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Michel Labrecque

Publications and source records attributed to Michel Labrecque.

15 recordsLinked to original sources
PubMed2025

Untargeted metabolomics reveals anion and organ-specific metabolic responses of salinity tolerance in willow.

Willows can alleviate soil salinisation while generating sustainable feedstock for biorefinery, yet the metabolomic adaptations underlying their tolerance remain poorly understood. Salix miyabeana was treated with two environmentally abundant salts, NaCl and Na2SO4, in a 12-week pot trial. Willows tolerated salts across all treatments (up to 9.1 dS m-1 soil ECe), maintaining biomass while selectively partitioning ions, confining Na+ to roots and accumulating Cl- andin the canopy and adapting to osmotic stress via reduced stomatal conductance. Untargeted metabolomics captured >5000 putative compounds, including 278 core willow metabolome compounds constitutively produced across organs. Across all treatments, salinity drove widespread metabolic reprogramming, altering 28% of the overall metabolome, with organ-tailored strategies. Comparing salt forms at equimolar sodium, shared differentially abundant metabolites were limited to 3% of the metabolome, representing the generalised salinity response, predominantly in roots. Anion-specific metabolomic responses were extensive. NaCl reduced carbohydrates and tricarboxylic acid cycle intermediates, suggesting potential carbon and energy resource pressure, and accumulated root structuring compounds, antioxidant flavonoids, and fatty acids. Na2SO4 salinity triggered accumulation of sulphur-containing larger peptides, suggesting excess sulphate incorporation leverages ion toxicity to produce specialised salt-tolerance-associated metabolites. This high-depth picture of the willow metabolome underscores the importance of capturing plant adaptations to salt stress at organ scale and considering ion-specific contributions to soil salinity.

Salix↗
PubMed2006

Frequency and patterns of early recanalization after vasectomy.

BACKGROUND: Our understanding of early post-vasectomy recanalization is limited to histopathological studies. The objective of this study was to estimate the frequency and to describe semen analysis patterns of early recanalization after vasectomy. METHODS: Charts displaying serial post-vasectomy semen analyses were created using the semen analysis results from 826 and 389 men participating in a randomized trial of fascial interposition (FI) and an observational study of cautery, respectively. In the FI trial, participants were randomly allocated to vas occlusion by ligation and excision with or without FI. In the cautery study, sites used their usual cautery occlusion technique, two with and two without FI. Presumed early recanalization was based on the assessment of individual semen analysis charts by three independent reviewers. Discrepancies were resolved by consensus. RESULTS: Presumed early recanalization was characterized by a very low sperm concentration within two weeks after vasectomy followed by return to large numbers of sperm over the next few weeks. The overall proportion of men with presumed early recanalization was 13% (95% CI 12%-15%). The risk was highest with ligation and excision without FI (25%) and lowest for thermal cautery with FI (0%). The highest proportion of presumed early recanalization was observed among men classified as vasectomy failures. CONCLUSION: Early recanalization, occurring within the first weeks after vasectomy, is more common than generally recognized. Its frequency depends on the occlusion technique performed.

Follow-Up Studies↗
PubMed2006

Assessment of needs of men for decision support on male sterilization.

OBJECTIVE: To assess the needs of men for decision support on male sterilization. METHODS: Forty-two men facing a decision about undergoing a vasectomy or not and 11 physicians who perform vasectomy were interviewed to assess the sources of difficulty in this decision-making process. On the day of their vasectomy, 209 men completed the decisional conflict scale (DCS) and a knowledge test. RESULTS: Sources of difficulty about the decision to have a vasectomy or not included: lack of information about risks and benefits, clarification of personal values concerning parenthood after the vasectomy, and undue pressure from partner. On the day of their vasectomy, only 1.9% (95% confidence interval 0.5-4.8%) of men had unresolved decisional conflict. However, most men scored poorly on their knowledge test mean score (58.2+/-13.5%). CONCLUSION: Men facing the decision about having a vasectomy or not would benefit from a decision support intervention that would address conflicting information and clarification of values. PRACTICE IMPLICATIONS: Health professionals should provide decision support to men facing the decision about having a vasectomy or not. A decision aid on male sterilization would be useful in this respect.

