Synthesis, characterization, and antibacterial effect of St. John's wort oil loaded chitosan hydrogel.

Hydrogels prepared with natural and synthetic polymers were found to be applicable for the development of resistance against some Gram positive and negative bacterial species. Numerous studies have shown that chitosan polymers can be advantageous to be used in medicine due to their high antibacterial activity. In this study, biocompatible yellow cantorone oil doped hydrogels (chitosan/poly(vinyl alcohol) based) with antimicrobial properties were synthesized. The structural, morphological, swelling and mechanical properties of these biocompatible hydrogels prepared by double crosslinking were investigated and characterized. FTIR spectroscopy showed the appearance of new imine and acetal bonds due to both covalent cross-linking. In vitro cytotoxicity evaluation revealed that hydrogels showed weak cytotoxic effect. In the antimicrobial evaluation, it was determined that the hydrogel containing only chitosan showed better antimicrobial effect against Escherichia coli, Pseudomonas auriginosa, Staphylococcus aureus and Enterococcus faecalis bacteria than the one containing St. John's Wort oil. The antibacterial effect of polyvinyl alcohol/chitosan hydrogel was low. In our wound healing study, chitosan hydrogel loaded with yellow St. John's Wort oil was more effective in reducing wound size.

Unusual response to His-refractory atrial premature complex: What is the mechanism?

A 32-year-old woman underwent radiofrequency catheter ablation of narrow QRS tachycardia that was terminated with intravenous adenosine.

Medical ozone therapy reduces shock wave therapy-induced renal injury.

OBJECTIVES: Extracorporeal shock wave (ESW) lithotripsy is the preferred treatment modality for uncomplicated kidney stones. More recently free oxygen radical production following ESW application has been considered to be crucial in shock wave-induced renal damage. It has been shown that ozone therapy (OT) has ameliorative and preventive effects against various pathological conditions due to increased nitro-oxidative stress. In current study, we aimed to evaluate the efficacy of OT against ESW-induced renal injury. METHODS: Twenty-four male Sprague-Dawley rats were divided into three groups: sham-operated, ESW, and ESW + OT groups. All groups except sham-operated group were subjected to ESW procedure. ESW + OT group received 1 mg/kg/day of oxygen/ozone mixture intraperitoneally at 2 h before ESW, and OT was continued once a day for consecutive three days. The animals were killed at the 4th day, and kidney tissue and blood samples were harvested for biochemical and histopathologic analysis. RESULTS: Serum ALT and AST levels, serum neopterin, tissue nitrite/nitrate levels, and tissue oxidative stress parameters were increased in the ESW group and almost came close to control values in the treatment group (p < 0.05, ESW vs. ESW + OT). Histopathological injury scores were significantly lower in treatment group than the ESW group (p < 0.05, ESW vs. ESW + OT). Immunohistochemical iNOS staining scores in ESW group were higher than those of sham-operated group (p < 0.05, ESW vs. sham-operated), iNOS staining scores in OT group were significantly lower than the ESW group (p < 0.05, ESW + OT vs. ESW). CONCLUSION: OT ameliorates nitro-oxidative stress and reduces the severity of pathological changes in the experimental ESW-induced renal injury of rat model.

Effects of Hyperbaric Oxygen and Preconditioning on Wound Healing in Colonic Anastomoses.

AIM: The purpose of this study was to evaluate the effects of hyperbaric oxygen (HBO) and HBO preconditioning (pre-HBO) on experimental wound healing and tensile strength in the colonic anastomosis of rats. MATERIALS AND METHODS: A total of 21 Sprague-Dawley rats were divided into three random groups of equal numbers: sham operation, pre-HBO, and HBO. Sham group was given standard left colon resection and end-to-end anastomosis; pre-HBO group received HBO as one dose + colonic resection + anastomosis; HBO group was given colonic resection + anastomosis + HBO. HBO was administrated at 24-hr intervals and relaparatomy was performed on the fifth day. Malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), interleukin (IL)-10, IL-6, tumor necrosis factor-alpha (TNF-α), and hydroxy (OH)-proline levels and anastomotic burst pressure were evaluated. RESULTS: Burst pressure and OH-proline levels markedly increased in the HBO group compared with the sham and pre-HBO groups. When compared with the sham group, MDA and MPO levels were significantly decreased in the HBO and pre-HBO groups. In contrast to these findings, SOD and GSH-Px levels were increased in the HBO group as compared with the sham and pre-HBO groups. TNF-α, IL-6, and IL-10 values were detected at low levels in the HBO group as compared with other groups. CONCLUSIONS: HBO administration accelerated wound healing and strengthened the anastomotic tissue. In the light of these results, the HBO administration has beneficial effects and contributed to wound healing in colonic anastomosis. But, as expected, pre-HBO did not alter the results significantly.

