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R Bell

Publications and source records attributed to R Bell.

At least 163 records · Page 9Linked to original sources
PubMed1995

Comparison of the positional cloning methods used to isolate the BRCA1 gene.

A critical step in positional cloning is the identification of candidate genes from a large, genetically defined region. Candidate gene isolation by hybrid selection, genomic sequencing, and direct cDNA library screening identified 45 candidate gene fragments (CGFs) from a 600 kb genomic region that contains the BRCA1 gene. These CGFs define a minimum of 15 genes, six of which are newly localized to the BRCA1 region. We present an analysis of the efficiency and the sequences generated for each of these methods. We also compare our CGF set to those reported for the BRCA1 region by three other groups, revealing a surprising lack of overlap among the sets.

Breast Neoplasms↗
PubMed1995

Correlation of p-glycoprotein detection by immunohistochemistry with mdr-1 mRNA levels in osteosarcomas. Pilot study.

All the factors that influence prognosis in patients with osteosarcomas have not been fully determined. One reported predictor of poor outcome is increased multi-drug resistant gene (mdr-1) expression, as measured by reverse transcription and polymerase chain reaction (RT-PCR). We examined whether immunostaining for p-glycoprotein, the protein product of mdr-1, could be used instead of RT-PCR to indicate the presence of the multidrug-resistant phenotype. The sensitivity of the immunostaining was determined using KB cell sublines. For 13 cases of osteosarcoma, samples were immunostained for p-glycoprotein and the levels of mdr-1 expression quantitated with use of RT-PCR. Three osteosarcomas with undetectable levels of mdr-1 expression by RT-PCR were negative immunohistochemically. Ten cases showed mdr-1 expression ranging from approximately 1 to 32 copies of mdr-1 mRNA/cell. Of these cases, five cases contained occasional tumour cells with positive immunostaining. There was no correlation between levels of expression and the presence or number of immunoreactive cells. These results indicate that the presence of p-glycoprotein immunostaining does not reliably correlate with the level of mdr-1 expression. However it may be useful in conjunction with RT-PCR to further define different subgroups of osteosarcomas that may have different prognoses, and this is currently under investigation.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

A method for the treatment of ureteric complications following renal transplantation.

Over an 8-year period, 117 renal transplants (97 cadaveric and 20 living related) were performed at the Sir Charles Gairdner Hospital, Perth, Western Australia, Australia. Ureteric complications following renal transplantation occurred following seven transplants (6%). The technique of using a multiply fenestrated vesicocutaneous stent/drain to manage this problem is described. This was uncomplicated in all cases with the exception of one case in which the stent/drain was removed early because of blockage and sepsis, but most importantly on no occasion was the graft lost. We therefore recommend this technique for the management of this complication, whether early or late. We observed a disproportionate number of ureteric complications in living related transplants, a feature not described previously.

Adult↗
PubMed1995

Fetal fibronectin in the cervicovaginal fluid of women with threatened preterm labour as a predictor of delivery before 34 weeks' gestation.

Fetal fibronectin (fFN) is an extracellular matrix protein found at the junction between fetal and maternal tissue. It has been hypothesized that fFN is released into cervicovaginal fluid prior to the onset of preterm labour and during episodes of threatened preterm labour (TPL). In the present study fFN was present in the cervicovaginal fluid of 31% (11/36) of patients with TPL. The presence of fFN was found to be predictive of delivery prior to 34 weeks' gestation in 36 patients presenting with TPL and intact membranes (sensitivity 100%, specificity 81%). Eleven patients had a positive fFN assay and 5 delivered before 34 weeks (positive predictive value (PPV) 46%). Twenty-five patients had a negative fFN result and none were delivered before 34 weeks (negative predictive value (NPV) 100%). Patients presenting with TPL who are fFN positive would be ideal candidates for intervention trials of tocolytics. It may be possible to delay or avoid immediate tocolysis and interhospital transfer in patients with a negative fFN immunoassay.

Body Fluids↗
PubMed1995

Do childbirth classes influence decision making about labor and postpartum issues?

This study investigated the role of childbirth education for women attending the Royal Women's Hospital Family Birth Center, Melbourne, Australia, in relation to making decisions about breastfeeding, pain medication, and length of hospital stay. Fifty-nine primiparous women completed a questionnaire after delivery about the influence of childbirth education classes on their decisions during pregnancy, birth, and the postnatal period. The results indicated that although the women enjoyed childbirth education classes, the information they received had minimal effect on their decision to breastfeed and the appropriateness of a 24-hour stay. Information gained about the use of pain medication in labor was clearly helpful when women made decisions about pain relief. Educational strategies have failed to address the tendency of nulliparous women to postpone making decisions about the postnatal period such as early discharge, and further investigation on this aspect of a childbirth education program is suggested.

