[Role of p38MAPK signaling pathway in rats with phantom limb pain].

OBJECTIVE: To investigate the role of p38MAPK signal pathway in spinal cord and dorsal root ganglion (DRG) in rats with phantom limb pain and the effects of specific inhibitors.
 Methods: Healthy adult male SD rats (n=48) were cut off one side of the sciatic under anesthesia to establish a model of phantom limb pain. In addition, the healthy rats were taken as a sham group (group S, n=24). The animals were scored by observing the action of chewing (0=no chewing, 13=the worst chewing) after the operation and were sacrificed on the following day after the operation. The successful model of phantom limb pain were randomly divided into 2 groups: a phantom limb pain group (group P, n=24) and a phantom limb pain plus inhibitor group (group P+I, n=24). SB203580 was given to the rat at 0.8 mg/kg on every Monday until the rats were sacrificed, the rest of the rats received an equal amount of saline. Eight rats from each group were randomly taken for the determination of levels of P-p38MAPK in spinal cord and DRG before administration and on the 4th, 6th, 8th weekend following the administration, respectively.
 Results: In the sham group, no animal developed chewing. Meanwhile, rats in successful model of phantom limb pain group began chewing from the 2nd day after operation with scores at eight to eleven. The chewing scores in the P+I group were reduced after the treatment. Compared with group S, P-p38MAPK levels were elevated in groups of P and P+I (P<0.05 or P<0.01). Compared with group P, P-p38MAPK level was decreased in the group P+I (P<0.05 or P<0.01).
 Conclusion: P38MAPK signal pathway involves in the development of phantom limb pain.

Penile Replantation: A Retrospective Analysis of Outcomes and Complications.

Purpose Penile replantation is an uncommonly performed procedure, which can alleviate physical and psychosocial sequelae of penile amputation. This study critically appraises the current literature on penile replantation. Methods A comprehensive literature search of the Medline, PubMed, and Google Scholar databases was conducted with multiple search terms related to penile replantation. Data on outcomes, complications, and patient satisfaction were collected. Results A total of 74 articles met inclusion criteria. One hundred and six patients underwent penile replantation, but outcome, complication, and satisfaction data were not standardized across all patients. Penile amputation most often resulted from self-mutilation or trauma. The majority were complete amputations (74.8%). Full sensation was maintained in 68.4% of patients. Most reported adequate urinary function (97.4%) and normal erection (77.5%). Skin necrosis (54.8%) and venous congestion (20.2%) were the most common complications. Urethral stricture (11.0%) and fistula (6.6%) were common urethral complications. Most (91.6%) patients reported overall satisfaction although there was a lack of patient-reported outcomes. Multivariate analysis suggested that complete amputation (ß = 3.15, 95% CI 0.41-5.89, p = 0.024), anastomosis of the superficial dorsal artery (ß = 9.88, 95% CI 0.74-19.02, p = 0.034), and increasing number of nerves coapted (ß = 1.75, 95% CI 0.11-3.38, p = 0.036) were associated with favorable sexual, urinary, and sensation outcomes. Increasing number of vessels anastomosed (ß = -3.74, 95% CI -7.15 to -0.32, p = 0.032) was associated with unfavorable outcomes. Conclusion Although penile replantation is associated with complications, it has a high rate of satisfaction and efficacy. Coaptation of multiple nerves and anastomosis of the superficial dorsal artery should be completed.

Potential relationship of self-injurious behavior to right temporo-parietal lesions.

Self-injurious behavior (SIB) is associated with several neurologic and psychiatric syndromes but rarely with focal lesions. Two patients with lesions of the right temporo-parietal junction presented to psychiatric inpatient services with SIB in the absence of notable neurologic deficits or suicidal ideation. Right temporo-parietal lesions may be associated with disturbances of agency and body ownership, both of which may facilitate SIB. Misoplegia, or hatred of a limb, may be associated with SIB and has been reported without hemiplegia with a right temporo-parietal lesion. Further study is warranted to improve our understanding of the mechanisms underlying SIB.

Self-mutilation in patients after nerve injury may not be due to deafferentation pain: a case report.

