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PubMed2005

Effects of prenatal irradiation with an accelerated heavy-ion beam on postnatal development in rats: I. Neurophysiological alterations.

Effects on postnatal neurophysiological development in offspring were studied after exposure of pregnant Wistar rats to accelerated carbon-ion beams with an LET of about 13 keV/ mum at doses ranging from 0.1 Gy to 2.5 Gy on the 15th day of gestation. The age at which four physiological markers appeared and five reflexes were acquired was examined prior to weaning. Gain in body weight was monitored until the offspring were 3 months old. Male offspring were evaluated as young adults using two behavioral tests. The effects of X rays estimated for the same biological end points were studied for comparison. For most of the end points at early age, no significant alterations were observed in offspring that received prenatal irradiation with 0.1 Gy of either accelerated carbon ions or X rays compared to the offspring of sham-irradiated dams. However, all offspring whose dams received 2.5 Gy died prior to weaning. Offspring from dams irradiated with accelerated carbon ions generally showed higher incidences of prenatal death and preweaning mortality, markedly delayed accomplishment in their physiological markers and reflexes, and gain in body weight compared to those exposed to X rays at doses of 0.5 to 2 Gy. Significantly reduced ratios of main organ weight to body weight at the postnatal ages of 30, 60 and 90 days were also observed within this dose range. The results indicate that irradiation with 0.5 to 2 Gy on day 15 of gestation caused permanent alterations in offspring that were dependent on dose. The alterations include permanent growth retardation, morphological malformations in main organs, including microcephaly, diminished reflex attainment, delayed appearance of physiological markers, and changes in adult behavior. Exposure to 1 to 2 Gy of radiation resulted in growth retardation and behavioral alterations that persisted throughout life. Accelerated carbon ions generally induced more detrimental effects than X rays.

Abnormalities, Radiation-Induced↗

PubMed2001

Short-chain carboxylic acids produced by gram-negative anaerobic bacteria can accelerate or delay polymorphonuclear leukocyte apoptosis in vitro.

BACKGROUND: Short-chain carboxylic acids (SCCA) are metabolic byproducts of anaerobic subgingival bacteria associated with human periodontal disease. We examined the effect of 4 SCCA (butyric, propionic, succinic, and lactic acids) on human polymorphonuclear leukocyte (PMN) apoptosis over the range of concentrations (1 to 30 mM) found in the diseased periodontium. METHODS: PMN suspensions were incubated at 37 degrees C with medium alone (control) or one of the 4 SCCA at concentrations of 1, 5, or 30 mM. Aliquots were withdrawn hourly to assess apoptosis and viability by fluorescence microscopy. RESULTS: Relative to untreated controls, PMN incubated for at least 5 hours with 1 mM butyric or propionic acids exhibited significant delays in apoptosis (P<0.05), while those incubated with succinic or lactic acids exhibited no significant differences from controls (P>0.05). At a concentration of 5 mM, propionic, succinic, and lactic acids had little effect on apoptosis (P>0.05), but butyric acid significantly accelerated apoptotic changes (P<0.05). At 30 mM, all SCCA except lactic acid significantly accelerated apoptosis (P<0.05). Incubation with SCCA did not adversely affect cell viability (typically >98%). Lysates from PMN incubated 6 hours with 30 mM butyric or propionic acids contained significantly more caspase-3 activity than lysates from untreated control PMN (P<0.05). Moreover, pretreatment with a specific inhibitor of caspase-3 blocked acceleration of PMN apoptosis by butyric or propionic acids (P<0.05). CONCLUSION: Low concentrations of butyric or propionic acids delay PMN apoptosis and extend their functional lifespan, while higher concentrations accelerate apoptosis through a mechanism that appears to involve caspase-3.

Analysis of Variance↗

PubMed1998

Cystic fibrosis: predictors of accelerated decline and distribution of disease in 230 patients.