Adolescent↗
PubMed1995

The prevalence of prodromal features of schizophrenia in adolescence: a preliminary survey.

In most cases of schizophrenia the onset of frank psychosis is preceded by a period of prodromal features. This period has been relatively neglected by researchers and is potentially important in promoting early intervention. The prevalence of DSM-III-R schizophrenia prodrome symptoms was assessed as part (n = 657) of a large (n = 2525) questionnaire-based survey of high school students. Individual symptoms were highly prevalent and the prevalence of DSM-III-R prodromes ranged from 10 - 15% to 50%. Despite methodological weaknesses, the data suggest that DSM-III-R prodromal features are extremely prevalent among older adolescents and unlikely to be specific for subsequent schizophrenia. Clinically these features cannot be regarded as sufficient evidence of early schizophrenia and more accurate predictors of incipient schizophrenia need to be defined.

Adolescent↗
PubMed1995

Radiological predictors of response to renovascular reconstructive surgery.

The aim of this study was to identify preoperative angiographic criteria which could be used to predict the response to renovascular reconstruction. A cohort of 49 patients who survived for more than 6 months after renovascular reconstruction was studied. All preoperative angiograms were reviewed independently and the renal size, degree of stenosis and the length of the lesion recorded. The response of blood pressure and renal function to surgery were correlated with the angiographic findings. We found that 58% of patients had long-term improvement in blood pressure control, though the response was significantly better where both kidneys were >12 cm in size (82%) compared with when both kidneys were < 12 cm (25%), P < 0.02. The degree of stenosis, while showing a trend towards a better blood pressure response with increasing stenosis, was not a statistically significant factor. None of the angiographic criteria examined could be used to predict the response in renal function. We have shown that the preoperative renal size is the only angiographic factor that may have some role in predicting the response of blood pressure to renovascular reconstruction.

Adult↗
PubMed1995

Development of a cervical cancer education program for native American women in North Carolina.

The North Carolina Native American Cervical Cancer Prevention Project is a five-year, NCI-funded public health education program. The project was developed to address the problem of excess mortality from cervical cancer among Native American women by increasing screening and follow-up of abnormal cervical smears. This paper describes the process of developing and implementing the intervention, an individualized health education program. Development of the intervention was guided by the health belief model, social learning theory, self efficacy theory, and PRECEDE, a planning model. Community analysis revealed that the target populations had limited awareness of cervical cancer as a specific type of cancer, and had an experientially-based pessimistic outlook regarding survival with cancer. Steps in developing the cervical-cancer prevention program included 1) development of objectives, 2) selection of strategies and development of cervical cancer education materials, 3) pretesting and revision, and 4) implementation, monitoring, and further revision. Native American lay health educators were recruited and trained to deliver the program. The experience of developing and implementing the individualized health education program suggests that the design of health education programs for Native Americans should begin with examination of basic assumptions regarding the nature of health and illness in the target population. The unique cultures and the diversity of Native American populations are critical factors in the development of health education programs for them.

Adolescent↗
PubMed1995

Attitudes and behaviors of African-American and Mexican-American women delivering newborns in inner-city Los Angeles.

To study some of the factors relating to the care of mothers and newborns in an inner-city hospital, three sources of information were reviewed: an obstetric database including information on prenatal care and perinatal mortality, a database of all admissions to the hospital neonatal intensive care unit over the past 5 years, and a detailed questionnaire concerning attitudes and behaviors of recently delivered women. While analyses from these hospital-based data are not conclusive, the results add evidence for the following propositions: 1) Optimal prenatal care is infrequently obtained by mothers delivering at inner-city hospitals. Lack of prenatal care is clearly associated with increased perinatal mortality. While the need for prenatal care is appreciated by 98% of the mothers in this sample, the most frequent reasons why prenatal care is not obtained earlier or more frequently involve knowledge about and access to prenatal care. 2) Inner-city mothers, in general, manifest attitudes and behaviors that promote the welfare of their pregnancies and newborns. These attitudes and behaviors are in stark contrast to those that are frequently attributed to inner-city women by the media. 3) Acute perinatal medical and nursing care are perceived by many postpartum women as suboptimal, particularly in terms of the lack of respect shown to patients by nurses and doctors. 4) Improved acute obstetric and neonatal care improves perinatal morbidity and mortality of infants delivered at inner-city hospitals.

Adult↗
PubMed1994

Metastatic behavior of the RIF-1 murine fibrosarcoma: inhibited by hypophysectomy and partially restored by growth hormone replacement.