OBJECTIVE: Animals with transected nerves may develop self-mutilating behavior (autotomy) directed at the denervated body part. Autotomy is often thought to be a response to deafferentation pain produced by pathological changes in the dorsal horn, and self-mutilation after dorsal rhizotomy has consequently been used as an outcome measure for the investigation of chronic pain in animal models. A less recognized hypothesis suggests that autotomy is simply an animal's efforts to remove the useless part. We report a case of self-mutilation of the thumb and fingers in a patient with loss of all sensory modalities in the arm after brachial plexus avulsion. CONCLUSION: Asking the patient about the reasons for his self-mutilation provides insights into the cause of autotomy which cannot be established from animal studies. We suggest that autotomy may not be a result of chronic pain, and discuss the human experience and alternative underlying pathological processes.

A novel 6.14 Mb duplication of chromosome 8p21 in a patient with autism and self mutilation.

Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders with a strong genetic etiology. Cytogenetic abnormalities have been detected in 5-10% of the patients with autism. In this study, we present the clinical, cytogenetic and array-comparative genomic hybridization (array-CGH) evaluation of a 13-year-old male with severe developmental delay, facial dysmorphic features, autism and self mutilation. The patient was found to carry a de novo duplication of chromosome region 8p21 of minimally 6.14 and maximally 6.58 Mb as ascertained by bacterial artificial chromosome (BAC)-based array-CGH. Hitherto, only a few patients with autism with cytogenetically visible duplications involving the chromosome 8p21 region have been described, but the extent of these duplications has not been determined at the molecular level. This represents the smallest rearrangement of chromosomal region 8p21 as yet found in a patient with autism. For 11 of the 36 genes with known functions located within this duplication clear transcription in the brain was found. Of those the STMN4 and DPYSL2 genes are the most likely candidate genes to be involved in neuronal development, and, if altered in gene-dosage, in the autistic phenotype of our patient.

Identification of a novel nonsense mutation of the neurotrophic tyrosine kinase receptor type 1 gene in two siblings with congenital insensitivity to pain with anhidrosis.

Objective To explore the aetiology of congenital insensitivity to pain with anhidrosis (CIPA) in two Chinese siblings with typical CIPA symptoms including insensitivity to pain, inability to sweat, and self-mutilating behaviours. Methods Clinical examination and genetic testing were conducted of all available family members, and the findings were used to create a pedigree. Mutation screening using PCR amplification and DNA Sanger sequencing of the entire neurotrophic tyrosine kinase receptor type 1 gene ( NTRK1) including intron-exon boundaries was used to identify mutations associated with CIPA. Results A novel nonsense mutation (c.7C > T, p. Arg3Ter) and a known splice-site mutation (c.851-33 T > A) were detected in NTRK1 and shown to be associated with CIPA. Conclusion Our findings expand the known mutation spectrum of NTRK1 and provide insights into the aetiology of CIPA.

Multisite integumentary squamous cell carcinoma in an African grey parrot (Psittacus erithacus erithacus).

A 22-year-old male African grey parrot (Psittacus erithacus erithacus) had had episodes of chronic feather picking and self-mutilation for 10 years; it had a 5 cm diameter right axillary wound and a 2 cm left dorsal patagial wound. Initial treatment with azithromycin and wound management was unsuccessful. Biopsies of both masses indicated squamous cell carcinoma. The left patagial tumour was removed completely by electrocautery. Cisplatin was administered weekly into multiple sites on the right axillary tumour and it initially appeared to regress; however, the bird's condition deteriorated after a month of treatment, and it was euthanased. The tumour was confirmed postmortem to be squamous cell carcinoma, which had invaded local tissues. The aetiology of the carcinoma may have been secondary to chronic focal trauma.

Regeneration patterns influence hindlimb automutilation after sciatic nerve repair using stem cells in rats.