Histomorphometric and microtomographic evaluation of the effects of hyperbaric oxygen and systemic ozone, used alone and in combination, on calvarial defect healing in rats.

PURPOSE: The aim of this study was to compare the efficacy of hyperbaric oxygen and systemic ozone, used separately and in combination, on the healing of bone defects. MATERIAL AND METHODS: Sixty male Wistar rats were divided into 4 groups (n = 15) according to treatment (control, hyperbaric oxygen [HBO], ozone [O], and HBO plus O [HBO-O]) and divided further into 3 subgroups according to day of sacrifice (postsurgical days 5, 15, and 30). Surgery was performed under general anesthesia to create a critical-size bone defect (5 mm in diameter) in the cranium. After sacrifice, microtomographic images of all samples were recorded, and histomorphometric analysis was performed. RESULTS: Histologic and radiologic measurements showed that the values of all experimental groups were higher than those of the control group. Histologic scores for all experimental groups were statistically higher than those for the control group day 30 (O, P = .045; HBO, P = .049; HBO-O, P = .042). Histologic scores also were statistically higher for the HBO group on day 5 (P = .045) and day 15 (P = .009) compared with the control group. Microtomographic scores were higher for the experimental groups than for the control group, with statistically significant differences for group O on day 5 (P = .033) and day 30 (P = .0045) and for group HBO on day 15 (P = .005). Histologic and radiologic analyses showed positive correlations. CONCLUSION: Within the limitations of this study, the use of hyperbaric oxygen and ozone, separately and in combination, were shown to be effective in increasing bone healing. Combined usage was no more effective in stimulating bone healing than separate usage.

A new utilization area for hyperbaric oxygen? Improving quality of stored blood.

BACKGROUND/AIM: Since blood bags have the ability for diffusion of gases, we investigated whether hyperbaric oxygen (HBO) exposure affects several vital parameters of stored blood. MATERIALS AND METHODS: Bloods obtained from the same persons were used as both control and HBO groups and stored in pediatric bags with citrate-phosphate-dextrose solution. HBO administration was performed at 2.5 atm for 90 min, started 1 day after blood collection and repeated every 2 days for a total of 10 times. The study was terminated on the 21st day. Complete blood count, glucose, pH, and osmotic fragility values were measured every week. RESULTS: Glucose and pH levels decreased in stored blood. In the HBO-exposed group, these decreases were less than in the control. In addition, mean corpuscular and platelet volumes tended to increase during storing process, but with HBO, these indexes remained lower, near physiologic levels. Another interesting finding of the study was the relative stable osmotic fragility ratio in the HBO group compared to the control blood. CONCLUSION: HBO exposure has positive effects on pH, stability of erythrocytes, and energy source (glucose) of the medium. Thus, we concluded that HBO may be a useful application for life and quality of stored blood.

Report: investigation of anti-cancer effects of cherry in vitro.

Cherry (Prunus Cerasus) is still one of the most popular preserve in Turkish cuisine. Cherry has been traditionally used for the treatment of inflammatory-related symptoms. Recent researches have proved that cherry is a valuable natural source of some important bioactive compounds in human health preservation. Evidence suggests that, cherry consumption may decrease the risk of chronic diseases and cancer. The aim of the present study was to determine the effects of cherry on breast cancer cells lines, asymmetric dimethylarginine (ADMA) level and certain multidrug-resistant bacteria. The cancer cell proliferation activity and analysis of apoptotic-necrotic cells was evaluated by using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and scoring of apoptotic cell nuclei. Measurement of ADMA and the minimum inhibitory concentration was accomplished by HPLC and the micro dilution broth method. The results showed that, extracts of cherry exhibit anti-proliferative activity in mammary adenocarcinoma (MCF-7) & mouse mammary tumor cell (4T1) breast cancer cells lines as well as induction of apoptosis, lower ADMA concentrations in cell cultures treated with cherry extract and antibacterial effects against certain multidrug-resistant bacteria in vitro. These findings may open new horizons for traditional anti-inflammatory product as prophylactic-therapeutic agent from cancer, cardiovascular diseases and multidrug-resistant infections.

