Mechanical sensitivity of group III and IV afferents from posterior articular nerve in normal and inflamed cat knee

1986 ◽  
Vol 55 (4) ◽  
pp. 635-643 ◽  
Author(s):  
P. Grigg ◽  
H. G. Schaible ◽  
R. F. Schmidt
Keyword(s):  
Sciatic Nerve ◽  
Knee Joint ◽  
Conduction Velocity ◽  
Mechanical Stimulation ◽  
Dorsal Root ◽  
Receptive Fields ◽  
Group Iv ◽  
Mechanical Sensitivity ◽  
Group Iii ◽  
Stimulation Of

Recordings were performed from sciatic nerve or dorsal root filaments in 28 cats to study single group III (conduction velocity 2.5-20 m/s) and group IV (conduction velocity less than 2.5 m/s) units supplying the knee joint via the posterior articular nerve (PAN). In seven of these cats the knee joint had been inflamed artificially. Recordings from sciatic nerve filaments revealed responses to local mechanical stimulation of the joint in only 3 of 41 group IV units and in 12 of 18 group III units from the normal joint. In the inflamed joint 14 of 36 group IV units and 24 of 36 group III units were excited with local mechanical stimulation. In recordings from dorsal root filaments (normal joint) 4 of 11 group IV units and 7 of 13 group III units were activated by stimulating the joint locally. In the normal joint four group IV units (recorded from dorsal root filaments) responded only to rotations against the resistance of the tissue, whereas the majority of the fibers did not respond even to forceful movements. Group III units with local mechanosensitivity in the normal joint reacted strongly or weakly to movements in the working range of the joint or only to movements against resistance of the tissue. In the inflamed joint, group IV fibers (recorded in sciatic nerve filaments) with detectable receptive fields responded strongly to gentle movements or only to movements against resistance of tissue. Some did not react to movements. Group III units reacted strongly or weakly to gentle movements or only to movements against resistance of the tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Responses of neurons in VPL and VPL-VL region of the cat to algesic stimulation of muscle and tendon

1983 ◽  
Vol 49 (3) ◽  
pp. 649-661 ◽  
Author(s):  
K. D. Kniffki ◽  
K. Mizumura
Keyword(s):  
Electrical Stimulation ◽  
Mechanical Stimulation ◽  
Receptive Fields ◽  
Transitional Zone ◽  
The Other ◽  
Group Iii ◽  
Group I ◽  
Nociceptive Information ◽  
Noxious Mechanical Stimulation ◽  
Stimulation Of

1. The responses evoked by electrical stimulation of cutaneous and muscle nerves, by noxious and innocuous mechanical stimulation of muscle, tendon, and cutaneous tissues, and by intra-arterial (ia) injection of algesic substances (potassium, bradykinin) into arteries supplying the gastrocnemius-soleus muscle (GS) were studied in single neurons located in the ventroposterolateral nucleus (VPL) and in the transitional zone between VPL and the ventrolateral nucleus (VL) of cats lightly anesthetized with thiopenthal. Such chemical stimulation of the muscles has been shown to activate muscular groups III and IV axons specifically (43, 44) and presumably is nociceptive in character (14, 17, 31). 2. One hundred eight neurons were tested. Eighty-three of the units responded only to various types of cutaneous stimulation of the hindlimb. The other 25 responded to algesic stimulation of muscle and/or tendon. Of these latter 25, 7 had no apparent cutaneous receptive field although 4 of them responded to electrical stimulation of the common peroneal and/or sural nerve. Thus, only three neurons responded exclusively to algesic chemical and noxious mechanical stimulation of the muscle. Of the other 18 neurons, 14 had cutaneous receptive fields restricted to the hindlimb and often responded to non-noxious repetitive light stroking and to noxious pinching with a high-frequency discharge. Four cells (two of which had cutaneous input only from low-threshold mechanoreceptors) had complex and large receptive fields extending to more than one limb. 3. Potassium was a more potent muscle receptor stimulant than bradykinin, the latter only weakly exciting 3 neurons of 24 tested with both substances. The responses to potassium were rapid (approximately 4.0 s in latency) and tended to be greater (have higher response rates) for the units that responded to cutaneous as well as muscle/tendon stimulation. 4. Most neurons that responded to noxious deep stimulation had a threshold for the GS nerve volley in the group III fiber range. The few neurons with thresholds slightly below the group III range did not respond to activation of group I or II muscle spindle afferents by intra-arterial application of succinylcholine or by stretching the muscle. 5. Neurons with responses to any of the muscle, tendon, or cutaneous nociceptive stimuli were located at the ventral and dorsal periphery of VPL and in the VPL-VL transitional zone. 6. These results strongly suggest that there exist regions within the lateral diencephalon of cats that are capable of processing nociceptive information and that these regions are located at the periphery of VPL.

