Biomedical subjects

Robert Cohen

Publications and source records attributed to Robert Cohen.

46 records · Page 3Linked to original sources

PubMed2002

Update on respiratory disease from coal mine and silica dust.

Coal mine and silica dust cause significant respiratory disease in spite of modern dust control regulations. Susceptible individuals in exposed populations may develop fibrosing lung disease, obstructive airways disease, including chronic bronchitis and emphysema, or lung cancer. A careful occupational history that elicits exposure to respiratory hazards is the cornerstone of an accurate diagnosis. Treatment involves removal from exposure, supportive care, pulmonary rehabilitation, and when disabling disease is present, assistance obtaining compensation.

Coal Mining↗

PubMed2002

An 8-y-old boy with acute stroke and radiological signs of cerebral vasculitis after recent Mycoplasma pneumoniae infection.

A young boy was admitted to hospital for acute stroke. Cerebral angiography showed a pattern suggestive of vasculitis and a recent Mycoplasma pneumoniae infection was detected. The absence of microorganisms in cerebrospinal fluid, the pattern of vasculitis and previous reports supporting a post-infectious immunological mechanism for certain complications of M. pneumoniae infection suggest this mechanism as the cause of the stroke.

Cerebral Angiography↗

PubMed2002

Clinical efficacy of cefpodoxime in respiratory tract infection.

Acute otitis media (AOM), sinusitis and tonsillopharyngitis are respiratory tract infections frequently encountered by primary-care physicians. Increasing bacterial resistance, particularly in Streptococcus pneumoniae, which is one of the most important respiratory tract bacteria implicated in community-acquired respiratory tract infections, has led to concern about the current options for empirical antibiotic treatment and has prompted a search for effective alternative treatments. Data from in vitro studies show that cefpodoxime has good activity against the main respiratory tract pathogens, S. pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pyogenes. Clinical studies confirm the efficacy of cefpodoxime in AOM, sinusitis and tonsillopharyngitis. As with all broad-spectrum antibiotics, there is the risk of promotion of bacterial resistance associated with overuse. However, if used with care, cefpodoxime can be considered as an alternative for empirical treatment of bacterial respiratory tract infections encountered in general practice, particularly where penicillins and macrolides have reduced efficacy against the main bacterial pathogens.

Adult↗

PubMed2002

Performance assessment of community-based physicians: evaluating the reliability and validity of a tool for determining CME needs.

PURPOSE: To evaluate the reliability, validity, and feasibility of the Physician Assessment in Medical Practice (PAMP) as a means of determining the CME needs of practicing, community-based physicians. METHOD: A group of 45 randomly selected community-based physicians (19 certified family physicians and 26 general practitioners) affiliated with the Department of Family Medicine at Bruce Rappaport Faculty of Medicine, Technion Institute of Technology, Haifa, Israel, volunteered to participate in the study, conducted in 1997. All participants took a ten-station, performance-based examination designed to closely represent the physicians' work settings. At each station, a different medical problem was presented by a standardized patient. Physician-candidates' performances were assessed by physician-examiners using global ratings. The following performance domains were assessed: information gathering, diagnosis and management plan, and communication skills. A CME needs assessment score was determined for each of the participants and a CME level to meet the needs of the physician was recommended. RESULTS: Overall reliability of the examination was high (.87), with domain reliabilities ranging from.76 to.87. Reliability of the examiners' judgments of the physicians' competence was.66. All the stations' validity scores were significant, and differences in performances between family physicians and general practitioners demonstrated construct validity of the test results. Overall, the cost of running the examination was U.S. $250 per physician-candidate. CONCLUSIONS: Using the PAMP to determine CME needs of community-based physicians was found to reliable, valid, and feasible, and the cost per physician-candidate was not excessive. Performance results provided indepth information for use by both the individual physician and providers of CME programs.

Adolescent↗

PubMed2002

Comparison of two dosages of azithromycin for three days versus penicillin V for ten days in acute group A streptococcal tonsillopharyngitis.