INTRODUCTION: Hindlimb autophagy is common after rat sciatic total axotomy and is considered as a sign of neuropathic pain. We applied adult stem cells in a fibrin conduit in a total sciatic axotomy model to improve nerve regeneration, investigating whether a correlation could be detected between stem cells effects on regeneration and limb autophagy. MATERIAL AND METHODS: After sciatic nerve section, a 1-cm sciatic gap was crossed using fibrin conduits. Experimental groups included empty fibrin conduits, fibrin conduits seeded with primary Schwann cells, and fibrin conduits seeded with Schwann cell-like differentiated mesenchymal or adipose-derived stem cells (dMSCs and dASCs). Controls were represented by autografts and by sham rats (tot n=34). At 16 weeks post-implantation, regeneration pattern was analysed on histological sections and related to eventual autophagy. Hindlimbs were evaluated and scored according to autophagy Wall's scale and X-Rays radiological evaluation. RESULTS: All regenerative cell lines significantly improved myelination at the mid conduit level, compared to the empty tubes. However, dMSC could not significantly improve myelination at the distal stump, showing a more chaotic regeneration compared to both other cells groups and controls. Autophagy was correlated to this regeneration patterns, with higher autophagy scores in the empty and dMSC group. CONCLUSION: Hindlimb autophagy can be used as index of neuropathic pain due to nerve lesion or on-going immature regeneration. dMSC group was characterized by a less targeted regeneration comparing to dASC and primary Schwann cells, which confirmed their effectiveness in regeneration and potential in future clinical applications.

Pain in Borderline Personality Disorder.

Pain processing in patients with borderline personality disorder (BPD) is abnormal primarily with respect to pain thresholds which are typically elevated or perception of phasic nociceptive stimuli which is reduced. In spite of this common finding, nonsuicidal self-injury (NSSI), often expressed as cutting, is a hallmark sign of the disease and serves to release aversive inner tension. The question thus arises, how does a painful stimulus release inner tension when these patients feel less pain than healthy people? However, intensity discrimination is normal in these patients. Imaging data have provided evidence that inhibitory top-down modulation is increased in BPD patients, and that processing of the affective-emotional pain component is altered. Recent studies have focused on the role of pain, tissue injury and seeing blood in the context of NSSI. Preliminary findings suggest a significant role of pain irrespective of concomitant tissue injury, and of seeing blood expressed as a stronger immediate stress release. Taken together, BPD patients exhibit altered pain processing that can be assigned to altered processing of nociceptive stimuli in prefrontal and limbic brain areas, which may help to mechanistically explain the clinical behavior.

Interpersonal violence, alcohol use, and acquired capability for suicide.

Acquired capability for suicide (ACS), defined as pain tolerance and fearlessness about death, is theorized as necessary to enact suicide. This study examined the associations of interpersonal violence and alcohol use with ACS in 502 college students. General fearlessness/pain tolerance was positively associated with male gender and alcohol use. Fearlessness about death was positively associated with male gender and general physical violence perpetration. However, these risk factors did not explain variance in ACS beyond male gender and history of suicide attempts/nonsuicidal self-injury. These findings add to the understanding of ACS correlates.

Self-mutilation in personality disorders: psychological and biological correlates.

OBJECTIVE: The goal of this study was to determine whether self-mutilators with personality disorders differ from nonmutilators with personality disorders in impulsivity, aggression, and other psychopathology and whether serotonergic dysfunction contributes to self-mutilation. METHOD: Twenty-six self-mutilators with personality disorders were matched to 26 control subjects with personality disorders for gender, age, education, axis I diagnosis of affective disorder, and axis II diagnosis of personality disorder. Numerous indexes of psychopathology as well as CSF 5-hydroxyindoleacetic acid (5-HIAA) levels and platelet imipramine binding sites (Bmax) and affinity (Kd) were determined. RESULTS: Self-mutilators had significantly more severe character pathology, had greater lifetime aggression, and were more antisocial than the control subjects. The self-mutilators scored higher on the Hamilton Rating Scale for Depression but not on the Beck Depression Inventory or the Beck Hopelessness Scale. The two groups did not differ on the Buss-Durkee Hostility and Guilt Inventory or on the Sensation Seeking Scale. The degree of self-mutilation was significantly correlated with impulsivity, chronic anger, and somatic anxiety. Both self-mutilation and impulsivity showed significant negative correlations with Bmax, although the two groups did not differ in CSF 5-HIAA levels or in platelet imipramine binding. CONCLUSIONS: The results demonstrate the contribution of severe character pathology, aggression, impulsivity, anxiety, and anger to self-mutilation and provide preliminary support for the hypothesis of underlying serotonergic dysfunction facilitating self-mutilation.

