Asymmetry in the nonmesonic weak decay of polarized (5)(Lambda)He hypernuclei

We have measured the asymmetric emission of protons from the nonmesonic decay of polarized (5)(Lambda)He produced by the (pi(+), K+) reaction. (5)(Lambda)He is an s-shell hypernucleus and its polarization is due to the Lambda. One expects to obtain direct information on the elementary weak Lambda-->p-->np process. The asymmetry parameter has been determined to be 0.24+/-0.22. The implication of the result is discussed.

Influence of aging on systolic left ventricular wall motion velocities along the long and short axes in clinically normal patients determined by pulsed tissue doppler imaging

Our objective was to evaluate the influence of aging on left ventricular (LV) regional systolic function along the long and short axes in clinically normal patients. We recorded LV wall motion velocity patterns at the mid-wall portion of the middle of the LV posterior wall in the parasternal long-axis view (short-axis direction) and at the endocardial portion of the middle of the LV posterior wall in the apical long-axis view (long-axis direction) with pulsed tissue Doppler imaging in 80 normal patients (age range 15 to 78 years). In all patients the LV pressure curve and its first derivative (dP/dt) were recorded. The systolic wave of the LV posterior wall motion velocity pattern exhibited 2 peaks, the first (Sw(1)) and second (Sw(2)) systolic waves. No significant changes were seen with aging in the percent LV fractional shortening determined by M-mode echocardiography, LV ejection fraction determined by left ventriculography, the peak Sw(1) and Sw(2) along the short axis, the peak Sw(2) along the long axis, and the peak dP/dt. The peak Sw(1) along the long axis correlated inversely with age (P <.0001) but did not correlate significantly with the peak dP/dt. These results suggest that shortening of the longitudinal fibers in early systole is impaired with increased age in healthy individuals. This impairment results in insufficient spherical change in the LV cavity, although global LV pump function and myocardial contractility are maintained.

1alpha,25-dihydroxyvitamin D(3)-26,23-lactone analogs antagonize differentiation of human leukemia cells (HL-60 cells) but not of human acute promyelocytic leukemia cells (NB4 cells)

We examined the effects of two novel 1alpha,25-dihydroxyvitamin D(3)-26,23-lactone (1alpha,25-(OH)(2)D(3)-26,23-lactone) analogs on 1alpha,25(OH)(2)D(3)-induced differentiation of human leukemia HL-60 cells thought to be mediated by the genomic action of 1alpha, 25-dihydroxyvitamin D(3) (1alpha,25-(OH)(2)D(3)) and of acute promyelocytic leukemia NB4 cells thought to be mediated by non-genomic actions of 1alpha,25-(OH)(2)D(3). We found that the 1alpha,25-(OH)(2)D(3)-26,23-lactone analogs, (23S)-25-dehydro-1alpha-hydroxyvitamin D(3)-26,23-lactone (TEI-9647) and (23R)-25-dehydro-1alpha-hydroxyvitamin D(3)-26,23-lactone (TEI-9648), inhibited differentiation of HL-60 cells induced by 1alpha,25-(OH)(2)D(3). However, 1beta-hydroxyl diastereomers of these analogs, i.e. (23S)-25-dehydro-1beta-hydroxyvitamin D(3)-26, 23-lactone (1beta-TEI-9647) and (23R)-25-dehydro-1beta-hydroxyvitamin D(3)-26,23-lactone (1beta-TEI-9648), did not inhibit differentiation of HL-60 cells caused by 1alpha,25-(OH)(2)D(3). A separate study showed that the nuclear vitamin D receptor (VDR) binding affinities of the 1-hydroxyl diastereomers were about 200 and 90 times weaker than that of 1alpha-hydroxyl diastereomers, respectively. Moreover, none of these lactone analogs inhibited NB4 cell differentiation induced by 1alpha,25-(OH)(2)D(3). In contrast, 1beta,25-dihydroxyvitamin D(3) (1beta,25-(OH)(2)D(3)) and 1beta,24R-dihydroxyvitamin D(3) (1beta,24R-(OH)(2)D(3)) inhibited NB4 cell differentiation but not HL-60 cell differentiation. Collectively, the results suggested that 1-hydroxyl lactone analogs, i.e. TEI-9647 and TEI-9648, are antagonists of 1alpha,25-(OH)(2)D(3), specifically for the nuclear VDR-mediated genomic actions, but not for non-genomic actions.

