Evaluation of the Antioxidant Activity of Root Extract of Pepper Fruit (Dennetia Tripetala), and It's Potential for the Inhibition of Lipid Peroxidation

Background

The antioxidant properties of ethanolic root extract of pepper fruit (Donnetia tripetala), and its effect on lipid peroxidation of some fresh beef tissues during frozen storage were investigated.

Materials and Methods

The antioxidant parameters were assessed using standard methods, while malondialdehyde levels of different fresh beef tissue sections treated with the extract prior to freezing, were estimated in a colorimetric reaction with thiobarbituric acid.

Results

The H₂O₂-scavenging ability of the extract was similar to that of ascorbic acid, with a maximum scavenging power of 55.61 ±4.98%, and an IC₅₀ value of 86µg/ml. The extract exhibited a concentration-dependent ferric ion-reducing power, although this was significantly lower relative to that of the ascorbic acid (p < 0.05). The total phenolic content was 212.5 ± 0.002 mg/g, while the nitric oxide-scavenging ability was 64.33 ± 0.2% after 150 min. The capacity of the extract to inhibit lipid peroxidation in frozen heart muscle slices was significantly higher than that of vitamin C (p < 0 .05), but comparable to vitamins C and E in frozen testes and kidney slices.

Conclusion

These results suggest that the root extract of D. tripetala is rich in antioxidants which can be applied to meat preservation during refrigerated storage.     

Antioxidant Activities In Vitro and Hepatoprotective Effects of Nelumbo Nucifera Leaves In Vivo

Background

Herbal medicines played a major role in the treatment of hepatic disorders, and a number of medicinal plants and their compounds were widely used for the treatment of these disorders, and oxidant stress injury was one of the mechanism of liver injury.

Materials and Methods

Antioxidant activity of Nelumbo nucifera leaves (NU) extracts was assayed by the methods of scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzo-thiazoline-6-sulfonicacid) (ABTS) radical and ferric reducing antioxidant power (FRAP) in vitro. By intraperitoneal injection carbon tetrachloride (CCl₄) to establish acute liver injury model in mice, the levels of Glutamic-pyruvic transaminase (GPT), glutamic-oxaloacetic transaminase (GOT), superoxide dismutase (SOD) and the content of and maleicdialdehyde (MDA) were detected to evaluate hepatoprotective effect of NU using corresponding test kit.

Results

EtOAC (NUEA) and n-BuOH extracts (NUBU) of N. nucifera leaves had good scavenging DPPH and ABTS radical activity and ferric reducing antioxidant power in vitro. DPPH radical scavenging activity and ferric reducing antioxidant power of NUEA (IC₅₀= 6.68±0.29 µg/mL, RACT₅₀=1749.82±67.03 µmol/g) and NUBU (IC₅₀= 4.61±0.01 µg/mL, RACT₅₀=1995.27±135.71 µmol/g ) were higher than that of BHT (IC₅₀=8.76±0.20 µg/mL, RACT₅₀=1581.68±97.41 µmol/g) and Dangfeiliganning (IC₅₀=28.06±0.17 µg/mL, RACT₅₀=1028.55±3.28 µmol/g). ABTS radical scavenging activity of NUEA (IC₅₀= 5.32±0.12 µg/mL) and NUBU (IC₅₀= 8.16±0.27 µg/mL) were higher than that of Dangfeiliganning (IC₅₀= 9.76±0.16 µg/mL). Thus, hepatoprotective effect of NUEA and NUBU was evaluated on CCl₄-induced acute liver injury mice. The results showed that the levels of GOT and GPT in each treatment group significantly decreased (p<0.001 and p<0.01, p<0.05, respectively) except for the group of NUEA (130.8 mg/kg) (p>0.05). The contents of malondialdehyde (MDA) in liver in groups of NUEA (523 mg/kg), NUBU (840.5 and 420.5 mg/kg, repectively) had significant decrease (p<0.001 and p<0.05, respectively), and the level of SOD in liver for each treatment group could significantly decrease (p<0.001, p<0.05, respectively).

