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861.
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Rahim Mohammadi Moein Mehrtash Moeid Mehrtash Seyedeh-Sepideh Sajjadi 《Journal of investigative surgery》2016,29(3):149-156
Aim of the study: Adipose tissue possesses a population of multi-potent stem cells which can be differentiated to a Schwann cell phenotype and may be of benefit for treatment of peripheral nerve injuries. Effects of local therapy of nonexpanded adipose stromal vascular fraction (SVF) on peripheral nerve regeneration was studied using allografts in a rat sciatic nerve model. Materials and Methods: Thirty male white Wistar rats were divided into three experimental groups (n = 10), randomly: Sham-operated group (SHAM), allograft group (ALLO), SVF-treated group (ALLO/SVF). In SHAM group left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis muscle was sutured. In the ALLO group the left sciatic nerve was exposed through a gluteal muscle incision and transected proximal to the tibio-peroneal bifurcation where a 10 mm segment was excised. The same procedure was performed in the ALLO/SVF group. The harvested nerves of the rats of ALLO group were served as allograft for ALLO/SVF group and vice versa. The SHAM and ALLO groups received 100 μL phosphate buffered saline and the ALLO/SVF group received 100 μL SVF (2.25 ± 0.45 × 107 cells) locally where the grafting was performed. Results: Behavioral, functional, biomechanical, and gastrocnemius muscle mass showed earlier regeneration of axons in ALLO/SVF than in ALLO group (p < .05). Histomorphometic and immunohistochemical studies also showed earlier regeneration of axons in ALLO/SVF than in ALLO group (p < .05). Conclusions: Administration of nonexpanded SVF could accelerate functional recovery after nerve allografting in sciatic nerve. It may have clinical implications for the surgical management of patients after nerve transection. 相似文献
864.
《Injury》2018,49(12):2203-2208
BackgroundThe aim of this study was to compare the fascia-iliaca compartment block and the intra-articular hip injection in terms of pain management and the need for additional systemic analgesia in the preoperative phase of intracapsular hip fractures.MethodsPatients >65 years old with an intracapsular hip fracture were randomized in this prospective, blind, controlled, parallel trial in a Level-I trauma center. Patients were randomly assigned to receive either the fascia-iliaca compartment block (cohort FICB) or the intra-articular hip injection (cohort IAHI) upon admission to the emergency department. The primary outcome was pain relief at 20 min, 12 h, 24 h and 48 h after the regional anesthesia, both at rest and during internal rotation of the fractured limb. The Numeric Rating Scale was used. Residual pain was managed with the same protocol in all patients. Additional analgesic drug administration during the 48 h from admission was recorded.ResultsA total of 120 patients with comparable baseline characteristics were analyzed in this study: the FICB group consisted of 70 subjects, while the IAHI group consisted of 50 subjects.Pain was significantly lower in the IAHI group during movement of the fractured limb at 20 min (p < 0.05), 12 h (p < 0.05), 24 h (p < 0.05) and 48 h (p < 0.05).In the FICB cohort 72.9% of patients needed to take oxycodone, in contrast to 28.6% of the IAHI cohort (p < 0.05). In the FICB cohort 14.09 ± 11.57 mg of oxycodone was administered, while in the IAHI cohort 4.38 ± 7.63 mg (p < 0.05). No adverse events related to either technique were recorded.ConclusionsIntra-articular hip injection provides better pre-operatory pain management in elder patients with intracapsular hip fractures compared to the fascia-iliaca compartment block. It also reduced the need for supplementary systemic analgesia.Level of EvidenceTherapeutic Level I. 相似文献
865.
