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Song XJ, Hu SJ, Greenquist KW, Zhang JM, LaMotte RH. Mechanical and thermal hyperalgesia and ectopic neuronal discharge after chronic compression of dorsal root ganglia. J Neurophysiol 1999; 82:3347-58. [PMID: 10601466 DOI: 10.1152/jn.1999.82.6.3347] [Citation(s) in RCA: 232] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronic compression of the dorsal root ganglion (CCD) was produced in adult rats by implanting a stainless steel rod unilaterally into the intervertebral foramen, one rod at L(4) and another at L(5). Two additional groups of rats received either a sham surgery or an acute injury consisting of a transient compression of the ganglion. Withdrawal of the hindpaw was used as evidence of a nocifensive response to mechanical and thermal stimulation of the plantar surface. In addition, extracellular electrophysiological recordings of spontaneous discharges were obtained from dorsal root fibers of formerly compressed ganglia using an in vitro nerve-DRG-dorsal root preparation. The mean threshold force of punctate indentation and the mean threshold temperature of heating required to elicit a 50% incidence of foot withdrawal ipsilateral to the CCD were significantly lower than preoperative values throughout the 35 days of postoperative testing. The number of foot withdrawals ipsilateral to the CCD during a 20-min contact with a temperature-controlled floor was significantly increased over preoperative values throughout postoperative testing when the floor was 4 degrees C (hyperalgesia) and, to a lesser extent, when it was 30 degrees C (spontaneous pain). Stroking the foot with a cotton wisp never elicited a reflex withdrawal before surgery but did so in most rats tested ipsilateral to the CCD during the first 2 postoperative weeks. In contrast, the CCD produced no changes in responses to mechanical or thermal stimuli on the contralateral foot. The sham operation and acute injury produced no change in behavior other than slight, mechanical hyperalgesia for approximately 1 day, ipsilateral to the acute injury. Ectopic spontaneous discharges generated within the chronically compressed ganglion and, occurring in the absence of blood-borne chemicals and without an intact sympathetic nervous system, were recorded from neurons with intact, conducting, myelinated or unmyelinated peripheral nerve fibers. The incidence of spontaneously active myelinated fibers was 8.61% for CCD rats versus 0.96% for previously nonsurgical rats. We hypothesize that a chronic compression of the dorsal root ganglion after certain injuries or diseases of the spine may produce, in neurons with intact axons, abnormal ectopic discharges that originate from the ganglion and potentially contribute to low back pain, sciatica, hyperalgesia, and tactile allodynia.
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Xu H, Hu SJ, Han Y, Long KP. [Protein kinase a mediated excitatory adrenergic effect on chronically compressed dorsal root ganglion neurons in rats]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1999; 51:615-22. [PMID: 11498930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
With a model of chronically compressed dorsal root ganglion (CCD), the present study was undertaken to test how the plasticity of sympathetic-sensory coupling is and whether the coupling is mediated by intracellular messenger PKA by analysing extracellularly recorded spontaneous activity of single A-fibers originating from the CCD neurons in vitro. Eighty-five out of 95 neurons from injured DRGs during application of norepinephrine (NE) were adrenosensitive. Among the 85 neurons, 44 exhibited excitation, 21 showing excitation followed by suppression, 6 displaying alternated excitation and suppression, and 14 suppression. In addition, adrenosensitivity was observed in 15 silent injured DRGs. The excitatory effect of NE was blocked by alpha 1 and alpha 2 adrenoceptor antagonists yohimbine (10 mumol/L) or prazosin (5 mumol/L). Rp-cAMPS (50-250 mumol/L, n = 6), a specific inhibitor of PKA, and H-89 (10 mumol/L, n = 6), an inhibitor of PKA catalytic subunit, obviously suppressed the NE-evoked excitation. Furthermore, the excitatory effect of NE was attenuated by SQ 22, 536 (1 mmol/L), an adenylate cyclase inhibitor (n = 6). The above results demonstrate that injury to DRG neuron body triggered the adrenosensitivity, which was mediated by alpha 1, alpha 2 adrenoceptors and PKA.