Conflict, Psychological↗
PubMed2005

Vasectomy surgical techniques in South and South East Asia.

BACKGROUND: Simple ligation of the vas with suture material and excision of a small vas segment is believed to be the most common vasectomy occlusion technique performed in low-resource settings. Ligation and excision (LE) is associated with a risk of occlusion and contraceptive failure which can be reduced by performing fascial interposition (FI) along with LE. Combining FI with intra luminal thermal cautery could be even more effective. The objective of this study was to determine the surgical vasectomy techniques currently used in five Asian countries and to evaluate the facilitating and limiting factors to introduction and assessment of FI and thermal cautery in these countries. METHODS: Between December 2003 and February 2004, 3 to 6 major vasectomy centers from Cambodia, Thailand, India, Nepal, and Bangladesh were visited and interviews with 5 to 11 key informants in each country were conducted. Vasectomy techniques performed in each center were observed. Vasectomy techniques using hand-held, battery-driven cautery devices and FI were demonstrated and performed under supervision by local providers. Information about interest and open-mindedness regarding the use of thermal cautery and/or FI was gathered. RESULTS: The use of vasectomy was marginal in Thailand and Cambodia. In India, Nepal, and Bangladesh, vasectomy was supported by national reproductive health programs. Most vasectomies were performed using the No-Scalpel Vasectomy (NSV) technique and simple LE. The addition of FI to LE, although largely known, was seldom performed. The main reasons reported were: 1) insufficient surgical skills, 2) time needed to perform the technique, and 3) technique not being mandatory according to country standards. Thermal cautery devices for vasectomy were not available in any selected countries. Pilot hands-on assessment showed that the technique could be safely and effectively performed by Asian providers. However, in addition to provision of supplies, introducing cautery with FI could be associated with the same barriers encountered when introducing FI in combination with LE. CONCLUSION: Further studies assessing the effectiveness, safety, and feasibility of implementation are needed before thermal cautery combined with FI is introduced in Asia on a large scale. Until thermal cautery is introduced in a country, vasectomy providers should practice LE with FI to maximize effectiveness of vasectomy procedure.

Bangladesh↗
PubMed2005

Delayed vasectomy success in men with a first postvasectomy semen analysis showing motile sperm.

OBJECTIVE: To determine the frequency of and factors associated with delayed vasectomy success in men with first postvasectomy semen analysis showing motile sperm. DESIGN: Descriptive study. SETTING: One hospital-based family planning clinic and two private clinics from the Quebec City area, Canada. PATIENT(S): Three hundred nine men vasectomized between 1990 and 2001 and who had a first semen analysis showing motile sperm. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Vasectomy success, based on the last available semen analysis-either in the medical record or as requested for the study-and on sterility as established by a telephone-based questionnaire in 2003. RESULT(S): Among the 309 men, 174 (56.3%, 95% confidence interval 50.7%-61.7%) had delayed vasectomy success. Significant independent factors associated with delayed vasectomy success were lower sperm count in the first postvasectomy semen analysis and shorter interval between vasectomy and first postvasectomy semen analysis. CONCLUSION(S): Delayed vasectomy success occurs in more than half of men with a first postvasectomy semen analysis showing motile sperm. The decision to repeat vasectomy should not rely on a single semen analysis showing motile sperm.

Adult↗
PubMed2005

Prostaglandin E vaginal gel to treat dystocia in spontaneous labour: a multicentre randomised placebo-controlled trial.