OBJECTIVE: The purpose of this study was to determine predictors of accelerated deterioration in radiographic manifestations of cystic fibrosis. The incidence and distribution of focally accentuated disease were also studied. MATERIALS AND METHODS: From 230 patients, 3038 chest radiographs were scored using the Brasfield system. Scores were plotted against age, and a single age-based severity curve was created. Specific observations (at least one episode in the first 5 years of life of air trapping, linear markings, nodular cystic lesions, or large lesions) were assessed to determine predictors of accelerated decline in scores compared with the aggregate scores plotted in the age-based severity curve. Specific observations were noted as present or absent and graded as to severity. A specific observation was counted as present if seen on at least one occasion. (The number of occasions on which the observation was made did not affect statistical analysis.) We also evaluated the distribution of lung disease by assessing the severity and nature of disease through specific lobar distribution. RESULTS: Males showed a slightly greater rate of radiologic decline. Early development of air trapping or bronchiectasis was associated with an accelerated rate of decline over time. Lobe-dominant disease occurred in one third of all images and in two thirds of the patients. It varied with age in its incidence, location, and etiology. CONCLUSION: Hyperinflation or bronchiectasis that occurs before age 5 is associated with accelerated radiographic deterioration. The incidence and location of lobe-dominant disease varied with age in these patients.

Adolescent↗

PubMed1992

Poly I:C accelerates development of diabetes mellitus in diabetes-prone BB rat.

We developed a new experimental model of accelerated diabetes mellitus in the genetically susceptible diabetes-prone BB rat with the administration of the IFN-alpha inducer poly I:C. With this model, there was both an increased incidence and accelerated onset of insulin-dependent-diabetes in poly I:C-treated animals compared with saline-treated controls. All twelve rats administered poly I:C (5 micrograms/gm body weight 3 times/wk) developed diabetes by 57 days of age (100%) compared with 1 of 27 (3.7%) saline-treated controls. Furthermore, the development of diabetes was accelerated in the poly I:C-treated group (mean age +/- SE at onset 52.8 +/- 0.58 days) compared with saline-treated controls (89.3 +/- 2.4 days, P less than 0.01). Additionally, poly I:C-treated rats had higher mean serum IFN-alpha levels than saline-treated rats at weeks 2 and 3 of treatment (210 vs. 27 and 183 vs. 25 U/ml, respectively, P less than 0.001). Poly I:C treatment of 5 Wistar rats, the parental strain, which is not susceptible to diabetes, did not result in insulitis, diabetes, or hyperglycemia. The histopathologic findings of insulitis and decreased immunoreactive islet insulin in poly I:C-accelerated diabetic BB rats and in BB rats with spontaneous diabetes suggest a similar pathophysiology.

Analysis of Variance↗

PubMed2001

Vitamin-mineral supplementation and accelerated chilling effects on quality of pork from pigs that are monomutant or noncarriers of the halothane gene.

We examined the effects of vitamin and mineral supplementation of the finishing diet on growth and accelerated chilling of carcasses on carcass and muscle traits of halothane gene carrier and noncarrier pigs. Barrows and gilts that were either monomutants (MON, n = 49) or noncarriers (NON, n = 28) of the halothane gene were fed a standard finishing diet until they reached 86 kg. They then were randomly assigned to one of four finishing diets formulated to contain 11 IU/kg vitamin E (0), 311 IU/kg vitamin E plus additional vitamins and minerals (300), 611 IU/kg vitamin E plus additional vitamins and minerals (600), or 911 IU/kg vitamin E plus additional vitamins and minerals (900) until they were slaughtered (118 kg). Alternating carcass sides were assigned either a normal chilling procedure (NC, 4 degrees C for 24 h) or an accelerated chilling procedure (AC, -20 degrees C for 1.5 h and then 4 degrees C for 22.5 h). Supplementing vitamin E in the finishing diet increased (P < 0.05) the concentration of vitamin E in the longissimus muscle. Supplementing vitamin E in the diets of MON pigs did not affect color, firmness, or cooking losses of loins or color and firmness of hams. For the NON genotype, increasing the level of vitamin E in the diet decreased (P < 0.05) the percentage of PSE loins and hams. Color and firmness scores of the gluteus medius and longissimus muscles were improved 0.4 unit (P < 0.005) by AC compared with NC of carcasses. Loin chop juiciness and flavor were improved (P < 0.05) in the MON genotype for AC compared to NC. Accelerated chilling reduced (P < 0.05) the percentage of PSE loins from 38 to 17% and PSE hams from 32 to 10% for the MON genotype, but percentage of PSE was not affected (P > 0.05) by chilling treatment for the NON genotype. No interaction between diet and chill treatments existed for muscle quality traits (P > 0.05). Supplementing finishing diets of NON pigs with at least 600 IU/kg vitamin E, in addition to other vitamins and minerals, or accelerated chilling of MON carcasses can reduce the incidence of PSE pork.

