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1.
Sci Rep ; 13(1): 16798, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798302

RESUMO

Deaths from malaria remain staggering despite global support that drives research into new territories. One major gap is our understanding of the sexual biological aspects of the male mosquito, which maintain the vector population solidity. Although Anopheles funestus s.s. is an extremely efficient African vector, little is known about the network between its sexual physiology and gene expression. The Culicidae male's sexual maturity involves a suite of physiological changes, such as genitalia rotation that is necessary for successful mating to occur. We show that mating success is guided by genes and physiological plasticity. Transcriptome analysis between newly emerged males (immature) versus males with rotating genitalia (maturing) provides insight into possible molecular mechanisms regulating male sexual behaviour. Putative transcripts that were associated with male sexual maturation were identified and validated. The discovery of the functions of these transcripts could lead to identifying potential targets for innovative vector control interventions, and mosquito population suppression.


Assuntos
Anopheles , Malária , Animais , Masculino , Anopheles/genética , Transcriptoma , Mosquitos Vetores/genética , Perfilação da Expressão Gênica
2.
Curr Microbiol ; 78(7): 2733-2740, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34032884

RESUMO

Microalgae Dunaliella salina has been recognized as an effective source of ß-carotene. To elevate the productivity of this species, light has been served as an important induction factor, in this regard, a new idea was inspired as designing a red-to-blue wavelength shifting system based on the growth rate and cell behavior. A photobioreactor was exposed to two panels of flashing red and blue LEDs. At the commencement of the stationary phase, the wavelength shifting was applied and red LEDs were replaced with blue ones. Maximum ß-carotene content of 10 mg.g-1 was obtained; at least 300% higher than the content in the controlled system (flashing red and blue light to the end of growth).


Assuntos
Microalgas , beta Caroteno , Ciclo Celular , Proliferação de Células , Luz
3.
Int J Surg ; 46: 71-74, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28864394

RESUMO

PURPOSE: Thoracic injuries are common in both blunt and penetrating trauma. Most thoracic injuries are managed non-operatively, approximately 7-20% undergo thoracotomy. Of the injuries requiring thoracotomy, 1-6% ultimately require pulmonary resection. Wedge resection and lobectomies are well-studied in the literature; however, there is a paucity regarding reports on total pneumonectomy in the setting of trauma. Our objectives were to summarize the evidence supporting the role of trauma pneumonectomy (TP) in the current era and reiterate that despite the associated morbidity and mortality TP is justified in selective cases. METHODS: A review of the world's literature was conducted following standard guidelines. Inclusion criteria included those studies reviewing blunt and penetrating trauma to the lungs in adults (age greater than 15 year) that reported mortality rates and outcome measures. RESULTS: The PubMed search yielded 713 studies. Of these, 14 studies included pertinent information on TP. Studies included in this review were published from 1985 to 2017 and involved patient data that was collected from 1972 to 2014. Mortality ranged from 50% to 100% (median 63%; mean 68%). CONCLUSION: In the setting of severe thoracic trauma, pulmonary resection may be necessary. Less aggressive techniques are options in a stable patient; however, in the setting of ongoing hemorrhage, TP should be considered and expediently conducted. The role of damage control thoracic surgery and related techniques is vitally important in these patients to improve the significant mortality of trauma pneumonectomy.


Assuntos
Pneumonectomia/mortalidade , Traumatismos Torácicos/cirurgia , Ferimentos não Penetrantes/cirurgia , Ferimentos Penetrantes/cirurgia , Adolescente , Adulto , Feminino , Humanos , Pulmão/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
4.
Eur J Trauma Emerg Surg ; 43(6): 763-773, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28730297

