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91.
Enrique E Pineda F Malek T Bartra J Basagaña M Tella R Castelló JV Alonso R de Mateo JA Cerdá-Trias T San Miguel-Moncín Mdel M Monzón S García M Palacios R Cisteró-Bahíma A 《The Journal of allergy and clinical immunology》2005,116(5):1073-1079
BACKGROUND: Food allergy may be life-threatening, and patients affected need to receive accurate diagnoses and treatment. Hazelnut has often been implicated as responsible for allergic reactions, and trace quantities can induce systemic reactions. OBJECTIVE: The aim of this study was to evaluate the efficacy and tolerance of sublingual immunotherapy with a standardized hazelnut extract in patients allergic to hazelnut. METHODS: This was a randomized, double-blind, placebo-controlled study. Inclusion criteria were a history of hazelnut allergy and positive skin prick test and double-blind placebo-controlled food challenge results. Patients were then randomly assigned into 2 treatment groups (hazelnut immunotherapy or placebo). Efficacy was assessed by double-blind, placebo-controlled food challenge after 8 to 12 weeks of treatment. Blood samples were drawn for measurement of specific IgE, IgG(4), and serum cytokines before and after treatment. RESULTS: Twenty-three patients were enrolled and divided into 2 treatment groups. Twenty-two patients reached the planned maximum dose at 4 days. Systemic reactions were observed in only 0.2% of the total doses administered. Mean hazelnut quantity provoking objective symptoms increased from 2.29 g to 11.56 g (P = .02; active group) versus 3.49 g to 4.14 g (placebo; NS). Moreover, almost 50% of patients who underwent active treatment reached the highest dose (20 g), but only 9% in the placebo. Laboratory data showed an increase in IgG(4) and IL-10 levels after immunotherapy in only the active group. CONCLUSION: Our data confirm significant increases in tolerance to hazelnut after sublingual immunotherapy as assessed by double-blind, placebo-controlled food challenge, and good tolerance to this treatment. 相似文献
92.
Ricardo Pietrobon Anand Shah Paul Kuo Matthew Harker Mariana McCready Christeen Butler Henrique Martins CT Moorman Danny O Jacobs 《BMC medical informatics and decision making》2006,6(1):32-11
Background
Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process. 相似文献93.
Jorge A. Negroni Elena C. Lascano Ricardo H. Pichel 《Annals of biomedical engineering》1987,15(1):35-50
We undertook a theoretical analysis of the source resistance of the left ventricle represented in a mean pressure-mean flow
diagram, using the chamber properties established in terms of the pressure-volume relationship. This analysis showed that
pairs of points should lie above the linear function proposed by Elzinga and Westerhof. A third-order polynomial function
would theoretically explain better than a linear relation or a parabolic fit the curved shape of experimentally obtained
relationships. The analysis resolves the discrepancy between Elzinga and Westerhof's theoretical concept of linear source
resistance and the actual nonlinear
relationship. 相似文献
94.
Ricardo A. Maselli Hélio van der Linden Jr Michael Ferns 《American journal of medical genetics. Part A》2020,182(7):1744-1749
Defects in the gene encoding synaptotagmin 2 (SYT2) have been linked to a presynaptic congenital myasthenic syndrome (CMS) and motor neuropathies. However, to date only dominant forms of the disease have been described. We report here a consanguineous patient with a severe recessive form of presynaptic CMS and denervation atrophy caused by the homozygous mutation c.1191delG, p.Arg397Serfs*37 in SYT2. The affected 2‐year‐old girl had profound weakness and areflexia with moderate bulbar deficit. Repetitive nerve stimulation revealed an extreme reduction of compound muscle action potential amplitudes at rest, with a striking facilitation followed by a progressive decline at fast stimulation rates. These findings were reminiscent, but not identical to those seen in the Lambert–Eaton myasthenic syndrome. 3,4 diaminopyridine and pyridostigmine were effective to ameliorate muscle fatigue, but albuterol was ineffective. Modeling of the mutation using the rat Syt1 C2B x‐ray structure revealed that Arg397Serfs*37 disrupts a highly conserved amino acid sequence at the bottom face of the C2B domain not directly involved in calcium binding, but crucial for synaptotagmin‐SNARE interaction and exocytosis. Thus, this report describes a recessive form of synaptotagmin 2‐CMS and highlights the importance of the synaptotagmin C‐terminal on synaptic vesicle fusion and exocytosis. 相似文献
95.