Self-injurious behavior: a review of the behavior and biology of self-mutilation.

OBJECTIVE: The authors describe the clinical characteristics of self-injurious behavior, giving special emphasis to self-injurious behavior occurring among individuals with character disorders. DATA COLLECTION: They review data suggesting the involvement of serotonergic, dopaminergic, and opiate neurotransmitter systems in the expression of self-injurious behavior. FINDINGS: Self-injurious behavior occurs among mentally retarded individuals, psychotic patients, prison populations, and individuals with severe character disorders. Although theoretical psychological models of self-injurious behavior are helpful in understanding the patient's experience of self-injury, no generally useful therapeutic approach has yet evolved from these models. Data derived from animal models and treatment studies suggest the involvement of opiatergic and dopaminergic mechanisms in self-injury among the mentally retarded. Serotonergic influences on self-injurious behavior may be present in varying forms of this behavior. The scientific literature on the benefits of pharmacological agents for mentally retarded individuals is beset with a number of problems. Support is emerging, however, for the use of lithium and carbamazepine with self-injuring mentally retarded patients, and some behavioral interventions appear to be successful for mentally retarded individuals. Self-injuring patients with borderline personality disorder may benefit from milieu treatment. CONCLUSIONS: Although no form of treatment has yet been demonstrated to be of general benefit, the literature suggests that therapeutic trials with dopamine antagonists, serotonin reuptake inhibitors, and opiate antagonists may be of value.

Autosomal dominant inherited neuropathies with prominent sensory loss and mutilations: a review.

Hereditary sensory neuropathies (HSNs) are rare disorders characterized by progressive distal sensory loss, predominantly affecting the lower limbs. Foot ulcers, severe skin and bone infections, arthropathy, and amputations are frequent and feared complications. Occasionally, patients complain of spontaneous shooting or lancinating pain. Autonomic fibers can be affected to a variable degree. Patients with HSN can also have severe distal weakness, and some HSN variants have therefore been classified among the hereditary motor and sensory neuropathies (HMSNs). Molecular genetic studies of autosomal dominant inherited neuropathies with prominent sensory loss and ulceromutilating features have assigned the genetic loci for HMSN type 2B (Charcot-Marie-Tooth syndrome type 2B) and HSN type 1 to chromosomes 3q13-22 and 9q22.1-22.3, respectively. However, some families with HSN have been excluded for linkage to these loci, suggesting further genetic heterogeneity. Recently, disease-causing mutations in the SPTLC1 gene have been identified in patients with HSN type 1. In this review, we discuss the hallmark features associated with the distinct genetic subtypes of autosomal dominant inherited HSN and provide genotype-phenotype correlations.

The deafferentation syndrome in genetically blind rats: a model of the painful phantom limb.

The hypothesis was tested which states that the somatic deafferentation syndrome is a visually prompted response to sensorimotor loss. The dorsal roots, C5-T2, were bilaterally cut in a strain of rats known to be genetically blind. These complete dorsal rhizotomies left the forelimbs totally anesthetic, analgesic and paretic. Contact and visual placing reactions were absent, and responses to pinprick or pinch were absent. Self-mutilation limited to the distal digits appeared on the first or second postoperative days and then progressed proximally. The forelimbs were symmetrically affected, and no other body parts were mutilated. The spatial precision of this syndrome, in the absence of visual as well as peripheral somatosensory information from the affected limb, indicates that controlled guidance of the behavior arises from an existing central representation of the limb and its relationship with the total body; a phantom limb. Consideration of other reports regarding the deafferentation syndrome leads to the view that it is motivated by disturbing abnormal sensations (pain) of central neural origin.

Intractable postherpetic itch and cutaneous deafferentation after facial shingles.