RESUMO

BACKGROUND: Injuries to the ureter or bladder are relatively rare. Therefore, a high level of clinical suspicion and knowledge of operative anatomy is of utmost importance for their management. Herein, a review of the literature related to the modern diagnosis, management, and prognosis for bladder and ureteral injuries is presented. METHODS: A literature search was conducted through PubMed. A thorough search of the world's literature published in English was completed. Search terms included "injury, diagnosis, prognosis, and management for ureter and bladder". All years, both genders, as well as penetrating, blunt, and iatrogenic mechanisms were evaluated for inclusion. Following PRISMA guidelines, studies were selected based on relevance and then categorized. RESULTS: 172 potentially relevant studies were identified. Given our focus on modern diagnosis and treatment, we then narrowed the studies in each category to those published within the last 30 years, resulting in a total of 26 studies largely consisting of Level IV retrospective case series. Our review found that bladder ruptures occur from penetrating, blunt, or iatrogenic mechanisms, and most are extraperitoneal (63%). Ureteral injuries are incurred from penetrating mechanisms in 77% of cases. The overall mortality rates for bladder rupture and ureteral injury were 8 and 7%, respectively. LIMITATIONS: Limitations of this article are similar to all PRISMA-guided review articles: the dependence on previously published research and availability of references. CONCLUSION: The bladder is injured far more often than the ureter but ureteral injuries have higher injury severity. Both of these organs can be damaged by penetrating, blunt, or iatrogenic mechanisms and surgical intervention is often required for severe ureter or bladder injuries. Since symptoms of these injuries may not always be apparent, a high level of suspicion is required for appropriate diagnosis and treatment.


Assuntos
Traumatismos Abdominais/diagnóstico , Ureter/lesões , Bexiga Urinária/lesões , Traumatismos Abdominais/cirurgia , Técnicas de Apoio para a Decisão , Serviços Médicos de Emergência , Humanos
5.
Sci Rep ; 6: 27633, 2016 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-27273170

RESUMO

Ultrafast betatron x-ray emission from electron oscillations in laser wakefield acceleration (LWFA) has been widely investigated as a promising source. Betatron x-rays are usually produced via self-injected electron beams, which are not controllable and are not optimized for x-ray yields. Here, we present a new method for bright hard x-ray emission via ionization injection from the K-shell electrons of nitrogen into the accelerating bucket. A total photon yield of 8 × 10(8)/shot and 10(8 )photons with energy greater than 110 keV is obtained. The yield is 10 times higher than that achieved with self-injection mode in helium under similar laser parameters. The simulation suggests that ionization-injected electrons are quickly accelerated to the driving laser region and are subsequently driven into betatron resonance. The present scheme enables the single-stage betatron radiation from LWFA to be extended to bright γ-ray radiation, which is beyond the capability of 3(rd) generation synchrotrons.

6.
Biomed Chromatogr ; 30(7): 1036-1041, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26555197

RESUMO

During recent decades, hydrophilic interaction liquid chromatography (HILIC) ahs been introduced to fractionate or purify especially polar solutes such as peptides and proteins while reversed-phase liquid chromatography (RPLC) is also a common strategy. RPLC is also a common dimension in multidimensional chromatography. In this study, the potential of HILIC vs RPLC chromatography was compared for proteome mapping of human peripheral blood mononuclear cell extract. In HILIC a silica-based stationary phase and for RPLC a C18 column were applied. Then separated proteins were eluted to an ion trap mass spectrometry system. Our results showed that the HILIC leads to more proteins being identified in comparison to RPLC. Among the total 181 identified proteins, 56 and 38 proteins were fractionated specifically by HILIC and RPLC, respectively. In order to demonstrate this, the physicochemical properties of identified proteins such as polarity and hydrophobicity were considered. This analysis indicated that polarity may play a major role in the HILIC separation of proteins vs RPLC. Using gene ontology enrichment analysis, it was also observed that differences in physicochemical properties conform to the cellular compartment and biological features. Finally, this study highlighted the potential of HILIC and the great orthogonality of RPLC in gel-free proteomic studies. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Cromatografia de Fase Reversa/métodos , Proteômica , Humanos , Interações Hidrofóbicas e Hidrofílicas
7.
Prep Biochem Biotechnol ; 46(4): 368-75, 2016 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25844976