Makoto Yanagihara Teruhiko Makino Tadamichi Shimizu Takashi Mochizuki 《Journal of cutaneous pathology》2018,45(6):423-427
Lichen aureus is a rare, chronic, persistent purpuric dermatosis clinically characterized by striking yellow‐ to bronze‐colored lesions. Histologically, lichen aureus differs from other pigmented purpuric dermatoses in containing dense, band‐like infiltrates closely associated with the epidermis. This report describes 2 patients with lichen aureus, a 20‐year‐old woman with a lesion on her right arm and a 51‐year‐old man with a lesion on the right side of his groin. Skin biopsy specimens revealed almost identical findings in both patients, including dense band‐like infiltrates containing lymphocytes, histiocytes with hemosiderin deposits scattered extravasated red blood cells and nerve alterations at the dermo‐epidermal interface. The nerves within the lesions were filled with granules, which stained positive with antibody to microtubule‐associated protein 1A/1B‐light chain 3, suggesting autophagy within the nerves. These altered nerves were present only in areas of band‐like dermal lymphocytic infiltration. Electron microscopy of the lesions showed the accumulation of autophagosomes in Schwann cells. 相似文献
866.
《The International journal of neuroscience》2012,122(9):1292-1302
The cerebral vessels are innervated by sympathetic, parasympathetic, and sensory nerves. A sensory innervation of the cerebral vessels originating in the trigeminal ganglion has been described in a number of species by several investigations. It has been shown that the electrical stimulation of the trigeminal ganglion causes an increase of cerebral cortical blood flow (CCoBF). The aim of the present study was to determine the effects of dental electrical stimulation the CCoBF in rabbits. A stimulating electrode was located in the upper right incisor tooth of rabbits and trigeminal ganglion was stimulated orthodromically via the infraorbital nerve. Variations in the cortical CCoBF were evaluated by laser-Doppler flowmetry. In experiment group, CCoBF increased together with the beginning of electrical stimulation (5 V, 0.5-ms impulse duration, square-shaped, 10-Hz frequency). The right and left hemisphere CCoBF values of stimulation period at 15s, 30s, 45s, 60s, 75s, and 90s were significantly higher than those of baseline and 105 and 120s (p < 0.05). The maximum increase in right and left CCoBF was 15.6% and 15.1% respectively. In post-stimulation period, the right CCoBF decreased gradually and returned to the baseline values at 120 s. In experiment groups, the CCoBF values of right hemisphere were comparable that of left hemisphereL (p > 0.05). This study demonstrated that the electrical stimulation of the trigeminal nerve's infraorbital branch via dental pulp increases the cortical right and left CCoBF under physiological conditions. 相似文献
867.
《The International journal of neuroscience》2012,122(11):1537-1559
The isoprenoid pathway and its metabolites--digoxin, dolichol, and ubiquinon--were assessed in autism. The isoprenoid pathway and digoxin status was also studied for comparison in individuals of differing hemispheric dominance to determine the role of cerebral dominance in the genesis of autism. There was an upregulation of the isoprenoid pathway as evidenced by elevated HMG CoA reductase activity in autism. Digoxin, an endogenous Na+-K+ ATPase inhibitor secreted by the hypothalamus, was found to be elevated and RBC membrane Na+-K+ ATPase activity was found to be reduced in autism. Membrane Na+-K+ ATPase inhibition can result in increased intracellular Ca2+ and reduced magnesium levels. Hypothalamic digoxin can modulate conscious and subliminal perception and its dysfunction may lead to autism. Digoxin can also preferentially upregulate tryptophan transport over tyrosine resulting in increased levels of depolarizing tryptophan catabolites--serotonin, quinolinic acid (NMDA agonist), strychnine (blocks glycinergic inhibitory transmission), and nicotine (promotes dopamine release) and decreased levels of hyperpolarizing tyrosine catabolites--dopamine, noradrenaline, and morphine--contributing to membrane Na+-K+ ATPase inhibition. Increased nicotine levels can produce increased dopaminergic transmission in the presence of low dopamine levels. NMDA excitotoxicity could result from hypomagnesemia induced by membrane Na+K+ ATPase inhibition and quinolinic acid, an NMDA agonist acting on the NMDA receptor. Hypomagnesemia and increased dolichol level can affect glycoconjugate metabolism and membranogenesis leading on to disordered synaptic connectivity in the limbic allocortex and defective presentation of viral antigens and neuronal antigens contributing to autoimmunity and viral persistance important in the pathogenesis. Membrane Na+-K+ ATPase inhibition can produce immune activation, a component of autoimmunity. Mitochondrial dysfunction consequent to altered calcium/magnesium ratios and reduced ubiquinone levels can result in increased free radical generation and reduced free radical scavenging and defective apoptosis leading to abnormal synaptogenesis. Autism can thus be considered a syndrome of hypothalamic digoxin hypersecretion consequent to an upregulated isoprenoid pathway. The biochemical patterns including hyperdigoxinemia observed in autism correlated with those obtained in right hemispheric chemical dominance. Right hemispheric chemical dominance is a predisposing factor for autism 相似文献
868.