Some patients develop chronic itch from neurological injuries, and shingles may be a common cause. Neuropathic itch can lead to self-injury from scratching desensate skin. A 39-year-old woman experienced severe postherpetic itch, but no postherpetic neuralgia, after ophthalmic zoster. Within 1 year, she had painlessly scratched through her frontal skull into her brain. Sensory testing and skin biopsies were performed on itchy and normal scalp to generate preliminary hypotheses about mechanisms of neuropathic itch. Quantitation of epidermal neurites in PGP9.5-immunolabeled skin biopsies demonstrated loss of 96% of epidermal innervation in the itchy area. Quantitative sensory testing indicated severe damage to most sensory modalities except itch. These data indicate that in this patient, severe postherpetic itch was associated with loss of peripheral sensory neurons. Possible mechanisms include electrical hyperactivity of hypo-afferented central itch-specific neurons, selective preservation of peripheral itch-fibers from neighboring unaffected dermatomes, and/or imbalance between excitation and inhibition of second-order sensory neurons.

The role of the neuroma in autotomy following sciatic nerve section in rats.

A delay in the formation of the terminal neuroma following sciatic nerve section in rats was obtained by means of free nerve grafts sutured to the proximal stump of the sectioned sciatic nerve branches. The automutilating behaviour in these animals was statistically compared with that which follows single sciatic section and sciatic section plus end-to-end suture. The results showed that in animals with grafted nerve stumps, autotomy begins significantly later than in those with single sciatic section. However, when the self-mutilation started, it followed the same increasing evolution in both groups. These results suggest that autotomy after a nerve section is behaviour related to the aparition and nature of the terminal neuroma.

Autotomy following peripheral nerve lesions: experimental anaesthesia dolorosa.

(1) When hindlimb peripheral nerves are cut across in rats and mice, there is a tendency for the animal to attack the anaesthetic limb. We have called this attack "autotomy". In this paper we describe the time course and degree of autotomy following various types of nerve injury. (2) Four different types of lesion were applied to the sciatic nerve of rats. The most serious autotomy was produced by section of the nerve and encapsulation of its cut end in a polythene tube. Section followed by immediate resuturing also produced serious autotomy. Simple ligation of the nerve end was followed by less autotomy than encapsulation or cut and resuture. A crush lesion caused only minimal attack. (3) Section of the saphenous branch of the femoral nerve produced no autotomy. However, if the saphenous and sciatic nerves were ligated at the same time so that the entire foot became anaesthetic there was a great increase of autotomy over that seen when the sciatic nerve alone was ligated. This increase with the double lesion occurred even if the saphenous nerve was ligated more than 100 days after the sciatic nerve had been cut. (4) Mice showed autotomy very similar to that seen in rats but the onset was somewhat faster. (5) Reasons are given to propose that autotomy is triggered by an abnormal afferent barrage generated in the cut end of the nerve. Autotomy from peripheral nerve lesions is a different phenomenon from that seen after dorsal root section. Autotomy occurs under conditions which produce anaesthesia dolorosa in man. This simple model may be suitable for studies of the prevention of irritations originating from chronic lesions of peripheral nerves.

Autotomy following limb denervation: effects of sparing selected afferents.

Lesions of the brachial plexus are often followed by inflammation, self-inflicted scratching and autotomy of the denervated extremity. If innervation of the shoulder girdle muscles was spared, this denervation syndrome was decreased in incidence and intensity as compared to a full brachial plexus section. Spared innervation increased the latency between the appearance of inflammation and autotomy, revealing a strong linkage between the site of inflammation and the site of autotomy attack. Plexus lesions, which spared one of the nerves of the distal limb, also decreased the incidence and intensity of autotomy and shifted self-attack from autotomy to scratching wounds. Subsequent section of this nerve produced a two-stage brachial plexus denervation, and the cumulated autotomy was markedly less than that produced by a single-stage brachial plexus denervation. Scratching wounds and autotomy exhibited similar latencies. Scratching was directed towards areas of partial innervation and autotomy towards areas of total denervation. The results are discussed in terms of the possible contributions of dysesthesia inflammation and ischemia in scratching behavior and autotomy.

