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1.
While there is a burgeoning body of research linking smoking during pregnancy to problem behaviour in offspring, a major criticism of this work has been the crude measurement of exposure in these studies (e.g. retrospective, self-reported only) that could lead to biased estimates. To address this issue, we used a pregnancy cohort with repeated prospective measures of exposure as well as biological assays to generate estimates of exposure patterns using a range of modelling techniques. In this paper we report on the analytical approaches we have developed, including patterns of exposure over time and best-estimate approaches that combine self-report and cotinine measures, and compare their predictive value in relation to different dimensions of fetal growth as a first step towards examining the utility of greater precision of exposure measurement.
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies.  相似文献   
2.
This project was supported by two separate research grants from the Trust Fund Board, Washington Association for Retarded Citizens to Richard Neel and Truman E. Coggins. The research was also supported by a training grant to the University of Washington entitled Comprehensive Training in Mental Retardation and Other Handicapping Conditions (MCH-000913, Clifford J. Sells, M.D., Principal investigator); and, a training grant to the University of Arizona entitled Doctoral and Post-Doctoral Leadership Training and Clinical Research, Teaching and Administration: Clinical Language Research Center (G008630088, Linda Swisher, Ph.D., principal investigator). We are indeed grateful to the parents of our five subjects for their patience, understanding, and commitment. Finally, we express our appreciation to Arelene Chaussee for her technical expertise and untiring spirit.  相似文献   
3.
Paraneoplastic neurologic syndromes are disorders of the nervous system function caused by cancer but not due to metastatic disease, vascular or metabolic deficits, infections, nutritive deficiency, nor side effects of antineoplastic drugs or irradiation. Immunologic factors probably play the crucial role in the pathogenesis of paraneoplastic neurologic syndromes, but nonimmunologic mechanisms that include metabolic abnormalities and competition for substrate are also involved. Paraneoplastic cerebellar degeneration most commonly occurs in the setting of gynecologic cancers, but it accompanies the small-cell lung cancer too. Other tumors are infrequently associated with cerebellar degeneration. Several paraneoplastic antibodies have been identified in patients with paraneoplastic cerebellar degeneration. Their association with particular cancers may help identify an occult lesion. Anti-Yo antibodies are directed against Purkinje cell antigens and occur in patients with cerebellar degeneration who have breast cancer or gynecologic tumors. A target antigen of anti-Yo antibody is CDR2 protein that is normally expressed only in the brain and testis. Patients with paraneoplastic cerebellar degeneration present with dizziness, nausea and vomiting followed by gait instability, diplopia, gait and appendicular ataxia, dysarthria and dysphagia. Therapeutic options include tumor excision, chemotherapy and/or irradiation, and adjuvant therapy with glucocorticoids, immunoglobulins and plasmapheresis. The role of plasmapheresis in the treatment of paraneoplastic cerebellar degeneration is still uncertain. Reports of its efficacy are anecdotal. We present patient with paraneoplastic cerebellar degeneration with positive anti-Yo antibodies and tumor of the ovaries whose neurologic status significantly improved after four daily plasmaphereses, which was accompanied by a fourfold decrease in the anti-Yo antibodies titer. Further investigations are needed to define a protocol for plasmapheresis in the treatment of patients with paraneoplastic syndromes.  相似文献   
4.
A 71-year-old woman presented with malaise, skin bruising, epistaxis, and gingival bleeding of recent and prompt onset. There was no adenopathy. The liver and spleen were not enlarged. Bone marrow aspirate showed a polymorphous infiltration with lymphocytes (22%), typical Marschalko plasma cells (16%), plasmacytoid lymphocytes (29%), lymphoblasts (8%), and immunoblasts (13%). The immunoblasts morphologically resembled lymphosarcoma cells with a frequent "clover-leaf" appearance. An IgM paraprotein concentration in serum was 38.5 g/L. The bone marrow histopathology confirmed the presence of heterogenous cell infiltration, with 30% of the population being comprised of lymphoblasts and immunoblasts. In order to differentiate a polymorphous variant of Waldenstr?m macroglobulinemia (WM) from the more common small cell lymphocytic lymphoma (SLL) in anaplastic metamorphosis, flow cytometric studies were performed on marrow specimens. A typically bright surface IgM (lambda) was demonstrated with a less bright CD38. Further immunophenotype was HLA-DR+, CD19+, CD20+ and CD10-, CD22-, T-Ag- and kappa light chain- expression. This corroborated the diagnosis of an extremely rare, polymorphous variant of WM. The marrow cytogenetics disclosed 50% (10/20) pathologic metaphases 48,X,dup(X)(p21p22),der(2), +5,del(6)(q11q21), +12,inv(16)(p13q22), del(17) (p12), and 50% normal metaphases. The patient was treated with a LOPP protocol. She failed to respond and died 5 months after the diagnosis with myocardial and renal insufficiency complicating a pronounced pancytopenia in the peripheral blood.  相似文献   
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7.
The relationship between the extent of bone marrow reticulin and collagen fibrosis and the concentration of granulocytic (CFU-GM), erythroid (BFU-E) and megakaryocyte (CFU-Mk) progenitor cells in the peripheral blood of patients with primary agnogenic myeloid metaplasia (AMM) and secondary myelofibrosis (sMF) has not been definitively correlated. We studied 23 patients with established diagnosis of AMM and 12 patients with sMF for the extent of reticulin and collagen bone marrow fibrosis and for the spontaneous colony (sCFU-GM, sBFU-E and sCFU-Mk) formation. The control group consisted of 11 healthy volunteers. Trephine biopsy of the posterior iliac crest was performed in all individuals studied to determine the type and degree of reticulin and collagen fibrosis. Gomori's silver impregnation technique was used. sCFU-GM, sBFU-E and sCFU-Mk colony formation was related positively to spleen size, the white blood cell counts and the degree of collagen fibrosis in AMM (p < 0.01). Stimulated CFU-GM were also significantly correlated with the degree of bone marrow reticulin and collagen fibrosis. There was no correlation between the extent of peripheral blood progenitor concentration and the degree of bone marrow reticulin or collagen fibrosis in sMF and in control individuals. In conclusion, the extent of bone marrow fibrosis is significantly correlated with the peripheral blood progenitor colony formation in AMM but not in sMF.  相似文献   
8.

