Methylene Blue Group Research Articles

Influence of two photodynamic therapy sessions and different photosensitizers on the bond strength of glass-fiber posts in different regions of intraradicular dentin

Although photodynamic therapy associated with photosensitizers can promote microbial reduction, studies evaluating the consequences of two photodynamic therapy sessions associated with different photosensitizers on the bond strength of glass-fiber posts to endodontically treated intraradicular dentin are scarce. This in vitro study aimed to investigate the influence of two photodynamic therapy sessions using methylene blue or curcumin photosensitizers on the bond strength of glass-fiber posts to intraradicular dentin in different root thirds. Seventy-two teeth were divided into 9 experimental groups according to photosensitizer type, concentration and light-activation: Control - deionized water; Methylene blue 50 mg/L; Methylene blue 50 mg/L + laser; Methylene blue 100 mg/L; Methylene blue 100 mg/L + laser; Curcumin 500 mg/L; Curcumin 500 mg/L + LED; Curcumin 1000 mg/L; and Curcumin 1000 mg/L + LED. Push-out bond strength of the fiber posts to endodontically treated dentin was evaluated using a universal test machine (n = 8). Bond strength data underwent Kruskal-Wallis test, followed by Dunn test for comparison between treatments, and Friedman test for comparison between thirds (α = 0.05). Illustrative scanning electron microscopy images were obtained to qualify the failure mode. Curcumin at higher concentration, activated or not by blue LED, decreased the bond strength values in the apical region when compared with the control group (P < 0.05). There was no difference between two photodynamic therapy sessions using methylene blue photosensitizer (activated or not) and the control group regardless of concentrations and root canal depth evaluated (P > 0.05). Regarding intraradicular depth, the different thirds showed no statistical difference on bond strength values (P > 0.05). All experimental groups presented predominance of mixed-type failure, excepting the methylene blue group at higher concentration activated by red laser, and the curcumin photosensitizer at both concentrations activated by blue LED. Methylene blue at a 50 mg/L concentration can be applied in two PDT sessions, after biomechanical preparation and before glass-fiber post luting, as it presents no influence on root dentin bond strength in in vitro conditions.

Using methylene blue spray intraoperatively to perform safe thyroidectomy

BackgroundRecurrent laryngeal nerve (RLN) injury and hypoparathyroidism are serious complications following thyroidectomy. Minimizing these complications is important to avoid a destructive life-long handicap.AimOur goal was to decrease the incidence of intraoperative mishaps by spraying methylene blue dye on thyroid tissue and the tissues nearby.Patients and methodsThis is a prospective study that included 90 patients who underwent primary thyroid surgery for various thyroid diseases, with total thyroidectomy done in all. The patients were divided into two groups: methylene blue group included 45 patients who underwent surgery using methylene blue technique, and conventional group included 45 patients who underwent surgery using the conventional technique. Spraying of 0.5 ml of methylene blue stain (normal saline) (2 : 8) following superior pole ligation was done. Thyroid tissue of a lobe and perilobar area were exposed to the methylene blue dye spraying, with identification and evaluation of the RLN and parathyroid tissues.ResultsRLN and inferior thyroid artery stayed white in color in every case, but other tissues have been stained by blue color, with different times of fading out. Parathyroid glands stained for 3 min before fading out. Time for wash-out of thyroid gland was 15 min, whereas fading out time for other tissues, such as perithyroid tissues, tendinous, and lipoid structures was ∼25 min.ConclusionThis research aims to show the efficacy of methylene blue spraying as a safe procedure for identification of different important structures in close relation with the operative field such as RLN and parathyroid glands intraoperatively to do safe thyroidectomy.

Effect of Er:YAG laser irradiation using SWEEPS and PIPS technique on dye penetration depth after root canal preparation.

