Effects of the carrier frequency of interferential current on pain modulation and central hypersensitivity in people with chronic nonspecific low back pain: A randomized placebo-controlled trial.

BACKGROUND: Interferential current (IFC) is commonly used for pain relief, but the effects of carrier frequency of the current and its action on pain mechanisms remain unclear. This randomized placebo-controlled trial tested the effects of IFC in people with chronic nonspecific low back pain. METHODS: One hundred and fifty participants were randomly allocated into three groups: 1 kHz, 4 kHz and placebo. The primary outcomes were pain intensity at rest in the first session (immediate effect of the IFC), after 12 sessions, 4 months after randomization (follow-up) and during movement (first and last session). The secondary outcomes were disability, global perceived effect, functional performance, discomfort caused by the IFC, use of analgesics and physiological measures of pain. RESULTS: Only during the first session, there was a significant decrease in pain intensity in the active groups. However, there were no differences in the improvement of pain at rest or during movement in the active groups compared to the placebo group in the remaining sessions. The frequency use of analgesics was significantly decreased in the active groups. For pain physiology measures, there was a significant increase in pressure pain thresholds in both active groups compared to the placebo group and a reduction in the temporal summation in the 1 kHz group compared to the other groups. CONCLUSIONS: These results suggest that although the IFC has changed some physiological mechanisms of pain and showed decrease frequency use of pain medication, there was no change in the primary aim, pain intensity. WHAT DOES THIS STUDY ADD?: The interferential current (IFC) presented advantages in the physiological measures of pain and showed decrease frequency use of pain medication. Future studies should investigate analgesic intake with IFC treatment.

Effects of high-intensity intermittent training on carnitine palmitoyl transferase activity in the gastrocnemius muscle of rats

We examined the capacity of high-intensity intermittent training (HI-IT) to facilitate the delivery of lipids to enzymes responsible for oxidation, a task performed by the carnitine palmitoyl transferase (CPT) system in the rat gastrocnemius muscle. Male adult Wistar rats (160-250 g) were randomly distributed into 3 groups: sedentary (Sed, N = 5), HI-IT (N = 10), and moderate-intensity continuous training (MI-CT, N = 10). The trained groups were exercised for 8 weeks with a 10% (HI-IT) and a 5% (MI-CT) overload. The HI-IT group presented 11.8% decreased weight gain compared to the Sed group. The maximal activities of CPT-I, CPT-II, and citrate synthase were all increased in the HI-IT group compared to the Sed group (P < 0.01), as also was gene expression, measured by RT-PCR, of fatty acid binding protein (FABP; P < 0.01) and lipoprotein lipase (LPL; P < 0.05). Lactate dehydrogenase also presented a higher maximal activity (nmol·min-1·mg protein-1) in HI-IT (around 83%). We suggest that 8 weeks of HI-IT enhance mitochondrial lipid transport capacity thus facilitating the oxidation process in the gastrocnemius muscle. This adaptation may also be associated with the decrease in weight gain observed in the animals and was concomitant to a higher gene expression of both FABP and LPL in HI-IT, suggesting that intermittent exercise is a "time-efficient" strategy inducing metabolic adaptation.

Effects of high-intensity intermittent training on carnitine palmitoyl transferase activity in the gastrocnemius muscle of rats.

We examined the capacity of high-intensity intermittent training (HI-IT) to facilitate the delivery of lipids to enzymes responsible for oxidation, a task performed by the carnitine palmitoyl transferase (CPT) system in the rat gastrocnemius muscle. Male adult Wistar rats (160-250 g) were randomly distributed into 3 groups: sedentary (Sed, N = 5), HI-IT (N = 10), and moderate-intensity continuous training (MI-CT, N = 10). The trained groups were exercised for 8 weeks with a 10% (HI-IT) and a 5% (MI-CT) overload. The HI-IT group presented 11.8% decreased weight gain compared to the Sed group. The maximal activities of CPT-I, CPT-II, and citrate synthase were all increased in the HI-IT group compared to the Sed group (P < 0.01), as also was gene expression, measured by RT-PCR, of fatty acid binding protein (FABP; P < 0.01) and lipoprotein lipase (LPL; P < 0.05). Lactate dehydrogenase also presented a higher maximal activity (nmol·min(-1)·mg protein(-1)) in HI-IT (around 83%). We suggest that 8 weeks of HI-IT enhance mitochondrial lipid transport capacity thus facilitating the oxidation process in the gastrocnemius muscle. This adaptation may also be associated with the decrease in weight gain observed in the animals and was concomitant to a higher gene expression of both FABP and LPL in HI-IT, suggesting that intermittent exercise is a "time-efficient" strategy inducing metabolic adaptation.

