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61.
62.
Parvovirus B19 in kidney transplant patients   总被引:1,自引:0,他引:1  
Renal transplant patients were screened for the presence of parvovirus B19, before transplantation and monthly for 4 months after transplantation, by means of a sensitive nested PCR assay. Upon screening plasma from 110 patients, we found that two asymptomatic patients were B19 DNA positive. One of these patients was PCR positive in the plasma sample taken 2 months after transplantation; the plasma contained anti-B19 IgG antibodies before transplant and throughout the follow-up period, with an increase in the IgG level in the second posttransplant sample coinciding with the detection of B19 DNA. IgM antibodies to B19 were not detected in this patient. Because, for this patient, the donor's spleen DNA was also B19 DNA positive, we suspect B19 transmission from the donor and limited B19 replication, inasmuch as this patient already had a primed immune response to B19. The other patient was PCR positive in the pretransplant and in the plasma sample taken 1 month after transplant and contained a strong anti-B19 IgG response in the pretransplant sample and throughout the follow-up period-and anti-B19 IgM antibodies were not detected before or after transplantation. By testing samples taken from this patient at 2 weeks, 2 months, and 3 months before transplantation, we were able to determine that the infection occurred shortly before transplantation. Unexpectedly, this graft failed and was removed 2 days after transplantation despite a negative cross-match. A pathological examination of the kidney indicated acute vascular rejection, suggesting a possible role for B19 in this complication.  相似文献   
63.
Infiltrating pleomorphic lobular carcinoma (PLC) is an aggressive variant of infiltrating lobular carcinoma. Recently, in situ changes identical to PLC (PLCIS) have been described. The role of prognostic markers and their correlation with therapeutics, clinical outcome, and genetic changes is not well established in PLC. The authors examined 38 cases of this entity to understand better this tumor's biology. Immunohistochemical (IHC) analysis was performed in 21 specimens for estrogen and progesterone steroid receptors, p53, Her 2 (p185), and GCDFP-15. Genomic deoxyribonucleic acid was obtained from microdissected tumor as well as normal control cells, and loss of heterozygosity was investigated at the ESR (16q24), p53 (TP53 17p), Her 2 (17q 11-12), and BRCA 1 (17q12-25) loci. In this series, the average patient age was 57.5 years (age range, 24-92 years). Twenty-seven women were postmenopausal. Tumor size ranged from 1.2 to 25 cm. Six patients were a pathologic stage I; 19, stage II; 12, stage III; and one, stage IV. Histologically, multifocal nodular aggregates of discohesive pleomorphic tumor cells were seen interspersed in dense and fibrotic breast parenchyma. Twenty-nine percent of the specimens demonstrated associated signet ring cells. The remainder had dishesive, globoid, plasmacytoid cells with high-grade nuclear features. PLCIS was identified in 17 of 38 patients (45%), and lobular carcinoma in situ (LCIS) was noted in 8 patients (21%). IHC analysis showed estrogen immunoreactivity in 81%, progesterone in 67%, GCDFP-15 in 71%, and Her 2 in 81% (2+ to 3+ membranous staining) of specimens. Antibodies to p53 stained the tumor cell nuclei in 48% of the tumors. Loss of heterozygosity was identified in 52% of the specimens at the p53 locus, 18% at the ESR locus, 19% to 24% at the Her 2 loci, and 27% to 32% at the BRCA 1 locus. Follow-up was available in 19 patients and ranged from 12 months to 15 years (mean, 73 months). Seven patients had no evidence of disease at last examination (range, 1-15 years), three patients were alive with disease (range, 2-14 years), and nine patients were dead of disease (range, 2 months-9 years). Six patients had subsequent diagnoses of tumor in the contralateral breast. Analysis shows that PLC tends to appear in older postmenopausal women who present with locally advanced disease. PLCIS was found to be associated with PLC 45% of the time. The aggressive clinical course of patients with PLC is supported by tumor immunoreactivity with unfavorable markers Her 2 and p53. Overexpression of Her 2 in PLC may be therapeutically relevant, enabling the use of novel chemotherapeutic drugs like Herceptin. Interestingly, tumors that were Her 2 immunoreactive also maintained estrogen hormone immunoreactivity.  相似文献   
64.
MVP chemotherapy (mitomycin C 8 mg m(-2), courses 1, 2, 4 and 6, vinblastine 6 mg m(-2), cisplatin 50 mg m(-2)) is an active low-toxicity regimen in non-small-cell lung cancer (NSCLC). Based on the single-agent activity of these agents in SCLC, we have conducted a phase II trial of MVP in SCLC. Fifty chemo-naive patients with SCLC were entered in this trial. There were 33 men and 17 women with median age 66 years (range 46-83 years); 18 patients had limited disease (LD) and 32 extensive disease (ED). WHO performance status (PS) was: three patients PS 0, 33 patients PS 1, ten patients PS 2, four patients PS 3. A maximum of six cycles was given in responding patients. On completion of chemotherapy, patients with LD obtaining complete response (CR)/good partial response (PR) received thoracic irradiation and those obtaining CR were offered entry into the ongoing MRC Prophylactic Cranial Irradiation Trial. The overall response was 79% with 17% CR and 62% PR. For LD patients, 38% obtained CR but for ED only one patient achieved CR. Median response duration for LD patients was 8 months and for ED patients 5 months. Median survival was 10 months for LD patients and 6 months for ED patients. There was complete resolution of symptoms in 24%, partial improvement in 68%, no change in 2% and progressive symptoms in 6%. As regards toxicity, 24% developed WHO grade 3/4 neutropenia, 16% grade 3/4 thrombocytopenia and 6% significant hair loss. Two patients died during the first week of treatment with neutropenic infection. Quality of life using the EORTC questionnaire (QLC-C30) with lung cancer module demonstrated significant improvements from baseline levels in emotional and cognitive functioning, global QOL, of pain, dyspnoea and cough. MVP, an effective palliative regimen for NSCLC, is also active against SCLC with low toxicity and merits comparison with more toxic conventional schedules.  相似文献   
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PURPOSE: Temozolomide, a DNA methylating agent used to treat melanoma, induces DNA damage, which is repaired by O6-alkylguanine alkyltransferase (ATase) and poly(ADP-ribose) polymerase-1 (PARP-1)-dependent base excision repair. The current study was done to define the effect of temozolomide on DNA integrity and relevant repair enzymes as a prelude to a phase I trial of the combination of temozolomide with a PARP inhibitor. EXPERIMENTAL DESIGN: Temozolomide (200 mg/m2 oral administration) was given to 12 patients with metastatic malignant melanoma. Peripheral blood lymphocytes (PBL) were analyzed for PARP activity, DNA single-strand breakage, ATase levels, and DNA methylation. PARP activity was also measured in tumor biopsies from 9 of 12 patients and in PBLs from healthy volunteers. RESULTS: Temozolomide pharmacokinetics were consistent with previous reports. Temozolomide therapy caused a substantial and sustained elevation of N7-methylguanine levels, a modest and sustained reduction in ATase activity, and a modest and transient increase in DNA strand breaks and PARP activity in PBLs. PARP-1 activity in tumor homogenates was variable (828 +/- 599 pmol PAR monomer/mg protein) and was not consistently affected by temozolomide treatment. CONCLUSIONS: The effect of temozolomide reported here are consistent with those documented in previous studies with temozolomide and similar drug, dacarbazine, demonstrating that a representative patient population was investigated. Furthermore, PARP activity was not inhibited by temozolomide treatment and this newly validated pharmacodynamic assay is therefore suitable for use in a proof-of-principle phase I trial a PARP-1 inhibitor in combination with temozolomide.  相似文献   
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Book reviews     
History

