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Iron-doped bismuth sulphide (Bi2-xFexS3) nanocrystals have been successfully synthesized in a glass matrix using the fusion method. Transmission electron microscopy images and energy dispersive spectroscopy data clearly show that nanocrystals are formed with an average diameter of 7-9 nm, depending on the thermic treatment time, and contain Fe in their chemical composition. Magnetic force microscopy measurements show magnetic phase contrast patterns, providing further evidence of Fe incorporation in the nanocrystal structure. The electron paramagnetic resonance spectra displayed Fe3+ typical characteristics, with spin of 5/2 in the 3d5 electronic state, thereby confirming the expected trivalent state of Fe ions in the Bi2S3 host structure. Results from the spin polarized density functional theory simulations, for the bulk Fe-doped Bi2S3 counterpart, corroborate the experimental fact that the volume of the unit cell decreases with Fe substitutionally doping at Bi1 and Bi2 sites. The Bader charge analysis indicated a pseudo valency charge of 1.322|e| on FeBi1 and 1.306|e| on FeBi2 ions, and a spin contribution for the magnetic moment of 5.0 µB per unit cell containing one Fe atom. Electronic band structures showed that the (indirect) band gap changes from 1.17 eV for Bi2S3 bulk to 0.71 eV (0.74 eV) for Bi2S3:FeBi1 (Bi2S3:FeBi2). These results are compatible with the 3d5 high-spin state of Fe3+, and are in agreement with the experimental results, within the density functional theory accuracy.
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Bismuto/química , Ferro/química , Nanopartículas/química , Sulfetos/química , Espectroscopia de Ressonância de Spin Eletrônica , Vidro , Modelos Teóricos , Tamanho da Partícula , TermodinâmicaRESUMO
INTRODUCTION: Mastocytosis is a clonal haematological disease characterized by uncontrolled proliferation and the activation of mast cells. The value of FDG-PET/CT (FDG-PET) in mastocytosis has yet to be determined. METHODS: We retrospectively identified patients with an established diagnosis of systemic mastocytosis (SM), according to the WHO criteria, who underwent PET using the French Reference Centre for Mastocytosis database. Semi-quantitative and visual analysis of FDG-PET was performed and compared to the clinico-biological data. RESULTS: Our cohort included 19 adult patients, median age 65 years [range 58-74], including three with smouldering SM (SSM), three with aggressive SM (ASM), 10 with an associated clonal haematological non-mast-cell lineage disease (SM-AHNMD), and three with mast cell sarcoma (MCS). FDG-PET was performed at the time of the SM diagnosis (15/19), to evaluate lymph node (LN) activity (3/19) or the efficacy of therapy (1/19). FDG uptake was observed in the bone marrow (BM) (9/19, 47%), LN (6/19, 32%), spleen (12/19, 63%), or liver (1/19, 5%). No significant FDG uptake was observed in the SSM and ASM patients. A pathological FDG uptake was observed in the BM of 6/10 patients with SM-AHNMD, appearing as diffuse and homogeneous, and in the LN of 5/10 patients. All 3 MCS patients showed intense and multifocal BM pathological uptake, mimicking metastasis. No correlation was found between the FDG-PET findings and serum tryptase levels, BM mast cell infiltration percentage, and CD30 and CD2 expression by mast cells. CONCLUSIONS: FDG uptake does not appear to be a sensitive marker of mast cell activation or proliferation because no significant FDG uptake was observed in most common forms of mastocytosis (notably purely aggressive SM). However, pathological FDG uptake was observed in the SM-AHNMD and in MCS cases, suggesting a role of FDG-PET in their early identification and as a tool of therapeutic assessment in this subgroup of patients.
