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Robert Cohen

Publications and source records attributed to Robert Cohen.

At least 19 recordsLinked to original sources
PubMed2026

Prevalence and risk factors for persistent faecal carriage of extended spectrum beta-lactamase producing Escherichia coli in a paediatric community population.

OBJECTIVE: To investigate clinical and microbiological factors associated with persistent faecal carriage of extended spectrum beta-lactamase (ESBL) producing Escherichia coli in infants. METHODS: Between 2010 and 2022, children aged 3 months to 2 years old were sampled in a community setting in France, at two visits, V1 and V2, 3-24 months apart, to screen for prolonged faecal carriage of ESBL-producing E. coli. Patient clinical information and whole genome sequence of each isolate were used for association studies. RESULTS: A total of 4641 children were sampled. 375 (8%) carried an ESBL-producing Enterobacterales, among which 142 of ESBL-producing E. coli carriers were once again sampled at V2 and included in this study. 21.8% (n = 31/142) and 18.4% (n = 16/99) carried the same ESBL-producing E. coli clone for at least 3 and 6 months, respectively. B2 phylogroup, and among which ST131 clones were associated with an increased risk of persistent carriage. Multivariate analysis identified virulence associated genes involved in adhesion (papC/papGII allele and a tia-like gene) and encoding toxin (senB) as major risk factors for persistence. A genome wide association study highlighted the potential role of the frz metabolic operon, known to be involved in enterocytes adhesion/internalisation. CONCLUSION: Main extraintestinal pathogenic E. coli genomic features (phylogenetic background, adhesion properties) are associated with ESBL-producing E. coli gut colonisation persistence in infants, which could potentially lead to an increased risk of febrile urinary tract infection in these patients.

Child↗
PubMed2005

Bacterial meningitis in children: a French prospective study.

From January 2001 through December 2003, a total of 1084 children with bacterial meningitis were enrolled in a prospective French nationwide survey. The most frequent pathogens found in children older than 28 days were Neisseria meningitis (55.3%) and Streptococcus pneumoniae (33.4%). S. pneumoniae was the most frequent pathogen found among infants aged 2-12 months (49.5%), whereas N. meningitidis was the most frequent pathogen among children >12 months old (69.7%). Approximately one-half of S. pneumoniae isolates had diminished susceptibility to penicillin. The case-fatality rates were 7.6% for children with N. meningitidis meningitis and 10.8% for children with S. pneumoniae infection.

Adolescent↗
PubMed2005

Ability of primary care physician's to break bad news: a performance based assessment of an educational intervention.

OBJECTIVE: We have previously described a breaking bad news (BBN) training program for primary care physicians [Ungar L, Alperin M, Amiel GE, Beharier Z, Reis S. Breaking bad news: structured training for family medicine residents. Patient Educ Couns 2002;48:63-68]. In this paper, we present the assessment of an educational intervention aimed at improving this important skill. METHODS: The assessment tool was an eight station objective structured clinical examination (OSCE) utilizing standardized patients (SPs). Intervention and control groups of 17 general practitioners (GP) each were evaluated before and after an educational intervention, or a Balint group (control). RESULTS: Intervention group GPs significantly increased their average grade on the post-test as compared to the pre-test (58.5, S.D. 12.7 versus 68.4, S.D. 9.2), effect size 0.94. Improvement in the control group was minimal (pre-test 57, S.D. 10.4 versus 58.1, S.D. 9.5 for the post-test), effect size 0.23. Reliability of the OSCE was alpha = 0.81. CONCLUSION: The performance assessment used in this study proved to be a reliable and valid tool to assess the ability of physicians to break bad news. It provided evidence of the effectiveness of the intervention. PRACTICE IMPLICATIONS: BBN training can and should be evaluated by valid and reliable measures. SPs can serve as reliable evaluators of BBN training.

Adult↗
PubMed2005

A randomized trial of teaching bioethics to surgical residents.

