Optimal vacuum erectile device therapy regimen for penile rehabilitation in a bilateral cavernous nerve crush rat model.

BACKGROUND: Vacuum erectile device (VED) therapy has been widely used in penile rehabilitation after radical prostatectomy; however, there is no consensus on the best regimen. OBJECTIVES: To explore an optimal VED therapy regimen in bilateral cavernous nerve crush (BCNC) rat model. MATERIALS AND METHODS: Adult male rats were used to measure the effects of different durations (1-30 min) of VED treatment on penile length, penile blood gas analysis, and adverse effects. Forty-eight adult male rats were randomly divided into Sham, BCNC, and VED treatment groups (2-3-2-3 min, 4-3-3 min, 5-5 min, and 10 min). Penile length, erectile function, and side effects were detected after VED treatment. Histopathological staining and Western blotting were performed to explore the cellular and molecular changes. RESULTS: Prolongation of the duration of VED treatment significantly decreased the penile oxygen saturation, partial oxygen pressure, and arterial blood ratio (P < 0.05). Compared with the BCNC group, all VED treatment regimens partially reversed BCNC-induced penile shortening and erectile dysfunction (P < 0.0001), with the 4-3-3-min and 5-5-min treatment groups exhibiting more significant improvement than the 10-min and 2-3-2-3-min treatment groups (P < 0.0001). The mechanism may be related to the up-regulation of the smooth muscle cell/collagen ratio, endothelial nitric oxide synthase, and α-smooth muscle actin (all P < 0.0001); and the down-regulation of hypoxia-inducible factor-1α, transforming growth factor-ß1, and apoptosis (all P < 0.0001). The incidence of adverse effects in the 2-3-2-3-min treatment group was the highest. DISCUSSION: The commonly used VED therapy regimens maintained erectile function and penile length of BCNC rat by relieving hypoxia and fibrosis, and no further benefits were observed with increased treatment frequency or prolonged treatment duration. CONCLUSION: Two consecutive 5-min treatments with a short interval is the optimal VED therapy regimen for penile rehabilitation in BCNC rat model.

The effect of hemostatic agents and tissue adhesive on injured peripheral nerve healing in rats - Part I. Electrophysiological study.

BACKGROUND: In the practice of maxillofacial surgery, bleeding and nerve injury have common problems. In the control of bleeding, hemostatic agents and tissue adhesives have been frequently used. The effect of these hemostatic agents and tissue adhesives on the injured neural tissues has not been known. OBJECTIVES: In this study, we aimed to investigate the effects of hemostatic agents and tissue adhesive on injured nerve tissues. MATERIAL AND METHODS: Forty-two rats randomly divided into seven groups: Control, Oxidized Regenerated Cellulose (ORC), Gelatine Sponge (GS), Bovine Collagen (BC), Ankaferd BloodStopper (ABS), Glutaraldehyde Surgical Adhesive (BioGlue®) and N-butil-2 cyanoacrylate (Glubran®2). The left sciatic nerves were crushed and surrounded by hemostatic agents and tissue adhesives. At the end of 12 weeks, the surgical site was reopened and electrophysiological recordings were performed. RESULTS: In the ORC, GS, and BC groups, the compound action potential (CAP) values were lower compared to the control group (p < 0.05). Although the values of CAP in the ABS group were higher than in the control group while CAP values in the BioGlue and Glubran®2 groups were lower than the control group, there was no statistical significance between the experimental and control groups (p > 0.05). In the ORC, BC, GS, and Glubran®2 groups, the nerve conduction velocities (NCV) values were lower than in the control group (p < 0.05). In the ABS and BioGlue groups, NCV values were lower compared to the control group but no significant differences were found (p > 0.05). CONCLUSIONS: The present study provides evidence that ABS is the most suitable hemostatic agent due to its favorable effect on the healing of injured neural tissues. BioGlue is also a suitable surgical agent with no adverse effects.

The sensitivity of two-dimensional hindlimb joint kinematics analysis in assessing functional recovery in rats after sciatic nerve crush.

Walking analysis in the rat is increasingly used to assess functional recovery after peripheral nerve injury. Here we assess the sensitivity and specificity of hindlimb joint kinematics measures during the rat gait early after sciatic nerve crush injury (DEN), after twelve weeks of recovery (REINN) and in sham-operated controls (Sham) using discriminant analysis. The analysis addressed gait spatiotemporal variables and hip, knee and ankle angle and angular velocity measures during the entire walking cycle. In DEN animals, changes affected all studied joints plus spatiotemporal parameters of gait. Both the spatiotemporal and ankle kinematics parameters recovered to normality within twelve weeks. At this time point, some hip and knee kinematics values were still abnormal when compared to sham controls. Discriminant models based on hip, knee and ankle kinematics displayed maximal sensitivity to identify DEN animals. However, the discriminant models based on spatiotemporal and ankle kinematics data showed a poor performance when assigning animals to the REINN and Sham groups. Models using hip and knee kinematics during walking showed the best sensitivity to recognize the reinnervated animals. The model construed on the basis of hip joint kinematics was the one combining highest sensitivity with robustness and high specificity. It is concluded that ankle joint kinematics fails in detecting minor functional deficits after long term recovery from sciatic nerve crush and extending the kinematic analysis during walking to the hip and knee joints improves the sensitivity of this functional test.

