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31.
Trichoderma longibrachiatum was recovered from stool surveillance cultures and a perirectal ulcer biopsy specimen from a 29-year-old male who had received an allogeneic bone marrow transplant for acute lymphoblastic leukemia. The amphotericin B (2.0 microgram/ml) and itraconazole (1.0 microgram/ml) MICs for the organism were elevated. Therapy with these agents was unsuccessful, and the patient died on day 58 posttransplantation. At autopsy, histologic sections from the lungs, liver, brain, and intestinal wall showed infiltration by branching septate hyphae. Cultures were positive for Trichoderma longibrachiatum. While Trichoderma species have been recognized to be pathogenic in profoundly immunosuppressed hosts with increasing frequency, this is the first report of probable acquisition through the gastrointestinal tract. Salient features regarding the identification of molds in the Trichoderma longibrachiatum species aggregate are presented.  相似文献   
32.
The development of both adenocarcinoma of the jejunum and in situ squamous carcinoma of the oesophagus in an adult coeliac patient is described. Good evidence that adenocarcinoma of jejunum occurs more frequently in patients with coeliac disease has recently become available though this association has been suggested for some time. While oesophageal carcinoma has long been associated with coeliac disease, in situ carcinoma of oesophagus has not been previously described in these circumstances. We feel that the risk of this complication, as calculated from published series, warrants a screening programme for oesophageal malignancy in adult coeliacs.  相似文献   
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We report the first documented case of brain abscess due to the dematiaceous fungus Microascus cinereus, an organism common in soil and stored grain. M. cinereus was isolated from brain abscess material from a bone marrow transplant recipient. The patient responded well to treatment by amphotericin B lipid complex, itraconazole, and a craniotomy but later died from secondary complications caused by graft-versus-host disease.  相似文献   
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A scheme for the synthesis and purification of conjugates, composed of the type 12F capsular polysaccharide of Streptococcus pneumoniae (Pn12F) and diphtheria toxoid, is described. The scheme is a modification of that described previously for the Vi capsular polysaccharide of Salmonella typhi, a linear homopolymer of N-acetylgalactoseaminouronic acid (S. C. Szu, A. L. Stone, J. D. Robbins, R. Schneerson, and J. B. Robbins, J. Exp. Med. 166:1510-1524, 1986). Pn12F is a branched-chain copolymer composed of a hexasaccharide repeating unit containing an aminouronic acid, N-acetylmannoseaminouronic acid (K. Leontein, B. Lindberg, and J. Lonngren, Can. J. Chem. 59:2081-2085, 1981). Sulfhydryl groups were introduced into Pn12F by forming an amide bond between cystamine and carboxyl groups of N-acetylmannoseaminouronic acid in the presence of a carbodiimide. The disulfide moiety of cystamine was reduced to form the cysteamine derivative of Pn12F which was, in turn, covalently bound to diphtheria toxoid by using the heterobifunctional linker N-succinimidyl-3-(2-pyridylthio)propionate. Unbound, high-molecular-weight Pn12F was removed from the conjugate by hydrophobic interaction chromatography through octyl Sepharose by using n-octyl-beta-D-glucopyranoside as the eluent. In young outbred mice, Pn12F did not elicit detectable serum antibodies. Pn12F-diphtheria toxoid, in contrast, elicited antibodies after two injections and had T-cell-dependent properties as evidenced by a response to priming and by its ability to elicit booster responses. This scheme seems applicable to the synthesis of conjugates with other capsular polysaccharides containing aminouronic acids. Clinical evaluation of Pn12F-diphtheria toxoid conjugates in healthy and in immunocompromised hosts is planned.  相似文献   
35.
Primitive Neuroectodermal Tumors of the Central Nervous System   总被引:2,自引:0,他引:2  
Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers.  相似文献   
36.
Fifty cytologically malignant, five suspicious, and 27 cytologically benign serous effusions were assessed morphometrically for differences in mean and outlying nuclear and cytoplasmic variables. Significant differences were found between benign and malignant specimens for all nuclear morphometric variables measured, the most significant being largest nuclear area and diameter. No significant differences were found for cytoplasmic size variables. Although measurement of outlying values in serous effusions enhanced the difference between benign and malignant cell populations, it was of insufficient sensitivity or specificity to be of clinical diagnostic use. Increasing the sample size improved test performance but would be tedious to perform manually.  相似文献   
37.
BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors.  相似文献   
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