BACKGROUND: We recently demonstrated that hypophysectomy profoundly inhibits metastatic behavior in the MGH-OGS murine osteosarcoma model and speculated that this effect is related at least in part to ablation of the growth hormone (GH)-insulin-like growth factor I (IGF-I) axis. PURPOSE: In this study, we determined whether the administration of GH to animals rendered GH and IGF-I deficient by hypophysectomy attenuates the inhibitory effects of hypophysectomy on metastatic behavior. METHODS: Metastatic behavior was assayed by counting visible metastases in lungs 3 weeks after tail vein injection of RIF-I fibrosarcoma cells to control mice (n = 29), hypophysectomized mice (n = 19), and hypophysectomized mice administered 0.05 microgram/g body weight recombinant human GH twice daily (n = 21). RESULTS: Twenty of 21 hypophysectomized mice receiving GH, eight of 19 hypophysectomized mice not receiving GH, and 26 of 29 controls had grossly visible pulmonary metastases 3 weeks after intravenous injection of 5 x 10(5) cells; mean numbers +/- SD of gross metastases were 38.4 +/- 11.3, 6.4 +/- 2.2, and 13.1 +/- 2.8 in the three groups, respectively. The presence (P < .005, chi-square test) and number (P = .0003, Mann-Whitney U test) of metastases were significantly reduced in hypophysectomized hosts compared with control hosts and were significantly higher in hypophysectomized, GH-replaced hosts compared with hypophysectomized hosts (P < .001, chi-square test; P = .011, Mann-Whitney U test), while the difference in presence and extent of metastases between control and hypophysectomized, GH-replaced hosts was not statistically significant. CONCLUSIONS: These data support the hypothesis that the status of the host with respect to GH and/or GH-dependent factors such as IGF-I influences the metastatic behavior of certain neoplasms. IMPLICATIONS: Our results raise the possibility that compounds that reduce GH output or interfere with GH action, such as somatostatin analogues, GH antagonists, IGF antagonists, and GH-releasing hormone antagonists, may suppress metastatic behavior of certain neoplasms.

Animals↗
PubMed1994

Primary non-Hodgkin's lymphoma of bone. A clinicopathologic study.

BACKGROUND: This study relates our experience in the diagnosis and treatment of a rare clinical entity, non-Hodgkin's primary lymphoma of bone. METHODS: Seventeen cases of patients with primary lymphoma of bone diagnosed and treated at a single institution between 1975 and 1992 are reviewed. Ten patients received combined-modality therapy, consisting of an anthracycline-containing combination chemotherapy (CT) regimen, followed by adjuvant radiotherapy (RT) to the primary site of disease. Five patients were treated with CT alone; one patient received RT alone; and one patient was treated with CT after emergency RT for spinal cord compression. RESULTS: Thirteen patients presented with Stage I disease, two with Stage II; and two with Stage IV disease (multiple bony sites only). Thirteen patients had an intermediate-grade diffuse large cell lymphoma; two had an intermediate-grade mixed small and large cell lymphoma; and two had a high-grade lymphoma (one immunoblastic and one small non-cleaved cell lymphoma). The overall response rate was 94% (18% complete response, 58% partial response 1, and 18% partial response 2). Thirteen patients are alive and disease-free at a median of 29 months; 10 of these received CT+RT, and 3 received CT alone. Three patients have died; one of these received CT+RT and one CT alone, and one relapsed immediately after CT. One patient, who was initially treated with RT and then with CT+RT after relapse, was lost to follow-up 40 months from the start of treatment. CONCLUSIONS: Because experience in the literature suggests a 50% distant relapse rate in primary lymphoma of bone treated with RT alone, our policy is to treat all patients with combined-modality therapy (CT+RT). However, only a Phase III randomized, controlled clinical trial will determine whether CT+RT is superior to either modality alone.

Adolescent↗
PubMed1994

Histological necrosis in soft tissue sarcoma following preoperative irradiation.

Forty-eight patients with soft tissue sarcomas that presented adverse features for treatment by limb salvage surgery and postoperative irradiation were treated by preoperative irradiation and surgery using a consistent protocol. Following resection, the extent of histological necrosis in the specimen was scored according to the criteria of Willet et al. Of the 48 cases, 16 (34%) demonstrated Grade 1 response (< 50% necrosis), 15 (31%) Grade 2 (50-80% necrosis), and 17 (35%) Grade 3 (> 80% necrosis). There was a trend toward more extensive necrosis in liposarcoma tumors (53% showing Grade 3 response compared to 26% of other sarcomas). Logistic regression analysis demonstrated a significant relationship between necrosis and tumor size (P < 0.001) with larger tumors having higher grades of necrosis. Tumor grade did not seem to affect the extent of necrosis. In comparison to the previous report of necrosis in soft tissue sarcoma following irradiation, the current analysis revealed a smaller proportion of tumors with Grade 3 necrosis.

