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111.
Martins LM Peltre G da Costa Faro CJ Pires EM da Cruz Inácio FF 《International archives of allergy and immunology》2005,136(1):7-15
BACKGROUND: Ingestion of snails can induce strong asthmatic or anaphylactic responses, mainly in house-dust-mite-sensitized patients. The aim of this study was to identify the Helix aspersa (Hel a), Theba pisana (The p) and Otala lactea (Ota l) allergens and the extent of their cross-reactivity with the Dermatophagoides pteronyssinus (Der p) mite. PATIENTS AND METHODS: In 60 atopic patients, skin prick tests (SPT) to snail and D. pteronyssinus, total and specific IgE, specific IgE immunoblots, RAST and immunoblot inhibition assays were performed. RESULTS: Mean total IgE was >1,000 kU/l. Mean specific IgE (class 6 for Der p and class 2 for Hel a) SPT were positive in 44 patients for snail and in 56 for mite. Isoelectric focusing (IEF) and SDS-PAGE followed by immunoblotting of H. aspersa extract enabled the identification of 27 and 20 allergens, respectively. Myosin heavy chains from snails (molecular weight >208 kDa) disclosed two major allergens. Hel a and Der p RAST were strongly inhibited by their homologous extracts, with Hel a RAST being inhibited by the Der p extract to a much greater extent (72.6%) than the inverse (5.6%). A complete inhibition of the immunoblots by their homologous extract was obtained. However, Hel a extract did not inhibit Der p IEF separated recognition. On the other hand, mite extract extensively inhibited snail immunoblots from both IEF and SDS-PAGE separations. Immune detection on chicken, pig, rabbit, cow and horse myosins did not reveal any IgE cross recognition with snail. CONCLUSIONS: In most cases of snail allergy, mite appeared to be the sensitizing agent. Nevertheless, snails may also be able to induce sensitization by themselves. This hypothesis is supported by the finding of specific IgE to Hel a in 2 patients who did not show specific IgE to Der p, and one of them was suffering from asthma after snail ingestion. 相似文献
112.
Adrenocortical adenoma and carcinoma: histopathological and molecular comparative analysis. 总被引:8,自引:0,他引:8
Alexander Stojadinovic Murray F Brennan Axel Hoos Atilla Omeroglu Denis H Y Leung Maria E Dudas Aviram Nissan Carlos Cordon-Cardo Ronald A Ghossein 《Modern pathology》2003,16(8):742-751
We compared histomorphological features and molecular expression profiles of adrenocortical adenomas (ACAd) and carcinomas (ACCa). A critical histopathological review (mean, 11 slides per patient) was conducted of 37 ACAd and 67 ACCa. Paraffin-embedded tissue cores of ACAd (n = 33) and ACCa (n = 38) were arrayed in triplicate on tissue microarrays. Expression profiles of p53, mdm-2, p21, Bcl-2, cyclin D1, p27, and Ki-67 were investigated by immunohistochemistry and correlated with histopathology and patient outcome using standard statistical methodology. Median follow-up period was 5 years. Tumor necrosis, atypical mitoses, and >1 mitosis per 50 high-power fields were factors that were highly specific for ACCa (P <.001). Number (0 to 4) of unfavorable markers [Ki-67 (+), p21 (+), p27 (+), mdm-2(-)] expressed was significantly associated with mitotic activity and morphologic index (i.e., number of adverse morphologic features) and highly predictive of malignancy (P <.001). Ki-67 overexpression occurred in 0 ACAd and 36% ACCa (P <.001) and was significantly associated with mitotic rate and unfavorable morphologic index (P <.001). Tumor necrosis, atypical mitoses, >5 mitoses per 50 high-power fields, sinusoidal invasion, histologic index of >5, and presence of more than two unfavorable molecular markers were associated significantly with metastasis in ACCa. Well-established histopathologic criteria and Ki-67 can specifically distinguish ACCAd from ACCa. Tumor cell proliferation (Ki-67) correlates with mitotic activity and morphologic index. Tumor morphology is a better predictor of metastatic risk in ACCa than current immunohistochemistry-detected cell cycle regulatory and proliferation-associated proteins. 相似文献
113.
Rubem Carlos Araujo Guedes Romualdo José do Carmo 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,39(3):341-349
Summary The ionic composition of the internal environment was altered in rabbits by means of gastric washing, combined with intramuscular administration of 3-Beta-aminoethylpyrazole. The effects of this treatment on cortical spreading depression (SD) were studied. C1- and Na+ concentrations decreased significantly in serum and in cerebrospinal fluid after the treatment. This made the animals much more susceptible to SD, as established by the high incidence of spontaneous SD, increased SD velocity of propagation and facilitated its interhemispheric transfer. An intensification of the epileptiform activity associated with SD was also observed. Intravenous replacement of NaCl abolished the above effects on SD. When the intravenous replacement was done with Na-Isethionate, those effects were enhanced. It is concluded that chloride deficiency was the main factor responsible for the observed facilitating effects.This work was supported by grants from the BNDE (FUNTEC-74 e 143), CNPq and CAPES 相似文献
114.
