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101.
Xavier AC Siqueira SA Costa LJ Mauad T Nascimento Saldiva PH 《Virchows Archiv : an international journal of pathology》2005,446(3):225-231
Autopsy findings of missed diagnoses that would probably have changed management or prognosis occur in up to 29% of cases in general hospitals. Such proportions may be higher in subsets of patients with complex diseases. We reviewed 2908 consecutive autopsies performed over a period of 29 months in a large-volume hospital, analyzing 118 autopsies of patients with hematological malignancies or severe aplastic anemia. A review of macroscopic reports as well as microscopic examination of tissue samples was performed. Medical records were reviewed for clinical diagnoses. Discordances between clinical and autopsy diagnoses were classified using Goldmans criteria. Additionally, we searched for clinical parameters correlated with occurrence of class-I discrepancy using a multivariate method. Median age was 46.5 years, and 25.4% had received a hematopoietic stem-cell transplant. Overall, 11.9% (6.6–19.1%) of patients died before conclusion of the hematological diagnosis and 33% (24.6–42.3%) died with no active hematological disease. We found class-I discrepancy in 31.3% (23.1–40.5 %) of cases. The most common among these diagnoses were hematological disease, pneumonia and gastrointestinal bleeding. In a univariate analysis, being elderly (P=0.04) was positively correlated with the finding of class-I discrepancies; while, having received previous specific hematological treatment (P=0.0005) or hematopoietic stem-cell transplants (P=0.013), or being admitted to a specialized hematology unit (P=0.0006) were negatively correlated to the occurrence of such discrepancies. Multivariate analysis showed that care in a specialized hematology unit (OR 0.34, 0.12–0.93) was independently associated with lower occurrence of discrepancies. We concluded that critical diagnoses are often missed in highly complex hematological patients especially in the absence of admission to specialized hematology units. 相似文献
102.
Utilization of indole compounds by Cryptococcus neoformans to produce a melanin-like pigment 总被引:3,自引:0,他引:3
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Several indoles served as substrates for the phenoloxidase of Cryptococcus neoformans and resulted in the production of a melanin-like pigment. In general, a higher percentage of C. neoformans var. neoformans (A and D serotypes) isolates could produce pigment from indoles than could those of var. gattii (B and C serotypes). Only compounds with a hydroxyl or an amino group on the phenyl ring produced pigment; methoxy, nitro, methyl, and fluorine substituents on the phenyl ring were inactive, as was a hydroxyl group at the 2 position on the indole ring. The phenoloxidase of C. neoformans thus appears to differ from that found in Mycobacterium leprae, which cannot use a hydroxyindole, desoxyfructo-5-hydroxytryptamine, as a substrate. In addition, C. neoformans differs from M. leprae in that desoxyfructo-5-hydroxytryptamine does not inhibit the uptake of dihydroxyphenylalanine into the cell. 相似文献
103.
Recombinant cysteine proteinase from Leishmania (Leishmania) chagasi implicated in human and dog T-cell responses
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da Costa Pinheiro PH de Souza Dias S Eulálio KD Mendonça IL Katz S Barbiéri CL 《Infection and immunity》2005,73(6):3787-3789
High in vitro lymphoproliferative responses were induced in humans and dogs by a recombinant Leishmania (Leishmania) chagasi cysteine proteinase, with secretion of IFN-gamma in asymptomatic subjects or of IFN-gamma, interleukin 4 (IL-4), and IL-10 in oligosymptomatic subjects. In contrast, responses of symptomatic patients and dogs were lower, with production of IL-4 and IL-10. 相似文献
104.
Carl F Weems Alan H Zakem Natalie M Costa Melinda F Cannon Sarah E Watts 《Journal of clinical child and adolescent psychology》2005,34(4):712-723
This study examined the physiological response (skin conductance and heart rate [HR]) of youth exposed to a mildly phobic stimulus (video of a large dog) and its relation to child- and parent-reported anxiety symptoms and cognitive bias in a community-recruited sample of youth (n = 49). The results of this study indicated that HR and skin-conductance response were associated with youth report but not parent report of their child's symptoms of anxiety disorders and that HR response was more strongly associated with anxiety symptoms than skin-conductance response. Physiological response was uniquely associated with youth-reported symptoms of anxiety rather than youth-reported depression. Finally, HR response interacted with cognitive bias in predicting childhood anxiety disorder symptoms in a manner consistent with theories of the etiology of anxiety disorders. 相似文献
105.
C E Bacchi R A Schmidt M Brand?o R Scapulatempo J C Costa F C Schmitt 《Archives of pathology & laboratory medicine》1990,114(8):899-901
We describe a case of paraganglioma arising in the spermatic cord, which is an extremely rare location. Immunohistochemical studies characterized two types of cells: (1) polygonal cells expressing neuron-specific enolase, chromogranin A, and synaptophysin and (2) S100 protein-positive sustentacular cells. Electron microscopy revealed that within the cytoplasm of the polygonal cells, there were electron-dense granules whose morphological appearance was consistent with that of neurosecretory granules. Paraganglioma of the spermatic cord may originate from embryonic chromaffin cells that have followed the testis into the scrotum. 相似文献
106.