Conclusion

NUEA and NUBU had significantly hepatoprotective effect for Calcium tetrachloride CCl₄-induced liver injury, which might be attributable to its antioxidant activity.     

In vivo hypoglycemic effect of methanolic fruit extract of Momordica charantia L

Background

Momordica charantia L. is a medicinal plant commonly used in the management of diabetes mellitus.

Objectives

We investigated the blood glucose lowering effect of the methanolic fruit extract of the Ugandan variety of M. charantia L. in alloxan-induced diabetic albino rats.

Methods

500g of M. charantia powder were macerated in methanol and the extract administered to two groups of alloxan-induced diabetic rats. The first group received 125mg/kg, the second 375mg/kg and a third group 7mg/kg of metformin. A fourth group received 1ml normal saline. Fasting blood glucose (FBG) levels were measured at 0.5,1,2,3,5,8 and 12 hours and compared using one-way ANOVA.

Results

There was an initial rise in FBG for 1 hour after administration of extracts followed by steep reductions. Significant reduction in FBG occurred at 2 hours for 125mg/kg of extract (−3.2%, 313±25.9 to 303±25.0mg/dL, p = 0.049), 375mg/kg of extract (−3.9%, 356±19.7 to 342±20.3mg/dL, p = 0.001), and metformin (−2.6%, 344±21.7 to 335±21.1mg/dL, p = 0.003) when compared to normal saline. The maximum percentage reduction in FBG by both extracts occurred between 3 and 12 hours post dose.

Conclusions

The methanolic fruit extract of M. charantia exhibits dose dependent hypoglycaemic activity in vivo.     

In Vitro Inhibition of Cytopathic Effect of Influenza Virus and Human Immunodeficiency Virus by Bamboo Leaf Extract Solution and Sodium Copper Chlorophyllin

Background

Although the link between oral and oropharyngeal health status and susceptibility to infection has long been recognized, there is a limit to the selection of antiseptics for oral care.

Methods

Madin-Darby canine kidney (MDCK) cells were exposed to influenza virus and cultured in the presence or absence of test reagents: bamboo leaf extract solution and sodium copper chrolophyllin. MDCK cells were pre-incubated with the reagents to assess the inhibitory activity at adsorption (viral attachment). Similarly, anti-HIV activity and the inhibitory mechanism at adsorption were assessed by MT-2 cell culture system. Mixture of HIV and bamboo leaf extract solution was fixed and examined by transmission electron microscopy.

Results

The 50% inhibitory concentration (IC₅₀) of bamboo leaf extract solution against influenza virus and the 50% cytotoxic concentration (CC₅₀) in MDCK cells of the solution lay between 0.0313–0.0625% and 0.5–1.0%. The solution inhibited the influenza virus adsorption at the concentration of 0.5% (P < 0.05). The values of IC₅₀ and CC₅₀ of sodium copper chlorophyllin lay between 50–100 µM and 200–400 µM, respectively. This inhibited the virus adsorption at 200 µM (P < 0.05). The bamboo leaf extract solution showed values of IC₅₀ against HIV and CC₅₀ in MT-2 cells at around 0.0313% and between 0.25–0.5%, respectively. This solution inhibited HIV adsorption at 1.25% (P < 0.05). The IC₅₀ and CC₅₀ of sodium copper chlorophyllin lay between 50–100 µM and 200–400 µM, respectively. Sodium copper chlorophyllin inhibited HIV adsorption at 2.5 mM (P < 0.05). HIV particles survived after the exposure to 0.5% bamboo leaf extract solution.

Conclusion

Sodium copper chlorophyllin exerted antiviral activities against influenza virus and HIV as the major ingredient of bamboo leaf extract solution by blocking adsorption. This mechanism of action is different completely from the one of povidone-iodine.     

In Vitro Antioxidant and In Vivo Hepatoprotective Activity of Leave Extract of Raphanus Sativus in Rats Using CCL4 Model

Background

Raphanus sativus is reported to have a variety of biological activities. This work screened the hepato-protective and antioxidant activity of ethanol (ERS), and aqueous (ARS), extracts of leaves of Raphanus sativus in Carbon tetrachloride (CCl₄), model in rats.