Cyclic variation of thickness in an age-related thick mitral valve observed by transthoracic echocardiography

The cyclic variation of thickness during the cardiac cycle in age-related degenerative mitral valve (MV) has not been reported. Transthoracic echocardiography was used to evaluate the cyclic alteration in MV thickness in 40 patients with age-related MV thickening (diastolic MV thickness > or = 4 mm, age 70 +/- 14 years), 10 with mitral valve prolapse (MVP, age 49 +/- 11 years), 10 with rheumatic mitral stenosis (MS, age 66 +/- 9 years), and 31 control subjects (diastolic MV thickness < or = 3.6 mm, 53 +/- 17 years). After determination of the site of maximal thickness during diastole, the maximal and minimal thickness during systole of the anterior MV were measured. The percent change in MV thickness from diastole to systole (%deltaT) was calculated. The mitral regurgitation (MR) area was measured on color Doppler echocardiogram. The %deltaT (mean +/- sd) in age-related thickened MV and MVP groups were similar and significantly greater than that in control (60 +/- 8%, 61 +/- 6% vs 32 +/- 9%, p < 0.001). MR area was significantly greater in the age-related thickened MV group than that in controls (160 +/- 205 mm2 vs 14 +/- 40 mm2, p < 0.05). The %deltaT in MS (10 +/- 6%) was smallest (p < 0.001). A large cyclic alteration in valvular thickness was observed in the age-related degeneration of the MV and may be the cause of large MR despite no leaflet prolapse. The echocardiographic assessment of cyclic variation of MV thickness is feasible for estimating the histologic damage in thick MV.

Subclinical portal-systemic encephalopathy in a child with congenital absence of the portal vein

A 6-year-old girl with congenital absence of the portal vein (CAPV) who had persistent hyperammonemia due to a congenital portosystemic shunt is reported. The patient only exhibited mild intention tremor, without any apparent neurological manifestations of portal-systemic encephalopathy. However, magnetic resonance imaging of the head showed white matter atrophy with ventricular dilatation, which is thought to represent subclinical brain damage caused by chronic hyperammonemia. This is the first report of subclinical portal-systemic encephalopathy in a patient with CAPV. The present case suggests that the effect of a congenital portosystemic shunt on the central nervous system is serious, but can be clinically latent in children with CAPV.

Idiopathic small-fiber sensory neuropathy in childhood: A diagnosis based on objective findings on punch skin biopsy specimens

Idiopathic small-fiber sensory neuropathy (SFSN) has not previously been reported in children. Although affected patients complain of neuropathic pain, this condition is often difficult to diagnose because of the few objective physical signs and normal nerve conduction studies. We report a girl with idiopathic SFSN in whom the results of a sural nerve biopsy were normal, but punch skin biopsy revealed reduced intraepidermal nerve fiber density and established the diagnosis. Idiopathic SFSN should be considered in the differential diagnosis of children who have burning limb pain with no routine electrophysiologic or pathologic abnormalities.

Antagonistic action of novel 1alpha,25-dihydroxyvitamin D3-26, 23-lactone analogs on differentiation of human leukemia cells (HL-60) induced by 1alpha,25-dihydroxyvitamin D3

We examined the effects of two novel 1alpha,25-dihydroxyvitamin D3-26,23-lactone (1alpha,25-lactone) analogues on human promyelocytic leukemia cell (HL-60) differentiation using the evaluation system of the vitamin D nuclear receptor (VDR)/vitamin D-responsive element (DRE)-mediated genomic action stimulated by 1alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3) and its analogues. We found that the 1alpha,25-lactone analogues (23S)-25-dehydro-1alpha-hydroxyvitamin-D3-26,23-lactone (TEI-9647), and (23R)-25-dehydro-1alpha-hydroxyvitamin-D3-26,23-lactone (TEI-9648) bound much more strongly to the VDR than the natural (23S, 25R)-1alpha,25(OH)2D3-26,23-lactone, but did not induce cell differentiation even at high concentrations (10(-6) M). Intriguingly, the differentiation of HL-60 cells induced by 1alpha,25(OH)2D3 was inhibited by either TEI-9647 or TEI-9648 but not by the natural lactone. In contrast, retinoic acid or 12-O-tetradecanoylphorbol-13-acetate-induced HL-60 cell differentiation was not blocked by TEI-9647 or TEI-9648. In separate studies, TEI-9647 (10(-7) M) was found to be an effective antagonist of both 1alpha,25(OH)2D3 (10(-8) M) mediated induction of p21(WAF1, CIP1) in HL-60 cells and activation of the luciferase reporter assay in COS-7 cells transfected with cDNA containing the DRE of the rat 25(OH)D3-24-hydroxylase gene and cDNA of the human VDR. Collectively the results strongly suggest that our novel 1alpha,25-lactone analogues, TEI-9647 and TEI-9648, are specific antagonists of 1alpha, 25(OH)2D3 action, specifically VDR/DRE-mediated genomic action. As such, they represent the first examples of antagonists, which act on the nuclear VDR.