Animals↗

PubMedDate not supplied

Acceleration levels at hearing threshold with direct bone conduction versus conventional bone conduction.

Some patients with hearing disorders cannot use a conventional air conduction hearing aid, but have to use a bone conduction hearing aid. The technique of introducing a permanent, skin-penetrating titanium implant has made it possible to develop a bone-anchored hearing aid with all parts in a single housing. Ten patients have been using such an aid for almost 2 years. This investigation deals with absolute acceleration threshold measurements in 7 of these patients. The measuring apparatus consisted mainly of a Békésy audiometer and an accelerometer, Brüel & Kjaer 4344. In the frequency range from 250 to 6 000 Hz, the acceleration levels at hearing threshold decreased by between 16 and 28 dB when measured directly on the titanium screw, as compared with when measured on the intact skin surface. This lowering in acceleration thresholds can be explained by the fact that skin and subcutaneous soft tissues act as a shunt for acceleration.

Adolescent↗

PubMedDate not supplied

Smooth pursuit in senescence. Effects of target acceleration and velocity.

Smooth pursuit responses to sinusoidal and triangular waveform targets were investigated in elderly and middle-aged subjects. The middle-aged pursued triangular targets with significantly lower gain than sinusoidal targets. In the elderly, pursuit gain was significantly lower than in the middle-aged under all target conditions. When all smooth eye movements at a constant frequency were correlated with varying target velocity, pursuit gain was uniformly reduced in the elderly, irrespective of target velocity up to 63 degrees/s or accelerations up to 395 degrees/s2. Within these limits, the steady-state gain of pursuit was depressed. At higher target accelerations having the same velocity range, smooth pursuit velocities were further reduced in the elderly. Senescent tracking is depressed by involvement of the steady-state gain element of the pursuit system at low target accelerations and by acceleration saturation at higher demands.

Adult↗

PubMedDate not supplied

Eye movements induced by gravitational force and by angular acceleration: their relationship.

The relationship between putative 'canal' and 'otolith' function was studied by using both vertical axis and horizontal axis (barbecue spit) rotations. The vestibulo-ocular reflex (VOR) with eyes closed of 7 normal subjects during vertical axis rotation was characterized (0.02 to 1.67 Hz) using pseudorandom acceleration. Gain and phase points were calculated. The long time constant of the VOR was then estimated from the phase points using a simple linear systems model. The same subjects were also tested with eyes closed using earth horizontal axis rotations. Constant velocity rotation (60 degrees/sec) produced a periodic oscillation in the slope of the slow component of nystagmus known as the 'modulation component'. The amplitude of this component was averaged for clockwise and counterclockwise runs. For the 7 subjects, the amplitude of averaged modulation component correlated with the low-frequency phase values (r = 0.82 to 0.89) and VOR long time constant estimates (r = -0.95) obtained during vertical axis rotations. These data suggest a complementary relationship between responses to linear and to angular accelerations. Subjects having eye movement responses which are less sensitive to low-frequency angular acceleration also tend to have relatively greater responses to changing linear accelerations.