Adult↗
PubMed1994

Effects of adding an Italian theme to a restaurant on the perceived ethnicity, acceptability, and selection of foods.

We investigated whether a change in the perceived ethnicity of a food can be produced without manipulating the food item itself, and if that change in ethnic perception is accompanied by a change in acceptability and food selection behavior. Italian and British foods were offered in a British restaurant for four days. Foods were offered for 2 days under control conditions, when the restaurant was decorated as usual. The identical foods then were offered in the restaurant for 2 more days under experimental conditions, when ethnic names were used on the menu to describe foods, and the restaurant was decorated with an Italian theme. Perceived ethnicity and acceptability of items were rated by customers each day, and item selection was tracked. The Italian theme increased selection of pasta and dessert items, and decreased the selection of fish. The Italian theme also increased the perceived Italian ethnicity of British pasta items, fish and veal, and increased the perceived Italian ethnicity of the meal overall. These findings show that changes in perceived ethnicity and food selection can be accomplished without altering food items, but merely by manipulating the environment, and may imply a unique strategy for increasing perceived menu variety.

Culture↗
PubMed1994

Role of sensory and cognitive information in the enhancement of certainty and liking for novel and familiar foods.

Expected and actual liking for novel and familiar foods were examined under various conditions of sensory and verbal information with 121 subjects who differed in food neophobia. The possible mediating roles of uncertainty about product identity and resemblance to familiar foods were also investigated. Subjects were divided into three verbal information groups (no information; product name; ingredient and use information) balanced for neophobia, age and gender. All groups rated test samples under three sensory conditions: (1) appearance only, (2) appearance and smell and (3) appearance, smell and taste. Neophilics rated novel foods more favorably than did neophobics. Accumulating sensory experience (appearance, smell, taste) decreased liking for novel foods but increased liking for familiar foods. Verbal information generally increased liking for all samples. Liking and certainty of product identity were curvilinearly related for novel foods, but linearly related for familiar foods. Liking for products judged to closely resemble the test product predicted up to 64% of the variability in expected and actual liking. Eight weeks later, subjects rated one of the two novel foods higher than in the first exposure, but no other exposure effects were observed. Our data suggest that information (possibly via reduced uncertainty), resemblance to more familiar foods, and exposure contribute to reducing initially negative responses to novel foods; furthermore, neophobia decreases liking for novel foods similarly at all levels of sensory input (visual, smell and taste).

Adult↗
PubMed1994

Efficacy and safety of 0.5% podofilox solution in the treatment and suppression of anogenital warts.

PURPOSE: For the patient-administered treatment of anogenital warts, 0.5% podofilox (podophyllotoxin), one of the active compounds of podophyllin, has been shown to be more effective than the vehicle alone. This study was designed to evaluate the safety and efficacy of 0.5% podofilox treatment followed by prophylaxis. PATIENTS AND METHODS: A total of 103 patients were entered in stage 1 of the study. Stage 1 was an open label study, and patients self-administered 0.5% podofilox twice daily for 3 consecutive days per week for 4 weeks. A total of 100 patients remained available for efficacy and safety analyses. At the end of stage 1, patients who had a complete response proceeded to stage 2 of the study. Patients who had a 50% to 99% reduction in measured total wart area were offered cryotherapy every 10 days, up to 5 times. If cleared of warts, they were also entered into stage 2. A total of 57 patients were enrolled into stage 2, a double-blind, randomized, placebo-controlled prophylactic study of 0.5% podofilox self-administered once daily for 3 days per week for 8 weeks, on the sites of healed warts. A total of 45 patients in stage 2 were available for efficacy analysis. RESULTS: By the end of stage 1, 68% of the warts had disappeared, and 29 of 100 patients (29%) had a complete response. A total of 49 patients had a 50% or greater improvement in wart area and underwent cryotherapy. Rates of local side effects after 1 week of treatment were 57% for inflammation, 39% for erosion, 47% for pain, 48% for burning, and 44% for itching. However, these symptoms and signs were mostly mild to moderate in intensity and diminished over time. Therefore, overall treatment was well tolerated. In stage 2, only 4 of 21 patients (19%) in the podofilox group experienced a recurrence as opposed to 12 of 24 (50%) in the placebo group (P = 0.031). As in stage 1, the side effects were modest, and the drug was well tolerated. CONCLUSION: This study confirms the efficacy and good tolerance of 0.5% podofilox in the treatment of anogenital warts. It also establishes the safety and superior efficacy of patient-administered podofilox over the vehicle alone as prophylaxis against recurrence of lesions. Although long-term efficacy and tolerance remain to be established, podofilox appears to be a useful agent in the control of this disease.

Adult↗