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31.
We studied bone mass and metabolism in 30 adult women (age 28.5 +/- 1.3) with thalassemia major (TM) and evaluated whether prolonged hormone replacement therapy (HRT) was able to optimize bone accrual. TM patients had reduced bone mass, increased bone turnover and lower serum gonadotropin and estradiol levels compared with 10 normal women of similar age. A significant correlation was found between bone mass and sex hormone levels. Six TM patients with normal ovarian function had normal bone turnover markers and modestly low bone mass (lumbar spine -1.29 +/- 0.31; femoral neck -0.60+/-0.21; Z-score). The other 24 TM women were hypogonadic and had significantly lower bone mass for age (lumbar spine -2.35 +/- 0.2, femoral neck -1.83 +/- 0.2) and increased bone turnover relative to eugonadal women. Of the hypogonadal patients, 13 had taken HRT since age 15 +/- 1 years, but their bone mass and turnover markers were not different than untreated hypogonadal patients. In conclusion, while hypogonadism negatively affects bone mass acquisition in adult TM women, HRT at the standard replacement doses is not sufficient to secure optimal bone accrual.  相似文献   
32.
Dorcas Hager Padget was a pioneer in the fields of neurosurgical illustration and neuroembryology who practiced during the early 20th century at The Johns Hopkins University. Without a college degree, she trained as a medical illustrator in the Johns Hopkins School of Medicine's Department of Art as Applied to Medicine under Max Br?del. She began her career working for Walter Dandy as his medical artist, gaining worldwide recognition for her neurosurgical illustrations. With Dandy's encouragement, Hager Padget undertook her own scientific research, studying neurodevelopment and aneurysm formation in the circle of Willis by using human embryos from the world-renowned Carnegie Collection. She made lasting contributions to the field of neuroembryology, publishing the first major work on neurodevelopment of the cerebral arterial and venous systems. Following Dandy's death in 1946, Hager Padget began a full-time career as a scientific researcher, first at the Department of Embryology at the Carnegie Institution of Washington in Baltimore and later at the University of Maryland School of Medicine. She continued to make contributions to the field of congenital malformations of the brain and spine, coining the term "neuroschisis" to describe a possible mechanism of neural tube damage leading to the creation of a myelomeningocele. The authors describe Dorcas Hager Padget's contributions to neurosurgical illustration and neuroembryology, as well as her remarkable career.  相似文献   
33.
This longitudinal study examined the relation between life stress and basic beliefs about self-worth and the benevolence and meaningfulness of the world among mothers of children undergoing bone marrow transplantation (BMT). One hundred mothers completed study measures during the child's hospitalization for BMT and 1 year later. Prior trauma and recent negative events were associated with basic beliefs during hospitalization and also with changes in basic beliefs in the subsequent year, with distress mediating some of these relations. Findings also demonstrated relations between basic beliefs and physical and mental functioning. However, each basic belief exhibited different relations with study variables, suggesting the need to investigate them separately.  相似文献   
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35.
The literature on immunosenescence has focused mainly on T cell impairment. However, it is well known that B function is also profoundly affected. In particular, several studies have shown age-related changes in immunoglobulin serum levels. Concerning allergic diseases, the incidence of onset of allergic symptoms, as well as their severity, seems to decrease with age. So, the decline of onset of allergic symptoms observed in ageing might result from a decrease of serum total IgE due to an unbalance of cytokines and soluble factors involved in its production. To gain insight into the mechanisms of age related incidence of onset of allergic symptoms, as well as their severity, in this study we have evaluated in a sample of young (12 females and 15 males, range 20-64 years) and old (42 females and 20, males range 70-93 years) individuals serum values of IgE and sCD23 and in vitro Type 2 cytokine production. Total serum IgE levels were quantified by CAP-system fluorescence enzyme immunoassay. Serum CD23 levels were measured by a sandwich enzyme-linked immunoassay. Enzyme immunoassay tests have been used to quantify IL-4, IL-10 and IL-13 on mitogen-stimulated cultures. Serum total IgE and sCD23 in the two groups of young and old subjects were not significantly different. No detectable levels of IL-4, IL-10 and IL-13 were observed in supernatants from unstimulated cultures in all the subjects tested. After 48 h stimulation with PHA, cytokine amounts became detectable in all subjects. However, the values of the cytokines under study were not significantly different between young and old subjects. In our study, we have not been able to show no impairment in the afferent (type 2 cytokine production) and in the central (serum IgE and sCD23 levels) branch of allergic responses. Previous studies have shown that the efferent branch, at least studied as basophil releasability and bronchial responsiveness, is not impaired in elderly. In conclusion, as suggested from the present and previous papers it is questionable whether there is sufficient information to validate the statement that the incidence of allergic diseases decreases with age.  相似文献   
36.
At a fundamental level, protein adsorption to a synthetic surface must be strongly influenced by the interaction between the peptide residues presented by the protein's surface (primary protein structure) and the functional groups presented by the synthetic surface. In this study, semi-empirical molecular modeling was used along with experimental wetting data to theoretically approach protein adsorption at this primary structural level. Changes in enthalpy, entropy, and Gibbs free energy were calculated as a function of residue-surface separation distance for the adsorption of individual hydrophobic peptide residues (valine, leucine, phenylalanine) on alkanethiol self-assembled monolayers on gold [Au-S(CH(2))(15)-X; X = CH(3), OH, NH(3)(+), COO(-)]. The results predict that the adsorption of each type of hydrophobic residue is energetically favorable and entropy dominated on a methyl-terminated hydrophobic surface, energetically unfavorable and enthalpy dominated on a hydroxyl-terminated neutral hydrophilic surface, and very slightly favorable to unfavorable and enthalpy dominated on charged surfaces. These theoretical results provide a basis for understanding some of the fundamental effects governing protein adsorption to synthetic surfaces. This level of understanding is needed for the proactive design of surfaces to control protein adsorption and subsequent cellular response for both implant and tissue engineering applications.  相似文献   
37.
