Reflexes elicited by per-cutaneous stimulation of the medial and lateral ligaments of the knee

Joint disease is common in adults and in adolescents. It particularly affects the knee joints. In young people, joint disease has a number of causes including: genetic factors, defects in joint cartilage and sports related injuries. In particular, overtraining and traumatic injuries are common in many sports Participation in sports has expanded during the last two decades in many parts of the world. This has led to an increased number of injuries. Our knowledge of the role of ligaments in the control of movements and how they should be managed after injuries needs to expand as fast as participation rates. The aims of the current study were firstly, to investigate if reflexes can be elicited by electrical stimulation of ligaments. Secondly, to investigate if different muscles are affected differently by these reflexes. The final aim was to investigate if these reflexes can be modulated by posture or muscle activity. A total of 44 volunteers participated in a series of experiments. These experiments were designed to elicit reflexes following electrical stimulation of the collateral knee ligaments during sitting, standing and walking on treadmill. The reflexes were observed in averaged rectified electromyograms from Rectus Femoris, Vastus Medialis, Vastus Lateralis, Lateral and Medial Gastrocnemius and Soleus. Muscle activity was essential if reflexes were to be elicited. No reflexes were elicited in relaxed muscles. During the first series of experiments reflexes in Rectus Femoris, Vastus Lateralis and Vastus Medialis were investigated while the Reflexes were identified as changes in the averaged rectified electromyograms (EMG). The EMG in the immediate post stimulus period was compared with the pre-stimulus control. Inhibitory and excitatory reflexes were elicited following ligament stimulation in all three sets of experiments. The mean latency in quadriceps for early excitation was 57 +/- 6 msec and 67 +/- 10 msec for early inhibitions. The equivalent means were 70 +/- 6 msec and 77 +/- 6 msec for triceps. The shortest latency recorded in quadriceps was 46 msec. Longer latency reflexes were frequently observed. The mean latency in quadriceps for late excitation was 102 +/- 6 msec and 113 +/- 11 msec for late inhibitions. The equivalent means were 110 +/- 6 msec and 119 +/- 11 msec for triceps. There was no significant difference in the latencies of reflexes from MCL and LCL. The latencies in triceps were approximately 10 msec longer (90 msec for quadriceps a 100 msec for triceps) than those in quadriceps and this can be attributed to their longer conduction pathway. The reflexes were also recorded during gait. During walking, the latencies of both excitations and inhibitions were significantly longer than they were during sitting and standing. The mean latency of excitatory reflexes in Vastus Lateralis after LCL stimulation were 71 +/- 5 msec. For inhibitory reflexes the mean latency was 87 +/- 1 msec. The mean latency for excitation reflexes in Lateral Gastrocnemus was 82 +/- 2 msec and for inhibition reflexes was 94 +/- 3 msec. In each set of experiments the shortest latencies were consistent with slow group II or group III afferents excited by relatively strong stimulation. Control experiments using topical cutaneous anaesthesia minimised the possibility of cutaneous contributions to the observed reflexes. It is also possible that the electrical stimulation excited capsular afferents located close to the ligaments. This cannot be settled by the experiment reported in this thesis and the observed reflexes are best described as ligamento-muscular reflexes. These observed effects are consistent with recent results already published by Kim et al in 1995

Nanoparticle Synthesis, Applications, and Toxicity

Nowadays production of different nanoparticles (NPs) with plausible biomedical benefits is tremendously increasing. NPs are of great interest in drug delivery systems, drug formulation, medical diagnostic, and biosensor production. Aside from the importance of NPs in medicine, their negative side effects including potential cytotoxicity, inflammatory response induction, and drug interruption should be carefully considered. Several molecular and physicochemical mechanisms are involved in toxicity induction of NPs. Finding the negative effects of NPs on human tissues and investigation of their mechanism of action are a way for preventing the happening of unpleasant event. Here in this work, we would describe the main way of NP production with special attention to green NP production, and then their application in medical diagnosis and disease treatment would be explored. Also the main toxicity effects of NPs on different tissues would be explored, and the parameters affecting the quality of NPs and their corresponding biological properties would be highlighted

Variation in Weed Seed Fate Fed to Different Holstein Cattle Groups.

