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Abstract
BACKGROUND Although there is evidence for a reduction in breast carcinoma mortality with mammographic screening, some doubts have been expressed, and there is still uncertainty regarding the age specific effects. METHODS The authors report on a randomized, controlled trial of mammographic screening for breast carcinoma that was conducted among 51,611 women (21,650 women who were invited to a screening [the study group] and 29,961 women in a control group) ages 39-59 years in Gothenburg, Sweden. Among women in the study group, the screening interval was 18 months. The screening phase of the trial took place in 1982-1991, and follow-up for breast carcinoma mortality continued until December 31, 1996. Mortality from breast carcinoma was analyzed using a Poisson regression model. Overall and age specific effects of invitation to mammography screening on breast carcinoma mortality were calculated. Three mortality effects were estimated: the effect on deaths from breast tumors diagnosed during the screening phase of the trial, as assessed by an independent Endpoint Committee (the EPC evaluation model); the effect on deaths from breast carcinoma diagnosed during the screening phase of the trial, as determined by data from the National Cancer Registry and the National Cause of Death Register (the SCB evaluation model); and the effect on deaths from all breast carcinomas diagnosed up to December 31, 1996, as determined by the National Cancer Registry and the National Cause of Death Register (the SCB follow-up model). RESULTS A nonsignificant, 21% reduction in the rate of mortality from breast carcinoma with invitation to screening was observed using the EPC evaluation model (relative risk [RR], 0.79; 95% confidence interval [95% CI], 0.58-1.08; P = 0.14); and a borderline significant, 23% rate reduction was observed using the SCB follow-up model (RR, 0.77; 95% CI, 0.60-1.00; P = 0.05). Age specific analyses yielded greater mortality rate reductions for the groups of women ages 39-44 years, 45-49 years, and 55-59 years, but there was no mortality rate reduction in the group of women ages 50-54 years. The effects of invitation to mammographic screening on the incidence of lymph node-positive disease closely paralleled the effects of invitation on breast carcinoma mortality. The effect on breast carcinoma mortality was consistent with the effect on all-cause mortality, suggesting no bias in classification of cause of death. Breast carcinoma incidence in the study group was almost identical to the incidence in the control group after trial by screening had ended in the control group (RR, 0.98; 95% CI, 0.88-1.09; P = 0.7). CONCLUSIONS The current results support the commonly observed 20-30% reduction in breast carcinoma mortality with invitation to screening. The impression that screening is less effective in women younger than 50 years may be an oversimplification. Age specific effects should be a target for further research.
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Abstract
This study investigates relationships between familial and hormonal risk factors and breast density in women at high risk of developing breast cancer. The subjects are a subset of 102 women from the international breast cancer intervention study (IBIS), for whom a series of repeated measurements of breast density were available. Details of familial and hormonal risk factors for breast cancer were collected at entry and multivariate ordered logistic regression used to identify risk factors for increased breast density. Lower body mass index and nulliparity were associated with high breast density, whereas smoking was associated with lower breast density. It is not yet known whether a reduction in breast density will lead to a corresponding reduction in breast cancer risk, so we propose that changes in breast density be investigated as a potential early indicator of efficacy in chemoprevention trials for breast cancer.