Members of the heat shock protein 70 (HSP70) family display a broad cellular localization and thus bind a repertoire of chaperoned peptides potentially derived from proteins of different cellular compartments. In this report, we show that HSP70 purified from human melanoma can activate T cells recognizing melanoma differentiation antigens in an antigen- and HLA class I-dependent fashion. HLA class I-restricted anti-melanoma T cells were susceptible to MHC-restricted, HSP70-dependent stimulation, indicating that HSP70 complexed peptides were able to gain access to the class I HLA presentation pathway. In addition, MHC matching between the melanoma cells used as a source of HSP and the responding T cells were not required, indicating that HSP70 activation may occur across MHC barriers. Besides the MHC-restricted and peptide-dependent activation pathway, HSP70 with no endogenous complexed peptides or HSP70 purified from antigen-negative cells was also able to induce IFN-gamma release by antimelanoma T cells by a MHC-independent mechanism. In this case, however, higher doses of HSP70 were required. The capacity to activate class I-restricted, antitumor T cells as well as antigen-presenting cells, together with the finding that the HSP70 chaperoned peptide repertoire includes melanoma-shared epitopes, holds promise for a HSP70-based cancer vaccine.  相似文献   
38.
Consideration of the number of prostate biopsy samples found to be positive for cancer may add clinically useful information to T stage, Gleason score, and prostate-specific antigen level in predicting outcome after radical prostatectomy. Higher radiation doses and neoadjuvant hormone therapy has been applied successfully to patients with higher risk disease. Brachytherapy has emerged as a modality for localized prostate cancer with outcomes and toxicity being further defined. Efforts to measure and improve quality of life are an important part of prostate cancer research. Standard management of metastatic disease remains androgen ablation, with long-term side effects being recognized. Newer hormonal and chemotherapeutic agents are being explored for patients with metastatic disease.  相似文献   
39.
Few cases of anti-colon cancer specific T lymphocytes have been described so far. Moreover, the majority of these effectors were generated in vitro by stimulating PBMC from patients or healthy donors with peptides that were derived from proteins expressed and/or secreted by colon cancer tissue such as CEA, Mucin or Her-2/neu. The aim of our study was to evaluate the immunogenicity of colorectal carcinomas in an autologous setting. We exploited the antigen processing and presentation capacity of dendritic cells (DC) to establish an in vitro autologous system that can bypass the need of obtaining cultured tumor cells. DC were generated from the adherent monocyte fraction of PBMC taken from stage II/III colorectal cancer patients. A single cell suspension was prepared by mechanical and enzymatic disruption of the surgical specimens immediately after resection. DC were loaded with autologous tumor lysate, obtained by repeated freezing and thawing, before being used as stimulators for autologous PBL. HLA-class II restricted T cells that recognize the autologous tumor could be generated in a proportion of patients. The fine specificity of the anti-tumor T cells indicates that differentiation as well as tumor restricted antigens are expressed in colon cancer and that these antigens can evoke a class II HLA-restricted response in an autologous setting. Altogether these findings may open a new perspective for a DC based vaccination of colon cancer patients.  相似文献   
40.
PURPOSE: To determine the clinical response rate of the combination of weekly intravenous (IV) gemcitabine with continuous infusion fluorouracil (5-FU) in patients with metastatic renal cell carcinoma (RCC). PATIENTS AND METHODS: Between June 1998 and February 1999, 41 patients with metastatic RCC were enrolled onto this multi-institutional phase II study of gemcitabine 600 mg/m(2) over 30 minutes on days 1, 8, and 15 and 5-FU 150 mg/m(2)/d via continuous IV infusion through a permanent catheter on days 1 to 21 of a 28-day cycle. Patients had a Cancer and Leukemia Group B performance status of 0 or 1, with a median time since diagnosis of metastatic disease of 10 months (range, 0 to 129 months). Thirty-three patients (80%) had multiple metastatic sites, and 34 patients (83%) had prior chemotherapy or immunotherapy. RESULTS: Of the 39 assessable patients, there were no complete responses but seven partial responses (objective response rate = 17%; 95% confidence interval, 8% to 34%). Five minor responses (25% to 50% decreased tumor size) were also observed. The duration of response for the seven partial responders was 2, 3, 7, 8, 10, 11, and 14 months. Median progression-free survival for the gemcitabine/5-FU group was 28.7 weeks versus 8 weeks for a similar cohort of patients treated on previous phase II studies at the University of Chicago (P =.008). The regimen was well tolerated, with fatigue, mucositis, nausea/vomiting, and grade 2 hematologic toxicities being most common. CONCLUSION: Weekly gemcitabine with continuous infusion 5-FU is an active combination in patients with metastatic RCC. Therapy was well tolerated and produced an improvement in progression-free survival over historical controls.  相似文献   
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