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1.
ACS Appl Mater Interfaces ; 15(40): 46933-46940, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782757

RESUMO

The transfer of photogenerated charges through interfaces in heterojunction photoanodes is a key process that controls the efficiency of solar water splitting. Considering Co3O4/SiOx/Si photoanodes prepared by physical vapor deposition as a representative case study, it is shown that defects normally present in the native SiOx layer dramatically affect the onset of the photocurrent. Electron paramagnetic resonance indicates that the signal of defects located in dangling bonds of trivalent Si atoms at the Si/SiOx interface vanishes upon vacuum annealing at 850 °C. Correspondingly, the photovoltage of the photoanode increases to ≈500 mV. Similar results are obtained for NiO/SiOx/Si photoanodes. Photoelectrochemical analysis and impedance spectroscopy (in solution and in the solid state) indicate how the defect annealing modifies the Co3O4/SiOx/Si junction. This work shows that defect annealing at the solid-solid interface in composite photoanodes strongly improves the efficiency of charge transfer through interfaces, which is the basis for effective solar-to-chemical energy conversion.

2.
Hum Reprod ; 38(4): 762-775, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36824049

RESUMO

STUDY QUESTION: Can chromosomal abnormalities beyond copy-number aneuploidies (i.e. ploidy level and microdeletions (MDs)) be detected using a preimplantation genetic testing (PGT) platform? SUMMARY ANSWER: The proposed integrated approach accurately assesses ploidy level and the most common pathogenic microdeletions causative of genomic disorders, expanding the clinical utility of PGT. WHAT IS KNOWN ALREADY: Standard methodologies employed in preimplantation genetic testing for aneuploidy (PGT-A) identify chromosomal aneuploidies but cannot determine ploidy level nor the presence of recurrent pathogenic MDs responsible for genomic disorders. Transferring embryos carrying these abnormalities can result in miscarriage, molar pregnancy, and intellectual disabilities and developmental delay in offspring. The development of a testing strategy that integrates their assessment can resolve current limitations and add valuable information regarding the genetic constitution of embryos, which is not evaluated in PGT providing new level of clinical utility and valuable knowledge for further understanding of the genomic causes of implantation failure and early pregnancy loss. To the best of our knowledge, MDs have never been studied in preimplantation human embryos up to date. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort analysis including blastocyst biopsies collected between February 2018 and November 2021 at multiple collaborating IVF clinics from prospective parents of European ancestry below the age of 45, using autologous gametes and undergoing ICSI for all oocytes. Ploidy level determination was validated using 164 embryonic samples of known ploidy status (147 diploids, 9 triploids, and 8 haploids). Detection of nine common MD syndromes (-4p=Wolf-Hirschhorn, -8q=Langer-Giedion, -1p=1p36 deletion, -22q=DiGeorge, -5p=Cri-du-Chat, -15q=Prader-Willi/Angelman, -11q=Jacobsen, -17p=Smith-Magenis) was developed and tested using 28 positive controls and 97 negative controls. Later, the methodology was blindly applied in the analysis of: (i) 100 two pronuclei (2PN)-derived blastocysts that were previously defined as uniformly euploid by standard PGT-A; (ii) 99 euploid embryos whose transfer resulted in pregnancy loss. PARTICIPANTS/MATERIALS, SETTING, METHODS: The methodology is based on targeted