Eye Movements↗

PubMedDate not supplied

Ultrastructural evidence of cell-mediated endothelial cell injury in cardiac transplant-related accelerated arteriosclerosis.

Accelerated arteriosclerosis secondary to chronic allograft rejection is a major long-term complication of heart transplantation. Accelerated arteriosclerosis has been associated with an endothelialitis, and the majority of the involved inflammatory cells are T lymphocytes and macrophages. Coronary arteries from six heart allograft recipients with transplant-related arteriosclerosis were examined by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Four hearts were explants from heart transplant recipients with severe accelerated arteriosclerosis who were undergoing retransplantation, and two were obtained from autopsied recipients. The patients ranged in age from 6 to 60 years (mean, 44 years). The graft survival for these six hearts ranged from 1.4 to 5.6 years (mean, 4.3 years). Lymphocytes, macrophages, and smooth muscle cells were identified by TEM in the intimas of all the vessels examined. The lymphocytes were often in contact with macrophages or in close proximity to injured endothelial cells. Areas of endothelial injury were characterized by vacuolization of endothelial cells and partial denudation of the endothelium with fibrin deposition. SEM also revealed endothelial cell injury with disorganization of the endothelium and gaps between endothelial cells. Leukocytes and platelets were often noted in these gaps. These findings suggest that accelerated arteriosclerosis in heart transplant recipients is associated with an accumulation of macrophages, lymphocytes, and smooth muscle cells in the intima as well as with lymphocyte-directed endothelial injury.

Adult↗

PubMed1988

Accelerated fractionation in the radiation treatment of head and neck cancer. A critical comparison of different strategies.

There is strong clinical and radiobiological evidence that protraction of overall treatment time has an adverse influence on the radiocurability of certain human tumors. Overall treatment time can be reduced without recourse to large dose fractions by the use of accelerated fractionation, but in patients with head and neck cancer acute mucosal reactions limit the extent to which treatment can be accelerated. Three different prototypical schedules for accelerated fractionation have been devised to avoid exceeding acute mucosal tolerance. Type A consists of an intensive short course in which the overall duration of treatment is markedly decreased with a corresponding substantial reduction of total dose; type B achieves a modest decrease in overall time without reduction of total dose by using a split-course technique; type C also achieves a modest decrease in overall time without reduction of total dose by means of the concomitant boost technique. A hybrid schedule combining features of types B and C allows additional shortening of overall treatment time without reduction of total dose. Available radiobiological and clinical data suggest that schedules of types B or C which do not compromise total dose are generally preferable to those of type A in which there is a trade-off between total dose and overall time. For a given total dose and overall time, a continuous treatment of type C is likely to produce more cell kill than a split-course of type B, although the latter will be better tolerated. Because of the increased acute toxicity associated with all schedules of accelerated fractionation, rational selection of patients for such treatment is important. New techniques to measure the potential doubling time of human tumors in vivo offer this prospect.

Clinical Trials as Topic↗

PubMed2003

Late course accelerated hyperfractionated radiotherapy for clinical T1-2 esophageal carcinoma.

AIM: This retrospective study was designed to analyze the results and the failure patterns of late course accelerated hyperfractionated radiotherapy for clinical T(1-2)N(0)M(0) esophageal carcinoma. METHODS: From Aug. 1994 to Feb. 2001, 56 patients with clinical T(1-2) esophageal carcinoma received late course accelerated hyperfractionated radiotherapy in Cancer Hospital, Fudan University. All patients had been histologically proven to have squamous cell carcinoma (SCC) and were diagnosed to be T(1-2)N(0)M(0) by CT scan. All patients were treated with conventional fractionation (CF) irradiation during the first two-thirds course of the treatment to a dose of about 41.4Gy/23fx/4 to 5 weeks, Which was then followed by accelerated hyperfractionation irradiation using reduced fields, twice daily at 1.5Gy per fraction, to a dose about 27Gy/18 fx. Thus the total dose was 67-70Gy/40-43fx/40-49 d. RESULTS: The 1-, 3- and 5-year overall survival was 90.9 %, 54.6 %, 47.8 % respectively. The 1-, 3- and 5-year local control rate was 90.9 %, 84.5 % and 84.5 %, respectively. Twenty-five percent (14/56) patients had distant metastasis and/or lymph nodes metastasis alone. Eight point nine percent (5/56) patients had local disease alone. Another 3.6 % (2/56) patients had regional relapse and distant metastasis. CONCLUSION: Late course accelerated hyperfractionated radiotherapy is effective on clinical T(1-2) esophageal carcinoma. The main failure pattern is distant metastasis.