This study aimed to investigate the penetration depth of two different dyes after root canal preparation using PIPS and SWEEPS methods. A total of 60 single-rooted human teeth which were extracted for periodontal reasons were collected and stored in the sterile saline until using in the study. The crowns of the teeth were cut such that the remaining piece was 12 mm long. The root canals were prepared. Teeth were divided randomly into two initial groups (n = 30): indocyanine green solution (ICG) and methylene blue solution. Then, these teeth were divided into final subgroups (n = 10): Er:YAG laser irradiation with PIPS(photon-induced photoacoustic streaming) technique, Er:YAG laser irradiation with SWEEPS(shock-wave enhanced emission photoacoustic streaming) technique, and no irradiation. The penetration depth measurements were done by the stereo microscope in three zones of each specimen. The difference between ICG in the control group and PIPS and SWEEPS in the coronal area was not significant. In the middle section the difference between PIPS and the control group was marginally insignificant (P = 0.053). In the methylene blue group, PIPS had significantly higher penetration depth in the apical area compared to the control group (P = 0.004). In the middle section, both PIPS and SWEEPS showed significantly higher penetration than the control group. According to the results of this study, the laser has the potential to increase the penetration of methylene blue. Root canal preparation with the PIPS technique can increase the dye penetration. However, the SWEEPS technique and the conventional method have a similar outcome in terms of dye penetration.

Methylene blue usage for determining accessory artery ligation in donor kidneys.

Objectives. We present a technique for determining whether to ligate or preserve accessory arteries in donor kidneys before implantation. Methods. Forty-three living-related donor kidneys in patients from January 2014 to February 2018 at our institution were included, all of which had dual arteries without the same stem. Among them, 19 cases of accessory arterial blood supply were evaluated using methylene blue (MB) perfusion, and accessory arteries supplying less than 10% of the total MB perfusion volume were ligated. The other 24 cases were assessed using a conventional method in which arteries with diameters less than 2mm were ligated. The back-table surgical time, Doppler ultrasonography index, renal function and complications were compared between the 2 groups. Results. All patients underwent successful kidney transplantation. The back-table surgical time in the MB group was longer than that in the conventional group (42.70 ± 4.70min vs 34.64 ± 5.30min, P < .05). The serum creatinine level in the MB group was significantly lower than that in the conventional group 1month after the operation (103.15 ± 19.26μmol/L vs 119.17 ± 28.32μmol/L, P < .05). No differences in the Doppler ultrasonography index or postoperative complications were noted. Conclusions. MB perfusion provides an easy and effective method to make decisions regarding arterial ligation and helps preserve renal function without increasing the number of complications after transplantation.

The effect of dual-frequency ultrasound waves on B16F10 melanoma cells: Sonodynamic therapy using nanoliposomes containing methylene blue.

We investigated the effect of dual-frequency sonication on the viability of B16F10 melanoma cells in the presence of methylene blue (MB) encapsulated in nanoliposomes. Treatment protocols were studied: sonication groups (40kHz, 1MHz and dual-frequency), the same sonication groups with nanoliposomes containing MB, MB free and nanoliposomes containing MB groups, and so sham and control groups. The nanoliposomes were prepared by the lipid film hydration method. The cell viability of the different treatment groups was evaluated by the MTT assay. The dual-frequency protocols caused higher viability losses compared to the kHz and MHz sonications (P<.05). In presence of the nanoliposomes containing MB, dual frequency led to 6% and 3% viability for 600 and 1200seconds, respectively, while the corresponding values were 10% and 4% for the 40kHz protocols and 22% and 9% for the 1MHz, as compared to the control group (100%). The result of KI dosimetry showed that the cavitation activity of the dual-frequency protocol was about 1.23, as compared to sonication at 40kHz and 1MHz. Enhancement of inertial cavitation induction by dual-frequency sonication may be the primary effective mechanism, which causes increased sonochemical processes and drug release from nanocarriers.

The ameliorative effects of methylene blue on testicular damage induced by cisplatin in rats.

Cisplatin, a common chemotherapeutic drug, can induce testicular toxicity. Methylene blue, a potent antioxidant, can inhibit the generation of free radicals. This research aimed to study the protective effect of methylene blue against the cisplatin-induced toxicity of the reproductive system in rats. 35 male Wistar rats were divided into five groups: the control group, the cisplatin group (a single dose of 5mg/kg cisplatin), the low-dose and high-dose methylene blue+cisplatin (2 and 4mg/kg of methylene blue, respectively, for 7days) and the methylene blue group (4mg/kg of methylene blue, for 7days). The treatments were applied through intraperitoneal injection. Cisplatin treatment reduced the sperm parameters and serum testosterone levels significantly. Methylene blue treatment increased the sperm count (p<.001), viability (p<.001) and motility (p<.001) compared to the cisplatin group. The methylene blue group showed a significant increase in the levels of testosterone compared to the cisplatin group (p<.001) and reverted histopathological changes in cisplatin-treated groups. Immunohistochemical evaluation of the caspase-3 protein revealed that the treatment with methylene blue has significant anti-apoptotic effects on testicular tissue damage. In conclusion, methylene blue can attenuate the cisplatin-induced histological damages and improve the sperm parameters.