scholarly journals Responses of group III and IV muscle afferents to dynamic exercise

1997 ◽  
Vol 82 (6) ◽  
pp. 1811-1817 ◽  
Author(s):  
Christine M. Adreani ◽  
Janeen M. Hill ◽  
Marc P. Kaufman
Keyword(s):  
Receptive Fields ◽  
Muscle Afferents ◽  
Group Iv ◽  
Dynamic Exercise ◽  
Triceps Surae ◽  
Group Iii ◽  
Low Levels ◽  
Triceps Surae Muscles ◽  
Decerebrate Cats ◽  
Stimulation Of

Adreani, Christine M., Janeen M. Hill, and Marc P. Kaufman.Responses of group III and IV muscle afferents to dynamic exercise. J. Appl. Physiol. 82(6): 1811–1817, 1997.—Tetanic contraction of hindlimb skeletal muscle, induced by electrical stimulation of either ventral roots or peripheral nerves, is well known to activate group III and IV afferents. Nevertheless, the effect of dynamic exercise on the discharge of these thin fiber afferents is unknown. To shed some light on this question, we recorded in decerebrate cats the discharge of 24 group III and 10 group IV afferents while the mesencephalic locomotor region (MLR) was stimulated electrically. Each of the 34 afferents had their receptive fields in the triceps surae muscles. Stimulation of the MLR for 1 min caused the triceps surae muscles to contract rhythmically, an effect induced by an α-motoneuron discharge pattern and recruitment order almost identical to that occurring during dynamic exercise. Eighteen of the 24 group III and 8 of the 10 group IV muscle afferents were stimulated by MLR stimulation. The oxygen consumption of the dynamically exercising triceps surae muscles was increased by 2.5-fold over their resting levels. We conclude that low levels of dynamic exercise stimulate group III and IV muscle afferents.

Processing of Nociceptive Mechanical and Thermal Information in Central Amygdala Neurons With Knee-Joint Input

2002 ◽  
Vol 87 (1) ◽  
pp. 103-112 ◽  
Author(s):  
Volker Neugebauer ◽  
Weidong Li
Keyword(s):  
Knee Joint ◽  
Mechanical Stimulation ◽  
Receptive Fields ◽  
Central Nucleus ◽  
Response Functions ◽  
Central Amygdala ◽  
Deep Tissue ◽  
Stimulus Response ◽  
Noxious Mechanical Stimulation ◽  
Stimulation Of

Pain has a strong emotional dimension, and the amygdala plays a key role in emotionality. The processing of nociceptive mechanical and thermal information was studied in individual neurons of the central nucleus of the amygdala, the target of the spino-parabrachio-amygdaloid pain pathway and a major output nucleus of the amygdala. This study is the first to characterize nociceptive amygdala neurons with input from deep tissue, particularly the knee joint. In 46 anesthetized rats, extracellular single-unit recordings were made from 119 central amygdala neurons that were activated orthodromically by electrical stimulation in the lateral pontine parabrachial area and were tested for receptive fields in the knee joints. Responses to brief mechanical stimulation of joints, muscles, and skin and to cutaneous thermal stimuli were recorded. Receptive-field sizes and thresholds were mapped and stimulus-response functions constructed. Neurons in the central nucleus of the amygdala with excitatory input from the knee joint ( n = 62) typically had large symmetrical receptive fields in both hindlimbs or in all four extremities and responded exclusively or preferentially to noxious mechanical stimulation of deep tissue ( n = 58). Noxious mechanical stimulation of the skin excited 30 of these neurons; noxious heat activated 21 neurons. Stimulus-response data were best fitted by a sigmoid nonlinear regression model rather than by a monotonically increasing linear function. Another 15 neurons were inhibited by noxious mechanical stimulation of the knee joint and other deep tissue. Fifteen neurons had no receptive field in the knee but responded to noxious stimulation of other body areas; 27 nonresponsive neurons were not activated by natural somesthetic stimulation. Our data suggest that excitation is the predominant effect of brief painful stimulation of somatic tissue on the population of central amygdala neurons with knee joint input. Their large symmetrical receptive fields and sigmoid rather than monotonically increasing linear stimulus-response functions suggest a role of nociceptive central amygdala neurons in other than sensory-discriminative aspects of pain.

