Search PubMed⌕ Search

Biomedical subjects

D Robinson

Publications and source records attributed to D Robinson.

At least 343 records · Page 19Linked to original sources

The parental origin of the missing or additional chromosome in 45,X and 47,XXX females.

We used X-linked DNA polymorphisms to study the parental origin of the missing or additional X chromosome in conceptuses with 45,X or 47,XXX chromosome constitutions. Fifty-three (80.3%) of 66 cases of sex chromosome monosomy had a maternal X, demonstrating that paternal sex chromosome loss is the most common error leading to this condition. In contrast, 29 (93.5%) of 31 47,XXX cases resulted from maternal nondisjunction. In studies of parental age, we detected no obvious parental age effect for sex chromosome monosomy. For the 47,XXXs, there was an apparent association between increasing maternal age and errors at maternal meiosis I, but not maternal meiosis II. In other analyses, we detected no obvious effect of parental origin on the phenotype of either 45,X or 47,XXX conceptuses, at least as measured by comparing the ratio of paternal:maternal errors among different ascertainment categories.

Aneuploidy↗

Pelvic allograft. A case report with a follow-up evaluation of 5.5 years.

A 23-year-old man with a large chondrosarcoma of the right bony pelvis was successfully treated by limb-saving internal hemipelvectomy and anatomic reconstruction of the pelvis by a pelvic osteoarticular allograft including the acetabulum. Optimum anatomic fit was achieved at the hip joint as well as at the iliac and pubic host-graft junctions, which were fixed with plates and screws. This reconstruction restored stability, leg length, hip motion, and cosmesis. Five and one-half years postoperatively, the patient remained asymptomatic with good functional and roentgenographic results.

Adult↗

The Family Relationship Index: validity data.

The Family Relationship Index (FRI) is a self-report measure that provides an overall index of the quality of the family environment, as well as subscores that reflect family cohesion, expressiveness, and conflict. The current study is based on 53 families who had approached a family service agency for counseling and who had completed an FRI measure prior to intake. The construct validity of the FRI scores was evaluated by comparing them to measures of family functioning provided by experienced family therapists as part of the intake process. Support for the construct validity of the composite index and two of the subscores, Family Cohesion and Family Conflict, was obtained.

Adult↗

Inheritance and phenotypic expression of a t(7;9)(q36;q34)mat.

We describe a subtle familial chromosome rearrangement which involves 7q36 and 9q34. The clinical manifestations of 3 apparently balanced individuals with presumed identical translocation breakpoints are presented. In addition, the phenotypes of 2 cytogenetically unbalanced sibs in the same nuclear family are compared.

Adolescent↗

Three-color fluorescence in situ hybridization for the simultaneous detection of multiple nucleic acid sequences.

A method is described for visualizing three nucleic acid sequences simultaneously by in situ hybridization using a new blue immunofluorescent label, amino methyl coumarin acetic acid (AMCA), in combination with green and red fluorescing FITC and TRITC. Three chromosome-specific repetitive probes labeled with either amino acetyl fluorene (AAF), mercury, or biotin were hybridized simultaneously to metaphase chromosomes prepared from human blood lymphocytes or to interphase tumor nuclei. Conditions for the combined use of three immunocytochemical affinity systems as well as the optimal spectral separation of the three fluorescing labels have been determined. Three-color in situ hybridization was applied to the study of numerical chromosome abnormalities as occur in human solid tumors. Further applications of this method in prenatal diagnosis for the detection of aneuploidy of the most frequently involved autosomes, as well as for the quantification of gene copy number and mRNA expression, are discussed.

Base Sequence↗

Spondyloepiphyseal dysplasia associated with progressive arthropathy. An unusual disorder mimicking juvenile rheumatoid arthritis.

A family is presented with three affected siblings suffering from a rare form of spondyloepiphyseal dysplasia with progressive arthropathy affecting most joints of the body except for the craniofacial skeleton. This syndrome, probably of autosomal recessive inheritance, clinically presents diffuse and chronic joint involvement and should be differentiated from juvenile rheumatoid arthritis and other rheumatic disorders.

Adolescent↗

End-user reactions towards working with Computer-Based Information Retrieval Systems (CBIRS).