RESUMO

Chlorella vulgaris (C. vulgaris) microalga was investigated as a new potential feedstock for the production of biodegradable lubricant. In order to enhance microalgae lipid for biolubricant production, mixotrophic growth of C. vulgaris was optimized using statistical analysis of Plackett-Burman (P-B) and response surface methodology (RSM). A cheap substrate-based medium of molasses and corn steep liquor (CSL) was used instead of expensive mineral salts to reduce the total cost of microalgae production. The effects of molasses and CSL concentration (cheap substrates) and light intensity on the growth of microalgae and their lipid content were analyzed and modeled. Designed models by RSM showed good compatibility with a 95% confidence level when compared to the cultivation system. According to the models, optimal cultivation conditions were obtained with biomass productivity of 0.123 g L(-1) day(-1) and lipid dry weight of 0.64 g L(-1) as 35% of dry weight of C. vulgaris. The extracted microalgae lipid presented useful fatty acid for biolubricant production with viscosities of 42.00 cSt at 40°C and 8.500 cSt at 100°C, viscosity index of 185, flash point of 185°C, and pour point of -6°C. These properties showed that microalgae lipid could be used as potential feedstock for biolubricant production.


Assuntos
Lipídeos/química , Microalgas/química , Modelos Biológicos , Biomassa , Meios de Cultura , Microalgas/crescimento & desenvolvimento
8.
Prep Biochem Biotechnol ; 46(2): 150-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25807048

RESUMO

Growth of Chlorella vulgaris and its lipid production were investigated under autotrophic, heterotrophic, and mixotrophic conditions. Cheap agricultural waste molasses and corn steep liquor from industries were used as carbon and nitrogen sources, respectively. Chlorella vulgaris grew remarkably under this agricultural waste medium, which resulted in a reduction in the final cost of the biodiesel production. Maximum dry weight of 2.62 g L(-1) was obtained in mixotrophic growth with the highest lipid concentration of 0.86 g L(-1). These biomass and lipid concentrations were, respectively, 140% and 170% higher than autotrophic growth and 300% and 1200% higher than heterotrophic growth. In mixotrophic growth, independent or simultaneous occurrence of autotrophic and heterotrophic metabolisms was investigated. The growth of the microalgae was observed to take place first heterotrophically to a minimum substrate concentration with a little fraction in growth under autotrophic metabolism, and then the cells grew more autotrophically. It was found that mixotrophic growth was not a simple combination of heterotrophic and autotrophic growth.


Assuntos
Agricultura , Biotecnologia/métodos , Chlorella vulgaris/crescimento & desenvolvimento , Processos Autotróficos , Biotecnologia/instrumentação , Chlorella vulgaris/metabolismo , Chlorella vulgaris/fisiologia , Meios de Cultura , Processos Heterotróficos , Lipídeos/química , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Pigmentos Biológicos/metabolismo , Saccharum/química , Resíduos , Zea mays/química
9.
Sci Rep ; 5: 14659, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26423136

RESUMO

Ionization-induced injection mechanism was introduced in 2010 to reduce the laser intensity threshold for controllable electron trapping in laser wakefield accelerators (LWFA). However, usually it generates electron beams with continuous energy spectra. Subsequently, a dual-stage target separating the injection and acceleration processes was regarded as essential to achieve narrow energy-spread electron beams by ionization injection. Recently, we numerically proposed a self-truncation scenario of the ionization injection process based upon overshooting of the laser-focusing in plasma which can reduce the electron injection length down to a few hundred micrometers, leading to accelerated beams with extremely low energy-spread in a single-stage. Here, using 100 TW-class laser pulses we report experimental observations of this injection scenario in centimeter-long plasma leading to the generation of narrow energy-spread GeV electron beams, demonstrating its robustness and scalability. Compared with the self-injection and dual-stage schemes, the self-truncated ionization injection generates higher-quality electron beams at lower intensities and densities, and is therefore promising for practical applications.

10.
Vasa ; 36(2): 130-3, 2007 May.
Artigo em Alemão | MEDLINE | ID: mdl-17708106

RESUMO

Aneurysms of the great venous vessels represent anatomical rarities. Most malformations of the venous system published so far concern mainly the inferior vena cava and arise in different formations. Reports of malformations of the renal veins are limited to a few case reports and may lead to diagnostic and therapeutic difficulties. We report on an case of a asymptomatic, aneurysmatic venous malformation of the vena cava inferior With consideration of the entire findings we preferred a conservative treatment of the patient.


