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101.
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
102.
103.
104.
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105.
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
106.
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
107.
Verga L Concardi M Pilotto A Bellini O Pasotti M Repetto A Tavazzi L Arbustini E 《Virchows Archiv : an international journal of pathology》2003,443(5):664-671
Mutations of the LMNA gene encoding the lamin A and C nuclear envelope proteins cause an autosomal dominant form of dilated cardiomyopathy (DCM) with atrioventricular block (AVB). The aim of this study was to investigate ultrastructural nuclear membrane changes by conventional electron microscopy and protein expression by immuno-electron microscopy in the heart of patients with DCM and AVB due to LMNA gene mutations. Four immunohistochemical techniques were used: pre-embedding and post-embedding in Epon-Araldite resin and London Resin White (LRW), with and without silver enhancement. Parallel light microscopy immunohistochemistry studies were performed. Conventional electron microscopy showed a loss of integrity of the myocyte nuclei with blebs of the nuclear membrane, herniations and delamination of the nuclear lamina and nuclear pore clustering. Post-embedding LRW was the most informative technique for morphology and immuno-labelling. Immuno-labelling was almost absent in the nuclear envelope of patients with LMNA gene mutations, but intensely present in controls. The loss of labelling selectively affected myocyte nuclei; the endothelial cell nuclei were immunostained in patients and controls. Light immunohistochemistry confirmed the results. These findings confirm the hypothesis that LMNA gene defects are associated with a loss of protein expression in the selective compartment of non-cycling myocyte nuclei. 相似文献
108.
Bertini M Ferrara M De Gennaro L Curcio G Fratello F Romei V Pauri F Rossini PM 《Journal of sleep research》2004,13(1):31-36
Transcranial magnetic stimulation (TMS) is a recently established technique in the neurosciences that allows the non-invasive assessment, among other parameters, of the excitability of motor cortex. Up to now, its application to sleep research has been very scarce and because of technical problems it provided contrasting results. In fact delivering one single suprathreshold magnetic stimulus easily awakes subjects, or lightens their sleep. For this reason, in the present study we assessed motor thresholds (MTs) upon rapid eye movement (REM) and non-rapid eye movement (NREM) sleep awakenings, both in the first and in the last part of the night. Taking into account that a full re-establishment of wake regional brain activity patterns upon awakening from sleep needs up to 20-30 min, it is possible to make inferences about the neurophysiological characteristics of the different sleep stages by analyzing the variables of interest immediately after provoked awakenings. Ten female volunteers slept in the lab for four consecutive nights. During the first night the MTs were collected, following a standardized procedure: 5 min before lights off, upon stage 2 awakening (second NREM period), upon REM sleep awakening (second REM period), upon the final morning awakening (always from stage 2). Results showed that MTs increased linearly from presleep wakefulness to REM sleep awakenings, and from the latter to stage 2 awakenings. There was also a time-of-night effect on MTs upon awakening from stage 2, indicating that MTs decreased from the first to the second part of the night. The increase in corticospinal excitability across the night, which parallels the fulfillment of sleep need, is consistent with the linear decrease of auditory arousal thresholds during the night. The maximal reduction of corticospinal excitability during early NREM sleep can be related to the hyperpolarization of thalamocortical neurons, and is in line with the decreased metabolic activity of motor cortices during this sleep stage. On the contrary, the increase of MTs upon REM sleep awakenings should reflect peripheral factors. We conclude that our findings legitimate the introduction of the TMS technique as a new proper tool in sleep research. 相似文献
109.
Bardaro T Falco G Sparago A Mercadante V Gean Molins E Tarantino E Ursini MV D'Urso M 《Human mutation》2003,21(1):8-11
Familial incontinentia pigmenti (IP) is a rare X-linked dominant disorder that affects ectodermal tissues. Over 90% of IP carrier females have a recurrent genomic deletion of exons 4-10 of the NEMO (IKBKG-IKKgamma) gene, which encodes a regulatory component of the IkB kinase complex, required to activate the NF-kB pathway. In IP, mutations in NEMOlead to the complete loss of NF-kB activation creating a susceptibility to cellular apoptosis in response to TNF-alpha. This condition is lethal for males during embryogenesis while females, who are mosaic as a result of X-inactivation, can survive. Recently, a second nonfunctional copy of the gene, DeltaNEMO, was identified, opposite in direction to NEMO in a 35.5-kb duplicated sequence tract. PCR-based detection of the NEMO deletion is diagnostic for IP disease. However, we present instances in which ex 4-10 DeltaNEMO pseudogene deletion occurs in unaffected parents of two females with clinically characteristic IP. These were missed by the currently standard PCR-based method, but can be easily discriminated by a new PCR-based test reported here that permits unambiguous molecular diagnosis and proper familial genetic counseling for IP. 相似文献
110.
Cloning and characterization of two catechol 1,2-dioxygenase genes from Acinetobacter radioresistens S13 总被引:2,自引:0,他引:2
Caposio P Pessione E Giuffrida G Conti A Landolfo S Giunta C Gribaudo G 《Research in microbiology》2002,153(2):69-74
Two novel catechol 1,2-dioxygenase (C 1,2-O) genes have been isolated from an Acinetobacter radioresistens strain that grows on phenol or benzoate as sole carbon and energy source. Designated as catA(A) and catA(B), they encode proteins composed of 314 and 306 amino acids, whose deduced sequences indicate that they have approximately 53% identity, whereas their NH2-terminal and COOH-terminal regions have no sequences in common. This may explain their different thermal and pH stability. Polyclonal antibodies raised against an amino-terminal CatA(A) peptide or the whole CatA(B) protein were used to establish their inducible and differential expression patterns upon bacterial growth in phenol or benzoate. The CatA(A) protein (IsoA) was induced by both phenol and benzoate though with different kinetics, whereas the catA(B) product (IsoB) was constitutively produced at low levels that increased only during growth in the presence of benzoate. 相似文献