An alternative noninvasive technique for the treatment of iatrogenic femoral pseudoaneurysms: stethoscope-guided compression.

OBJECTIVE: latrogenic femoral pseudoaneurysm is a well-known vascular access site complication. Many invasive and noninvasive techniques have been proposed for the management of this relatively common complication. In this study, we aimed to evaluate efficiency and safety of stethoscope-guided compression as a novel noninvasive technique in the femoral pseudoaneurysm treatment. METHODS AND RESULTS: We prospectively included 29 consecutive patients with the diagnosis of femoral pseudoaneurysm who underwent coronary angiography. Patients with a clinical suspicion of femoral pseudoaneurysm were referred to colour Doppler ultrasound evaluation. The adult (large) side of the stethoscope was used to determine the location where the bruit was best heard. Then compression with the paediatric (small) side of the stethoscope was applied until the bruit could no longer be heard and compression was maintained for at least two sessions. Once the bruit disappeared, a 12-hour bed rest with external elastic compression was advised to the patients, in order to prevent disintegration of newly formed thrombosis. Mean pseudoaneurysm size was 1.7 +/- 0.4 cmx 3.0 +/- 0.9 cm and the mean duration of compression was 36.2 +/- 8.5 minutes.Twenty-six (89.6%) of these 29 patients were successfully treated with stethoscope-guided compression. In 18 patients (62%), the pseuodoaneurysms were successfully closed after 2 sessions of 15-minute compression. No severe complication was observed. CONCLUSION: Stethoscope-guided compression of femoral pseudoaneurysms is a safe and effective novel technique which requires less equipment and expertise than other contemporary methods.

A walnut-enriched diet reduces the growth of LNCaP human prostate cancer xenografts in nude mice.

It was investigated whether a standard mouse diet (AIN-76A) supplemented with walnuts reduced the establishment and growth of LNCaP human prostate cancer cells in nude (nu/nu) mice. The walnut-enriched diet reduced the number of tumors and the growth of the LNCaP xenografts; 3 of 16 (18.7%) of the walnut-fed mice developed tumors; conversely, 14 of 32 mice (44.0%) of the control diet-fed animals developed tumors. Similarly, the xenografts in the walnut-fed animals grew more slowly than those in the control diet mice. The final average tumor size in the walnut-diet animals was roughly one-fourth the average size of the prostate tumors in the mice that ate the control diet.

Medical ozone therapy decreases postoperative uterine adhesion formation in rats.

PURPOSE: Various studies have been performed to find out novel treatment strategies to prevent postoperative adhesion formation. Ozone therapy (OT) is shown to reduce inflammation in several pathological conditions. Therefore, we aimed to evaluate the efficacy of OT in a rat model of experimental uterine adhesion (EUA). METHODS: Thirty female Wistar rats (200-250 g) were divided into three groups: sham, EUA and EUA+OT. EUA and EUA+OT groups were subjected to the postoperative adhesion procedure by bipolar coagulation on the uterine horns and corresponding pelvic sidewall parietal peritoneum. EUA+OT group received 0.7 mg/kg daily single dose for 3 days of ozone/oxygen mixture intraperitoneally after adhesion induction. All animals were killed on the 7th day and uterine adhesions were scored. Uterine tissues and peritoneal washing fluid were harvested for all analyses. RESULTS: Uterine malondialdehyde levels in the EUA group were significantly higher compared to the other groups. However, in the EUA group, uterine superoxide dismutase and glutathione peroxidase activities were lower than in other groups. Peritoneal fluid TNF-α levels were found to be significantly different for all groups (p < 0.001). Macroscopic total adhesion score was significantly higher in the EUA group compared to the other groups (p < 0.001). But, total score in the EUA+OT group was lower than in the EUA group (p = 0.006). CONCLUSIONS: Medical OT prevents postoperative uterine adhesions by modulating TNF-α levels and oxidative/antioxidative status in an experimental uterine adhesion model.

The effects of medical ozone therapy on renal ischemia/reperfusion injury.