Material and Methods

The extracts were subjected to antioxidant tests (Total reducing power and Total phenolic content), and preliminary phytochemical screening. A pilot study was done on 100 and 300 mg/kg extracts, form which 300 mg was chosen for further experiments. The albino rats (200–250 grams), were divided into 5 groups of 6 animals each (n=6). There were three control groups comprising of normal control (normal saline −1ml/kg), negative control group (CCl₄ 1ml/kg in olive oil in a ratio of 1:1 v/v), and positive control group (Silymarin 50mg/kg). The Test drugs were given in a dose of 300 mg/kg for both ERS and ARS extract for 7 days. Biochemical parameters (AST, ALT, Alkaline phosphatase, Total Bilirubin), histo-pathological examination of liver and in vivo antioxidant tests [CAT, GSH and MDA] were done.

Results

The phytochemical study showed the presence of flavanoids, terpenoids, alkaloids, saponins and sterols. A dose dependent increase in the oxidative potential was observed in both the extracts with total phenolic content 70.1 and 44.4 GAE/g extract for ERS and ARS respectively. ERS 300mg/kg showed a significant (p<0.001) increase in levels of AST, ALT and alkaline phosphatase as compared to negative control (percentage hepatoprotection =45.3%) while ARS 300 mg/kg (p<.01) group showed 30% hepatoprotection. The GSH (p<0.001) and CAT (p<0.05) in ERS and ARS were significantly increased while MDA levels were decreased (P< 0.01), as compared negative control. The findings were confirmed histo-pathological examination.

Conclusion

The ethanol and aqueous extract of Raphanus sativus have partial hepatoprotection against CCl₄ toxicity.     

Antidiarrheal Mechanism and Ionic Profile of Carpolobia Lutea Ethanolic Stem-Bark Extract in Rats

Background

The stem-bark extract of Carpolobia lutea (Polygalaceae), used in ethno-medicine as anti-diarrhea was pharmacologically evaluated. This was the first report of assessment of the ethanolic stem extract (ESE), of C. lutea as anti-diarrhoeal agent in rats. The anti-diarrhoeal effects, acute toxicity and ionic profile are investigated and reported.

Materials and Methods

The acute toxicity was established using Lock''s method. The anti-diarrhoeal effects were demonstrated using castor oil-induced diarrheal and fluid accumulation and its effect on normal intestinal transit. The mechanism elucidated using yohimbine, isosorbide dinitrate, and diphenoxylate. The elemental and ionic profile of ESE was established using inductively coupled argon-plasma emission spectrometer and potentiometric titration respectively. The finger print of ESE was revealed by Jasco (Tokyo, Japan), HPLC and active compounds by phytochemical screening using standard procedure.

Results

The LD₅₀ obtained is 866.025 mg/kg (i.p). The doses of 43.3, 86.6, and 173.2 mg/kg of ESE showed inhibition of castor oil-induced diarrheal (p<0.05 –0.001). The most abundant cations in the extract are potassium and phosphorus (1.00 ±0.01 and 0.80 ± 0.030 mg/g respectively); while the most abundant anions are phosphate and sulphate (33.50±7.09 and 7.19±3.29 mg/g respectively). The HPLC fingerprint of ESE revealed UV spectra of biomolecules. Phytochemical screening revealed presence of saponins, polyphenols and glycosides.

Conclusion

These investigations indicate presence of bioactive and elemental substances which could play major role in diarrheal management. This investigation justifies the use of stem-bark of C. lutea in illicit gin (akpatashi), among the Effiks in Nigeria as antidiarrheal.     

Bioactivity-Guided Isolation of Anticancer Agents from Bauhinia Kockiana Korth

Background

Flowers of Bauhinia kockiana were investigated for their anticancer properties.

Methods

Gallic acid (1), and methyl gallate (2), were isolated via bioassay-directed isolation, and they exhibited anticancer properties towards several cancer cell lines, examined using MTT cell viability assay. Pyrogallol (3) was examined against the same cancer cell lines to deduce the bioactive functional group of the phenolic compounds.