Exercise training reduces PGE2 levels and induces recovery from steatosis in tumor-bearing rats.

The effects of endurance training on PGE (2) levels and upon the maximal activity of hepatic carnitine palmitoyltransferase (CPT) system were studied in rats bearing the Walker 256 carciosarcoma. Animals were randomly assigned to a sedentary control (SC), sedentary tumor-bearing (ST), exercised control (EC), and as an exercised tumor-bearing (ET) group. Trained rats ran on a treadmill (60% VO (2) max) for 60 min/day, 5 days/week, for 8 weeks. We examined the mRNA expression (RT-PCR) and maximal activity (radioassay) of the carnitine palmitoyltransferase system enzymes (CPT I and CPT II), as well as the gene expression of fatty-acid-binding protein (L-FABP) in the liver. PGE (2) content was measured in the serum, in tumor cells, and in the liver (ELISA). CPT I and CPT II maximal activity were decreased (p<0.01) in ST when compared with SC. In contrast, serum PGE (2) was increased (p<0.05) in cachectic animals as compared with SC. In the liver, PGE (2) content was also increased (p<0.05) when compared with SC. Endurance training restored maximal CPT I and CPT II activity in the tumor-bearing animals (p<0.0001). Exercise training induced PGE (2) levels to return to control values in the liver of tumor-bearing training rats (p<0.05) and decreased the eicosanoid content in the tumor (p<0.01). In conclusion, endurance training was capable of reestablishing liver carnitine palmitoyltransferase (CPT) system activity associated with decreased PGE (2) levels in cachectic tumor-bearing animals, preventing steatosis.

Deleteriuos effects of immobilization upon rat skeletal muscle: role of creatine supplementation.

AIM: The aim of the study was to investigate the impact of creatine feeding (5 g kg(-1) body weight day(-1)) upon the deleterious adaptations in skeletal muscle induced by immobilization. METHODS: Male Wistar rats were submitted to hind limb immobilization together with three dietary manipulations: control, supplemented with creatine for 7 days (along with immobilization) and supplemented with creatine for 14 days (7 days before immobilization and together with immobilization). Muscle weight (wet/dry) was determined in the soleus (SOL) and gastrocnemius (GAS). The analysis of lean mass was performed by DEXA and myosin heavy chain (MHC) distribution by SDS-PAGE. RESULTS: After 14 days of creatine loading, immobilized SOL and GAS total creatine content were increased by 25% and 18%, respectively. Regardless of dietary manipulation, the immobilization protocol induced a decrease in the weight of SOL and GAS (P < 0.001). However, creatine feeding for 14 days minimized mass loss in the SOL and GAS (P < 0.05). Our findings also indicate that creatine supplementation maximizes the expected slow-to-fast MHC shift driven by immobilization (P < 0.05). CONCLUSIONS: Previous creatine supplementation attenuates muscle wasting induced by immobilization. This effect is associated with the increment of intramuscular creatine content.

Relação entre enteroparasitoses, região ungueal e mãos contaminadas, em crianças e adolescentes da Instituição Filantrópica de Marília / Relationship between intestinal parasitesm, nail region and contaminated hands in children and adolescents from the Instituição Filantrópica de Marília

Foram analisadas amostras de fezes, material da região ungueal e a água após a lavagem das mãos de 58 crianças e adolescentes, entre 12 a 17 anos de idade, da Instituição Filantrópica de Marília, no período de 01 de agosto a 30 de setembro de 1988. Dos 58 pacientes analisados, 17 (29,3%) não apresentaram nenhum tipo de infecção parasitária; 41 (70,7%) apresentaram-se parasitados por protozoários com a prevalência de 35,1% do tipo Giardia lamblia em 5 (11,8%) e Entamoeba coli em 10 (23,3%); os demais, ou seja, 64,9% apresentaram-se parasitados por helmintos do tipo Ascaris lumbricoides em 10 (23,3), Ancilostomideos em 3 (8,3%) e Hymenolepis nana em 13 (33,3%). Diante dos resultados obtidos, pode-se verificar que o foco das infecções apresentadas, não teve correlação com a região ungueal ou com as mãos contaminadas, uma vez que os cistos, larvas e ovos pesquisados foram encontrados apenas nas fezes analisadas.