We report a unique case of a horizontal manifest latent nystagmus (MLN) that is converted to a congenital nystagmus (CN) on covering the subjectþs only seeing eye. The subject is a 65-year-old female who, at five days after birth, had her right eye ennucleated. A prosthetic eye was fitted soon after. Horizontal eye movements were recorded using an IRIS (Skalar Medical) infrared system. The effect of visual feedback on primary and secondary gaze, smooth pursuit, optokinetic responses, and the role of selective attention on fixation stability were examined. On primary gaze with the left eye open and under normal viewing conditions, the patient exhibited a typical MLN waveform. The slow phase was a decreasing velocity and the fast phase beat to the left. On covering the left eye, the nystagmus slow phase immediately increased in velocity and the fast phase beat to the right. Removal of visual feedback (darkness or stabilising the retinal image) also brought about a change from MLN to CN. Both the MLN and CN states were strongly influenced by gaze. The decreasing velocity MLN slow phase was also seen to change to a grossly extended slow phase during periods of visual disengagement. On occasions, these oscillations became a short burst of right-beating CN whenever the patient lost interest in the visual task. This is the first report of an adult subject who can exhibit either of two separate and sustained nystagmus states, an MLN or a CN, whenever the only eye is covered. Two explanations are offered to account for the presence of the two separate waveforms. Central to our interpretation is that the neural integrator has an eccentric null and that it is under a variable gain control. Furthermore, we propose that future models of nystagmus generation will need to include retinal image and attention control loops. 相似文献
869.
870.
IntroductionPara pharyngeal tumors often pose a challenge to surgeons for surgical interventions. Maxillofacial access osteotomies offer excellent visualization and permit unhindered surgical manipulation. Access osteotomy allows the surgeon an adequate access of the surgical field to resect the tumor completely and to preserve vital structures. Though numerous techniques exist, selection of the proper technique is the key factor in reestablishing the function and cosmesis. This article describes our experience with mandibular swing approach that has facilitated complete removal of a parapharyngeal space tumor.Case presentation35years old female complained of deviation of tongue to one side and swallowing difficulty. Clinical and radiographic examinations were suggestive of a skull base lesion involving the hypoglossal nerve. After evaluation the tumor was excised through a mandibulotomy approach. Post operatively the patient was relieved completely of the symptoms and without any postoperative sequalae.Clinical discussionAccessibility is the main concern while dealing with skull base lesions. But the success of surgery lies on the selection of right approach. Paramedian mandibular swing approach has its own advantages over various other facial osteotomies. The swinging of the mandible gives advantage of accessing neck and skull base together, which is not possible with other facial osteotomies.ConclusionManagement of skull base tumors involve a multidisciplinary approach. Choosing the right approach is often a major dilemma. Access osteotomies of facial skeleton is a hatchway to the skull base lesions. Of which mandibular swing approach is a good option for skull base tumors because of the ease of surgical technique even in inexperienced hands. 相似文献