This paper reports the results of an investigation of users' perceptions of and feelings towards working with Computer-Based Information Retrieval Systems (CBIRS). Detailed questionnaires were distributed to members of the United Kingdom Online User Group (UKOLUG), to database users within a large organisation (Site A), and to end-users of a complex commercial database containing information about electronic components (Codus). The three groups differed significantly in their perceptions towards working with a CBIRS, with UKOLUG members holding the most positive perceptions. More frequent use of the CBIRS was found to be significantly related to perceived functional utility of the CBIRS in all three groups. In only two of the groups (UKOLUG and Codus) was perceived difficulty in operating the system negatively related to frequency of use. Job attitudes were not significantly related with perceptions towards working with a CBIRS, but were significantly related with current usage of the CBIRS. For all three groups, reported 'planfulness' (tendency to plan) when using a CBIRS was positively related to feelings of pressure when using the system. The paper discusses the implications of the study's findings for future research and development in the field of human-computer interaction.

Journal Article↗

Fate of allogeneic embryonal chick chondrocytes implanted orthotopically, as determined by the host's age.

Chondrocytes derived from chick embryos can be successfully implanted in defects of adult chick articular cartilage surfaces. Such implants thrive in their implantation site and create a new articular surface. The chondrocytes mature and hypertrophy in the orthotopic site without invoking an immune response. Eventually a steady state is reached in which mature chondrocytes resurface the defect while in the deeper areas spongy bone replaces the hypertrophic chondrocytes. Time schedules of these repair events have been studied in hosts of different ages. We compared 4-month-old chicks with 3-year-old chickens. The embryonal chondrocytes implanted in the latter group underwent an accelerated aging process. The defects were completely filled-up after 1 month as compared with 2-3 months in the younger age group. Endochondral ossification in the older group was evident as early as 2 months post implantation and was completed after 6 months. This contrasts with the situation in the younger group where the chondrocytes only began to hypertrophy after 6 months. At this stage endochondral ossification was hardly seen at all. A unique response to the cartilaginous implants is seen in the old group only in the vicinity of the reparative tissue, accumulation of hematopoietic centers. This study seem to indicate that the host's environment affects the "biological clock", i.e. rate and degree of aging of the implanted cells, as well as their matrices.

Age Factors↗

Morphometric analysis of chronic B-cell leukemias--an aid to the classification of lymphoid cell types.

In order to evaluate the ultrastructural features which may be of relevance in distinguishing cells from the various chronic B-cell leukemias, a morphometric analysis was performed on a large number of cells from each disease group. The parameters selected were: cell size, nucleo: cytoplasmic ratio, chromatin condensation, size of the nucleolus and degree of irregularity of both the nucleus and the cytoplasmic outlines. The mean values obtained for each parameter for each disease group were compared statistically. In disorders in which the cells have villous cytoplasmic projections, the quantitative analysis of the cellular features was helpful to characterise the different types of B cells involved. Thus, cells from cases of splenic lymphoma were found to be different from those of hairy cell leukemia, and a variant form of HCL was also identified by its distinct ultrastructural features. Similarly cells from chronic lymphocytic, prolymphocytic leukemia and an intermediate group CLL/PL were identified by the size of the nucleolus and the degree of chromatin condensation. The morphometric findings provided an objective morphological basis for the differential diagnosis between these closely related B-cell leukemias which was further supported by differences in the cells immunophenotype.

Cell Nucleolus↗

Clinical experience with zidovudine for patients with acquired immune deficiency syndrome and acquired immune deficiency syndrome-related complex.

We have treated 113 patients with zidovudine since its licensure, 80 with acquired immunodeficiency syndrome and 33 with acquired immunodeficiency syndrome-related complex. This paper reports on the efficacy and toxicity observed in these patients. Improved well-being, reduced frequency and severity of opportunist infections were notable in the first year of follow-up. More rapid improvement in pulmonary physiological tests during recovery from Pneumocystis carinii pneumonia was also observed in treated patients. Patients with lower initial platelet counts showed early increases in platelet counts. There was a consistent fall in human immunodeficiency virus (HIV) p24 antigen during treatment, although not always to undetectable levels. CD4 cell counts showed a rise in the first months of treatment but these were not sustained, despite continuing clinical benefit. Neuropsychological and clinical evidence of benefit in HIV encephalopathy are described. We have analysed the factors influencing marrow toxicity and have found that low CD4 count and the intercurrent use of ganciclovir and dapsone increase myelotoxicity. We describe the clinical and biochemical features of the myopathy associated with long-term use of zidovudine and summarise our findings on dose-reduction associated meningo-encephalitis.