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104
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17. The use of radioiodine in the treatment of Gravesʼ hyperthyroidism in Tanzania. Nucl Med Commun 2002. [DOI: 10.1097/00006231-200212000-00028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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105
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Abstract
Prior alert via a landline telephone ("blue call") is commonly used to warn accident and emergency (A&E) departments of the impending arrival of a seriously ill or injured patient. There are no published indications for making such calls or validated protocols on message content. Submitted telephone information has the potential for distortion as it is passed through the control centre resulting in inappropriate resource allocation. This study focuses on the quality and content of the message in the context of the available patient details as well as reviewing the clinical indications for the call. Data were collected on patients for whom "blue calls" were made to an A&E department over three months of 1998. Patients with life threatening conditions who were brought by non-blue light ambulance were identified during the same period. Similar details were collected on these critical patients. Of the 189 "blue calls" with complete details, 73% were admitted, (12% to ITU) and 18% died. Sixty nine per cent of cases were medical, 26% trauma and 5% obstetric. Pre-hospital observations were missing for 25% of patients (excluding patients in cardiac arrest), suggesting that the decisions to make a pre-alert call may have been based on subjective criteria in a significant minority. Information given over the telephone invariably included age, sex and presenting complaint but details of the current condition of the patient were included in only 11%. On reviewing pre-hospital information, a consultant in A&E and an ambulance paramedic judged that a prior alert was justified in 93% but additional information would be helpful in 52% of cases to correctly mobilise resources. Seventy five "clinically critical" patients were found in the three months of the study. Clinically critical patients were patients who had no prior alert, transported by ambulance, who were subsequently admitted to intensive care, theatre, or other high dependency areas. They included 27 patients with symptoms of a myocardial infarction. These patients may have benefited from prior alert. A protocol is suggested to provide criteria for making a prior alert to the A&E department via a landline connection. A standardised message structure would be used using vital signs and mechanism of injury or type of illness to assist in hospital preparation.
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106
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Challenging the precepts of family-centered care: testing a philosophy. PEDIATRIC NURSING 2000; 26:625-32. [PMID: 12026366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Family-centered care (FCC) is a model of patient care delivery that encourages the inclusion of the family in the planning and provision of care. Although this model has been discussed extensively in the literature and adopted by some institutions, it is one that many have difficulty implementing. The purpose of this study was to test the elements of a FCC philosophy developed for maternal/child units at a major medical center. Questionnaires developed for this study and translated into four languages were completed by 193 parent/patient participants. The questionnaire asked participants to rate the importance of FCC interventions and report which interventions had been provided. Most of the participants were Caucasian, married, female, had an annual income of $20,000 or less, had 12 or fewer years of education, and were younger than 40 years of age. Overall, "feeling welcome when I come to the hospital" was the highest rated item by parents of hospitalized neonates and children and perinatal patients. Findings from this study will be used to implement a FCC care philosophy.
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How much to do at the accident scene? Paramedic agrees with most of comments about prehospital care. BMJ (CLINICAL RESEARCH ED.) 2000; 320:1005-6. [PMID: 10753163 PMCID: PMC1117878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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108
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Functional brain imaging and pharmacotherapy in social phobia: single photon emission computed tomography before and after treatment with the selective serotonin reuptake inhibitor citalopram. Prog Neuropsychopharmacol Biol Psychiatry 2000; 24:419-38. [PMID: 10836490 DOI: 10.1016/s0278-5846(99)00109-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
1. Despite increased understanding of the prevalence and pharmacotherapy of social phobia (or social anxiety disorder), the neurobiology of the disorder is little understood. 2. Little data exists on the effect of pharmacotherapeutic intervention on regional cerebral blood flow (rCBF) in this disorder. Patients (n=15) who met DSM-IV diagnostic criteria for social phobia were subjected to single photon emission computed tomography (SPECT) with technetium-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) before and after an eight-week trial of pharmacotherapy with the selective serotonin reuptake inhibitor (SSRI) citalopram. 3. Pharmacotherapy led to significantly reduced activity in the anterior and lateral part of the left temporal cortex; the anterior, lateral and posterior part of the left mid frontal cortex; and the left cingulum. 4. Despite the small sample size, medication non-responders (n=6) had higher activity at baseline in the anterior and lateral part of the left temporal cortex and the lateral part of the left mid frontal regions compared with responders (n=9). These data from this exploratory study are consistent with work suggesting that the anxiety disorders share certain mediating neurocircuitry, although activity in other brain regions may differ. 5. Further research is necessary to determine the neurobiological underpinnings of social phobia.
