Search PubMed⌕ Search

Biomedical subjects

N E MacDonald

Publications and source records attributed to N E MacDonald.

At least 37 records · Page 2Linked to original sources

Liposomal amphotericin B for postoperative Aspergillus fumigatus endocarditis.

A 10-month-old infant girl presented with Aspergillus fumigatus endocarditis localized to a Gore-Tex patch used as part of the repair for double-outlet right ventricle. A new liposomal preparation of amphotericin B combined with surgical vegectomy resulted in a successful outcome with no evidence of disease recurrence at 15 months' follow-up. Echocardiography provided an optimal modality for ongoing evaluation of therapeutic outcome.

Amphotericin B↗

Relationship between parental occupation and children's oropharyngeal colonization with Neisseria meningitidis.

We explored, during an outbreak of meningococcal disease, whether children of parents with workplace exposure to children were at increased risk of oropharyngeal colonization with Neisseria meningitidis. In comparison with children of parents without workplace exposure to children, the risk of colonization was not increased (odds ratio = 1.62; 95% confidence interval, 0.56 to 4.72). Therefore a parent's occupation does not appear to increase the risk of their children's colonization with N. meningitidis.

Adolescent↗

Cystic fibrosis carrier screening in a high-risk population. Participation based on a traditional recruitment process.

OBJECTIVE: Recent advances in molecular genetic (DNA) technology have permitted identification of previously undetectable cystic fibrosis (CF) carriers. Although research has been initiated in the general population, to our knowledge no published studies have looked at the utilization of DNA-based carrier screening in the high-risk CF population (family history of CF). DESIGN: Cross-sectional, diagnostic open trial. SETTING: Carrier testing was offered to a high-risk CF population via adult patients with CF or parents of pediatric patients with CF attending two regional CF clinics over a 3-year period. PARTICIPANTS: Consecutive sample of virtually all patients with CF (n = 118) from a population of 1 million. MAIN RESULTS: Despite free services, written follow-up, and counseling for 99% of patients attending the CF clinic, there was less than 10% participation from high-risk family members (168 blood relatives and 26 spouses of identified carriers or patients with CF; 38 and 156 persons from the adult and pediatric clinic families, respectively). Nevertheless, we identified 91 CF carriers among the 168 high-risk relatives. This is comparable to the number of carriers detected in general population carrier screening that has tested substantially more individuals (> 3000 per study). CONCLUSIONS: Our results suggest that research concerning CF carrier screening not only focus on data about fundamental program resources and numbers of carriers detected but also investigate how information about the availability of carrier screening is disseminated, the motivation behind testing, and the perceived relevance of test results by those tested in the high-risk population. These issues are increasingly relevant as screening becomes feasible using DNA testing for far more prevalent disorders (such as breast cancer and diabetes).

Adolescent↗

Molecular typing of Haemophilus influenzae using a DNA probe and multiplex PCR.

The use of new molecular typing methods for the characterization of Haemophilus influenzae strains is reported. Sixty-four isolates of H. influenzae originating from different types of infection and obtained from eight hospitals across Canada were first analysed for restriction polymorphism. Chromosomal DNA fragments generated by two different combinations of restriction endonucleases were electrophoresed and transferred to nylon membranes before hybridization with a species specific 32P-labelled DNA fragment (5 kb) used as a probe. The combinations Bg/II/PstI led to 11 typing groups (A-K) and BamHI/Bg/II/PstI to 14 sub-groups, respectively. Most of the isolates retrieved from cerebrospinal fluids (10/13; 76.9%) were classified in two groups (A and B) and two sub-groups. Isolates from respiratory tract infections were mostly found in groups C and E (24/32; 75.0%), and divided into seven sub-groups. Selected ampicillin-resistant, beta-lactamase-negative strains were also found in groups C and E (11/14; 78.6%). Isolates from conjunctivitis and acute otitis media were classified in various groups. All biotypes (I-VIII) and serotypes (none, a-f) were spread among the typing groups although biotype I prevailed in groups A, B, and G; II in group E (sub-group 6); and III in group C. A PCR approach derived from the typing system was also tested. A set of 25-mer primers was selected from the 5-kb DNA probe for the amplification of a 317-bp region. This set of primers was used concomitantly in a PCR multiplex assay with a set of primers selected from the nucleotide sequence of the gene encoding the H. influenzae P1 protein. This multiplex assay was also able to discriminate the clonal origin of some H. influenzae strains because size polymorphism was observed in PCR products. The PCR approach was then used to determine the genetic relatedness of H. influenzae strains found persistently in sputa of some patients with cystic fibrosis. Genetically related strains could be isolated from some patients even after antibiotherapy and months between visits, whereas other patients showed distinct strains. In summary, our typing system is able to provide new characteristics for strains having identical biotype or serotype. The rapid PCR alternative may prove useful for specific epidemiological and strain-tracking studies.