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Mastocitose Sistêmica/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Idoso , Feminino , Fluordesoxiglucose F18 , França , Humanos , Masculino , Pessoa de Meia-Idade , Compostos RadiofarmacêuticosRESUMO
Large vessel involvement in ANCA-associated vasculitis is very rare. We report here on the case of two patients with ANCA-associated vasculitis and asymptomatic aortic arch involvement diagnosed using FDG-PET/CT. Because aortic involvement in ANCA-associated vasculitis is a potentially life-threatening condition, its early detection can be crucial. FDG-PET/CT may also provide new insights into large vessel involvement as part of the spectrum of ANCA-associated vasculitis.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Fluordesoxiglucose F18 , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Corticosteroides/uso terapêutico , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Aortografia/métodos , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
BACKGROUND: The ideal hypnotic agent for electroconvulsive therapy (ECT) is still under debate and previous studies comparing etomidate and methohexital have produced conflicting results. This retrospective study compares etomidate and methohexital as anesthetic agents in continuation and maintenance (m)ECT with regard to seizure quality and anesthetic outcomes. METHODS: All subjects undergoing mECT at our department between October 1st, 2014 and February 28th, 2022 were included in this retrospective analysis. Data for each ECT session were obtained from the electronic health records. Anesthesia was performed with either methohexital/succinylcholine or etomidate/succinylcholine. Standard seizure quality parameters, anesthesiological monitoring data, pharmacological interventions and side-effects were recorded. RESULTS: 573 mECT treatments in 88 patients were included (methohexital n = 458, etomidate n = 115). Seizures lasted significantly longer after using etomidate (electroencephalography: +12.80 s [95 %-CI:8.64-16.95]; electromyogram +6.59 s [95 %-CI:4.14-9.04]). Time to maximum coherence was significantly longer with etomidate (+7.34 s [95 %-CI:3.97-10.71]. Use of etomidate was associated with longer procedure duration (+6.51 min [95 %-CI:4.84-8.17]) and higher maximum postictal systolic blood pressure (+13.64 mmHg [95 %-CI:9.33-17.94]). Postictal systolic blood pressure > 180 mmHg, the use of antihypertensives, benzodiazepines and clonidine (for postictal agitation), as well as the occurrence of myoclonus was significantly more common under etomidate. CONCLUSIONS: Due to longer procedure duration and an unfavorable side effect profile, etomidate appears inferior to methohexital as an anesthetic agent in mECT despite longer seizure durations.
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Eletroconvulsoterapia , Etomidato , Humanos , Etomidato/efeitos adversos , Metoexital/uso terapêutico , Estudos Retrospectivos , Anestésicos Intravenosos/efeitos adversos , Eletroconvulsoterapia/efeitos adversos , Eletroconvulsoterapia/métodos , Succinilcolina/uso terapêutico , Convulsões/terapia , Convulsões/induzido quimicamente , EletroencefalografiaRESUMO
Findings from animal studies have suggested that bone remodeling is under beta-adrenergic control. However, the level of adrenergic inhibition required to achieve the most favorable effects on the skeleton remains unknown. To address this question, we compared the effects of low (0.1 mg/Kg/day), medium (5 mg/Kg/day) or high (20 mg/Kg/day) doses of propranolol given 5 days per week for 10 weeks in ovariectomized (OVX) rats. Characteristics of bone microarchitecture, biomechanical properties and bone turnover were investigated, whilst heart functions were assessed by echocardiography and catheterization of the left ventricle. We first confirmed the expression of Adrbeta2R and the absence of Adrbeta1R on osteoblasts by PCR and confocal microscopy. We then showed that low dose propranolol prevented OVX induced bone loss by increasing bone formation (+30% of MAR vs. placebo, P = 0.01) and decreasing bone resorption (-52% of osteoclast surface on bone surface vs. placebo, P = 0.01). Consequently, rats receiving 0.1 mg/kg/day propranolol displayed higher stress (+27%), intrinsic energy (+28.7%) and Young's Modulus in compression versus placebo (all, P < 0.05). No significant effects on heart hemodynamic parameters were found in rats receiving this dose. In contrast, medium and high doses of propranolol had a negative effect on heart functions but no significant protective effects on bone mass in ovariectomized rats. These results, consistent with the dominant nature of the high bone mass phenotype and normal heart function of Adrbeta2R-deficient mice, suggest that low doses of beta-blockers may have a therapeutic utility in the treatment of osteoporosis with high selectivity for bone tissues.
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Antagonistas Adrenérgicos beta/administração & dosagem , Antagonistas Adrenérgicos beta/uso terapêutico , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/prevenção & controle , Coração/fisiopatologia , Propranolol/administração & dosagem , Propranolol/uso terapêutico , Antagonistas Adrenérgicos beta/farmacologia , Animais , Fenômenos Biomecânicos , Pressão Sanguínea/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea/fisiopatologia , Relação Dose-Resposta a Droga , Ecocardiografia , Feminino , Fêmur/efeitos dos fármacos , Fêmur/fisiopatologia , Coração/efeitos dos fármacos , Testes de Função Cardíaca , Frequência Cardíaca/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/metabolismo , Microscopia Confocal , Osteocalcina/sangue , Ovariectomia , Reação em Cadeia da Polimerase , Propranolol/farmacologia , Ratos , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/fisiopatologia , Tíbia/efeitos dos fármacos , Tíbia/fisiopatologiaRESUMO
OBJECTIVES: To establish normative data for ophthalmic artery Doppler parameters throughout a healthy pregnancy, to investigate the possible correlation between these Doppler measurements and gestational age, and to test intraobserver variability. METHODS: A prospective cross-sectional study was performed to assess various Doppler parameters in 276 healthy women between 20 and 39 weeks of gestation. The following measurements were obtained: pulsatility and resistance indices (PI, RI), peak systolic velocity (PSV), peak diastolic velocity (PDV), end diastolic flow velocity (EDFV), and peak ratio (PR). Quantile regression was used to estimate reference values throughout pregnancy and P<0.05 was considered significant. The intraclass correlation coefficient (Intra-CC) was used to calculate intraobserver variability. RESULTS: The 5th and 95th prediction intervals for each gestational age are presented. No significant correlation was detected between Doppler indices and gestational age. Intra-CC was excellent (0.996). CONCLUSIONS: Reference values were generated for ophthalmic artery Doppler measurements, and they did not vary significantly during healthy pregnancy.
