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21.
María Francisca Garijo José Fernando Val‐Bernal Alfonso Vega Daniel Val 《Pathology international》2008,58(12):787-791
Despite the frequent use of fine‐needle aspiration, core biopsy and surgery, postoperative spindle cell nodule (PSCN) is a rare pathological complication that may be diagnostically treacherous. Presented herein is the case of a 52‐year‐old woman who developed a 7 mm mammary nodular lesion 66 days after removal of an area of columnar cell hyperplasia involving cellular and architectural atypia, performed with the Mammotome Breast Biopsy System. The lesion was highly cellular and composed of intersecting fascicles of plump spindle cells with blunt‐ended elongated nuclei and nucleoli easily visible. Interspersed mononuclear cells and hemosiderin‐laden macrophages were evident. PSCN is a reactive, benign myofibroblastic proliferation. Differential diagnosis includes benign and malignant spindle cell lesions of the breast. Recognition of this reactive lesion will avoid overdiagnosis of spindle cell malignant tumor. Attention to clinicopathological and histological features should result in accurate recognition of this lesion. 相似文献
22.
Specific allergens enhance elastase release in stimulated neutrophils from asthmatic patients 总被引:12,自引:0,他引:12
Monteseirín J Bonilla I Camacho MJ Chacón P Vega A Chaparro A Conde J Sobrino F 《International archives of allergy and immunology》2003,131(3):174-181
BACKGROUND: The presence of the three forms of IgE receptor - the heterotrimeric high-affinity receptor for IgE (Fc(epsilon)RI), the low-affinity receptor for IgE (Fc(epsilon)RII/CD23) and the Mac-2/IgE-binding protein (epsilonBP) - has been demonstrated on human neutrophils. We have previously shown that specific allergens are able to activate functional responses by neutrophils from allergic patients sensitized to those allergens. Neutrophils are present at the sites of allergic inflammation. The primary (azurophilic) granules of neutrophils contain a variety of enzymes, such as elastase, that might potentiate inflammation. It is not known whether specific allergens are able to elicit elastase release by neutrophils from allergic patients. In addition, we attempted to evaluate the relationship between neutrophil degranulation and lung function of the patients, measured as FEV(1). METHODS: Neutrophils were challenged in vitro with the specific allergens that produced clinical symptoms in asthmatic patients. The cells were also challenged with allergen to which the patients were not sensitive. Neutrophils from normal subjects were challenged with allergens as control. RESULTS: The in vitro challenge of neutrophils with allergens to which the patients were sensitive elicited a release of elastase by these cells. The in vitro activation of neutrophils was highly allergen specific; allergens other than those accounting for clinical symptoms did not evoke elastase release, and allergens were ineffective on neutrophils from healthy donors. A significant inverse correlation was observed between elastase release and patients' lung function, measured as FEV(1). CONCLUSION: An IgE-dependent mechanism might promote elastase release by neutrophils at allergic sites. There is a significant inverse relationship between levels of elastase released by neutrophils from allergic patients and lung function, as assessed by FEV(1). 相似文献
23.
Brunetti-Pierri N Andreucci MV Tuzzi R Vega GR Gray G McKeown C Ballabio A Andria G Meroni G Parenti G 《American journal of medical genetics. Part A》2003,(2):164-168
Partial trisomy of the long arm of chromosome 10 is a well-defined but rare syndrome. Clinical features of this chromosomopathy are a distinctive dysmorphic appearance, developmental delay, growth retardation, and in some cases, abnormalities of the extremities and renal, cardiac and ocular anomalies. This report describes a neonate with symmetric growth retardation and multiple dysmorphic features, in whom chromosomal analysis revealed a partial trisomy of chromosome 10q with a monosomy of the 13q34 region. The phenotype shares many common features with previously published cases. In addition to the typical features, our case also shows renal hypoplasia with early renal insufficiency and some genital anomalies. 相似文献
24.
