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C P Wu

Publications and source records attributed to C P Wu.

13 recordsLinked to original sources
PubMed1991

Distribution of synapses on fast and slow pyramidal tract neurons in the cat. An electron microscopic study.

Distributions of synapses on various portions of fast and slow pyramidal tract neurons (PTNs) in cat motor cortex were studied with electron microscopy. PTNs were identified by their antidromic invasion following stimulation of the medullary pyramid and were classified into fast and slow PTNs according to conduction velocities of their axons. Two fast and two slow PTNs were intracellularly labeled and, by systematic sampling, electron micrographs from various portions of these neurons were examined to compare the distributions of different types of synapses. It was found that most synapses formed on apical and basal dendrites of fast PTNs were with the dendritic shafts. In slow PTNs, while synapses on apical dendrites were mostly axospinous, about 70% of the sampled synapses on basal dendrites of slow PTNs were established with the dendritic shafts. Virtually all synapses on apical dendrites of slow PTNs belonged to asymmetrical type and most of the synapses sampled from basal dendrites of fast PTNs were also asymmetrical. On the other hand, about 29% of the synapses found on apical dendrites of fast PTNs were symmetrical and a trend was observed for this type of synapses to increase their number with increasing proximity to the cell body. Over 28% of the synapses on basal dendrites of slow PTNs were also symmetrical and seemed to be mainly distributed in layer VI. All synapses formed on the soma were symmetrical both for the fast and slow PTNs.

Animals↗
PubMed1991

Distribution of synapses on an intracellularly labeled small pyramidal neuron in the cat motor cortex.

The morphological characteristics and distribution of synapses on a small pyramidal neuron in layer III of the cat motor cortex have been studied by combining intracellular HRP staining and electron microscopic examination. The stained neuron showed spiny apical and basal dendritic profiles under the light microscope, and exhibited the morphological features of a pyramidal neuron. Ultrastructural analysis indicated that about 80% of the presynaptic terminals formed asymmetrical synapses with spines of distal apical and basal dendrites. On proximal apical dendrites, 64% of the synapses were found to make contact with spines, and 16.7% of the synapses were of symmetrical type and formed with dendritic shafts. Two types of terminal could be identified on the soma; they were alternately located and established symmetrical and asymmetrical synaptic contacts respectively. Possible functional implications are discussed.

Animals↗
PubMed1991

Cellular origin of renal cell carcinoma--an immunohistological study on monoclonal antibodies.

It has been recognized in recent years that renal cell carcinoma possesses a proximal convoluted tubules origin. In an attempt of further intensive evaluation we assayed 51 renal cell carcinomas and 38 additional normal kidney specimens with 4 kidney segment-specific antibodies (Uro-2/S4, Uro-5/T16, Uro-10/T43, Anti Tamm-Horsfall Protein) directed against the nephrotic cells by indirect immunohistological techniques. Consistently stable staining was developed in the tests. The results showed that the majority of renal clear cell carcinomas expressed nephrogenous properties of proximal convoluted tubules but in part also of distal tubules and collecting ducts. Granular cell carcinoma mostly demonstrated histogenic appearance of distal convoluted tubules.

Antibodies, Monoclonal↗
PubMed1991

The prostate in eunuchs.

In 1960, there were 26 eunuchs from the palace of the Qing Dynasty still living in Beijing. The authors took that unique opportunity of carrying out a general physical examination, including palpation of the prostate, for every one of them. Their average age then was 72 years (59-83 years). They became eunuchs at the age of 10-26 years. The prostate was impalpable in 26 (81%) and 1-2 cm in width rectally in five, with a flat surface. At the time of the examination they had been eunuchs on the average for 54 years (41-65 years). This is probably the largest series of human beings followed for such a long period of time to confirm that testicular hormone is essential for the development and preservation of the prostate. The type of operation, the traditional way of carrying out the operation and the usual complications are presented.

Aged↗
PubMed1990

Multi-organ involvement in urothelial malignancies.

The present study covers 1213 patients with urothelial tumours, of whom 113 have been affected by multi-organ malignancies. The disease was found to spread mostly in direction of the urine flow. Bladder was the most frequently affected organ. The incidence of pelvic cancer in China is higher than in Western countries.

Carcinoma, Transitional Cell↗
PubMed1990

Vicissitude of management of ureteral stones.

Following the use of rigid ureteroscopic lithotripsy (URS) in 1984 and extracorporeal shock wave lithotripsy (ESWL) in 1987, the treatment for ureteral stones has undergone significant changes. Our experience showed that the successful rate of URS for 132 patients was 89.4% and for the upper third was rather low, percutaneous antegrade URS should be considered. 376 patients treated with ESWL in prone position with a successful rate of 96.8%. The applicability of open surgery was reduced to 17.8% in 1987 and 14.5% in 1988.

Adolescent↗
PubMed1989

Age factor in post-nephrectomy compensatory renal growth.

In a retrospective investigation we found that the endogenous creatinine clearance (Ccr) of 35 nephrectomized patients was lower than that of normal people of comparable age with two intact kidneys. The Ccr level in the post-nephrectomy patients appeared to correlate with the age of the patients at the time of nephrectomy. The average Ccr value was 99.2 ml/min in the younger group, and 54.9 ml/min in the older group. Furthermore, we also found that the measurement of the remaining kidney in the younger group was larger than that of the matched control group, but no difference was found between the measurement of the remaining kidney in the older group and that of the matched control group. Therefore, we suggest that the remaining kidney in patients over 50 years of age may be described as "a low compensatory kidney". The results from an experimental study of Wistar rats indicated that the dry and wet weights of the remaining kidneys of the younger rats which had undergone neptrectomy were 1.53 X 10(-3) g/gwt, and 5.89 X 10(-3) g/gwt respectively, vs 1.05 X 10 g/gwt and 3.82 X 10(-3) g/gwt in older ones. In tissue culture using serum of younger nephrectomized rats, the amount of 3H-TdR incorporation into the monolayer cells of renal cortex was 1,405.4 CPM, whereas it was 1,025.4 CPM by using serum of older nephrectomized rats. In addition, the cells of renal cortices from both younger and older rats had a similar response to the same serum from nephrectomized rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[The measurement of airway responsive index in normal individuals and asthmatic patients].