Ricardo Baptista Hugo Silva Miguel Rocha 《Journal of medical engineering & technology》2020,44(4):153-161
AbstractThe stethoscope is a major symbol of modern medicine. It is used for diagnosis of different conditions and enables physicians to listen to internal body sounds. Electrocardiography was only introduced in medicine in the beginning of the twentieth century. Today measuring heart’s electrical activity is also fundamental cardiac diseases diagnosis. Although performed with independent devices, requiring physician and patient presence in the same physical space, in combination they enhance cardiovascular assessment. In this paper, a digital stethoscope encapsulation was designed, adding new functionality to this advanced medical device. Today wired and wireless communications enable different medical devices to share data and information, over long distances. Using low-cost hardware technologies, the encapsulation will add the ability to acquire and transmit via Bluetooth the Electrocardiographic activity, determined in the same cardiac focus and synchronised with the Phonocardiographic sound recordings. Several encapsulation concepts were developed and prototyped using 3D printing. They were easily fitted to the digital stethoscope and tested in a hospital environment for ergonomics, acoustic and electric signals acquisition. The best concept was chosen with the help of a physician’s opinion and the final prototype performance was very satisfactory. 相似文献
96.
Sierra C Lascurain R Pereyra A Guevara J Martínez G Agundis C Zenteno E Vázquez L 《Developmental and comparative immunology》2005,29(2):113-121
Using a spectrophotometric NBT reduction assay and phagocytosis, we identified that production of superoxide anions and phagocytic activity of hemocytes from Macrobrachium rosenbergii were significantly higher in the presence of rat, rabbit, and chicken erythrocytes than with human, pig, or horse erythrocytes. Hemocytes stimulated with MrL, MrLMab, or PMA increased 4.7, 5.1, and 6.1 fold, respectively, the oxidative response as compared to non-stimulated hemocytes. MrLMab together with MrL increased 5.7 fold the oxidative capacity of hemocytes as compared to non-stimulated cells. These effects were inhibited with 100 mM GalNAc, GlcNAc, or Neu5Ac and 0.2 microM of sialylated submaxillary gland mucin and fetuin. Piroxicam inhibited (P < 0.05) the production of O(2)(-) induced by MrL, whereas iodoacetamide inhibited the effect of MrLMAb (P < 0.05) in a dose-dependent manner. Our results suggest that MrLMab might activate the oxidative burst through the metabolism of glucose as opposed to MrL which utilizes NADPH-independent mechanisms, very probably through pro-inflammatory metabolites. 相似文献
97.
Monsalve-De Castillo F Romero TA Estévez J Costa LL Atencio R Porto L Callejas D 《Clinical and diagnostic laboratory immunology》2002,9(6):1372-1375
The immunoregulatory roles of interleukin-2 (IL-2), IL-4, IL-10, gamma interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), the soluble form of the IL-2 receptor (sIL-2R), and the soluble form of CD30 (sCD30) were evaluated in patients with hepatitis B virus (HBV) infection. Two groups of subjects were studied: 15 healthy individuals without hepatitis antecedents and 15 patients with HBV infection. Blood samples were taken during the acute and convalescent phases. The analysis of the samples was done by the enzyme-linked immunosorbent assay technique. IFN-gamma and TNF-alpha levels decreased in the convalescent phase. IL-10, IL-2, and sIL-2R levels increased in the acute and convalescent phases, while sCD30 levels increased during the acute phase. The IL-4 concentrations decreased in both phases. During the acute phase, IFN-gamma and TNF-alpha induced increases in IL-2, sIL-2R, IL-10, and sCD30 levels in serum, which allowed the development of immunity characterized by the nonreactivity of the HBV surface antigen, the onset of antibodies to the HBV surface antigen (anti-HBs), and normal alanine aminotransferase levels during the convalescent phase. Increased IL-2 levels during the acute phase would stimulate the activities of NK cells and CD8(+) lymphocytes, which are responsible for viral clearing. The raised sIL-2R levels reveal activation of T lymphocytes and control of the IL-2-dependent immune response. The sCD30 increment during the acute phase reflects the greater activation of the Th2 cellular phenotype. Its decrease in the convalescent phase points out the decrease in the level of HBV replication. The increase in IL-10 levels could result in a decrease in IL-4 levels and modulate IFN-gamma and TNF-alpha levels during both phases of disease, allowing the maintenance of anti-HBs concentrations. 相似文献
98.
