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101.
Angela Pucci MD Ezio David MD Michele di Summa MD Enrico Donegani MD Valeria Ghisetti MD Mario Morea MD Franco Mollo MD 《Cardiovascular pathology》1993,2(4):259-261
Dissecting aneurysms of coronary arteries are a rare finding and have never been reported in a cardiac allograft. We found two spontaneous dissecting aneurysms on the middle third of both the left anterior descending and the right coronary arteries in a female cardiac transplantation recipient. She died 43 days after cardiac transplantation after developing human cytomegalovirus pneumonia and pancreatitis. Dissecting coronary aneurysms, microfoci of subendocardial coagulative necrosis, and area of subepicardial dystrophic calcifications were discovered at necropsy examination. 相似文献
102.
Craig Evinger Michele A. Basso Karen A. Manning Patrick A. Sibony John J. Pellegrini Anja K. E. Horn 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,92(3):507-515
Summary In humans and rats we found that nicotine transiently modifies the blink reflex. For blinks elicited by stimulation of the supraorbital branch of the trigeminal nerve, nicotine decreased the magnitude of the orbicularis oculi electromyogram (OOemg) and increased the latency of only the long-latency (R2) component. For blinks elicited by electrical stimulation of the cornea, nicotine decreased the magnitude and increased the latency of the single component of OOemg response. Since nicotine modified only one component of the supraorbitally elicited blink reflex, nicotine must act primarily on the central nervous system rather than at the muscle. The effects of nicotine could be caused by direct action on lower brainstem interneurons or indirectly by modulating descending systems impinging on blink interneurons. Since precollicular decerebration eliminated nicotine's effects on the blink reflex, nicotine must act through descending systems. Three lines of evidence suggest that nicotine affects the blink reflex through the basal ganglia by causing dopamine release in the striatum. First, stimulation of the substantia nigra mimicked the effects of nicotine on the blink reflex. Second, haloperidol, a dopamine (D2) receptor antagonist, blocked the effect of nicotine on the blink reflex. Third, apomorphine, a D2 receptor agonist, mimicked the effects of nicotine on the blink reflex. 相似文献
103.
The effects of the antioxidant alpha-lipoic acid (LA) on the proliferation of mitogen-stimulated human peripheral blood lymphocytes (HPBL) were investigated in comparison to its effects on the proliferation of two leukaemic T cell lines, Jurkat and CCRF-CEM. At low mM concentrations, LA inhibited in a dose-dependent manner DNA synthesis of HPBL stimulated with either phorbol myristate acetate (PMA) in combination with ionomycin (IoM), or phytohaemagglutinin (PHA). At similar concentrations, LA inhibited the proliferation of Jurkat and CCRF-CEM cells. However, LA was preferentially cytotoxic to the leukaemic cell lines. The selective toxicity of LA to Jurkat cells was shown by electron microscopy (EM) to be due to the induction of apoptosis. Furthermore, LA had different effects on the secretion of interleukin-2 (IL-2) and steady-state levels of IL-2 mRNA in mitogen-stimulated HPBL depending on the mitogens used. LA dramatically increased the induction of IL-2 mRNA and IL-2 protein secretion in PMA/IoM-stimulated HPBL, whereas it inhibited these in HPBL stimulated with PHA. The differential effects of LA on normal and leukaemic T lymphocytes may indicate a new route towards development of therapeutic agents. 相似文献
104.
Michele C. Hindi-Alexander Ph.D. Maria A. Zielezny Ph.D. Naris Montes R.N. M.S. Bonnie Bullough Ph.D. Elliott Middleton Jr. M.D. Dutzu H. Rosner M.D. William M. London Ed.M. 《The Journal of allergy and clinical immunology》1985,75(6):709-715
After literature reports linking fibrocystic breast disease (FBD) to methylxanthine ingestion, a pilot study was undertaken to investigate the possible contribution of theophylline to this effect. The major goal of this project was to measure the effect of theophylline therapy on FBD in asthmatic women. All women attending an allergy clinic or an obstetrics/gynecology clinic over a 9-month period were examined to clinically assess FBD and were asked to complete a detailed questionnaire covering health history, other risk factors, and drug and dietary methylxanthines. The sample included 62 asthmatic women, 66 allergic but not asthmatic women, and 72 nonallergic and nonasthmatic women. By use of the FBD clinical taxonomy with its 19-point scale going from 0 to 18 that was developed for this study, the three groups did not differ significantly in terms of mean severity of FBD. On analyzing the effect of each of the methylxanthines on FBD severity, there is clear evidence that total methylxanthines was a contributing factor in FBD severity with or without adjustment for relevant variables, such as age, menopause, pregnancies, and groups. Theophylline was significant only when adjustments were made for age, pregnancy, and menopause in contrast to caffeine that was only significant with no adjustments. 相似文献
105.