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Long KP, Hu SJ, Duan YB, Xu H. [Pattern and dynamic changes of integer multiples in spontaneous discharge of injured dorsal root ganglion neurons]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1999; 51:481-7. [PMID: 11498943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
For the purpose of the present investigation, spontaneous discharges of dorsal root ganglion (DRG) neurons of the rats, which had undergone 3-10 days' chronic compression, were studied. It was found that the interspike interval (ISI) of 17 out of 156 fibers had integer multiples temporal rhythm pattern, in which all the ISI were integer multiples of a basic ISI and a return map of their ISI could be constructed as a crystal grid structure. This temporal pattern could be modified by Na+ channel and K+ channel on their membranes. These data indicated the presence of some irregular discharge trains with their intrinsic regularity.
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Xing JL, Hu SJ. Relationship between calcium-dependent potassium channel and ectopic spontaneous discharges of injured dorsal root ganglion neurons in the rat. Brain Res 1999; 838:218-21. [PMID: 10446337 DOI: 10.1016/s0006-8993(99)01682-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The ectopic spontaneous discharges (ESD) of single myelinated dorsal root fiber originated from the injured dorsal root ganglion (DRG) neurons were recorded in vivo. When [Ca(2+)](o) perfusing the injured DRG had been enhanced or caffeine been used, the ESD was inhibited in dose-dependent manner, while using Ni(2+) or EGTA, the ESD facilitated. The increment of [K(+)](o) and the use of TEA could both facilitate the ESD in dose-dependent manner. Apamin, a special antagonist of calcium-dependent potassium channel (K(Ca)), had markedly increased the number of ESD. These results suggest that the generation of ESD has close relation to the activity of K(Ca) channel.
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Chang S, Mao ST, Kuo TP, Hu SJ, Lin WC, Cheng CL. Fractal geometry in urodynamics of lower urinary tract. CHINESE J PHYSIOL 1999; 42:25-31. [PMID: 10405768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
The physiological signals are usually extremely complicated and difficult to analyze. Recently, investigators have tried the fractal dimension that can characterize roughness and self-similarity of them. It turns out that it is also suitable for obtaining the modalities of lower urinary tract during normal micturition. In this investigation, the external urethral sphincter electromyogram (EUS EMG) and the cystometrogram (CMG) of the Wistar rats under both room temperature and cold water stimulation of the bladder are studied. The modified relative differential box-counting (RDBC) method is used to calculate the fractal dimensions of EMG and CMG time series. According to the experimental results, the modalities of micturition for the Wistar rats can be characterized as normal if both the fractal dimensions of EMG and CMG are of low values during voiding. Furthermore, the technique is validated in identifying the dyssynergia of the bladder and EUS under cold water stimulation.
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31
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Lai KK, Hu SJ, Minato S, Kodaira K, Tan KS. Terrestrial gamma ray dose rates of Brunei Darussalam. Appl Radiat Isot 1999; 50:599-608. [PMID: 10070718 DOI: 10.1016/s0969-8043(98)00080-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
GPS-indexed in-situ and car-borne survey of terrestrial gamma-ray dose rates were carried out in Brunei and adjacent areas using two portable NaI(Tl) counters. The mean and population weighted average dose rates for Brunei are 34 and 33 nGy/h, respectively. The car-borne data and the in-situ data when spectral analysed separately, were found to show fractal behaviour with D of 1.7 and 1.8, respectively. A contour map of the dose rates was also produced.
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Hu SJ, Fernandez R, Jones JW. Cyclosporine A stimulates proliferation of vascular smooth muscle cells and enhances monocyte adhesion to vascular smooth muscle cells. Transplant Proc 1999; 31:663-5. [PMID: 10083285 DOI: 10.1016/s0041-1345(98)01739-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chen LM, Hu SJ, Wei GZ. [Apamin sensitive component of Ca(2+)-activated K+ current of afterhyperpolarization, IAHP, in dorsal root ganglion neurons in rat]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1998; 50:163-8. [PMID: 11324530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Whole-cell voltage clamp technique was used to record the tail current in freshly isolated dorsal root ganglion (DRG) neurons of rat with an aim to investigate whether these neurons possess an apamin sensitive component of Ca(2+)-activated K+ current, IAHP. The results are as follows: (1) the amplitudes of the tail currents increased from 9.3 +/- 2.8 pA to 64.1 +/- 3.4 pA (P < 0.001) when the depolarizing duration was increased from 1 ms to 180 ms; (2) the amplitudes of the tail current were reduced when repolarizing pulses were applied, with a reversal potential of about -63 mV; (3) the amplitude of the tail current was significantly depressed or even almost completely blocked by extracellularly applied 500 mumol/L Cd2+ or intracellularly applied 11 mmol/L EGTA; (4) the amplitudes of the tail currents were decreased by about (26.32 +/- 3.9)% (P < 0.01) after 200 nmmol/L apamin was extracellularly applied; and (5) the fast component of the tail current was sensitive to 10 mmol/L TEA while the slow component was insensitive. These results suggest that an apamin sensitive component of Ca(2+)-activated K+ current may be present in afterhyperpolarization of DRG neurons.
