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Biomedical subjects

J McCann

Publications and source records attributed to J McCann.

At least 91 records · Page 5Linked to original sources
PubMed1997

A comparison of the performance and impact of breast cancer screening programmes in East Anglia, U.K. and Bouches du Rhône, France.

The purpose of this study was to compare results from the first screening round of two breast cancer screening programmes of similar design implemented in different health care settings. The East Anglian programme is part of the U.K. National Health Service Breast Screening Programme, which is a centralised programme with a limited number of dedicated screening units. The Bouches du Rhône programme is one of 13 French programmes based on a decentralised model using existing radiology clinics. Compliance and cancer detection rates were lower in the Bouches du Rhône programme. Detection rates for small invasive cancers (< or = 10 mm) were similar in the two programmes, although larger cancers (> or = 20 mm) were detected in the Bouches du Rhône programme. Significantly, the shift towards more favourable distribution of prognostic characteristics associated with screen-detected breast cancers compared with those arising outside the programme is less marked in the Bouches du Rhône programme. This is probably due to the more favourable underlying disease status in the district resulting from a long history of breast awareness and spontaneous mammography.

Breast Neoplasms↗
PubMed1997

A covalent fluorescent-gold immunoprobe: simultaneous detection of a pre-mRNA splicing factor by light and electron microscopy.

Immunoprobes that combine a fluorescent label with a 1.4-nm gold cluster compound have been prepared by covalent conjugation with polyclonal antibody Fab' fragments. These new immunoconjugates allow the collection of two complementary sets of data, from fluorescence and electron microscopy, from a single labeling experiment. We find that incorporation of one or more fluorescein moieties into the coordinated ligands of the 1.4-nm Nanogold gold cluster label yields a stable, dual-function immunolabel in which fluorescence quenching is negligible. In a second synthetic strategy, Nanogold and fluorescein were separately covalently conjugated to Fab' fragments to yield a probe with very similar properties. With the use of Fab' fragments, the entire probe is smaller than a whole IgG molecule, and it exhibited excellent penetration properties. It was used to localize the pre-mRNA splicing factor SC35 in the HeLa cell nucleus by both fluorescence and electron microscopy.

Fluorescein↗
PubMed1997

Testing electromagnetic fields for potential carcinogenic activity: a critical review of animal models.

In order to assess the potential of electromagnetic fields (EMF) to influence the process of carcinogenesis, it will be necessary to supplement epidemiological studies with controlled laboratory studies in animals. There are now a number of suitable assays available that focus on different histopathological forms of cancer and on different stages of carcinogenesis--induction, promotion, progression. In this review we discuss eight major systems in the context of this generalized carcinogenesis paradigm. Our aim is to bring together what is currently known about the biology of carcinogenesis in these systems in order to provide a context for evaluating EMF results as they become available. We also critically discuss EMF test results that have so far been obtained in the animal models reviewed. Most of the 19 completed studies identified were negative. However, suggestive positive results were reported in three promotion assays (in rat mammary gland, in rat liver, and in mouse skin), and in one multigeneration study in mice. Results in the rat liver assay and in the multigeneration study have only been reported in abstract form and cannot be adequately evaluated. Positive results reported in both the rat mammary gland and the mouse skin systems are of weak statistical significance and have not been independently replicated. However, it may be of interest that effects in both systems appear primarily to involve the progression stage of carcinogenesis. We suggest that more definitive conclusions as to the carcinogenic potential of EMF may require expanded test protocols that reinforce traditional carcinogenesis end points with biochemical or other parameters reflective of biological processes known to be associated with carcinogenesis in the different systems.

Animals↗
PubMed1996

An investigation of tooth size in Northern Irish people with bimaxillary dental protrusion.

This study examined tooth size in a sample of thirty Northern Irish people with bimaxillary dental protrusion. The mesiodistal diameters of all permanent teeth (excluding second and third molars) were measured. The tooth sizes were compared with a control group who did not have bimaxillary dental protrusion. The results revealed that, on average, tooth size for the overall maxillary and mandibular dentition was 5.7 per cent larger in the bimaxillary sample than in the control sample.

Adolescent↗
PubMed1996

Postmortem perianal findings in children.

