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Biomedical subjects

F Xie

Publications and source records attributed to F Xie.

At least 55 records · Page 3Linked to original sources
PubMed2001

[Quantitative structure and activity relationship for epoxides].

Mutagenic activity data of 86 epoxides were collected from a CD system of Registry of Toxic Effects of Chemical Substances (RTECS 1998 Version). By using principal component analysis, the 5 kinds from 11 kinds of molecular structure descriptors, such as the number of carbon atom, the number of benzene-cycle, the number of hydrogen atom, the number of substituted alkyl group and the number of oxygen atom which can have influence on their mutagenic activity very much were chosen. After learning of above samples. The Back-Propagation Method(BP) network structure was optimized, the learning sets of sample were classified, then unknown samples were predicted one by one; for 86 samples, the correctly classified rate can reach to 92% between the low class and the high class. Results shown that the special molecular structure, the epoxides of polycyclic aromatic hydrocarbons contained 3-4 cycles, can be responsible for their very high mutagenic activities.

Epoxy Compounds↗
PubMed2001

[Secondary metabolites of Gliocladium sp., a growth accelerating fungus for Anoectochilus roxburghii (Wall.) Lindl].

OBJECTIVE: To study the secondary metabolites of fungus Gliocladium sp. that helps accelerate the growth of A. roxburghii. METHOD: Compoud isolation by chromatography and structure elucidation by chemical and spectral analyses. RESULTS: Five compounds were obtained and elucidated as: 8(E)-N-(2'-hydroxypalmityl)-1-O-beta-gly-copyranosyl-3-hydroxyl-9-methyl-2- octodecanine-4, 8-diene (I), N-(2'-hydroxytetracosanoyl)-1,3,4-trihydroxy-2-octodecanine(II), 7, 22-diene-3-hydroxy-6,9-epidioxyergosta(III), ergostol(IV) and alpha-palmitin(V). CONCLUSION: I, II, III were obtained from Gliocladium sp. for the first time.

Ceramides↗
PubMed2001

Comparative experimental study of Ho-Yag laser and true-cut biopsy needle in myocardial revascularization.

OBJECTIVE: To study the mechanism and effects of blood perfusion on acute ischemic region of myocardium through channel created by Ho-Yag laser and True-cut biopsy needles with myocardial contrast echocardiography. METHODS: We partially ligated the left anterior descending coronary artery of canine hearts between the 1st and 2nd diagonal branches to produce two groups of acute myocardial ischemia models and then performed transmyocardial revascularization (TMR) on this region with Ho-Yag laser and True-cut biopsy needles. Myocardial contrast echocardiography was performed with a new generation of ultrasound contrast agent and second harmonic imaging of this region before, during ischemia and after revascularization. Pictures were taken with "R" wave trigger skill. RESULTS: Acoustic density (dB) in the ischemic region (anterior wall) with myocardial contrast echocardiography decreased obviously after the left anterior descending artery was ligated (Laser group: 5, 40 +/- 1.81, Needle group: 7.11 +/- 2.51) compared with that before (Laser group: 11.69 +/- 1.61, Needle group: 12.96 +/- 2.88, P < 0.01). dB increased remarkably after TMR by either laser or True-cut biopsy needle (Laser group: 11.02 +/- 2.01, Needle group: 10.01 +/- 4.45. P < 0.01) compared to that during ischemia and approximated to that before ischemia (P > 0.05). We found that the acoustic density of the contrast developed one picture (one cardiac cycle) ahead in the transmyocardial revascularization region than that in the lateral and other region of the left ventricle wall in the scan of both groups. CONCLUSIONS: Acute ischemic myocardium can be perfused immediately by oxygenated blood from the left ventricle through channels created with both Ho-Yag laser and True-cut biopsy needles. Evidence of blood perfusion through these channels mainly during systolic phase was detected, and myocardial contrast ultrasound using intravenous perfluorocarbon-exposed sonicated dextrose albumin was regarded as a reliable method in the study of transmyocardial revascularization.

Animals↗
PubMed2000

Measuring fig quality using near-infrared spectroscopy.