Assuntos
Aneurisma/congênito , Circulação Colateral/fisiologia , Rim/irrigação sanguínea , Veias Renais/anormalidades , Veia Cava Inferior/anormalidades , Adulto , Aneurisma/diagnóstico por imagem , Humanos , Masculino , Flebografia , Veias Renais/diagnóstico por imagem , Veia Cava Inferior/diagnóstico por imagem
11.
Eur J Vasc Endovasc Surg ; 33(5): 610-3, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17276101

RESUMO

INTRODUCTION: In the presented retrospective study, we report on our results with partial resection of infected prosthetic grafts after aorto-bifemoral graft placement in eight male and three female patients. METHODS: In all 11 patients clinical signs of infection were observed and bacteriological cultures were positive. Three patients underwent immediate surgery for perforation of an aneurysm at the distal anastomosis, eight patients underwent elective surgery. In all cases silver-coated Dacron prostheses were implanted. Assessment of outcome was based on survival, limb salvage, persistent or recurrent infection, and prosthetic graft patency. RESULTS: In two cases, a partial wound dehiscence occurred which was treated with ambulant Vacuseal dressings for 16 and 21 days until secondary wound healing was achieved. In eight patients systemic markers of inflammation completed normalised within nine days. Follow-up CT-scans failed to demonstrate any signs of recurrent infection or peri-graft fluid collections. Patients were treated with specific antibiotic therapy for no more than three months. Post-operative bacteriological cultures were negative in all patients. The mean follow-up was 2.5+/-0.5 yrs. During follow-up, none of the patients died and there were no amputations. CONCLUSION: Despite only partial resection of the infected prostheses, the reported surgical procedure offers good results. This approach maybe particularly suitable for the treatment of elderly patients with prosthesis infections.


Assuntos
Prótese Vascular/efeitos adversos , Infecções Relacionadas à Prótese/cirurgia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/epidemiologia , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Comorbidade , Desbridamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/epidemiologia , Deiscência da Ferida Operatória
12.
J Cardiovasc Surg (Torino) ; 44(6): 685-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14735028

RESUMO

AIM: The principal objective of this study was to document morphological changes in valves with acute endocarditis in order to gain further knowledge of the pathogenesis of these diseases. METHODS: Scanning and transmission electron microscopic investigations were carried out on explanted human heart valves to reveal ultrastructural changes due to bacterial endocarditis. RESULTS: Bacterial inflammation endocarditis initially induced metaplasia of the endothelial cells which then lose contact with each other. In the 2nd phase of the disease, the collagen fibres are systematically removed whereby large cavities appear. In the 3rd phase, localised hyperplasia of collagen fibres was observed often resulting in the development of vegetation. The ultrastructural changes are uniform and independent of the bacterial species. CONCLUSION: Bacterial endocarditis is therefore a set of complex interactions between endothelial cells and bacteria which should be taken into consideration for the development of new therapeutic approaches.


Assuntos
Valva Aórtica/patologia , Valva Aórtica/ultraestrutura , Valva Mitral/patologia , Valva Mitral/ultraestrutura , Adulto , Idoso , Valva Aórtica/cirurgia , Biópsia por Agulha , Técnicas de Cultura , Endocardite Bacteriana/complicações , Endocardite Bacteriana/microbiologia , Feminino , Doenças das Valvas Cardíacas/etiologia , Doenças das Valvas Cardíacas/patologia , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Estudos de Amostragem , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/microbiologia
13.
Swiss Surg ; 8(4): 165-70, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12227109