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Fluxometria por Laser-Doppler , Artéria Oftálmica/fisiologia , Gravidez/fisiologia , Estudos Transversais , Feminino , Idade Gestacional , Humanos , Variações Dependentes do Observador , Estudos Prospectivos , Valores de ReferênciaRESUMO
The etiological structure of influenza and other acute respiratory viral infections including their rate of incidence in St. Petersburg and Leningrad region during 4 epidemic seasons has been studied. Seasonality of some respiratory viruses was shown and peaks of circulation of RSV, adenovirus, parainfluenza viruses, rhinovirus, bocavirus, metapneumovirus and coronavirus were marked. The interference of influenza A viruses and RSV, RSV and rhinoviruses was highlighted. A high incidence of adenovirus infection in organized communities and RSV infection in children was revealed.
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Infecções por Adenovirus Humanos/epidemiologia , Influenza Humana/epidemiologia , Infecções por Paramyxoviridae/epidemiologia , Infecções Respiratórias/epidemiologia , Adenoviridae/patogenicidade , Infecções por Adenovirus Humanos/virologia , Adolescente , Bocavirus/patogenicidade , Criança , Coronavirus/patogenicidade , Epidemias , Humanos , Lactente , Vírus da Influenza A/patogenicidade , Influenza Humana/virologia , Metapneumovirus/patogenicidade , Infecções por Paramyxoviridae/virologia , Vírus Sinciciais Respiratórios/classificação , Vírus Sinciciais Respiratórios/patogenicidade , Infecções Respiratórias/virologia , Rhinovirus/patogenicidade , Federação Russa/epidemiologia , Estações do AnoRESUMO
Introducción. Los tumores neoplásicos se caracterizan por su invasividad y metástasis. Las células neoplásicas tienen heterogeneidad genética, por lo cual pueden desarrollar resistencia a los quimioterápicos. Por esta razón, las plantas continúan siendo una fuente importante de nuevos productos anticancerígenos. Objetivo. Evaluar la actividad citotóxica y antiproliferativa de un extracto rico en fucoidan de Lessonia trabeculata nativa (EFLt) sobre la línea celular de adenocarcinoma mamario murino, triple negativo 4T1. Métodos. La citotoxicidad y la IC50 se determinaron en monocapas de 4T1 empleando el reactivo MTT. Para demostrar la actividad antiproliferativa se aplicaron los métodos de cierre de herida y anticlonogénico utilizando las IC50 del EFLt y Dox (doxorubicina). El cierre de herida fue evaluado mediante barrido de tiempos discretos; el efecto anticlonogénico fue evaluado 7 días postratamiento mediante el conteo de colonias y se determinó la fracción de sobrevivencia. Adicionalmente, se evaluaron la citotoxicidad y actividad antiproliferativa combinando las IC50 de EFLt y Dox. El porcentaje de migración y conteo de colonias se realizó con el programa ImageJ. Resultados. La IC50 del EFLt (950 μg/mL) produjo 56% de citotoxicidad, 80,3% de inhibición de la migración celular, 68% de inhibición en la formación de colonias. La IC50 de Dox fue 0,5 μg/mL. Conclusiones. El EFLt ejerce citotoxicidad dependiente de la concentración y tiene efecto antiproliferativo sobre 4T1. Se requiere continuar los ensayos en modelos de mayor complejidad que permitan esclarecer el potencial antitumoral del EFLt.