Sorting of dried figs prior to inspection is labor-intensive and somewhat complex. We examined the potential of using near-infrared spectroscopy (NIRS) to automate sorting of dried figs. Calimyrna and Adriatic types were inspected by hand using established criteria. For both varieties, approximately 100 passable figs and 100 figs each for the infested, rotten, sour, and dirty defect categories were examined using NIRS and partial least-squares regression (PLS). Correct classifications for these varieties ranged from 83 to 100%. About twenty PLS factors were used to make the predictions. These results indicate that the use of NIRS to help automate inspection for dried fig processing is feasible. However, the large number of wavelengths needed for prediction, as indicated by PLS beta coefficients, indicates that implementing NIRS in fig sorting may require an instrument capable of reading numerous wavelengths rather than a more economical filter-based instrument.

Journal Article↗
PubMed2000

A novel mutation in the NADH-cytochrome b5 reductase gene of a Chinese patient with recessive congenital methemoglobinemia.

Recessive congenital methemoglobinemia due to nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase (b5R) deficiency is classified into 2 clinical types: type 1 (erythrocyte type) and type 2 (generalized type). We found a Chinese family with type 1 recessive congenital methemoglobinemia, the patients from which were diagnosed according to clinical symptoms and b5R enzyme activity in the blood cells. To learn the molecular basis of type 1 recessive congenital methemoglobinemia in this Chinese family, we isolated total RNA from the peripheral leukocytes of the propositus and b5R complementary DNA (cDNA) by reverse transcription- polymerase chain reaction (RT-PCR). The coding region of the b5R cDNA was analyzed by sequencing the cloned PCR products. The results showed that the propositus was homozygous for a G-->A transition at codon 203 in exon 7, changing a cysteine to a tyrosine (Cys203Tyr). To characterize the mutant enzyme, both glutathione S-transferase (GST)-fused wild-type b5R and GST-fused mutant Cys203Tyr b5R were expressed in Escherichia coli and affinity purified. The results showed that the catalytic activity of the enzyme was not much affected by this amino acid substitution, but the mutant enzyme exhibited decreased heat stability and increased susceptibility to trypsin. These properties of the mutant enzyme would account for the restricted b5R deficiency and mild clinical manifestations of these type 1 patients. The finding of this novel mutation makes codon 203 the only position within the b5R gene at which more than 1 mutation has been found.

Aged↗
PubMed2000

Detection of angiographically significant coronary artery disease with accelerated intermittent imaging after intravenous administration of ultrasound contrast material.

BACKGROUND: Accelerated intermittent harmonic imaging (AII) is used to detect myocardial perfusion abnormalities after intravenous injection of ultrasound contrast medium. A low mechanical index and frame rates of 10 to 20 Hz are used to allow simultaneous wall motion analysis. The purpose of this study was to determine whether the myocardial contrast enhancement achieved with AII can be used to detect angiographically significant coronary artery disease during stress echocardiography. METHODS: We gave intravenous perfluorocarbon containing microbubbles to 45 patients (total of 270 regions) during dobutamine (n = 27) or exercise (n = 18) stress testing with AII. Quantitative angiography was performed on all patients after the stress echocardiograms were interpreted. RESULTS: Quantitative angiography showed >50% diameter stenosis of at least 1 vessel in 32 patients (total of 118 regions). There were visually evident contrast defects in 100 (85%) of these regions, and wall motion was abnormal in 64 (54%). Overall, there was agreement between regional perfusion and quantitative angiographic findings in 217 of the 270 regions (kappa = 0.61; 80% agreement). Agreement with findings at quantitative angiography was good for both dobutamine stress (kappa = 0.66; 83% agreement) and exercise (kappa = 0.53; 77% agreement). The greatest incremental benefit of AII versus wall motion was gained during dobutamine stress. The contrast studies depicted 90% of the regions supplied by a vessel with >50% stenosis, whereas wall motion depicted only 32% (P =.001). CONCLUSIONS: The results of this study indicated that accelerated intermittent perfusion imaging during stress echocardiography can improve the sensitivity of the study in detecting angiographically significant coronary artery disease, especially during dobutamine stress.

Adult↗
PubMed2000

Scroll wave dynamics in a three-dimensional cardiac tissue model: roles of restitution, thickness, and fiber rotation.