RESUMO

AIM OF STUDY: In this study, we investigated the effect of the matrix metalloproteinase inhibitor batimastat on the lung colonisation of orthotopically implanted malignant pancreatic tumor cells in SCID mice. MATERIAL AND METHODS: Following intraperitoneal anaesthesia, 10(6) Panc-TU-1 cells were orthotopically implanted in the head of the pancreas in 20 SCID mice. Seven days later, treatment of 10 of these mice with an intraperitoneal injection of batimastat (30 mg/kg body weight) was begun and continued for 14 days. Of the mice in the untreated control group, 3 were sacrificed and examined after 7 days, a further 3 after 14 days and the remainder together with the group that had been treated after 21 days. RESULTS: Tumor growth was clearly visible between the 14th. and the 21st. postoperative day. The orthotopically implanted tumor cells metastasized between the 2nd. and 3rd. postoperative week in the lung. In the control group, a diffuse metastasis of the lung was observed, but in the group of treated mice no lung metastases were found. CONCLUSION: In this mouse model, a clear reduction and inhibition of lung metastases from orthotopically implanted pancreatic tumor cells was achieved by treatment with the matrix metalloproteinase inhibitor batimastat.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/secundário , Inibidores de Metaloproteinases de Matriz , Neoplasias Pancreáticas/patologia , Fenilalanina/análogos & derivados , Fenilalanina/farmacologia , Inibidores de Proteases/farmacologia , Tiofenos/farmacologia , Animais , Avaliação de Medicamentos , Injeções Intraperitoneais , Pulmão/patologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Transplante de Neoplasias , Pâncreas/patologia , Células Tumorais Cultivadas/patologia , Células Tumorais Cultivadas/transplante
14.
Virchows Arch ; 439(1): 85-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11499845

RESUMO

To fully characterize the numerous chromosomal aberrations in two human squamous cell carcinomas (SCCs) of the lung, molecular cytogenetic characterization was carried out utilizing conventional banding analysis and multicolor fluorescence in situ hybridization (mFISH), providing simultaneous color discrimination of all 24 human chromosomes. Both tumors displayed complex aneuploid karyotypes with a host of numerical and structural chromosome abnormalities. Structural aberrations common to both SCCs included rearrangements of chromosomes 1, 3p, 7q, and 8q, contributing to net loss of chromosomal sequences on 1p, 3p, and 8p, and a net gain of 8q. The recently introduced mFISH technique enabled the disclosure of cryptic translocations and the chromosomal composition of previously unrecognized marker chromosomes. Furthermore, mFISH greatly enhanced the ability to delineate chromosomal breakpoints when integrating banding information from conventional banding analysis. Eventually, the application of mFISH as a powerful approach to refine complex tumor karyotypes is expected to result in a more detailed and complete picture of cytogenetic events associated with the development and progression of solid tumors.


Assuntos
Carcinoma de Células Escamosas/genética , Aberrações Cromossômicas , Coloração Cromossômica , Neoplasias Pulmonares/genética , Aneuploidia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Bandeamento Cromossômico , Fragilidade Cromossômica , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino
15.
Dtsch Med Wochenschr ; 126(7): 168-71, 2001 Feb 16.
Artigo em Alemão | MEDLINE | ID: mdl-11236523

RESUMO

HISTORY AND ADMISSION FINDINGS: A 21-year-old woman with known endocardial fibroelastosis diagnosed when aged 3 months was admitted because of progressive dyspnoea. The physical examination revealed symptoms of heart failure, with pulmonary rales, mild hepatomegaly, and tachyarrhythmia. INVESTIGATIONS: The electrocardiogram showed atrial fibrillation, complete right bundle branch block and right ventricular hypertrophy. Echocardiography indicated hypertrophy and dilatation of the right ventricle (61 mm) with tricuspid regurgitation and hypoplasia of the left ventricle. Heart catheterization confirmed pulmonary hypertension (60/46 mmHg) as well as dilatation and hypokinesia of the right ventricle. Right ventricular biopsy showed severe myocardial hypertrophy resulting from secondary pulmonary hypertension, while no evidence of myocarditis or idiopathic dilated cardiomyopathy was found. TREATMENT AND COURSE: Symptoms of heart failure improved under medical treatment with digitalis, angiotensin-converting enzyme inhibitor and diuretics. CONCLUSION: Primary endocardial fibroelastosis of the contracted type must be included in the differential diagnosis of heart failure occurring in young adults.