Thermographic evaluation of hind paw skin temperature and functional recovery of locomotion after sciatic nerve crush in rats.

INTRODUCTION: Peripheral nerves are often damaged by direct mechanical injury, diseases, and tumors. The peripheral nerve injuries that result from these conditions can lead to a partial or complete loss of motor, sensory, and autonomic functions, which in turn are related to changes in skin temperature, in the involved segments of the body. The aim of this study was to evaluate the changes in hind paw skin temperature after sciatic nerve crush in rats in an attempt to determine whether changes in skin temperature correlate with the functional recovery of locomotion. METHODS: Wistar rats were divided into three groups: control (n = 7), sham (n = 25), and crush (n = 25). All groups were subjected to thermographic, functional, and histological assessments. RESULTS: ΔT in the crush group was different from the control and sham groups at the 1st, 3rd and 7rd postoperative days (p<0.05). The functional recovery from the crush group returned to normal values between the 3rd and 4th week post-injury, and morphological analysis of the nerve revealed incomplete regeneration at the 4th week after injury. DISCUSSION: This study is the first demonstration that sciatic nerve crush in rats induces an increase in hind paw skin temperature and that skin temperature changes do not correlate closely with functional recovery.

Thermographic evaluation of hind paw skin temperature and functional recovery of locomotion after sciatic nerve crush in rats

INTRODUCTION: Peripheral nerves are often damaged by direct mechanical injury, diseases, and tumors. The peripheral nerve injuries that result from these conditions can lead to a partial or complete loss of motor, sensory, and autonomic functions, which in turn are related to changes in skin temperature, in the involved segments of the body. The aim of this study was to evaluate the changes in hind paw skin temperature after sciatic nerve crush in rats in an attempt to determine whether changes in skin temperature correlate with the functional recovery of locomotion. METHODS: Wistar rats were divided into three groups: control (n = 7), sham (n = 25), and crush (n = 25). All groups were subjected to thermographic, functional, and histological assessments. RESULTS: ΔT in the crush group was different from the control and sham groups at the 1st, 3rd and 7rd postoperative days (p<0.05). The functional recovery from the crush group returned to normal values between the 3rd and 4th week post-injury, and morphological analysis of the nerve revealed incomplete regeneration at the 4th week after injury. DISCUSSION: This study is the first demonstration that sciatic nerve crush in rats induces an increase in hind paw skin temperature and that skin temperature changes do not correlate closely with functional recovery.

Escalated regeneration in sciatic nerve crush injury by the combined therapy of human amniotic fluid mesenchymal stem cells and fermented soybean extracts, Natto.

Attenuation of inflammatory cell deposits and associated cytokines prevented the apoptosis of transplanted stem cells in a sciatic nerve crush injury model. Suppression of inflammatory cytokines by fermented soybean extracts (Natto) was also beneficial to nerve regeneration. In this study, the effect of Natto on transplanted human amniotic fluid mesenchymal stem cells (AFS) was evaluated. Peripheral nerve injury was induced in SD rats by crushing a sciatic nerve using a vessel clamp. Animals were categorized into four groups: Group I: no treatment; Group II: fed with Natto (16 mg/day for 7 consecutive days); Group III: AFS embedded in fibrin glue; Group IV: Combination of group II and III therapy. Transplanted AFS and Schwann cell apoptosis, inflammatory cell deposits and associated cytokines, motor function, and nerve regeneration were evaluated 7 or 28 days after injury. The deterioration of neurological function was attenuated by AFS, Natto, or the combined therapy. The combined therapy caused the most significantly beneficial effects. Administration of Natto suppressed the inflammatory responses and correlated with decreased AFS and Schwann cell apoptosis. The decreased AFS apoptosis was in line with neurological improvement such as expression of early regeneration marker of neurofilament and late markers of S-100 and decreased vacuole formation. Administration of either AFS, or Natto, or combined therapy augmented the nerve regeneration. In conclusion, administration of Natto may rescue the AFS and Schwann cells from apoptosis by suppressing the macrophage deposits, associated inflammatory cytokines, and fibrin deposits.

Loss of glial fibrillary acidic protein (GFAP) impairs Schwann cell proliferation and delays nerve regeneration after damage.