Differential behavioral outcomes in the sciatic cryoneurolysis model of neuropathic pain in rats.

We have previously introduced a novel animal model of neuropathic pain in rats following a peripheral mononeuropathy produced by freezing the common sciatic nerve, a technique termed sciatic cryoneurolysis (SCN). In this study, we have further characterized the temporal pattern of behavioral changes following SCN, including thermal hyperalgesia and mechanical allodynia. These behaviors were assessed using noxious thermal (radiant heat) and non-noxious tactile (von Frey filament) stimuli, respectively. Following unilateral SCN, animals exhibited significant (P < 0.001) bilateral tactile hypersensitivity (allodynia) that persisted at least 10 weeks. However, this lesion did not result in thermal hypersensitivity (hyperalgesia). In fact, thermal sensitivity in the operated limb remained significantly suppressed throughout the 10 weeks (P < 0.001). Furthermore, we observed autotomy in 76% of SCN-lesioned animals as well as transient weight loss and pale eye syndrome (PES), a phenomenon previously unreported in other neuropathic pain models. PES is a sustained, visibly distinct pallor of the normally pink eye color of the albino rat. We believe PES is a putative marker of heightened sympathetic efferent activity. The severity of autotomy following SCN correlated significantly with both weight loss (P < 0.001) and the expression of PES (P < 0.001). Autotomy behavior preceded the onset of allodynia; however, there was no correlation between the severity of expression of these behaviors. These behavioral sequelae are comparable to those seen in other animal models of neuropathic pain, but differ in respect to the increased frequency of autotomy and the lack of thermal hyperalgesia.(ABSTRACT TRUNCATED AT 250 WORDS)

The resolution of neuropathic hyperalgesia following motor and sensory functional recovery in sciatic axonotmetic mononeuropathies.

Nerve lesions producing extensive axonal loss can induce painful hyperalgesic states in man. The affect of axonal regeneration and end-organ reinnervation on hyperalgesia and pain is controversial. This study used two axonotmetic models, the sciatic crush injury (CI) and the sciatic chronic constrictive injury (CCI), to investigate the affects of nerve regeneration and reinnervation on hyperalgesia and presumed painful behavior in rats. The sciatic CI resulted in a transient loss of both sciatic motor function and the withdrawal response to pinch and heat in the sciatic distribution. Extensive recovery of motor function, pinch and heat response occurred over days 23-38 post-crush injury. This temporally corresponded with a plateau in the hindpaw autotomy score and a resolution of the saphenous-mediated pressure and heat hyperalgesia (adjacent neuropathic hyperalgesia; ANH) which developed over the medial dorsum of the hindpaw following the sciatic CI. In contrast, with sciatic transection and distal stump excision, no motor recovery occurs, large areas of the hindpaw remain unresponsive to heat and pinch, and the saphenous mediated ANH fails to resolve over a period of 3 months. When sciatic CI was compared to contralateral sciatic transection within the same rat, the bilateral saphenous-mediated pressure and heat thresholds were initially identical, but by 23-27 days post-crush, the crush side thresholds became hypoalgesic relative to the section side. This demonstrates an attenuation of the crush-induced ANH which temporally corresponds to the recovery of motor and sensory function. When the sciatic nerve was proximally crushed and distally transected (3 cm below the crush site), the saphenous-mediated pressure and heat threshold changes were identical (over 6 weeks of serial testing) to those produced by a contralateral sciatic transection within the same rat. This indicates that the microenvironments surrounding the regenerating axon tips did not differentially affect the development of ANH following sciatic CI or transection. The sciatic CCI resulted in a transient loss of hindpaw motor function without the loss of pinch or heat withdrawal responses in the sciatic distribution. Motor function recovery occurred primarily over days 23-59 post-ligature. During this prolonged period of motor function recovery there was a resolution of the sciatic-mediated plantar surface heat hyperalgesia and the saphenous-mediated heat ANH. The above data support the hypothesis that the successful regeneration of distal axons after axonotmetic lesions can initiate the resolution of neuropathic hyperalgesia.