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Hu SJ, Huang YW. [Alteration of inositol phosphate metabolism in aortic smooth muscle cells from spontaneously hypertensive rat]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1997; 49:95-8. [PMID: 9812839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The changes of inositol phosphates in quiescent and GTP gamma S activated vascular smooth muscle cells (VSMC) derived from aorta of spontaneously hypertensive rat (SHR) were examined. The inositol phosphate assay revealed that there was no difference in the inositol-1, 4, 5-triphosphate (InsP3) level between the quiescent VSMCs of SHR and that of normotensive Wistar-Kyoto rats (WKY). G-protein activator GTP gamma S caused a dose- and time-dependent increase in the InsP3 level in VSMCs. Activated G proteins increased significantly the InsP3 level in VSMCs of SHR. In conclusion, the highly sensitive reactivity to GTP gamma S in the generation of InsP3 in VSMCs from SHR may be related to the possible abnomality of the number, substructure or function of some components in G proteins, phosphoinositide turnover.
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Hu SJ, Huang YW, Li Y. [G proteins-phosphoinositide pathways in hypertension]. SHENG LI KE XUE JIN ZHAN [PROGRESS IN PHYSIOLOGY] 1996; 27:31-6. [PMID: 8731980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The second messenger inositol-1,4,5-trisphosphate (InsP3) comes from two major pathways, one is initiated by a family of G protein-linked receptors and the other by receptors linked by tyrosine kinases. These separate receptors activate phospholipase C to hydrolyse phosphatidylinositol-4,5-bisphosphate to give both diacylglycerol and InsP3. The latter then mobilizes stored calcium and promotes an influx of external calcium. The alpha subunit of a newly discovered G protein (Gq) has recently been shown to stimulate the activity of PLC-beta 1. The alpha subunits of the Gq class of G proteins includes G alpha q, G alpha 11, G alpha 14, G alpha 15 and G alpha 16. The important pathologic changes in hypertension are arteriolar spasm and wall thickening. Many vasoactive substances can induce contractile response and proliferation of vascular smooth muscle cells and increase InsP3 level. However, the hypertension does not cause any persistent change in Gq.
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Hu SJ, Katagiri H, Kobayashi H. Effect of modified calm conditions on nuclear dispersion estimates. HEALTH PHYSICS 1995; 68:67-70. [PMID: 7989197 DOI: 10.1097/00004032-199501000-00008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
When the definition of calm in atmospheric diffusion analyses is changed from 0.5 m s-1 to 0.1 m s-1, actual and more accurate low wind speeds and wind directions can be used to calculate the average air concentrations due to continuous releases of radionuclides at 10-m stack height more realistically and accurately. However, this modified calm condition has little affect on the calculated adult thyroid exposure for a postulated accident.
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Hu SJ, Inselmann G, Mohr K, Nellessen U. Lack of inotropic effect of cyclosporin A in isolated guinea pig left atria. Cardiovasc Res 1993; 27:172-5. [PMID: 8472267 DOI: 10.1093/cvr/27.2.172] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVE Cyclosporin A is being widely used to prevent graft rejection in organ transplantation and to treat autoimmune diseases. Since various toxic side effects have been observed, the aim of this study was to look for even a subtle deleterious effect of cyclosporin A on cardiac inotropy in electrically stimulated guinea pig left atria. METHODS The left atrial muscles of guinea pigs, in Tyrode's solution containing 2.7 or 5.4 mM potassium, were electrically stimulated by one of two methods: (1) continuously at 3 Hz, during which cyclosporin A was applied cumulatively (from 10(-9) to 10(-5) M); or (2) stimulated intermittently at 2.5 Hz in 5 mM cyclosporin A, with rest periods of 4 s duration interposed every 4 min. The effects of cyclosporin A on contractile force were observed for 150 min in the first stimulation method, and the effects on the steady state contractile force and amplitude of post-rest contraction were observed for 240 min in the second method. RESULTS The steady state contractile force of the atria declined within the 4 h period at 2.7 mM potassium in Tyrode's solution both in the cyclosporin A group (n = 10) and in the control group (n = 5) to 68(SD 11)% and to 63(4)%, respectively. After 4 h the amplitudes of the post-rest contraction were 101(16)% and 101(4)% in cyclosporin A and control groups, respectively. At 5.4 mM potassium, the following values were obtained (cyclosporin A v control): steady state force 70(8)% (n = 11) v 69(8)% (n = 5); post-rest force 105(9)% v 102(7)%. CONCLUSIONS Cyclosporin A does not influence the steady state contractile force or the amplitude of the post-rest contraction, suggesting the absence of inotropic effects on isolated guinea pig left atria.
