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1.
Internist (Berl) ; 60(10): 1102-1105, 2019 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-31451847

RESUMEN

A 46-year-old immunosuppressed patient presented with a breast implant-associated infection 10 years after breast augmentation in Southeast Asia. No pathogen was identified in the initial conventional microbiological workup. Subsequently, infection with Mycobacterium abscessus-a nontuberculous mycobacteria-was diagnosed using a special culture technique. Increased rates of such infections are reported after cosmetic surgery in foreign countries, presumably due to inoculation with these ubiquitous pathogens. This case highlights the fact that the differential diagnosis and thus the microbiological workup should be extended in cases without initial pathogen detection.


Asunto(s)
Implantes de Mama/efectos adversos , Cuerpos Extraños/microbiología , Mastodinia/etiología , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Micobacterias no Tuberculosas/aislamiento & purificación , Infecciones Relacionadas con Prótesis/microbiología , Infección de la Herida Quirúrgica/microbiología , Implantes de Mama/microbiología , Fiebre/etiología , Humanos , Huésped Inmunocomprometido , Persona de Mediana Edad , Infecciones por Mycobacterium no Tuberculosas/microbiología
2.
Angiogenesis ; 21(4): 883-900, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30014172

RESUMEN

VEGF induces normal or aberrant angiogenesis depending on its dose in the microenvironment around each producing cell in vivo. This transition depends on the balance between VEGF-induced endothelial stimulation and PDGF-BB-mediated pericyte recruitment, and co-expression of PDGF-BB normalizes aberrant angiogenesis despite high VEGF doses. We recently found that VEGF over-expression induces angiogenesis in skeletal muscle through an initial circumferential vascular enlargement followed by longitudinal splitting, rather than sprouting. Here we investigated the cellular mechanism by which PDGF-BB co-expression normalizes VEGF-induced aberrant angiogenesis. Monoclonal populations of transduced myoblasts, expressing similarly high levels of VEGF alone or with PDGF-BB, were implanted in mouse skeletal muscles. PDGF-BB co-expression did not promote sprouting and angiogenesis that occurred through vascular enlargement and splitting. However, enlargements were significantly smaller in diameter, due to a significant reduction in endothelial proliferation, and retained pericytes, which were otherwise lost with high VEGF alone. A time-course of histological analyses and repetitive intravital imaging showed that PDGF-BB co-expression anticipated the initiation of vascular enlargement and markedly accelerated the splitting process. Interestingly, quantification during in vivo imaging suggested that a global reduction in shear stress favored the initiation of transluminal pillar formation during VEGF-induced splitting angiogenesis. Quantification of target gene expression showed that VEGF-R2 signaling output was significantly reduced by PDGF-BB co-expression compared to VEGF alone. In conclusion, PDGF-BB co-expression prevents VEGF-induced aberrant angiogenesis by modulating VEGF-R2 signaling and endothelial proliferation, thereby limiting the degree of circumferential enlargement and enabling efficient completion of vascular splitting into normal capillary networks despite high VEGF doses.


Asunto(s)
Becaplermina/metabolismo , Proliferación Celular , Células Endoteliales , Músculo Esquelético , Neovascularización Fisiológica , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Células Endoteliales/citología , Células Endoteliales/metabolismo , Ratones , Ratones SCID , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/citología , Músculo Esquelético/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
3.
Int J Behav Med ; 25(6): 669-681, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30132272

RESUMEN

PURPOSE: This study investigates the social determinants of health by examining how mucosal immunity is associated with the patterning of social connections in a network. Studies have suggested that social networks have biological underpinnings, but investigations at the scale of networks, rather than individuals, have remained elusive. We integrate salivary bioscience methods with advanced social network modeling to explore the association between salivary secretory immunoglobulin A (SIgA), a key component of mucosal immunity, and social network structure. METHOD: Friendship network data and saliva samples (later assayed for SIgA) were obtained from a large mixed-gender social organization (n = 155, 55% female, M age = 19.5 years). RESULTS: Exponential random graph modeling revealed that SIgA levels were positively associated with reporting more friendship ties with community members (i.e., social network activity), after controlling for other processes associated with network structure including preference to befriend others of the same age, gender, and extraversion, increased network popularity of agreeable individuals and those with lower levels of perceived stress, as well as network structural and organizational processes. CONCLUSION: By examining a wider range of associations between SIgA and network structure, we pinpoint that SIgA is positively associated with respondent's sociability. Our findings are consistent with social integration theories linking social relationships to health and highlight the role of humoral immunity as a possible mediator of these associations.