Weed seeds may maintain their viability when passing through the digestive tract of cattle and can be therefore dispersed by animal movement or the application of manure. Whether different cattle types of the same species can cause differential weed seed fate is largely unknown to us particularly under non-grazed systems similar to Holstein-Friesian dairy farming. We investigated the effect on the seed survival of four weed species in the digestive tracts of four groups of Holstein cattle: lactating cows, feedlot male calves, dry cows and growing heifers. The weed species used were Cuscuta campestris, Polygonum aviculare, Rumex crispus and Sorghum halepense. Cattle excretion was sampled for recovery and viability of seeds at four 24 hourly intervals after seed intake. The highest seed recovery occurred two days after seed intake in all cattle groups. Averaged over weed species, dry and lactating cows had the lowest and highest seed recovery of 36.4% and 74.4% respectively. No significant differences were observed in seed recovery of the four weed species when their seeds were fed to dry cows. Based on a power model fitted to seed viability data, the estimated time to 50% viability loss after seed intake, over all cattle groups ranged from 65 h (R. crispus) to 76 h (P. aviculare). Recovered seeds from the dung of feedlot male calves showed the highest mortality among cattle groups. Significant correlation was found between seed viability and ruminal pH (r = 0.86; P<0.05). This study shows that management programs aiming to minimize weed infestation caused by livestock should account for the variation amongst cattle groups in seed persistence. Our findings can be used as a guideline for evaluating the potential risk of the spread of weeds via the application of cattle manure

Efecte de la relació dels períodes de repòs molt breus en la testosterona i el cortisol durant l’exercici d’alta resistència en homes

La relació entre la concentració de testosterona i cortisol (relació T/C) se sol utilitzar com a índex del nivell d’esforç en l’entrenament esportiu. Els canvis que es produeixen en aquesta relació són responsables de moltes reaccions a l’exercici, com la hipertrofia i l’augment de força. L’objectiu d’aquesta recerca fou estudiar l’efecte de 4 sèries d’exercicis de pressió sobre banc i esquat fins a l’esgotament amb el 85% d’1 RM, sobre la relació de testosterona i cortisol d’homes entrenats en exercicis de resistència, utilitzant diferents intervals de repòs de 60 (P60), 90 (P90) i 120 (P120) segons. Deu homes entrenats en exercicis de resistència no competitiva (edat: 22 ± 2 anys; pes: 84 ± 8 kg; alçada: 178,5 ± 8,5 cm, amb un un any d’experiència com a mínim en exercicis de resistència [ER]), realitzaren protocols d’ER en sessions aleatòries, per separat. Es van extreure mostres de sang abans de l’exercici (Pre), immediatament després (Post) i 30 min després de finalitzar la sessió (30Post) per analitzar les concentracions sèriques de testosterona i de cortisol. Els resultats d’aquest estudi mostraren que la relació T/C durant l’interval P60 fou significativament més baixa en Post i 30Post en comparació amb el preexercici-exercici (p ≤ 0,05). La relació T/C després de l’exercici fou significativament més alta en P120 que en P60 i P90 (p ≤ 0,05), però no s’observaren diferències entre P60 i P90. Les dades indiquen que el període de repòs llarg entre sèries en ER fins a l’esgotament obtingué un augment major de la relació T/C que en el període de repòs breu. La millora de la relació T/C mitjançant períodes de repòs llarg entre sèries indica un augment de l’estat anabòlic fins a l’ER en homes entrenats en exercicis de resistència.La relació entre la concentració de testosterona i cortisol (relació T/C) se sol utilitzar com a índex del nivell d’esforç en l’entrenament esportiu. Els canvis que es produeixen en aquesta relació són responsables de moltes reaccions a l’exercici, com la hipertrofia i l’augment de força. L’objectiu d’aquesta recerca fou estudiar l’efecte de 4 sèries d’exercicis de pressió sobre banc i esquat fins a l’esgotament amb el 85% d’1 RM, sobre la relació de testosterona i cortisol d’homes entrenats en exercicis de resistència, utilitzant diferents intervals de repòs de 60 (P60), 90 (P90) i 120 (P120) segons. Deu homes entrenats en exercicis de resistència no competitiva (edat: 22 ± 2 anys; pes: 84 ± 8 kg; alçada: 178,5 ± 8,5 cm, amb un un any d’experiència com a mínim en exercicis de resistència [ER]), realitzaren protocols d’ER en sessions aleatòries, per separat. Es van extreure mostres de sang abans de l’exercici (Pre), immediatament després (Post) i 30 min després de finalitzar la sessió (30Post) per analitzar les concentracions sèriques de testosterona i de cortisol. Els resultats d’aquest estudi mostraren que la relació T/C durant l’interval P60 fou significativament més baixa en Post i 30Post en comparació amb el preexercici-exercici (p ≤ 0,05). La relació T/C després de l’exercici fou significativament més alta en P120 que en P60 i P90 (p ≤ 0,05), però no s’observaren diferències entre P60 i P90. Les dades indiquen que el període de repòs llarg entre sèries en ER fins a l’esgotament obtingué un augment major de la relació T/C que en el període de repòs breu. La millora de la relació T/C mitjançant períodes de repòs llarg entre sèries indica un augment de l’estat anabòlic fins a l’ER en homes entrenats en exercicis de resistència

Efectos de los períodos de reposo muy cortos en la relación de testosterona y cortisol durante ejercicios de alta resistencia en hombres