Terracciano LM Bernasconi B Ruck P Stallmach T Briner J Sauter G Moch H Vecchione R Pollice L Pettinato G Gürtl B Ratschek M De Krijger R Tornillo L Bruder E 《Human pathology》2003,34(9):864-871
Hepatoblastoma (HB) is the most common liver tumor in childhood and differs in its environmental risk factors and genetic background from hepatocellular carcinoma. HB is associated with inherited conditions such as familial adenomatous polyposis and Beckwith-Wiedemann syndrome, suggesting the importance of genetic abnormalities in the pathogenesis and progression of this disease. It has a very polymorphous morphology. A diverse range of cytogenetic alterations has been reported to date, the most frequent being trisomy 2 and trisomy 20. Thirty-five HB specimens from 31 patients (22 purely epithelial, 4 purely mesenchymal, 9 mixed) were examined by comparative genomic hybridization (CGH), a technique that enables us to screen the entire tumor genome for genetic losses and gains. Our aims were as follows: (1) to characterize chromosome abnormalities that appear in this tumor and (2) to identify possible differences between different histologic subtypes of HB. We found significant gains of genetic material, with very little difference in the number and type of alterations between the different histologic components of HB. The most frequent alterations were gains of Xp (15 cases, 43%) and Xq (21 cases, 60%). This finding was also confirmed by fluorescent in situ hybridization performed on nuclei extracted from 6 specimens. Other common alterations were 1p-, 2q+, 2q-, 4q-, and 4q+. We found no difference between different histologic subtypes, a finding that may be in agreement with the hypothesis of a common clonal origin for the different components. An hitherto-unreported high frequency of X chromosome gains may support the assumption that X-linked genes are involved in the development of this neoplasm. 相似文献
106.
Anti-MOG autoantibodies in Italian multiple sclerosis patients: specificity, sensitivity and clinical association 总被引:2,自引:0,他引:2
Mantegazza R Cristaldini P Bernasconi P Baggi F Pedotti R Piccini I Mascoli N La Mantia L Antozzi C Simoncini O Cornelio F Milanese C 《International immunology》2004,16(4):559-565
There is considerable evidence that multiple sclerosis (MS) is an immune-mediated disease characterized by infiltration of inflammatory cells into the CNS and demyelination. Several myelin proteins may be encephalitogenic, including myelin basic protein, proteolipid protein and myelin oligodendrocyte glycoprotein (MOG), the latter being expressed on the external layer of myelin sheaths and hence accessible to antibody attack. We investigated MOG autoreactivity in serum and cerebrospinal fluid (CSF) by ELISA, employing the recombinant extracellular domain of MOG as antigen. We tested serum samples from 262 MS patients (175 relapsing-remitting, 43 primary progressive and 44 secondary progressive), 131 patients with other neurological diseases (OND) and 307 healthy controls. No patients or controls were receiving immunomodulating treatments. We found anti-MOG antibodies in the serum of 13.7% MS patients, mainly in those with secondary progressive MS (25%), in 13.7% of OND patients and in 6.2% of controls. We found a direct correlation (R(2) = 0.6, P = 0.002) between disease severity and anti-MOG titer only in patients with primary and secondary progressive MS. Anti-MOG antibodies were present in the CSF of 11.4% MS patients and 18.9% OND patients. Intrathecal synthesis of anti-MOG antibodies was demonstrated in four (4.5%) of MS patients and no OND patients. Anti-MOG antibodies are not specific for MS; however, they may characterize a subset of MS patients and this may be revealed by serial assays in relation to changing disease phase. 相似文献
107.