Asunto(s)
Amigos , Inmunoglobulina A Secretora/inmunología , Saliva/inmunología , Red Social , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven
4.
Microsurgery ; 37(5): 431-435, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27571547

RESUMEN

In this report, we present two cases of the bony reconstruction with the medial trochlea (MFT) flap including a skin island that was used to monitor the perfusion of flap in the postoperative period. Between March 2013 and April 2015, we performed surgery on two patients who suffered from scaphoid and talus non-union after trauma and initial treatment by osteosynthesis. A skin island (1 cm × 1 cm and 3 cm × 1 cm, respectively) was included with the osseous flap (1.6 cm × 1 cm × 1 cm and 2 cm × 3 cm × 2 cm, respectively) to assess the perfusion of the flap. The design of the skin island was based on either the saphenous artery perforator or a cutaneous perforator of the descending genicular artery. Both flaps remained viable throughout the postoperative period, and there were no donor site complications. After a follow-up of 36 and 11 months, bony union was observed in both patients with a high degree of satisfaction. Thus, a MFT flap with a skin island could be a tool to assess the perfusion of the flap in the early postoperative period. © 2016 Wiley Periodicals, Inc. Microsurgery 37:431-435, 2017.


Asunto(s)
Fracturas no Consolidadas/cirugía , Colgajos Tisulares Libres/trasplante , Procedimientos de Cirugía Plástica/métodos , Hueso Escafoides/lesiones , Astrágalo/lesiones , Femenino , Colgajos Tisulares Libres/irrigación sanguínea , Humanos , Rodilla , Masculino , Persona de Mediana Edad , Hueso Escafoides/cirugía , Astrágalo/cirugía , Adulto Joven
5.
J Environ Qual ; 53(1): 90-100, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37940131

RESUMEN

Splitting fertilizer nitrogen (N) applications and using cover crops are management strategies to reduce nitrate in tile drainage water. We investigated split fertilizer N applications to corn (Zea mays L.) on crop yields and tile nitrate loss in both corn and soybean (Glycine max L.) in rotation from 2016 through 2019. We evaluated the inclusion of cover crops in a split-N treatment. Fertilizer N treatments included 100% in the fall; 50% in the fall + 25% at planting + 25% at side-dress; 100% as spring preplant; 75% as spring preplant (reduced N rate); 50% as spring preplant + 50% at side-dress; and 50% as spring preplant + 50% at side-dress with a cover crop. We did not find significant differences between split and single full rate N application treatments for corn yields or tile nitrate loss; however, the reduced N rate treatment significantly decreased corn yield by 10%. Cumulative tile nitrate losses (over four seasons) ranged from 115 kg ha-1 for all of the N in the fall to 65 kg ha-1 for 50% as spring preplant + 50% at side-dress with a cover crop, a decrease of 43%. Tile nitrate loss responded similarly to (corn) N treatments under both corn and soybean, with 64% of the loss under corn and 36% under soybean. Our results suggest that decreasing the fertilizer N rate may impact corn yield more than nitrate loss, while split fertilizer N application with a cover crop has potential to reduce tile nitrate loss without decreasing crop yield.


Asunto(s)
Glycine max , Zea mays , Nitratos/análisis , Agricultura/métodos , Secale , Fertilizantes/análisis , Grano Comestible/química , Nitrógeno/análisis , Productos Agrícolas , Suelo
6.
Pract Radiat Oncol ; 14(3): e205-e213, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38237893