BACKGROUND: Three-day, 10 mg/kg/day azithromycin (AZM) studies in pediatric acute group A streptococcal tonsillopharyngitis have shown contradictory bacteriologic results. This study investigates the efficacy and tolerability of two dosages of 3-day azithromycin (20 mg/kg/day and 10 mg/kg/day) compared with 10-day penicillin V. METHODS: This was a prospective, comparative, randomized, multicenter trial. Children were scheduled to return for visits at 14 days (main end point) and 1 month after the onset of treatment for clinical and bacteriologic assessment. Molecular tools were used to compare pre- and posttreatment group A beta-hemolytic Streptococcus (GABHS) isolates. RESULTS: Between November, 1997, and July, 1998, 501 patients (169 AZM 10 mg, 165 AZM 20 mg, 167 penicillin V) between 2 and 12 years old were enrolled; 500 were assessable for safety, 469 for intent to treat analysis and 420 for efficacy in the per protocol analysis. Before treatment 25 (7.9%) of 315 GABHS stains isolated from patients receiving AZM were resistant to this compound. On Day 14 pretreatment GABHS were eradicated from 78 (57.8%) of the 135 children receiving the AZM 10 mg regimen, 131 (94.2%) of the 139 receiving AZM 20 mg and 123 (84.2%) of the 146 taking penicillin. One month after the outset of treatment, bacteriologic relapses were observed in 40.5% (n = 30) of the children receiving AZM 10 mg, 14.8% (n = 18) of children taking AZM 20 mg and 13.2% (n = 15) of those treated with penicillin V. AZM 20 mg/kg/day was statistically superior to AZM 10 mg/kg/day microbiologically on Day 14 (P = 0.0001) and Day 30 (P = 0.0001) and clinically on Day 14 (P = 0.0035). AZM 20 mg/kg/day was statistically equivalent both microbiologically and clinically to standard therapy with penicillin V at all endpoints. The incidence of treatment-related adverse events was similar in the two azithromycin groups [AZM 10 mg, 31 of 169 (18.3%); AZM 20 mg, 37 of 164 (23%)] but significantly higher than those observed in the penicillin V group [5 of 166 (3%); P < 0.0001]. Most treatment-related adverse events were gastrointestinal and of mild-to-moderate severity. Fourteen patients withdrew from the trial because of adverse events (1 in the penicillin V group, 7 in the AZM 10 mg group and 6 in the AZM 20 mg group). CONCLUSION: This is the first study to demonstrate a daily dose-dependent difference in microbiologic efficacy of a regimen; 3-day AZM 20 mg/kg/day is a more effective regimen than 3-day AZM 10 mg/kg/day for pediatric GABHS tonsillopharyngitis.

Administration, Oral↗

PubMed2002

Multinational study of pneumococcal serotypes causing acute otitis media in children.

BACKGROUND: Streptococcus pneumoniae is a major cause of acute otitis media (AOM) in young children. More than 90 immunologically distinct pneumococcal serotypes have been identified, but limited information is available regarding their relative importance in AOM. METHODS: We analyzed nine existing datasets comprising pneumococcal isolates from middle ear fluid samples collected from 1994 through 2000 from 3,232 children with AOM from Finland, France, Greece, Israel, several East European countries, the US and Argentina. We examined the distribution of pneumococcal serotypes in relation to several demographic and epidemiologic variables, including gender, age, antibiotic resistance and source of culture material. RESULTS: The major serotypes identified included 19F and 23F, each comprising 13 to 25% of pneumococcal middle ear fluid isolates in most datasets; 14 and 6B, comprising 6 to 18%; whereas 6A, 19A and 9V each comprised 5 to 10%. Despite differences in location, study design and antibiotic susceptibility, each major serotype was prominent in most age groups of each dataset. Serotypes represented in the 7-valent pneumococcal conjugate vaccine (PCV-7, 4, 6B, 9V, 14, 18C, 19F, 23F) accounted for 60 to 70% of all pneumococcal isolates in the 6- to 59-month age range, but only 40 to 50% of isolates in children <6 or >/=60 months old. Serotype 3 and, in certain datasets, serotypes 1 and 5, were more important in the <6- and >/=60-month age groups. In each age group vaccine-related serotypes (mainly 6A and 19A) comprised an additional 10 to 15% of all pneumococcal isolates. Four serotypes (23F, 19F, 14 and 6B) accounted for 83% of all penicillin-resistant observations. CONCLUSIONS: This analysis of several geographically diverse datasets indicates that a limited number of serotypes, largely represented in PCV-7, accounted for the majority of episodes of pneumococcal AOM in children between 6 and 59 months of age. Certain serotypes appeared to be relatively more significant in children <6 months or >59 months of age.