next-generation sequencing of selected polymorphisms across the genome and enriched within critical regions of included MD syndromes. Sequencing data (i.e. allelic frequencies) were analyzed by a probabilistic model which estimated the likelihood of ploidy level and MD presence, accounting for both sequencing noise and population genetics patterns (i.e. linkage disequilibrium, LD, correlations) observed in 2504 whole-genome sequencing data from the 1000 Genome Project database. Analysis of phased parental haplotypes obtained by single-nucleotide polymorphism (SNP)-array genotyping was performed to confirm the presence of MD. MAIN RESULTS AND THE ROLE OF CHANCE: In the analytical validation phase, this strategy showed extremely high accuracy both in ploidy classification (100%, CI: 98.1-100%) and in the identification of six out of eight MDs (99.2%, CI: 98.5-99.8%). To improve MD detection based on loss of heterozygosity (LOH), common haploblocks were analyzed based on haplotype frequency and LOH occurrence in a reference population, thus developing two further mathematical models. As a result, chr1p36 and chr4p16.3 regions were excluded from MD identification due to their poor reliability, whilst a clinical workflow which incorporated parental DNA information was developed to enhance the identification of MDs. During the clinical application phase, one case of triploidy was detected among 2PN-derived blastocysts (i) and one pathogenic MD (-22q11.21) was retrospectively identified among the biopsy specimens of transferred embryos that resulted in miscarriage (ii). For the latter case, family-based analysis revealed the same MD in different sibling embryos (n = 2/5) from non-carrier parents, suggesting the presence of germline mosaicism in the female partner. When embryos are selected for transfer based on their genetic constitution, this strategy can identify embryos with ploidy abnormalities and/or MDs beyond aneuploidies, with an estimated incidence of 1.5% (n = 3/202, 95% CI: 0.5-4.5%) among euploid embryos. LIMITATIONS, REASONS FOR CAUTION: Epidemiological studies will be required to accurately assess the incidence of ploidy alterations and MDs in preimplantation embryos and particularly in euploid miscarriages. Despite the high accuracy of the assay developed, the use of parental DNA to support diagnostic calling can further increase the precision of the assay. WIDER IMPLICATIONS OF THE FINDINGS: This novel assay significantly expands the clinical utility of PGT-A by integrating the most common pathogenic MDs (both de novo and inherited ones) responsible for genomic disorders, which are usually evaluated at a later stage through invasive prenatal testing. From a basic research standpoint, this approach will help to elucidate fundamental biological and clinical questions related to the genetics of implantation failure and pregnancy loss of otherwise euploid embryos. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. S.C., M.F., F.C., P.Z., I.P., L.G., C.P., M.P., D.B., J.J.-A., D.B.-J., J.M.-V., and C.R. are employees of Igenomix and C.S. is the head of the scientific board of Igenomix. A.C. and L.P. are employees of JUNO GENETICS. Igenomix and JUNO GENETICS are companies providing reproductive genetic services. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Aborto Espontâneo , Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Diagnóstico Pré-Implantação/métodos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Aborto Espontâneo/patologia , Estudos Prospectivos , Testes Genéticos/métodos , Blastocisto/patologia , Aneuploidia
3.
Hum Reprod ; 36(7): 2050-2061, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34021342