OBJECTIVE: To test the safety and efficacy of prostaglandin E(2) (PgE(2)) as a treatment for dystocia in spontaneous labour. DESIGN: Randomised, double-blind, placebo-controlled trial. SETTING: Multicentre study in nine university-affiliated hospitals in Canada. Population Three hundred and thiry-two nulliparous women with spontaneous labour at term. METHODS: Women who had progressed < 2 cm of cervical dilation in the 4 hours following the diagnosis of labour were randomly assigned to receive a single dose of either 1 mg (n= 112) or 2 mg (n= 111) PgE(2) vaginal gel or placebo gel (n= 109). MAIN OUTCOME MEASURES: The primary outcome was resolution of dystocia, defined as a change in cervical dilatation of >0.5 cm per hour in the 6 hours following gel administration. Secondary outcomes were progress of labour, uterine hyperstimulation (more than five contractions in 10 minutes or a contraction lasting more than 2 minutes), use of oxytocin, method of delivery, maternal and neonatal morbidity. RESULTS: Dystocia resolved more often after PgE(2) 1 mg (49%), RR 1.53 (95% CI 1.1, 2.1) and PgE(2) 2 mg (49%), RR 1.5 (CI 1.1, 2.1), compared with placebo (32%). Hyperstimulation was increased after PgE(2) 2 mg treatment (15%), RR 5.6 (95% CI 1.7, 18), but not after PgE(2) 1 mg (5.4%), RR 1.9 (CI 0.50, 7.6) when compared with placebo (2.8%). There was an increase in caesarean sections performed in the second stage of labour in the PgE(2) groups versus placebo. There were no differences in measures of maternal or neonatal morbidity. CONCLUSION: A single 1-mg dose of PgE(2) vaginal gel is more effective than placebo in resolving dystocia, without increasing uterine hyperstimulation, but may be associated with an increase in the incidence of second stage caesarean section.

Adult↗
PubMed2004

A comparison of vas occlusion techniques: cautery more effective than ligation and excision with fascial interposition.

BACKGROUND: Vasectomy techniques have been the subject of relatively few rigorous studies. The objective of this analysis was to compare the effectiveness of two techniques for vas occlusion: intraluminal cautery versus ligation and excision with fascial interposition. More specifically, we aimed to compare early failure rates, sperm concentrations, and time to success between the two techniques. METHODS: We compared semen analysis data from men following vasectomy using two occlusion techniques. Data on intraluminal cautery came from a prospective observational study conducted at four sites. Data on ligation and excision with fascial interposition came from a multicenter randomized controlled trial that evaluated the efficacy of ligation and excision with versus without fascial interposition. The surgical techniques used in the fascial interposition study were standardized. The surgeons in the cautery study used their customary techniques, which varied among sites in terms of type of cautery, use of fascial interposition, excision of a short segment of the vas, and use of an open-ended technique. Men in both studies had semen analyses two weeks after vasectomy and then approximately every four weeks. The two outcome measures for the analyses presented here are (a) time to success, defined as severe oligozoospermia, or <100,000 sperm/mL in two consecutive semen analyses; and (b) early vasectomy failure, defined as >10 million sperm/mL at week 12 or later. RESULTS: Vasectomy with cautery was associated with a significantly more rapid progression to severe oligozoospermia and with significantly fewer early failures (1% versus 5%). CONCLUSION: The use of cautery improves vasectomy outcomes. Limitations of this comparison include (a) the variety of surgical techniques in the cautery study and differences in methods of fascial interposition between the two studies, (b) the uncertain correlation between sperm concentrations after vasectomy and the risk of pregnancy, and (c) the use of historical controls and different study sites.

Cautery↗
PubMed2004

Vasectomy surgical techniques: a systematic review.