Aged↗

PubMed2001

Effects of supine body position and low radial accelerations on the visually perceived apparent zenith.

The visually perceived eye level (VPEL) has been shown to shift toward the lower part of the body in upright subjects facing toward the axis of rotation on a centrifuge. This shift occurs in the same direction as the shift in the gravito-inertial forces (Gis) produced by very low radial acceleration (centrifugation) combined with gravity. The purpose of this study was to determine whether the same phenomenon affects the visually perceived apparent zenith (VPAZ) in subjects in a supine position. Twelve supine subjects were instructed to set a luminous target to the VPAZ, either while they were in total darkness and motionless or while undergoing very low centrifugation. Data showed that Gis induced a VPAZ shift similar to that observed for the VPEL. Thus, as is the case for the VPEL, the corresponding logarithmic psychophysical function of the VPAZ may be considered to be a type of oculogravic illusion phenomenon with differences in the subjects' that differs from subject to subject, depending on the subject's sensitivity to low radial accelerations. Data on VPEL and VPAZ support the notion that the subjective perception of eye level in total darkness takes into account changes--even if extremely slight-in the direction of the gravito-inertial forces produced by the combination of gravity and low radial accelerations, although subjects are unaware of the Gi shift. However, depending on the intensity of the radial acceleration and the angular deviation of Gi relative to G, the shift of the VPEL and the VPAZ can be either amplified or attenuated. Moreover, differences between VPEL and VPAZ responses suggest two explanatory assumptions--namely, that this is (1) a peripheral phenomenon dependent on the neurophysiological anisotropy of the otolithic system or (2) a central phenomenon dependent on the relevance assigned to the peripheral information by the integrative sensory functions and the associative processes.

Adult↗

PubMed2001

H-2D end confers dominant protection from IL-10-mediated acceleration of autoimmune diabetes in the nonobese diabetic mouse.

BALB/c mice that express IL-10 as a transgene in their pancreatic beta cells (Ins-IL-10 mice) do not develop diabetes, even after crossing to nonobese diabetic (NOD) mice ((Ins-IL-10 x NOD)F(1) mice). However, backcross of F(1) mice to NOD mice (NOD.Ins-IL-10 mice) results in N2 and N3 generations that develop accelerated diabetes. In this study, we found that NOD.Ins-IL-10 mice that expressed BALB/c-derived MHC molecules (NOD.Ins-IL-10(H-2(g7/d)) mice) were protected from diabetes. This protection associated with peri-islet infiltration and preserved beta cell function. Moreover, expression of I-A(d) and I-E(d) MHC class II molecules of BALB/c origin was not responsible for protection, but NOD.Ins-IL-10 mice that expressed BALB/c MHC class I D(d) molecules (NOD.Ins-IL-10(H-2(g7/d)) mice) did not develop diabetes. To directly test the possibility of a protective role of H-2D(d) in the development of accelerated diabetes, we generated transgenic mice expressing D(d) under the control of the MHC class I promoter. We found that double transgenic NOD.Ins-IL-10-D(d) mice developed accelerated diabetes in a fashion similar to NOD.Ins-IL-10 mice that were D(d) negative. Microsatellite analysis of H-2D(d)-linked loci confirmed association between BALB/c-derived alleles and protection of NOD.Ins-IL-10(H-2(g7/d)) mice. These results suggest a control of H-2D(d)-linked gene(s) on IL-10-mediated acceleration of autoimmune diabetes and dominant protection of the D(d) region in NOD.Ins-IL-10 mice.