Results

The results showed that the phenolic compounds could exhibit moderate to weak cytotoxicity towards certain cell lines (GI₅₀ 30 – 86 µM), but were inactive towards DU145 prostate cancer cell (GI₅₀ > 100 µM).

Conclusion

It was observed that pyrogallol moiety was one of the essential functional structures of the phenolic compounds in exhibiting anticancer activity. Also, the carboxyl group of compound 1 was also important in anticancer activity. Examination of the PC-3 cells treated with compound 1 using fluorescence microscopy showed that PC-3 cells were killed by apoptosis.     

Evaluation of Three Medicinal Plant Extracts Against Plasmodium Falciparum and Selected Microganisms

Background

A great revival of scientific interests in drug discovery has been witnessed in recent years from medicinal plants for health maintenance. The aim of this work was to investigate three Nigerian medicinal plants collected in Nigeria for their in vitro antiplasmodial and antimicrobial activities.

Materials and Methods

Extracts obtained from parts of Persea americana, Jatropha podagrica and Picralima nitida and their fractions were evaluated for in vitro antiprotozoal and antimicrobial activity.

Result

The methanol extract of P. nitida demonstrated activity against chloroquine-sensitive and chloroquine-resistant P. falciparum clones with IC₅₀ values of 6.3 and 6.0 µg/mL, respectively. Methanol and chloroform extracts of P. americana seed showed antifungal activity against Cryptococcus neoformans IC₅₀ less than 8 and 8.211 µg/mL respectively. Finally, the petroleum ether extract of P. americana had activity against methicillin-resistant Staphylococcus aureus (MRSA) with an IC₅₀ value of 8.7 µg/mL.

Conclusion

The study revealed the antibacterial and antiplasmodial activities of the plants extracts at the tested concentrations.     

Cyclooxygenase-2 and vascular endothelial growth factor in chronic hepatitis,cirrhosis and hepatocellular carcinoma

Background/Aims

Cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) are up-regulated in hepatocellular carcinoma (HCC). To investigate the levels of COX-2 and VEGF expression in chronic hepatitis (CH), cirrhosis, and HCC.

Methods

The immunohistochemical expressions of COX-2 and VEGF were evaluated in tissues from patients with CH (n=95), cirrhosis (n=38), low-grade HCC (LG-HCC; n=6), and high-grade HCC (HG-HCC; n=29).

Results

The COX-2 expression scores in CH, cirrhosis, LG-HCC, and HG-HCC were 3.3±1.9 (mean±SD), 4.2±1.7, 5.5±1.0, and 3.4±2.4, respectively (CH vs. cirrhosis, P=0.016; CH vs. LG-HCC, P=0.008; LG-HCC vs. HG-HCC, P=0.004), and the corresponding VEGF expression scores were 0.9±0.8, 1.5±0.7, 1.8±0.9, and 1.6±1.1 (CH vs. cirrhosis, P<0.001; CH vs. LG-HCC, P=0.011; LG-HCC vs. HG-HCC, P=0.075). Both factors were correlated with the fibrosis stage in CH and cirrhosis (COX-2: r=0.427, P<0.001; VEGF: r=0.491, P<0.001). There was a significant correlation between COX-2 and VEGF in all of the tissue samples (r=0.648, P<0.001), and between high COX-2 and VEGF expression scores and survival (COX-2: P=0.001; VEGF: P<0.001).

Conclusions

The expressions of both COX-2 and VEGF are significantly higher in cirrhosis and LG-HCC than in CH. High COX-2 and high VEGF expressions are associated with a high survival rate.     

Hepatoprotective Effect of Cymbopogon Citratus Aqueous Extract Against Hydrogen Peroxide-Induced Liver Injury in Male Rats

Background

Cymbopogon citratus (Poaceae) a tropical perennial herb plant that is widely cultivated to be eaten either fresh with food or dried in tea or soft drink has been reported to possess a number of medicinal and aromatic properties. This study aimed at evaluating the protective effects of C. citratus aqueous extract against liver injury induced by hydrogen peroxide (H₂O₂), in male rats.