La relación entre la concentración de testosterona y cortisol (relación T/C) se suele utilizar como índice del nivel de esfuerzo en la práctica de ejercicio físico. Los cambios que se producen en esta relación son los responsables de varias reacciones al ejercicio, como la hipertrofia y el aumento de fuerza. Así, el objetivo de este estudio fue explorar el efecto de 4 series de press banca y sentadillas hasta el fallo con 85% de 1 RM utilizando diferentes intervalos de reposo de 60 (P60), 90 (P90) y 120 (P120) segundos sobre la relación de testosterona y cortisol en hombres entrenados en ejercicios de resistencia. Diez hombres entrenados en ejercicios de resistencia por placer (edad: 22±2 años; peso: 84±8kg; altura: 178,5±8,5; con 1 año de experiencia como mínimo en ejercicios de resistencia [ER]) realizaron protocolos de ER en sesiones aleatorias por separado. Se extrajeron muestras de sangre antes del ejercicio (pre), inmediatamente después (post) y 30min después del fin de la sesión (30-post) para analizar las concentraciones séricas de testosterona y cortisol. Los resultados de este estudio indicaron que la relación T/C en el intervalo P60 fue significativamente más baja en post y 30-post en comparación con la previa al ejercicio (p≤0,05). La relación T/C después del ejercicio fue significativamente más alta en P120 que en P60 y P90 (p≤0,05), pero no se observaron diferencias entre P60 y P90. Los datos indican que el período de reposo largo entre series en ER hasta el fallo obtuvo un aumento mayor de la relación T/C que el período de reposo corto. La mejora de la relación T/C mediante períodos de reposo largos entre series indica un aumento del estado anabólico hasta el ER en hombres entrenados en ejercicios de resistencia

Effects of very short rest periods on testosterone to cortisol ratio during heavy resistance exercise in men

The ratio between testosterone and cortisol concentration (Ts/Co ratio) is frequently used as an index of the stress level in exercise training. Changes in this ratio are responsible for several training responses such as hypertrophy and strength gain. So the purpose of this study was to investigate the effect of 4 sets of bench press and squat to failure with %85 of 1RM using different rest intervals of 60 (P60), 90 (P90) and 120 (P120) second on testosterone to cortisol ratio in resistance trained men. Ten recreationally resistance-trained men (age, 22±2 years; weight, 84±8kg; height, 178.5±8.5; at least 1 year of resistance exercise [RE] experience) performed RE protocols on randomized separating session. Blood draws occurred at pre-exercise (Pre); immediately after (Post) and 30min after the end of the session (30Post) for measurement serum testosterone and cortisol concentrations. The results of this study indicated that Ts/Co ratio in P60 trail was significantly lower at post and 30min post compare to pre-exercise (p≤0.05). The Ts/Co ratio at post exercise was significantly higher in P120 than P60 and P90 (p≤0.05), but no difference was found between P60 and P90. The data indicate that long rest period between sets in RE to failure resulted in a grater increase in Ts/Co ratio than short rest period between sets in RE. The enhanced in Ts/Co ratio by long rest period between sets, indicating an augmented anabolic state to RE in resistance trained men

Nanomedicine: The Novel Weapon against Parasitic Infections

Due to the side effects of drugs and resistance to the used chemicals in the treatment of tropical diseases such as malaria, leishmaniosis, trypanosomiasis and Schistosomiasis, which millions of people around the world are infected, nowadays nanomedicine usage with the production of nanofibers and nanoparticles (nanopowders, nanocrystal or nanocluster). The particles with a diameter of less than 100 nanometers is considered as a special treatment in parasitic diseases1,2. Due to the intracellular nature of some parasites, their treatment is a major challenge for researchers to develop new drugs. Findings show that Chitosan nanoparticles and metals such as silver, gold, and metal oxides have a lethal or inhibitory effect on various parasites, including giardiasis, leishmaniosis, malaria, or toxoplasma and insect larvae1.  The effects of drug release from chitosan nanofibers have also been performed in various external and internal evaluations on lesions caused by Leishmania major and the therapeutic effect of gold and silver nanoparticles on malaria and their concomitant use with bioresonance waves on leishmaniasis2,4. The main purpose of using nanoparticles is to use it as a drug delivery system and to release the drug agent in order to affect the specific site. Recently, the use of particle systems such as nanomedicine as a physical tool to improve the pharmacokinetic properties of various types of drug molecules in vivo is being developed1,4. The endocytic pathway transfers nanoparticles to the site of pathogens. The breakdown of these substances by lysosomal enzymes releases drugs into the phagocytic or lysosomal vesicle, or this process is released into the cytoplasm by a diffusion phenomenon. Specific transmission depends on the physical and chemical nature of the molecules1. In recent years, the use of nanoparticles for the treatment of parasitic diseases has considered, although limited research has conducted in this regard (Table 1). Finally, it can be concluded that according to recent findings on the inhibitory and long-term effects of nanofibers and nanoparticles on different parasites with less side effects than conventional drugs, more effective and less side effects drugs can be developed. Useful vaccines have also been developed to control parasitic diseases