199,324 research outputs found
Activity-rest stimulation protocol improves cardiac assistance in dynamic cardiomyoplasty
No full textEur J Cardiothorac Surg. 2002 Mar;21(3):478-82.
Activity-rest stimulation protocol improves cardiac assistance in dynamic cardiomyoplasty.
Rigatelli G, Carraro U, Barbiero M, Zanchetta M, Dimopoulos K, Cobelli F, Riccardi R, Rigatelli G.
Source
Department of Cardiology, Interventional Cardiology Lab and Cardiomyoplasty Project Unit, Legnago General Hospital, Verona, Italy. [email protected]
Abstract
OBJECTIVE:
No data have ever been published regarding cardiac assistance in demand dynamic cardiomyoplasty (DDCMP). We tested the efficacy of the Doppler flow wire in measuring beat-to-beat aortic flow velocity and evaluating cardiac assistance in demand cardiomyoplasty patients.
METHODS:
The technique was tested in seven patients (M/F=6/1; age=57.1+/-6.2 years; atrial fibrillation/sinus rhythm=1/6; NYHA=1.4+/-0.5). Measurements were done using a 0.018inch peripheral Doppler flow wire advanced through a 5F arterial femoral sheath. Three 1-min periods with the stimulator off and three 1-min periods with clinical stimulation were recorded. We measured peak aortic flow velocity in all beats. Latissimus dorsi (LD) mechanogram was simultaneously recorded.
RESULTS:
Comparison between pre-operative and follow-up data showed significantly higher values of tetanic fusion frequency (TFF) and ejection fraction at follow-up, whereas mean NYHA class was significantly lower. Statistical analysis showed an increase in aortic flow velocity not only in assisted versus rest period, but also in assisted versus unassisted beats (8.42+/-6.98% and 7.55+/-3.07%). A linear correlation was found between the increase in flow velocity and LD wrap TFF (r(2)=0.53).
CONCLUSIONS:
In DDCMP, systolic assistance is significant and correlated to LD speed of contraction; demand stimulation protocol maintains muscle properties and increases muscle performance.
PMID:
11888767
[PubMed - indexed for MEDLINE
Current and future treatment options for infections caused by multidrugresistant Gram-negative pathogens
No full textThe spread of multidrug-resistant, extensively drug-resistant and pan-drug-resistant pathogens is causing an unprecedented public health crisis. The limited current therapeutic options led to the revival of two 'old' antibiotics - colistin and fosfomycin - for which a better understanding of their pharmacokinetics in the critically ill patient and in specific body compartments is required. Tigecycline's use in clinical practice for nonapproved indication based on its in vitro activity against problematic pathogens requires caution and probably higher doses. Furthermore, all three antibiotics should be used as part of combination regimens in order to prevent resistance and optimize outcomes. The development of new antibacterials in the near future, namely combinations of avibactam, ceftolozane/tazobactam and plazomicin, seems promising; however, they will only partially address current mechanisms of resistanc
New advances in dynamic cardiomyoplasty: Doppler flow wire shows improved cardiac assistance in demand protocol
No full textASAIO J. 2002 Jan-Feb;48(1):119-23.
New advances in dynamic cardiomyoplasty: Doppler flow wire shows improved cardiac assistance in demand protocol.
Rigatelli G, Carraro U, Barbiero M, Zanchetta M, Pedon L, Dimopoulos K, Rigatelli G, Maiolino P, Cobelli F, Riccardi R, Volta SD.
Source
Department of Cardiology, Legnago General Hospital, Verona, Italy.
Abstract
No data have been published on real cardiac assistance with demand dynamic cardiomyoplasty. We tested the utility of a Doppler flow wire in measuring beat by beat aortic flow velocity and evaluating cardiac assistance in demand cardiomyoplasty patients. The technique was tested in seven patients (M/W = 6/1; age, 57.1+/-6.2 years; atrial fibrillation/ sinus rhythm = 1/6; New York Heart Association [NYHA] classification = 1.4+/-0.5). Measurements were done using a 0.018 inch peripheral Doppler flow wire advanced through a 5 French arterial femoral sheath. Three 1 minute periods with the stimulator off, and three 1 minute periods with clinical stimulation were recorded. We measured peak aortic flow velocity in all beats. Latissimus dorsi mechanogram was simultaneously recorded. Comparison between preoperative and follow-up data showed significantly higher values of tetanic fusion frequency and ejection fraction at follow-up, whereas mean NYHA class was significantly lower. Statistical analysis showed an increase in aortic flow velocity not only in the assisted versus rest period, but also in assisted versus unassisted beats (8.42+/-6.98% and 7.55+/-3.07%). A linear correlation was found between increase in flow velocity and latissimus dorsi wrap tetanic fusion frequency (r2 = 0.53). In demand dynamic cardiomyoplasty, systolic assistance is significant and correlated to the latissimus dorsi speed of contraction; a demand stimulation protocol maintains muscle properties and increases muscle performance.