Materials and Methods

Twenty-five rats were randomly divided into five different groups of five animals in each group; (1) Control. (2) Received H₂O₂ (0.5%) with drinking water. (3), and (4) received H₂O₂ and C. citratus (100 mg·kg⁻¹ b wt), vitamin C (250 mg·kg⁻¹ b wt) respectively. (5), was given C. citratus alone. The treatments were administered for 30 days. Blood samples were collected and serum was used for biochemical assay including liver enzymes activities, total protein, total bilirubin and malonaldehyde, glutathione in serum and liver homogenates. Liver was excised and routinely processed for histological examinations.

Results

C. citratus attenuated liver damage due to H₂O₂ administration as indicated by the significant reduction (p<0.05), in the elevated levels of ALT, AST, ALP, LDH, TB, and MDA in serum and liver homogenates; increase in TP and GSH levels in serum and liver homogenates; and improvement of liver histo-pathological changes. These effects of the extract were similar to that of vitamin C which used as antioxidant reference.

Conclusion

C. citratus could effectively ameliorate H₂O₂-induced oxidative stress and prevent liver injury in male rats.     

Cytoprotective and Antioxidant Effects of the Methanol Extract of Eremomastax Speciosa in Rats

Background

Ethno-botanical information shows that Eremomastax speciosa is used in the traditional management of various stomach complaints including gastro-duodenal ulcers.

Materials and Methods

In this study, we tested the cytoprotective potential of the whole plant methanol extract (100–200 mg/kg, p.o), against HCl/ethanol, absolute ethanol, cold/restraint stress rats, and pylorus legated rats pre-treated with indomethacin. The effects of the extract on gastric lesion inhibition, the volume of gastric juice, gastric pH, gastric acid output, mucus production and gastric peptic activity were recorded. Oxidative stress parameters were measured in blood and gastric tissue samples obtained from the animals in all the models tested.

Results

The extract significantly (p<0.05), reduced the formation of cold/restraint ulcers by (31–60%, inhibition), completely inhibited (100%) the formation of lesions induced by HCl/ethanol at the highest dose, but was less effective against absolute ethanol (22–46% inhibition). The extract (200 mg/kg), significantly reduced lesion formation (P<0.01), gastric acidity (P<0.01), and volume of gastric secretions (P<0.05), in the indomethacin/pylorus ligation model, and did not affect the activity of pepsin in gastric juice. Blood concentrations of antioxidant enzymes (catalase, SOD and GSH), increased significantly and MDA concentrations decreased in all models tested.

Conclusion

Cytoprotection by E. speciosa methanol extract was attributed to its ability to reduce acid secretion, and to enhance mucosal defence and in vivo antioxidant status.     

Experimental Study on the Optimization of Extraction Process of Garlic Oil and its Antibacterial Effects

Background

Garlic oil which is the main active constituent of garlic has a wide range of pharmacological activities, and a broad antibacterial spectrum. It also has a strong anti-cancer activity, and can significantly inhibit a variety of tumors such as liver cancer, gastric cancer and colon cancer. The objective is to study the extraction process of garlic oil and its antibacterial effects.

Materials and Methods

CO₂ Supercritical extraction was used to investigate the optimal processing conditions for garlic oil extraction; filter paper test and suspension dilution test were applied to determine the bacteriostatic action of garlic oil.

Results

In the CO₂ supercritical extraction experiment, factors influencing the yield of garlic oil were: extraction pressure > extraction temperature > extraction time in descending order. Range analysis showed that the optimal experimental conditions for CO₂ supercritical extraction of garlic oil were extraction pressure of 15 Mpa, temperature of 40 °C, and duration of 1 h. Different concentrations of garlic oil could all inhibit the growth of Staphylococcus aureus, Escherichia coli and Bacillus subtilis, suggesting that garlic oil has an antibacterial effect.

Conclusion

The optimal experimental conditions for CO₂ supercritical extraction of garlic oil were: extraction pressure of 15 Mpa, temperature of 40 °C, and duration of 1 h; garlic oil has an antibacterial effect.     