Measurement of airway responsiveness to nonallergenic stimuli can be used to confirm the diagnosis of asthma, document the severity of airway responsiveness, and follow changes in airway responsiveness with time in relation to treatment or exposure to occupational sensitizers. Methacholine inhalation is the preferred test for the clinical laboratory as it is more sensitive than exercise or cold air, and there are fewer side effects than with histamine. Airway responsiveness to nonspecific, pharmacologic, bronchoconstricting stimuli has been described using various methods of summarizing dose-response data. The purpone of this study was to examine a simple index of nonspecific airway responsiveness to methacholine, i.e., the slope of a straight line approximation of the dose-response curve. Twelve normal and 19 asthmatic volunteers were studied. Subjects underwent a standard methacholine challenge test, both specific airway conductance (SGaw) and forced expiratory volume of one second (FEV1) were measured. We examined the relationship between response assessed by SGaw or FEV1 and dose of methacholine in each subject. The results showed that, in most of the subjects, the decline of pulmonary function with increasing dose of methacholine almost followed a simple linear relationship. A straight line extending from the origin to the last data point obtained approximating this relationship provides a reasonable summary of each plot. This were true not only in asthmatic subjects but also in normals, and not only for FEV1 but also for SGaw. The slope of this straight line was denominate as responsive index. The summary dose-response slope effectively separated asthmatic from normal subjects without any overlapping; this was true not only when FEV1 but also for SGaw was used as the parameter of response. The responsive index was much greater among asthmatics than among normal subjects (P less than 0.001). The responsive index from the parameter of SGaw was nearly perfectively correlated with which was from FEV1 (r = 0.989, P less than 0.001). We considered that airway responsive index can be calculated not only when FEV1 but also SGaw was used as a parameter of pulmonary function response. The dose-response slope calculated in the present analysis is a summary of the overall dose-response relationship and thus differs from the slope of the latter part of the log dose-response curve. It has the advantage of providing a single, continuous, easily interpreted measure of responsiveness for all subjects.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1986

Thalamic projection to motor area and area 3a of the cat cerebral cortex.

The distributions of thalamic neurons projecting to the motor cortex and cortical area 3a were studied in cat by means of the retrograde double-labeling technique using Nuclear Yellow (NY) and Fast Blue (FB) as tracers. Following injection of NY and FB into the motor cortex and area 3a respectively, the NY-labeled neurons were found to be mainly located in ventrolateral (VL) nucleus and FB-labeled neurons in ventro-posterolateral nucleus (VPL). However, these two kinds of neurons were intermingled with each other in the border area between VL and VPL. A small number of neurons were double-labeled by both NY and FB. They were also distributed in the border area. Some of them could often be found in centromedian and parafascicular nuclei.

Animals↗
PubMed1986

Direct synaptic linkage of ventrolateral nucleus of thalamus terminal with cat fast pyramidal tract neuron.

An electron microscopic study on the synaptic connections between neurons of ventrolateral nucleus of thalamus (VL) and pyramidal tract neurons (PTNs) in cat motor cortex was conducted by means of the anterograde degenerating procedure coupled with horseradish peroxidase (HRP) intracellular staining. Following VL lesions, a large majority of the degenerating terminals were found to terminate on dendritic spines and a few on the dendritic shaft. An asymmetric type synapse formed by a VL degenerating terminal and the dendritic shaft of a branch of apical dendrite of a labeled fast pyramidal tract neuron was demonstrated.

Animals↗
PubMed1985

Connections between pericruciate cortex and the medullary reticulospinal neurons in cat: an electrophysiological study.

The connections between the pericruciate cortex and the medullary reticulospinal (RS) neurons were studied in anesthetized cat. Intracellular recordings were made from reticulospinal neurons and the effects of stimulating different areas of the pericruciate cortex were compared. EPSPs were elicited in all the 93 neurons studied which were antidromically activated by spinal stimulation and had an IS-SD notch on the ascending limb of their antidromic spikes. According to the conduction velocity (c.v.) of the axon and the minimal EPSP latency to cortical stimulation, the neurons could be divided into two groups, i.e. fast-conducting RS neurons (FRS neurons, c.v. greater than 45 m/s) and slow-conducting RS neurons (SRS neurons, c.v. less than 45 m/s). The minimal latencies of FRS neurons were equal to or shorter than 2 ms whereas those of SRS neurons were longer than 2 ms. EPSPs with short latency (less than 2 ms) could be evoked in FRS neurons by stimulating a relatively wide cortical area including the major part of precruciate area 4 and area 6, with a central area of strongest excitatory effect located in area 4 slightly medial to the tip of the cruciate sulcus. Stimulation of the postcruciate area 4 only produced long latency EPSPs. By extrapolation from the cortical and peduncular latencies and the conducting distances it was revealed that the earliest part of the minimal latency EPSPs were monosynaptically evoked in FRS neurons and were mediated by fast-conducting corticobulbar fibers. FRS neurons could be excited by stimuli applied to both ipsilateral and contralateral pericruciate cortex. The influence from the contralateral cortex was slightly stronger.

Animals↗