Introduction. Neoplastic tumors are characterized by invasiveness and metastasis. Neoplastic cells are genetically heterogeneous and can develop resistance to chemotherapeutic agents. For this reason, plants continue to be an important source of new anticancer products. Objective. To determine the cytotoxic and antiproliferative activity of a fucoidan-rich extract of native Lessonia trabeculata (EFLt) on the tripe negative murine mammary adenocarcinoma cell line 4T1. Methods. Cytotoxicity and IC50 were determined in 4T1 monolayers using the MTT reagent. To demonstrate antiproliferative activity, "wound" closure and anticlonogenic methods were applied using the IC50 of EFLt and Doc (doxorubicin). "Wound" closure was evaluated by discrete times sweep to determine percentage inhibition of cell migration; the anticlonogenic effect was evaluated by colony counting 7 days after treatment and the survival fraction was determined. In addition, cytotoxicity and antiproliferative activity were evaluated by combining the IC50 of EFLt and Dox. Percent migration and colony counts were performed using ImageJ software. Results. The IC50 (950 μg/mL) of EFLt was 56% cytotoxicity, 80,3% inhibition of cell migration, 68% inhibition of colony formation.The ICof Dox was 0,5 μg/mL. Conclusions. EFLt exerts concentration-dependent cytotoxicity and antiproliferative effect on 4T1. Further studies in more complex models are needed to elucidate the anti-tumor potential of EFLt.
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The contribution of adenovirus (AV) infections to the overall structure of acute viral respiratory infections among young people of draft age can reach as high as 64.6%. Wide dissemination, the incidence of AV-associated pneumonias and lethal outcomes in the case of some complicated infections illustrate the urgency of studying the antigenic diversity of AVs circulating among the military. 991 nasopharyngeal swabs from patients hospitalized in military health facilities with symptoms of acute respiratory infections from 2014 to 2017 were detected by real-time PCR. Sanger sequencing was performed using forward and reverse primers matching the fiber gene. AVs were detected in 326 samples. In 80 of those, AVs were present in combination with other respiratory viruses, as follows: 26 with respiratory syncytial viruses (RSV), 49 with rhinoviruses, 2 with bocaviruses, 1 with RSV and rhinovirus, 1 with parainfluenza virus, and 1 with metapneumovirus. 31 samples were sequenced. Thirty AVs belonged to group E (serotype 4), and 1 AV belonged to group B (serotype 7).
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The precise role of pulmonary hypertension as a possible factor inducing a decrease in heart rate variability is poorly known. Spectral analysis of heart rate variability (HRV) was carried out in 21 Wistar rats before and after exposure to normoxia (N = 10) or to 3 weeks of hypobaric hypoxia inducing chronic pulmonary hypertension and right ventricular hypertrophy (N= 11). Continuous ECG was recorded in conscious animal at rest. Compared to the control group, rats exposed to hypoxia had a similar heart rate but a lower overall HRV (total power, 27.9 +/- 15.2 vs. 57.6 +/- 24.7 ms2, P < 0.01). Low frequency power (0.25-0.8 Hz) and high frequency power (0.8-3 Hz) were similar in both groups suggesting that HRV was decreased in the very low frequency power (0-0.25 Hz). The effects of atropine and propranolol on heart rate and HRV were similar in rats exposed or not to hypoxia. HRV is decreased in rats with hypoxic induced pulmonary hypertension, mainly in the very low frequency band, suggesting an increase in sympathetic activity. However, this decrease is moderate and the modulation of HRV with pharmacologic autonomic blockade remains similar to that of normal rats.
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Frequência Cardíaca , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Hipóxia/complicações , Animais , Doença Crônica , Masculino , Ratos , Ratos WistarRESUMO
INTRODUCTION: In a discordant orthotopic xenotransplantation model (pig-to-baboon) donor pigs expressing human decay accelerating factor (hDAF) as a regulator of complement activity were used to prevent hyperacute xenograft rejection (HXR). We investigated a modified immunosuppressive therapy consisting of ERL080 (Novartis Pharma AG, Base, Switzerland), cyclosporin A (Neoral), steroids, and a cyclophosphamide (CyP) induction protocol with several reduced doses to prevent acute vascular rejection (AVR). METHODS: Donor hearts were harvested from hDAF-transgenic pigs (18.8 +/- 2.6 kg, Imutran Ltd., a Novartis Pharma AG Company). Four adult baboons (25.6 +/- 2.7 kg) with high titers of xenoreactive antibodies (XAb) served as recipients. Serological and hemodynamic parameters were measured. Finally, myocardial tissue was sampled for histological and immunohistochemical examinations. RESULTS: In the first baboon, an acute graft failure occurred after 1 hour due to preservation injury. The second succumbed after 11.1 day due to an acute renal failure. The third died after 13.1 days of an ileus. The fourth baboon had continuously excellent cardiac function (mean echocardiographic ejection fraction, 69.2%), but succumbed on day 20 due to anemia. Corrected mean xenograft survival (excluding the first baboon because of a technical failure) was 14.6 +/- 2.6 days. XAb decreased after day 3 to constantly low levels (<1:64 titer) after CyP induction. White blood cell count decreased from 10.3 +/- 0.8 to 0.9 +/- 0.3 G/L after day 3. Macroscopically and histologically no typical signs of HXR or severe AVR could be detected. CONCLUSIONS: These results confirm that hDAF transgen blocks HXR in this life-supporting model. AVR was prevented by using a modified quadruple immunosuppressive drug combination (Neoral, ERL080, steroids, and several small single doses of CyP). An optimum "fine-tuning" of immunosuppression is required to achieve the best risk-benefit ratio.