Methylene blue reduces incidence of early postoperative cognitive disorders in elderly patients undergoing major non-cardiac surgery: An open–label randomized controlled clinical trial

Study objectiveThe purpose of the present study was to investigate whether methylene blue (MB) could reduce the incidences of postoperative delirium (POD) and early postoperative cognitive dysfunction (POCD) in elderly patients undergoing major non-cardiac surgery. DesignProspective, randomized, open–label clinical trial. SettingUniversity-affiliated hospital. PatientsTwo hundred and forty-eight elderly patients scheduled for non-cardiac surgery. InterventionsElderly patients undergoing non-cardiac major surgery were randomly assigned to MB group (n = 124), who receiving intravenous infusion of 2 mg/kg MB within 60 min immediately after anesthetic induction, or control group (n = 124), who receiving equal volume saline in the same way. MeasurementsAll patients were evaluated with delirium and neuropsychological batteries before and after surgery, as well as perioperative adverse events. Two plasma biomarkers superoxide dismutase (SOD) and homocysteine (HCY) were measured pre- and post-operatively. Main resultsThere were total 39 cases(15.7%)experienced POD. The incidence of POD in MB group was significantly less than that in control group (7.3% vs. 24.2%, OR = 0.24, 95%CI: 0.11–0.53, p < 0.001). The incidence of early POCD at postoperative 7th day in MB group was also less than that in control group (16.1% vs. 40.2%, OR = 0.30, 95% CI: 0.16–0.57, p < 0.001). The adverse events were comparable in both groups. In addition, there was no significant correlation between POD/POCD and levels of SOD or HCY. ConclusionWe conclude that intraoperative intravenous 2 mg/kg MB could significantly reduce the incidences of POD and early POCD in elderly surgical patients, while not remarkably increase incidence of perioperative adverse events, suggesting MB may be clinically effective and safe for prevention of early postoperative neurocognitive disorders.

Influence of photodynamic therapy on bond strength and adhesive interface morphology of MTA based root canal sealer to different thirds of intraradicular dentin.

Photodynamic therapy (PDT) is used as an adjunct to endodontic treatment to enhance microbial reduction in the root canal system. However, studies evaluating the impact of PDT on the bond strength of the canal sealer to intraradicular dentin are scarce. Thus, this in vitro study aimed to evaluate the influence of photodynamic therapy with methylene blue (MB) photosensitizer (PS) on the bond strength and morphology of the interface between mineral trioxide aggregate (MTA) based endodontic sealer and different thirds of intraradicular dentin. Fifty-five bovine incisors were used to simulate experimental endodontic treatments. Biomechanical instrumentation was performed in all root canals and teeth were divided into 5 groups (n = 11): deionized water (control), methylene blue 50 mg/L (MB50WL), methylene blue 100 mg/L (MB100WL), methylene blue 50 mg/L + red laser (MB50L), and methylene blue 100 mg/L + red laser (MB100L). The push-out bond strength of canal sealer to intraradicular dentin was measured using a universal testing machine (n = 8). Representative scanning electron microscopy images were obtained to qualify the fracture patterns. Images of the adhesive interface morphology were obtained using confocal laser scanning microscopy (n = 3). The Kruskal-Wallis test was used to compare data on bond strength between groups, and the Friedman test between thirds (α = 0.05). When comparing root thirds for the MB group with the higher concentration activated by red laser, higher bond strength values was found for the apical third than for the middle third (P = 0.0302). MB in different concentrations, activated by red laser or not, had no influence on the bond strength of distinct thirds of the intraradicular dentin (P > 0.05). As for the adhesive interface morphology, the MB100L group showed a lower qualitatively sealer penetration into the intraradicular dentin. PDT with MB PS at 50 mg/L had no negative impact on the bond strength of MTA Fillapex canal sealer to intraradicular dentin, being a suitable antisepsis protocol for endodontic treatments.

Comparison of indocyanine green fluorescence and methylene blue dye in the detection of sentinel lymph nodes in breast cancer.