RESUMO

STUDY QUESTION: What is the clinical validity and utility of preconception Expanded Carrier Screening (ECS) application on the management of prospective parents? SUMMARY ANSWER: The high detection rate of at-risk couples (ARCs) and the high proportion opting for IVF/preimplantation genetic testing (PGT) treatment demonstrate the clinical utility of ECS in the preconception space in IVF and general population. WHAT IS KNOWN ALREADY: About 2-4% of couples are at risk of conceiving a child with an autosomal recessive or X-linked genetic disorder. In recent years, the increasing cost-effectiveness of genetic diagnostic techniques has allowed the creation of ECS panels for the simultaneous detection of multiple recessive disorders. Comprehensive preconception genetic screening holds the potential to significantly improve couple's genetic risk assessment and reproductive planning to avoid detectable inheritable genetic offspring. STUDY DESIGN, SIZE, DURATION: A total of 3877 individuals without a family history of genetic conditions were analyzed between January 2017 and January 2020. Of the enrolled individuals, 1212 were gamete donors and 2665 were patients planning on conceiving from both the IVF and the natural conception group. From the non-donor cohort, 1133 were analyzed as individual patients, while the remaining ones were analyzed as couples, for a total of 766 couples. PARTICIPANTS/MATERIALS, SETTING, METHODS: A focused ECS panel was developed following American College of Obstetrics and Gynecology ACOG-recommended criteria (prevalence, carrier rate, severity), including highly penetrant severe childhood conditions. Couples were defined at-risk when both partners carried an autosomal recessive pathogenic/likely pathogenic variant (PLP) on the same gene or when the woman was a carrier of an X-linked PLP variant. ARC detection rate defined the clinical validity of the ECS approach. Clinical utility was evaluated by monitoring ARCs reproductive decision making. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 402 individuals (10.4%) showed PLP for at least one of the genes tested. Among the 766 couples tested, 173 showed one carrier partner (22.6%), whereas 20 couples (2.6%) were found to be at increased risk. Interestingly, one ARC was identified as a result of cascade testing in the extended family of an individual carrying a pathogenic variant on the Survival Of Motor Neuron 1SMN1 gene. Of the identified ARCs, 5 (0.7%) were at risk for cystic fibrosis, 5 (0.7%) for fragile X syndrome, 4 (0.5%) for spinal muscular atrophy, 4 (0.5%) for Beta-Thalassemia/Sickle Cell Anemia, 1 (0.1%) for Smith-Lemli-Opitz Syndrome and 1 (0.1%) for Duchenne/Becker Dystrophy. Fifteen ARCs were successfully followed up from both the IVF and the natural conception groups. All of these (15/15) modified their reproductive planning by undergoing ART with Preimplantation Genetic Testing for Monogenic disease and Aneuploidies (PGT-M and PGT-A). To date, 6/15 (40%) couples completed their PGT cycle with euploid/unaffected embryos achieving a pregnancy after embryo transfer and three of them have already had an unaffected baby. LIMITATIONS, REASONS FOR CAUTION: The use of a limited panel of core gene-disease pairs represents a limitation on the research perspective as it can underestimate the rate of detectable carriers and ARCs in this cohort of prospective parents. Expanding the scope of ECS to a larger panel of conditions is becoming increasingly feasible, thanks to a persistent technological evolution and progressive cataloging of gene-disease associations. WIDER IMPLICATIONS OF THE FINDINGS: These results highlight the potential clinical validity and utility of ECS in reducing the risk of a pregnancy affected by a detectable inheritable genetic condition. The steady reduction in the costs of genetic analyses enables the expansion of monogenic testing/screening applications at the preimplantation stage, thus, providing valid decisional support and reproductive autonomy to patients, particularly in the context of IVF. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. A.C., M.F., S.C., M.P., L.G., and C.P. are employees of Igenomix Italy. C.S. is the head of the scientific board of Igenomix. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Transferência Embrionária , Diagnóstico Pré-Implantação , Criança , Feminino , Fertilização in vitro , Triagem de Portadores Genéticos , Testes Genéticos , Humanos , Itália , Gravidez , Estudos Prospectivos
4.
Br J Anaesth ; 120(5): 904-913, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29661408

RESUMO

BACKGROUND: Cerebrospinal-fluid (CSF) drainage is recommended by current guidelines for spinal protection during open and endovascular repairs of thoracic and thoraco-abdominal aortic aneurysms. In the published literature, great variability exists in the rate of CSF-related complications and morbidity. Herein, we perform a systematic review and meta-analysis on the incidence of CSF drainage-related complications, and compare the complication rates between open and endovascular repairs. METHODS: The systematic review was conducted according to the Meta-Analysis of Observational Studies in Epidemiology guidelines. Thirty-four studies (4714 patients) were included in the quantitative analysis. The CSF drainage-related complications were categorised as mild, moderate, and severe. Pooled event rates for each complication category were estimated using a random-effect model. Random-effect uni- and multivariable meta-regression analyses were used to assess the effect of aortic-repair approach (open vs endovascular) and the CSF drainage criteria on CSF drainage-related complications. RESULTS: The pooled event rates were 6.5% [95% confidence interval (CI): 4.3-9.8%] for overall complications, 2% (95% CI: 1.1-3.4%) for minor complications, 3.7% (95% CI: 2.5-5.6%) for moderate complications, and 2.5% (95% CI: 1.6-3.8%) for severe complications. The drainage-related-mortality pooled event rate was 0.9% (95% CI: 0.6-1.4%). The uni- and multivariable meta-regression analyses showed no difference in complication rates between the open and endovascular approaches, or between the different CSF drainage protocols. CONCLUSION: The complication rate for CSF drainage is not negligible. Our results help define a more accurate risk-benefit ratio for CSF drain placement at the time of repair of thoracic and thoraco-abdominal aneurysms.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Drenagem/métodos , Procedimentos Endovasculares/métodos , Complicações Pós-Operatórias/líquido cefalorraquidiano , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/líquido cefalorraquidiano , Humanos , Resultado do Tratamento
5.
Biofabrication ; 4(3): 035005, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22914604

