Search PubMed⌕ Search

Biomedical subjects

D K Webb

Publications and source records attributed to D K Webb.

33 records · Page 2Linked to original sources

Preventative policies in transfusion associated graft versus host disease in the treatment of cancer.

Experience of transfusion associated graft versus host disease (TA-GvHD) and current preventative policy in 22 UK children's cancer centres was established by questionnaire. Cellular blood products were irradiated in all centres during bone marrow transplantation, but there was no consensus for children receiving standard chemotherapy. Irradiation dose varied from 1500-5000 cGy and was below 2500 cGy in 12 units. Five cases of TA-GvHD were identified; all five children died.

Cancer Care Facilities↗

Hormonal regulation and expression of the jun-D protooncogene in specific cell types of the rat uterus.

Steroid hormone regulation and cell-type specific expression of the jun-D protooncogene in rat uterus was examined. Adult, ovariectomized rats were injected with progesterone, testosterone, 17beta-estradiol (E2-17beta), 16alpha-estradiol (E2-16alpha), dexamethasone or cycloheximide. Uteri were collected between 0 and 6 h post-treatment. Northern blot analysis of uterine RNA revealed that induction of jun-D was specific for estrogenic steroids, as progesterone and testosterone had no effect on expression of this member of the jun gene family. Treatment with E2-17beta increased jun-D mRNA levels by approx. 5-fold, with expression reaching peak levels at 3 h after treatment and declining thereafter. Administration of E2-16alpha, a short-acting estrogen that does not cause uterine cell proliferation, increased expression of jun-D but with different kinetics compared to the long-acting E2-17beta. The mRNA levels of jun-D increased by 3-fold 1 h after administration of E2-16alpha but declined soon after. Slight induction of jun-D mRNA by dexamethasone was apparent, but to a much lesser extent compared to estrogen. The protein synthesis inhibitor, cycloheximide, did not block jun-D induction, indicating that this is an "immediate early" response. Expression of Jun-D protein was examined by immunohistochemical methods. E2-17beta treatment activated jun-D primarily in the nuclei of luminal and glandular epithelial cells of the endometrium. These results demonstrate that hormonal induction of jun-D is specific for estrogens and that uterine expression of this protooncogene occurs in a cell-type specific manner.

Animals↗

Estrogen induces expression of c-jun and jun-B protooncogenes in specific rat uterine cells.

Expression of the protooncogene c-jun is induced in the uteri of ovariectomized rats in response to treatment with 17 beta-estradiol (E2-17 beta). E2 also specifically induces the uterine expression of jun-B-encoding mRNA. Medroxyprogesterone acetate and testosterone propionate treatment had no effect on the expression of c-jun- and jun-B-encoding mRNAs. Dexamethasone treatment, however, induced expression of c-jun mRNA, although less than that observed in response to E2. Cycloheximide treatment failed to block the E2-induced expression of c-jun and jun-B mRNAs, indicating that these were immediate early responses. E2-16 alpha, a short-acting estrogen, also induced c-jun and jun-B mRNA expression. The expression of c-Jun protein was examined by immunohistological methods and detected in all uterine cell types in response to treatment with estrogen. The Jun-B protein, however, was localized in uterine epithelial cells. The results of these experiments suggest that the cell type-specific expression of members of the jun family of protooncogenes may be an important regulatory event in the response of the uterus to estrogen.

Animals↗

A child with xeroderma pigmentosum and bone marrow failure.

The case of a child with both xeroderma pigmentosum and bone marrow failure is reported. It is suggested that this is not a chance association, and that the bone marrow hypoplasia may reflect an increased susceptibility of this patient's haemopoietic stem cells to non-UV mutagens.

Anemia, Aplastic↗

Acquired aplastic anaemia: still a serious disease.