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Single photon emission computed tomography of the brain with Tc-99m HMPAO during sumatriptan challenge in obsessive-compulsive disorder: investigating the functional role of the serotonin auto-receptor. Prog Neuropsychopharmacol Biol Psychiatry 1999; 23:1079-99. [PMID: 10621951 DOI: 10.1016/s0278-5846(99)00051-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
1. Symptoms of obsessive-compulsive disorder (OCD) may be acutely exacerbated by administration of certain serotonin agonists Exacerbation of OCD symptoms by sumatriptan, a 5HT1D agonist (Zohar, 1993), is consistent with pre-clinical data suggesting that the serotonin auto-receptor plays an important role in this disorder (El Mansari et al, 1995). 2. In order to investigate the functional role of the serotonin auto-receptor in OCD, the authors undertook single photon emission computed tomography in OCD patients after administration of sumatriptan and placebo. The authors hypothesized that, as in the case of m-chlorophenylpiperazine (mCPP) challenge (Hollander et al, 1995), exacerbation of OCD symptoms would be accompanied by increased cortical metabolism and thus blood flow, and more specifically by increased activity in the orbitofrontal-striatal circuit. They also expected, that as in the case of mCPP challenge (Hollander et al, 1993), exacerbation of OCD symptoms would be associated with a relatively poor response to subsequent treatment with serotonin specific reuptake inhibitors. 3. Sumatriptan (100 mg orally) and placebo were administered on separate days to 14 patients who met DSM-IV diagnostic criteria for OCD, using a randomized double-blind design. After 90 minutes, patients were injected with Tc-99m HMPAO and underwent single photon emission computed tomography (SPECT) of the brain. Activity in regions of interest was calculated, and compared using repeated measures analysis of variance. Patients were subsequently treated with a serotonin specific reuptake inhibitor (SSRI). 4. Behavioral response to sumatriptan was heterogenous, with 4 patients showing acute exacerbation, and 4 patients demonstrating a decrease in symptoms. On sumatriptan challenge, there was a significant association between symptom exacerbation and decreased activity in frontal areas. There was an association between decreased activity in an inferior frontal area with worse response to treatment, and also patients with symptom exacerbation after sumatriptan had poorer response to SSRI treatment. 5. Heterogeneity of behavioral response to sumatriptan in OCD is consistent with previous studies demonstrating conflicting and heterogenous behavioral responses to serotonergic challenges (Hollander et al, 1992), and with underlying heterogeneity in the neurobiology of this disorder. 6. It may be hypothesized that increased frontal activity in some patients with OCD is itself a compensatory mechanism. In patients with such compensatory hyperactivity, administration of a serotonin auto-receptor agonist results in decreased frontal activity and exacerbation of OCD symptoms. These patients may also be less likely to respond to treatment with a SSRI. 7. Further work combining pharmacological challenge paradigms and functional imaging techniques in OCD may be helpful in elucidating the neurobiology of this complex disorder.
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A randomised phase III cross-over study of tamoxifen versus megestrol acetate in advanced and recurrent breast cancer. Eur J Cancer 1996; 32A:1888-92. [PMID: 8943670 DOI: 10.1016/0959-8049(96)00191-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
139 peri- and postmenopausal women with advanced or recurrent breast cancer who had not received prior hormonal therapy were randomised in an open, cross-over study comparing the synthetic progestogen megestrol acetate with tamoxifen. The response rate (CR/PR) to megestrol acetate (25%; 95% confidence interval (CI) 15-35%) was not significantly different from that produced by tamoxifen (33%, CI 22-44%). Time-to-treatment failure was also similar in the two groups. Cross-over treatment was given on progression in 76 cases. Cross-over response (CR/PR) was seen in 3 of 35 patients (9%) receiving megestrol acetate as second-line therapy and in 6 of 41 patients (15%) receiving tamoxifen second-line. There was no significant difference in survival between the groups (P = 0.17) with median survival times of 24 and 32 months for the megestrol acetate and tamoxifen groups, respectively. The toxicity profile of the two drugs was different, although significant toxicity was rare with either agent. Megestrol acetate is an effective treatment for advanced breast cancer in older women when used either as first- or second-line treatment. Cross-over response is seen following both treatments. Given that most patients now receive tamoxifen as adjuvant treatment, megestrol acetate would appear to be one of the logical choices for patients who find the side-effects of tamoxifen unacceptable and for those who relapse on tamoxifen with further hormone therapy being clinically indicated.