Scroll wave (vortex) breakup is hypothesized to underlie ventricular fibrillation, the leading cause of sudden cardiac death. We simulated scroll wave behaviors in a three-dimensional cardiac tissue model, using phase I of the Luo-Rudy (LR1) action potential model. The effects of action potential duration (APD) restitution, tissue thickness, filament twist, and fiber rotation were studied. We found that APD restitution is the major determinant of scroll wave behavior and that instabilities arising from APD restitution are the main determinants of scroll wave breakup in this cardiac model. We did not see a "thickness-induced instability" in the LR1 model, but a minimum thickness is required for scroll breakup in the presence of fiber rotation. The major effect of fiber rotation is to maintain twist in a scroll wave, promoting filament bending and thus scroll breakup. In addition, fiber rotation induces curvature in the scroll wave, which weakens conduction and further facilitates wave break.

Action Potentials↗
PubMed2000

Origins of spiral wave meander and breakup in a two-dimensional cardiac tissue model.

We studied the stability of spiral waves in homogeneous two-dimensional cardiac tissue using phase I of the Luo-Rudy ventricular action potential model. By changing the conductance and the relaxation time constants of the ion channels, various spiral wave phenotypes, including stable, quasiperiodically meandering, chaotically meandering, and breakup were observed. Stable and quasiperiodically meandering spiral waves occurred when the slope of action potential duration (APD) restitution was < 1 over all diastolic intervals visited during reentry; chaotic meander and spiral wave breakup occurred when the slope of APD restitution exceeded 1. Curvature of the wave changes both conduction velocity and APD, and their restitution properties, thereby modulating local stability in a spiral wave, resulting in distinct spiral wave phenotypes. In the LRI model, quasiperiodic meander is most sensitive to the Na+ current, whereas chaotic meander and breakup are more dependent on the Ca2+ and K+ currents.

Action Potentials↗
PubMed2000

Involvement of the Ca(2+)-protein kinase C and adenyilate cyclace signal pathways in the activation of thymocytes in response to whole-body irradiation with low dose X-rays.

OBJECTIVE: To study the molecular mechanism of the stimulatory effect of low dose radiation (LDR) on T cell activation. METHODS: Thymocytes from Kunming mice exposed to whole-body irradiation (WBI) with different doses of X-rays were analyzed for the changes in signal molecules of the phospholipase C-phosphatidylinositol biphosphate (PLC-IP2) and G protein-adenylate cyclase (AC) pathways. RESULTS: It was found that [Ca2+]i increased in response to doses within 0. 2 Gy which was most marked after 0. 075 Gy and the increase was accentuated in the presence of Con A. The changes in CD3 and calcineurin (CN) expression of the thymocytes followed the same pattern as the alterations in [Ca2+]i after LDR. The expression of alpha, beta1 and beta2 isoforms of protein kinase C (PKC) was all up-regulated after 0.075 Gy with the increase in PKC-beta1 expression being most marked. The cAMP/cGMP ratio and PKA activity of the thymocytes was lowered after low dose radiation and increased after doses above 0. 5 Gy in a dose-dependent manner, thus giving rise to J-shaped dose-response curves. The Ca antagonist TMB-8 and cAMP stimulant cholera toxin suppressed the augmented thymocyte proliferation induced by LDR. CONCLUSION: Data presented in the present paper suggest that activation of the PLC-PIP2 signal pathway and suppression of the AC-cAMP signal pathway are involved in the stimulation of the thymocytes following WBI with low dose X-rays.

Animals↗
PubMed2000

Experimental study of homium: YAG laser transmyocardial revascularization in acute ischemic settings with myocardial contrast echocardiography.