Assuntos
Fibroelastose Endocárdica/complicações , Fibroelastose Endocárdica/diagnóstico , Insuficiência Cardíaca/etiologia , Adulto , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Fibrilação Atrial/complicações , Cateterismo Cardíaco , Diagnóstico Diferencial , Digitalis/uso terapêutico , Diuréticos/uso terapêutico , Dispneia , Ecocardiografia , Eletrocardiografia , Fibroelastose Endocárdica/fisiopatologia , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Fitoterapia , Plantas Medicinais , Plantas Tóxicas
16.
J Heart Valve Dis ; 9(4): 576-82, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10947053

RESUMO

BACKGROUND AND AIM OF THE STUDY: In recent years a number of fixation and anti-calcification methods have been developed, but little is yet known about the calcification process of biological valves. The aims of this study were to: (i) perform a systematic ultrastructural investigation on various biological valves; and (ii) determine the extent of calcification of these valves in a subcutaneous rat model. METHODS: The following porcine aortic prostheses were investigated: Toronto-SPV, Intact, Freestyle, Mosaic and Hancock-II. Samples taken from the valve leaflets, and in the case of the Freestyle and Toronto-SPV valves also from the aortic wall, were examined ultrastructurally using scanning and transmission electron microscopy. Other samples were implanted subcutaneously in Wistar rats for 12 weeks. The calcium content of the samples was measured using atomic absorption spectrophotometry. RESULTS: All valves examined showed a considerable loss of the endothelial cover. Significant changes in valve ultrastructure were also detected. With regard to calcium content, two valve groups could be distinguished (p <0.05): (i) those with high calcium content, e.g. Toronto-SPV and Intact (>40 mg/g dry tissue); and (ii) those with low calcium content, e.g. Mosaic, Freestyle and Hancock-II (<5 mg/g). CONCLUSION: Fixation methods have pronounced effects on the ultrastructural integrity of bioprostheses. The degenerative calcification of bioprostheses can be effectively inhibited by glutaraldehyde-free fixation and anti-calcification treatments.


Assuntos
Valva Aórtica/ultraestrutura , Bioprótese , Calcinose/patologia , Próteses Valvulares Cardíacas , Animais , Calcinose/prevenção & controle , Cálcio/análise , Feminino , Implante de Prótese de Valva Cardíaca , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Desenho de Prótese , Ratos , Ratos Wistar , Suínos
17.
Scand Cardiovasc J ; 34(6): 589-92, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11214013

RESUMO

OBJECTIVE: Immunological effects have been addressed as key factors for the long-term results of biological porcine aortic prostheses. In this study we investigated the influence of glutaraldehyde fixation on the expression of SLA (swine leucocyte antigens) and the calcification of porcine cardiac tissue. DESIGN: Deparaffinized sections obtained from porcine aortic tissue were fixed in a buffered glutaraldehyde solution for 1, 2, 3, 24 and 72 hours, respectively, and finally immunostained with monoclonal anti-SLA class I antibody 2.27-3a and anti-SLA-II antibody MSA3. Sixteen samples from fixed porcine cardiac tissue and, for comparison, 8 samples from leaflets of Toronto-SPV and Freestyle valves were implanted subcutaneously in 10 Wistar rats for 12 weeks and their calcium content was measured by atomic absorption spectrophotometry. RESULTS: SLA-I epitopes were no longer detectable using anti-SLA-I antibodies after fixation for 3 h. The SLA-II antigens remained detectable after longer fixation period. Short-time fixation resulted in marked calcification of the porcine cardiac tissue and to destruction of the SLA-I epitopes, whereas, even after longer fixation time, the epitopes of the SLA-II antigen remain unaffected. CONCLUSION: Chelate formation due to glutaraldehyde treatment provides protection against calcification. Short-time fixed porcine cardiac tissue has a tendency towards a greater degree of calcification than longer fixation periods. Based on the present results, it is pointless to set the length of fixation to switch off the immunogenicity.


