Anti-hyperalgesic properties of ethanolic crude extract from the peels of Citrus reticulata (Rutaceae).

The therapeutic effects from Citrus reticulata on painful inflammatory ailments are associated to its flavonoids constituent and phytochemical studies with Citrus genus affirm that the peels have important amounts of it. These bioactive compounds have been a considerable therapeutic source and evaluate potential application of the peel extract is significant. This research aims to investigate the influence of ethanolic crude extract from the peels of Citrus reticulata and its possible mechanism of action in different animal models of pain. The extract reduced hyperalgesia in the second phase of formalin test (vehicle: 501.5 ± 40.0 s; C. reticulata extract 300 mg/kg: 161.8 ± 41.1 s), in the carrageenan model (vehicle at 4th h: 82.5 ± 9.6 %; C. reticulata extract 300 mg/kg at 4th h: 47.5 ± 6.5 %) and in Complete Freund's Adjuvant model (vehicle: 501.5 ± 40.0 s; C. reticulata extract 300 mg/kg: 161.8 ± 41.1 s). The possible contribution of opioidergic and adenosinergic systems in the anti-hyperalgesic effect of C. reticulata extract was observed after treatment, with non-selective antagonists for both systems, which produced reversal effects. In conclusion, these properties of C. reticulata extract suggest a potential therapeutic benefit in treating painful conditions.

Early fragmentation of polyester urethane sheet neither causes persistent oxidative stress nor alters the outcome of normal tissue healing in rat skin.

Silicone breast implant is associated with complications inherent to the surgical procedure. Prosthesis coating with polyurethane, however, commonly reduces the incidence of such complications. In this paper, the authors evaluated the inflammatory histomorphometric profile and oxidative damage associated to the implant of polyester urethane sheets. Forty-eight Wistar rats were divided into Sham or polyester urethane groups (n = 8/group) and underwent a polyester urethane implant in the dorsal skinfold. Tissue samples were collected on days seven, 30, and 90 after surgery and subjected to histomorphometric analysis and biochemical tests. Results were analyzed by one-way ANOVA (p ≤ 0.05). Peri-implant tissue samples exhibited characteristic inflammatory response associated with the biomaterial, with increased vascularization on day seven and augmented levels of IL1-b and TNF-a after 30 days. Peri-implant fibrocystic population was small on day seven, but increased considerably after 90 days. A rise in the carbonyl group levels of skin samples in the polyester urethane group was observed on day seven. Findings suggest that polyester urethane sheets undergo biodegradation at an early stage after implantation, followed by increased vascularity and microencapsulation of biomaterial fragments, without persistent oxidative damage. Fiber arrangement inside the collagen matrix results in a fibrotic scar because of polyester urethane degradation.

Ultra-short heart rate variability recording reliability: The effect of controlled paced breathing.

BACKGROUND: Recent studies have reported that Heart Rate Variability (HRV) indices remain reliable even during recordings shorter than 5 min, suggesting the ultra-short recording method as a valuable tool for autonomic assessment. However, the minimum time-epoch to obtain a reliable record for all HRV domains (time, frequency, and Poincare geometric measures), as well as the effect of respiratory rate on the reliability of these indices remains unknown. METHODS: Twenty volunteers had their HRV recorded in a seated position during spontaneous and controlled respiratory rhythms. HRV intervals with 1, 2, and 3 min were correlated with the gold standard period (6-min duration) and the mean values of all indices were compared in the two respiratory rhythm conditions. RESULTS: rMSSD and SD1 were more reliable for recordings with ultra-short duration at all time intervals (r values from 0.764 to 0.950, p < 0.05) for spontaneous breathing condition, whereas the other indices require longer recording time to obtain reliable values. The controlled breathing rhythm evokes stronger r values for time domain indices (r values from 0.83 to 0.99, p < 0.05 for rMSSD), but impairs the mean values replicability of domains across most time intervals. Although the use of standardized breathing increases the correlations coefficients, all HRV indices showed an increase in mean values (t values from 3.79 to 14.94, p < 0.001) except the RR and HF that presented a decrease (t = 4.14 and 5.96, p < 0.0001). CONCLUSION: Our results indicate that proper ultra-short-term recording method can provide a quick and reliable source of cardiac autonomic nervous system assessment.

Long-Term Regular Eccentric Exercise Decreases Neuropathic Pain-like Behavior and Improves Motor Functional Recovery in an Axonotmesis Mouse Model: the Role of Insulin-like Growth Factor-1.

Although training programs with regular eccentric (ECC) exercise are more commonly used for improving muscular strength and mobility, ECC exercise effects upon functional recovery of the sciatic nerve has not yet been determined. After sciatic nerve crush, different mice groups were subjected to run on the treadmill for 30 min at a speed of 6, 10, or 14 m/min with - 16° slope, 5 days per week, over 8 weeks. During the training time, neuropathic pain-like behavior (mechanical and cold hyperalgesia) was assessed and functional recovery was determined with the grip strength test and the Sciatic Functional and Static indexes (SFI and SSI). After 9 weeks, triceps surae muscle weight and morphological alterations were assessed. Tumor necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß), interleukin-4 (IL-4), interleukin-1Ra (IL-1Ra), insulin-like growth factor-1 (IGF-1) levels, and markers pro- and anti-inflammatory and regeneration, respectively, were quantified in the muscle and sciatic nerve on day 14 post-crushing. Exercised groups presented less neuropathic pain-like behavior and better functional recovery than non-exercised groups. Biochemically, ECC exercise reduced TNF-α increase in the muscle. ECC exercise increased sciatic nerve IGF-1 levels in sciatic nerve crush-subjected animals. These findings provide new evidence indicating that treatment with ECC might be a potential approach for neuropathy induced by peripheral nerve injury.