Adolescent↗

Canadian street youth: correlates of sexual risk-taking activity.

The purpose of this study was to develop a national perspective on the sexual activity of street youth in Canada and to determine the correlates of risky sexual behavior according to street youth's link to the street. Five categories of street youth (sex industry workers, heavy drug and/or alcohol users, young offenders, homeless and unemployed) ages 15 to 20 years were recruited in 1988 from 10 Canadian urban centers to participate in a 45-minute structured interview focusing on knowledge and attitudes regarding sexually transmitted diseases (STD)/human immunodeficiency virus, current sexual practices, sexual and STD history, demographic background, alcohol/drug use and relationship with parents and peers. Data from the survey were also compared with findings from more than 15,000 non-street youth adolescents surveyed in the same year with the use of parallel questionnaires. Of 712 street youth surveyed (391 males, mean age 17.3 years; 321 females, mean age 16.8 years), the majority were sexually active (95% males, 93% females) and 22% reported at least one previous STD (16% males, 30% females). The lowest STD rates were in unemployed males (5%) and the highest (68%) in female sex industry workers. STD/human immunodeficiency virus high risk behaviors were frequent with 47% of males and 41% of females having had at least 10 different partners, 73% of males and 75% of females inconsistently using condoms and 22% of males and 24% of females participating in anal intercourse. Even among sex industry workers more than 40% used condoms inconsistently.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

High-risk STD/HIV behavior among college students.

The current sexually transmitted disease (STD) epidemic in adolescents has led to concern about the potential for spread of the human immunodeficiency virus (HIV). In 1988, a total of 5514 students in first-year community college and university classrooms across Canada were surveyed to assess STD/HIV-related knowledge, attitudes, and risk behavior. The students' mean age was 19.7 years; the male-to-female ratio was 1:1.4. Students knew more about HIV/acquired immunodeficiency syndrome than other STDs. Of the 74.3% of the men and 68.9% of the women who were coitally active, 14.3% of the men and 18.6% of the women had participated in anal intercourse and 5.5% reported a previous STD. Only 24.8% of the men and 15.6% of the women always used a condom during sexual intercourse. Among the 21.3% of the men and 8.6% of the women with 10 or more partners, regular condom use was reported in only 21% and 7.5%, respectively. In this subgroup, anal intercourse was practiced by 26.9% of the men and 34.8% of the women, and previous STD was reported by 10.6% and 24.2%, respectively. Factors associated with not using a condom included number of sexual partners, embarrassment about condom purchase, difficulty discussing condom use with a partner, use of oral contraceptives, insufficient knowledge of HIV/STDs, and the belief that condoms interfere with sexual pleasure. These factors are potentially amenable to change. Effective, behaviorally focused educational programs are needed to improve condom use and reduce STD/HIV risk.

Adolescent↗

Parental attitudes toward pediatric organ donation: a survey.