Spontaneous regression of hepatocellular carcinoma

A 62-year-old Japanese man with hepatitis B virus-related liver cirrhosis revealed alpha-fetoprotein (AFP) elevation. Dynamic computed tomography, taken at this time, showed a liver tumor in the anterior segment. As the patient refused any further medical treatment, he was observed in an outpatient clinic. The size of the tumor reduced and the serum level of AFP decreased gradually without any treatment. Twelve months after the initial diagnosis, the tumor could not be detected by computed tomography (CT) scan, and the level of AFP had declined to the normal range. Blood supply is essential for tumor growth and an arterioportal shunt near the tumor may change the dynamics of blood flow to the tumor. The shunt found in this patient was thought to be one of the causative factors leading to regression, but it could not be denied that immunological mechanisms may have played an important role in the spontaneous regression of hepatocellular carcinoma.

Nonconvulsive status epilepticus in eyelid myoclonia with absences--evidence of provocation unrelated to photosensitivity

A 10-year old girl with eyelid myoclonia with absences (EMA) in whom nonconvulsive status epilepticus developed shortly after awakening is described. A video-polygraphic recording during the status showed the characteristic eye-closure provocation of eyelid myoclonia with upward deviation of the eyeballs and brief absences. Ictal EEG showed generalized polyspikes concomitant with eyelid myoclonia, while absences were accompanied by 3.5 Hz polyspike-wave complexes on EEG. This condition occurred even in total darkness as well as even after seizures precipitated by bright sunlight had been eliminated by medication. The present case suggests that the eye closure mechanism could be a more potent precipitating factor than photosensitivity in the pathophysiology of EMA.

Association of fatty liver with increased ratio of visceral to subcutaneous adipose tissue in obese men

We studied the association of fatty liver with subcutaneous and visceral obesity in 46 male and 36 female patients with body mass index (BMI) over 22 kg/m2. The correlation coefficient between the ratio of the visceral adipose tissue to the subcutaneous adipose tissue (V/S) and the computed tomography (CT) number of the liver was -0.299 (P < 0.05) and that between the V/S ratio and the ratio of the CT number of the liver to that of the spleen (CT-L/CT-S) was -0.335 (P < 0.05) in the males. Partial correlation analysis after making correction for BMI showed an increased correlation coefficient of -0.485 (P < 0.05) between the V/S ratio and the CT-L/CT-S ratio in the males. The odds ratio in the males for CT-L/CT-S below 1.0 and V/S above 1.0 was 3.25 with a 95% confidence interval of 1.02 to 9.39. No such association between the V/S ratio and the CT-L/CT-S ratio was present in the female patients. Multiple regression analysis with serum level of alanine aminotransferase, a marker of fatty liver, as an independent variable revealed a partial regression coefficient of -17.7 for CT-L/CT-S (P < 0.05) in the males and -21.7 (P < 0.05) in the females, validating the CT-L/CT-S ratio as an index of fatty liver. The results indicate the association of fatty liver as determined by the CT-L/CT-S ratio with visceral obesity in males.

Difference in systolic motion velocity of the left ventricular posterior wall in patients with asymmetric septal hypertrophy and prior anteroseptal myocardial infarction. Evaluation by pulsed tissue Doppler imaging

The left ventricular (LV) posterior wall in patients with asymmetric septal hypertrophy or prior anteroseptal myocardial infarction (A-MI) frequently demonstrates normal or supernormal motion to compensate for hypokinesis of the interventricular septum. This study evaluated the systolic motion velocity of the posterior wall in these conditions using a pulsed tissue Doppler imaging system. The study population consisted of 30 patients with hypertrophic cardiomyopathy (HC) and asymmetric septal hypertrophy, 25 with prior A-MI and 30 normal controls. The systolic excursion of the posterior wall was obtained by M-mode echocardiography. The endocardial motion velocities of the posterior wall were obtained by pulsed tissue Doppler imaging. The systolic excursion of the posterior wall was significantly greater in the A-MI and HC groups than in the control group, and was significantly greater in the A-MI group than in the HC group. The peak systolic velocity of the posterior wall was significantly lower in the HC group than in the control and A-MI groups, and the time from the electrocardiographic Q wave to the peak of the systolic wave of the posterior wall was significantly longer in the HC group than in the other groups. There were rough negative and positive correlations between the LV end-diastolic pressure and the peak systolic velocity and time from the Q wave to the peak of the systolic wave, respectively. In conclusion, LV myocardial contractility in HC patients was impaired when compared to A-MI patients despite similar posterior wall motion on the M-mode echocardiogram. Pulsed tissue Doppler imaging method may provide new insights and allow further evaluation of myocardial dysfunction.

