PubMed Health⌕ Search

Biomedical subjects

D Lord

Publications and source records attributed to D Lord.

16 recordsLinked to original sources

Crash and injury reduction following installation of roundabouts in the United States.

OBJECTIVES: This study estimated potential reductions in motor vehicle crashes and injuries associated with the use of roundabouts as an alternative to signal and stop sign control at intersections in the United States. METHODS: An empiric Bayes procedure was used to estimate changes in motor vehicle crashes following conversion of 24 intersections from stop sign and traffic signal control to modern roundabouts. RESULTS: There were highly significant reductions of 38% for all crash severities combined and of 76% for all injury crashes. Reductions in the numbers of fatal and incapacitating injury crashes were estimated at about 90%. CONCLUSIONS: Results are consistent with numerous international studies and suggest that roundabout installation should be strongly promoted as an effective safety treatment.

Accidents, Traffic↗

Effects of continuous therapeutic ultrasound on growth and metastasis of subcutaneous murine tumors.

BACKGROUND AND PURPOSE: The use of therapeutic ultrasound (US) in the presence of malignant neoplasms has been contraindicated in physical therapy practice despite a lack of convincing scientific evidence. Some studies have shown that high levels of US, which increase tissue temperatures greater than 42 degrees C, can kill tumors. We sought to determine whether the application of continuous therapeutic US would alter the growth or metastasis of methylcholanthrene-induced solid tumors in mice. SUBJECTS: Seventy-one female C57BL/6 mice, age 6 to 8 weeks, received subcutaneous injections of 5 x 10(5) tumor cells. METHODS: When tumors grew to 0.5 cm in diameter, the mice were randomly assigned to either a control group (n = 34) or an experimental group (n = 37). The experimental group received 10 treatments over a 2-week period of 3-MHz continuous US at 1.0 W/cm2 for 5 minutes, using a 0.5-cm2 sound head directly over the tumor. The control group received the same handling except for the US treatment. Tumor dimensions were measured on days 1 (baseline), 7 (midtreatment), and 14 (preexcision and postexcision). Tumors were weighed after excision, and the mice were evaluated by necropsy and histopathology of regional lymph nodes. RESULTS: All tumors grew larger over time, but final tumor volume and weight were larger in the experimental group (789 mm3 and 0.932 g) than in the control group (395 mm3 and 0.506 g). No significant difference existed in the number of metastatic lymph nodes between groups. CONCLUSION AND DISCUSSION: Continuous therapeutic US increased the volume and weight of subcutaneous murine tumors in mice. We urge caution in the use of continuous therapeutic US in the areas of tumors or suspected tumors.

Analysis of Variance↗

Evaluation of iontophoretically applied dexamethasone for painful pathologic temporomandibular joints.

The effects of iontophoretically applied dexamethasone in a lidocaine vehicle were compared with those of saline placebo in 53 patients with one of three diagnoses of painful temporomandibular joint pathologic conditions: disk displacement with reduction, disk displacement without reduction, and osteoarthritis. Both dexamethasone and the saline placebo produced a significant reduction in pain scores from baseline levels after the first two of three treatments. There were no observed differences, however, in pain report or mandibular range of motion between the dexamethasone and placebo groups. A trend for pain relief was noted in the subgroup that received dexamethasone with a diagnosis of osteoarthritis. Results may reflect varying degrees of inflammation or central nervous system hyperexcitability, or both, in this heterogeneous study sample. Potential confounding variables were lack of knowledge of actual drug penetration, the effects of electric current transmitted by the iontophoresor, and pain reduction caused by cyclic fluctuations in symptoms. These data suggest that iontophoretically applied dexamethasone is no more effective than saline placebo in providing pain relief in patients with temporomandibular joint pain.

Adult↗

Detection of hereditary haemochromatosis in an HLA-identical pedigree showing discordance between HLA class I genes and the disease locus.

Hereditary haemochromatosis is a recessive disease in which primary hepatocellular carcinoma, complicating cirrhosis, is responsible for about one-third of deaths in affected homozygotes. We describe a unique HLA haplo-identical pedigree showing parent-to-offspring transmission of hereditary haemochromatosis in whom HLA typing studies, including class I and class II allogenotype analysis, were of no benefit in identifying affected homozygotes. However, affected siblings in the pre-cirrhotic stage of haemochromatosis, with apparent discordance between the haemochromatosis allele and class I loci on chromosome 6, were detected by undertaking a family study, using analysis of serum parameters of iron status in combination with magnetic resonance imaging (MRI). This pedigree emphasises the critical importance of genetic and non-invasive methods for the identification of asymptomatic homozygotes before cirrhosis develops.