We conducted a telephone survey of parents in the National Capital Region to assess their intention to donate their child's organs and to provide physicians with information that could help alleviate their concerns about approaching parents for consent. Of 339 parents who agreed to answer questions after being given details of their child's "death" 288 (85%) said that they would be willing to donate their child's organs. The degree of willingness was associated with the certainty of death, altruism and empathy toward children in need of an organ, previous discussion of organ donation with a family member and knowledge of an adolescent or adult child's attitude toward donation. Factors that inhibited the intention to donate included uncertainty of death, insufficient information from medical professionals and fear of multilation. The child's age was not significantly associated with intention to donate. Concordance between the results and actual donation rates in Canada and the United States supports the generalizability of the survey findings.

Adolescent↗

Chronic disease and its impact. The adolescent's perspective.

Although evidence suggests that adolescents with chronic illness are at a greater risk for psychosocial disability, little is known about the adolescent's perception of the impact of the disease on his or her day-to-day life. Standardized measures of coping strategies, mastery, self-efficacy, social support, depression, and a semistructured interview on everyday difficulties were administered to matched groups (sex and age) of 31 adolescents with cystic fibrosis, 31 adolescents with diabetes, and 31 healthy controls. No differences were found between control and adolescents with a chronic disease responses on the standardized measures. The semistructured interview, however, revealed that the adolescent's perception of his or her physical health and the reaction of other family members to the illness were important sources of stress. These findings suggest that, in general, adolescents with a chronic illness cope effectively with their disability but that parents and clinicians must be sensitive to the adolescents' feelings and concerns regarding their health and its impact on the family.

Adolescent↗

Influenza in children with cancer.

We prospectively followed a group of unimmunized, immunosuppressed children with cancer to determine their relative risk of influenza and the severity of infection compared with those of siblings or matched community controls. The incidence of influenza infection was higher in children with cancer (23/73, 32%) than in control subjects (10/70, 14%, p = 0.02). A preseason hemagglutination inhibition titer greater than or equal to 1:32, generally used as a marker of successful immunization in vaccine trials, was protective for all children in the control groups, but did not prevent influenza infection in 24% of the patients with cancer. Infection rates of patients and community controls with titers greater than or equal to 1:32 differed significantly (p = 0.006). No significant differences were noted in duration of reported symptoms between groups, and clinical complications occurred too infrequently to analyze. However, 2 (11%) of 18 of the cancer patients with positive culture results were hospitalized during the illness and one patient developed a nosocomial infection. None of the control children was hospitalized. These findings suggest the need for further study of the immunologic response of immunosuppressed children to influenza infection and a clinical efficacy trial of the influenza vaccine in these patients.

Adolescent↗

Parental care and overprotection of children with cystic fibrosis.

Parental overprotection has often been clinically associated with the psychological maladjustment of children with a chronic disease. The purpose of this study was to examine parental care and overprotection in children with cystic fibrosis compared to healthy controls. Results indicated no differences in the level of parental care or overprotection between controls and children with cystic fibrosis. However, a number of significant correlations were found between parental care and overprotection and children's psychosocial functioning. In particular, positive correlations were found between parental overprotection and poor psychosocial functioning in children with cystic fibrosis, whereas, poor psychosocial functioning in healthy children was associated with lack of parental care. Parental overprotection and care appear to play important roles in the emotional and psychological functioning of healthy and chronically ill children.

Adaptation, Psychological↗

Assessment of readiness to transfer to adult care for adolescents with cystic fibrosis.

With the increasing availability of adult cystic fibrosis clinics, pediatric caregivers are faced with deciding whether an adolescent is ready for transfer. Twenty-two pediatric caregivers, ten adult caregivers, and three adult patients were interviewed to determine what behaviors and knowledge they perceived as essential for successful transition to adult care. No differences were noted between the pediatric and adult caregivers' responses. Based on their responses, a 24-item questionnaire was developed to assess readiness for transfer of 36 adolescents with cystic fibrosis. The questionnaire scores were found to be better predictors than age for success in transfer to adult care. The questionnaire allows the pediatric staff to focus on those areas that adolescents may need further preparation.

Adolescent↗