All-Trans Retinoic Acid Has a Potential Therapeutic Role for Diabetic Nephropathy

Purpose

The aim of this study was to examine the effects of all-trans retinoic acid (ATRA) on diabetic nephropathy.

Materials and Methods

We measured amounts of urinary albumin excretion (UAE) after administrating ATRA to Otsuka Long-Evans Tokushima Fatty (OLETF) rats. In order to understand the mechanism of action for ATRA, we administrated ATRA to examine its inhibitory action on the production of transforming growth factor-β₁ (TGF-β₁), protein kinase C (PKC), and reactive oxidative stress (ROS) in cultured rat mesangial cells (RMCs).

Results

After 16 weeks of treatment, UAE was lower in the ATRA-treated OLETF rats than in the non-treated OLETF rats (0.07±0.03 mg/mgCr vs. 0.17±0.15 mg/mgCr, p<0.01). After incubation of RMCs in media containing 30 or 5 mM of glucose, treatment with ATRA showed time- and dose-dependent decreases in TGF-β₁ levels and ROS. Moreover, ATRA treatment showed a dose-dependent decrease in PKC expression.

Conclusion

ATRA treatment suppressed UAE and TGF-β₁ synthesis, which was mediated by significant reductions in PKC activity and ROS production. Our results suggest that ATRA has a potential therapeutic role for diabetic nephropathy.     

Antioxidant Activity and Inhibitory Effect of Some Commonly Used Medicinal Plants Against Lipid Per-Oxidation in Mice Brain

Background

The present study compares the protective properties of aqueous extracts of six medicinal plants, Phyllanthus emblica, Terminalia chebula (black and yellow), Terminalia arjuna, Balsamodendron Mukul and Alium sativum against lipid per-oxidation in mice brain.

Methods

The antioxidant activities were analyzed by lipid per-oxidation assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay, total antioxidant activity and metal chelation.

Results

The extracts (fruits and bark) showed inhibition against thiobarbituric acid reactive species (TBARS) induced by pro-oxidant (10 µM FeSO4) in mice brain. Moreover, the free radical scavenging activities of the extracts was evaluated by the scavenging of DPPH radical (IC₅₀, 23.23±1.2 µg/ml (Phyllanthus emblica), 20.24±0.9 µg/ml (Terminalia chebula yellow) and 17.33±1.1 µg/ml (Terminalia chebula black), 19.44±0.45 µg/ml (Terminalia arjuna), 56.59±2.1 µg/ml (Balsamodendron Mukul) and < 200 µg/ml (Alium sativum).

Conclusion

The higher antioxidant and inhibitory effect of Terminalia chebula black in this study could be attributed to its significantly higher phenolic content, Fe(II) chelating ability, reducing ability and free radical scavenging activity. Therefore oxidative stress in brain could be potentially prevented by the intake of these plants.     

Antibacterial agents from the leaves of Crinum purpurascens herb (Amaryllidaceae)

Background

Typhoid fevers and urogenital infections continue to be serious health problems in developing countries. In our search for therapeutic agents from natural sources with potential for the treatment of typhoid fevers and urogenital infections, extract and compounds were obtained from Crinum purpurascens and tested.

Methods

Two alkaloids (4,5-ethano-9,10-methylenedioxy-7-phenanthridone or hippadine (1) and 4,5-ethano-9-hydroxy-10-methoxy-7-phenanthridone or pratorimine (2)) and one steroid (â-D-glucopyranoside of sitosterol (3)) were isolated from the CH₂Cl₂/MeOH (1:1) leaf extract of Crinum purpurascens and screened for antibacterial activity using both agar diffusion and broth dilution techniques.

Results

For the CH₂Cl₂/MeOH extract, the MIC values obtained were 3 mg/ml (against P. aeruginosa), 4 mg/ml (against E. coli, K. pneumoniae and S. aureus) and 6 mg/ml (against S. typhi and S. paratyphi B), whereas the MBC values varied between 7 and 12 mg/ml. For compound 1, the MIC values varied between 200 and 250 µg/ml, whereas the MBC value was 300 µg/ml against all the bacteria strains used. Compound 2 did not show any antimicrobial activity against these bacteria strains. For compound 3, the MIC values varied between 250 and 300 µg/ml, whereas the MBC values were 300 µg/ml (against S. typhi and S. paratyphi B) and > 300 µg/ml (against the other bacteria strains).

