A general technique for predicting the MODFET large signal performance has been developed. The technique is based entirely on experimental data (small signal S-parameters at different biased points) ...and therefore is independent of the structure of the FET. Software requirements include a program to fit an equivalent circuit to S parameter data; a simple least-square polynomial approximation program; and SPICE for nonlinear time-domain simulations. Hardware requirements are basically limited to a network analyzer to carry out the small-signal S parameter measurements. Measurements at 10 GHz confirm the validity of the model.< >
Abstract only
Background:
Postcapillary pulmonary hypertension (PH) has high prevalence and morbimortality. There are no large-animal models that fully reproduce postcapillary-PH. We aimed to develop ...and characterize a model that reproduced chronic postcapillary-PH including typical features in lungs and RV.
Methods:
Thirteen (10 banding, 3 sham) 4 week-old pigs underwent non-restrictive banding of the confluent of both inferior pulmonary veins. Chronic PH develops as the animal grows. Right heart catheterization and cardiac magnetic resonance (CMR) were performed immediately before and after the procedure and monthly thereafter during 4 months. Histopathology study of the heart and pulmonary vessels (Masson trichrome and picrosirius red staining) was performed at the end of the study.
Results:
All banded animals developed chronic PH. Compared to sham, mPAP in banded subjects was significantly higher after 1 month median (1st-3rd quartile): 26mmHg (25-31) vs. 21mmHg (14-22), p=0.03, increased progressively and reached a plateau after month 3 33mmHg (28-40) vs. 35mmHg (32-38) at months 3 and 4 respectively; Figure. PVR behaved similarly and achieved significance after 2 months 5.2WU (3.8-7.1) vs. 2.3WU (2.1-3.5), p=0.03. CMR demonstrated significant differences in indexed-RV end-systolic volume 42mL/m2 (36-53) vs. 24mL/m2 (24-33); p=0.03, indexed-RVmass 28g/m2 (27-29) vs.19g/m2 (18-23); p=0.02 and RVEF 59% (54-63) vs.66% (64-68); p=0.03 from the 2nd month and thereafter. Histopathology revealed vascular remodeling of pulmonary arteries including hypertrophy and fibrosis of the media, intimal fibrosis and RV myocardial disarray and fibrosis (Figure).
Conclusions:
We have successfully developed a large-animal model that produces chronic PH similar of that found in patients, associated with RV remodeling and typical pathology changes. The stability on PAP between months 3 and 4 makes this period the best to test therapies.
We describe results of a study comparing the magnetic field sensitivities of variable thickness bridge (VTB) arrays fabricated in TBCCO, BSCCO, and YBCO thin films. Identical structures were ...patterned in a variety of films, and the bridges were thinned by four different methods. Analysis of the data yields experimental evidence as to the suitability of these types of films for devices such as the superconducting flux flow transistor (SFFT) which is based on this geometry. The volt-ampere characteristics of the arrays were measured in low uniform magnetic fields (⩽130 G) and in nonuniform fields (⩽5 G) produced by a nearby control line. For these films in this geometry, no measurable effect of the control line magnetic field was observed. Large values of transresistance and current gain could only be attained through a thermal mechanism when the control line was driven normal. Upper bounds for (magnetically generated) transresistance (⩽5 mO) and current gains (⩽0.005) have been inferred from the uniform field data assuming a standard best-case device geometry. All volt-ampere curves followed closely a power law relationship (V~I n), with exponent n ~1.2-10. We suggest materials considerations that may yield improved device performance -
Peer Reviewed
Life expectancy after aortic valve replacement in young patients Hernández-Vaquero, Daniel; Rodríguez-Caulo, Emiliano; Vigil-Escalera, Carlota ...
Revista española de cardiología (English ed.),
April 2022, 2022-04-00, 20220401, Volume:
75, Issue:
4
Journal Article
Peer reviewed
In young patients with severe aortic stenosis, it is unknown whether their life expectancy restored after aortic valve replacement (AVR) is unknown.
We analyzed all patients aged between 50 and 65 ...years who underwent isolated AVR in 27 Spanish centers during an 18-year period. We compared observed and expected survival at 15 years of follow-up. We repeated all analyses for patients without complications in the postoperative period.