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Hu SJ, Weng ZC, Jiang SJ, Gu JW. [Humoral factors in the modulation of sustained discharges of polymodal nociceptors]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1990; 42:428-36. [PMID: 1980550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
By using a model of sustained discharges of polymodal nociceptors (PMN) due to injection of a compound algogenic substance into the skin in anesthetized rats, it was found that stimulation of the sciatic nerve inhibited or facilitated at first and then inhibited the PMN sustained discharges markedly. In a crossperfused preparation, stimulation of the sciatic nerve of donor rat caused the similar effects on sustained discharges of PMN of the recipient rat. Injection of the animal serum after stimulation of the sciatic nerve affected PMN activity obviously. The inhibitory course of most units could not be reversed by naloxone. In the animal tolerance to morphine, the effects of stimulation of the sciatic nerve could still be obtained. Preadministration of reserpine almost completely abolished the facilitatory effect. The results indicate that sustained activity of PMN could be modulated by some humoral factors due to somatic afferents. The inhibitory substances in the humoral factor seem to be both opioid and nonopioid in nature. The facilitatory substance seem to be a catecholamine.
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Chan MK, Hu SJ, Shuen YM, Koo KL, Tsang AY, To MT, Leung WK, Yo WO. Development of an automated human sperm quality system. Phys Med Biol 1990; 35:413-22. [PMID: 2320669 DOI: 10.1088/0031-9155/35/3/009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A computer-automated system, including hardware and software components, is developed for objective assessment of human sperm density and other characteristics, including morphological abnormalities and motility. The hardware component essentially consists of an IBM AT, a relatively low-cost image processing board and other inexpensive commercially available instruments. On the other hand, the software component is developed through the incorporation of image analysis, pattern recognition and modelling techniques with the knowledge of human reproduction from the available literature. The whole system is expected to produce a practical and cost-effective means for the routine assessment of human semen quality.
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Jen CJ, Hu SJ, Wu HJ, Lin TS, Mao CW. Platelet-fibrin interaction in the suspension and under flow conditions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1990; 281:277-85. [PMID: 2102618 DOI: 10.1007/978-1-4615-3806-6_29] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Interactions between platelets and fibrin are important in hemostasis but often confused with platelet-fibrinogen interactions. A stirred mixture of solubilized fibrin and washed platelets at neutral pH range showed drastic reduction in turbidity and concomitant platelet adhesion onto newly formed fibrin strands. This platelet-fibrin interaction did not require platelet activation nor did it cause platelet aggregation. A device consisting of a parallel-plate flow chamber mounted on a fluorescence microscope has been constructed to allow direct visualization and recording of platelet-fibrin interaction under flow conditions. Platelets in whole blood adhered to the fibrin-coated portion but not to the uncoated portion of the flow chamber. Slow motion playback of video tapes indicated that the adhesion phenomenon was a dynamic process that involved attaching, detaching, relocation and transient contact. The fibrin coating influenced platelet adhesion both by increasing the number of cells making short-term attachments to the surface and by increasing the duration of cells attached to the surface. These observations provided basic characteristics of platelet-fibrin interaction.
