years served as observers. Perception of DC fields was examined by using two psychophysical methods: an adaptive staircase procedure and a rating method derived from signal-detection theory. Subjects completed three different series of observations by using each of these methods; one was conducted without ion currents, and the other two involved various combinations of electric fields and ion currents. Overall, subjects were significantly more likely to detect DC fields as the intensity increased. Observers were able to detect the presence of DC fields alone, but only at high intensities; the average threshold was 45 kV/m. Except in the most sensitive individuals, ion current densities up to 60 nA/m2 did not significantly facilitate the detection of DC fields. However, higher ion current densities were associated with a substantial lowering of sensory thresholds in a large majority of observers. Data analysis also revealed large variations in perceptual thresholds among observers. Normative data indicating DC field and ion current intensities that can be detected by 50% of all observers are provided. In addition, for the most sensitive observers, several other detection proportions were derived from the distribution of individual detection capabilities. These data can form the basis for environmental guidelines relating to the design of HVDC lines.

Adolescent↗
PubMed1996

Vaginal radical hysterectomy versus abdominal radical hysterectomy in the treatment of early-stage cervical cancer.

The purpose of this study is to compare the safety, efficacy, and potential benefits of vaginal radical hysterectomy (VRH) versus abdominal radical hysterectomy (ARH) in the treatment of early-stage cervical cancer. We reviewed the charts of our first 52 patients with cervical cancer. We reviewed the charts of our first 52 patients with cervical cancer who underwent a laparoscopic pelvic lymphadenectomy (LPL), followed either by a VRH (Schauta) in 25 cases or ARH in 27 cases. For the 52 patients, the mean lymph nodes count obtained by LPL was 27 (range 8-59), and the only complication was an external iliac vein trauma requiring laparotomy. Both VRH and ARH groups were comparable in terms of age, weight, parity, stage, histology, and tumor volume. The mean blood loss was 400 cc for VRH vs 450 cc for ARH, operating time was 270 min vs 280 min, blood transfusion in 5 vs 4 women, and postoperative stay was 7 days for both groups. The only intraoperative complication in addition to the vein trauma was a cystotomy which occurred in 2 VRH patients. Febrile morbidity was noted in 4 VRH patients vs 9 ARH patients. There were one preperitoneal abscess and one hematoma in the VRH group vs 4 wound infections and 1 hematoma after ARH. Ileus occurred in 1 VRH vs 4 ARH patients. The current mean follow-up time is 27 months (8-52) and there has been one recurrence so far in the ARH group. Even though this is a retrospective study, our data indicate that VRH and ARH are comparable, except for the absence of an abdominal scar and less febrile morbidity with the vaginal approach. However, in our opinion, the main advantage in learning the Schauta operation is that the experience gained allows one to offer radical trachelectomy to selected young patients who wish to preserve their fertility.

Adult↗
PubMed1996

The international prostate symptom score: physician versus self-administration in the quantification of symptomatology.

OBJECTIVES: The International Prostate Symptom Score (IPSS), originally known as the American Urological Association Score, is the most commonly used scoring system for the quantification of benign prostatic hyperplasia symptoms. One area that has remained unexplored is the stability of the questionnaire construct between different modes of administration. The objective of this study was to measure differences in IPSS when administered by the physician versus patient self-administration. The impact of order of administration was also examined. METHODS: Sixty-four patients completed two IPSS questionnaires during the same office visit, one self-administered and the other by physician interview. The influence of order of administration was examined by randomly allocating patients to either self-administration or physician-administration first. Total symptom scores (questions 1 to 7) and quality of life scores (question 8) were compared between the two modes of administration. Multivariate analysis of variance was performed to assess the effect of age, medical history (obtained from the IPSS form), order of administration, and physician (A and B) on the observed differences. RESULTS: The distribution of differences was similar between the two orders of administration. Overall, 26 patients had a higher total score with self-administration, 30 with physician-administration, and 8 had identical scores on both. Mean total symptom scores and quality of life assessments by physician- versus patient-administered questionnaires were similar (10.9 versus 10.4 and 1.8 versus 2.2, respectively). No statistically significant difference was observed. The order of administration did not show statistical significance (P > 0.05) by multivariate analysis. As well, no interaction was seen between the aforementioned variables. CONCLUSIONS: There is no difference in the information obtained if patients self-administer the questionnaire as opposed to physician administration.