BACKGROUND: A wide variety of surgical techniques are used to perform vasectomy. The purpose of this systematic review was to assess if any surgical techniques to isolate or occlude the vas are associated with better outcomes in terms of occlusive and contraceptive effectiveness, and complications. METHODS: We searched MEDLINE (1966-June 2003), EMBASE (1980-June 2003), reference lists of retrieved articles, urology textbooks, and our own files looking for studies comparing two or more vasectomy surgical techniques and reporting on effectiveness and complications. From 2,058 titles or abstracts, two independent reviewers identified 224 as potentially relevant. Full reports of 219 articles were retrieved and final selection was made by the same two independent reviewers using the same criteria as for the initial selection. Discrepancies were resolved by involving a third reviewer. Data were extracted and methodological quality of selected studies was assessed by two independent reviewers. Studies were divided in broad categories (isolation, occlusion, and combined isolation and occlusion techniques) and sub-categories of specific surgical techniques performed. Qualitative analyses and syntheses were done. RESULTS: Of 31 comparative studies (37 articles), only four were randomized clinical trials, most studies were observational and retrospective. Overall methodological quality was low. From nine studies on vas isolation, there is good evidence that the no-scalpel vasectomy approach decreases the risk of surgical complications, namely hematoma/bleeding and infection, compared with incisional techniques. Five comparative studies including one high quality randomized clinical trial provided good evidence that fascial interposition (FI) increases the occlusive effectiveness of ligation and excision. Results of 11 comparative studies suggest that FI with cautery of the vas lumen provides the highest level of occlusive effectiveness, even when leaving the testicular end open. Otherwise, firm evidence to support any occlusion technique in terms of increased effectiveness or decreased risk of complications is lacking. CONCLUSIONS: Current evidence supports no-scalpel vasectomy as the safest surgical approach to isolate the vas when performing vasectomy. Adding FI increases effectiveness beyond ligation and excision alone. Occlusive effectiveness appears to be further improved by combining FI with cautery. Methodologically sound prospective controlled studies should be conducted to evaluate specific occlusion techniques further.

Humans↗
PubMed2004

Effects of carrying a pregnancy and of method of delivery on urinary incontinence: a prospective cohort study.

BACKGROUND: This study was carried out to identify risk factors associated with urinary incontinence in women three months after giving birth. METHODS: Urinary incontinence before and during pregnancy was assessed at study enrolment early in the third trimester. Incontinence was re-assessed three months postpartum. Logistic regression analysis was used to assess the role of maternal and obstetric factors in causing postpartum urinary incontinence. This prospective cohort study in 949 pregnant women in Quebec, Canada was nested within a randomised controlled trial of prenatal perineal massage. RESULTS: Postpartum urinary incontinence was increased with prepregnancy incontinence (adjusted odds ratio [adj0R] 6.44, 95% CI 4.15, 9.98), incontinence beginning during pregnancy (adjOR 1.93, 95% CI 1.32, 2.83), and higher prepregnancy body mass index (adjOR 1.07/unit of BMI, 95% CI 1.03,1.11). Caesarean section was highly protective (adjOR 0.27, 95% CI 0.14, 0.50). While there was a trend towards increasing incontinence with forceps delivery (adjOR 1.73, 95% CI 0.96, 3.13) this was not statistically significant. The weight of the baby, episiotomy, the length of the second stage of labour, and epidural analgesia were not predictive of urinary incontinence. Nor was prenatal perineal massage, the randomised controlled trial intervention. When the analysis was limited to women having their first vaginal birth, the same risk factors were important, with similar adjusted odds ratios. CONCLUSIONS: Urinary incontinence during pregnancy is extremely common, affecting over half of pregnant women. Urinary incontinence beginning during pregnancy roughly doubles the likelihood of urinary incontinence at 3 months postpartum, regardless whether delivery is vaginal or by Caesarean section.

Journal Article↗
PubMed2003

Association between the length of the vas deferens excised during vasectomy and the risk of postvasectomy recanalization.

OBJECTIVE: To evaluate the association between the length of the vas deferens excised during vasectomy and the risk of recanalization. DESIGN: Nested case-control study. SETTING: Hospital-based Family Planning Clinic in Quebec City (Canada). PATIENT(S): Among 870 vasectomized men, all 47 cases of spontaneous recanalization and 188 controls whose first semen analysis showed either azoospermia (controls A) or <1 x 10(6)/mL nonmotile sperm (controls B). MAIN OUTCOME MEASURE(S): Spontaneous recanalization defined as a semen analysis showing any motile sperm 6 weeks or more after vasectomy. RESULT(S): Individual vas segments excised ranged from 5 to 20 mm in 227 (97%) of the 235 participants. The mean +/- SD of the average of both segments for each man was 12 +/- 4 mm, identical in cases and in controls. In cases and controls A, the risk ratio (95% confidence interval [CI]) of recanalization with an average of segments of <10 mm and 10-14 mm was 0.6 (0.1-2.0) and 0.6 (0.2-1.6) when compared to 15 mm or more, respectively. In cases vs. controls B, the risk ratio of recanalization was 1.6 (0.4-7.7) and 0.6 (0.2-1.7), respectively. CONCLUSION(S): In this cohort, there was no association between the length of vas segment excised and the risk of recanalization.