Suriano G Oliveira MJ Huntsman D Mateus AR Ferreira P Casares F Oliveira C Carneiro F Machado JC Mareel M Seruca R 《Human molecular genetics》2003,12(22):3007-3016
In Hereditary Diffuse Gastric Cancer syndrome, E-cadherin germline mutations of the missense type harbour significant functional consequences. In this study, we have characterised the effect of T340A, A617T, A634V and V832M E-cadherin germline missense mutations on cell morphology, motility and proliferation. Wild-type E-cadherin and A617T expressing cells have an epithelial-like morphology, with polarised cells migrating unidirectionally. T340A and A634V expressing cells, fibroblast-like, have a high motile phenotype. We show that this phenotype is dependent on an increased level of active RhoA. V832M expressing cells grow in piled-up structure of round cells, as an effect of the disturbance of the binding between alpha-catenin and beta-catenin. The destabilisation of the adhesion complex is shown to hamper the motile capabilities of these cells. We did not observe any effect of the E-cadherin mutations on cell proliferation. We show the existence of a genotype-phenotype correlation between different E-cadherin mutations and cell behaviour. However, we demonstrate that the ability of cells expressing the different E-cadherin mutations to invade is independent on their motile capabilities, providing evidence that motility is neither necessary nor sufficient for cells to invade. Our data give new insights into the understanding of the mechanisms linking invasion and E-cadherin mutations in diffuse gastric cancer. 相似文献
115.
Carlos Guillen-Astete Iria Miguens-Blanco Miguel Zamorano-Serrano Elena Machin-Muñoz Paloma Gallego-Rodríguez Cristina de-la-Casa-Resino 《Educación Médica》2019
Introduction
The care activity of internal resident doctors is common to practically all medical and surgical training programs; however, there are no national data available regarding the situation of this activity from the perspective of the resident. The present study has sought to collect the opinion of the resident internal physicians on the health care performance and the teaching character that links them to their corresponding emergency departments, in the following areas: overall training value, appreciation of the workload, characteristics of the morning rotation, supervision or tutoring, etc.Method
The study was performed using a questionnaire that was distributed at the national level through the network of representatives of the SEMES-MIR group of the Spanish Society of Emergency and Emergency Medicine.Results
A total of 1083 questionnaires were collected from 38 hospitals, corresponding to a response rate of 28%. The most significant educational contribution was the general knowledge about emergency medical care and the interpretation of complementary tests, while the less significant were aspects related to pharmacoeconomics, sustainability and cost-benefit of medical and non-medical processes related to medicine Emergency. As for the burden of care during a day of continuous care, the first year residents saw a mean of 12.3 patients) (SD 2.2), the second and third year 18.1 (SD 2.2), and the older residents 14.5 (SD 2.4). Less than half (44%) of the respondents identified their supervision model as «direct», while 37.2% identified it as «semi-pyramidal». A minority (14.2%) of respondents acknowledged having been encouraged to undertake scientific activities related to emergency medicine.Conclusions
The results of this questionnaire should serve as a basis for the future planning of new models of teaching and care for residents and emergency services, as well as to stratify the priorities of attention to the relationship between emergency services and resident physicians. 相似文献116.
Dina Ruano António Macedo Maria Jo?o Soares José Valente Maria Helena Azevedo Carlos Pato Mara Helena Hutz Clarissa S Gama Maria Inês Lobato Paulo Belmonte-de-Abreu Peter Heutink Joana Almeida Palha 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(5):642-646
Several observations point to the involvement of disturbed lipid biology in schizophrenia. Reduced response to niacin flushing test, which involves vasodilatation induced by prostaglandin D2 (PGD2), is among the evidences, together with decreased CSF levels of lipocalin-type prostaglandin D2 synthase (PTGDS), the enzyme responsible for the synthesis of PGD2 in the brain. Since PTGDS is also a carrier for lipophilic molecules such as retinoids and thyroid hormones, altered PTGDS levels might influence both PGD2-mediated signaling, and vitamin A and thyroid hormone availability. To test whether genetic variants of PTGDS are involved in the etiology of schizophrenia, we searched for variants in the coding and regulatory regions of the gene. We identified four previously described polymorphisms. Using two case-control samples from Portugal and Brazil, none of the polymorphisms tested was associated with the disease. In addition, no transmission distortion was observed in an independent parents-offspring sample from the Azorean Islands. Our data do not support the involvement of the PTGDS gene in the etiology of schizophrenia. 相似文献
117.