INTRODUCTION: This study was designed to investigate the possible beneficial effects of medical ozone therapy (OT), known as an immunomodulator and antioxidant, on the renal function, morphology, and biochemical parameters of oxidative stress in kidneys subjected to ischemia/reperfusion injury (IRI). MATERIALS AND METHODS: Thirty male Sprague-Dawley rats were classified into three groups: control, renal IRI, and renal IRI + OT. The IRI group was induced by bilateral renal ischemia for 60 min, followed by reperfusion for 6 h. After reperfusion, the kidneys and blood of rats were obtained for histopathologic and biochemical evaluation. RESULTS: Renal IRI increased the tissue oxidative stress parameters (lipid peroxidation, protein oxidation, and nitrite plus nitrate) and decreased the antioxidant enzyme activities (superoxide dismutase and glutathione peroxidase). The serum neopterin levels showed correlation with oxidative stress parameters. All these parameters were brought to control values in the treatment group. Histopathologically, the kidney injury in the treatment group was significantly lesser than in the renal IRI group. CONCLUSIONS: Our results clearly showed that OT has beneficial effect to protect kidney against IRI. The serum neopterin levels might be used as a marker to detect the degree of renal IRI.

An evaluation of the effectiveness of pre-ischemic hyperbaric oxygen and post-ischemic aminoguanidine in experimental cerebral ischemia.

OBJECTIVE: To study the effects of pre-ischemic hyperbaric oxygen (HBO) and post-ischemic aminoguanidine (AG) on the infarct volume in permanent middle cerebral artery occlusion. METHODS: This study was approved by the Animal Experiments Ethics Committee of Gulhane Military Medical Academy, Ankara, Turkey and carried out from March 2006 to August 2006. A total of 28 Sprague-Dawley rats (200-320 g) were divided into 4 groups: control (K) group (n = 7); HBO group (n = 7); HBO + AG group (n = 7); and the AG group (n = 7). All rats underwent middle cerebral artery occlusion (MCAO) by subtemporal craniectomy, and permanent ischemia was created. A 2.8 atmospheric pressure of HBO was first applied to the HBO and HBO + AG groups for 45 minutes, and occlusion was created after 2 hours. In the HBO + AG group, intraperitoneal administration of AG hemisulfate (100 mg/kg) was started 6 hours after MCAO, and was continued twice a day for 3 days. RESULTS: The rate of infarction was found to be 22.2+/-3.1% in the control group, 16.1+/-2.7% in the HBO group, 15.2+/-1.9% in the HBO+AG group, and 14.4+/-3.3% in the AG groups. The rate of infarctions (therefore the volume of infarct) in the HBO, HBO + AG, and AG groups were found to be significantly decreased compared with the control group (p=0.002, p=0.001, and p=0.001). CONCLUSION: In permanent MCAO-induced ischemia in rats, HBO and AG were observed to have a lowering effect on the infarct volume, but no additive effect was observed. This situation can be explained by different mechanisms of action.

Evaluation of the oxidative effect of long-term repetitive hyperbaric oxygen exposures on different brain regions of rats.

Hyperbaric oxygen (HBO(2)) exposure affects both oxidative and antioxidant systems. This effect is positively correlated with the exposure time and duration of the treatment. The present study aims enlightening the relation of HBO(2) with oxidative/antioxidant systems when administered in a prolonged and repetitive manner in brain tissues of rats. Sixty rats were divided into 6 study (n = 8 for each) and 1 control (n = 12) group. Rats in the study groups were daily exposed 90-min HBO(2) sessions at 2.8 ATA for 5, 10, 15, 20, 30 and 40 days. One day after the last session, animals were sacrificed; their whole brain tissue was harvested and dissected into three different regions as the outer grey matter (cortex), the inner white matter and cerebellum. Levels of lipid peroxidation and protein oxidation and activities of superoxide dismutase and glutathione peroxidase were measured in these tissues. Malondialdehyde, carbonylated protein and glutathione peroxidase levels were found to be insignificantly increased at different time-points in the cerebral cortex, inner white matter and cerebellum, respectively. These comparable results provide evidence for the safety of HBO treatments and/or successful adaptive mechanisms at least in the brain tissue of rats, even when administered for longer periods.

The protective effects of ozone therapy in a rat model of acetaminophen-induced liver injury.