The End of History and the Last Man By Francis Fukuyama. Hamish Hamilton, London, 1992, 418 pp., £20.00, ISBN 0–24–1301–1

Aeskulap oder Mars? [Asdepius or Mars] (subtitle: Doctors against War) Edited by T.M. Ruprecht and C. Jenssen. (In German). Donat Verlag, Bremen, 1991, 604pp., 48.00DM, ISBN 3–924444–51‐X.

The Gulf War

Hidden Casualties, Volume II: The Environmental, Health and Political Consequences of the Persian Gulf War Edited by Saul Bloom, John M. Miller and Philippa Winkler, with Ross Mirkarimi. ARC/Arms Control Research Center, 942 Market St, Suite 202, San Francisco CA 94102, USA, 1993, 350pp.

Medicine and War

Wounded Healthy Cities: Searching for Health and Human Dignity A report by the Croatian Healthy Cities Network. Compiled by Ivana Eterovi?, Selma Sogori?, and Slobodan Lang. Edited by John Middleton. Sandwell Public Health Publications, 1992, PO Box 1953, Lyndon, West Bromwich, West Midlands, B71 4NA, pp. 68, £5.95 incl. p&;p, ISBN 0–9517035–4–4.

Public Health

Health through Public Policy, the Greening of Public Health Edited by Peter Draper. Greenprint, London, 1991, x + 258 pp., £9.99, ISBN 1–85425–045–0.

Economics

The Culture of Contentment By John Kenneth Galbraith. Sinclair Stevenson, London, 1992, 195pp., £14.95, ISBN 1–85619–147–8.

Beyond the Limits: Global Collapse or a Sustainable Future By Donella Meadows, Dennis Meadows and Jorgen Randers. Earthscan, London, 1992, xix + 300 pp., £19.95, ISBN 1–85383–130–1 (hbk), £11.95, ISBN 1–85383–131‐X (pbk).