Effects of an experimental arthritis on the sensory properties of fine articular afferent units

1985 ◽  
Vol 54 (5) ◽  
pp. 1109-1122 ◽  
Author(s):  
H. G. Schaible ◽  
R. F. Schmidt
Keyword(s):  
Knee Joint ◽  
Receptive Fields ◽  
Control Sample ◽  
Group Iv ◽  
Experimental Arthritis ◽  
Present Sample ◽  
Group Iii ◽  
Low Threshold ◽  
Resting Activity ◽  
Passive Movements

An acute experimental arthritis was induced in the right knee joint of adult cats anesthetized with chloralose, and the activity of single fine afferent units of the medial articular nerve was recorded from filaments of the saphenous nerve. All units included in this study were sensitive to local mechanical probing of the medial and anteromedial aspects of the knee joint. The units were identified by their conduction velocity as belonging either to group III (2.5-20 m/s, 48 U) or group IV (less than 2.5 m/s, 29 U). After the identification, the resting activity was measured, and the evoked activity was determined using local mechanical stimulation with glass rods and von Frey hairs, and passive movements of the knee joint. The results were compared with those obtained in a similar study of fine articular units from normal joints. Resting activity was observed in 75% of the group III and 83% of the group IV units. The discharges were irregular and often of high frequency. Both the percentages of units with resting activity and the frequencies of their discharges were more than twice as high as in the control sample. Nearly all units from inflamed joints had low threshold to movements (group III 89%, group IV 72%), and most units responded well to flexion and extension. In contrast, in units from normal joints only 33% of the group III and 10% of the group IV units responded well to passive movements in the normal working range of the joint. In inflamed as well as in normal joints the responses were mostly tonic in character and adapted slowly or not at all when the joint was held in a new position. In normal joints 24% of the group III and 36.5% of the group IV afferent units with local mechanosensitive receptive fields could not be excited by any physiological or noxious joint movements. Such units were only very occasionally seen in the present sample. The average number of receptive fields per unit found in inflamed joints exceeded considerably that in normal units, but no systematic drop in von Frey thresholds was seen when comparing the control sample with the inflamed one. From the above data we conclude that an acute inflammation sensitizes many fine articular units, making them active at rest and increasing the responsiveness more readily to normally innocuous joint movements. Both nociceptors and units with low threshold to movement seem to become sensitized by the inflammation.(ABSTRACT TRUNCATED AT 400 WORDS)

Evidence for a central component in the sensitization of spinal neurons with joint input during development of acute arthritis in cat's knee

1990 ◽  
Vol 64 (1) ◽  
pp. 299-311 ◽  
Author(s):  
V. Neugebauer ◽  
H. G. Schaible
Keyword(s):  
Spinal Cord ◽  
Knee Joint ◽  
Mechanical Stimulation ◽  
Receptive Fields ◽  
Lumbar Spinal Cord ◽  
Mechanical Stimuli ◽  
Spinal Neurons ◽  
Deep Tissue ◽  
Lumbar Spinal ◽  
Stimulation Of

