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2.
Cancers (Basel) ; 12(8)2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-32824635

RESUMEN

In order to meet the challenges in data evaluation and comparability between studies in multiple myeloma (MM) minimal residual disease (MRD) assessment, the goal of the current study was to provide a step-by-step evaluation of next-generation sequencing (NGS) and multicolor flow cytometry (MFC) data. Bone marrow (BM) sample pairs from 125 MM patients were analyzed by NGS and MFC MM MRD methods. Tumor load (TL) and limit of detection (LOD) and quantification (LOQ) were calculated. The best-fit MRD cut-off was chosen as 1 × 10-5, resulting in an overall 9.6% (n overall = 12 (NGS n = 2, MFC n = 10)) nonassessable cases. The overall concordance rate between NGS and MFC was 68.0% (n = 85); discordant results were found in 22.4% (11.2% (n = 14) of cases in each direction. Overall, 55.1% (n = 60/109) and 49.5% (n = 54/109) of patients with a serological response ≥ very good partial response (VGPR) showed BM MRD negativity by NGS and MFC, respectively. A good correlation in the TL assessed by both techniques was found (correlation coefficient = 0.8, n = 40, p < 0.001). Overall, our study shows good concordance between MM BM MRD status and TL when comparing NGS and MFC at a threshold of 10-5. However, a sufficient number of analyzed events and calculation of MRD key metrics are essential for the comparison of methods and evaluability of data at a specific MRD cut-off.

3.
Dermatol Ther (Heidelb) ; 10(4): 671-680, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32419097

RESUMEN

INTRODUCTION: Paediatric plaque psoriasis (PedPso) in children and adolescents is often diagnosed and treated for the first time by paediatricians. An early onset of psoriasis is associated with a genetic family burden, higher severity of disease and increased risk of comorbidities, sometimes starting in childhood. However, little information is available on prevalence data and the clinical management of PedPso by paediatricians. METHODS: A total of 191 questionnaires were sent out to paediatricians regarding their management of PedPso, with a focus on prevalence, diagnosis, initiation of therapies, screening for comorbidities and collaboration with dermatologists. Of these, 95 (49.7%) were returned and evaluated anonymously. RESULTS: Only about one-half of the responding paediatricians reported being certain in their diagnosis of PedPso, even though they regularly see moderate-to-severely affected patients. The questionnaire revealed that there are clear differences in the general management of PedPso if the paediatrician is not certain of the diagnosis of psoriasis. Compared to paediatricians certain of their diagnosis, those who are uncertain less frequently perform whole-body inspection, screen for relevant comorbidities, such as psoriasis arthritis, metabolic syndrome or mental disorders, and prescribe the use of topical or systemic therapies. No responding paediatrician reported the use of modern systemic therapies, such as biologicals, even in severely affected children. The majority of respondents rated their cooperation with dermatologists as good. CONCLUSION: The certainty of the diagnosis, the use of system therapies and the screening for comorbidity could improve the care of PedPso through targeted training of paediatricians and intensified interdisciplinary cooperation with dermatologist.

4.
J Am Chem Soc ; 140(3): 926-931, 2018 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-29182322

RESUMEN

It is a photochemist's dream to be able to photoinduce a reaction of a specific molecular species in an ensemble of similar but not identical ones. The problem is that similar molecules often exhibit nearly identical UV-Vis absorption spectra, making them difficult or impossible to distinguish or to select spectroscopically. The ultrafast VIPER (VIbrationally Promoted Electronic Resonance) pulse sequence allows to pick a single species for electronic excitation based on its infrared spectrum. The latter usually shows more features, allowing the discrimination between species than the UV-Vis spectrum. Here, we show that it is possible to induce and monitor species-selective photochemistry even for molecules with virtually identical UV-Vis spectra, which is the case for isotopomers. Next to isotope-selective photochemistry in solution, applications to orthogonal photo-uncaging and species-selective spectroscopy and photochemistry in mixtures are within reach.