[The effect of hepatic arterial infusion chemotherapy on the prognosis after hepatectomy for hepatocellular carcinoma]

The effect of hepatic arterial infusion chemotherapy on the prognosis after hepatectomy for hepatocellular carcinoma was investigated in patients with risk factors for recurrence. The risk factors for recurrence after hepatectomy were defined to be metastasis in the liver (+), portal tumor embolus (+), and tumor larger than 5 cm in diameter. Out of 87 patients with hepatocellular carcinoma who underwent an operation in the past 7 years in our hospital, 60 survived for more than 1 year and were enrolled in our study. Thirty-eight of them showed one or more risk factors for recurrence, and were considered to be the high-risk group. These 38 patients were divided into two groups: one group of 19 treated by hepatic arterial infusion chemotherapy using mitoxantrone, and the other group of 19 given no treatment. The survival rates and non-recurrence rates were compared between the two groups. The survival rates after 1 and 3 years for the group treated by hepatic arterial infusion chemotherapy were 94.7% and 54.7%, respectively. The survival rates for the non-treated group were 53.9% and 32.8%, respectively (p = 0.012). The non-recurrence rates after 1 year and 3 years were 94.7% and 44.2% for the treated group and 52.6% and 23.6% for the non-treated group (p = 0.005), respectively. The survival rates and non-recurrence rates after 3 years in the treated group were significantly higher (p = 0.012, 0.005), respectively. It was concluded, therefore, that post-operation hepatic arterial infusion chemotherapy improved the prognosis of the high-recurrence probability group.

Morphological analysis of cat masseteric motoneurons after intracellular staining with horseradish peroxidase

Intracellular injection of horseradish peroxidase (HRP) into 58 masseteric motoneurons identified by antidromic activation was performed in cats under pentobarbital anesthesia. Monosynaptic EPSPs were evoked by masseteric nerve stimuli in 52 cells, and were absent in the remaining six cells. The antidromic nature of the evoked spikes was confirmed by IS-SD separation observed at high frequency (50 Hz) stimulation. Motoneurons with monosynaptic excitation from masseter afferents showed IPSPs following stimulation of lingual and inferior alveolar nerves. Motoneurons which did not show monosynaptic excitation from masseter afferents showed no IPSPs from the above nerves. There were no differences in cell size or the number of stem dendrites between motoneurons with and without monosynaptic EPSPs. No recurrent collaterals were observed in any motor axons. Motoneurons with monosynaptic EPSPs were located at all rostrocaudal levels throughout the trigeminal motor nucleus, whereas motoneurons without such EPSPs were encountered only at the middle level. Dendrites of motoneurons with monosynaptic EPSPs did not extend into the medial portion of the nucleus where motoneurons innervating the anterior belly of the digastric muscle were located. In contrast, motoneurons without monosynaptic EPSPs had dendrite branches extending well into the medial part. The results show that there are two subpopulations of masseteric motoneurons that differ in peripheral inputs as well as dendritic morphology.

Control of vocal intensity in budgerigars (Melopsittacus undulatus): differential reinforcement of vocal intensity and the Lombard effect

Call production in budgerigars was studied using operant conditioning. In several experiments, budgerigars were reinforced with food for producing calls that were above or below a criterion level of intensity. This differential reinforcement procedure was successful in controlling vocal intensity in both directions showing that the intensity with which budgerigars produce vocalizations is under voluntary control. In additional experiments, call intensity maintained by food reinforcement was measured both in the quiet and in the presence of various levels of broadband noise. Call intensity in budgerigars increased significantly in noise, paralleling the well-known Lombard effect in humans which is the reflexive increase in speech intensity during communication in noise. Call intensity was measured in broadband noise and in a notched noise (no energy between 1.5 and 4.5 kHz) with the same overall level. Results show that noise in the spectral region of contact calls is most effective in causing an increase in vocal intensity. In aggregate, these experiments show that budgerigars have voluntary control over the intensive aspect of their vocalizations, that they normally monitor their vocal output though external auditory feedback, and, like humans, they exhibit the Lombard effect.