1. In the spinalized cat, nociceptive spinal neurons with knee input show enhanced responses to mechanical stimulation of that joint once an inflammation has developed in the knee. Enhanced responses may result from increased afferent inflow as well as from modifications of the nociceptive processing within the spinal cord. To examine the significance of these components, we tested in 30 chloralose-anesthetized, spinalized cats whether, during development of arthritis, changes of responsiveness in spinal neurons are restricted to stimulation of the inflamed joint or whether responsiveness in these neurons is altered in general. While continuously recording from a neuron, we injected kaolin and carrageenan into one knee and tested the responses to mechanical stimuli applied to the joint and to regions adjacent to and remote from the knee during the developing arthritis. In addition, in six cats we monitored the neurons' responses to electrical stimulation of the sural nerves and the rostral lumbar spinal cord. 2. Of 32 neurons in laminae VI, VII, and VIII of the lumbar spinal cord, 15 ascending and eight nonascending cells were driven by mechanical stimulation of one or both knee joint(s). Nine of these were nociceptive specific (NS), responding exclusively or predominantly to noxious compression of the knee and other deep tissue, and 12 were wide-dynamic-range (WDR) cells with graded responses to gentle and noxious stimuli applied to the knee joint(s), deep tissue, and skin. Two neurons with high ongoing discharges had some excitatory joint input but showed marked inhibition by most stimuli used (INH neurons). The majority of the neurons had receptive fields on both legs. Nine of the 32 neurons had no input from the knee(s). 3. All 23 neurons with joint input became sensitive or more responsive to movements and gentle compression of the inflamed knee once the inflammation had developed. In general, these neurons also showed enhanced responses to compression of the adjacent muscles in thigh and lower leg. In 20 neurons, response properties were even altered for stimuli applied to regions remote from the inflamed joint, including the contralateral leg in 18 cases. We found expansion of initially restricted receptive fields (mainly in NS cells), enhancement of preexisting responses, and/or lowering of threshold to mechanical stimuli applied to these regions; few neurons developed inhibitory reactions.(ABSTRACT TRUNCATED AT 400 WORDS)

Neurons in ventrobasal region of cat thalamus selectively responsive to noxious mechanical stimulation

1983 ◽  
Vol 49 (3) ◽  
pp. 662-673 ◽  
Author(s):  
C. N. Honda ◽  
S. Mense ◽  
E. R. Perl
Keyword(s):  
Sciatic Nerve ◽  
Mechanical Stimulation ◽  
Receptive Fields ◽  
High Threshold ◽  
Noxious Stimulation ◽  
Nociceptive Neurons ◽  
Subcutaneous Tissues ◽  
Alpha Beta ◽  
Lateral Nucleus ◽  
Stimulation Of

1. A survey was made of neurons located in the ventral posterior lateral nucleus of the cat thalamus and its immediate vicinity for elements with specifically nociceptive properties. 2. Pipette microelectrodes filled with a dye solution were used to obtain extracellular recordings of unitary activity in 34 animals anesthetized with chloralose. 3. The great majority of the over 1,000 different single units responding to sciatic nerve stimulation noted in this series of experiments could also be excited by innocuous mechanical stimulation of skin or subcutaneous tissues. An infrequent but consistently noted group of units excited by A-alpha beta delta sciatic nerve volleys did not respond to innocuous mechanical manipulation or A-alpha beta sciatic nerve volleys; they were excited only by either noxious levels of mechanical stimulation or when volleys included the activity of more slowly conducting myelinated fibers. The latencies of such "high-threshold" units to sciatic volleys were longer than those of the other units. 4. Histologically identified recording sites marked by dye were recovered for 17 high-threshold units. Twelve of the 17 could be excited by noxious manipulations of restricted parts of the contralateral hindlimb. Nine of the 12 had cutaneous receptive fields, whereas 3 responded only to stimulation of subcutaneous tissues. None of the 17 high-threshold units evidenced additional discharges that could be correlated with the C-fiber component of sciatic nerve volleys. 5. The high-threshold units typically exhibited a low level of irregular background activity, which increased on repeated noxious stimulation of the peripheral receptive fields. Tactile units of the same or adjacent penetrations usually had a much greater degree of ongoing activity, often marked by bursts at a relatively high frequency. 6. The recording sites for the 17 high-threshold neurons were located dorsal and ventrolateral to the core of the ventrobasal nuclei and were not found in the midst of the low-threshold, cutaneous, mechanoreceptive population. During vertical stereotaxic penetrations, high-threshold units were noted dorsal or ventral to the location of ventrobasal tactile units in a pattern consistent with the core's somatotopic arrangement. 7. These results support the concept that the cat ventrolateral thalamus receives a small but distinct selectively nociceptive projection. The nociceptive neurons appear to be located in a shell that surrounds the main tactile projection to the ventral posterior lateral nucleus and that retains at least part of the topographic arrangement characteristic of the tactile core. Presumably, this projection is part of an organization identifying and localizing noxious stimulation.