5.
Artif Organs ; 36(8): 705-13, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22747979

RESUMEN

Cleveland Clinic's continuous-flow total artificial heart has one motor and one rotating assembly supported by a hydrodynamic bearing. The right hydraulic output is self regulated by passive axial movement of the rotating assembly to balance itself with the left output. The purpose of this article is to present progress in four areas of development: the automatic speed control system, self-regulation to balance right/left inlet pressures and flows, hemolysis testing using calf blood, and coupled electromagnetics (EMAG) and computational fluid dynamics (CFD) analysis. The relationships between functions of motor power and speed, systemic flow, and systemic vascular resistance (SVR) were used for the sensorless speed control algorithm and demonstrated close correlations. Based on those empirical relationships, systemic flow and SVR were calculated in the system module and showed good correlation with measured pump flow and SVR. The automatic system adjusted the pump's speed to obtain the target flow in response to the calculated SVR. Atrial pressure difference (left minus right atrial pressure) was maintained within ±10 mm Hg for a wide range of SVR/pulmonary vascular resistance ratios, demonstrating a wide margin of self-regulation under fixed-speed mode and 25% sinusoidally modulated speed mode. Hemolysis test results indicated acceptable values (normalized index of hemolysis <0.01 mg/dL). The coupled EMAG/CFD model was validated for use in further device development.


Asunto(s)
Corazón Artificial , Algoritmos , Animales , Bovinos , Diseño de Equipo , Eritrocitos/citología , Corazón Artificial/efectos adversos , Hemólisis , Humanos , Hidrodinámica , Modelos Cardiovasculares
6.
Artif Organs ; 34(12): 1158-63, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20545668

RESUMEN

The purpose of this study was to evaluate in vivo the biocompatibility of BioMedFlex (BMF), a new resilient, hard-carbon, thin-film coating, as a blood journal bearing material in Cleveland Heart's (Charlotte, NC, USA) continuous-flow right and left ventricular assist devices (RVADs and LVADs). BMF was applied to RVAD rotating assemblies or both rotating and stator assemblies in three chronic bovine studies. In one case, an LVAD with a BMF-coated stator was also implanted. Cases 1 and 3 were electively terminated at 18 and 29 days, respectively, with average measured pump flows of 4.9 L/min (RVAD) in Case 1 and 5.7 L/min (RVAD) plus 5.7 L/min (LVAD) in Case 3. Case 2 was terminated prematurely after 9 days because of sepsis. The sepsis, combined with running the pump at minimum speed (2000 rpm), presented a worst-case biocompatibility challenge. Postexplant evaluation of the blood-contacting journal bearing surfaces showed no biologic deposition in any of the four pumps. Thrombus inside the RVAD inlet cannula in Case 3 is believed to be the origin of a nonadherent thrombus wrapped around one of the primary impeller blades. In conclusion, we demonstrated that BMF coatings can provide good biocompatibility in the journal bearing for ventricular assist devices.


Asunto(s)
Carbono/metabolismo , Materiales Biocompatibles Revestidos/metabolismo , Corazón Auxiliar , Ensayo de Materiales , Animales , Carbono/efectos adversos , Bovinos , Materiales Biocompatibles Revestidos/efectos adversos , Hemodinámica , Agregación Plaquetaria , Implantación de Prótesis
7.
Cell Res ; 20(3): 288-98, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20101265

RESUMEN

Origin and fate of pancreatic stellate cells (PSCs) before, during and after pancreatic injury are a matter of debate. The crucial role of PSCs in the pathogenesis of pancreatic fibrosis is generally accepted. However, the turnover of the cells remains obscure. The present study addressed the issue of a potential bone marrow (BM) origin of PSCs. We used a model of stable hematopoietic chimerism by grafting enhanced green fluorescence protein (eGFP)-expressing BM cells after irradiation of acceptor rats. Chimerism was detected by FACS analysis of eGFP-positive cells in the peripheral blood. Dibutyltin dichloride (DBTC) was used to induce acute pancreatic inflammation with subsequent recovery over 4 weeks. Investigations have been focused on isolated cells to detect the resting PSC population. The incidence of eGFP-positive PSC obtained from the pancreas of chimeric rats was approximately 7% in healthy pancreatic tissue and increased significantly to a mean of 18% in the restored pancreas 4 weeks after DBTC-induced acute inflammation. Our results suggest that BM-derived progenitor cells represent a source of renewable stellate cells in the pancreas. Increased numbers of resting PSCs after regeneration point toward enhanced recruitment of BM-derived cells to the pancreas and/or re-acquisition of a quiescent state after inflammation-induced activation.