RESUMO

The aortic valve exhibits complex three-dimensional (3D) anatomy and heterogeneity essential for the long-term efficient biomechanical function. These are, however, challenging to mimic in de novo engineered living tissue valve strategies. We present a novel simultaneous 3D printing/photocrosslinking technique for rapidly engineering complex, heterogeneous aortic valve scaffolds. Native anatomic and axisymmetric aortic valve geometries (root wall and tri-leaflets) with 12-22 mm inner diameters (ID) were 3D printed with poly-ethylene glycol-diacrylate (PEG-DA) hydrogels (700 or 8000 MW) supplemented with alginate. 3D printing geometric accuracy was quantified and compared using Micro-CT. Porcine aortic valve interstitial cells (PAVIC) seeded scaffolds were cultured for up to 21 days. Results showed that blended PEG-DA scaffolds could achieve over tenfold range in elastic modulus (5.3±0.9 to 74.6±1.5 kPa). 3D printing times for valve conduits with mechanically contrasting hydrogels were optimized to 14 to 45 min, increasing linearly with conduit diameter. Larger printed valves had greater shape fidelity (93.3±2.6, 85.1±2.0 and 73.3±5.2% for 22, 17 and 12 mm ID porcine valves; 89.1±4.0, 84.1±5.6 and 66.6±5.2% for simplified valves). PAVIC seeded scaffolds maintained near 100% viability over 21 days. These results demonstrate that 3D hydrogel printing with controlled photocrosslinking can rapidly fabricate anatomical heterogeneous valve conduits that support cell engraftment.


Assuntos
Valva Aórtica/anatomia & histologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Alicerces Teciduais/veterinária , Alginatos/química , Animais , Valva Aórtica/citologia , Materiais Biocompatíveis/química , Sobrevivência Celular , Células Cultivadas , Módulo de Elasticidade , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Polietilenoglicóis/química , Suínos , Engenharia Tecidual
6.
Transplant Proc ; 43(4): 1098-102, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21620062

RESUMO

UNLABELLED: Assessing adequate volemia to avoid fluid overload and pulmonary edema perioperatively in liver transplantation (LT) is a challenge both for the anesthetist and the intensivist. Volumetric preload indices, such as intrathoracic blood volume index (ITBVI), measured by transpulmonary thermodilution, and continuous end-diastolic volume index (EDVI), measured by pulmonary artery thermodilution, were shown to better reflect preload than central venous pressure (CVP) or pulmonary artery occlusion pressure (PAOP). An ITBVI increase soon after the graft reperfusion influenced pulmonary perfusion without an alteration of extravascular lung water index (EVLWI) and without impaired oxygenation. This study was designed to evaluate relationships between CVP, PAOP, ITBVI, EDVI, and stroke volume index (SVI) within 48 hours after LT. We also investigated the relationship between EVLWI and arterial partial pressure of oxygen and inspired oxygen fraction ratio (PaO(2)/FiO(2)). METHODS: We enrolled 125 patients (103 men and 22 women) undergoing LT. All patients were monitored with the PiCCO system (Pulsion Medical System) and with advanced pulmonary artery catheter connected to the Vigilance System. Hemodynamic-volumetric data were collected upon intensive care unit admission and every 8 hours up to 48 hours. Univariate and multivariate regression models were fitted to assess associations between SVI and EDVI, ITBVI, and filling pressures after adjusting for the right ventricular ejection fraction (RVEF, categorized as ≤30, 31-40, or >40) and the phase of the observation period. We also assessed associations between PaO(2)/FiO(2) and EVLWI. RESULTS: SVI was associated with EDVI, ITBVI, and RVEF. The models showing the best fit to the data were those including EDVI and ITBVI. Neither CVP nor PAOP showed correlation with SVI. EVLWI inversely correlated with PaO(2)/FiO(2). CONCLUSIONS: In the first 48 hours after LT, ITBVI and EDVI were associated with SVI assessment, whereas CVP and PAOP were not related. EVLWI significantly inversely correlated with PaO(2)/FiO(2).