Adult↗
PubMed2002

Anal incontinence after childbirth.

BACKGROUND: Incontinence of stool and flatus are frequent complications of childbirth. We examined the prevalence and possible causes of these adverse outcomes in a large cohort of women. METHODS: We studied 949 pregnant women who gave birth in 5 hospitals in 1995/96 in the province of Quebec. These women, participants in a randomized controlled trial of prenatal perineal massage, completed a self-administered questionnaire 3 months after giving birth. RESULTS: Three months after delivery 29 women (3.1%) reported incontinence of stool, and 242 (25.5%) had involuntary escape of flatus. Incontinence of stool was more frequent among women who delivered vaginally and had third- or fourth-degree perineal tears than among those who delivered vaginally and had no anal sphincter tears (7.8% v. 2.9%). Forceps delivery (adjusted risk ratio [RR] 1.45, 95% confidence interval [CI] 1.01-2.08) and anal sphincter tears (adjusted RR 2.09, 95% CI 1.40-3.13) were independent risk factors for incontinence of flatus or stool or both. Anal sphincter injury was strongly and independently associated with first vaginal birth (RR 39.2, 95% CI 5.4-282.5), median episiotomy (adjusted RR 9.6, 95% CI 3.2-28.5), forceps delivery (adjusted RR 12.3, 95% CI 3.0-50.4) and vacuum-assisted delivery (adjusted RR 7.4, 95% CI 1.9-28.5) but not with birth weight (adjusted RR for nirth weight 4000 g or more: 1.4, 95% CI 0.6-3.0) or length of the second stage of labour (adjusted RR for second stage 1.5 hours or longer compared with less than 0.5 hours: 1.2, 95% CI 0.5-2.7). INTERPRETATION: Anal incontinence is associated with forceps delivery and anal sphincter laceration. Anal sphincter laceration is strongly predicted by first vaginal birth, median episiotomy, and forceps or vacuum delivery but not by birth weight or length of the second stage of labour.

Anal Canal↗
PubMed2002

Effectiveness and complications associated with 2 vasectomy occlusion techniques.

PURPOSE: We compared the effectiveness and complications associated with 2 common vasectomy occlusion techniques, namely clipping and excision of a small vas segment and thermal cautery with fascial interposition and an open testicular end. MATERIALS AND METHODS: We retrospectively reviewed the computerized records of 3,761 men who underwent initial vasectomy at a single university hospital family planning clinic and at 2 private clinics in the Quebec City, Canada area, including concurrent and historical controls. All procedures were performed by 1 surgeon, who used the scalpel-free technique to expose the vas. RESULTS: The risk of vas occlusion failure in men with at least 1 semen analysis was much greater in the clipping and excision group than in the cautery, interposition and open testicular end group (126 of 1,453 or 8.7% versus 3 of 1,165 or 0.3%, OR 37, 95% CI 12 to 116). Medical consultations for hematoma or infection were more frequent in the cautery group (28 of 1,721 cases or 1.6% versus 10 of 2,040 or 0.5%, OR 3.4, 95% CI 1.6 to 6.9). Consultations for noninfectious pain were similar for the 2 techniques (71 of 1,721 cases or 4.1% versus 72 of 2,040 or 3.5%, OR 1.2, 95% CI 0.8 to 1.6). CONCLUSIONS: Cautery and interposition with an open testicular end are much more effective than clipping and excision. The effectiveness and morbidity associated with the components of the cautery, interposition and open testicular end technique need further evaluation.

Cautery↗