Asunto(s)
Células de la Médula Ósea/citología , Páncreas/citología , Células Madre/citología , Actinas/metabolismo , Animales , Quimera , Desmina/metabolismo , Femenino , Citometría de Flujo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Inmunohistoquímica , Modelos Animales , Compuestos Orgánicos de Estaño/toxicidad , Fenotipo , Ratas , Regeneración , Células Madre/metabolismo
8.
J Heart Lung Transplant ; 29(1): 21-6, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19782590

RESUMEN

BACKGROUND: The purpose of this study was to evaluate the acute in vivo pump performance of a unique valveless, sensorless, pulsatile, continuous-flow total artificial heart (CFTAH) that passively self-balances left and right circulations without electronic intervention. METHODS: The CFTAH was implanted in two calves, with pump and hemodynamic data recorded at baseline over the full range of pump operational speeds (2,000 to 3,000 rpm) in 200-rpm increments, with pulsatility variance, and under a series of induced hemodynamic states created by varying circulating blood volume and systemic and pulmonary vascular resistance (SVR and PVR). RESULTS: Sixty of the 63 induced hemodynamic states in Case 1 and 73 of 78 states in Case 2 met our design goal of a balanced flow and maximum atrial pressure difference of 10 mm Hg. The correlation of calculated vs measured flow and SVR was high (R(2) = 0.857 and 0.832, respectively), allowing validation of an additional level of automatic active control. By varying the amplitude of sinusoidal modulation of the speed waveform, 9 mm Hg of induced pulmonary and 18 mm Hg of systemic arterial pressure pulsation were achieved. CONCLUSIONS: These results validated CFTAH self-balancing of left and right circulation, induced arterial flow and pressure pulsatility, accurate calculated flow and SVR parameters, and the performance of an automatic active control mode in an acute, in vivo setting in response to a wide range of imposed physiologic perturbations.


Asunto(s)
Circulación Asistida/instrumentación , Circulación Sanguínea/fisiología , Corazón Artificial/normas , Corazón Auxiliar/normas , Algoritmos , Animales , Bovinos , Hemodinámica/fisiología , Masculino , Modelos Animales , Flujo Pulsátil/fisiología , Resistencia Vascular/fisiología
9.
Immunopharmacol Immunotoxicol ; 31(4): 595-600, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19874228

RESUMEN

Treosulfan (Treo) and total body irradiation (TBI) demonstrate a high therapeutic activity in treatment of acute leukemia and lymphoma. We investigated the combination of Treo and TBI prior to bone marrow transplantation (BMT) in rats. Female Lewis rats were treated with Treo on 3 consecutive days followed by TBI with either 5 Gy (n = 28) or 7.5 Gy (n = 48). After conditioning animals received 4 x 10E7 bone marrow cells (BC) from female Lewis rats. Additional 16 rats were transplanted with 4 x 10E7 BC and 1.5 x 10E7 spleen T-cells from female Brown-Norway (BN) rats. Animals were examined daily for clinical signs and toxicity was investigated by necropsy and histology in all animals. Gastrointestinal toxicity was the dose-limiting factor of Treo in combination with TBI. The highest tolerable dose of Treo in combination with 7.5 Gy TBI was 3 x 0.5 g/kg and the highest tolerable dose of Treo in combination with 5 Gy TBI was 3 x 0.6 g/kg. Allogeneic BMT from BN donors resulted in engraftment and survival of 12 out of 16 animals. Gastrointestinal toxicity is the dose-limiting factor in the treatment with Treo and TBI. Furthermore, Treo possesses certain characteristics of a radiosensitizer.