Aged↗
PubMed1995

The use of operative laparoscopy in determining eligibility for pelvic exenteration in patients with recurrent cervical cancer.

In patients with suspected recurrent cervical cancer after radiation therapy, it can be very difficult to pathologically confirm recurrence and clinically determine if tumor is resectable via a curative pelvic exenteration. Despite very thorough preoperative investigation uncertainties often remain, so patients ultimately undergo exploratory laparotomy. Unfortunately, inoperable disease is frequently discovered then. We report the use of operative laparoscopy in three patients with recurrent stage IIIB cervical cancer. The age ranged from 38 to 79 years. The mean duration of the procedure was 146 min (range 110-180 min) and blood loss was minimal. The procedure was well tolerated in all patients. There was no intraoperative complication but one deep thrombophlebitis occurred postoperatively. The procedure was successful in all cases in confirming recurrence and selecting out patients who were not surgical candidates for pelvic exenterations. Operative laparoscopy is a less invasive procedure that may be a valuable step in the workup of patients with recurrent cervical cancer. With experience in retroperitoneal surgery, the procedure can be carried out safely. We believe that this approach could prevent unnecessary laparotomies, shorten the hospital stay and the postoperative recovery, and contribute to a better quality of life for women with inoperable disease.

Adult↗
PubMed1995

Family history and the risk of prostatic carcinoma in a high risk group of urological patients.

PURPOSE: We examine the association of family history and prostatic carcinoma. MATERIALS AND METHODS: A total of 2,968 consecutive patients referred for prostate cancer detection responded to a questionnaire and underwent transrectal ultrasound examination with or without biopsy. RESULTS: Of the men 329 (11.1%) had a family history of prostate cancer. No differences were observed between groups with and without a family history with respect to mean patient age, serum prostate specific antigen level or biopsy rate. Prostate cancer was detected in 133 of 329 patients (40.4%) with a family history and 769 of 2,639 (29.1) with no family history (p < 0.001, odds ratio 1.7). No significant differences were observed between cancer patients with or without a family history with respect to mean Gleason score (6.0 versus 6.2), patient age at diagnosis (65.8 versus 66.7) and prostate specific antigen level (16.8 versus 17.1). CONCLUSIONS: Patients with a family history of prostate cancer have a greater risk of the disease. In this select group of patients a positive family history was not associated with an earlier age at cancer diagnosis or a different histological grade of tumor.

Aged↗
PubMed1995

A common gene for juvenile and adult-onset primary open-angle glaucomas confined on chromosome 1q.

Primary open-angle glaucoma (POAG), which causes progressive loss of the visual fields, was subdivided into two groups according to age at onset: (1) chronic open-angle glaucoma (COAG) diagnosed after age 40 years and (2) juvenile open-angle glaucoma (JOAG) diagnosed between 3 years of age and early adulthood. A JOAG gene (GLC1A) was recently mapped to chromosome 1q. We studied 142 members of a huge multigenerational French Canadian family affected with autosomal dominant POAG. Either JOAG or COAG was diagnosed in 40 patients. Six subjects were also diagnosed with ocular hypertension (OHT), which may lead to POAG. To localize a common disease gene that might be responsible for both glaucoma subsets, we performed linkage analysis considering JOAG and COAG under the same phenotypic category. JOAG/COAG was tightly linked to seven microsatellite markers on chromosome 1q23-q25; a maximum lod score of 6.62 was obtained with AF-M278ye5. To refine the disease locus, we exploited a recombination mapping strategy based on a unique founder effect. The same characteristic haplotype, composed of 14 markers spanning 12 cM between loci D1S196 and D1S212, was recognized in all persons affected by JOAG, COAG, or OHT, but it did not occur in unaffected spouses and in normal family members > 35 years of age, except for three obligatory carriers. Key recombination events confined the disease region within a 9-cM interval between loci D1S445 and D1S416/D1S480. These observations demonstrate that the GLC1A gene is responsible for both adult-onset and juvenile glaucomas and suggest that the JOAG and COAG categories within this family may be part of a clinical continuum artificially divided at age 40 years.

Adolescent↗
PubMed1994

Interleukin-6 level in serum and ascites as a prognostic factor in patients with epithelial ovarian cancer.