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Hu SJ, Zhu J. [The facilitatory effect of sympathetic efferents on sustained discharges of polymodal nociceptors]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1989; 41:592-6. [PMID: 2626686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Injection of a compound algogenic substance into receptive field of the skin induced sustained discharges of polymodal nociceptors in rats. The sustained discharges were obviously increased by stimulation of the sympathetic nerve innervating the receptive field. Initial facilitation was followed by the inhibition of discharges in partial units. The sympathetic effect can be activated repeatedly and lasted for a prolonged time. Injection of norepinephrine (5 micrograms/0.2 ml) into the local artery could cause the similar effect. Results indicate that the sympathetic efferents facilitates the sustained discharges of polymodal nociceptors. The possibility of producing causalgia and contrary results of experiments were discussed.
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Hu SJ, Weng ZC. [Influence of stimulation of the skin receptive field on evoked discharges of the polymodal nociceptors in rats]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1988; 40:437-43. [PMID: 3251356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Sun RL, Guo CY, Hu SJ, Yu PZ, Tian RG, Chen X. Clinical application of antitachycardia pacemaker. A report of 6 cases. Chin Med J (Engl) 1988; 101:731-6. [PMID: 3150705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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Jen CJ, Hu SJ. Direct platelet-fibrin interaction that does not require platelet activation. THE AMERICAN JOURNAL OF PHYSIOLOGY 1987; 253:H745-50. [PMID: 3116860 DOI: 10.1152/ajpheart.1987.253.4.h745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Interactions between platelets and fibrin are important in hemostasis but often confused with platelet-fibrinogen interactions. Fibrin solubilized in NaBr-acetic acid formed polymers in neutral pH buffers. A stirred mixture of solubilized fibrin and washed human platelets at neutral pH range showed drastic reduction in turbidity and concomitant platelet adhesion onto newly formed fibrin strands. Optimally, more than 99% of platelets could be associated with fibrin, whereas only 3% of erythrocytes were trapped in the fibrin network under similar conditions. This platelet-fibrin interaction was fibrin concentration dependent and polymerization stage dependent. It preceded any detectable platelet release of serotonin. Gly-Pro-Arg-Pro (250 times in excess) retarded the kinetics of fibrin polymerization as well as that of platelet-fibrin interaction. However, factors affecting platelet activation showed little effect on platelet-fibrin interaction. Our results support the existence of a platelet-fibrin interaction that does not require platelet activation.
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Abstract
One hundred and sixty-nine patients underwent electrophysiologic study for atrioventricular block. Forty-five (27%) had intra-Hisian block. Four of these 45 patients had unusual etiologies: rheumatoid arthritis, cysticercosis cellulosae, Behcet's disease, and Takayasu aorto-arteritis. Their clinical and electrophysiologic features are described in detail.
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Liu YT, Wu WL, Chiang MH, Hu SJ. Factors affecting the production of amphotericin A. ZHONGHUA MINGUO WEI SHENG WU JI MIAN YI XUE ZA ZHI = CHINESE JOURNAL OF MICROBIOLOGY AND IMMUNOLOGY 1987; 20:247-56. [PMID: 3322702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Factors affecting amphotericin A synthesis of Streptomyces nodosus, NDMC-034 were studied. Iron, magnesium and manganese were found to stimulate amphotericin A synthesis at concentrations ranging from 10-100 microM. The optimum inoculum size, and the pH of production medium before sterilization for producing amphotericin A, were found to be near 10% (v/v) and pH 7.8, respectively. Carrying out fermentation in a complex medium using pharmamedia as nitrogen source resulted in an amphotericin A yield of up to 3.4 g/liter. A novel isolation and purification process for amphotericin A from the fermentation broth was developed, using an extracting isopropyl alcohol and methanolic solution containing 2% CaCl2. Amphotericin A exhibits a much lower acute toxicity in mice than amphotericin B.
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Sun RL, Wang FZ, Hu SJ, Tian RG. Intra-Hisian block associated with unusual etiologies. Chin Med J (Engl) 1987; 100:167-72. [PMID: 3113837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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Hu SJ, Chen M, Tian QL, Zhang SJ. [Different effects of sympathetic stimulation on evoked and spontaneous discharges of the polymodal nociceptors in the rat]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1986; 38:232-42. [PMID: 3775405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Hu SJ, Chen X, Sun RL. [Differentiation of ventricular tachycardia from supraventricular tachycardia by the His bundle electrogram in 10 patients]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 1984; 12:268-70, 316. [PMID: 6544210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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Hu SJ, Koo WK, Tan KL. Radioactivity associated with amang upgrading plants. HEALTH PHYSICS 1984; 46:452-455. [PMID: 6693279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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