A total of 5084 patients were analyzed. For the overall sample, observed survival at 10 and 15 years was 85.3% (95%CI, 84.1%-86.4%) and 73.7% (95%CI, 71.6%-75.6%), respectively. Expected survival was 90.1% and 82.1%. Cumulative relative survival for 1, 5, 10 and 15 years of follow-up was 97.4% (95%CI, 96.9%-97.9%), 96.5% (95%CI, 95.7%-97.3%), 94.7% (95%CI, 93.3%-95.9%), and 89.8% (95%CI, 87.3%-92.1%). For patients without complications, cumulative relative survival for 1, 5, 10 and 15 years was 100.3% (95%CI, 99.8%-100.5%), 98.9% (95%CI 97.6% -99.9%), 97.3% (95%CI, 94.9%-99.4%), and 91.9% (95%CI, 86.5%-96.8%).
Life expectancy in young patients who have severe aortic stenosis and undergo AVR is lower than that of the general population. Life expectancy of individuals without complications during the postoperative period is also reduced. Therefore, baseline characteristics are likely the main factors that explain the reduction in life expectancy.
Se desconoce si los pacientes jóvenes con estenosis aórtica grave tienen una esperanza de vida restaurada tras el reemplazo de la válvula aórtica (RVAo).
Se incluyó a todos los pacientes entre 50 y 65 años sometidos a RVAo en 27 centros españoles durante 18 años. Se comparó la supervivencia observada y la esperada a los 15 años de seguimiento. Se repitieron todos los análisis con los pacientes sin complicaciones durante el posoperatorio inmediato.
Se analizó a 5.084 pacientes. En la muestra total, la supervivencia observada a los 10 y los 15 años fue del 85,3% (IC95%, 84,1-86,4%) y el 73,7% (IC95%, 71,6-75,6%). Las supervivencias esperadas fueron del 90,1 y el 82,1%. La supervivencia relativa acumulada a 1, 5, 10 y 15 años de seguimiento fue del 97,4% (IC95%, 96,9-97,9%), el 96,5% (IC95%, 95,7-97,3%), el 94,7% (IC95%, 93,3-95,9%) y el 89,8% (IC95%, 87,3-92,1%). Para los pacientes sin complicaciones, la supervivencia relativa acumulada a 1, 5, 10 y 15 años fue del 100,3% (IC95%, 99,8-100,5%), el 98,9% (IC95% 97,6-99,9%), el 97,3% (IC95%, 94,9-99,4%) y el 91,9% (IC95%, 86,5-96,8%).
La esperanza de vida de los pacientes jóvenes con estenosis aórtica grave intervenidos para RVAo es menor que la de la población general. La esperanza de vida de los pacientes sin complicaciones durante el posoperatorio inmediato también está reducida. Por lo tanto, las características basales probablemente sean los principales factores que explican la reducción de la esperanza de vida.
The purpose of our study was to show a distinctive appearance of exogenous lipoid pneumonia on thin-section CT that has not, to our knowledge, been previously documented.
On thin-section CT, ...exogenous lipoid pneumonia is revealed as patchy well-defined areas of ground-glass attenuation with superimposed septal thickening (crazy-paving pattern). Exogenous lipoid pneumonia should be included in the differential diagnosis when thin-section CT reveals a crazy-paving pattern.
The aim of this study was to investigate the incidence and prognostic value of disseminated tumor cells in bone marrow of breast carcinoma patients with early disease, and to analyze this finding in ...relation to lymph node involvement, determined by sentinel lymph node (SLN) biopsy analysis, and to prognostic factors of interest.
104 patients with operable (T<3 cm) breast cancer and clinically- and sonographically-negative axillary lymph nodes were scheduled for SLN biopsy. Bone marrow aspirates were collected before the start of surgery from both iliac crests, and mononuclear cell layers were separated by density centrifugation (Lymphoprep). Slide preparations were then examined for the presence of disseminated tumor cells by immunocytochemistry with anti-cytokeratin antibodies (A45-B/B3). Lymphoscintigraphy was performed 2 hours after intratumor administration of 2 mCi (74 MBq) of 99mTc colloidal albumin. The SLN was evaluated for the presence of tumor cells by hematoxylin-eosin staining and, when negative, by immunocytochemistry using anti-cytokeratin antibody (CAM 5.2). Survival analyses and comparative analyses were performed on the results of bone marrow determinations, SLN biopsy, and known prognostic factors, including breast cancer subtypes according to the simplified classification based on ER, PR and HER2.