RESUMEN

PURPOSE: Significant heterogeneity exists in clinical quality assurance (QA) practices within radiation oncology departments, with most chart rounds lacking prospective peer-reviewed contour evaluation. This has the potential to significantly affect patient outcomes, particularly for head and neck cancers (HNC) given the large variance in target volume delineation. With this understanding, we incorporated a prospective systematic peer contour-review process into our workflow for all patients with HNC. This study aims to assess the effectiveness of implementing prospective peer review into practice for our National Cancer Institute Designated Cancer Center and to report factors associated with contour modifications. METHODS AND MATERIALS: Starting in November 2020, our department adopted a systematic QA process with real-time metrics, in which contours for all patients with HNC treated with radiation therapy were prospectively peer reviewed and graded. Contours were graded with green (unnecessary), yellow (minor), or red (major) colors based on the degree of peer-recommended modifications. Contours from November 2020 through September 2021 were included for analysis. RESULTS: Three hundred sixty contours were included. Contour grades were made up of 89.7% green, 8.9% yellow, and 1.4% red grades. Physicians with >12 months of clinical experience were less likely to have contour changes requested than those with <12 months (8.3% vs 40.9%; P < .001). Contour grades were significantly associated with physician case load, with physicians presenting more than the median number of 50 cases having significantly less modifications requested than those presenting <50 (6.7% vs 13.3%; P = .013). Physicians working with a resident or fellow were less likely to have contour changes requested than those without a trainee (5.2% vs 12.6%; P = .039). Frequency of major modification requests significantly decreased over time after adoption of prospective peer contour review, with no red grades occurring >6 months after adoption. CONCLUSIONS: This study highlights the importance of prospective peer contour-review implementation into systematic clinical QA processes for HNC. Physician experience proved to be the highest predictor of approved contours. A growth curve was demonstrated, with major modifications declining after prospective contour review implementation. Even within a high-volume academic practice with subspecialist attendings, >10% of patients had contour changes made as a direct result of prospective peer review.


Asunto(s)
Neoplasias de Cabeza y Cuello , Garantía de la Calidad de Atención de Salud , Humanos , Neoplasias de Cabeza y Cuello/radioterapia , Garantía de la Calidad de Atención de Salud/normas , Planificación de la Radioterapia Asistida por Computador/métodos , Planificación de la Radioterapia Asistida por Computador/normas , Estudios Prospectivos , Femenino , Oncología por Radiación/normas , Oncología por Radiación/métodos , Masculino
7.
Allergy ; 68(5): 659-65, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23464577

RESUMEN

BACKGROUND: Nasal polyposis frequently occurs within the clinical picture of aspirin-exacerbated respiratory disease (AERD). A derailed arachidonic acid metabolism is regarded to be part of the pathophysiology of AERD, and aspirin desensitization is the only causal therapeutic option, so far. The optimal maintenance dose of aspirin desensitization to prevent nasal polyp recurrence on the one hand and to minimize aspirin-related side-effects, on the other hand, is still a matter of debate. The aim of this trial was to investigate the efficacy and safety of a low-dose aspirin desensitization protocol. METHODS: After sinus surgery, 70 individuals with AERD were randomly allocated to a prospective double-blind placebo-controlled aspirin desensitization protocol with a maintenance dose of 100 mg daily. The primary outcome was polyp relapse after 36 months. Nasal endoscopy status, quality of life, and patients' symptom score as well as aspirin-related side-effects were monitored. RESULTS: Due to the high dropout rate, only 31 individuals were evaluated. After 36 months, nasal polyp relapse was less frequent (P = 0.0785) and the polyposis score was lower (P = 0.0702) in the therapy group. Quality of life obviously improved (P = 0.0324), clinical complaints (P = 0.0083) were significantly reduced, and no severe aspirin-related side-effects were observed. CONCLUSION: Aspirin desensitization with a maintenance dose of 100 mg daily has a positive impact on nasal polyp relapse and seems to be a safe and suitable therapy to improve clinical complaints and the quality of life of individuals with AERD.


Asunto(s)
Aspirina/administración & dosificación , Desensibilización Inmunológica , Hipersensibilidad a las Drogas/terapia , Hipersensibilidad Respiratoria/terapia , Adulto , Aspirina/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Recurrencia , Encuestas y Cuestionarios , Resultado del Tratamiento
8.
Handchir Mikrochir Plast Chir ; 55(2): 95-105, 2023 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-36780931