Özcan Özdamar Rafael E. Delgado Syed Rahman Carlos Lopez 《Annals of biomedical engineering》1998,26(5):883-891
An innovative acoustic noise canceling method using adaptive Wiener filtering (AWF) was developed for improved acquisition of distortion product otoacoustic emissions (DPOAEs). The system used one microphone placed in the test ear for the primary signal. Noise reference signals were obtained from three different sources: (a) pre-stimulus response from the test ear microphone, (b) post-stimulus response from a microphone placed near the head of the subject and (c) post-stimulus response obtained from a microphone placed in the subjects nontest ear. In order to improve spectral estimation, block averaging of a different number of single sweep responses was used. DPOAE data were obtained from 11 ears of healthy newborns in a well-baby nursery of a hospital under typical noise conditions. Simultaneously obtained recordings from all three microphones were digitized, stored and processed off-line to evaluate the effects of AWF with respect to DPOAE detection and signal-to-noise ratio (SNR) improvement. Results show that compared to standard DPOAE processing, AWF improved signal detection and improved SNR. © 1998 Biomedical Engineering Society.
PAC98: 4364Jb, 4360-c, 8790+y 相似文献
118.
Summary The patterns of expression of the human-tumor-associated antigens, CO17-1A, GA73-3, BR55-2, GICA19-9, CA50 and carcino-embryonic antigen (CEA) were studied in the normal colonic mucosa (the last three also in the serum) of Sprague-Dawley rats. Four immunohistochemically different segments were identified: caecum, ascending colon, transverse colon and descending colon. The immunohistochemical reactions of the cells at the lower part of the crypt were essential for the distinction of the four segments. In the caecum, the MAbs 17-1A, 73-3 and 19-9 stained the glycocalyx of the cells of the lower part of the crypts and the Golgi apparatus of the intercalated cells (IC). MAb55-2 stained very weakly the goblet-like cells (GLC) of the lower part of the crypt of transverse colon, in addition to a nearly complete lack of reaction in the upper part of the crypts. In the ascending colon, the lower part of the crypts showed a characteristic diffuse staining of the intercalated cells with MAb55-2. The perinuclear and mucosal staining observed in the GLC of the transverse colon with MAbs 17-1A, 73-3 and 19-9 as against the supranuclear and Golgi zone staining observed in the GLC/goblet cells (GC)/columnar cells (CC) of the lower part of crypts of the descending colon with the same MAbs, distinguished the former segment from the latter. The IC demonstrated by immunohistochemistry in the lower parts of the crypts of caecum and ascending colon appear to correspond to the replicating cells of the colonic crypts. 相似文献
119.
Ignacio Prieto Charles Tease Nieves Pezzi José M. Buesa Sagrario Ortega Leonor Kremer Alicia Martínez Carlos Martínez-A Maj A. Hultén José L. Barbero 《Chromosome research》2004,12(3):197-213
Cohesins are chromosomal proteins that form complexes involved in the maintenance of sister chromatid cohesion during division of somatic and germ cells. Three meiosis-specific cohesin subunits have been reported in mammals, REC8, STAG3 and SMC1 beta; their expression in mouse spermatocytes has also been described. Here we studied the localization of different meiotic and mitotic cohesin components during prophase I in human and murine female germ cells. In normal and atretic human fetal oocytes, from leptotene to diplotene stages, REC8 and STAG3 colocalize in fibers. In murine oocytes, SMC1beta, SMC3 and STAG3 are localized along fibers that correspond first to the chromosome axis and then to the synaptonemal complex in pachytene. Mitotic cohesin subunit RAD21 is also found in fibers that decorate the SC during prophase I in mouse oocytes, suggesting a role for this cohesin in mammalian sister chromatid cohesion in female meiosis. We observed that, unlike human oocytes, murine synaptonemal complex protein SYCP3 localizes to nucleoli throughout prophase I stages, and centromeres cluster in discrete locations from leptotene to dictyate. At difference from meiosis in male mice, the cohesin axis is progressively lost during the first week after birth in females with a parallel destruction of the axial elements at dictyate arrest, demonstrating sexual dimorphism in sister chromatid cohesion in meiosis. 相似文献
120.
Ectodermal dysplasia with acanthosis nigricans (Lelis syndrome) 总被引:2,自引:0,他引:2
A 31-year-old male patient with ectodermal dysplasia and acanthosis nigricans is described. Clinical findings included hypotrichosis, hypohidrosis, palmoplantar hyperkeratosis, nail dystrophy, early onset loss of permanent dentition, mental retardation, and acanthosis nigricans. The findings suggest the diagnosis of Lelis syndrome, as described on the basis of seven unrelated cases. A review concerning this condition is also presented. 相似文献