108.
Michele Guida Addolorata Casamassima Giulia Monticelli Michele Quaranta Giuseppe Colucci 《Journal of translational medicine》2007,5(1):51
Background and purpose
Metastatic renal cell carcinoma (MRCC) has a poor prognosis with a median overall survival of about one year. Since only a minority of patients experienced therapeutic benefit to current treatments, several studies have attempted to identify factors that may have an impact on response and survival. Cytokines play a crucial role in the host's immune response by regulating the development and function of a lot of biological compartments. Nevertheless, available data on basal cytokine levels in MRCC are very few and no clear profile of serum cytokines has been identified yet in these patients population. Thus, determining the levels of cytokines in MRCC could not only help in understanding the biological mechanisms of the tumor growth, but also in evaluating if different cytokine profiles are correlated with particular clinical behaviors. 相似文献109.
Sonic hedgehog guides commissural axons along the longitudinal axis of the spinal cord 总被引:2,自引:0,他引:2
Bourikas D Pekarik V Baeriswyl T Grunditz A Sadhu R Nardó M Stoeckli ET 《Nature neuroscience》2005,8(3):297-304
Dorsal commissural axons in the developing spinal cord cross the floor plate, then turn rostrally and grow along the longitudinal axis, close to the floor plate. We used a subtractive hybridization approach to identify guidance cues responsible for the rostral turn in chicken embryos. One of the candidates was the morphogen Sonic hedgehog (Shh). Silencing of the gene SHH (which encodes Shh) by in ovo RNAi during commissural axon navigation demonstrated a repulsive role in post-commissural axon guidance. This effect of Shh was not mediated by Patched (Ptc) and Smoothened (Smo), the receptors that mediate effects of Shh in morphogenesis and commissural axon growth toward the floor plate. Rather, functional in vivo studies showed that the repulsive effect of Shh on postcommissural axons was mediated by Hedgehog interacting protein (Hip). 相似文献
110.
Mario Arpinati Gabriella Chirumbolo Benedetta Urbini Francesca Bonifazi Giuseppe Bandini Yogen Saunthararajah Alessandra Zagnoli Marta Stanzani Sadia Falcioni Giulia Perrone Sante Tura Michele Baccarani Damiano Rondelli 《Biology of blood and marrow transplantation》2004,10(2):106-115
Human dendritic cells (DC) comprise 2 subsets-plasmacytoid CD123(+) and myeloid CD11c(+) DC-that may have distinct roles in the regulation of immunity after allogeneic hematopoietic stem cell transplantation. In this study, we analyzed the kinetics of CD123(+) DC and CD11c(+) DC reconstitution in 31 patients who underwent transplantation with allogeneic granulocyte colony-stimulating factor-mobilized peripheral blood (PB) stem cells from HLA-identical sibling donors after myeloablative conditioning. Lineage marker-negative HLA-DR(+) CD11c(+) CD11c(+) DC and lineage marker-negative HLA-DR(+) CD123(+) CD123(+) DC, as well as monocytes and lymphoid subsets, were enumerated in donor grafts and in the PB of patients at various time points after transplantation. Reconstitution of both CD11c(+) DC and CD123(+) DC to normal levels occurred within 6 to 12 months and was not affected by the diagnosis, preparatory regimen, or graft composition. However, PB CD11c(+) DC and CD123(+) DC counts were significantly reduced in patients with acute GVHD grade II to IV (at 1 and 3 months) and grade I (at 1 month). Patients with chronic GVHD instead showed reduced CD123(+) DC counts only 6 months after transplantation. Moreover, treatment with steroids (>0.1 mg/kg) was significantly associated with reduced PB CD11c(+) DC and CD123(+) DC counts at all time points after transplantation. In multivariate analysis, only acute GVHD affected DC reconstitution early after transplantation. These results will prompt new studies addressing whether DC reconstitution correlates with immunity against infectious agents or with graft-versus-tumor reactions after PB stem cell allotransplantation. 相似文献