This study was designed to determine the effects of opiate drugs on the electrical activity of afferent neurons and on the ionic currents of hair cells from semicircular canals. Experiments were done on larval axolotls (Ambystoma tigrinum). The multiunit spike activity of afferent neurons was recorded in the isolated inner ear under both resting conditions and mechanical stimulation. Ionic currents were recorded using voltage clamp of hair cells isolated from the semicircular canal. In the isolated inner-ear preparation, microperfusion of either non-specific opioid receptor antagonist naloxone (10 nM to 1 mM), mu receptor agonist [D-Ala(2), N-Me-Phe(4),Gly(5)-ol]-enkephalin (1 pM to 10 microM), or kappa receptor antagonist nor-binaltorphimine (10 nM to 100 microM) elicited a dose-dependent long-lasting (>5 min) increase of the electrical discharge of afferent neurons. The mu receptor agonist funaltrexamine (1 nM to 100 microM) and the kappa receptor agonist U-50488 (1 nM to 10 microM) diminished the basal spike discharge of vestibular afferents. The delta receptor agonist D-Pen(2)-D-Pen(5)-enkephalin (1 nM to 10 mM) and the antagonist naltrindole (1 nM to 10 mM) were without a significant effect. The only drug that displayed a significant action on hair-cell ionic currents was trans-(+/-)-3,4-dichloro-N-methyl-N-(2-[1-pyrrolidinyl]-cyclohexyl) benzeneacetamide methanesulfonate (U-50488) that reduced the Ca(2+) current in a dose-dependent fashion. On its own, mu receptor agonist [D-Ala(2), N-Me-Phe(4),Gly(5)-ol]-enkephalin (0.01 and 10 microM) significantly potentiated the response of afferent neurons to the excitatory amino acid agonist (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (0.1 microM), while synaptic transmission was blocked by the use of high-Mg(2+), low-Ca(2+) solutions. Our data indicate that the activity of vestibular afferent neurons may be regulated in a complex fashion by opioid receptors: mu opioid receptors mediating an excitatory, postsynaptic modulatory input to afferent neurons, and kappa receptors mediating an inhibitory, presynaptic input to hair cells. 相似文献
25.
Monteseirín J Bonilla I Chacón P Vega A Camacho MJ Guardia P Conde J Sobrino F 《Allergy》2003,58(10):1027-1032
BACKGROUND: CD14 is a most important monocyte surface molecule. Recently, it has been reported that there is an important relationship between CD14 and immunoglobulin E, and that regulation of CD14 expression is an effector mechanism mediating apoptosis of monocytes. OBJECTIVE: The present study was designed to determine whether specific allergens were able to modulate CD14 expression and apoptosis by monocytes from allergic patients or whether specific immunotherapy (IT) might affect these processes. METHODS: One group of adult allergic asthmatic patients had received IT for the previous 3 years. Another similar group was not treated with IT. We challenged peripheral blood monocytes from both groups of asthmatic patients in vitro with the specific allergen that produced clinical symptoms in asthmatic patients. The cells were also challenged with allergen to which the patients were not sensitive. Monocytes from normal subjects were also challenged with allergens. Expression of CD14 on the monocyte surface was analyzed by flow cytometry, and soluble CD14 (sCD14) in culture supernatant by enzyme-linked immunosorbent assay. The three groups of subjects were challenged with allergens, and apoptosis was analyzed by flow cytometry. RESULTS: When monocytes from non-IT-treated asthmatic patients were cultivated with the allergens to which the patients were sensitive, a significant up-regulation on the monocyte surface was observed compared with results from the healthy group (P < 0.003) and from the IT asthmatic group (P < 0.003). A significantly higher sCD14 level was observed in the culture supernatant of the monocytes from the IT asthmatic group were observed compared with those from the healthy group (P < 0.001) and those from the non-IT asthmatic group (P < 0.001). A significantly higher apoptosis level was observed in monocytes from the IT asthmatic group compared with those from the healthy group (P < 0.001) and those from the non-IT asthmatic group (<0.001). CONCLUSIONS: We present evidence that the expression of CD14 on the surface of monocytes and the apoptosis of the same cells can be modulated by an allergen-dependent mechanism. These processes can be affected by IT. 相似文献
26.
Leone PE Vega ME Jervis P Pestaña A Alonso J Paz-y-Miño C 《Journal of human genetics》2003,48(12):639-641
RB1 is the gene responsible for retinoblastoma, the most common malignant intraocular tumor of infancy and early childhood. There are no reports about this gene in Ecuadorian populations, and only a few studies have been published in Latin America about this subject. There is a spectrum of more than 370 mutations described in the RB1 gene mutation database (http://www.d-lohmann.de/Rb/mutations.html), and alterations have been found in 25 of the 27 exons. During the exon-by-exon analysis of 31 tumor and blood samples from Ecuadorian patients, we found two new mutations and three novel polymorphisms. One of the polymorphisms is located in intron 26 where no alterations of the gene have been described previously. The polymorphisms were found in all of the patients tumor samples, but not in normal population, suggesting there might be a relationship between these polymorphisms and the development of retinoblastoma in the Ecuadorian population.The nucleotide sequence data reported are available in the GenBank database under the accession numbers: AY243567, AY260472, AY260473, AY273783 相似文献
27.
