PubMed Health⌕ Search

Biomedical subjects

Peter J Shaw

Publications and source records attributed to Peter J Shaw.

24 records · Page 2Linked to original sources
PubMed2002

Early and late invasive pneumococcal infection following stem cell transplantation: a European Bone Marrow Transplantation survey.

Streptococcus pneumoniae (S. pneumoniae) may cause severe and lethal infections months and years following stem cell transplantation (SCT). In a prospective survey over a 3.5-year period, we assessed the incidence, risk factors and outcome for invasive pneumococcal infection (IPI) following SCT. Fifty-one episodes of IPI were reported: 43 episodes after bone marrow transplantation (BMT) and 8 after peripheral blood stem cell transplantation (PBSCT); 35 after allogeneic SCT and 16 after autologous SCT. Seven IPI episodes, all bacteraemias, were defined as early, occurring 1-35 d (median 3 d) post transplantation. Forty-four episodes were defined as late (> or = 100 d post SCT), occurring 4 months to 10 years (median 17 months) post transplantation. The incidences of early and late IPI were 2.03/1000 and 8.63/1000 transplantations respectively (P = 0.001). A higher incidence of late IPI was observed after BMT than after PBSCT (10.99 versus 3.23/1000; P < 0.01) and after allogeneic versus autologous SCT (12.20 versus 4.60/1000; P < 0.01). There was a higher estimated incidence of IPI in allogeneic patients with than in those without graft-versus-host disease (GVHD) (18.85 versus 8.25/1000; P = 0.015). The mortality rate was 20%, including 2/7 of early and 8/44 of late IPI. S. pneumoniae is a rare but important complication during the aplastic phase after SCT. In conclusion, S. pneumoniae is a significant cause of morbidity late post-transplantation, especially in allogeneic patients, and particularly those with GVHD. The high IPI mortality rate, both early and late post-transplantation, requires preventive approaches, mainly effective immunization.

Adolescent↗
PubMed2002

Suspected infection in children with cancer.

A common complication of the intensive therapy that children with cancer receive is infection. The Oncology Unit of The Children's Hospital at Westmead maintains a comprehensive database of all admissions for suspected sepsis. From July 1994 to June 1999 broad-spectrum antibiotics were commenced in 2331 episodes. With early and aggressive use of empirical amphotericin B, 545 courses were given. Bacteraemia was documented in 701 episodes and invasive fungal disease in 73. Trends seen during the study included: (i) the proportion of febrile neutropenic patients receiving granulocyte colony stimulating factor increased from 40% to 60%; (ii) the mean neutrophil count at cessation of antibiotics fell from 0.97 to 0.63 x 10(9) cells/L for patients not receiving growth factors; (iii) the proportion of non-albicans Candida species infections increased. In addition, an outbreak of infection caused by Scedosporium sp. was documented; (iv) first-line empirical antibiotic combinations containing vancomycin fell from 20% to 7%; and (v) the ability to maintain or escalate anti-fungal therapy with reduced nephrotoxicity through use of lipid formulations of amphotericin was increasingly apparent in high-risk patients. During the study, infection was the primary cause of death in 11 non-bone marrow transplant (BMT) patients (five fungal, four viral, one bacterial infection and one sepsis syndrome) and five BMT patients (two bacterial and three viral). A prospective randomized study of toxicity due to amphotericin B given in either lipid emulsion or dextrose showed no significant difference, but both groups showed a lower incidence of amphotericin B intolerance in comparison with the adult series. The inability to reduce toxicity of amphotericin B by simple mixing with lipid emulsion has led to increasing use of commercially available lipid formulations of amphotericin B.

Amphotericin B↗
PubMedDate not supplied

The architecture of interphase chromosomes and nucleolar transcription sites in plants.

Fluorescence in situ hybridization (FISH) coupled with confocal microscopy has been used to reveal the interphase chromosome organization in plants. In wheat and several other related species, we have shown that the interphase chromosomes are in a very well-defined organization, with centromeres and telomeres located at opposite sides of the nuclear envelope-a classic Rabl configuration. In transgenic wheat lines, FISH analysis of metaphase chromosomes has shown that multiple transgene copies can be integrated along a single chromosome, with large regions of intervening genomic sequence. These multiple copies are often colocalized in interphase, suggesting either an ectopic association or a highly reproducible interphase chromatin configuration. Bromo-uridine (BrU) incorporation has been used to label transcription sites in the nucleolus. Using pea root tissue, we have combined BrU incorporation with preembedding 1-nm gold detection to image the nucleolar transcription sites by electron microscopy. This has revealed many distinct elongated clusters of silver-gold particles. These clusters are 200-300 nm in length and are thicker at one end than the other. We suggest that each cluster corresponds to a single transcribed gene. Serial sectioning of several entire nucleoli has enabled the reconstruction of all the nucleolar transcription sites, and we have estimated that there are 200-300 transcribed genes per nucleolus.

Bromodeoxyuridine↗
PubMedDate not supplied

Intermittent 20q- and consistent i(7q) in a patient with Shwachman-Diamond syndrome.

Shwachman Diamond syndrome (SDS) is a genetic disorder characterized by pancreatic hypoplasia, recurrent infection and bone marrow dysfunction. Some cases have an abnormality of chromosome 7, such as isochromosome 7q (i(7q)), which may be associated with the development of leukemia. We present a boy who was diagnosed with SDS at 19 months of age. From age 5-14 years, bone marrow cytogenetics has shown a consistent abnormality - i(7q), with an intermittent separate abnormality - deletion 20q, from age 11 years. During this time, the boy has been clinically well without leukemic signs, managed conservatively. We suggest that deletion 20q may be a non random secondary change in SDS with i(7q).

Bone Marrow Diseases↗