OBJECTIVE: To study the mechanism and effects of blood perfusion to the acute ischemic region of myocardium through Ho-YAG laser channels with myocardial contrast echocardiography. METHODS: To produce the model of acute myocardial ischemia, we partially ligated the left anterior decending (LAD) coronary artery of canine hearts between 1st. and 2nd. diagonal branches and then performed transmyocardial revascularization in this region with Ho - YAG laser. Myocardial contrast echocardiography was made with a new generation of ultrasound contrast agent and second harmonic imaging of this region before, after ischemia and after laser revascularization. Pictures were taken with "R" wave trigger skill. RESULTS: Acoustic density determing in the ischemia region (anterior wall) with MCE (myocardial contrast echocardiography) was obviously decreased (5.40 +/- 1.81) after the LAD was ligated,as compared with before (11.69 +/- 1.61, P < 0.01). It was increased remarkably after transmyocardial laser revascularization (TMLR) (11.2 +/- 2.01, P < 0.01) as compared with that when ischemia and approximated to that before ischemia (P > 0.05). There were no differences in acoustic density in the lateral wall (as control) among these comprehensive three periods (P > 0.05). Contrast in the laser region developed one cardiac cycle ahead of that in the non-ischemic normal region. CONCLUSION: Acute ischemic myocardium can be perfused by oxygenated blood from the left ventricle through Ho - YAG laser channels. Evidence of blood perfusion through laser channels during systolic phase was detected, and myocardial contrast ultrasonography using intravenous perfluorocarbon-exposed sonicated dextrose albumin may be regarded as a reliable method in the study of transmyocardial revascularization.

Animals↗
PubMed2000

[Synthesis and spectroscopic studies of new N-functionalized macrocyclic compounds and complex].

Three new N-functionalized tetraazamacrocyclic compounds, C-messo-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane- N,N',N",N'"-tetrakis (ethyl acetate) (A), C-messo-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane-N,N,'N",N'"-tetraacetic acid (H4L) and the hydrobromide of H4L have been synthesized and the complex Na2[NiL].2C2H5OH has been prepared as well. The macroyclic compounds and the complex have been studied by electronic spectrum, infrared spectrum, 1H NMR, MS and elemental analysis.

English Abstract↗
PubMed1999

Role of papillary muscle in the generation and maintenance of reentry during ventricular tachycardia and fibrillation in isolated swine right ventricle.

BACKGROUND: The role of papillary muscle (PM) in the generation and maintenance of reentry is unclear. METHODS AND RESULTS: Computerized mapping (477 bipolar electrodes, 1.6-mm resolution) was performed in fibrillating right ventricles (RVs) of swine in vitro. During ventricular fibrillation (VF), reentrant wave fronts often transiently anchored to the PM. Tissue mass reduction was then performed in 10 RVs until VF converted to ventricular tachycardia (VT). In an additional 6 RVs, procainamide infusion converted VF to VT. Maps showed that 77% (34 of 44) of all VT episodes were associated with a single reentrant wave front anchored to the PM. Purkinje fiber potentials preceded the local myocardial activation, and these potentials were recorded mostly around the PM. When PM was trimmed to the level of endocardium (n = 4), sustained VT was no longer inducible. Transmembrane potential recordings (n = 5) at the PM revealed full action potential during pacing, without evidence of ischemia. Computer simulation studies confirmed the role of PM as a spiral wave anchoring site that stabilized wave conduction. CONCLUSIONS: We conclude that PM is important in the generation and maintenance of reentry during VT and VF.

Animals↗
PubMed1999

In vivo microdialysis/liquid chromatography/tandem mass spectrometry for the on-line monitoring of melatonin in rat.

Liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been coupled to in vivo microdialysis for on-line monitoring of melatonin in a freely moving rat for a period of 15 hours. A microdialysis probe was surgically implanted into the jugular vein of the rat, and deionized water was used as the perfusion medium at a flow rate of 1.0 microL/min. Microdialysis samples were collected in an on-line injector with sample injection every 30 minutes. Melatonin was dosed by intraperitoneal (i.p.) injection and then monitored by microdialysis/LC/MS/MS. The whole experiment, including the microdialysis sampling and sample injection into the LC/MS system, was fully automated. Metabolites of melatonin were identified off-line by LC/MSn experiments. Two metabolites were identified as 6-hydroxymelatonin and cyclic 2-hydroxymelatonin, consistent with ones found previously in the literature.

Animals↗
PubMed1999

Different role of antioxidants in endotoxin-induced late myocardial protection.