Axonal loss causes disabling and permanent deficits in many peripheral neuropathies, and may result from inefficient nerve regeneration due to a defective relationship between Schwann cells, axons and the extracellular matrix. These interactions are mediated by surface receptors and transduced by cytoskeletal molecules. We investigated whether peripheral nerve regeneration is perturbed in mice that lack glial fibrillary acidic protein (GFAP), a Schwann-cell-specific cytoskeleton constituent upregulated after damage. Peripheral nerves develop and function normally in GFAP-null mice. However, axonal regeneration after damage was delayed. Mutant Schwann cells maintained the ability to dedifferentiate but showed defective proliferation, a key event for successful nerve regeneration. We also showed that GFAP and the other Schwann-cell-intermediate filament vimentin physically interact in two distinct signaling pathways involved in proliferation and nerve regeneration. GFAP binds integrin alphavbeta8, which initiates mitotic signals soon after damage by interacting with fibrin. Consistently, ERK phosphorylation was reduced in crushed GFAP-null nerves. Vimentin instead binds integrin alpha5beta1, which regulates proliferation and differentiation later in regeneration, and may compensate for the absence of GFAP in mutant mice. GFAP might contribute to form macro-complexes to initiate mitogenic and differentiating signaling for efficient nerve regeneration.

PAF antagonism modifies neuroprotective action of histone deacetylase and calcineurin phosphatase inhibitors in mice.

To evaluate the hypothesis that platelet activating factor (PAF) antagonism may affect the functional recovery following the nerve injuries and also to evaluate the effect of PAF receptor antagonism on the neuroprotective effect of tacrolimus and sodium valproate, effect of PAF receptor antagonist, WEB2086 was evaluated in animal models of sciatic nerve crush and endothelin-1 induced focal cerebral ischemia. WEB2086, per se, while attenuating spontaneous sensory motor recovery after sciatic nerve crush, enhanced functional recovery after focal cerebral ischemia. WEB2086 also attenuated the neuroprotective effect of tacrolimus and sodium valproate subsequent to peripheral nerve injury, while it significantly improved the neuroprotective action of tacrolimus and sodium valproate following cerebral ischemia reperfusion injury. These results suggest that PAF receptor antagonists alone and in combination with tacrolimus/sodium valproate could be used in the treatment of cerebral ischemia reperfusion injuries however, their use following peripheral nerve injuries could be detrimental.

Prolonged focal application of polyethylene glycol induces conduction block in guinea pig spinal cord white matter.

A 2-min focal application of Polyethylene Glycol (PEG) to injured mammalian spinal cords can offer significant yet limited restoration of functional and structural integrity. However, longer application of PEG has not been tested in similar injuries. In this study, isolated spinal cord white matter strips from adult guinea pigs were subjected to a 25 min exposure of PEG (MW: 2000; 50% w/w), with or without prior compression. When applied in a continuous steam, PEG, with a delay of about 6 min, suppressed the compound action potential (CAP) amplitude to 64+/-4% of the pre-PEG level in uninjured cords and to 64+/-7% in compressed cord strips. Both recovered to 70+/-5% (uninjured) and 88+/-11% (compressed) of the pre-PEG level following wash. When PEG was applied in a pulsatile manner, no significant decrease of CAP amplitude was observed. In summary, our results show that focal continuous application of PEG has minimal toxicity if applied for less than 5 min. Pulsatile application could extend this duration to at least 25 min with no toxicity. This study could be useful in determining the optimal protocol for the use of PEG in both animal research and human spinal cord victims.

Lesión del nervio radial por explosión de bolsa de aire: informe de un caso y revisón de la literatura / Radial nerve injury produced by explosion of car air bag: Case report and review of literature

Se informa el caso de una paciente quien sufrió múltiples traumatismos como consecuencia de la explosión de una bolsa neumática protectora en un impacto automovilístico a baja velocidad. Entre las lesiones ocurridas sufrió parálisis del nervio radial como consecuencia de la contusión a nivel del tercio medio del brazo, se describe su evolución y se hace una revisión de la literatura internacional.

Estenosis degenerativa del canal lumbar tratamiento quirurgico mediante recalibrado / Degenerative stenosis of lumbar space and surgical tratment by recalibration

Se presenta el caso de un paciente masculino de 62 anos, diagnosticado de estenosis degenerativa del canal lumbar, tratado quirurgicamente mediante la tecnica del recalibrado con buen resultado del tratamiento.

Reinnervating rat skeletal muscle: effect of 35% grade treadmill exercise.

To determine the effect of 35% grade treadmill running on reinnervating rat skeletal muscle, adult rats were exercised for 1 hour on a 35% grade motorized treadmill, at a speed of 27m/min, once and twice daily, 5 days a week from the 3rd to the 6th week after sciatic nerve crush. Compared to the crush denervated control, the crush-denervated-twice exercised group decreased in the content of sarcoplasmic proteins (15.2%, p less than 0.05), and in the contraction time of the soleus (8.9% p less than 0.05). The percentage of type II fiber types in the plantaris increased 15% (p less than 0.05) in the once and 10% (p less than 0.05) in the twice daily exercised group. The findings of this study suggest that treadmill training performed during reinnervation did not cause muscle damage and may have increased the "fast" type muscle properties in the rat skeletal muscle.