Conclusion

These data suggest that C. purpurascens leaf extract contains antibacterial agents which could be used in the treatment of typhoid fevers and urogenital infections.     

Muscle Activation and Movement Patterns During Prone Hip Extension Exercise in Women

Context:

The consistency of muscle activation order during prone hip extension has been debated.

Objective:

To investigate whether women use a consistent and distinguishable muscle activation order when extending the hip while prone and to explore the effects of verbal cues on muscle activation and movement.

Design:

Single-session, repeated-measures design.

Setting:

University laboratory.

Patients or Other Participants:

Eleven healthy women (age  =  27.7 ± 6.2 years [range, 22–37 years]).

Intervention(s):

We tested the participants under 3 conditions: no cues, cues to contract the gluteal muscles, and cues to contract the hamstrings muscles.

Main Outcome Measure(s):

We measured hip and knee angle and electromyographic data from the gluteus maximus, medial hamstrings, and lateral hamstrings while participants performed prone hip extension from 30° of hip flexion to neutral.

Results:

When not given cues, participants used the consistent and distinguishable muscle activation order of medial hamstrings, followed by lateral hamstrings, then gluteus maximus (195.5 ± 74.9, 100.2 ± 70.3, and 11.5 ± 81.9 milliseconds preceding start of movement, respectively). Compared with the no-cues condition, the gluteal-cues condition resulted in nearly simultaneous onset of medial hamstrings, lateral hamstrings, and gluteus maximus (131.3 ± 84.0, 38.8 ± 96.9, and 45.1 ± 93.4 milliseconds, respectively) (P > .059); decreased activation of the medial hamstrings (P < .03) and lateral hamstrings (P < .024) around the initiation of movement; increased activation of gluteus maximus throughout the movement (P < .001); and decreased knee flexion (P  =  .002). Compared with the no-cues condition, the hamstrings-cues condition resulted in decreased activation of the medial hamstrings just after the initiation of movement (P  =  .028) and throughout the movement (P  =  .034) and resulted in decreased knee flexion (P  =  .003).

Conclusions:

Our results support the contention that the muscle activation order during prone hip extension is consistent in healthy women and demonstrates that muscle timing and activation amplitude and movement can be modified with verbal cues. This information is important for clinicians using prone hip extension as either an evaluation tool or a rehabilitation exercise.     

Piper sarmentosum enhances fracture healing in ovariectomized osteoporotic rats: a radiological study

INTRODUCTION:

Osteoporotic fractures are common during osteoporotic states. Piper sarmentosum extract is known to possess antioxidant and anti-inflammatory properties.

OBJECTIVES:

To observe the radiological changes in fracture calluses following administration of a Piper sarmentosum extract during an estrogen-deficient state.

METHODS:

A total of 24 female Sprague-Dawley rats (200-250 g) were randomly divided into 4 groups: (i) the sham-operated group; (ii) the ovariectomized-control group; (iii) the ovariectomized + estrogen-replacement therapy (ovariectomized-control + estrogen replacement therapy) group, which was supplemented with estrogen (100 µg/kg/day); and (iv) the ovariectomized + Piper sarmentosum (ovariectomized + Piper sarmentosum) group, which was supplemented with a water-based Piper sarmentosum extract (125 mg/kg). Six weeks after an ovariectomy, the right femora were fractured at the mid-diaphysis, and a K-wire was inserted. Each group of rats received their respective treatment for 6 weeks. Following sacrifice, the right femora were subjected to radiological assessment.

