Publications by authors named "Lamothe F"

Attributing individual deaths to extreme heat events (EHE) in Canada and elsewhere is important for understanding the risk factors, protective interventions, and burden of mortality associated with climate change. However, there is currently no single mechanism for identifying individual deaths due to EHE and different agencies have taken different approaches, including (1) vital statistics coding based on medical certificates of death, (2) probabilistic methods, and (3) enhanced surveillance. The 2018 EHE in Montréal provides an excellent case study to compare EHE deaths identified by these different approaches.

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Warfarin is primarily metabolized by cytochrome 2C9, encoded by gene CYP2C9. Here, we investigated whether variants in nuclear receptor genes which regulate the expression of CYP2C9 are associated with warfarin response. We used data from 906 warfarin users from the Quebec Warfarin Cohort (QWC) and tested the association of warfarin dose requirement at 3 months following the initiation of therapy in nine nuclear receptor genes: NR1I3, NR1I2, NR3C1, ESR1, GATA4, RXRA, VDR, CEBPA, and HNF4A.

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Article Synopsis
  • The incidence of dengue virus (DENV) has surged globally, becoming endemic in over 100 countries.
  • DENV employs various strategies to evade the host's innate immune responses, particularly targeting the type I interferon system.
  • The DENV NS2B protease cofactor promotes the degradation of the DNA sensor cGAS, preventing it from detecting mitochondrial DNA and thereby inhibiting type I interferon production in infected cells.
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Bacteremia due to Cloacibacillus species is poorly described. We present three cases involving either Cloacibacillus evryensis or Cloacibacillus porcorum. The isolates were identified by 16S rRNA gene sequencing and were susceptible to antibiotics commonly used for anaerobic infections.

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Background: Clostridium difficile (CD) is the leading cause of health care-associated diarrhea and can result in asymptomatic carriage. Rates of asymptomatic CD colonization on hospital admission range from 1.4%-21%.

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Background: Clostridium difficile infection is the leading cause of health care-associated diarrhea, and the bacterium can also be carried asymptomatically. The objective of this study was to identify host and bacterial factors associated with health care-associated acquisition of C. difficile infection and colonization.

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The authors sought to investigate trends in the incidence of human immunodeficiency virus (HIV) infection, evaluate changes in risk behavior, and assess associations between syringe access programs and HIV seroconversion among injection drug users (IDUs) in Montreal, Canada, who were recruited and followed for a prospective cohort study between 1992 and 2008. Methods included Kaplan-Meier survival analysis and time-varying Cox regression models. Of 2,137 HIV-seronegative IDUs at enrollment, 148 became HIV-positive within 4 years (incidence: 3.

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Clostridium difficile isolates from a 2004 outbreak in Québec, Canada, were all found to be susceptible to metronidazole, vancomycin, rifampin, and meropenem but resistant to bacitracin, cefotaxime, ciprofloxacin, and levofloxacin, and most (>80%) were resistant to ceftriaxone, clarithromycin, gatifloxacin, and moxifloxacin. The predominant NAP1 isolates were susceptible to clindamycin, while the NAP2 isolates were resistant.

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Objective: The main goal of this study was to construct a prognostic model for HIV seroconversion among injection drug users (IDUs) using easy-to-measure risk indicators.

Design: Cox proportional hazards regression modeling was used for risk stratification in a heterogeneous population of IDUs with regards to HIV risk-taking behaviors.

Methods: Subjects were recruited in a prospective cohort of IDUs followed between September 1992 and October 2001.

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Objective: To assess the influence of route of HIV exposure on the development of HIV-specific CD8 T-cell responses in exposed, uninfected (EU) individuals.

Design: Two groups of EU exposed to virus through either sexual or intravenous contact were studied. Group I included subjects (n = 20) who had unprotected sexual contact with known HIV-infected partners and no intravenous HIV exposure; Group II included individuals (n = 27) who had shared needles with HIV-infected partners and had no sexual exposure to this virus.

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Aims: The objective of this study was to identify factors associated with sustained injection cessation and to examine further the relationship between the occurrence of sustained injection cessation of injection drug users (IDUs) and prior injection frequency.

Design And Setting: IDUs in the Montreal St Luc Cohort who had at least three consecutive interviews between 1995 and 1999 were included. Sustained injection cessation was defined as a period of at least 7 consecutive months without injection.

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In Canada, very little is known about the factors and processes that cause drug-related harm among female intravenous drug users (IDUs). Women who inject drugs and participate in the survival sex trade are considered to be at increased risk for sexual and drug-related harms, including HIV infection. Between September 1999 and September 2000, women participating in the VIDUS cohort in Vancouver and the St.