Recovery of hearing and vocal behavior after hair-cell regeneration

Postmitotic hair-cell regeneration in the inner ear of birds provides an opportunity to study the effect of renewed auditory input on auditory perception, vocal production, and vocal learning in a vertebrate. We used behavioral conditioning to test both perception and vocal production in a small Australian parrot, the budgerigar. Results show that both auditory perception and vocal production are disrupted when hair cells are damaged or lost but that these behaviors return to near normal over time. Precision in vocal production completely recovers well before recovery of full auditory function. These results may have particular relevance for understanding the relation between hearing loss and human speech production especially where there is consideration of an auditory prosthetic device. The present results show, at least for a bird, that even limited recovery of auditory input soon after deafening can support full recovery of vocal precision.

A case of acute myocardial infarction due to primary coronary dissection

A case of acute myocardial infarction associated with primary coronary dissection was followed up angiographically. A 46-year-old woman complained of chest oppression. Electrocardiogram on admission showed ST-segment elevation in V1-5. Urgent coronary angiography was performed under a diagnosis of acute anterior myocardial infarction, and showed a significant stenosis with multiple filling defects in segments 7-8 (99% with severe delay) in the left anterior descending artery. There was no organic lesion in the right coronary artery. Intracoronary thrombolytic therapy was unsuccessful, and thereafter she was treated with aspirin, warfarin and isosorbide dinitrate. Coronary angiography performed 1 month later revealed a long dissection with double lumens in segments 7-8. The septal branches emerged from the smaller lumen. Two months later, the 2 lumens were almost equal in size. These findings indicated that coronary dissection produced a false lumen with an entry in segment 7 and a reentry in segment 8, and that the false lumen was responsible for the greater flow. Four months later, the flow in the true lumen had improved remarkably while that in the false lumen had almost disappeared. She remained in stable condition during the follow-up period of 4 months.

Transesophageal echocardiographic prediction of initially successful electrical cardioversion of isolated atrial fibrillation. Effects of left atrial appendage function

Left atrial appendage (LAA) flow velocities prior to electrical cardioversion were recorded using transesophageal pulsed Doppler echocardiography to predict initially successful cardioversion of isolated atrial fibrillation (AF). Patients with AF were placed into either a success group (19 patients) in which sinus rhythm was maintained for at least 2 days or a failure group (12 patients). The duration of AF was shorter in the success group. The maximum left atrial diameter was the same for the two groups. The maximum LAA area was smaller in the success group. The maximum forward and backward LAA velocities were greater in the success group, as were the mean forward and backward LAA velocities. In the patients with mean LAA flow velocities greater than 19 cm/sec, the success of cardioversion could be predicted with high sensitivity (80%) and specificity (88%). We conclude that the duration of AF, the maximum LAA area, and LAA flow velocities prior to cardioversion predict the initial recovery of sinus rhythm for isolated AF.

A monoclonal antibody affects chromophore apoprotein interactions of phytochrome A

A monoclonal antibody designated Mep-1 was raised against phytochrome A from pea (Pisum sativum L.). The binding of this antibody (class IgG1) to partially degraded phytochrome (114 kDa) caused a considerable increase in the far-red peak at the red-light-induced stationary state. The effect reached a plateau value when the antibody and phytochrome were present in approximately equimolar amounts. The dark transformation of the far-red-light-absorbing form to the red-light-absorbing form of the 114 kDa phytochrome was inhibited by the addition of the antibody. However, binding of the antibody to the undegraded 121 kDa phytochrome had no effects on the spectrum of the red-light-induced steady state. The site at which the antibody bound to phytochrome was determined to be between amino acid residues 256 and 383 of pea phytochrome A. This is the first report of a monoclonal antibody that enhances the far-red absorption of phytochrome in the red-light-induced photostationary state.