Assuntos
Bioprótese , Calcinose/imunologia , Cardiomiopatias/imunologia , Glutaral , Próteses Valvulares Cardíacas , Antígenos de Histocompatibilidade Classe II/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Animais , Feminino , Imuno-Histoquímica , Modelos Animais , Ratos , Ratos Wistar , Suínos
18.
Vasa ; 28(4): 293-5, 1999 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-10611849

RESUMO

Deep phlebothromboses of iliacal vein and aplasia of the inferior vena cava Coincidence of deep phlebothromboses of iliacal vein and aplasia of the inferior vena cava is a rare condition but has significance for further therapy. Two cases of this anatomical malformation with complications are presented and the importance of therapeutical strategies are discussed. We report on our experiences with the operative procedures of venous thrombectomy and arteriovenous fistula, aimed at increasing the venous flow in the collaterals of the aplastic inferior vena cava.


Assuntos
Veia Safena/anormalidades , Tromboflebite/etiologia , Adulto , Derivação Arteriovenosa Cirúrgica , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Flebografia , Veia Safena/diagnóstico por imagem , Trombectomia , Tromboflebite/diagnóstico por imagem , Tromboflebite/cirurgia , Tomografia Computadorizada por Raios X
19.
Cardiovasc Surg ; 7(7): 735-41, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10639049

RESUMO

The present study aimed at investigating the influence of fixation methods on the ultrastructure and calcium content of five different aortic biovalves. Biovalves subcutaneously implanted in Wistar rats for 12 weeks demonstrated significant differences in their calcium contents. Using Scheffe tests, two different groups of biovalves could be distinguished: (i) valves with high calcium content, such as Toronto-SPV (165 +/- 42 mg/g dry tissue) and Intact (193 +/- 36 mg/g dry tissue), and (ii) valves with low calcium content, such as Mosaic (2.7 +/- 1.8 mg/g dry tissue), Freestyle (2.3 +/- 1.1 mg/g dry tissue) and Hancock-II (3.6 +/- 1.2 mg/g dry tissue) (P < 0.05). All biovalves with an ultrastructurally preserved endothelium exhibited a low calcification tendency. The data suggest that if the endothelium is lost as a result of the fixation procedure, then calcification can only be prevented by appropriate anticalcification methods.


Assuntos
Valva Aórtica/ultraestrutura , Bioprótese , Calcinose/patologia , Próteses Valvulares Cardíacas , Falha de Prótese , Animais , Valva Aórtica/metabolismo , Calcinose/metabolismo , Calcinose/prevenção & controle , Cálcio/metabolismo , Modelos Animais de Doenças , Feminino , Microscopia Eletrônica de Varredura , Ratos , Ratos Wistar , Preservação de Tecido
20.
APMIS ; 106(10): 935-40, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9833694

RESUMO

In this study we have used monoclonal antibodies directed against antigens of the major histocompatibility complex (MHC) class I and class II to reveal the detailed cellular distribution of swine lymphocyte alloantigens (SLA) in cardiac tissue. By applying a sensitive immunophosphatase staining reaction we detected the ubiquitous expression of SLA class I and class II on the vascular endothelium. Endothelial cells of capillaries and blood vessels were intensely stained structures in the examined swine hearts. Similar staining patterns were observed in control experiments with anti-von Willebrand factor serum and Dolichus biflorus lectin used as immunohistochemical markers for endothelial cells. The luminal layer of studied pulmonary valves exhibited a strong staining reaction with anti-SLA class I and class II antibodies. In contrast, normal cardiac myocytes failed to express immunodetectable amounts of either of the SLA determinants. Intercalated discs in porcine heart tissue did not react with either anti-SLA class I or class II antibodies. Our data showing the abundant expression of SLA molecules on endothelial cells in normal swine heart may have physiological implications in cell-mediated rejection occurring in xenotransplanted hearts.


Assuntos
Antígenos de Histocompatibilidade Classe II/biossíntese , Antígenos de Histocompatibilidade Classe I/biossíntese , Miocárdio/metabolismo , Animais , Imuno-Histoquímica , Miocárdio/química , Miocárdio/imunologia , Suínos
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