Background

Oral squamous cell carcinoma (OSCC) constitutes 3 percent of all cancers with predominant occurrence in middle aged and elderly males. Tumour recurrence worsens disease prognosis and decreases quality of life in patients with OSCC. Proinflammatory cytokines such as interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) have been suggested to play a certain role in variety of tumours. The aim of this study was to investigate the relationship of pretreatment serum IL-6 and TNF-α levels on tumour recurrence in patients with OSCC in order to identify potential biomarkers for the early detection of disease recurrence.

Material and Methods

The patients with newly diagnosed OSCC were treated and followed from the first visit from November 2006 until January 2008. Serum IL-6 and TNF-α concentrations were measured. The records of the patients were re-examined in July 2012 and data were recorded about cancer characteristics and tumour recurrence. Disease free survival was analyzed by Kaplan-Meier survival curves, log rank test and Cox proportional hazards regression.

Results

Serum IL-6 was shown as an independent risk factor for tumour recurrence.

Conclusions

Pretreatment serum IL-6 concentration may be a useful biomarker for identification of OSCC patients with increased risk of the disease recurrence. Key words: Serum IL-6, serum TNF-α, oral cancer, recurrence.  相似文献   
9.
Mice lacking the large zinc finger protein Schnurri-3 (Shn3) display increased bone mass, in part, attributable to augmented osteoblastic bone formation. Here, we show that in addition to regulating bone formation, Shn3 indirectly controls bone resorption by osteoclasts in vivo. Although Shn3 plays no cell-intrinsic role in osteoclasts, Shn3-deficient animals show decreased serum markers of bone turnover. Mesenchymal cells lacking Shn3 are defective in promoting osteoclastogenesis in response to selective stimuli, likely attributable to reduced expression of the key osteoclastogenic factor receptor activator of nuclear factor-κB ligand. The bone phenotype of Shn3-deficient mice becomes more pronounced with age, and mice lacking Shn3 are completely resistant to disuse osteopenia, a process that requires functional osteoclasts. Finally, selective deletion of Shn3 in the mesenchymal lineage recapitulates the high bone mass phenotype of global Shn3 KO mice, including reduced osteoclastic bone catabolism in vivo, indicating that Shn3 expression in mesenchymal cells directly controls osteoblastic bone formation and indirectly regulates osteoclastic bone resorption.  相似文献   
10.
We evaluated the influence of allelic frequency of the human leukocyte antigen (HLA) -DRB1 on the acquisition of antibody response against malaria sporozoite and merozoite peptides in patients with Plasmodium vivax malaria acquired in endemic areas of Brazil. IgG antibodies were detected by enzyme-linked immunosorbent assay against four peptides of circumsporozoite protein (CSP) (amino, carboxyl, and VK210 and VK247 repeats) and peptides of merozoite surface protein 1 (MSP-1), apical membrane antigen 1 (AMA-1), and Duffy-binding protein (DBP). We found an association between HLA-DR3 and HLA-DR5 alleles and lack of antibody response to CSP amino terminal, as well as an association between HLA-DR3 and the highest antibody response to MSP1 (Pv200L). In conclusion, we suggest a potential regulatory role of the HLA-DRB1 alleles in the production of antibodies to a conserved region of P. vivax CSP and MSP1 in Brazilian population exposed to malaria.  相似文献   
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