Previous studies have proposed that endogenous antioxidants play a protective role against cardiac ischemia-reperfusion injury in endotoxin pretreatment. However, the mechanism underlying this effect remains elusive. We therefore evaluated the role of endogenous antioxidants in delayed myocardial protection after different doses of endotoxin administration using cultured rat neonatal cardiomyocytes. Myocytes were treated with normal saline (control) or lipopolysaccharide (Escherichia coli, serotype O111) at doses of 40 and 80 microg/ml (ET40 and ET80). Also, antisense oligodeoxyribonucleotide (1.5 micromol/L) to manganese superoxide dismutase (Mn-SOD) and 3-amino-1,2,4-triazole (25 mg/ml) were added along with a 40 or 80 microg/ml endotoxin pretreatment in the IET40 and IET80 groups. Twenty-four hours later, Cells were subjected to hypoxia (pO2 < 1 kPa, 3 h) and reoxygenation (pO2: 19 kPa, 1 h). Compared with controls, cell viability enhanced significantly (65.3 +/- 5.9, 63.8 +/- 4.6, and 69.7 +/- 5.2% vs 47.2 +/- 4.3%, P < 0.05) and creatine kinase release decreased (7.34 +/- 1.76, 7.11 +/- 1.49, and 6.27 +/- 1.24 U/mg protein vs 11.23 +/- 2.49 U/mg protein, P < 0. 05) in ET40, IET40, and ET80 groups following reoxygenation. No statistically significant difference was found between the control and the IET80 groups. Furthermore, the levels of Mn-SOD (1.12 +/- 0. 31 vs 0.75 +/- 0.15 U/mg. protein, P < 0.05) and catalase activity (1265 +/- 109 vs 996 +/- 85 U/mg. protein, P < 0.05) were higher only in the ET80 group. The results suggest that at a dose of 40 microg/ml, cells were protected by mechanisms other than the augmentation of endogenous antioxidant activity which were more evident at a dose of 80 microg/ml. It seems that different doses of endotoxin pretreatment may induce delayed myocardial protection through various mechanisms.

Animals↗
PubMed1999

Effect of transducer standoff on the detection, spatial extent, and quantification of myocardial contrast defects caused by coronary stenoses.

Intermittent harmonic imaging during a continuous infusion of microbubbles may be able to quantify myocardial perfusion abnormalities. Measurements of the spatial extent of these perfusion abnormalities depends on homogenous destruction of the microbubbles in the elevation plane of the transducer. We hypothesized that uneven microbubble destruction caused by attenuation of beam intensity could alter quantitative measurements of perfusion abnormalities during stress. To test this hypothesis, we measured the spatial extent of perfusion defects at peak dobutamine stress with a continuous intravenous infusion of perfluorocarbon-exposed sonicated dextrose albumin and intermittent harmonic imaging in dogs with nonflow-limiting coronary stenoses in the left anterior descending artery. The spatial extent of perfusion defects was also measured during total occlusion of the artery. Measurements were made at standoffs of 2- to 3-cm and 4- to 5-cm distance from transducer surface to myocardium. These spatial extents were correlated with risk area determined after death. The risk area during left anterior descending occlusion at a standoff of 2 to 3 cm was significantly larger at a 1500-ms pulsing interval (6.5 +/- 2.6 cm(2) for 2- to 3-cm standoff versus 3.7 +/- 1.4 cm(2) for 4- to 5-cm standoff; P =.01). The spatial extent at the 2- to 3-cm standoff more closely approximated risk area measured with Monastral Blue (7.8 +/- 2.7 cm(2)). Myocardial perfusion abnormalities during peak dobutamine stress were significantly smaller with the 4- to 5-cm standoff and undetectable in 4 of the 5 dogs. We conclude that ultrasound beam attenuation can reduce the size of a myocardial perfusion abnormality observed with intermittent harmonic imaging during a continuous infusion of microbubbles. This may reduce the sensitivity of this technique when transthoracic imaging is used.

Albumins↗
PubMed1999

An evaluation of the safety and immunogenicity of a five-component acellular pertussis, diphtheria, and tetanus toxoid vaccine (DTaP) when combined with a Haemophilus influenzae type b-tetanus toxoid conjugate vaccine (PRP-T) in Taiwanese infants.