Asunto(s)
Trasplante de Médula Ósea/inmunología , Busulfano/análogos & derivados , Acondicionamiento Pretrasplante , Irradiación Corporal Total , Animales , Trasplante de Médula Ósea/métodos , Busulfano/farmacología , Terapia Combinada/métodos , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Femenino , Supervivencia de Injerto/efectos de los fármacos , Supervivencia de Injerto/inmunología , Ratas , Ratas Endogámicas BN , Ratas Endogámicas Lew , Acondicionamiento Pretrasplante/métodos , Irradiación Corporal Total/métodos
10.
J Gen Virol ; 90(Pt 5): 1281-1288, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19264612

RESUMEN

Several dsRNA bands (approx. 0.6-7 kbp in size) were recovered from tissues of mosaic-diseased fig seedlings which contained the enveloped round structures known as double membrane bodies (DMBs). blast analysis of a 4353 and a 1120 nt sequence from the two largest RNA segments showed homology with the polymerase and the putative glycoprotein precursor genes of negative-sense single-stranded RNA viruses of the family Bunyaviridae. Negative- and positive-sense riboprobes designed from both RNA segments hybridized to two bands of approximately 7 and 2.3 kbp in Northern blots of dsRNAs. Thus, these segments were identified as putative RNA-1 and RNA-2 of a novel virus for which the name fig mosaic virus (FMV) is proposed. Identity levels of predicted amino acids of the protein encoded by FMV RNA-1 with those of species of the family Bunyaviridae and European mountain ash ringspot-associated virus (EMERaV) were 28 and 54 %, respectively. RNA-2 showed 38 % identity at the amino acid level only with EMARaV. RNA-1 segment contained five conserved motifs (A-E) and an endonucleolytic centre of comparable genes of L RNA of bunyaviruses and EMARaV RNA-1. In a phylogenetic tree constructed with RdRp sequences, EMARaV grouped with FMV in a clade distinct from those of all bunyavirus genera. The consistent association of DMBs with mosaic symptoms and the results of molecular investigations strongly indicate that DMBs are particles of FMV, the aetiological agent of fig mosaic disease.


Asunto(s)
Ficus/virología , Enfermedades de las Plantas/virología , Virus de Plantas/genética , Virus de Plantas/aislamiento & purificación , Virus ARN/genética , Secuencia de Aminoácidos , Clonación Molecular , Datos de Secuencia Molecular , Filogenia , Hojas de la Planta/ultraestructura , Hojas de la Planta/virología , Proteínas Virales/química
11.
ASAIO J ; 53(6): 730-3, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18043157

RESUMEN

The PediPump is a passive magnetic bearing, mixed flow, rotary ventricular assist device designed to provide support for the entire range of patient sizes encountered in pediatrics. Blood enters axially at the inlet and is accelerated and turned in the impeller to exit the pump at an intermediate angle. The size of the PediPump facilitates standard cannulation strategies with substantially downsized components. The program pursues three specific objectives: 1) System engineering: Progress within the last year has focused on the assembly and testing of PediPump prototypes. Initial in vitro hydraulic performance and hemolysis testing were judged satisfactory. 2) Anatomic fitting studies: As part of the PediPump program, three-dimensional modeling techniques based on routine, clinically obtained computerized tomography (CT) scans have been developed. During 2006, the same techniques developed for clinical scans were applied to CT scans obtained from sheep to guide the presurgical planning. 3) Animal studies: Animal implantation of PediPump prototypes commenced in July 2006. A total of four 6 hour acute studies were performed throughout the remainder of the year. In vivo performance was satisfactory and compared well with the in vitro results. Hemolysis levels were low.


Asunto(s)
Ingeniería Biomédica , Corazón Auxiliar , Animales , Animales Recién Nacidos , Fenómenos Fisiológicos Sanguíneos , Cadáver , Bovinos , Niño , Preescolar , Hemodinámica , Hemólisis/fisiología , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Diseño de Prótesis , Ajuste de Prótesis , Implantación de Prótesis , Ovinos , Tomografía Computarizada por Rayos X
12.
ASAIO J ; 53(6): 766-70, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18043163

RESUMEN

The PediPump is a small ventricular assist device (VAD) with a hydraulic output range designed to support children from newborns to adolescents. The present report describes our initial evaluation of the PediPump as a left VAD in an acute sheep model. The PediPump was implanted in two sheep (50.8 and 62.7 kg). Pump speed was adjusted to achieve a flow of 2 L/min with the naturally occurring preload and afterload conditions to evaluate pump performance under a steady hemodynamic state for 4 hours. Upon completion, pump performance was evaluated under various blood pressure and heart rate conditions. During steady-state evaluations, the ascending aortic flow and pump speed varied slightly depending on systemic arterial pressure variations. During the hemodynamic manipulation studies, flows ranged between 0.5 and 3.2 L/min with pump speeds of 5,200-16,200 rpm and motor current of 0.06-0.75 A. The PediPump demonstrated good initial hemodynamic performance for use as an implantable left VAD. However, some depositions were detected at the time of explanation, mainly at the rear of the pump. We are continuing with further acute studies to evaluate pump performance in anticipation of beginning chronic studies to evaluate long-term biocompatibility.