Lymph node and hematogenous dissemination occur in one-third of patients with early-stage breast cancer, although not necessarily simultaneously. In our study, disseminated tumor cells were identified in 22% of bone marrow aspirates, whereas 28% of patients had axillary lymph node involvement. Simultaneous lymph node and bone marrow involvement was found in only 5 patients (nonsignificant). In the survival study (60 months), a higher, although nonsignificant rate of disease-related events (13%) was seen in patients with disseminated tumor cells in bone marrow, and a significant association of events was documented with the known, more aggressive tumor subtypes: triple negative receptor status (21%) and positive ERBB2 status (29%).
Tumor cell detection in bone marrow can be considered a valid prognostic parameter in patients with early disease. However, the classic prognostic factors remain highly relevant, and the newer breast cancer subtypes are also useful for this purpose.
An analysis of cardiac injury markers in patients with OSA who sustain an episode of acute coronary syndrome (ACS) may contribute to a better understanding of the interactions and impact of OSA in ...subjects with ACS. We compared peak cardiac troponin I (cTnI) levels in patients with OSA and patients without OSA who were admitted for ACS.
Blood samples were collected every 6 hours from the time of admission until two consecutive assays showed a downward trend in the cTnI assay. The highest value obtained defined the peak cTnI value, which provides an estimate of infarct size.
We included 89 patients with OSA and 38 patients without OSA with an apnea-hypopnea index of a median of 32 (interquartile range IQR, 20.8-46.6/h and 4.8 IQR, 1.6-9.6/h, respectively. The peak cTnI value was significantly higher in patients without OSA than in patients with OSA (median, 10.7 ng/mL IQR, 1.78-40.1 ng/mL vs 3.79 ng/mL IQR, 0.37-24.3 ng/mL; P = .04). The multivariable linear regression analysis of the relationship between peak cTnI value and patient group, age, sex, and type of ACS showed that the presence or absence of OSA significantly contributed to the peak cTnI level, which was 54% lower in patients with OSA than in those without OSA.
The results of this study suggest that OSA has a protective effect in the context of myocardial infarction and that patients with OSA may experience less severe myocardial injury. The possible role of OSA in cardioprotection should be explored in future studies.
Abstract Aim To assess the prevalence and prognostic power of disseminated tumor cells (DTC) in patients with locally advanced breast cancer (LABC) before primary systemic therapy (PST). Materials ...and methods LABC patients attending our Breast Unit were studied between 2002 and 2012, all of them being considered for PST. To determine the presence of DTC, posterior iliac crest aspirates were obtained and marrow samples were processed by gradient separation with Ficoll (Lymphoprep® ) and immunohistochemical staining using the antiCK A45-B/B3 (EPIMET) antibody. Clinicopathologic variables were recorded before and after PST to assess response. Disease-free survival (DFS) and overall survival (OS) were determined after follow-up. The presence of DTC as a predictor of response to PST and as a prognostic tool for OS and DSF was evaluated. Results DTC were observed in 26% of 47 patients included in the study. PST consisted of chemotherapy in 94% and hormone therapy in 6%. Breast-conserving therapy was attained in 33%. Mean follow-up was 68 months. Complete clinical response (CR) after PST was seen in 26%, disease recurrence in 38%, and cancer-related death in 8%; tumor size and negative estrogen receptors were significant predictors of CR and mastectomy was associated with DFS. Persistent axillary disease after PST and previous recurrence were predictive of OS. DTC were detected more often in patients who did not achieve CR and those who presented recurrence. DTC detection was a significant prognostic factor for a worse OS (OR = 7.62; CI95%: 1.46–39.61; p = 0.009) and a decreased survival time (62 versus 82 months, p = 0.004). Conclusion Presence of DTC before PST was found in a significant number of patients with LABC. DTC were found to be a significant prognostic factor for cancer-related death. DTC could be a surrogate predictor of response to PST and also of disease recurrence in LABC patients.
Program Life for Africa Carrera, José M; Cararach, Vicenc; Carrapato, Manuel R ...