Alleles↗

The inheritance of MS susceptibility.

The object of this study was to determine, if possible, the mode of inheritance of the susceptibility to multiple sclerosis (MS). It was known that no single-gene model could fit the observations, so oligogenic models (models involving a small number of genes) were sought. Oligogenic hypotheses were tested against the available population data for MS until a reasonable level of agreement was found. The best-fitting simple hypothesis was this: MS occurs only in people who are homozygous for a recessive gene and carry a dominant X gene, and then only with reduced penetrance. The dangerous allele m- at the autosomal locus appears to be fairly uniformly distributed across England, Ireland and Canada, occurring in 10-30% of the gene pool. There are large variations in the frequency of the allele s- at the X-locus, ranging from 10% up to 72% of the gene pool. The penetrance varies significantly with geographical location, but nowhere approaches unity, so that the environmental factors are of great importance. The hypothesis explains the broad features of the population pattern of the occurrence of MS and it gives an outstanding fit to the best available data on MS in relatives. The result may assist attempts to map the genetic data on MS, opens the way for a reassessment of the attempts to identify the environmental factors, and it makes possible the completion of nonempirical risk tables for various countries. Similar techniques may be applied to other disorders with a genetic component in their aetiology.

Disease Susceptibility↗

Habitat specificity of the acanthocephalan Acanthocephalus clavula (Dujardin, 1845) in eels Anguilla anguilla (L).

The habitat specificity of the acanthocephalan Acanthocephalus clavula in the alimentary tract of eels was studied in natural infections and in fish maintained experimentally under different regimes. The parasite exhibited a preference for a particular region (55 to 65%) of the alimentary canal which did not differ in different species of host, but habitat specificity was not very precise as there was considerable variation between individual hosts and A. calvula was capable of surviving and maturing in all regions of the intestine. The mean position of males was slightly anterior to that of females, and the over-all sex ratio was in favour of females. At high levels of infection the range of the parasites was extended and the means position was significantly more anterior when compared to single worm infections. The parasite remains in the same site throughout the course of an infection: there was no posterior migration and gravid females occurred in the same proportion in all regions of the intestine. The mean position of the parasite did not change when the host was starved, or maintained in 100% sea water or with reduced aeration or at high temperature. The results were compared with the habitat specificity exhibited by other species of freshwater fish acanthocephalans, and it was concluded that A. clavula was as adaptable and hardy as its present host, the eel.

Acanthocephala↗

Comparison of eight kits for the diagnosis of pregnancy.

The results obtained with eight pregnancy kits on 735 urines were compared. Overall accuracies were similar and fairly high (93.4 to 95.37%), although only 78.28% of all pregnancies were simultaneously detected by all eight kits. It is suggested that the different performances of each kit could be accounted for not only by lack of product homologation, differences in kit sensitivity, and laboratorian error, but also by the presence of various hormonal components in various concentrations in the urines of pregnant women, and by the presence of different antibodies against these hormonal components in various concentrations in the antisera included in the various kits.

Chlorpromazine↗

Phase 2 study of mitozantrone in combination with chlorambucil and prednisolone for relapsed and refractory non-Hodgkins lymphoma.

Thirty-six patients with non-Hodgkin's lymphoma (NHL) (comprising patients with refractory or relapsed disease and eight elderly, unfit patients with de novo disease) were treated with mitozantrone, chlorambucil and prednisolone on an out-patient basis. Fifteen patients had low grade (LG) disease, five patients intermediate grade (IG) disease and 16 patients high grade (HG) disease and 31/36 had stage IV disease. All elderly patients had IG or HG disease. The regimen was well-tolerated. After six courses of chemotherapy, there was a 69 per cent response rate with 33 per cent in complete remission. The median duration of remission was 15 months. The overall 3-year projected survival was 38 per cent; 27 per cent for LG disease and 47 per cent for HG and IG disease. Responses did not appear durable for either HG or LG disease unless CR was achieved early on. Three of the eight patients treated de novo (mean age 71 years) have survived disease-free, between 28 and 38 months from entry. This study indicates that mitozantrone-based regimens have promising activity in NHL and require further evaluation. The low toxicity combined with worthwhile remissions make this an attractive first-line option for elderly patients.

Adult↗