Animals↗

PubMed2007

Decay-accelerating factor must bind both components of the complement alternative pathway C3 convertase to mediate efficient decay.

Decay-accelerating factor (DAF; CD55) inhibits the complement (C) cascade by dissociating the multimolecular C3 convertase enzymes central to amplification. We have previously demonstrated using surface plasmon resonance (Biacore International) that DAF mediates decay of the alternative pathway C3 convertase, C3bBb, but not of the inactive proenzyme, C3bB, and have shown that the major site of interaction is with the larger cleavage subunit factor B (Bb) subunit. In this study, we dissect these interactions and demonstrate that the second short consensus repeat (SCR) domain of DAF (SCR2) interacts only with Bb, whereas SCR4 interacts with C3b. Despite earlier studies that found SCR3 to be critical to DAF activity, we find that SCR3 does not directly interact with either subunit. Furthermore, we demonstrate that properdin, a positive regulator of the alternative pathway, does not directly interact with DAF. Extending from studies of binding to decay-accelerating activity, we show that truncated forms of DAF consisting of SCRs 2 and 3 bind the convertase stably via SCR2-Bb interactions but have little functional activity. In contrast, an SCR34 construct mediates decay acceleration, presumably due to SCR4-C3b interactions demonstrated above, because SCR3 alone has no binding or functional effect. We propose that DAF interacts with C3bBb through major sites in SCR2 and SCR4. Binding to Bb via SCR2 increases avidity of binding, concentrating DAF on the active convertase, whereas more transient interactions through SCR4 with C3b directly mediate decay acceleration. These data provide new insights into the mechanisms involved in C3 convertase decay by DAF.

Biological Assay↗

PubMed2003

Combined treatment with methylphenidate and citalopram for accelerated response in the elderly: an open trial.

BACKGROUND: Accelerated antidepressant treatment response may be particularly beneficial for older patients, yet there are few data to inform clinical practice. We evaluated the potential of methylphenidate to accelerate antidepressant response to citalopram and the safety and tolerability of the combined treatment in patients with geriatric major depressive disorder. METHOD: We studied 11 elderly outpatients aged 70 years and older who were diagnosed with DSM-IV major depressive disorder in a 10-week, open-label, structured trial (July 2001-July 2002). Methylphenidate was tapered and discontinued during weeks 9 and 10. Response was defined as a Hamilton Rating Scale for Depression (HAM-D) score of less than 10. The daily dose of citalopram ranged between 20 and 40 mg, and the daily dose of methylphenidate ranged between 5 and 20 mg. RESULTS: Nine patients completed the study. Six patients met criteria for accelerated response (HAM-D score < 10 and Clinical Global Impressions-Improvement scale score of 1 or 2 by treatment day 14), and 2 more patients responded by week 3. One patient was a nonresponder. The mean (SD) citalopram dose for all subjects was 27.5 (10.3) mg and the mean (SD) methylphenidate dose was 12.2 (4.9) mg. The observed side effects were mild to moderate in severity and included sedation, nausea, anxiety, polyuria, dry mouth, and hypersalivation. CONCLUSION: Methylphenidate augmentation of citalopram may be a safe and viable strategy for accelerating antidepressant response in elderly depressed patients. The results of this open-label trial need to be confirmed in a placebo-controlled trial.

Aged↗

PubMed1999

[Plea for accelerated rehabilitation after ligament plasty of the knee by a bone-patellar tendon-bone graft].