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112
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The prognostic significance of Bcl-2 and p53 expression in ovarian carcinoma. Cancer Res 1996; 56:2178-84. [PMID: 8616869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Advanced ovarian cancer is characterized by poor prognosis and the development of resistance to chemotherapy. We have found that Bcl-2 and p53, two proteins implicated in the control of apoptosis, are differently expressed in the ovarian cell line A2780 and its cisplatin-resistant variant 2780CP, with the resistant line overexpressing both proteins. Transfection of the A2780 cells with a Bcl-2- or p53-expressing plasmid increases resistance to various drugs, including cisplatin, suggesting that Bcl-2 and p53 expression may influence the sensitivity of ovarian cancer cell lines to chemotherapy. Expression of these two proteins in vivo was determined by immunohistochemical staining of ovarian tumor biopsies from 70 patients. We found that Bcl-2 and p53 were expressed in 57 and 61% of specimens examined, respectively. Both p53 and Bcl-2 were found to be independent prognostic indicators of survival in ovarian cancer. Survival was poorer in patients with tumors expressing high levels of p53, whereas expression of Bcl-2 was associated with improved survival.
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113
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Abstract
The data from two prospective randomised phase III trials that were initiated by the West Midlands Ovarian Cancer Study Group (WMOCSG) in 1981 and 1986, recruiting 167 and 195 patients respectively, have been pooled and the survival patterns of the 362 patients treated for advanced epithelial ovarian cancer within clinical trials in the West Midlands over the 10 year period (1981-91) have been explored. All patients had histologically proven epithelial ovarian cancer and all had residual disease after primary surgery, with the majority having stage III/IV disease. The primary treatment for all patients was debulking surgery followed by platinum-based chemotherapy. Eligible patients were further randomised to undergo a second debulking operation. The main end point, survival, was assessed using Kaplan-Meier curves and the log-rank test. A Cox proportional hazards model identified performance status (P = 0.002), residual disease (P = 0.005) and albumin level (P = 0.04) as independent prognostic factors. A multivariate model to predict survival curves for patients with the best and worst prognoses was developed with predicted 5 year survival of 30% and 3% for those in the best and worst prognostic groups respectively. The identification of clinical interventions to improve outcome is an urgent matter since the prognosis for patients with advanced ovarian cancer remains poor.
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Management of ventricular fibrillation by doctors in cardiac arrest teams. Anaesthetists are tested under examination conditions. BMJ (CLINICAL RESEARCH ED.) 1995; 310:1265-6. [PMID: 7767207 PMCID: PMC2549632 DOI: 10.1136/bmj.310.6989.1265c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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116
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Abstract
Levels of plasma cytokines and circulating endotoxin were assessed in 41 patients with severe intra-abdominal sepsis. Comparison was made with the Acute Physiology And Chronic Health Evaluation (APACHE) II scoring system. Blood samples were taken within 24 h of onset of the sepsis syndrome and at serial times thereafter. Increased levels of interleukin (IL) 6 (range 50-25,500 pg/ml) were detectable in all patients with sepsis. Eighteen of the 19 deaths were attributable to sepsis and higher levels of IL-6 at the onset of the sepsis syndrome correlated with a poor outcome. The sensitivity of IL-6 concentration in predicting mortality was 86.4 per cent with a specificity of 78.9 per cent and an overall correct classification rate of 82.9 per cent. IL-6 level was a better predictor than APACHE II score (sensitivity 72.7 per cent, specificity 57.9 per cent, correct classification rate 65.9 per cent). Levels of tumour necrosis factor alpha, IL-1 beta and endotoxin did not correlate with mortality rate. Plasma IL-6 concentrations may help in planning future strategies to decrease the mortality rate associated with sepsis.