Over 15 years, 42 children aged 2-14 years were diagnosed as having acquired aplastic anaemia. Adequate clinical details were available for 38 children who were categorised as very severe (n = 13), severe (n = 16), or nonsevere (n = 9) by the modified Camitta criteria. Treatment varied over the study period. Seven children received a bone marrow allograft from a full match family donor and three a matched unrelated donor transplant after failed treatment with antilymphocyte globulin. The remainder were treated with antilymphocyte globulin (n = 11), antilymphocyte globulin and oxymetholone (n = 4), oxymetholone with or without prednisolone (n = 12), or supportive treatment alone (n = 1). With a minimum follow up of one year since treatment, the five year survival was 70% for bone marrow transplantation with a family donor, 30% for antilymphocyte globulin, and 25% for oxymetholone. All three children with a matched unrelated donor transplant died. The prognosis of acquired aplastic anaemia remains poor for most children and new approaches to treatment are urgently required.

Adolescent↗

Estrogen induced expression of the C-jun proto-oncogene in the immature and mature rat uterus.

The expression of the proto-oncogene c-jun in response to estradiol treatment in immature and mature rat uterine tissue was measured using a cDNA encoding the mouse c-jun proto-oncogene. This probe hybridized to a major RNA band of 2.7 kb and a minor 3.2 kb band. In Northern blots of total RNA from both immature and mature rat uteri, estradiol treatment resulted in at least a 3 fold increase in expression of the 2.7 kb band over control levels by 3 hr post injection. By 12 hr post injection, expression of c-jun mRNA had returned to control levels. A strong induction (greater than 5 fold) of c-jun mRNA expression was also observed in stroma-myometrial tissue isolated from mature rats approximately 3 hours after treatment with estradiol. The similar kinetics of induction of c-fos and c-jun emphasizes the functional significance of the fos/jun heterodimer in control of uterine cell proliferation.

Animals↗

Systemic Salmonella infections in sickle cell anaemia.

Salmonella infections remain a significant cause of morbidity and mortality in patients with sickle cell disease. In Jamaica, 16 episodes of systemic Salmonella infection were recognized in 308 children with sickle cell disease followed prospectively in a cohort study from birth. There were eight cases with osteomyelitis, seven with septicaemia, and one with meningitis. Salmonella dactylitis was the commonest presentation of osteomyelitis in the young child. Comparison of clinical features between children with Salmonella dactylitis and dactylitis owing to avascular bone necrosis showed that children with osteomyelitis had significantly higher fever, prolonged history and fluctuant swellings. Fever above 38.5 degrees C occurred in four of five children with Salmonella dactylitis, but in only one of 59 with uncomplicated dactylitis (P = 0.01). Chloramphenicol and co-trimoxazole were both effective for systemic infection, and ampicillin alone was inadequate. Three deaths occurred, two from septicaemia and one from meningitis.

Adolescent↗

Gall stones in Jamaican children with homozygous sickle cell disease.

Gall stones were detected by ultrasonography in 30 of 226 (13%) children with homozygous sickle cell disease aged 5-13 years participating in a cohort study from birth. Children with gall stones had significantly lower total haemoglobin and fetal haemoglobin and higher bilirubin concentrations, but further analysis showed that the apparent effects of haemoglobin and fetal haemoglobin concentration were secondary to their relationship with bilirubin concentrations. Abdominal pain crises were significantly associated with gall stones but both factors appeared to reflect an increased clinical severity and were probably not causally related. No patients had symptoms specific of gall stones and an association with abdominal pain crisis should not, of itself, be considered an indication for surgery.

Adolescent↗

Self-help group meeting attendance among clients with dual diagnoses.

This study explores factors associated with self-help group meeting attendance in the aftercare of 81 clients with dual diagnoses of severe mental illness and chemical dependency following their discharge from an inpatient chemical dependency treatment program. It also explores the association between self-help group meeting attendance and treatment outcomes. Data were collected from patient records and results of the Addiction Severity Index (ASI) administered as part of an earlier experiment that evaluated the effectiveness of the treatment program. Collaterals also provided follow-up information. Of thirteen variables examined, only two were associated with increased self-help group meeting attendance: having more years of education and having a major substance problem that did not include alcohol. No association was found between self-help group meeting attendance and treatment outcome regarding psychiatric problem severity or five other domains of the ASI. A moderate association was found indicating that more self-help group meeting attendance was related to improvements in the legal problems domain of the ASI. Implications are discussed for future research and for improving self-help group meeting attendance and its influence on treatment outcomes for individuals with dual diagnoses.

Adolescent↗