Assuntos
Volume Sanguíneo , Água Extravascular Pulmonar , Hidratação/efeitos adversos , Hipovolemia/terapia , Transplante de Fígado/efeitos adversos , Monitorização Intraoperatória , Monitorização Fisiológica , Edema Pulmonar/prevenção & controle , Adulto , Idoso , Pressão Sanguínea , Cateterismo de Swan-Ganz , Pressão Venosa Central , Cuidados Críticos , Feminino , Humanos , Hipovolemia/diagnóstico , Hipovolemia/etiologia , Hipovolemia/fisiopatologia , Itália , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Monitorização Fisiológica/métodos , Oxigênio/sangue , Pressão Parcial , Valor Preditivo dos Testes , Artéria Pulmonar/fisiopatologia , Edema Pulmonar/diagnóstico , Edema Pulmonar/etiologia , Edema Pulmonar/fisiopatologia , Volume Sistólico , Termodiluição , Fatores de Tempo , Resultado do Tratamento
7.
Science ; 332(6026): 213-6, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21474754

RESUMO

In addition to its search for extrasolar planets, the NASA Kepler mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solar-type stars in the Kepler field of view, an ensemble that is large enough to allow statistical studies of intrinsic stellar properties (such as mass, radius, and age) and to test theories of stellar evolution. We find that the distribution of observed masses of these stars shows intriguing differences to predictions from models of synthetic stellar populations in the Galaxy.

8.
J Chemother ; 20(4): 497-502, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18676232

RESUMO

Gastric cancer remains a major health problem despite its decline in incidence in Western countries. Although radical surgery represents the primary curative option for gastric cancer patients, most of them relapse and die due to their disease despite an R0 resection. At present the routine use of postoperative adjuvant therapy to reduce disease recurrence is still considered an investigational approach. Out of a total of 275 patients (stage IB through IV M0 AJCC/UICC) who underwent surgery for gastric cancer at our Surgery Unit between 1993 and 2001, 156 were eligible for adjuvant chemotherapy, of whom only 52 accepted to undergo this treatment. This group of patients was retrospectively compared with a control group (1:2) and overall survival was assessed using hazard ratio and Kaplan-Meier estimates. Five-year survival was 40% in the chemotherapy group and 37.8% in the group which underwent surgery alone. Indeed, chemotherapy did not reduce the risk of death (HR 0.87, 95% CI = 0.57-1.34, p=0.54). Serosal involvement and the invasion of more than 6 lymph nodes were the main independent prognostic factors identified by multivariate analysis. The current study did not show a clear advantage of chemotherapy over surgery alone. However, our results can help to define strategies for future clinical trials with the use of new regimens based on more effective and less toxic drugs.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Análise de Sobrevida
9.
Pharmazie ; 61(8): 670-2, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16964707

RESUMO

This paper describes the preparation of chitosan modified with dialdehydes, glutaraldehyde (CH-Glu) and glyoxal (CH-Gly) and its application in the isolation of the flavonoids swertisin and 2"-O-rhamnosylswertisin from A. mollucana. The additional non-polar alkyl groups increase the hydrophobicity of the sorbent. The results show that the separation was mediated by hydrophobic interaction (CH-Glu), as well as hydrogen bonding, between phenolic OH or rhamnosil residues from the flavonoids, and the free amine groups (CH-Gly).


Assuntos
Aleurites/química , Quitosana/química , Flavonoides/química , Glutaral/química , Glioxal/química , Sequência de Carboidratos , Fenômenos Químicos , Físico-Química , Flavonoides/isolamento & purificação , Ligação de Hidrogênio , Dados de Sequência Molecular
10.
Klin Padiatr ; 216(2): 87-90, 2004.
Artigo em Alemão | MEDLINE | ID: mdl-15106081

RESUMO

Cow's milk allergy is the most common type of food allergy in infants. Most infants develop symptoms one week after initiating the feeding of cow's milk based formulas though sensitisation in utero and via mother's milk are also possible. We report on three newborns who received whey baths after birth and developed allergic skin reactions. Cow's milk allergy was diagnosed. In our opinion the whey baths could be responsible for the sensitisation via skin and the allergic skin reactions. The risks and benefits of whey baths for newborns and infants should therefore be carefully considered.