BACKGROUND: Bioethics education has been recommended as a formal component of surgical residency training. The best method for teaching bioethics to residents is unclear. We compared the effectiveness of a standardized patient (SP)-based seminar to a traditional seminar format for teaching bioethics to surgical residents. METHODS: We randomized 31 first- and second-year surgical residents to either a SP-based seminar or a traditional seminar on informed consent. Immediately after the seminars, we evaluated resident performance in patient encounters on informed consent by using an objective structured clinical examination. Their knowledge of informed consent was also evaluated by using a 20-question short-answer written examination immediately after the seminars and then 3 weeks later. RESULTS: Twenty-nine residents completed the study; two withdrew because of an emergency. The SP seminar group had lower SP interview scores on the 22 item checklist compared with the traditional seminar group (57% versus 66%; difference -9%; 95% confidence interval [CI], -17% to -1%, P=.03). The SP seminar group also had lower knowledge scores on the questionnaire immediately after the seminar (60% versus 73%; difference -13%; 95% CI, -21% to -4%, P=.003). The difference in knowledge scores persisted at 3 weeks (41% for the SP group, 59% for the traditional seminar group; difference -18%; 95% CI, -29% to -7%; P=.002). CONCLUSIONS: A traditional seminar was superior to an SP-based seminar for teaching informed consent to surgical residents.

Adult↗
PubMed2005

The Otto Aufranc Award: bone augmentation around and within porous implants by local bisphosphonate elution.

The bisphosphonate zoledronic acid chemically and physically was bound to hydroxyapatite-coated porous tantalum implants. The zoledronic acid elution characteristics in saline were determined as a function of time and the in vivo effects of elution were quantified at 12 weeks in a canine ulnar implant model. Intramedullary implants surgically were implanted bilaterally into the ulnae of a control group of five dogs and a zoledronic acid-dosed (0.05 mg zoledronic acid) group of four dogs. Computerized image analysis of undecalcified histologic sections was used to quantify the amount of peri-implant bone within the intramedullary canal, the percentage of available pore space filled with new bone, and the number and size of the individual bone islands within the implant pores. The data were analyzed using a hierarchical analysis of variance with 95% confidence intervals. The peri-implant bone occupied a mean of 13.8% of the canal space in controls and 32.2% of the canal space in zoledronic acid-dosed dogs, a relative difference of 134% (2.34-fold) that was significant. The mean extent of bone ingrowth was 12.5% for the control implants and 19.8% for the zoledronic acid-dosed dogs, a relative difference of 58% that was statistically significant. Individual islands of new bone formation with the implant pores were similar in number in both implant groups but were 71% larger on average in the ZA-dosed group. We are the first authors to show that local elution of a bisphosphonate can cause substantial bone augmentation around and within porous orthopaedic implants. The concept represents a potential tool for restoration of bone stock and enhancement of implant fixation in primary and revision cementless joint arthroplasty surgeries in the face of compromised or deficient bone.

Animals↗
PubMed2005

Epidemiologic study of conjunctivitis-otitis syndrome.

We conducted a prospective cross-sectional epidemiologic study of conjunctivitis-otitis syndrome during two 3-week periods of consecutive winters. A representative sample of 184 pediatricians and ear, nose and throat specialists in the Paris area recruited 2901 children from 6 to 36 months of age presenting with acute otitis media, of whom 465 (16%) also had purulent conjunctivitis. In sampled children, the culture of the conjunctival exudate yielded bacterial pathogens in 419 patients: Haemophilus influenzae, 371 (89%); Streptococcus pneumoniae, 72 (17%); and Branhamella catarrhalis, 23 (5%). Pulsed field gel electrophoresis analysis of paired H. influenzae isolates from the conjunctival exudate and middle ear fluid of 21 patients showed identical strains in each patient.

Child, Preschool↗
PubMed2005

Treatment of chronic hepatitis C virus infection via antioxidants: results of a phase I clinical trial.