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Intervention debulking surgery in advanced epithelial ovarian cancer. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1994; 101:142-6. [PMID: 8305389 DOI: 10.1111/j.1471-0528.1994.tb13080.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE To study whether intervention debulking surgery improves survival in patients with advanced ovarian cancer who have bulky (> 2 cm) residual disease after primary surgery. DESIGN A prospective multicentre randomised study. SETTING Hospitals in the West Midlands. SUBJECTS Ovarian cancer patients with bulky residual disease after primary surgery who are considered well enough to receive cis-platinum based chemotherapy and further surgery. METHODS Eligible patients were randomised to receive combination chemotherapy alone or combined with intervention debulking surgery. MAIN OUTCOME MEASURE Survival was assessed using product limit method and log-rank test. RESULTS Seventy-nine patients were entered into the study. Thirty-seven patients were randomised to intervention debulking surgery, 25 (67%) of whom underwent intervention debulking surgery, which was performed a median of 13 weeks after primary surgery. The median survival for the intervention debulking surgery group was 15 months (95% CI 10-20 mo) and that of those randomised to chemotherapy alone, which was 12 months (95% CI 8-16 mo), were not significantly different (hazard ratio = 0.71; 95% CI 0.44-1.13). CONCLUSION Intervention debulking surgery may not improve survival in patients with advanced ovarian cancer.
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Factors influencing blood transfusion during adult liver transplantation. Ann R Coll Surg Engl 1993; 75:339-44. [PMID: 8215151 PMCID: PMC2497978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
From 1982 to 1990, 300 adults received liver transplants in Birmingham UK with a median intraoperative blood transfusion rate of 23.5 units for the first 50 patients falling to 8 units for the last 50. The major factors in the reduction of blood usage were the experience of the team, the use of venovenous bypass and the use of an argon beam coagulator. Univariate analysis of preoperative factors in an attempt to predict patients at risk of excessive intraoperative transfusion showed that levels of serum sodium, urea, creatinine, haemoglobin, patient weight and the presence of ascites were significantly related to the quantity of blood transfused, although stepwise discriminant analysis showed that only blood urea and platelet count had an independent association with transfusion. The final model was poorly predictive of intraoperative transfusion requirements. Technical factors rather than patient-related factors are more important in the control of intraoperative bleeding in newly established transplant programmes.
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119
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Influence of timing of surgery during menstrual, cycle on survival of premenopausal women with operable breast cancer. Breast 1993. [DOI: 10.1016/0960-9776(93)90130-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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120
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Abstract
In a multicentre prospective randomized controlled trial, single agent cisplatinum was compared with whole abdomino-pelvic moving strip radiotherapy in the management of Stage IC-III epithelial ovarian cancer patients who had no macroscopic residual disease after primary surgery. Over a 6-year period 40 eligible patients were recruited, 15 of whom had Stage III disease. The overall 5-year survival was 60% with no significant survival difference between the treatment groups. Acute toxicity was common in both arms and six (11%) patients experienced significant long term disability.
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121
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Novel mutations in the pheA gene of Escherichia coli K-12 which result in highly feedback inhibition-resistant variants of chorismate mutase/prephenate dehydratase. Appl Environ Microbiol 1992; 58:2592-8. [PMID: 1514806 PMCID: PMC195826 DOI: 10.1128/aem.58.8.2592-2598.1992] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The bifunctional enzyme chorismate mutase/prephenate dehydratase (EC 5.4.99.5/4.2.1.51), which is encoded by the pheA gene of Escherichia coli K-12, is subject to strong feedback inhibition by L-phenylalanine. Inhibition of the prephenate dehydratase activity is almost complete at concentrations of L-phenylalanine greater than 1 mM. The pheA gene was cloned, and the promoter region was modified to enable constitutive expression of the gene on plasmid pJN302. As a preliminary to sequence analysis, a small DNA insertion at codon 338 of the pheA gene unexpectedly resulted in a partial loss of prephenate dehydratase feedback inhibition. Four other mutations in the pheA gene were identified following nitrous acid treatment of pJN302 and selection of E. coli transformants that were resistant to the toxic phenylalanine analog beta-2-thienylalanine. Each of the four mutations was located within codons 304 to 310 of the pheA gene and generated either a substitution or an in-frame deletion. The mutations led to activation of both enzymatic activities at low phenylalanine concentrations, and three of the resulting enzyme variants displayed almost complete resistance to feedback inhibition of prephenate dehydratase by phenylalanine concentrations up to 200 mM. In all four cases the mutations mapped in a region of the enzyme that has not been implicated previously in feedback inhibition sensitivity of the enzyme.
