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41.
Primitive Neuroectodermal Tumors of the Central Nervous System 总被引:2,自引:0,他引:2
Lucy Balian Rorke M.D. John Q. Trojanowski M.D. Ph.D. Virginia MY Lee Ph.D. Robert A. Zimmerman M.D. Leslie N. Sutton M.D. Jaclyn A. Biegel Ph.D. Joel W. Goldwein M.D. Roger J. Packer M.D. 《Brain pathology (Zurich, Switzerland)》1997,7(2):765-784
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
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
42.
Morphometric diagnosis of serous effusions: refinement of differences between benign and malignant cases by use of outlying values and larger sample size. 下载免费PDF全文
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
43.
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45.
C1-esterase inhibitor blocks T lymphocyte proliferation and cytotoxic T lymphocyte generation in vitro 总被引:1,自引:0,他引:1
We have previously shown that activated C1s complement and activated T
cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation
of desLys58 beta2m. This process can specifically be inhibited by
C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously
added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed
lymphocyte culture (MLC) increased the endogenous production of IL-2 and
the generation of allo-specific cytotoxic T lymphocytes. C1-inh was
purified from fresh human plasma and added to human or murine MLC and
mitogen-stimulated lymphocyte cultures grown in the presence of
complement-inactivated serum. Read-outs were cell proliferation, lymphokine
production and development of T cell-mediated cytotoxicity. We found that
addition of C1-inh to MLC and mitogen- exposed murine and human lymphocyte
cultures inhibited proliferation, the development of allospecific cytotoxic
activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12
and IFN-gamma. These data clearly demonstrate a regulatory function of
C1-inh on T cell- mediated immune functions.
相似文献
46.
Morse MA Garst J Osada T Khan S Hobeika A Clay TM Valente N Shreeniwas R Sutton MA Delcayre A Hsu DH Le Pecq JB Lyerly HK 《Journal of translational medicine》2005,3(1):9-8
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
47.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
48.
John D Kriesel Deanna A Sutton Susan Schulman Annette W Fothergill Michael G Rinaldi 《Medical mycology》2008,46(6):607-610
We report a case of a life-threatening, recurrent, and azole-resistant pulmonary coccidioidomycosis in a patient receiving long-term fluconazole therapy for a history of coccidioidal meningitis. Since this diagnosis, the patient has received weekly amphotericin B for more than four years and remains in remission with a stable serum Coccidioides complement fixation antibody titer. 相似文献
49.
Elizabeth K. McLean A. E. M. McLean P. M. Sutton 《International journal of experimental pathology》1969,50(5):502-506
An improved method for production of cirrhosis of the liver in rats is described. Rats are given CCl4 and phenobarbitone simultaneously. The method doubles the yield of cirrhotic animals and halves the time taken for their production, in comparison with CCl4 alone.CCl4 inhalation results in fewer intercurrent deaths than oral dosing of CCl4. The cirrhosis as observed histologically is accompanied by gross nodularity of the liver, splenomegaly, portal hypertension and testicular atrophy. About 50 per cent of animals have measurable ascites. Animals killed during application of the new method show that cirrhosis develops only after 4 weeks of CCl4 dosage. 相似文献
50.
Successful outcome with day 4 embryo transfer after preimplantation diagnosis for genetically transmitted diseases 总被引:4,自引:5,他引:4
Preimplantation genetic diagnosis was performed in 61 day 3 embryos
obtained by in-vitro fertilization from seven patient carriers of
haemophilia, Marfan's syndrome, Bloch-Sulzemberg syndrome (incontinentia
pigmentosa) or X chromosome-linked immune deficiency, retinitis pigmentosa,
and FG syndrome, which is characterized by mental retardation and
hypotonia. After multiplex polymerase chain reaction, 16 embryos were
diagnosed as being unaffected, and these were transferred to the uterus on
the following day (day 4). Of these embryos, six (37.5%) implanted,
resulting in the delivery of a singleton and a twin pregnancy, a late
second trimester miscarriage (twins at week 20) and a first trimester
miscarriage at week 8. All the diagnoses were confirmed by amniocentesis.
We report for the first time a late day 4 transfer of biopsied human
embryos undergoing preimplantation genetic diagnosis. This transfer
schedule allows an extra day to perform genetic analyses on single
blastomeres and to monitor any adverse effect of the biopsy procedure.
相似文献