Assuntos
Dermatite Alérgica de Contato/etiologia , Dermatite Atópica/etiologia , Hipersensibilidade a Leite/etiologia , Proteínas do Leite/efeitos adversos , Animais , Banhos , Bovinos , Dermatite Alérgica de Contato/imunologia , Dermatite Atópica/imunologia , Diagnóstico Diferencial , Feminino , Humanos , Hipersensibilidade Imediata/etiologia , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/sangue , Lactente , Recém-Nascido , Testes Intradérmicos , Masculino , Hipersensibilidade a Leite/imunologia , Proteínas do Leite/imunologia , Leite Humano/imunologia , Gravidez , Teste de Radioalergoadsorção , Fatores de Risco , Urticária/etiologia , Urticária/imunologia , Proteínas do Soro do Leite
11.
Pharmazie ; 58(9): 629-30, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14531457

RESUMO

This paper describes the preparation, characterization and use of a derivative of chitosan as a chromatographic sorbent. Chitosan modified with benzenic ring (CH-Bz) was used to separate two flavonoids, swertisin and 2"-O-rhamnosylswertisin, from ethyl acetate fraction of Aleurites moluccana. The results showed that CH-Bz can be used as a sorbent for the separation of flavonoid compounds. The studies showed that CH-Bz in column chromatography produces goods results, separation of the flavonoid compounds.


Assuntos
Aleurites/química , Benzaldeídos/química , Quitina/análogos & derivados , Quitina/química , Flavonoides/isolamento & purificação , Acetatos , Brasil , Quitosana , Cromatografia Líquida , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Extratos Vegetais , Solventes , Espectrofotometria Infravermelho
12.
Circ Res ; 88(2): 167-74, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11157668

RESUMO

Bone marrow (BM)-derived circulating endothelial precursor cells (CEPs) are thought to play a role in postnatal angiogenesis. Emerging evidence suggests that angiogenic stress of vascular trauma may induce mobilization of CEPs to the peripheral circulation. In this regard, we studied the kinetics of CEP mobilization in two groups of patients who experienced acute vascular insult secondary to burns or coronary artery bypass grafting (CABG). In both burn and CABG patients, there was a consistent, rapid increase in the number of CEPs, determined by their surface expression pattern of vascular endothelial growth factor receptor 2 (VEGFR2), vascular endothelial cadherin (VE-cadherin), and AC133. Within the first 6 to 12 hours after injury, the percentage of CEPs in the peripheral blood of burn or CABG patients increased almost 50-fold, returning to basal levels within 48 to 72 hours. Mobilized cells also formed late-outgrowth endothelial colonies (CFU-ECs) in culture, indicating that a small, but significant, number of circulating endothelial cells were BM-derived CEPs. In parallel to the mobilization of CEPs, there was also a rapid elevation of VEGF plasma levels. Maximum VEGF levels were detected within 6 to 12 hours of vascular trauma and decreased to baseline levels after 48 to 72 hours. Acute elevation of VEGF in the mice plasma resulted in a similar kinetics of mobilization of VEGFR2(+) cells. On the basis of these results, we propose that vascular trauma may induce release of chemokines, such as VEGF, that promotes rapid mobilization of CEPs to the peripheral circulation. Strategies to improve the mobilization and incorporation of CEPs may contribute to the acceleration of vascularization of the injured vascular tissue.


Assuntos
Vasos Sanguíneos/metabolismo , Endotélio Vascular/metabolismo , Glicoproteínas/metabolismo , Peptídeos/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Células-Tronco/metabolismo , Antígeno AC133 , Animais , Antígenos CD , Queimaduras/sangue , Caderinas/genética , Caderinas/metabolismo , Contagem de Células , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Ponte de Artéria Coronária , Fatores de Crescimento Endotelial/sangue , Endotélio Vascular/citologia , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Antígenos CD15/metabolismo , Linfocinas/sangue , Antígeno de Macrófago 1/metabolismo , Camundongos , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores de Fatores de Crescimento/genética , Receptores de Fatores de Crescimento do Endotélio Vascular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/citologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Fator de von Willebrand/metabolismo
13.
Artif Organs ; 24(7): 507-13, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10916060