García-Samaniego J Soriano V Miró JM Romero JD Bruguera M Castilla J Esteban JI Gonźlez J Lissen E Moreno A Moreno S Moreno-Otero R Ortega E Quereda C Rodríguez M Sánchez-Tapias JM;Spanish Hepatitis-HIV Consensus Panel 《HIV clinical trials》2002,3(2):99-114
Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed. 相似文献
99.
The histopathology of papillary thyroid hyperplasia and papillary thyroid carcinoma is similar enough to cause a diagnostic
dilemma in a few cases. Both lesions may have papillary fronds with fibrovascular cores, nuclear crowding, and nuclear anisocytosis.
Formalin-fixed paraffin-embedded tissues from 30 randomly selected patients with papillary thyroid hyperplasia and an equal
number from patients with papillary thyroid carcinoma were analyzed for expression of cytokeratin 19 (CK19), galectin-3, and
HBME-1. Cases of papillary thyroid carcinoma had moderate to strong CK19, galectin-3, and HBME-1 reactivity although both
CK19 and galectin-3 showed positive staining in a significant number of nonneoplastic thyroid cases. HBME-1 was uncommon in
the nonneoplastic cases. These results indicate that HBME-1 may be useful in helping to distinguish papillary thyroid carcinoma
from hyperplasia in diagnostically difficult cases. 相似文献
100.
Risk factors for incident HIV infection among anonymous HIV testing site clients in Santos,Brazil: 1996-1999 总被引:1,自引:0,他引:1
Alves K Shafer KP Caseiro M Rutherford G Falcao ME Sucupira MC Busch MP Rawal BD Diaz RS 《Journal of acquired immune deficiency syndromes (1999)》2003,32(5):551-559
OBJECTIVES: To determine temporal trends in HIV infection and risk factors among persons seeking anonymous HIV testing in Santos, Brazil. METHODS: Data and sera from persons testing for HIV from 1996 to 1999 were used. Exposures were abstracted from HIV testing risk assessments. Stored HIV-positive sera were tested to identify recently acquired HIV infection using a serologic testing algorithm for detecting recent HIV seroconversion (STARHS). Independent associations between exposures and recently acquired HIV infection were determined using multivariate analyses. RESULTS: Overall, estimated HIV incidence was 2.0% (95% CI: 1.1-3.5) for the 4-year period: 1.2% (95% CI: 0.5-2.6) in women and 2.7% (95% CI: 1.3-5.0) in men. Incidence increased among women but remained stable among men. Exposures independently associated with incident infection included a history of sex work (OR= 5.4, 95% CI: 1.5-18.7), concurrent syphilis infection (OR =4.1, 95% CI: 1.4-11.9), anal sex (OR = 3.0, 95% CI: 1.3-7.1), and having an HIV-positive sexual partner (OR= 1.4, 95% CI: 1.1-1.9). CONCLUSIONS: This study further demonstrates the public health utility of using the STARHS for the assessment of emerging trends in the HIV epidemic. Results from this study will help to target appropriate prevention strategies directed toward at-risk populations in Santos. 相似文献