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122
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Abstract
The presence of parathyroid hormone related protein (PTHRP) in human breast cancers has been assessed by immunohistochemistry using a polyclonal antiserum specific for the mid-region sequence 37-67 in an immunoperoxidase technique. The primary tumours from 155 normocalcaemic, consecutive women with early breast cancer who had been followed up for a minimum of 5 years were assessed. Dewaxed paraffin sections of formalin fixed tissue was used throughout. Positive PTHRP staining was detected in 56% of the cancers and was unrelated to standard prognostic factors, recurrence or survival. However, PTHRP positivity was related to the development of bone metastases (P less than or equal to 0.03) and hypercalcaemic episodes. PTHRP is implicated as the humoral factor responsible for hypercalcaemia associated with breast cancer and tumour positivity may be a useful predictor of which women will develop bone metastases.
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The osteoclast functional antigen, implicated in the regulation of bone resorption, is biochemically related to the vitronectin receptor. J Cell Biol 1989; 109:1817-26. [PMID: 2477382 PMCID: PMC2115816 DOI: 10.1083/jcb.109.4.1817] [Citation(s) in RCA: 309] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We have defined the structure of the Osteoclast Functional Antigen (OFA) by immunological and biochemical means. OFA is an abundant surface antigen in human and animal osteoclasts and has been characterized previously by monoclonal antibodies 13C2 and 23C6, one of which mimicks the inhibitory activity of calcitonin on osteoclastic bone resorption. By the following criteria we show that OFA is a member of the integrin family of extracellular matrix receptors and is identical, or at least highly related, to the vitronectin receptor (VNR) previously isolated from placenta and melanoma cells. Immunoprecipitation analysis demonstrates that OFA from osteoclasts and a monkey kidney cell line Vero is a heterodimeric molecule of 140 kD (alpha chain) and 85 kD (beta chain) under nonreducing conditions; on reduction at least one low molecular mass (alpha') species (of approximately 30-kD size) is released, resulting in a 120/100-kD dimer. Immunoblots of OFA isolated from osteoclasts and Vero cells and VNR purified from placenta and probed with heterosera to OFA and monoclonal antibodies to platelet gp111a (VNR beta chain) show immunological cross-reactivity between the alpha chains of OFA and VNR and the use of gp111a as a beta chain by both. OFA from Vero cells binds to an Arg-Gly-Asp containing peptide (GRGDSPPK) isolating a heterodimer recognized by anti-OFA monoclonal antibodies, 13C2 and 23C6. Immunohistochemical analysis showed a similar tissue distribution in humans for the antigen recognized by anti-OFA antibodies, a monoclonal antibody, LM142, raised to melanoma VNR, polyclonal antibodies to the placental VNR and a monoclonal antibody to the presumptive VNR beta chain, platelet glycoprotein 111a. Finally, NH2 terminal amino acid sequencing showed that the amino-terminus of the monkey alpha chain was identical in the 12 assigned residues to that of human VNR alpha chain. The beta chain sequence of OFA differed at least 1 (and up to 4) positions from platelet gp111a (VNR beta) in the first 18 amino acids sequenced. These, and other, data provide the first indication of a function for the VNR and suggest that cell-cell and cell-extracellular matrix interactions involving integrins may play an important role in bone physiology.
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Abstract
A porcine prorelaxin gene has been constructed partly by synthetic means and partly from its natural messenger RNA. A gene coding for the 32 N-terminal amino acids including a chain initiator methionine codon (B gene) was synthesised and inserted in a plasmid at a site downstream from a tryptophan promoter in such a way that its expression is under the control of the trp promoter. DNA corresponding to the rest of the prorelaxin was prepared using reverse transcriptase extension of a primer complementary to relaxin mRNA and joined at a suitable restriction site to the B gene. Transformation of E. coli with this plasmid followed by suitable induction resulted in the synthesis of a new protein identified as prorelaxin by its size and its antigenic similarity to relaxin.
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The graduate nurse. The nursing process studied in Toronto. NURSING MIRROR AND MIDWIVES JOURNAL 1977; 144:55-7. [PMID: 300157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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126
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MEDICAL CERTIFICATES OF INSANITY. West J Med 1853. [DOI: 10.1136/bmj.s3-1.52.1151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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