RESUMO

Activated clotting time (ACT) is the most commonly used laboratory test to control the heparin effect during extracorporeal techniques. The study was undertaken in order to test in vitro the influence of heparin, platelet count, hematocrit, platelet fragmentation, and platelet activation on ACT. Blood was drawn from volunteer donors into syringes containing citrate. Platelet counts and hematocrit were modified. Platelets were fragmented by sonifier or activated by collagen and adenosine diphosphate (ADP). Different heparin final concentrations were created. Increasing concentrations of heparin had a significant effect on ACT. However, it was not predictable in every case in concentrations lower than 1.0 U/ml. Platelet count generally had no significant effect on ACT. The effect of hematocrit was detectable in a group but not in single cases. Fragmented platelets significantly shortened ACT only without addition of heparin, and the effect was only partly predictable. Activation of platelets by collagen and ADP induced no significant changes. Our results show that heparin is reflected by ACT but that effect is not predictable in every specific patient. Our results also show that other variables that may be altered during extracorporeal techniques such as platelet count, hematocrit, activation, and fragmentation of platelets do not severely influence the ACT.


Assuntos
Plaquetas/fisiologia , Hematócrito , Heparina/farmacologia , Tempo de Coagulação do Sangue Total , Difosfato de Adenosina/farmacologia , Análise de Variância , Colágeno/farmacologia , Humanos , Técnicas In Vitro , Modelos Lineares , Contagem de Plaquetas , Estatísticas não Paramétricas , Ultrassom
14.
Perfusion ; 15(3): 231-6, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10866425

RESUMO

Challenges related to perfusion support of thoracoabdominal aneurysm repair include maintenance of distal aortic perfusion, rapidity of fluid resuscitation, and avoidance of both hypothermia and excessive hemodilution. Using available technology, we have devised a circuit and protocol that addresses these issues. To accomplish such support a bypass circuit consisting of 3/8 inch tubing connected to a centrifugal pump and low-prime heat exchanger was constructed. The circuit was primed via 1/4 inch spiked connectors attached to a 3-liter bag of normal saline. After initial de-airing, the solution was recirculated through this bag. Patients were anticoagulated with 1 mg/kg of heparin prior to initiation of support. Left atrial-descending aorta bypass was used primarily. A cell salvage device was used for autotransfusion. All blood products were delivered via a rapid infusion device. During partial exsanguination, shed blood was not processed, but directed to the rapid infusor for immediate retransfusion. Any packed cells given were washed prior to transfusion. Citrate dextrose solution was used as an anticoagulant for the cell scavenger. This configuration was used successfully in 50 procedures during an 18-month period. Use of this low-prime, custom circuit reduced both hemodilution and cost. A connection off the cell salvage pump offers fast retransfusion of shed blood during partial exsanguination. Minimal heparinization and citrate anticoagulation appears to reduce coagulopathy.


Assuntos
Anastomose Cirúrgica/métodos , Aneurisma Aórtico/cirurgia , Perfusão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/mortalidade , Anastomose Cirúrgica/normas , Aneurisma Aórtico/complicações , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/cirurgia , Transfusão de Sangue Autóloga/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Procedimentos Cirúrgicos Torácicos/métodos , Procedimentos Cirúrgicos Torácicos/mortalidade , Procedimentos Cirúrgicos Torácicos/normas
15.
Ann Thorac Surg ; 69(4): 1251-3, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10800831

RESUMO

Traumatic aortic transection after acute deceleration injury remains a highly lethal condition. Concomitant aortic valve disruption is exceedingly rare, and can complicate the timing of surgical management. This report describes the management and outcome of a patient with these types of injuries.


Assuntos
Aorta Torácica/lesões , Aorta Torácica/cirurgia , Valva Aórtica/lesões , Ferimentos não Penetrantes/cirurgia , Acidentes por Quedas , Idoso , Aorta Torácica/diagnóstico por imagem , Desaceleração , Ecocardiografia Transesofagiana , Humanos , Masculino
16.
Genes Chromosomes Cancer ; 28(2): 133-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10824997