BACKGROUND: The pathogenesis of chronic hepatitis C virus (HCV) infection is associated with a defective host antiviral immune response and intrahepatic oxidative stress. Oxidative stress and lipid peroxidation play major roles in the fatty liver accumulation (steatosis) that leads to necro-inflammation and necrosis of hepatic cells. Previous trials suggested that antioxidative therapy may have a beneficial effect on patients with chronic HCV infection. AIMS: To determine the safety and efficacy of treatment of chronic HCV patients via a combination of antioxidants. METHODS: Fifty chronic HCV patients were treated orally on a daily basis for 20 weeks with seven antioxidative oral preparations (glycyrrhizin, schisandra, silymarin, ascorbic acid, lipoic acid, L-glutathione, and alpha-tocopherol), along with four different intravenous preparations (glycyrrhizin, ascorbic acid, L-glutathione, B-complex) twice weekly for the first 10 weeks, and followed up for an additional 20 weeks. Patients were monitored for HCV-RNA levels, liver enzymes, and liver histology. Assessment of quality of life was performed using the SF-36 questionnaire. RESULTS: In one of the tested parameters (eg, liver enzymes, HCV RNA levels, or liver biopsy score), a combination of antioxidants induced a favorable response in 48% of the patients (24). Normalization of liver enzymes occurred in 44% of patients who had elevated pretreatment ALT levels (15 of 34). ALT levels remained normal throughout follow-up period in 72.7% (8 of 11). A decrease in viral load (one log or more) was observed in 25% of the patients (12). Histologic improvement (2-point reduction in the HAI score) was noted in 36.1% of the patients. The SF-36 score improved in 26 of 45 patients throughout the course of the trial (58% of the patients). Treatment was well tolerated by all patients. No major adverse reactions were noted. CONCLUSIONS: These data suggest that multi antioxidative treatment in chronic HCV patients is well tolerated and may have a beneficial effect on necro-inflammatory variables. A combination of antiviral and antioxidative therapies may enhance the overall response rate of these patients.

Adolescent↗
PubMed2005

A new measure of children's optimism and pessimism: the youth life orientation test.

BACKGROUND: Optimism and pessimism are positive and negative expectations linked with well-being in adults. Research on the importance of optimism and pessimism in children is limited by the lack of a developmentally appropriate measure of children's expectations. METHOD: Based upon the Life Orientation Test-Revised (Scheier, Carver, & Bridges, 1994), the Youth Life Orientation Test (YLOT) is a sixteen-item self-report measure of children's optimism and pessimism. RESULTS: Reliability and validity of the YLOT was found with 204 3rd-6th graders. Optimism also predicted fewer child-reported depressive symptoms and parent-reported behavior problems assessed three months later. Pessimism predicted more child-reported anxiety symptoms and parent-reported social and academic deficits.

Adaptation, Psychological↗
PubMed2004

Activity of telithromycin and comparators against bacterial pathogens isolated from 1,336 patients with clinically diagnosed acute sinusitis.

BACKGROUND: Increasing antimicrobial resistance among the key pathogens responsible for community-acquired respiratory tract infections has the potential to limit the effectiveness of antibiotics available to treat these infections. Since there are regional differences in the susceptibility patterns observed and treatment is frequently empirical, the selection of antibiotic therapy may be challenging. PROTEKT, a global, longitudinal multicentre surveillance study, tracks the activity of telithromycin and comparator antibacterial agents against key respiratory tract pathogens. METHODS: In this analysis, we examine the prevalence of antibacterial resistance in 1,336 bacterial pathogens, isolated from adult and paediatric patients clinically diagnosed with acute bacterial sinusitis (ABS). RESULTS AND DISCUSSION: In total, 58.0%, 66.1%, and 55.8% of S. pneumoniae isolates were susceptible to penicillin, cefuroxime, and clarithromycin respectively. Combined macrolide resistance and reduced susceptibility to penicillin was present in 200/640 (31.3 %) of S. pneumoniae isolates (128 isolates were resistant to penicillin [MIC > or = 2 mg/L], 72 intermediate [MIC 0.12-1 mg/L]) while 99.5% and 95.5% of isolates were susceptible to telithromycin and amoxicillin-clavulanate, respectively. In total, 88.2%, 87.5%, 99.4%, 100%, and 100% of H. influenzae isolates were susceptible to ampicillin, clarithromycin, cefuroxime, telithromycin, and amoxicillin-clavulanate, respectively. In vitro, telithromycin demonstrated the highest activity against M. catarrhalis (MIC50 = 0.06 mg/L, MIC90 = 0.12 mg/L). CONCLUSION: The high in vitro activity of against pathogens commonly isolated in ABS, together with a once daily dosing regimen and clinical efficacy with 5-day course of therapy, suggest that telithromycin may play a role in the empiric treatment of ABS.

Journal Article↗
PubMed2004

Context-specific memory and apolipoprotein E (ApoE) epsilon 4: cognitive evidence from the NIMH prospective study of risk for Alzheimer's disease.