RESULTS:

The mean axial callus volume was significantly higher in the ovariectomized-control group (68.2±11.74 mm³) than in the sham-operated, estrogen-replacement-therapy and Piper sarmentosum groups (20.4±4.05, 22.4±4.14 and 17.5±3.68 mm³, respectively). The median callus scores for the sham-operated, estrogen-replacement-therapy and Piper sarmentosum groups had median (range, minimum - maximum value) as 1.0 (0 - 2), 1.0 (1 - 2) and 1.0 (1 - 2), respectively, which were significantly lower than the ovariectomized-control group score of 2.0 (2 - 3). The median fracture scores for the sham-operated, estrogen-replacement-therapy and Piper sarmentosum groups were 3.0 (3 - 4), 3.0 (2 - 3) and 3.0 (2 - 3), respectively, which were significantly higher than the ovariectomized-control group score of 2.0 (1 - 2) (p<0.05).

CONCLUSION:

The Piper sarmentosum extract improved fracture healing, as assessed by the reduced callus volumes and reduced callus scores. This extract is beneficial for fractures in osteoporotic states.     

Perceptual Responses While Wearing an American Football Uniform in the Heat

Context:

The protective equipment worn during American football has been shown to increase thermal strain; however, the perception of this increased heat has not been examined.

Objective:

To evaluate perceptual responses of American football players while wearing different uniforms during exercise in the heat and to evaluate how these responses may be used to monitor athlete safety.

Design:

Randomized controlled trial.

Setting:

Human Performance Laboratory.

Patients or Other Participants:

Ten men with more than 3 years of competitive experience as football linemen (age  =  23.8 ± 1.3 years, height  =  183.9 ± 1.8 cm, mass  =  117.4 ± 3.5 kg, body fat  =  30.1% ± 1.7%) participated.

Intervention(s):

On 3 occasions in hot, humid (33°C, 48%–49% relative humidity) environmental conditions, participants completed 10 minutes of strenuous repetitive box lifting (RBL), 10 minutes of seated rest, and up to 60 minutes of treadmill walking. At each trial, they wore a different uniform condition: control (CON) clothing comprising shorts, socks, and sneakers; partial (PART) National Football League (NFL) uniform comprising the uniform without helmet or shoulder pads; or full (FULL) NFL uniform. Exercise, meals, and hydration status were controlled.

Main Outcome Measure(s):

Rectal temperature (T_re), skin temperature (T_sk), rating of perceived exertion (RPE), thermal perception (THM), perception of thirst (TST), and perception of muscle pain (MPN) were obtained for time points matched across trials.

Results:

Nineteen of the 30 trials ended before 60 minutes of treadmill walking as a result of participant exhaustion. Mean treadmill time was longer for the CON condition (51.7 ± 13.4 minutes) than for the PART (43.1 ± 15.6 minutes; t₉  =  3.092, P  =  .01) or the FULL (36.2 ± 13.2 minutes; t₉  =  4.393, P  =  .002) conditions. Neck and forearm T_sk increased between the initial time point and the end of exercise in the PART (33.6 ± 0.9°C and 35.0 ± 0.6°C, respectively; F_2,18  =  9.034, P < .001) and the FULL (33.4 ± 0.9°C and 35.2 ± 0.6°C, respectively; F_2,18  =  21.011, P  =  .002) conditions. Rate of T_re rise was greater in the FULL (0.042 ± 0.010°C/min) than in the PART (0.034 ± 0.006°C/min) condition (F_2,27  =  10.69, P  =  .04). We found a relationship at the post-RBL and final time points between RPE and THM (r  =  0.75, P < .001 and r  =  0.59, P < .001, respectively), RPE and TST (r  =  0.76, P < .001 and r  =  0.61, P < .001, respectively), and RPE and MPN (r  =  0.63, P < .001 and r  =  0.64, P < .001, respectively). The RPE was greater at the end of exercise in the PART (17 ± 2) and FULL (18 ± 1) conditions than in the CON (15 ± 3) condition (F_2,18  =  7.403, P  =  .005).

Conclusions:

Although no differences in perceptual scales existed between the PART and FULL conditions, the T_sk and rate of T_re increase differed, indicating that football athletes find it difficult to perceptually rate exercise conditions as potentially dangerous hyperthermia develops. In addition, correlations between the perceptual scales further defined perceptual responses during exercise in the heat.