RESUMEN

BACKGROUND: Research is an integral part of academic medicine. In plastic surgery, it sets the course for innovations in the specialty. The purpose of this study is to present the research performance of plastic surgeons in Germany for the period 2021/2022 and to compare it with previous periods. MATERIALS AND METHODS: The directors of plastic surgical academic institutions reported all requested/approved and rejected research applications to public, non-public and industrial funding organizations. Data was gathered within an established online database. In addition, the DFG´s public database GEPRIS was screened for plastic surgical research grants. Data was also collected regarding research infrastructure and organization at the participating centers. RESULTS: 105 applications were reported to 54 different funding agencies from 20 plastic surgery centers. 37 funding applications were submitted to the major public funding agencies DFG, BMBF, BMWi, BMG, BMVg, G-BA and EU. Of these, 59,5% (22/37) were DFG, 13,5% (5/37) each BMBF and EU, 5,4% (2/37) BMWi, and 2,7% (1/37) each BMG, BMVg, and G-BA applications. The average funding volume of these proposals was 401,515 euros. Approved DFG proposals were most frequently assigned to the review board 205-27 Orthopedics, Trauma Surgery, Reconstructive Surgery (n=10/16, 62,5%). Over time, the research registry shows an increase in the number of proposals in general and those granted. 70,0% (14/20) of participating sites had their own experimental research laboratory, while only 40,0% (8/20) had their own clinical trial center. CONCLUSION: The 2021/2022 Research Funding Report once again highlights the impressive research accomplishments of the plastic surgery community.


Asunto(s)
Procedimientos de Cirugía Plástica , Cirujanos , Cirugía Plástica , Humanos , Sistema de Registros , Estética
12.
Vet Pathol ; 49(2): 313-21, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21551426

RESUMEN

From 2002 to 2007, 101 camelid abortions and stillbirths were submitted to the Veterinary Diagnostic Laboratory at Oregon State University (84 alpacas [Vicugna pacos], 13 llamas [Lama glama], 4 unknown). For most cases (n = 67), a cause was not determined by routine testing. Eighty-five submissions included placenta for microscopic examination, of which 55 were from abortions to unknown causes (idiopathic). Microscopic features of placentas from abortion/stillbirth were compared with those from 19 camelids delivered normally (6 alpacas, 12 llamas, 1 unknown) and with those from 4 alpaca fetuses of known gestational age collected during the dam's necropsy. The most common microscopic findings in abortion/stillbirth placentas were mineralization (n = 57) and mucinous edema (n = 27) of the chorioallantoic stroma. One or more of these features were also observed in 22 of 23 placentas from normal pregnancies/deliveries and therefore interpreted as incidental findings. The comparison of alpaca placentas after matching for gestational parameters (crown-rump length, weight, days of gestation; n = 41) revealed hypoplasia of placental villi in 5 of 22 idiopathic abortions and in 1 abortion due to umbilical torsion; hypoplasia was further suspected in an additional 6 abortions of unknown cause and 2 abortions of known cause. The identified villous hypoplasia is assumed to have resulted in placental insufficiency. When placental insufficiency is included as cause, idiopathic abortions are reduced from 66.2 to 47.9% of alpaca cases with histopathologic examination of placenta and from 66.3 to 52.5% of alpaca and llama abortions overall. This study also permitted the generation of a linear regression curve correlating alpaca fetal crown-rump length with fetal age.


Asunto(s)
Aborto Veterinario/patología , Camélidos del Nuevo Mundo , Placenta/patología , Insuficiencia Placentaria/veterinaria , Complicaciones del Embarazo/veterinaria , Mortinato/veterinaria , Animales , Femenino , Peso Fetal , Edad Gestacional , Masculino , Mucinas/metabolismo , Placenta/anomalías , Placenta/anatomía & histología , Insuficiencia Placentaria/patología , Embarazo , Complicaciones del Embarazo/patología , Estudios Prospectivos , Estudios Retrospectivos
15.
Aesthetic Plast Surg ; 35(6): 1133-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21512868

RESUMEN

Anchoring a flap remains a key procedure in decubital surgery because a flap needs to be stable against shearing forces. This allows an early mobilization and undisturbed primary wound healing. This study evaluated a uniform group of eight paraplegic patients with sacral decubital ulcers and covered the lesions using gluteal rotation flaps with a deepithelialized tip to anchor the flap subcutaneously on the contralateral ischial tuber. Initial wound healing and recurrence after one year were evaluated. All but one flap showed uneventful wound healing, and all the flaps presented without any signs of recurrence or instability. The authors suggest that sufficient anchoring using a deepithelialized part of the flap helps to integrate and stabilize sacral rotation flaps.


