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21.
An increased prevalence of bronchial hyper-responsiveness (BHR) has been demonstrated in children from a general population, and in non-asthmatic adults with allergic rhinitis. Thus, also children with allergic rhinitis are expected to be at higher risk of BHR. We evaluated the prevalence of BHR in a sample of non-asthmatic children with allergic rhinitis by means of the methacholine (Mch) bronchial challenge, and by monitorizing the airway patency using the daily peak expiratory flow variability (PEFv). Fifty-one children (ranged 6–15 years of age) with allergic rhinitis, ascertained by skin prick test to inhalant allergens, underwent a 14-day peak expiratory flow monitoring, and a Mch bronchial provocation challenge. Thirty healthy children matched for age, and sex served as control group. Thirty-one children in the rhinitis group (61%), and six (20%) in the control group were Mch+ (Mch provocative dose causing a 20% fall of forced expiratory volume in 1 s respect to baseline <2250  μ g, equivalent to 11.50  μ mol). In rhinitic children the PEFv did not significantly differ between Mch+ and Mch− subjects, but the total serum immunoglobulin E (IgE) were higher among Mch+. The persistent form of rhinitis was significantly associated to Mch positivity. Non-asthmatic children with allergic rhinitis displayed a high prevalence of BHR. The BHR was significantly associated with persistent rhinitis and with higher total IgE levels. Nevertheless, the spontaneous changes in airway patency, as expressed by PEFv, were within normal limits both in Mch+ and Mch− children.  相似文献   
22.
We report the results of a retrospective review of the outpatient pretransplantation workup for United Network for Organ Sharing (UNOS) 3 patients adopted at a liver transplantation (LT) center and illustrate the efficiency indicators used for quality evaluation and cost-analysis. A single-center, pre-LT evaluation workup was performed on an outpatient basis at a cost per patient evaluation of 2,770 Euros (). Objective measures were: the number of patients admitted to and excluded from each phase of the algorithm; the rate of patients admitted to pre-LT evaluation out of the total of referred patients (the referral efficiency rate); the rate of waitlisted patients out of those admitted to pre-LT evaluation (the evaluation efficiency rate); the rate of waitlisted patients out of those referred for LT (the process efficiency rate); and the cost per waitlisted patient, as the ratio of the cost per patient evaluation to the evaluation efficiency rate. From January 1, 1996, to October 1, 2004, 1,837 patients were referred for LT on an outpatient basis. Based on preemptive evaluation of the available clinical data, 412 patients (22.4%) were excluded from pre-LT evaluation and 1,425 (77.6%) were admitted to preliminary consultation. Among these, 603 (42.3%) were excluded from and 822 (57.7%) were admitted to pre-LT evaluation with a referral efficiency rate of 44.7% (822 of 1,837). Out of the patients evaluated for LT, 484 were waitlisted with a cost-utility and evaluation efficiency rate of 58.8% each (484 of 822). Of the 1,837 patients originally addressed for LT 484 were waitlisted, yielding a process efficiency rate of 26.3% (484 of 1,837) and a cost per waitlisted patient of 4,710.8. In conclusion, the 3 indicators allowed monitoring of the efficiency of the pre-LT evaluation algorithm. The current process efficiency rate at our center is low (26.3%), but avoiding early referrals we might increase it to 31.6%, with a 12% net saving on costs per waitlisted patient (from 4,710.8 to 4,165.4).  相似文献   
23.
An influence on drug-taking behaviours of the stress-related hypothalamo-pituitary-adrenal (HPA) axis and its final hormonal mediator, corticosterone, has previously been demonstrated. A role for cortically projecting cholinergic neurons in these behaviours can also be proposed. The experiments presented here examine the effect of the drug of abuse cocaine (15 mg/kg) on the release of acetylcholine (ACh) in the cortex of freely moving rats, using the technique of in vivo microdialysis. To assess a possible modulatory influence of the HPA axis via its final hormonal mediator corticosterone, the cocaine-induced effect on cortical ACh release in intact rats was compared to that in adrenalectomized (ADX) rats, which thus lacked their endogenous source of corticosterone, and in ADX rats in which the cocaine-induced corticosterone peak and/or the basal circadian concentrations of serum corticosterone were simulated by replacement treatments. The results reported here demonstrate that cortical ACh release is greatly increased by cocaine in intact rats; ADX prolongs the return to basal levels of cortical ACh, and the chronic replacement of circadian levels of corticosterone normalizes this effect. In contrast, during the plateau period of cocaine-induced increased cortical ACh release, where no effect of ADX is evident, rats with chronic replacement of corticosterone show an attenuated cocaine-induced cortical ACh release, and the acute replacement of the cocaine-induced corticosterone secretion further attenuates this response. These results demonstrate that cocaine stimulates cortically projecting cholinergic neurons, and that the HPA hormone corticosterone modulates this interaction in a complex manner which merits further investigation.  相似文献   
24.
Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease (JD), a chronic gastroenteritis of ruminants and other animals, including primates. Many evidences suggested association of MAP to Crohn's disease, a chronic granulomatous gastrointestinal disease of humans with strong similarities with JD. The present study attempts to evaluate global gene regulation in MAP, which has not been addressed previously, despite the availability of MAP genome sequence. For this purpose, we investigated: (i) the presence of sigma factors and their relationship to sigma factors of other mycobacteria (M. avium subsp.avium, M. tuberculosis, M. bovis, M. leprae and M. smegmatis), and (ii) their expression during different growth conditions and in vitro infection of intestinal epithelial Caco2 cells. MAP genome contains 19 putative sigma factor, but only 12 belong to gene families common to other mycobacteria. Gene expression was evaluated with Real-Time PCR during growth in 7H9 medium and mycobactin J, in 7H9 medium plus mycobactin J and lisozyme, and during infection of Caco2 cells: very different expression patterns were observed and, on the whole, only 7 sigma factors were found to be expressed. sigJ was upregulated during the infection of Caco2 cells. Even if only few sigma factors were expressed in the three conditions tested, the overall high numbers of MAP sigma factors suggests a noteworthy flexibility of this pathogen. Thus, this first report on expression of MAP sigma factors opens the way to an extensive characterization of global gene regulation, as a key to understand strategies of survival and mechanisms of infections used by this organism.  相似文献   
25.
Vitiligo is a skin disorder characterized by depigmented macules secondary to melanocyte loss. An unusual facet is its relation to melanoma: cytotoxic T lymphocytes directed to melanocyte antigens are found in both conditions and imply a breakdown of tolerance, yet the resulting immune reaction is the opposite. The mechanisms at the basis of these opposite effects are not known. Here, we performed a direct comparison of whole melanocyte-specific T cell populations in the two diseases. We demonstrate that neither precursor frequencies of Melan-A/MART-1-specific T lymphocytes nor their status of activation differ significantly. However, by using a tetramer-based T cell receptor down-regulation assay, we documented a higher affinity of vitiligo T cells. We calculated that the peptide concentration required for 50% of maximal receptor down-regulation differed by 6.5-fold between the two diseases. Moreover, only vitiligo T cells were capable of efficient receptor down-regulation and IFN-gamma production in response to HLA-matched melanoma cells, suggesting that this difference in receptor affinity is physiologically relevant. The differences in receptor affinity and tumor reactivity were confirmed by analyzing Melan-A/MART-1-specific clones established from the two diseases. Our results suggest that the quality, and not the quantity, of the melanocyte-specific cytotoxic responses differs between the two pathologies.  相似文献   
26.
Histological criteria for the diagnosis of reflux esophagitis include basal zone hyperplasia, stromal papillae elongation, and inflammatory infiltrate. However, endoscopic esophageal biopsy specimens may include little or no lamina propria. Intraepithelial T lymphocytes, seen in hematoxylin and eosin-stained sections as cells with irregular nuclear contours (CINC), may have a higher density in children with esophagitis. We evaluated the diagnostic accuracy of a numerical score built up by grading the "classical" parameters and its correlation with CINC density in grasp biopsy specimens obtained from children undergoing esophagogastroduodenoscopy with and without esophagitis. We analyzed esophageal biopsy specimens from 349 children (median age, 5 years) subdivided in 4 groups according to the previous routine histology report: group 1, 144 children with esophagitis; group 2, 65 controls; group 3, 51 children with dubious esophagitis; and group 4, 75 children with esophagitis on endoscopy but a normal histology report. A numerical value was assigned to each parameter; the sum of these values represented the histological score. We also evaluated intraepithelial CINC density (ie, number of CINC per high-power field). We separately analyzed histological sections with and without lamina propria. For both total score and for CINC density, we calculated a cutoff using a receiver operating characteristic curve. Cutoffs of 6 for score and of 4 for CINC density provided the best sensitivity and specificity. Sensitivity of the histological score was better in biopsy specimens containing lamina propria (94%) than in those without lamina propria (4%). Sensitivity of CINC density was satisfactory in both specimens with (78%) and without (75%) lamina propria. Specificity was satisfactory for both parameters. In conclusion, when lamina propria was present in sections of endoscopic esophageal biopsy specimens, histological score provided a better diagnostic accuracy for the diagnosis of esophagitis. However, when no lamina propria was present, as was the case in 67% of our children, CINC density had better sensitivity. In addition, this latter parameter showed esophageal mucosa damage in 34% of previously dubious cases or cases with esophagitis at endoscopy but a previous routine histology report of normal mucosa.  相似文献   
27.