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
107.
Reinaldo B Bestetti José Roberto Costa Marot Ulysses B Stella Luiz A P Finzi 《Cardiovascular pathology》2003,12(3):163-165
A 52-year-old man presented with heart failure of 1 month duration. He had undergone aortic valve and root replacement 30 months before admission. A continuous murmur was heard in the second intercostal space at the parasternal border. Aortography showed a pseudoaneurysm surrounding the aorta, whereas color Doppler study revealed flow from the central aorta to the pseudoaneurysm and flow from the pseudoaneurysm to the pulmonary artery trunk through a fistulous communication between them. Thus, fistulous communication with pulmonary artery causing heart failure is a complication of pseudoaneurysm after aortic and root replacement, which can be diagnosed clinically and echocardiographically. 相似文献
108.
Kaufmann H Biaggioni I Voustianiouk A Diedrich A Costa F Clarke R Gizzi M Raphan T Cohen B 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,143(4):463-469
It has been proposed that a vestibular reflex originating in the otolith organs and other body graviceptors modulates sympathetic activity during changes in posture with regard to gravity. To test this hypothesis, we selectively stimulated otolith and body graviceptors sinusoidally along different head axes in the coronal plane with off-vertical axis rotation (OVAR) and recorded sympathetic efferent activity in the peroneal nerve (muscle sympathetic nerve activity, MSNA), blood pressure, heart rate, and respiratory rate. All parameters were entrained during OVAR at the frequency of rotation, with MSNA increasing in nose-up positions during forward linear acceleration and decreasing when nose-down. MSNA was correlated closely with blood pressure when subjects were within +/-90 degrees of nose-down positions with a delay of 1.4 s, the normal latency of baroreflex-driven changes in MSNA. Thus, in the nose-down position, MSNA was probably driven by baroreflex afferents. In contrast, when subjects were within +/-45 degrees of the nose-up position, i.e., when positive linear acceleration was maximal along the naso-ocipital axis, MSNA was closely related to gravitational acceleration at a latency of 0.4 s. This delay is too short for MSNA changes to be mediated by the baroreflex, but it is compatible with the delay of a response originating in the vestibular system. We postulate that a vestibulosympathetic reflex, probably originating mainly in the otolith organs, contributes to blood pressure maintenance during forward linear acceleration. Because of its short latency, this reflex may be one of the earliest mechanisms to sustain blood pressure upon standing. 相似文献
109.
Real-time PCR for diagnosis and follow-up of Toxoplasma reactivation after allogeneic stem cell transplantation using fluorescence resonance energy transfer hybridization probes 总被引:21,自引:0,他引:21
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Costa JM Pautas C Ernault P Foulet F Cordonnier C Bretagne S 《Journal of clinical microbiology》2000,38(8):2929-2932
Toxoplasma reactivation is a life-threatening complication of allogeneic stem cell transplantation. A poor prognosis is probably linked to a difficult diagnosis, based on the detection of evidence of parasites in tissue. We developed a real-time PCR test using fluorescence resonance energy transfer hybridization probes to detect and quantify Toxoplasma gondii DNA in serum. This PCR test gave reproducible quantitative results over a dynamic range of from 0.75 x 10(6) to 0.75 parasites per PCR mixture. Serial samples from four patients with toxoplasma reactivation were evaluated. Three patients had several consecutive PCR-positive samples which corresponded to =0.75 parasites. These three patients became PCR negative during trimethoprim-sulfamethoxazole therapy but never developed clinically apparent toxoplasmosis. In contrast, one patient had an increasing PCR signal, from 1 to 396 parasites in 12 days, and developed cerebral symptoms. The parasite count decreased to 5 parasites in 3 days after pyrimethamine-clindamycin treatment. Real-time quantitative PCR is useful for diagnosis and follow-up of toxoplasma reactivation. 相似文献
110.
M Tsokos R Howard J Costa 《Laboratory investigation; a journal of technical methods and pathology》1983,48(2):148-155
Paraffin-embedded sections of 11 alveolar and 12 embryonal rhabdomyosarcomas, 12 lymphomas, five neuroblastomas, five extraskeletal neoplasms resembling Ewing's sarcoma, and six epithelial tumors were tested for immunoreactivity against myosin, myoglobin, and isozymes BB and MM of creatine kinase with a peroxidase-antiperoxidase method. Of the 23 cases of rhabdomyosarcomas 17 were positive for at least three of the antigenic determinants. In contrast, the other investigated tumors were consistently negative for all markers, with the exception of breast and prostatic carcinomas. Our results establish that the presence of three or four of the above markers in a tumor is strongly suggestive of a rhabdomyosarcoma and helpful in the distinction of alveolar and embryonal rhabdomyosarcomas from lymphomas, neuroblastomas, and extraskeletal neoplasms resembling Ewing's sarcoma. 相似文献