RESUMO

Cardiac lipomas occur infrequently but account for a significant portion of rare cardiac tumors. Common cutaneous lipomas have previously been associated with rearrangements of chromosome band 12q15, which often disrupt the high-mobility-group protein gene HMGIC. In this report, we describe the cytogenetic analysis of an unusual giant cardiac lipoma that exhibited myocardial invasion in a patient with a history of multiple lipomatosis (cutaneous lipoma, lipomatous gynecomastia, lipomatous hypertrophy of the interatrial septum, and dyslipidemia). Cytogenetic studies of cells derived from the cardiac lipoma demonstrated no abnormalities of chromosome 12, but did reveal a t(2;19)(p13;p13.2). A liposarcoma-derived oncogene (p115-RhoGEF) previously mapped to chromosome 19 and the low-density lipoprotein receptor gene (LDLR) previously mapped to chromosome band 19p13 were evaluated to determine whether they were disrupted by this translocation. Fluorescence in situ hybridization analyses assigned p115-RhoGEF to chromosome 19 in bands q13.2-q13.3 and mapped the LDLR to chromosome arm 19p in segment 13.2, but centromeric to the t(2;19) breakpoint. Thus, these genes are unlikely to be involved in the t(2;19)(p13;p13.2). Further studies of the regions of chromosomes 2 and 19 perturbed by the translocation in this unusual infiltrating cardiac lipoma will identify gene(s) that participate in adipocyte growth and differentiation and may provide insight into syndromes of multiple lipomatosis.


Assuntos
Cromossomos Humanos Par 19/genética , Cromossomos Humanos Par 2/genética , Neoplasias Cardíacas/genética , Neoplasias Cardíacas/patologia , Lipoma/genética , Lipoma/patologia , Lipomatose Simétrica Múltipla/genética , Lipomatose Simétrica Múltipla/patologia , Translocação Genética/genética , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica
19.
J Vasc Surg ; 29(5): 936-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10231645

RESUMO

Endoluminal stent graft repair of abdominal and thoracic aortic aneurysms is being performed in increasing numbers. The long-term benefits of this technology remain to be seen. Reports have begun to appear regarding complications of stent graft application, such as renal failure, intestinal infarction, distal embolization, and rupture. Many of these complications have been associated with a fatal outcome. We describe a case of acute, retrograde, type B aortic dissection after application of an endoluminal stent graft for an asymptomatic infrarenal abdominal aortic aneurysm. An extent I thoracoabdominal aortic aneurysm subsequently developed and was successfully repaired. Aggressive evaluation of new back pain after such a procedure is warranted. Further analysis of the short-term complications and long-term outcome of this new technology is indicated before universal application can be recommended.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Complicações Pós-Operatórias , Stents , Idoso , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Dor nas Costas/etiologia , Humanos , Masculino , Tomografia Computadorizada por Raios X
20.
Am J Gastroenterol ; 93(9): 1409-15, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9732917

RESUMO

OBJECTIVE: The aim of this study was to assess the effect of H. pylori eradication on ulcer recurrence in North American duodenal ulcer patients by examining only treatment studies that met rigorous methodologic criteria. METHODS: Data sources were computerized bibliographic searches from 1983, review of reference lists, communication with companies that manufacture medications used for H. pylori therapy in the U.S., and H. pylori investigators, review of open presentations to the Food and Drug Administration, and review of abstracts from annual scientific meetings. Criteria for study inclusion were double blind, randomized North American trials of H. pylori therapy for duodenal ulcer, scheduled endoscopic follow-up exams for > or = 6 months, and H. pylori cure documented > or = 4 wk after completion of therapy by at least two endoscopic biopsy tests. Seven relevant trials were identified. Data were abstracted independently and disagreement was resolved by consensus. We obtained missing data and identified erroneous assessments through contact with an author or sponsor of all studies. RESULTS: The common odds ratio for ulcer recurrence was 0.20 (95% CI, 0.13-0.31) and 2.8 patients would need to be successfully treated to prevent one ulcer recurrence at 6 months. The pooled ulcer recurrence rate at 6 months in patients with H. pylori eradication was 20%. CONCLUSION: Results of North American studies of highest methodological quality confirm that H. pylori eradication markedly decreases ulcer recurrence. Nevertheless, 20% of patients in these studies had ulcer recurrence within 6 months, despite successful cure of infection and no reported use of NSAIDs. Non-H. pylori, non-NSAID ulcers may be more common in the U.S. than previously believed.


Assuntos
Úlcera Duodenal/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Método Duplo-Cego , Úlcera Duodenal/microbiologia , Humanos , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Recidiva
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