Identification of muscle afferents subserving sensation of deep pain in humans

1994 ◽  
Vol 72 (2) ◽  
pp. 883-889 ◽  
Author(s):  
D. A. Simone ◽  
P. Marchettini ◽  
G. Caputi ◽  
J. L. Ochoa
Keyword(s):  
Conduction Velocity ◽  
Receptive Fields ◽  
Extensor Tendon ◽  
Common Peroneal Nerve ◽  
Muscle Afferents ◽  
Group Iv ◽  
High Threshold ◽  
Group Iii ◽  
Muscle Afferent ◽  
Afferent Unit

1. Intraneural microstimulation (INMS) and microneurography were used in combination to stimulate and record from muscle nociceptor primary afferent fibers of the common peroneal nerve of healthy volunteers. When pain evoked by INMS was projected to muscle, afferent activity could be evoked by innocuous and noxious pressure applied within the projected painful area. Conduction velocity of single fibers was determined by stimulating the receptive fields (RFs) electrically via needle electrodes inserted into the RF and measuring conduction latency and distance between the RF and recording electrode. 2. Pain projected to muscle during INMS trains 5–10 s in duration at threshold intensity for pain sensation was typically described as cramping and was well localized. Subjects mapped the area of the painful projected field (PF) over the skin using a pointer. 3. Fourteen slowly adaping mechanoreceptors with RF in muscle and with moderate to high receptor threshold were identified within or near the painful PF. Conduction velocities were in the range of Group III (n = 8) and Group IV (n = 6) fibers. Mean RF areas of Group III and Group IV afferents, determined by applying pressure percutaneously, were 2.71 +/- 1.14 (SE) cm2 and 3.40 +/- 1.08 (SE) cm2, respectively. Only one Group III afferent unit exhibited spontaneous activity (< 1 Hz). 4. One additional high-threshold mechanoreceptor was identified, with its RF located in the extensor tendon at the base of the big toe. This fiber had a conduction velocity of 32 m/s. During INMS, a well-localized sharp pain was projected to the tendon.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Peripheral δ-opioid receptors attenuate the exercise pressor reflex

2013 ◽  
Vol 305 (8) ◽  
pp. H1246-H1255 ◽  
Author(s):  
Anna K. Leal ◽  
Katsuya Yamauchi ◽  
Joyce Kim ◽  
Victor Ruiz-Velasco ◽  
Marc P. Kaufman
Keyword(s):  
Dorsal Root Ganglia ◽  
Opioid Receptors ◽  
Dorsal Root ◽  
Group Iv ◽  
Opioid Agonist ◽  
Group Iii ◽  
Femoral Arteries ◽  
Exercise Pressor Reflex ◽  
Pressor Reflex ◽  
Stimulation Of

In rats with ligated femoral arteries, the exercise pressor reflex is exaggerated, an effect that is attenuated by stimulation of peripheral μ-opioid receptors on group IV metabosensitive afferents. In contrast, δ-opioid receptors are expressed mostly on group III mechanosensitive afferents, a finding that prompted us to determine whether stimulation of these opioid receptors could also attenuate the exaggerated exercise pressor reflex in “ligated” rats. We found femoral arterial injection of [D-Pen2,D-Pen5]enkephalin (DPDPE; 1.0 μg), a δ-opioid agonist, significantly attenuated the pressor and cardioaccelerator components of the exercise pressor reflex evoked by hindlimb muscle contraction in both rats with ligated and patent femoral arteries. DPDPE significantly decreased the pressor responses to muscle mechanoreflex activation, evoked by tendon stretch, in ligated rats only. DPDPE (1.0 μg) had no effect in either group on the pressor and cardioaccelerator responses to capsaicin (0.2 μg), which primarily stimulates group IV afferents. DPDPE (1.0 μg) had no effect on the pressor and cardioaccelerator responses to lactic acid (24 mM), which stimulates group III and IV afferents, in rats with patent femoral arteries but significantly decreased the pressor response in ligated rats. Western blots revealed the amount of protein comprising the δ-opioid receptor was greater in dorsal root ganglia innervating hindlimbs with ligated femoral arteries than in dorsal root ganglia innervating hindlimbs with patent femoral arteries. Our findings support the hypothesis that stimulation of δ-opioid receptors on group III afferents attenuated the exercise pressor reflex.