Age Factors↗

PubMed2002

Emergence of group A streptococcus strains with different mechanisms of macrolide resistance.

The mechanisms of resistance to macrolides in seven group A streptococcal (Streptococcus pyogenes) isolates that were the cause of pharyngitis in children who were unsuccessfully treated with azithromycin (10 mg/kg of body weight/day for 3 days) were evaluated. All posttreatment strains were found to be genetically related to the pretreatment isolates by random amplified polymorphism DNA analysis and pulsed-field gel electrophoresis. Two isolates had acquired either a mef(A) or an erm(B) gene, responsible for macrolide efflux and ribosomal modification, respectively. Three isolates displayed mutations in the gene encoding the L4 ribosomal protein that is part of the exit tunnel within the 50S subunit of the bacterial ribosome. In the two remaining posttreatment strains, the mechanisms of macrolide resistance could not be elucidated.

Anti-Bacterial Agents↗

PubMed2002

A porous tantalum trabecular metal: basic science.

Conventional materials used for orthopedic reconstruction implants limit the design of new and improved implants. Solid metal is rigid. Porous fixation surfaces have low volumetric porosity available for biologic ingrowth and low frictional characteristics for initial implant stability and have to be bonded to solid-metal substrates. New porous structural biomaterials have been developed to help advance the current generation of prostheses and address unresolved clinical applications. Tantalum trabecular metal offers several advantages over other current conventional materials used for implants by its uniformity and structural continuity, strength, low stiffness, high porosity, and high coefficient of friction.

Biocompatible Materials↗

PubMed2001

Assessing professional behaviour and medical error.

The mission of medical schools underwent significant change in the post-Second World War period, which resulted in a de-evaluation of teaching, which in turn impacted on the type of assessment methods that emerged in the latter part of the twentieth century. Assessment based on direct observation did not receive the same degree of attention as methods such as multiple choice question and the objective structured clinical examination. During the past two decades medical educators have begun to emphasize the importance of teaching and assessing professional behaviour. It is suggested in this paper that assessment of professional behaviour can best be achieved by means of direct observation. A review of the area of assessment of clinical competence over the past 50 years reveals that it has been dominated by assessment methods that for the most part have been removed from the clinical setting in which medical students work and learn. In this paper it is proposed that there is a need to focus attention on methods of assessment which are based on the direct observation of performance that can be used in the clinical setting. Specifically, more attention needs to be directed at two areas of performance: (1) professionalism, and (2) medical error, both of which have given rise to increasing concern in the medical profession, healthcare agencies and the public at large.

Journal Article↗

PubMed1991

Disorientation and Bilateral Moderately Suprathreshold Titrated ECT.

Thirty-seven inpatients with major depression were assessed for postictal and interictal disorientation after they received 8 of 12 ECTs. In 20 patients, four of the eight assessments were after simulated ECT only. Only real, but not simulated, ECT produced postictal disorientation. Postictal disorientation was greatest after the first treatment, less after the second, and did not change in later assessments. It was shortest for person, longer for place, and longest for time, and showed a temporal time gradient. Interictal disorientation increased with the number of treatments. Two electrical stimulus variables (seizure duration and electrical stimulus intensity) correlated with the length of postictal disorientation. The influence of seizure duration and stimulus variables were independent of each other. The influence of the electrical stimulus variables was independent of the influence of demographic variables. These, however, did affect the length of postictal disorientation.

Journal Article↗