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Objectives: To determine whether HIV-exposed, uninfected subjects (EUs) having HIV-specific effector activity are at a reduced risk for seroconverting compared with EUs with no HIV-specific effector responses.

Design: Twenty-eight intravenous drug users (IVDU) with documented risk for HIV infection over a 1-year period were screened for the presence of HIV-specific CD8+ effector cell activity. Group I included 18 IVDUs who remained seronegative despite exposure to HIV through needle sharing with partner(s) known to be HIV infected.

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This study examined the effect of an HIV-positive notification on the sexual and injection behaviors, living conditions, and medical demands of injection drug users (IDUs) in Montreal. The behavior changes of 73 IDUs who received an HIV-positive test result, and 219 IDUs who tested negative were compared, and the net difference (ND) in the proportion of IDUs adopting the particular change was determined. No significant changes were found in drug use or needle sharing practices.

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OBJECTIVE: To determine the frequency with which Clostridium difficile was detected in stool specimens from outpatients and patients hospitalized for less than 4 days to assess the usefulness of routine laboratory screening for detecting this enteric pathogen. METHODS: Seven hundred and forty-one specimens from 398 patients were cultured over a 6-month period for Salmonella, Shigella, Yersinia, Escherichia coli O157:H7, Campylobacter and Clostridium difficile. Clostridium difficile culture-positive samples were further tested for cytotoxin production.

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Background: Sex-specific issues have not been extensively addressed in studies of HIV prevalence, despite the strong implications of differences between men and women in the risk of HIV transmission. The objective of this study was to examine sex-specific behaviours associated with HIV infection among injection drug users in Montreal.

Methods: A total of 2741 active drug users (2209 [80.

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In the province of Quebec, Canada, from 1996 to 1998, 3,650 invasive Streptococcus pneumoniae infections were reported. A total of 1,354 isolates were serotyped and tested for antimicrobial susceptibility. The distribution of serotypes remained stable over the 3 years, with serotypes 14, 6B, 4, 9V, 23F, and 19F accounting for 61% of the isolates.

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Objective: To investigate the independent association between changes in risk behaviour and HIV seroconversion risk among Montreal injection drug users (IDU).

Design: A longitudinal study of risk behaviour change and the maintenance of low-risk practices. At baseline and semi-annually, subjects were tested for HIV, and questionnaires on risk behaviour were completed.

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The objective of the present study was to analyze the susceptibility profiles of 911 clinical strains of the Bacteroides fragilis group isolated from 1992 to 1997 in our institution in order to monitor susceptibility changes over time. Whereas the rates of resistance to metronidazole, imipenem, piperacillin-tazobactam, ticarcillin-clavulanic acid, penicillin, piperacillin, and cefoxitin remained essentially unchanged, there was a significant increase in the rates of resistance to clindamycin, which rose from 8.2% in 1992 to 19.

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Needle exchange programs (NEPs) are designed to prevent human immunodeficiency virus (HIV) transmission among injection drug users. Although most studies report beneficial effects in terms of behavior modification, a direct assessment of the effectiveness of NEPs in preventing HIV infection has been lacking. A cohort study was conducted to assess the association between risk behaviors and HIV seroprevalence and seroincidence among injection drug users in Montreal, Canada.

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During the past 15 years, important contributions have been made to the field of anaerobes in Canada. Studies on the importance of the intestinal flora as a source of vitamin K for humans, investigations of the mechanisms of synergy in polymicrobial infections, and extensive research on the field of immunocompetence of surgical patients have provided interesting and valuable information. Several clinical and epidemiological studies of anaerobic infections have been carried out.

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A retrospective study was conducted to assess the relationships between clindamycin resistance in members of the Bacteroides fragilis group, previous antimicrobial therapy, and the context for the development of infection, whether in the community or during hospitalization. Eighty-five clindamycin-resistant clinical strains (one isolate per patient) isolated from January 1988 to October 1994 were matched (one to one) with clindamycin-susceptible isolates recovered during the same period, and the charts of the patients from whom the isolates were recovered were reviewed retrospectively. Of the clindamycin-resistant strains, 65% were recovered from patients with hospital-acquired infections compared with 40% of the clindamycin-susceptible strains (odds ratio [OR], 2.

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A study sample of 7,010 episodes of invasive Streptococcus pneumoniae disease was obtained by combining 13 existing datasets. Disease episodes due to each of 12 pneumococcal serogroups (1, 3-9, 14, 18, 19, and 23) were then compared with episodes in a constant internal control group to describe serogroup-specific variations in disease frequency by age, sex, and geographic origin. The results are presented as odds ratios (with 95% confidence intervals) derived by logistic regression, with adjustment for the major confounders, including dataset of origin.

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