Asunto(s)
Procedimientos de Cirugía Plástica/métodos , Úlcera por Presión/cirugía , Colgajos Quirúrgicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
16.
Vet J ; 274: 105712, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34182073

RESUMEN

Pathogenic free-living amoebae, most notably Acanthamoeba spp., are important pathogens of the human cornea. The importance of infection with free-living amoebae in cats with keratitis is currently unclear. The aim of this study was to determine the frequency of amoeba detection in corneas of cats with naturally-acquired keratitis and in the ocular surface microflora of cats without ocular disease. Clinical ophthalmic and in vivo corneal confocal microscopic examinations were performed on 60 cats with keratitis. Corneal scrapings were analyzed by amoeba culture; cytological evaluation; and Acanthamoeba, Hartmannella, and Vahlkampfia PCR assays. Following ophthalmic examination, conjunctival specimens collected from 60 cats without clinically apparent ocular disease were analyzed similarly. In one cat with ulcerative keratitis, amoeba cysts and trophozoites were detected by in vivo corneal confocal microscopy; an Acanthamoeba sp. was isolated from corneal specimens and detected by Acanthamoeba PCR assay; and suppurative corneal inflammation was present cytologically. An Acanthamoeba sp. was isolated from conjunctival specimens from one cat without clinically apparent ocular disease, but with suppurative inflammation demonstrated cytologically. Both Acanthamoeba isolates belonged to the T4 genotype. Naegleria-like amoebae were isolated in samples from two cats with keratitis and seven cats without clinical ocular disease, but amoebae were not detected by the other assays in these samples. Amoeba detection by culture was significantly (P = 0.01) associated with cytologically diagnosed corneoconjunctival inflammation. This study identified naturally-acquired Acanthamoeba keratitis in cats. Detection of Naegleria-like amoebae in samples from cats with and without keratitis is of uncertain pathological significance.


Asunto(s)
Amoeba/aislamiento & purificación , Enfermedades de los Gatos/parasitología , Córnea/parasitología , Queratitis/veterinaria , Acanthamoeba/clasificación , Acanthamoeba/aislamiento & purificación , Queratitis por Acanthamoeba/parasitología , Queratitis por Acanthamoeba/veterinaria , Amoeba/clasificación , Animales , Gatos , Córnea/patología , Femenino , Queratitis/parasitología , Masculino
17.
Handchir Mikrochir Plast Chir ; 53(2): 110-118, 2021 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-32977347

RESUMEN

BACKGROUND: Since 2015/16 the DGPRÄC collects, evaluates and publishes the research activities of academic sections, departments and clinics for plastic surgery at university hospitals in Germany, in order to raise the awareness of plastic surgical research performance. MATERIALS AND METHODS: The directors of plastic surgical academic institutions were contacted via the DGPRÄC and asked to report any requested/approved and rejected research applications to public, non-public and industrial funding organizations. Data was collected in our previously established online database: https://docs.google.com/forms/d/e/1FAIpQLSe6F5xmTyw-k7VKJx_2jkPA4LBXsA0sgBGMrC3rx_4bHj6uzQ/viewform?usp=sf_link. In addition, applications were identified via the DFG's public database GEPRIS. RESULTS: A total of 41 funding applications to the public funding institutes DFG, BMBF, BMWi, BMG and EU were identified. 75.6 % (31/41) of the applications had already been approved at the time of data collection, of which 77.4 % (24/31) were DFG, 9.7 % (3/31) were BMWi, 6.5 % (2/31) were EU and 3.2 % (1/31) were BMBF or BMG applications. The average funding amounted to 358 301 Euro. In 50.0 % (12/24) of the cases, the approved DFG proposals were assigned to the subject review board 205-27 Orthopedics, Trauma Surgery, Reconstructive Surgery. CONCLUSION: The continuous publication of plastic surgical research funding reports submitted by the convention of university plastic surgeons of the DGPRÄC portraits the excellent, collaborative research activity in the field of plastic surgery.