The aim of the study was to determine whether the epsilon 4 allele of the apolipoprotein E (ApoE) gene was associated primarily with context-specific memory among individuals at genetic risk for developing Alzheimer's disease. The effect of ApoE status on comprehensive neuropsychological results was examined in 176 healthy adults during baseline cognitive testing in the NIMH Prospective Study of Biomarkers for Older Controls at Risk for Alzheimer's Disease (NIMH Prospective BIOCARD Study). The presence of the epsilon 4 allele was associated with significantly lower total scores on the Logical Memory II subtest of the Wechsler Memory Scale-Revised and percent of information retained after delay. Further analysis indicated the prose recall and retention effect was partially explained by a small subgroup of epsilon 4 homozygotes, suggesting a gradually progressive process that may be presaged with specific cognitive measures. The current results may represent an epsilon 4-associated breakdown between gist-related information and context-bound veridical recall. This relative disconnection may be understood in light of putative epsilon 4-related preclinical accumulation of Alzheimer pathology (tangles and plaques) in the entorhinal cortex (EC) and among frontal networks, as well as the possibility of less-efficient compensatory strategies.

Adult↗
PubMed2004

Defining the optimum treatment regimen for azithromycin in acute tonsillopharyngitis.

Pharyngitis is one of the most common infectious diseases affecting children. Group A streptococci are the leading bacterial cause of pharyngitis in children and adults. Because inappropriate antibiotic treatment for pharyngitis is becoming a major issue, only true group A beta-hemolytic streptococcus (GABHS) infections, proven by rapid antigen test or culture, should be treated with antibiotics. GABHS pharyngitis is often a mild and self-limiting infection in the absence of antimicrobial therapy. However, antimicrobial treatment must be administered to eradicate the pathogen from the throat, limit the spread of the infection and prevent possible progression to rheumatic fever, suppurative disease or toxin-mediated complications. Penicillin V for 10 days is the standard therapy and is effective in the management of GABHS pharyngitis. However, there are drawbacks to penicillin V therapy, including the length of the dosing regimen, which are leading to decreasing penicillin prescription rates in many countries. In addition bacteriologic treatment failures have been documented in up to 35% of GABHS patients treated with penicillin V, particularly in children <6 years old. A number of mechanisms may be responsible for these failures, but poor compliance with the standard 10-day penicillin treatment is likely to be a major factor. There is growing evidence to suggest that children with GABHS pharyngitis can be effectively treated with non-penicillin V antibiotics, which have the advantage of simpler and shorter dosing regimens compared with penicillin V. Among the antibiotics that have been tested clinically, azithromycin is the most widely studied. A total dose of 60 mg/kg azithromycin, given either as 12 mg/kg once daily for 5 days or 20 mg/kg once daily for 3 days, provides the best rate of GABHS eradication. Thus a total dose of 60 mg/kg azithromycin given during 3 or 5 days constitutes an alternative treatment to standard penicillin therapy in cases of penicillin hypersensitivity, when patient nonadherence to a 10-day penicillin regimen is suspected or for patients who fail therapy with a beta-lactam.

Azithromycin↗
PubMed2004

Role of nitric oxide in skin flap delay.

Surgical delay of skin flaps before transfer is known to improve flap viability. This study attempts to elucidate the mechanism of vasodilation by exploring the effects of nitric oxide on the microcirculation of delayed skin flaps. Using a skin flap model in 22 CD-1 white mice, the diameter of two nonterminal choke arteries was measured using in vivo videomicroscopy. Vessel flow was also measured using an optical Doppler velocimeter. Similar measurements were recorded in several animals on the same vessels in which subcutaneous dissection without elevation was performed. Average vessel diameter ranged from 21.77 to 25.55 microm before skin flap delay. Average flow ranged from 1.72 to 2.44 nl/sec before delay. Next, each animal received an intraperitoneal dose of nitro-aminomethyl-1-arginine (L-NAME), a nitric oxide synthase inhibitor delivered by means of osmotic pump at a level of 0 (n = 13 arteries), 20 (n = 10), 50 (n = 8), or 100 mg/kg/day (n = 7). Flaps were re-elevated 72 hours later and the aforementioned measurements were repeated. Vessel diameter increased to 44.92 microm in the control (0 mg/kg L-NAME) animals. Flow increased to 7.66 nl/sec in the control animals. Vessel dilation and flow did not change significantly in the nonoperative vessels. As the dose of L-NAME increased in the treated animals, there was a significant decrease in vasodilation and flow (p = 0.015 and p = 0.03, respectively). The authors' results demonstrate that nitric oxide is an important element of vasodilation and contributor to the phenomenon of skin flap delay.

Animals↗