Donald School Journal of Ultrasound in Obstetrics and Gynecology,
12/2011, Volume:
5, Issue:
4
Journal Article
Open access
ABSTRACT
Life for Africa is an international cooperation program that was developed by Matres Mundi International. It aims to improve the critical situation of maternal and infant health in Africa by ...improving the number and training of health professionals, particularly in the area of the maternal and infant health. The program, which is sponsored by the majority of the international societies of perinatal medicine (the International Academy of Perinatal Medicine, the World Association of Perinatal Medicine, etc.), consists of the creation of an International School of Perinatal Medicine for Africa and a Reference Hospital for Mothers and Children in Addis Abeba, capital of the African Union. This paper will discuss the reasons in favor of this project and will describe the details and the current situation. It will also provide information about the ‘exploratory mission’ that several members of Matres Mundi and the international societies made to Addis Abeba.
El recambio valvular aórtico (RVAo) quirúrgico puede modificar la historia natural de la estenosis aórtica grave (EAoG). Sin embargo, comparado con la población general, estos pacientes tienen una ...pérdida en su esperanza de vida. La esperanza de vida de los pacientes intervenidos de RVAo debido a EAoG de bajo gradiente con fracción de eyección del ventrículo izquierdo (FEVI) conservada se desconoce.
Se incluyó a todos los pacientes entre 50 y 65 años sometidos a RVAo quirúrgico aislado en 27 centros durante 18 años. Analizamos la supervivencia observada y esperada a los 18 años de pacientes con EAoG de bajo gradiente con FEVI conservada y todos los otros tipos de EAoG. Mediante emparejamiento basado en índice de propensión, comparamos la esperanza de vida de los pacientes con EAoG de bajo gradiente con FEVI conservada vs EAoG de alto gradiente con FEVI conservada.
Se analizó a 5.084 pacientes, 413 con EAoG de bajo gradiente con FEVI conservada. En estos pacientes, la supervivencia observada a 10, 15 y 18 años fue 86,6% (IC95%, 85,3-87,8), 75% (IC95%, 72,7-77,2) y 63,5% (IC95%, 58,8-67,8). La supervivencia esperada a 10, 15 y 18 años fue 90,2%, 82,1% y 75,7%. En la muestra emparejada, la supervivencia de los pacientes con EAoG de bajo gradiente con FEVI conservada fue similar a la de aquellos con EAoG de alto gradiente con FEVI conservada, test de log-rank p=0,95, HR=1 (IC95%, 0,7–1,4; p=0,95).
Existe una pérdida en la esperanza de vida en todos los tipos de EAoG después del RVAo. Esta pérdida es mayor en los pacientes con disfunción ventricular y menor en los pacientes con EAoG de bajo gradiente o alto gradiente con FEVI conservada. El beneficio de la cirugía es similar entre estos 2 últimos grupos.
Surgical aortic valve replacement (SAVR) can modify the natural history of severe aortic stenosis (SAS). However, compared with the general population, these patients have a loss of life expectancy. The life expectancy of patients who undergo SAVR due to low-gradient SAS with preserved left ventricular ejection fraction (LVEF) is unknown.
We included all patients between 50 and 65 years who underwent isolated SAVR in 27 Spanish centers during an 18-year period. We analyzed observed and expected survival at 18 years in patients with low-gradient SAS with preserved LVEF and all other types of SAS. We used propensity score matching to compare the life expectancy of patients with low-gradient SAS with preserved LVEF vs those with high-gradient SAS with preserved LVEF.
We analyzed 5084 patients, of whom 413 had low-gradient SAS with preserved LVEF. For these patients, observed survival at 10, 15 and 18 years was 86.6% (95%CI, 85.3-87.8), 75% (95%CI, 72.7-77.2), and 63.5% (95%CI, 58.8-67.8). Expected survival at 10, 15 and 18 years was 90.2%, 82.1%, and 75.7%. In the matched sample, survival of patients with low-gradient SAS with preserved LVEF was similar to that of patients with high-gradient with preserved LVEF, log-rank test, P=.95; HR=1 (95%CI, 0.7–1.4; P=.95).
There is a loss of life expectancy in patients with all types of SAS undergoing SAVR. This loss is higher in patients with left ventricular dysfunction and lower in patients with low-gradient or high-gradient aortic stenosis with preserved LVEF. The benefit of surgery is similar between these last 2 groups.
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