Asunto(s)
Procedimientos de Cirugía Plástica , Cirujanos , Cirugía Plástica , Estética , Alemania , Humanos , Sistema de Registros
18.
Handchir Mikrochir Plast Chir ; 52(2): 140-146, 2020 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-32259860

RESUMEN

BACKGROUND: The formation of professional networks and cooperations - in addition to any qualified good education - seems fundamental for a successful career. In a number of disciplines, various symposia or conferences exist. In the field of microsurgery, however, a specific, guided and designated opportunity for junior scientists to network with one another has been missing so far. METHODS: In 2017, a science academy was initiated for the first time by the German-speaking Association for Nerves and Vessels (DAM) with the goal of bringing together and networking microsurgically researching young physicians and scientists. This was intended to happen on a small scale once a year in order to develop synergies for joint research projects. For this purpose, motivated junior researchers were individually selected by their mentors and sent to the academy by the boards of research institutions that are organized in the DAM. After getting to know each other in a relaxed atmosphere, the participants were given the opportunity to present their respective research project within the framework of thematic blocks and moderated by experienced mentors. Each presentation was followed by a round table discussion and small group work, in which knowledge and methods were exchanged and points of contact for possible later cooperation were identified. RESULTS: In the past 3 years, the DAM Science Academy proved to be an optimal format to initiate and promote networks of young researchers comprising microsurgically interested physicians and scientists. There were many lively and in-depth discussions, which were mainly due to the open working atmosphere and the obligation to confidentiality. Most of the synergies were shown i. a. in the field of angiogenesis, bioreactor, carcinoma-ADSC interactions, stem cells, AV loop model, ischemia/reperfusion, and nerve regeneration. The participants consistently gave a very positive feedback in the final evaluation with the wish to continue this academy. CONCLUSION: The DAM Science Academy can be considered a highly suitable complemental platform to the existing networking opportunities among microsurgical researchers. Experience so far suggests that this will hopefully result in long-term cooperations and a permanent transfer of knowledge among the participants.


Asunto(s)
Microcirugia , Consenso
19.
J Cell Mol Med ; 13(8B): 2593-2601, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19067768

RESUMEN

A novel therapeutic approach for the treatment of bone defects is gene therapy assisted bone tissue engineering using bone marrow stromal cells (hBMSC). The aim of this study was to investigate the influence of human epidermal growth factor (hEGF) on proliferation and alkaline phosphatase (AP) activity of primary hBMSC in vitro. hBMSC cultures were achieved by explantation culture of bone chips. Following exposure to 0-10 ng recombinant hEGF (rhEGF)/ml cell numbers were determined by automated cell counting and cell bound AP activity was measured spectrophotometrically. hBMSC were transfected with hEGF plasmids and the proliferative effect was studied by cocultivation of transfected and untreated cells using porous cell culture inserts. The persistence of hEGF expression even after cell transfer was studied by the generation of possibly osteogenic constructs introducing transfected hBMSC in fibrin glue and bovine cancellous bone. The maximum increase in proliferation (156 +/- 7%) and AP activity (220 +/- 34%) was detected after exposition to 10 ng rhEGF/ml. In the separation chamber assay transfected cells produced hEGF concentrations up to 3.6 ng/ml, which induced a mean proliferation increase of 93% which could be significantly inhibited by a neutralizing hEGF antibody. Further, EGFsecretion of transfected hBMSC in 3D-culture was verified. Recombinant and transgenic hEGF stimulate proliferation of primary hBMSC in vitro. Lipotransfection of hBMSC with hEGF plasmids allows the transient and site directed delivery of biologically active transgenic hEGF. The introduction of mitogenic, angiogenic and chemoattractive factors in gene therapy assisted bone tissue engineering is discussed by the example of EGF.


Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Células del Estroma/efectos de los fármacos , Ingeniería de Tejidos , Transfección , Células de la Médula Ósea/citología , Medios de Cultivo , Ensayo de Inmunoadsorción Enzimática , Humanos , Proteínas Recombinantes/efectos de los fármacos , Células del Estroma/citología
20.
Science ; 180(4092): 1293-5, 1973 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-4575121

RESUMEN

The time dependence of the intensity of light scattered from motile Escherichia coli bacteria is studied in population densities so low that the intensity autocorrelation function reflects fluctuations in the total number of particles in the scattering region. Measured correlation functions are analyzed by using a random walk model of bacterial motion.


Asunto(s)
Escherichia coli/fisiología , Luz , Rayos Láser , Matemática , Movimiento , Dispersión de Radiación , Factores de Tiempo
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