Response of primate joint afferent neurons to mechanical stimulation of knee joint

1977 ◽  
Vol 40 (1) ◽  
pp. 1-8 ◽  
Author(s):  
P. Grigg ◽  
B. J. Greenspan
Keyword(s):  
Knee Joint ◽  
Dorsal Root ◽  
Joint Angle ◽  
Afferent Neurons ◽  
Time Constants ◽  
Joint Afferents ◽  
Stretch Receptors ◽  
Angular Displacements ◽  
Gastrocnemius Muscles ◽  
Stimulation Of

1. One hundred thirty-eight knee joint afferents from posterior articular nerve (PAN), in primates, were recorded in dorsal root filaments. Responses of afferents were studied in relation to both passive manipulations of the knee and active contractions of quadriceps, semimembranosus, and gastrocnemius muscles. 2. When the knee was passively rotated, most neurons discharged only when extreme angular displacements were achieved. Response of neurons responding to passive extensions was linearly related to the torque applied to the knee. With maintained extensions, discharge in extension neurons adapted slowly. Some of the time constants of adaptation were similar to those for simultaneously recorded torque relaxation. 3. Contractions of quadriceps, semimembranosus, or gastrocnemius muscles could activate many neurons in the absence of changes in joint angle. For quadriceps-activated neurons, rather high torques (mean = 2,450 g with cm) were required. 4. The results support the hypothesis that joint afferents function as capsullar stretch receptors, responding to those mechanical events which result in loading of the capsule.

Primate nucleus gracilis neurons: responses to innocuous and noxious stimuli

1988 ◽  
Vol 59 (3) ◽  
pp. 886-907 ◽  
Author(s):  
D. G. Ferrington ◽  
J. W. Downie ◽  
W. D. Willis
Keyword(s):  
Conduction Velocity ◽  
Dynamic Range ◽  
Subcutaneous Tissue ◽  
Receptive Fields ◽  
High Threshold ◽  
Spinothalamic Tract ◽  
Sinusoidal Vibration ◽  
Nucleus Gracilis ◽  
Pressure Sensitive ◽  
Stimulation Of

1. Recordings were made from 67 neurons in the nucleus gracilis (NG) of anesthetized macaque monkeys. All of the cells were activated antidromically from the ventral posterior lateral (VPL) nucleus of the contralateral thalamus. Stimuli used to activate the cells orthodromically were graded innocuous and noxious mechanical stimuli, including sinusoidal vibration and thermal pulses. 2. The latencies of antidromic action potentials following stimulation in the VPL nucleus were significantly shorter for cells in the caudal compared with the rostral NG. The mean minimum afferent conduction velocity of the afferent conduction velocity of the afferent fibers exciting the NG cells was 52 m/s, as judged from the latencies of the cells to orthodromic volleys evoked by electrical stimulation of peripheral nerves. The overall conduction velocity of the pathway from peripheral nerve to thalamus was approximately 40 m/s. 3. Cutaneous receptive fields on the distal hindlimb usually occupied an area equivalent to much less than a single digit. However, a few cells had receptive fields up to or exceeding the area of the foot. 4. NG cells were classified by their responses to graded mechanical stimulation of the skin as low threshold (LT) or wide dynamic range (WDR). No high-threshold NG cells were found. A special subcategory of pressure-sensitive LT (SA) neurons was recognized. Many of these cells were maximally responsive to maintained indentation of the skin. The sample of NG cells differed from the population of primate spinothalamic and spinocervicothalamic pathways so far examined, in having a larger proportion of LT neurons and a smaller proportion of WDR cells. A few NG cells responded best to manipulation of subcutaneous tissue. 5. Discriminant analysis permitted the NG cells to be assigned to classes determined by a k-means cluster analysis of the responses of a reference set of 318 primate spinothalamic tract (STT) cells. There were four classes of cells based on normalized responses of individual neurons and another four classes based upon responses compared across the population of cells. The NG cells were allocated to the various categories in different proportions than either primate STT cells or spinocervicothalamic neurons, consistent with the view that the functional roles of these somatosensory pathways differ. 6. Some of the pressure-sensitive NG cells were excited when the skin was stretched, suggesting an input from type II slowly adapting (Ruffini) mechanoreceptors.(ABSTRACT TRUNCATED AT 400 WORDS)

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