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Antígenos CD55/genética , Sobrevivência de Enxerto/fisiologia , Transplante de Coração/fisiologia , Células de Sertoli/transplante , Transplante Heterólogo/fisiologia , Animais , Animais Geneticamente Modificados , Anticorpos Heterófilos/sangue , Transplante de Coração/métodos , Hemodinâmica , Humanos , Masculino , Papio , Ratos , Ratos Sprague-Dawley , Suínos , Fatores de Tempo , Transplante Heterólogo/métodosRESUMO
INTRODUCTION: Hyperacute xenograft rejection (HXR) and acute vascular rejection (AVR) after xenotransplantation are triggered by xenoreactive antibodies (XAb) and an activated complement cascade. In a heterotopic (abdominal) xenotransplantation model we combined immunoadsorption (IA, Ig-Therasorb column) and a quadruple immunosuppressive drug therapy in recipient baboons with donor pig hearts transgenic for human decay accelerating factor (hDAF). METHODS: According to XAb titers between 6 and 14 cycles of IA were performed preoperatively in 4 recipient baboons (18.6 +/- 2.5 kg). Hearts of hDAF-transgenic donor pigs (6.1 +/- 1.1 kg, Imutran Ltd., a Novartis Pharma AG Company, Basel, Switzerland) were heterotopically transplanted using the abdominal technique in baboons. Immunosuppression consisted of cyclophosphamide (CyP) induction therapy, ERL080 (Novartis Pharma AG), cyclosporin A (CyA, Neoral), and steroids. Blood levels of mycophenolate, CyA, immunoglobulins (Ig), anti-pig-antibodies, complement factors, and cardiac enzymes were determined. Abdominal electrocardiography (ECG), echocardiography, and palpation were used for monitoring of the pig hearts. Myocardial tissue specimens were examined using immunohistochemistry, light microscope (LM), and electron microscope (EM). RESULTS: Ten cycles of IA alone removed 78% of XAb and accordingly IgM, IgG, IgA, complement C3, and C4. None of the xenografts was hyperacutely rejected, but xenograft failure occurred after 5.0 +/- 1.3 days (range, 2.4-8.0 days) because of an AVR associated with a rapid XAb increase within 24 hours. White blood cell count (10.3 +/- 2.2 G/L) showed a maximum of 13.1 +/- 2.1 (day 1) and constant levels (1.4 +/- 0.3-2.1 +/- 1.3 G/L) between day 3 and 6. Histology (LM/EM) showed massive hemorrhage, necrosis, and vascular thrombi as signs of AVR. CONCLUSION: Although HXR was prevented by using IA and hDAF-transgenic donor hearts, AVR was not avoided due to insufficient immunosuppressive regimen used and a missed postoperative IA treatment as a result of an inefficient control of XAb production.