Human Rights

Refugees: Rationing the Right to Life By David Keen. Zed Books, London, 1992, 86pp., £29.9S(hbk), ISBN 1–85649–091–2, £9.95(pbk), ISBN 1–85649–092–0.

Deadly Silence: Black Deaths in Custody Institute of Race Relations, London, 1991, 75pp., £4 (pbk), ISBN 085001–038–1.

Torture and Its Consequences: Current Treatment Approaches Edited by Metin Ba?o?lu. Cambridge University Press, Cambridge, 1992, xxiii + 527pp., £55.00, ISBN 0–521–39299–3

Militarism and the Environment

Taking Stock: The Impact of Militarism on the Environment Working Group on Militarism and the Environment. Science for Peace, 1992, 30pp., Can$ 4.00 (available from WGME, University College, University of Toronto, Ontario, Canada M5S 1A1).

AIDS

The AIDS Epidemic: Economic, Political and Security Implications By Alan Whiteside and David FitzSimons. Research Institute for the Study of Conflict and Terrorism, London, 1992, 43pp., £9.00, ISSN 0069–8792 (available from 136 Baker Street, London W1M 1FH)  相似文献   
69.
BACKGROUND AND PURPOSE:The National Institute of Neurological Disorders and Stroke common data elements initiative was created to provide a consistent method for recording and reporting observations related to neurologic diseases in clinical trials. The purpose of this study is to validate the subset of common data elements related to MR imaging evaluation of acute spinal cord injury.MATERIALS AND METHODS:Thirty-five cervical and thoracic MR imaging studies of patients with acute spinal cord injury were evaluated independently in 2 rounds by 5 expert reviewers. Intra- and interrater agreement were calculated for 17 distinct MR imaging observations related to spinal cord injury. These included ordinal, categoric, and continuous measures related to the length and location of spinal cord hemorrhage and edema as well as spinal canal and cord measurements. Level of agreement was calculated using the interclass correlation coefficient and kappa.RESULTS:The ordinal common data elements spinal cord injury elements for lesion center and rostral or caudal extent of edema or hemorrhage demonstrated agreement ranging from interclass correlation coefficient 0.68 to 0.99. Reproducibility ranged from 0.95 to 1.00. Moderate agreement was observed for absolute length of hemorrhage and edema (0.54 to 0.60) with good reproducibility (0.78 to 0.83). Agreement for the Brain and Spinal Injury Center score showed the lowest interrater agreement with an overall kappa of 0.27 (0.20, 0.34). For 7 of the 8 variables related to spinal cord injury, agreement improved between the first and second evaluation. Continuous diameter measures of the spinal cord and spinal canal using interclass correlation coefficient varied substantially (0.23 to 0.83).CONCLUSIONS:Agreement was more consistent for the ordinal measures of spinal cord injury than continuous measures. Good to excellent agreement on length and location of spinal cord hemorrhage and edema can be achieved with ordinal measures alone.

In 2006, the National Institute of Neurological Disorders and Stroke (NINDS) began a process to develop common data elements (CDEs) to provide a standardized method for the collection of clinical data related to neurologic diseases.1-3 Recognizing that there is a lack of clear and consistent terminology for spine disorders, particularly spinal cord injury (SCI), in 2014, the NINDS convened a workgroup comprising expert stakeholders for the development of SCI CDE instruments that included clinical care assessments and imaging.3-8 This new set of SCI CDE instruments aimed to increase the efficiency and value of clinical research studies and treatment, increase data quality, facilitate data sharing, and help educate new clinical investigators.3 Investigators are expected to incorporate the CDE modules in grant applications and National Institutes of Health–funded research.The MR imaging SCI CDE subset was created to be a comprehensive and standardized terminology for describing MR imaging findings in patients with SCI. This collection consists of a case report form (CRF) containing 35 discrete measures and responses divided into 4 main categories: general imaging characteristics, spinal injury features, canal and cord measurements, and chronic SCI features. The responses are of 3 types: Boolean, categoric, and an ordinal range representing specific anatomic locations. These measures were chosen to represent both objective and subjective assessment derived from routine clinical MR images. The workgroup codified these features using existing CDEs that have proved value in the published literature, and when ones did not exist, the workgroup developed the feature and the response parameters.As with the development of any CRF used for a clinical trial or research, the goal is to provide an instrument that provides useful data representations that are reproducible across trained observers and institutions, require minimal cognitive effort, minimize ambiguity, and are both accurate and precise. Reproducibility of the observations through rigorous testing by multiple observers is a needed step to validate the instrument before clinical or research use. However, the evaluation process may not entirely reproduce the clinical environment in which it is meant to be used such that datasets and observers are overly prepared or optimized. Therefore, the goal of this study is to determine the inter- and intrarater reliability of the NINDS MR imaging CDEs when assessed by MR imaging experts with familiarity with SCI. We hypothesize that there will be good to excellent agreement (kappa >0.4) among the expert raters after limited training.  相似文献   
70.
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