OBJECTIVES: Acetaminophen (APAP) overdose may cause acute liver injury. Ozone therapy (OT) is shown to reduce inflammation and necrosis in several entities. Thus, we have designed this study to evaluate the efficacy of OT in a rat model of APAP-induced liver injury. METHODS: Twenty-seven Sprague-Dawley rats were divided into three groups: sham, APAP and APAP+OT groups. In the APAP and the APAP+OT groups, liver injury was induced by oral administration of 1 g/kg APAP. The APAP+OT group received a single dose ozone/oxygen mixture (0.7 mg/kg) intraperitoneally 1h after APAP administration. All animals were killed at 24 hour after APAP administration. Blood samples and liver tissues were harvested to determine liver injury and oxidative stress parameters. Liver tissues and blood samples were obtained for biochemical and histopathological analyses. RESULTS: APAP administration caused necrosis in the liver after 24h. The degrees of liver necrosis of the APAP group were higher than the other groups (in both p<0.05, respectively). In the APAP+OT group, liver antioxidant enzymes activities were significantly higher than the APAP group (p<0.05), but were lower than the sham group (p<0.05). In the sham group, serum neopterin, a marker of cell-mediated immunity, concentrations (4.8±1.2 nmol/L) were lower than the APAP (14.7±1.4 nmol/L) and APAP+OT groups (7.5±2.4 nmol/L) (in both p<0.05, respectively). CONCLUSION: Our results showed that OT prevented liver necrosis in rats and reduced neopterin levels. These findings suggest that the use of OT as an adjuvant therapy which might improve the outcome in APAP induced liver injury.

Melatonin ameliorates necrotizing enterocolitis in a neonatal rat model.

INTRODUCTION: We designed the present study to evaluate the efficacy of melatonin (M) on the severity of necrotizing enterocolitis (NEC) in a neonatal rat model. MATERIALS AND METHODS: Immediately after birth, pups were weighed and randomized into 3 groups: NEC, NEC + M, and control. Necrotizing enterocolitis was induced by enteral formula feeding and exposure to hypoxia after cold stress at 4°C and oxygen. The NEC + M group received 10 mg/kg M daily for 3 days after the first day of the NEC procedure. The pups were killed on the fourth day, and their intestinal tissues were harvested for biochemical and histopathologic analysis. Blood samples were also obtained from the pups. RESULTS: The mortality rate and weight loss were highest in the NEC group. Malondialdehyde and protein carbonyl content were significantly increased, whereas superoxide dismutase and glutathione peroxidase were decreased in the NEC-treated pups. Melatonin prevented these changes, with these values being similar to control levels in the NEC + M group. Nitrate plus nitrite levels and serum tumor necrosis factor α and interleukin-1ß were increased in the NEC group, and histopathologic injury score in the NEC group was significantly higher than that in the NEC + M group. CONCLUSION: Melatonin significantly reduced the severity of NEC in our study.

Mercaptoethylguanidine attenuates caustic esophageal injury in rats: a role for scavenging of peroxynitrite.

INTRODUCTION: After ingestion of caustic material, tissue damage is caused by reactive oxygen species and reactive nitrogen species such as peroxynitrite. Mercaptoethylguanidine (MEG) is a well-known scavenger of peroxynitrite. This study was designed to determine whether MEG has a beneficial effect on caustic esophageal injury. MATERIALS AND METHODS: Forty-five rats were allocated into 3 groups: sham-operated, untreated, and treated groups. Caustic esophageal burn was created by instilling 15% NaOH in the distal esophagus. The rats were left untreated or treated with 10 mg/kg per day MEG intraperitoneally for 5 days. All rats were killed at 28 days. Efficacy of the treatment was assessed both histopathologically and biochemically. RESULTS: Of 15 rats, 6 (40%) died in the untreated group, and only 1 (7%) rat died in the treated group. The stenosis index (SI) and the histopathologic damage score were significantly lower in the MEG treatment group than the untreated group, which showed a correlation with tissue hydroxyproline level. In the untreated group, tissue oxidative stress parameters (malondialdehyde and protein carbonyl content) were significantly higher; and antioxidant enzyme activities (superoxide dismutase and glutathione peroxidase) were significantly lower. Administration of MEG ameliorated oxidative stress parameters and antioxidant enzyme activities. Urinary nitrate and nitrite levels increased in the treated and untreated groups in the first 3 days, suggesting increased nitrosative stress; but at the fourth day, nitrate and nitrite level reached control values in the treated group. CONCLUSION: Peroxynitrites play an important role in the healing process of caustic esophagitis. As a peroxynitrites scavenger, MEG potentially might be a useful adjuvant agent in the treatment of esophageal caustic burn by modulating the antioxidant defense mechanism.