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Antígenos CD55/genética , Transplante de Coração/imunologia , Corticosteroides/uso terapêutico , Animais , Animais Geneticamente Modificados , Anticorpos Heterófilos/sangue , Humanos , Técnicas de Imunoadsorção , Imunossupressores/uso terapêutico , Ácido Micofenólico/uso terapêutico , Papio , Suínos , Transplante HeterólogoRESUMO
BACKGROUND: The major problem of xenotransplantation is, that hyperacute xenograft rejection (HXR) causes graft failure within minutes or a few hours because of natural antibodies and activation of the complement system. As a preclinical model we transplanted pig hearts orthotopically into baboons. To prevent HXR after orthotopic xenotransplantation (oXHTx), the immunoglobulins (Ig) and natural antibodies were adsorbed to reusable Ig-Therasorb immunoadsorption (IA) columns. METHODS: We performed three oXHTx of landrace pig hearts into baboons (19+/-6.8 kg), using extracorporeal circulation (ECC) connected to the IA unit. After separating the recipient's blood into plasma and cellular fraction by a plasma filter, plasma flow was directed to the Ig-Therasorb column coated with polyclonal sheep-antibodies against human IgG, IgM, and IgA. Intraoperative treatment consisted of 4 cycles of IA. For a control, we transplanted one pig heart into a baboon (16.9 kg) without applying IA. Perioperatively, serum concentrations of Ig, anti-pig-antibodies, complement and cardiac enzymes were determined. Tissue samples of myocardium were collected at the end of the study for immunohistochemical examinations, light microscopic examination (LM) and electron microscopic examination (EM). For cardiac monitoring after oXHTx, we used ECG, echocardiography, and invasive measurement of cardiac output. To prevent a mismatch of donor and recipient heart size, the donor pig had a 30-40% lower body weight than the recipient baboon. RESULTS: Four cycles of IA removed >80% of IgG, IgM, and IgA from plasma. The graft of the control animal failed after 29 min. The first oXHTx with IA was intentionally terminated after 100 min, the second oXHTx after 11 hr and the third oXHTx after 21 hr. All xenografts showed no histological signs of HXR. After weaning off ECC, these donor hearts worked in sinus rhythm without electrocardiographic ST-segment elevation. An excellent cardiac output was measured by echocardiography and thermodilution (2 L/min). Serological parameters indicating cardiac damage were significantly lower after IA if compared with the control experiment. Macroscopically, the xenograft of the control animal showed massive hemorrhage in comparison with the almost inconspicuous grafts after IA. The myocardium of the IA group demonstrated fewer deposits of Ig and complement components compared with the control animal. CONCLUSION: Baboons do not hyperacutely reject a porcine xenograft after antibody depletion by the Ig-Therasorb column. In our experiment only 4 cycles of immunoapheresis effectively prevented HXR after oXHTx of baboons. The Ig-Therasorb column is a reusable device, which can be handled easily in combination with the ECC. IA must be tested in oXHTx longterm survival experiments, especially in combination with transgenic pig organs, which could be a reliable preclinical approach for future clinical xenotransplantation.
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Transplante de Coração/imunologia , Imunoglobulinas/sangue , Técnicas de Imunoadsorção , Transplante Heterólogo , Animais , Anticorpos/sangue , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/fisiologia , Testes de Hemaglutinação , Hemodiluição , Hemodinâmica , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imuno-Histoquímica , Microscopia Eletrônica , Miocárdio/química , Miocárdio/ultraestrutura , Papio , Suínos , Transplante Heterólogo/imunologia , Transplante Heterólogo/patologiaRESUMO
To evaluate the diagnostic performance of Fourier phase analysis of gated blood pool single-photon emission computed tomography (GBP SPECT) in arrhythmogenic right ventricular (RV) cardiomyopathy, 18 patients with confirmed arrhythmogenic RV cardiomyopathy underwent GBP SPECT and x-ray cineangiography. Results were compared with data obtained with GBP SPECT in 10 control subjects. This 3-dimensional method demonstrated good correlation with cineangiography for measurements of RV enlargement and extent of the disease; RV and left ventricular segments were analyzed with the same accuracy. Tomographic abnormalities were significant decreased RV ejection fraction, RV dilatation, nonsynchronized contraction of the ventricles, increased RV contraction dispersion, presence of segmental RV wall motion disorders and/or phase delays, and occasionally regional left ventricular abnormalities. RV-delayed phase areas were always present in our population. A scoring system with RV criteria was proposed to diagnose RV disease. Because Fourier analysis of GBP SPECT provides ventricular morphologic information for the right ventricle with the same accuracy as for the left ventricle, it may replace planar radionuclide studies. Therefore, this method is helpful in patients with a strong clinical suspicion of arrhythmogenic RV cardiomyopathy, and should be used as a screening method before right ventriculography.