Free cells were obtained by sequential incubations of pig gastric mucosa with pronase and collagenase. Approximately 10-15% of the cell population represented parietal cells. Accumulation of aminopyrine (AP) in the acid compartments of parietal cells was used as an index of their acid production. Histamine, carbachol and pentagastrin each independently stimulated aminopyrine accumulation. The initial rate of aminopyrine accumulation, observed after addition of 10(-4) M carbachol or 10(-6) M pentagastrin, were 32% and 10%, respectively, of that observed with 10(-4) M histamine. Steady-state aminopyrine accumulation in the presence of 10(-4) M histamine, 10(-4) M carbachol or 10(-6) M pentagastrin were 6.2 +/- 3.3, 2.6 +/- 0.6 and 3.0 +/- 1.5 pmol AP per 10(4) parietal cells, respectively (mean +/- SD, n = 5). The EC50 value for histamine was 3.4 +/- 1.4 X 10(-7) M, and for pentagastrin 5.9 +/- 4.2 X 10(-8) M (mean +/- SD, n = 5). The dose-response curve for carbachol was biphasic. A plateau was reached at 10(-5)-10(-4) M carbachol, and for this phase an apparent EC50 of 2.1 +/- 1.4 X 10(-6) M carbachol was calculated (mean +/- SD, n = 5). A further increase to 10(-3) M carbachol increased the aminopyrine accumulation. Atropine (10(-6) M) inhibited the response to concentrations up to 10(-4) M carbachol, but was without effect on the histamine- and pentagastrin-stimulation. The H2-receptor antagonist, cimetidine, right-shifted the dose--response curve for histamine. Also, the pentagastrin-stimulated aminopyrine accumulation was inhibited by cimetidine.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
28.
Evaluation of Urea-motility-indole medium for recognition and differentiation of Salmonella and Shigella species in stool cultures. 下载免费PDF全文
M Rosa Fraile D Vega Aleman C Fernandez Gutierrez 《Journal of clinical microbiology》1980,12(3):310-313
A semisolid urea-motility-indole medium designed for detection in Enterobacteriaceae of urease activity, motility, and indole production in one tube was prepared and evaluated. The formulation of the medium was similar to that of Christensen urea agar, but the agar concentration was 0.2%, and 1% tryptone was added. Results with 687 strains of Enterobacteriaceae were the same as those obtained with standard test media (98% overall agreement). The urea-motility-indole medium was also used in combination with Kligler iron agar for the recognition and differentiation of Salmonella and Shigella species from colonies picked from plating media in fecal cultures. This combination was compared with the combination of Kligler iron agar and lysine iron agar with 507 strains of non-lactose-fermenting Enterobacteriaceae. Although both combinations enabled the presumptive recognition and differentiation of Salmonella and Shigella species, an analysis of data indicated that the combination of Kligler iron agar and urea-motility-indole medium performed better than the combination of Kligler iron agar and lysine iron agar in detecting Salmonella and Shigella species. 相似文献
29.
J. A. Vega I. Esteban F. J. Naves M. E. Valle L. Malinovsky 《Anatomy and embryology》1995,191(1):33-39
We used immunohistochemical techniques and monoclonal antibodies to localize two basement membrane components (laminin and type IV collagen) in the nerves and sensory nerve formations, or corpuscles, supplying human digital skin. Furthermore, neurofilament proteins, S-100 protein and epithelial membrane antigen were studied in parallel. In dermal nerve trunks, immunostaining for laminin and type IV collagen was found to be co-localized in the perineurium and the Schwann cells, the stronger immunoreactivity being at the external surface of the cells. In the Meissner digital corpuscles, the immunoreactivity for laminin and type IV collagen was mainly observed underlying the cell surface of lamellar cells, while the cytoplasm was weakly immunolabelled or unlabelled. Finally, within Pacinian corpuscles co-localization of the two basement membrane molecules was encountered in the inner core, intermediate layer, outer core and capsule. Laminin and type IV collagen immunoreactivities were also found in blood vessels and sweat glands, apparently labelling basement membrane structures. The present results provide evidence for the presence of basement membrane in all periaxonic cells forming human cutaneous sensory nerve formations, and suggest that all of them are able to synthesize and release some basement membrane components, such as laminin and type IV collagen. The possible role of laminin in sensory nerve formations is discussed. 相似文献
30.
Eighty-seven culturable endophytic bacterial isolates in 19 genera were obtained from coffee plants collected in Colombia (n = 67), Hawaii (n = 17), and Mexico (n = 3). Both Gram positive and Gram negative bacteria were isolated, with a greater percentage (68%) being Gram negative. Tissues yielding bacterial endophytes included adult plant leaves, various parts of the berry (e.g., crown, pulp, peduncle and seed), and leaves, stems, and roots of seedlings. Some of the bacteria also occurred as epiphytes. The highest number of bacteria among the berry tissues sampled was isolated from the seed, and includes Bacillus , Burkholderia , Clavibacter , Curtobacterium , Escherichia , Micrococcus , Pantoea , Pseudomonas , Serratia , and Stenotrophomonas . This is the first survey of the endophytic bacteria diversity in various coffee tissues, and the first study reporting endophytic bacteria in coffee seeds. The possible role for these bacteria in the biology of the coffee plant remains unknown. 相似文献