AIDS-Related Complex↗

Sonographic diagnosis of intrauterine growth retardation using the postnatal ponderal index and the crown-heel length as standards of diagnosis.

One hundred twenty-one patients underwent an ultrasound examination within 48 hours of delivery to assess prospectively the reliability of the diagnosis of intrauterine growth retardation. Sonographic parameters examined included the abdominal circumference, sonographic estimate of fetal weight, the head to abdominal circumference ratio, and the femur length to abdominal circumference ratio. The best obstetric estimate of gestational age was used. The diagnosis of growth retardation was based on the postnatal ponderal index, and or the birthweight and crown-heel length percentiles. Seventeen infants were growth retarded. Fifteen infants had a birthweight less than the 10th percentile, but only nine (60%) were either asymmetrically growth retarded (by their ponderal index) or symmetrically growth retarded (by virtue of a birthweight and length less than the 10th percentile). All sonographic parameters were better able to predict a birthweight below the 10th percentile for gestational age than growth retardation. An abdominal circumference less than the 2.5 percentile for gestational age had the highest sensitivity for growth retardation (88.0%) of the parameters studied. Only the abdominal circumference centile identified all infants with either symmetric growth retardation or asymmetric growth retardation associated with a birthweight below the 10th percentile. A sonographic estimate of fetal weight below the 10th percentile had the highest positive predictive value for growth retardation--38%. In contrast to the overall poor positive predictive values, the negative predictive values for all parameters studied exceeded 90%. Combining the abdominal circumference percentile with one of the three remaining techniques did not significantly improve diagnostic accuracy.(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗

Isolation of Murray Valley encephalitis and Ross River viruses from Aedes normanensis (Diptera: Culicidae) in Western Australia.

Of eight viruses isolated from 28,909 female (643 pools) Aedes normanensis collected from the north of Western Australia, two were identified as Murray Valley encephalitis virus and six as Ross River virus. The two isolates of Murray Valley encephalitis virus represent the first confirmed isolations of this virus from an Aedes species. The possible implications of these findings with regard to virus survival mechanisms during the dry season are discussed.

Aedes↗

Technetium-99m labeled monoclonal antibodies in the detection of metastatic melanoma.

Twenty-six stage II/III malignant melanoma patients with 321 measurable metastatic lesions were imaged using Fab fragments of an IgG murine monoclonal antibody labeled specifically with 10-30 mCi Tc-99m with a bi-functional chelating method (NeoRx, Seattle, WA). There were no side effects or adverse reactions. Immunoscintigraphy demonstrated 66.6% of lesions larger than 1 cm and 92.5% of lesions larger than 3 cm. Most frequently detected metastases were in lymph nodes, subcutaneous areas, and bone. Of lesions less than 1 cm, 23.6% were detected if superficial cutaneous lesions were excluded. The smallest detectable lesion was 4 mm. Twenty-one additional clinically unsuspected sites were visualized in 12 of the 26 patients studied. Of these, 56% were confirmed as metastasis by other tests. There were apparent nonspecific localizations owing to other causes, including fracture, varicosities, skin abscess and pneumonitis. Increased experience in image analysis facilitates correct interpretation of these localizations. This study demonstrates that imaging with Tc-99m labeled antibody fragments detects melanoma lesions in organs routinely surveyed and in other areas not routinely assessed by other imaging techniques. The procedure is readily performed and safe. The principal advantage of the test is its ability to survey the entire body and all organs with a single test. Its principal limitation, in common with other diagnostic imaging procedures, is its poor sensitivity for detecting lesions less than 1 cm.

Adult↗

An overlapping pubic dislocation treated by closed reduction: case report and review of the literature.

An overlapping dislocation of the symphysis pubis is a rare injury caused by either side-to-side compression or hyperextension. We hereby describe a case of such injury sustained during parachuting and reduced by closed means. This case appears to be the first described in the literature where no damage to the urogenital tract was observed. The patient is asymptomatic 1 year later.

Adult↗