PMID:
11814090
[PubMed - indexed for MEDLINE
FIGURE 2 in Typification of the names Verbascum limnense and Celsia tomentosa (Scrophulariaceae) and a new nothospecies, V. × sipiadense, with the hybrid formula V. limnense × V. sinuatum
No full textFIGURE 2. Lectotype of Celsia tomentosa Zucc. kept in M (M-0244375).Published as part of Zografidis, Aris, Esser, Hans-Joachim, Dimopoulos, Panayotis & Raus, Thomas, 2022, Typification of the names Verbascum limnense and Celsia tomentosa (Scrophulariaceae) and a new nothospecies, V. × sipiadense, with the hybrid formula V. limnense × V. sinuatum, pp. 214-220 in Phytotaxa 542 (2) on page 217, DOI: 10.11646/phytotaxa.542.2.9, http://zenodo.org/record/641802
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
Elderly versus non-elderly patients with intra-abdominal candidiasis in the ICU
No full textIntra-abdominal candidiasis (IAC) has a considerable cost in terms of mortality and morbidity. We sought to study the epidemiology, characteristics and outcome of elderly (>75 years old) versus non-elderly patients with IAC and risk factors for mortality in elderly patients
Examining the relationship between total species richness and single island palaeo- and neo-endemics
No full textRecently, Emerson and Kolm (2005) hypothesized that diversity begets speciation (DBS hypothesis). The relationship between total species richness and single island endemic diversity (as a proportion of the total species richness of the island) has been used as evidence for the DBS hypothesis. This relationship has been documented in oceanic archipelagos, but many criticisms have been raised on whether this relationship truly supports the DBS hypothesis. In this study we tested if this hypothesis holds in the Aegean archipelago (a continental archipelago with continuous human presence over millennia). Endemism in the Aegean includes mainly neo-endemic species but also relictual populations of formerly more widespread species (i.e. palaeo-endemics). Contrary to the DBS hypothesis, we found that total species richness was not significantly correlated to single island endemics (neither neo-endemics nor palaeo-endemics) as a proportion of the island flora. Furthermore, we found that neo-endemic diversity (either as species richness or as a proportion of the islands flora) is mainly correlated to island maximum elevation, while area and isolation were less important. So if this ratio is indeed an index of speciation, then an alternative explanation might be that elevation (interpreted as a proxy for habitat heterogeneity) is the driver of speciation in our case. Palaeo-endemics, on the other hand, were present in only six of the largest islands in the Aegean and their diversity was strongly correlated only with island area, perhaps implying that larger islands support larger population sizes that buffer stochastic extinctions risks. (C) 2010 Elsevier Masson SAS. All rights reserved
Real-time simulation of the effects of catalyst on automotive engines performance
No full textRestrictions on pollutant emissions nowadays force the use of catalyst-based after-treatment systems both in SI and in Diesel engines. The use of a honeycomb support is an established practice: however, to overcome drawbacks such as poor flow homogenization, the use of ceramic foams has been recently investigated [1,...] as an alternative showing better conversion efficiencies (but with higher pressure losses).
The proposed paper is aimed at evaluating the effects of these supports on engine performance through a 0D “crank-angle” mathematical model developed by the Authors in Simulink® for real-time calculations [2,3]. This tool has been enhanced improving the heat exchange model of the exhaust manifold to take account of thermal dynamics during transients. Besides a 0D model of the catalyst has been developed to simulate mass flow and thermal processes. Gas temperature at the catalyst outlet is calculated from energy conservation equation taking account of thermal inertia of the system and considering convective heat exchange between gas and monolith and thermal energy from the partial oxidation of unburnt compounds.
The model has been used to simulate an actual 1.6l turbocharged Diesel with EGR during an EUDC driving cycle comparing honeycomb and foam catalysts. Results reported in the paper show the effects of these supports on pressure changes in intake and exhaust manifolds, on fuel consumption and on variations of catalyst temperatures during the considered transients
- …