Knee rehabilitation after ACL repair with bone-tendon-bone graft is still controversial. While there was a tendency to protect the graft and the donor site in the eighties, actual tendency is to propose more aggressive, so called accelerated rehabilitation protocol. An extensive analysis of the literature shows that this accelerated rehabilitation is justified because of histologic, biomechanic, surgical and clinical arguments. This accelerated rehabilitation is based on seven reasons, at least: 1) the necrosis of the graft, initially observed in animals, does not seem to be as important in humans as demonstrated by histological studies after in vivo biopsies; 2) the use of solid bone-tendon-bone graft, whose resistance is maximum in the early post-operative period and is superior to the resistance of the ACL; 3) the more precise positioning (more "isometric") because of optic magnification allowed by arthroscopy; 4) the absence of graft impingement, routinely controlled, because of a more posterior tibial placement of the graft and the eventual notch-plasty; 5) the solid and confident fixation of the graft because of interference screws; 6) anterior knee pain are less important when early constraints are applied on the knee; 7) finally, undisciplined and demanding patients who refuse all protection for the graft and the donor site, have good and stable results regarding stability of the knees. Early constraints on the knee after bone-tendon-bone graft and interference fixation give better tolerance on the extension mechanism without compromising integrity of the graft and knee stability. Appropriate level of constraints on the ACL graft and the donor site guides the collagenic reorganisation process. Early restoration of normal hyperextension, decreased knee pain and maintenance of muscular trophicity, allowing patients to go back to sport at 4 months, are the most evident benefits of this accelerated rehabilitation. These considerations cannot be applied to the other grafts (fascia lata, semi-tendinous, allografts ...) and to other ways of fixation (sutures, staples, ...).

Animals↗

PubMedDate not supplied

Accelerated streptokinase--a new thrombolytic regimen in acute myocardial infarction.

Efficiency and safety of an accelerated regimen of streptokinase (1.5 M.U. over 20 min., 109 patients) has been compared with the standard regimen (1.5 M.U. over 60 min, 119 patients) in 218 patients admitted within the first 6 hours after the onset of the symptoms of acute myocardial infarction. Using the noninvasive criteria we found a coronary reperfusion rate of 77.04% in patients belonging to the accelerated regimen group and this value was significantly higher than the one of 57.14% registered in the standard group. No major hemorrhagic events were registered in both groups. Although the hypotension appeared to be more frequent in patients in whom the accelerated regimen was used, however this side effect proved to be transient and well controlled using the rapid infusion of natrium chloride solution. In conclusion, the accelerated regimen of streptokinase is safe and followed by a higher rate of coronary reperfusion as compared to the standard one.

Aged↗

PubMed2000

Doppler-derived acceleration rate of right ventricular early filling reliably predicts mean right atrial pressure at baseline and after loading manipulations in patients with chronic heart failure.

BACKGROUND: We investigated whether Doppler-derived variables of tricuspid flow could estimate mean right atrial pressure and monitor its changes after loading manipulations in patients with chronic heart failure. METHODS: Simultaneous mean right atrial pressure (Swan-Ganz catheterization) and tricuspid Doppler recordings were initially evaluated in 136 patients (23 with atrial fibrillation) with chronic heart failure and severe left ventricular systolic dysfunction, and then were repeated in 18 patients after unloading (sodium nitroprusside infusion) and in 13 patients after overloading (active leg elevation) manipulations. RESULTS: A significant correlation was observed between mean right atrial pressure and peak E velocity (r = 0.70), early deceleration time (r = -0.72) and acceleration time (r = -0.75). However, the best correlation found was between the acceleration rate of early flow and mean right atrial pressure, and it was identical in patients in sinus rhythm or with atrial fibrillation (r = 0.98). Moreover, after acute effective unloading or overloading manipulations, although all Doppler tricuspid variables changed significantly, the acceleration rate of early flow still emerged as the strongest independent predictor of mean right atrial pressure (r = 0.95 and 0.99, respectively). CONCLUSIONS: Doppler-derived acceleration rate of early diastolic tricuspid flow is a powerful tool to predict mean right atrial pressure and to monitor its changes after loading manipulations.

Adult↗