BACKGROUND: Interleukin-6 (IL-6) is a multifunctional cytokine that can be produced by human ovarian cancer cells. Elevated IL-6 levels have been found in the serum and ascites of patients with ovarian cancer, but its role in this disease has not been clearly established. METHODS: The authors studied the relationship between IL-6 levels in serum and ascites, various tumor parameters, and survival in 70 patients with newly diagnosed, untreated epithelial ovarian cancer. Ascites and serum specimens were obtained at the time of initial surgery, and IL-6 levels were determined using the B9 bioassay. RESULTS: All patients underwent platinum-based chemotherapy after initial surgery. The median age of the group was 62 years (range, 28-87 years), and the median follow-up time was 13 months (range, 12-59 months). Significantly higher IL-6 levels were detected in patients' ascites (median, 49,612 pg/ml [range, < 1 to 680,330 pg/ml]) compared with serum (median, 10 pg/ml [range, < 1 to 1221 pg/ml]) (P < 0.0001). IL-6 levels in ascites correlated significantly with the volume of ascites (P < 0.0001) and nearly so with the size of tumor found at initial surgery (P = 0.05). Serum and ascites IL-6 levels did not correlate statistically with overall survival time, tumor stage, grade, histologic findings, residual tumor volume after debulking, and serum CA 125 levels. Although not statistically significant, patients who responded to chemotherapy tended to have lower ascites IL-6 levels (median, 21,102 pg/ml) compared with patients who did not respond to chemotherapy (median, 40,200 pg/ml). CONCLUSIONS: IL-6 is present in very high amounts in the ascites of patients with epithelial ovarian cancer. IL-6 levels in ascites correlated significantly with ascites volume and initial tumor size. IL-6 levels in ascites and serum did not correlate statistically with other tumor parameters or with survival time.

Adult↗
PubMed1994

Reactive oxygen species released by activated neutrophils, but not by deficient spermatozoa, are sufficient to affect normal sperm motility.

OBJECTIVES: To determine whether reactive oxygen species (ROS) produced by abnormal or deficient spermatozoa and polymorphonuclear leukocytes (PMN, activated or not) can affect normal sperm motility. To determine what level of ROS is detrimental to spermatozoa. SUBJECTS: Patients consulting the Infertility Clinic at the Royal Victoria Hospital and healthy volunteers. METHODS: Normal spermatozoa (not producing ROS) were incubated with ROS-producing spermatozoa or PMN (activated or not), and motility was analyzed using a computer-aided sperm analysis system. The proportion of ROS produced by spermatozoa and released extracellularly was estimated by the decrease in the chemiluminescence observed in the presence of catalase and superoxide dismutase. RESULTS: There was no consistent effect on motility when ROS-producing and non-ROS-producing spermatozoa were mixed. This lack of effect could be due to the relatively low level of ROS produced by spermatozoa as well as the fact that only a third of these ROS are released outside spermatozoa. To cause a low but significant decrease (15 +/- 4%) in sperm motility after a 5-hour incubation, the level of ROS imposed on spermatozoa must be equivalent to ROS released by 1 x 10(6) activated PMN/mL. CONCLUSIONS: The production of ROS by deficient spermatozoa is low and of no consequence to the motility of normal spermatozoa present in the same sperm preparation. However, 1 x 10(6) activated PMN/mL, with a 1,000-fold higher ROS production, have detrimental effects on the motility of normal washed spermatozoa.

Extracellular Space↗
PubMed1994

Glucocorticoids, but not dopamine, negatively regulate the melanotrophic activity of the rabbit pituitary intermediate lobe.

The leporidae (rabbit and hare) pituitary intermediate lobe (IL) differs from that of other mammals by its neuroendocrine regulation. In particular, it is not submitted to the classic dopaminergic inhibitory control, which has been considered as a repressive factor for the expression of glucocorticoid receptors (GR) in the mammalian IL. Hence, the present experiments aimed at examining the rabbit IL for the possible existence of GR. Using both immunocytochemistry and binding studies with (3H)-dexamethasone, we localized GR in the nuclei of IL cells and showed the presence of saturable and high-affinity type II receptor sites, with Kd approximately 3.9 nM. Also, exposure of cultured IL cells to 10 nM dexamethasone (DEX) resulted in the blockade of melanocyte-stimulating hormone (alpha MSH) secretion stimulated by oxytocin (OT). Importantly, the inhibitory effect was reversed by a 100-fold excess of the glucocorticoid antagonist RU 38486. This is the first study which clearly demonstrates in a mammalian IL, namely the rabbit, the presence of functional GR, involved in the negative regulation of the melanotrophic activity of this gland.

Animals↗