Evaluation of left atrial appendage function by measurement of changes in flow velocity patterns after electrical cardioversion in patients with isolated atrial fibrillation

We investigated temporary changes in left atrial appendage (LAA) flow velocity patterns in patients undergoing electrical cardioversion for chronic isolated atrial fibrillation, and evaluated the role of active LAA contraction in directing blood flow to the left atrial main chamber and left ventricle. The study consisted of 26 patients with chronic isolated atrial fibrillation treated with electrical cardioversion and 20 normal controls in sinus rhythm. Using transthoracic and transesophageal Doppler echocardiography, we recorded transmitral, pulmonary venous, and LAA flow velocity patterns before, 24 hours, and 1 week after cardioversion in all subjects. In the 15 patients who underwent successful cardioversion, the maximal LAA area 24 hours after cardioversion was smaller than the area before cardioversion, whereas LAA ejection fraction during atrial systole and peak atrial systolic emptying velocity of the LAA flow were lower 24 hours after cardioversion than those in the control group. One week after cardioversion, maximal LAA area and LAA peak atrial systolic emptying velocity were restored to levels approximately equivalent to those in the control group, although LAA ejection fraction was lower than in the control group. Maximal LAA area and LAA peak atrial systolic emptying velocity correlated negatively and positively with LAA ejection fraction, respectively, 24 hours and 1 week after cardioversion. These results suggest that LAA and the left atrial main chamber show stunning 24 hours after cardioversion, and the atrial systolic emptying wave of LAA flow is generated by active LAA contraction.

Cross sectional echocardiographic demonstration of the mechanisms of abnormal interventricular septal motion in congenital total absence of the left pericardium

OBJECTIVE

To investigate the influence of the absence of the pericardium on the left ventricular wall, particularly on interventricular septal motion, using M mode and cross sectional short axis echocardiography in patients with congenital total absence of the left pericardium.

METHODS

21 patients with, congenital total absence of the left pericardium were divided into three groups according to the interventricular septal motion; systolic type (n = 6) with paradoxical motion during systole, diastolic type (n = 11) with abnormal posterior motion during mid to late diastole, and mixed type (n = 4) with paradoxical motion during systole and abnormal posterior motion during diastole.

RESULTS

On cross sectional short axis echocardiograms of the left ventricle, in the diastolic type the degree of angular displacement of the papillary muscles during end diastole to end systole showed excessive anticlockwise rotation about the long axis of the left ventricle without marked anteroposterior displacement. In the systolic type, there was shift of the left ventricle towards the anteromedial portion in systole and towards the posterolateral portion in diastole without significant rotation. There was a significantly positive correlation between the degree of angular displacement and the amplitude of diastolic interventricular septal motion during mid to late diastole in all patients.

CONCLUSIONS

There was abnormal interventricular septal motion during systole and diastole in patients with total absence of the left pericardium. Abnormal systolic motion was induced by anteroposterior displacement of the left ventricle, and abnormal diastolic motion by left ventricular rotation about the long axis of the heart during the cardiac cycle. Analysis using cross sectional echocardiography was useful for elucidating the mechanisms of abnormal interventricular septal motion.

The 'sail sound' and tricuspid regurgitation in Ebstein's anomaly: the value of echocardiography in evaluating their mechanisms

We describe a patient with Ebstein's anomaly in whom Doppler echocardiography was used to clarify the mechanism responsible for 'sail sound' and tricuspid regurgitation associated with this condition. Phonocardiography revealed an additional early systolic heart sound, consisting of a first low-amplitude component (T1) and a second high-amplitude component (T2, 'sail sound'). In simultaneous recordings of the tricuspid valve motion using M mode echocardiography and phonocardiography, the closing of the tricuspid valve occurred with T1 which originated at the tip of the tricuspid leaflets, while T2 originated from the body of the tricuspid leaflets. Using color Doppler imaging, the tricuspid regurgitant signal was detected during pansystole, indicating a blue signal during the phase corresponding to T1 and a mosaic signal during the phase corresponding to T2 at end-systole. Thus, 'sail sound' in patients with Ebstein's anomaly is not simply a closing sound of the tricuspid valve, but a complex closing sound which includes a sudden stopping sound after the anterior and/or other tricuspid leaflets balloon out at systole.

The structure and function of phytochrome A: the roles of the entire molecule and of its various parts

Phytochrome A is readily cleavable by proteolytic agents to yield an amino-terminal fragment of 66 kilodalton (kDa), which consists of residues 1 to approximately 600, and a dimer of the carboxy-terminal 55-kDa fragment, from residue 600 or so to the carboxyl terminus. The former domain, carrying the tetrapyrrole chromophore, has been studied extensively because of its photoactivity, while less attention has been paid to the non-chromophoric portion until quite recently. However, the evidence gathered to date suggests that this domain is also of great improtance. We present here a review of the structure and the biochemical and physiological functions of the two domains, of parts of these domains, and of the cooperation between them.