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Displasia Arritmogênica Ventricular Direita/diagnóstico por imagem , Imagem do Acúmulo Cardíaco de Comporta , Tomografia Computadorizada de Emissão de Fóton Único , Adolescente , Adulto , Idoso , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Cineangiografia , Feminino , Análise de Fourier , Humanos , Masculino , Pessoa de Meia-Idade , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico por imagemRESUMO
PURPOSE: The objective of this study was to evaluate the ability of Doppler tissue imaging (DTI) to localize the ventricular emergence site of accessory atrioventricular pathways (Wolff-Parkinson-White syndrome). METHODS: Thirty-three patients were studied prospectively by Doppler tissue imaging (128XP and Sequoia 256 echocardiographic systems; Acuson, Mountain View, Calif) before investigation of Wolff-Parkinson-White syndrome and after radiofrequency ablation of the accessory pathways. The normal appearance of the ventricular contractions was defined in a group of 10 control subjects. The preexcitation zone was determined as a zone of maximum acceleration in "DTI acceleration mode" or as a coded contraction zone in "DTI velocity mode," at the time of the delta wave or before the onset of the QRS complex. RESULTS: The earliest ventricular activation site was correctly localized for 12 of the 15 left-sided pathways (8 anterior or anterolateral, 2 lateral or posterolateral, 2 inferior). When wall motion abnormalities were detected in the left ventricle by DTI, the left-sided localization was confirmed by electrophysiologic exploration. For the right-sided pathways, the localization was correct in only 4 of 11 cases (3 posteroseptal and 1 anterolateral). After effective ablation in all patients, the abnormalities corresponding to the electrophysiologic data disappeared totally in only 11 of 16 patients. CONCLUSION: In the presence of Wolff-Parkinson-White syndrome, DTI localizes contraction abnormalities associated with early activation of a part of the ventricle. However, the interpretation of the images remains difficult because the normal coding of the contraction of the ventricular walls depends on the incidence for which they are investigated. This noninvasive examination seems to be an effective tool for localizing the left-sided accessory pathways of the left ventricle, in particular in the anterior, anterolateral, or inferior walls.
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Ecocardiografia Doppler em Cores/métodos , Sistema de Condução Cardíaco/diagnóstico por imagem , Síndrome de Wolff-Parkinson-White/diagnóstico por imagem , Adulto , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: The aim of this study was to assess the prognostic value of early brain scintigraphy in head injury in relation to long-term neuropsychological behavior. Twenty-four patients underwent technetium-99m (Tc-99m) ethyl cysteinate dimer single photon emission computed tomography (SPECT) within 1 month of the trauma. Scintigraphic abnormalities were evaluated both visually and semiquantitatively using the brain-to-cerebellum ratio method. The clinical neuropsychological investigation was conducted to evaluate abnormalities related to motor deficit, frontal behavior, and memory and language disorders. All patients had abnormalities on SPECT scan. One year after trauma, 14 patients (58%) had neuropsychological sequelae. The brain-to-cerebellum ratios in the left basal ganglia and brain stem were significantly decreased in patients with memory disorders (P = .03 and P = .02, respectively). Moreover, SPECT visual analysis indicated that low uptake in the basal ganglia, thalamus, and brain stem was associated with subsequent motor deficit, frontal behavior, and language and memory disorders. The authors conclude that brain SPECT can be valuable in predicting the neuropsychological behavior of survivors of severe head injury.
Assuntos
Dano Encefálico Crônico/diagnóstico por imagem , Cisteína/análogos & derivados , Traumatismos Cranianos Fechados/diagnóstico por imagem , Testes Neuropsicológicos , Tomografia Computadorizada de Emissão de Fóton Único , Adolescente , Adulto , Edema Encefálico/diagnóstico por imagem , Mapeamento Encefálico , Hemorragia Cerebral/diagnóstico por imagem , Dominância Cerebral , Feminino , Seguimentos , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Organotecnécio , Prognóstico , Fatores de RiscoRESUMO
The recent introduction of tissue harmonic imaging could resolve the problems related to ultrasound in technically difficult patients by providing a marked improvement in image quality. Tissue harmonics are generated during the transmit phase of the pulse-echo cycle, that is, while the transmitted pulse propagates through tissue. Tissue harmonic images are formed by utilizing the harmonic signals that are generated by tissue and by filtering out the fundamental echo signals that are generated by the transmitted acoustic energy. To achieve this, two processes could be used; one by using filters for fundamental and harmonic imaging and the second using two simultaneous pulses with a 180 degrees difference in phase. The introduction of harmonics allows increased penetration without a loss of detail, by obtaining a clearer image at depth with significantly less compromise to the image quality caused by the use of lower frequencies. This imaging mode could be used in different organs with a heightening of low-contrast lesions through artefact reduction, as well as by the induced greater intrinsic contrast sensitivity of the harmonic imaging mode.