The postmortem finding of anal dilation or an exposed pectinate line in children who have died under suspicious circumstances continues to raise the concern of possible sexual abuse. The following multicenter, collaborative study was designed to help address that question. Sixty-five subjects, ranging in age from birth to 17 years, were autopsied at three different sites. A standard protocol along with 35-mm cameras were used to record the results. Thirty-eight (58%) subjects were boys, and 27 (42%) were girls. Forty-two (65%) were white, 10 (15%) African-American, five (8%) Asian, three (5%) white Hispanic and five (8%) other. Fifty-seven (88%) were in Tanner stage I of secondary sexual development. Thirty-four (52%) died of natural causes, 26 (40%) from accidental injuries, three (5%) from other causes, and four (6%) as a result of a homicide. Forty-eight subjects (74%) had some dilation of the anal sphincters. In 21 children (32%), the entire anal canal, including the rectal ampulla, could be visualized. In another 21 (32%) subjects, the pectinate line was exposed. Only the outer portion of the anal canal opened in six children (10%), whereas 17 (26%) had no dilatation of the anus. Anal laxity led to flattened skin folds in 50 (77%), a shallow anal canal in 40 (62%), the exposure of both the pectinate line in 38 (59%), and the anal mucosa in 24 (37%). Venous congestion was present in 14 (22%), venous pooling in three (5%), erythema in six (9%), and increased pigmentation in eight (12%). Funneling was found in two (3%). Blood was present in three (5%), and an abrasion was discovered in one (2%). No fissures, lacerations, hemorrhoids, or scars were found in any of the children. Anal orifice size varied with the age of the child, the amount of traction applied to the buttocks, and a history of a CNS injury at the time of death. It is suggested, finally, that anal dilatation alone cannot be used a marker for prior sexual abuse and the exposure of the pectinate line should not be confused with tears or fissures of the anal verge. Further studies of children known to have been sodomized prior to death are required.

Anal Canal↗
PubMed1996

Hospital nurses' views about physical restraint use with older patients.

1. A survey of knowledge, practice and attitudes about physical restraints was completed by nursing staff (RN, LPN, CNA) from four hospitals. 2. Nurses from both geriatric and geropsychiatric units reported significantly more educational activities about restraint use than did nurses on medical units. 3. RNs had the highest knowledge scores (56%), but lacked specific information about the dangers associated with restraint use. 4. While education about restraints is important, staff need role models who can help them problem solve and examine alternatives to restraints.

Aged↗
PubMed1995

Emotional, behavioral, and physical symptoms reported by parents of sexually abused, nonabused, and allegedly abused prepubescent females.

There have been few studies that have examined emotional, behavioral, and physical symptoms that discriminate between well-defined groups of sexually abused and nonabused children. This study examined the results of a structured parent interview (SASA) completed on three matched samples of prepubescent females: 68 who were selected for nonabuse (NA Group), 68 from a sexual abuse clinic in which a perpetrator confessed (SA Group) and 68 seen at the same clinic who did not have a perpetrator confession (AA Group). Parents of girls in both the SA and AA groups reported increased sleep problems, fearfulness, emotional and behavioral changes, concentration problems, and sexual curiosity and knowledge. When contrasting the known (SA) with the allegedly abused sample (AA), self-consciousness, nightmares, and fearfulness of being left alone emerged significantly more frequently in the SA sample.

Affective Symptoms↗
PubMed1995

Gastrointestinal complications following cardiac surgery.

This study sought to determine which factors influence the mortality rate in patients developing gastrointestinal complications following cardiac surgery. Between July 1988 and January 1992, 2054 patients underwent cardiac surgical procedures at the Boston University Medical Center. Of these, 29 (1.4%) developed postoperative gastrointestinal complications. The overall mortality rate among these patients was 27% (8/29). Those who died following such complications had a higher incidence of New York Heart Association (NYHA) class IV and unstable symptoms (8/8, 100% versus 3/21, 14%; P < 0.0001), and an increased need for preoperative intra-aortic balloon pump support (4/8, 50% versus 1/21, 5%; P < 0.004). The need for gastrointestinal surgical intervention increased the mortality rate significantly compared with patients managed medically (8/18, 44% versus 0/11, 0%; P < 0.01). Patients with ischemic bowel also had a significantly higher mortality (5/5, 100% versus 3/24, 12%; P < 0.001). It is concluded that most patients with gastrointestinal complications following cardiac surgery can be treated, and with acceptable mortality rates. The presence of unstable symptoms, preoperative intra-aortic balloon pump support, ischemic bowel and the need for gastrointestinal surgical intervention adversely affect mortality.

Aged↗
PubMed1995

Monitoring interval cancers in breast screening programmes: the east Anglian experience. Quality Assurance Management Group of the East Anglian Breast Screening Programme.

Interval cancer rates are a major determinant of the success of a screening programme. In the Swedish two county study, on which the United Kingdom programme is based, a 39% reduction in mortality was observed in screened women aged 50-64. Using data from the Swedish study, the relationship between interval cancer incidence and the likely future effect on breast cancer mortality was quantified. In East Anglia, as elsewhere in the United Kingdom, interval cancers rates are nearly double those obtained in Sweden: interval cancer rates in the first, second, and third years respectively, after a negative screen were 24%, 59%, and 79% of the expected underlying incidence in the absence of screening. The corresponding figures from the two county study were 17%, 30%, and 56%. From these it was estimated that the mortality reduction in East Anglia will be 21%, which is lower than the 35% observed in invited women in this age group in the Swedish two county study and the 25% specified in the Health of the Nation target. In a rereading exercise, using screening mammograms from women who were screen normal, who had screen detected cancers, or who subsequently developed interval cancers, four out of five radiologists recommended recall for around 70% of the original mammograms (classed as screen normal at time of screening) from 33 interval cancers. This suggests that sensitivity is a contributory factor to the higher interval cancer rates in East Anglia.

Aged↗