The malignant phenotype of prostatic tumor cells correlates with the expression of both uPA and itscell-membrane receptor (uPAR); however, there is little information concerning the role of cell-bound uPAin matrix degradation and invasion. Our results suggest that cell-associated uPA plays a key role in regulat-ingthe amount of plasmin present at the surface of prostatic carcinoma (PRCA) cells and show that differ-entialproduction of uPA corresponds with the capacity to bind and activate plasminogen. In addition, weprovide direct evidence that both uPA secretion and the presence of uPA-uPAR complexes characterize theinvasive phenotype of PRCA cells and suggest the existence of several pathways by which tumor cells acquireplasmin activity. LNCaP cells (which do not produce uPA but express uPAR) may activate plasmin throughexogenous uPA. In vivo, the source of uPA may be infiltrating macrophages and/or fibroblasts as observedin several other systems. PAI-1 accumulation in the conditioned medium (CM) limits plasmin action to thepericellular microenvironment. Our results indicate that MMP-9 and MMP-2 are also activated by plasmingenerated by cell-bound but not by soluble, extracellular uPA. Plasmin activation and triggering of the pro-teolyticcascade involved in Matrigel invasion is blocked by antibodies against uPA (especially by anti- A-chainof uPA which interacts with uPAR) and by PA inhibitors such as p-aminobenzamidine which mayregulate levels of cell-bound uPA. uPA may also regulate growth in PRCA cells. Indeed, antibodies againstuPA A-chain (and also p-aminobenzamidine treatment) interfere with the ATF domain and inhibit cell growthin uPA-producing PC3 and DU145 prostate cancer cell lines, whereas exogenous uPA (HMW-uPA with ATF)induces growth of LNCaP prostate tumor cell line. These data support the hypothesis that in prostatic can-cerpatients at risk of progression, uPA/plasmin blockade may be of therapeutic value by blocking both growthof the primary tumor and dissemination of metastatic cells. ©Kluwer Academic Publishers  相似文献   
28.
MECP2 duplication syndrome (MDS; OMIM 300260) is an X‐linked neurodevelopmental disorder caused by nonrecurrent duplications of the Xq28 region involving the gene methyl‐CpG‐binding protein 2 (MECP2; OMIM 300005). The core phenotype of affected individuals includes infantile hypotonia, severe intellectual disability, very poor‐to‐absent speech, progressive spasticity, seizures, and recurrent infections. The condition is 100% penetrant in males, with observed variability in phenotypic expression within and between families. Features of MDS in individuals of African descent are not well known. Here, we describe a male patient from Cameroon, with MDS caused by an inherited 610 kb microduplication of Xq28 encompassing the genes MECP2, IRAK1, L1CAM, and SLC6A8. This report supplements the public data on MDS and contributes by highlighting the phenotype of this condition in affected individuals of African descent.  相似文献   
29.
Pain in individuals with RASopathies is a neglected topic in literature. In this article, we assessed prevalence and profile of pain in a sample of 80 individuals affected by RASopathies. The study sample included individuals with Noonan syndrome (N = 42), Costello syndrome (N = 17), and cardio‐facio‐cutaneous syndrome (N = 21). A set of standardized questionnaires and scales were administered (VAS/numeric scale, r‐FLACC, Wang‐Baker scale, NPSI, BPI, NCCPC‐R) to detect and characterize acute and chronic pain and to study the influence of pain on quality of life (PEDs‐QL, SF‐36) and sleeping patterns (SDSC); revision of past medical history and multisystemic evaluation was provided. Available clinical data were correlated to the presence of pain. High prevalence of acute (44%) and chronic (61%) pain was documented in the examined sample. Due to age and intellectual disability, acute pain was localized in 18/35 individuals and chronic pain in 33/49. Muscle‐skeletal and abdominal pain was more frequently reported. The intensity of acute and chronic pain interfered with daily activities in 1/3 of the sample. Pain negatively impacted on QoL and sleeping patterns. This work documents that pain is highly prevalent in RASopathies. Future studies including subjective and objective measures of pain are required to discriminate a somatosensory abnormality from an abnormal elaboration of painful stimuli at a central level.  相似文献   
30.
The erbB2 gene is often found amplified and/or overexpressed in breast cancer in which it has clinical relevance as prognostic and predictive factor. It is involved in growth regulation and has a role in the initial phases of cell proliferation, while in vivo and in vitro studies have suggested an involvement also in cell invasion and metastases. It is not clear if these two roles are mutually exclusive and little is known about the mechanisms by which erbB2 may be involved in the control of these processes. Our previous data on patient series suggested that erbB2 might be regulated in different ways depending on the neoplastic status of the cells and that it might be involved in different regulatory pathways. To test this hypothesis we have measured the serum-dependent regulation of erbB2 as a function of the expression of the antimetastatic gene, nm23, in a panel of breast cancer cell lines. The experimental model consisted of three cell lines having different proliferative and invasive potentials: a non-metastatic estrogen receptor (ER) positive cell line, MCF-7; a highly metastatic ER negative cell line, MDA-MB435; and the MDA-MB435 cell line transfected with the nm23-H1 antimetastatic gene (clone H1-177) which has lost the ability to invade and metastasize. We first analysed the serum concentration dependence of invasion and proliferation after 3-4 days of serum deprivation confirming the proliferative and invasive potential of the three cell lines. Modulation of erbB2 expression by different concentrations of serum was then studied. ErbB2 expression in MCF-7 cells showed a complex pattern due to serum modulation, whereas, it was not longer regulated by serum in the MDA-MB435 cell line. In H1-177 cells the erbB2 response to serum was restored and it was very similar to that observed in MCF-7. These data showed a tight association between nm23 and the regulation of erbB2 expression by serum factors suggesting that the role of erbB2 in invasion might be dependent on nm23 expression.  相似文献   
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