Asunto(s)
Ingeniería Biomédica , Corazón Auxiliar , Animales , Análisis Químico de la Sangre , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Hemoglobinas/análisis , Hemólisis , Magnetismo , Masculino , Nitroprusiato/farmacología , Fenilefrina/farmacología , Diseño de Prótesis , Implantación de Prótesis , Rotación , Ovinos , Factores de Tiempo , Vasoconstrictores/farmacología , Vasodilatadores/farmacología , Función Ventricular Izquierda
13.
J Gen Virol ; 88(Pt 4): 1337-1346, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17374780

RESUMEN

Four RNAs from a new plant-pathogenic virus, which we have tentatively named European mountain ash ringspot-associated virus (EMARAV), were identified and sequenced completely. All four viral RNAs could be detected in previous double-stranded RNA preparations. RNA 1 (7040 nt) encodes a protein with similarity to the RNA-dependent RNA polymerase of different members of the Bunyaviridae, a family containing five genera with viruses infecting invertebrates, vertebrates and plants. RNA 2 (2335 nt) encodes a 75 kDa protein containing a conserved motif of the glycoprotein precursor of the genus Phlebovirus. Immunological detection indicated the presence of proteins with the expected size of the precursor and one of its processing products. The amino acid sequence of protein p3 (35 kDa) encoded by RNA 3 shows similarities to a putative nucleocapsid protein of two still unclassified plant viruses. The fourth viral RNA encodes a 27 kDa protein that has no significant homology to any known protein. As is typical for members of the family Bunyaviridae, the 5' and 3' ends of all viral RNAs are complementary, which allows the RNA to form a panhandle structure. Comparison of these sequences demonstrates a conserved terminal part of 13 nt, similar to that of the bunyaviral genus Orthobunyavirus. Despite the high agreement of the EMARAV genome with several characteristics of the family Bunyaviridae, there are a few features that make it difficult to allocate the virus to this group. It is therefore more likely that this plant pathogen belongs to a novel virus genus.


Asunto(s)
Enfermedades de las Plantas/virología , Virus ARN/clasificación , Virus ARN/aislamiento & purificación , ARN Viral/genética , Sorbus/virología , Secuencia de Aminoácidos , Secuencia de Bases , Bunyaviridae/genética , ADN Complementario , Datos de Secuencia Molecular , Proteínas de la Nucleocápside/genética , Orthobunyavirus , Phlebovirus/genética , Virus ARN/genética , ARN Viral/aislamiento & purificación , ARN Polimerasa Dependiente del ARN/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Homología de Secuencia de Aminoácido
14.
ASAIO J ; 52(5): 581-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16966863

RESUMEN

The PediPump is a new ventricular assist device with a hydraulic output range designed for children from newborn infants to adolescents. The design is based on a mixed-flow rotary pump; the rotating assembly consists of a front impeller, front and rear radial magnetic bearings, and a central motor magnet. Two different implantable pumps were designed initially: an intravascular pump measuring 7 x 75 mm and an extravascular pump measuring 14 x 85 mm. Current prototypes are substantially smaller: The current intravascular version measures 4.5 x 55 mm, whereas the current extravascular version measures 11 x 70 mm. Both devices provide pressure and flows capable of supporting adults, far exceeding the initially defined physiologic requirements for children weighing 2 to 25 kg. This basic pump design may be used in acute or chronic clinical settings to provide right ventricular, left ventricular, or biventricular support. There are three objectives for the PediPump development program: 1) determination of basic engineering requirements for hardware and control logic including design analysis for system sizing, evaluation of control concepts, and bench testing of prototypes; 2) performance of preclinical anatomic fitting studies using CT-based 3D modeling; and 3) animal studies to provide characterization and reliability testing of the device.


Asunto(s)
Corazón Auxiliar , Adolescente , Ingeniería Biomédica , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Diseño de Prótesis , Ajuste de Prótesis
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