Assuntos
Ultrassonografia/métodos , Acústica , Artefatos , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Ultrassonografia Pré-Natal/métodosRESUMO
The objective of this study was to test if three-dimensional (3-D) ultrasound (US) provides accurate determination of the cardiac volumes and ejection fraction. The 3-D device (Model 1-Volumetrics, ) is a 3-D acquisition system using a 2-Mhz matrix probe that insonates the whole cardiac volume in a 4-chamber view and collects the entire backscattered US echoes from this volume within one cardiac cycle. The complete 3-D US information stored in the memory can then be cut into 2-D views of any arbitrary orientation. For volume determination, the best 4-chamber view was selected into the memory, then 6 transverse views were displayed at different depths along the ventricle long axis, and the contour of the ventricle was drawn on each of these views. The left ventricle volume in diastole (LVDV) and the ejection fraction (EF) obtained by 3-D US were compared with those from x-ray and isotopic angiographies, and 2-D echo-time motion (2-D Echo-TM). The variations in stroke volume (SV) during a stand test, measured by 3-D US, and aortic Doppler were compared. The correlation between EF evaluated from 3-D US and x-ray or isotopic angiographies was found to be good (r = 0.80 p < 0.001; r = 0.86 p < 0.001), but lower with 2-D Echo-TM (r = 0.59 p < 0.001). For LVDV, the correlation was acceptable with x-ray angiography (r = 0.75 p < 0.001), but much lower with isotopic angiography and 2-D Echo-TM (r = 0.47 p < 0.001; r = 0.55 p < 0.001). A good correlation was also found between the SV changes measured by 3-D US and aortic Doppler (r = 0.79 p < 0.001).
Assuntos
Volume Cardíaco , Ecocardiografia Tridimensional , Cardiopatias/diagnóstico por imagem , Volume Sistólico , Idoso , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/fisiopatologia , Feminino , Cardiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Ventriculografia com Radionuclídeos , Reprodutibilidade dos Testes , Ultrassonografia DopplerRESUMO
The aim of this prospective study was to determine whether anti-carcinoembryonic antigen (anti-CEA) scintigraphy is a useful additional technique in the diagnosis recurrence of colorectal cancer. Forty patients with suspected recurrence of colorectal cancer, underwent immunoscintigraphy (IS) and helical computed tomography (CT) in the 2 weeks before surgery. Surgical findings were used to evaluate the performance of the imaging techniques. Suspected areas on IS and CT were systematically explored. Helical CT was found to be superior to IS for the liver, the sensitivity and specificity of CT being 100% and 90%, respectively, vs 53% and 100% for IS. However, IS was better than CT for the detection of extra-hepatic abdominal recurrence: sensitivity and specificity of IS were 100 and 82% respectively vs 33 and 82% for CT. Seven cases of peritoneal carcinomatosis were overlooked by helical CT. Our results indicate that IS improves detection of extra-hepatic abdominal recurrence of colorectal cancer. Immunoscintigraphy is valuable as a guide to the treatment strategy and operative procedures.
Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Adulto , Idoso , Anticorpos Monoclonais , Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/sangue , Antígeno Carcinoembrionário/imunologia , Neoplasias Colorretais/radioterapia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Radioimunodetecção/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Recidiva , Tecnécio/uso terapêutico , Distribuição Tecidual , Tomografia Computadorizada por Raios XRESUMO
This study compared prospectively the diagnostic value of dobutamine echocardiography and exercise myocardial scintigraphy for restenosis at 6 months after angioplasty of the left anterior descending artery. Forty-one patients aged 58 +/- 10 years, admitted to hospital for myocardium infarction (N = 22) or unstable angina (N = 19), with single vessel disease, were treated by angioplasty of one lesion of the left anterior descending artery after initial evaluation of the left ventricular ejection fraction by echocardiography. At 6 months, left ventricular function was reassessed by echocardiography, dobutamine echocardiography and exercise myocardial scintigraphy (Thallium 201) performed without treatment. Coronary angiography was performed at the same time and showed 8 restenosis (19.5%). Overall, in this series, dobutamine echo and scintigraphy had respectively a sensitivity of 37.5% and 75%, and a specificity of 97% and 70% (p < 0.02). Nine patients had left ventricular dysfunction unchanged compared with the initial measurement without viability in the territory of the left anterior descending artery with low dose dobutamine (group 1); thirty-two patients had improved or normal left ventricular ejection fraction with myocardial viability (group 2). In group 1, no cases of restenosis were detected by dobutamine echocardiography but_of them had myocardial scintigraphic evidence of ischaemia. In group 2, the sensitivity of the two techniques was comparable but dobutamine echo was more specific than scintigraphy (96 versus 75%, p = 0.03). In conclusion, dobutamine echocardiography may be indicated in the diagnosis of restenosis of the left anterior descending artery and in cases of viability in its territory. In its absence, myocardial scintigraphy seems to be preferable.