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Inadequate coronary vasodilator reserve, (1) luminal narrowing of coronary capillaries, (2) and systolic compression of the in tramyocardial small arteries (3) are considered to contribute towards myocardial ischaemia in patients [...]

Background: We hypothesized that altered myocardial perfusion distribution patterns could be seen with coronary distal emboli of different particle sizes using myocardial contrast echocardiography. Methods: In 16 open-chest anesthetized dogs, microsphere suspensions of 9 or 500 @mm in diameter were injected into the left anterior descending coronary artery until the mean left anterior descending coronary artery flow rate was reduced to less than 30% of baseline flow. During baseline conditions and after maximal embolization, real-time myocardial contrast echocardiography was performed by intravenous infusion of an echocontrast agent. Results: In animals infused with 9-@mm microspheres, a transmural perfusion defect was seen at the time of maximal embolization. In contrast, in animals infused with 500-@mm microspheres, a subendocardial perfusion defect was observed. Conclusions: The particle size of coronary distal emboli affects myocardial perfusion distribution.

Background: Although coronary flow reserve (CFR) has been reported to be restricted in various conditions, there has been no report of CFR for patients with congestive heart failure (CHF). The purpose of this study was to assess coronary flow characteristics for patients with CHF. Methods: We studied 15 patients with CHF: 8 with dilated myocardiopathy and 7 with hypertensive heart disease. Phasic coronary flow velocities were obtained in the left anterior descending coronary artery at rest and during hyperemia (0.15 mg/kg/min adenosine triphosphate infusion intravenously) by transthoracic echocardiography before and after treatment of CHF. CFR was obtained from the ratio of hyperemic/baseline diastolic mean velocity. Results: CFR was significantly restricted in the condition of CHF compared with that after improvement of CHF (1.5 +/- 0.2 vs 2.0 +/- 0.3, P < .01). Baseline diastolic mean velocity in the condition with CHF was significantly greater than that after improvement of CHF (41 +/- 13 cm/s vs 33 +/- 13 cm/s, P = .04), although maximal hyperemic diastolic mean velocity was not significantly different before and after improvement of CHF (63 +/- 20 cm/s vs 61 +/- 19 cm/s, P = .68). After improvement of CHF, heart rate, along with left ventricular end-diastolic volume and dimension, were significantly decreased, and deceleration time of transmitral early filling flow was increased compared with before treatment of CHF. Blood pressure and ejection fraction were not significantly different before and after treatment of CHF. Conclusions: Restriction of CFR is demonstrated during CHF because of the elevation of baseline resting flow velocity, which might be related to increase in left ventricular preload and heart rate.

Single neurons were recorded in the inferotemporal cortex (IT) of a monkey trained to discriminate three selected human faces from a large number of different faces. Neurons which were not responsive to non-face visual stimuli used in the task but were responsive to certain sets of faces were found in the gyrus of the IT. The correlation analysis between the quantified facial features and the responses has revealed that face neurons detect the combination of the distances between facial parts such as eyes, mouth, eyebrows, hair, and so on. One of the face neurons detected the combination of the degree that the forehead above the left eye covered with hair and the distance between the eyes and the mouth. The results of this analysis have given appropriate reason for naming the neurons as the face neurons.

Fructose-1,6-bisphosphatase deficiency is an inheritable disorder of gluconeogenesis. Sequence analysis of the cDNA of the fructose-1,6-bisphosphatase mRNA isolated from monocytes from a girl with this disease and her consanguineous parents revealed that the patient and her parents were a homozygote and heterozygotes for an insertion of one G residue at G957GGGG961, respectively. This mutation resulted in translation of a truncated enzyme protein, and the mutant protein showed no fructose-1,6-bisphosphatase activity in an overexpression experiment in Escherichia coli. However, this mutation is located in a region of the amino acid sequence which is not well conserved among mammals. A mutagenized clone was prepared from the normal clone. The extents of substitutions and deletions of the amino acid sequence were predicited to be less in the mutagenized protein than in the mutant protein. This mutagenized clone also expressed no fructose-1,6-bisphosphatase activity, although both of two normal clones from control monocytes and a control liver sample expressed an apparently normal level of fructose-1,6-bisphosphatase activity. Thus, this mutation is concluded to be responsible for fructose-1,6-bisphosphatase deficiency in this patient.

In order to achieve a wide refrigerating temperature range in magnetic refrigeration, it is effective to layer multiple materials with different Curie temperatures. It is crucial to have a detailed understanding of physical properties of materials to optimize the material selection and the layered structure. In the present study, we discuss methods for estimating a change in physical properties, particularly the Curie temperature when some of the Gd atoms are substituted for non-magnetic elements for material design, based on Gd as a ferromagnetic material which is a typical magnetocaloric material. For this purpose, whilst making calculations using the S=7/2 Ising model and the Monte Carlo method, we made a specific heat measurement and a magnetization measurement of Gd-R alloy (R = Y, Zr) to compare experimental values and calculated ones. The results showed that the magnetic entropy change, specific heat, and Curie temperature can be estimated with good accuracy using the Monte Carlo method.

The cobalt ketene complex (III) mentioned in the title is prepared from dicobaltoctacarbonyl (I) and methylene bromide (II) in the presence of Zn.