OBJECTIVE: Immunologic interference particular to the Haemophilus influenzae type b (Hib) response has been observed with previous acellular pertussis-Hib combination vaccines. To test this hypothesis a clinical trial to assess the safety and immunogenicity of a five-component (pertussis toxoid [PT], filamentous hemagglutinin [FHA], pertactin [PRN], and fimbriae 2 and 3 [FIM]), pertussis vaccine combined with diphtheria and tetanus toxoids (DTaP) when given simultaneously with a lyophilized Hib-tetanus toxoid conjugate vaccine (PRP-T) in infants at 2, 4, 6, and 18 months of age was conducted. The study compared two methods of administration: both vaccines combined in a single syringe and administered as a single injection, or both vaccines administered concurrently but at separate sites of injection. METHODS: Healthy 2-month-old infants were enrolled at the National Taiwan University Hospital. DTaP, PRP-T, and oral poliomyelitis vaccine (OPV) were given at 2, 4, 6, and 18 months. Reaction information was collected by telephone 2 days after each vaccination. Serum was collected at 2, 6, 7, 18, and 19 months of age. RESULTS: One hundred thirty-five healthy infants were enrolled in Taiwan, of which 127 (94%) completed the 18-month booster: 68 received the combined vaccine and 67 the separate vaccines. All vaccines were well tolerated. No differences in rates of local and systemic reactions were seen between the two methods of administration. No serious adverse events were reported. Serologic responses were comparable between the groups. Pertussis responses (enzyme-liked immunoabsorbant assay units [EU]/mL) at 7 months were, for combined versus separate, PT (131 vs 105), FHA (116 vs 116), PRN (100 vs 77), and FIM (922 vs 702). At 19 months, pertussis results were, for combined versus separate, PT (216 vs 182), FHA (203 vs 200), PRN (263 vs 197), and FIM (892 vs 732). Only the 7-month PT response in the combined group was significantly higher (combined 131 EU/mL vs separate 105 EU/mL). After the third dose (age 6 months), all subjects achieved serologic serum antibody levels indicative of protection against Hib, diphtheria, tetanus, and poliovirus types 1, 2, and 3. In fact, 96% of children had anti-PRP levels indicative of protection (>/=0.15 microgram/mL) against Hib after only two doses. At 7 months, anti-PRP geometric mean titer values were 11.8 micrograms/mL in the combined group compared with 13.0 micrograms/mL in the separate group. The anti-PRP geometric mean titers after the 18-month booster were 58.5 micrograms/mL in the combined group versus 55.3 micrograms/mL in the separate group. CONCLUSION: The five-component DTaP vaccine may be combined with PRP-T vaccine without clinically significant immunologic interaction when given in a 2-, 4-, 6-, and 18-month schedule.

Diphtheria↗
PubMed1998

Role of pectinate muscle bundles in the generation and maintenance of intra-atrial reentry: potential implications for the mechanism of conversion between atrial fibrillation and atrial flutter.

To determine the role of pectinate muscle (PM) bundles in the formation of intra-atrial reentry, 10 isolated canine right atrial tissues were perfused with Tyrode's solution containing 1 to 2.5 micromol/L acetylcholine (ACh). The endocardium was mapped using 477 bipolar electrodes with 1.6-mm resolution. Reentry was induced by a premature stimulus (S2). Computer simulation studies were used to investigate the importance of regional myocardial thickness in reentry formation. A total of 40 episodes of reentry were induced; 28 episodes were stationary, and the remaining 12 were nonstationary. The stationary reentry was induced either immediately after the S2 stimuli (n=9) or after an initial period of irregular activations that lasted 1460+/-1077 ms (n= 19). Of 28 episodes, 20 were initiated by conduction block along large PM ridges, leading to wave break and the initiation of reentry. The reentrant wave fronts remained stationary and rotated around these ridges as anchoring sites. During the transition from the initial irregular activations to stationary reentry, the electrogram morphology converted from "fibrillation-like" to "flutter-like" activity. In 8 episodes, initially stationary reentry converted to irregular activations because of interference with outside wave fronts (n=5) or spontaneous separation of waves from the ridges (n=3). Compared with stationary reentry, nonstationary reentry always occurred over an area without large PMs, and the mean life span was much shorter (102+/-151 versus 3.8+/-1.1 rotations, P<0.001). Computer simulation studies showed that a critical ridge thickness is needed for reentry to anchor, thereby converting fibrillation to flutter. We conclude that PM ridge forms an area where wave break occurs, allowing the initiation of reentry. It also provides a natural anchor to the reentrant wave front, lengthening the life span of reentry. The attachment and detachment of the reentrant wave front to and from the ridge determine "flutter-like" or "fibrillation-like" activity.

Animals↗