Previous studies have shown that sentinel lymph node biopsy (SLNB) can be successfully performed using methylene blue (MB); however, this method still has some drawbacks. Indocyanine green (ICG) fluorescence imaging, as a selective method, has the potential for guiding SLNB. This study aimed to compare the clinical sensitivity and efficacy between ICG and MB in SLNB in breast cancer. A prospective study of 70 patients with biopsy-proven invasive breast cancer was conducted. Under the guidance of ICG and MB, administered by injection, SLNs were examined and removed. The detection rates, total number of SLNs detected, mean number of SLNs detected, and number of positive SLNs were compared between ICG and MB. The SLN detection rate was 100% and 93% (65/70) for ICG and MB, respectively. More SLNs were detected in the ICG group (243) than in the MB group (169). The mean number of SLNs detected with ICG and MB was 3.5±1.73 and 2.4±1.49, respectively. Moreover, there was a statistically significant difference between the number of SLNs detected using the two methods (t=6.648, P<0.05). Additionally, SLN metastasis was detected in 18 patients using ICG and 14 patients using MB; these patients immediately underwent axillary lymph node dissection (ALND). No postoperative complications were reported. ICG demonstrated a higher detection rate and better accuracy, as well as a lower false negative rate, than MB in detecting SLNs in breast cancer. ICG has potential as an alternative tool that could be clinically applied to detect SLNs in breast cancer patients.

Comparison of indocyanine green and methylene blue use for axillary reverse mapping during axillary lymph node dissection.

Axillary reverse mapping (ARM) is a technique to identify arm lymphatic drainage during axillary lymph node dissection (ALND). This study compared the feasibility of ARM using indocyanine green (ICG) or methylene blue (MB), and accessed the oncologic safety of the procedure. Overall, 158 patients qualified for ALND were enrolled. The characteristics of ARM‐identified nodes were recorded with ICG (n = 78) or MB (n = 80) visualization. Fine‐needle aspiration cytology (FNAC) of the nodes were performed and validated by histologic analysis. The nodal identification rate in the ICG group significantly surpassed that of the MB group (87.2% vs 52.5%, P < .05) with fewer complications. Note that 10.9% of the patients had metastatic involvement of the ARM‐identified nodes. Also 80% of the positive nodes were found in areas B and D, while the ARM‐identified nodes mainly located in area A. All the 51 nodes diagnosed as negative of malignancy by FNAC were free of metastasis. Nodal metastasis was significantly correlated with extensive nodel involvement, advanced disease, and the characteristics of identified nodes. In conclusion, ICG appears superior to MB for ARM nodes identification. FNAC, together with the features of primary tumors and ARM nodes, can delineate which nodes could be preserved during ALND.

Efficacy of methylene blue in a murine model of amlodipine overdose.

Amlodipine overdoses have significant cardiac toxicity and are difficult to treat. Methylene blue has potential as a treatment for overdoses. A randomized controlled study of methylene blue as a treatment for amlodipine toxicity was conducted in C57Bl/6 mice. A baseline echocardiography was followed by gavage administration of amlodipine (90 mg/kg). Five minutes after gavage, animals received either vehicle solution (controls) or methylene blue (20 mg/kg) by intra-peritoneal injection. Animals were continuously monitored, and cardiac parameters were acquired every 15 min up to two hours. Only 50% of control animals survived to the two-hour endpoint compared to 83% that received methylene blue. Amlodipine delivery induced significant reduction in left ventricular ejection fraction (EF), fractional shortening (FS), stroke volume (SV), and cardiac output (CO) in the vehicle treated animals relative to animals in the treatment group (p < 0.05 vehicle versus Methylene blue for EF, FS, SV, CO, and HR). The amlodipine dose induced cardiotoxicity that were effects were more pronounced in the untreated group. 50% vehicle controls quickly progressed into heart failure (within 90 min of exposure) and did not survive the two h observation endpoint. Distinctly, only one animal from the Methylene blue treatment group did not survive (83% survival) the study. Additionally, the surviving animals from the Methylene blue group displayed significantly higher ejection fraction, fractional shortening, stroke volume, and cardiac output compared to vehicle group, indicating that methylene blue preserved cardiac function. In this mouse model of amlodipine overdose, methylene blue decreased cardiac toxicity.

Effect of photodynamic therapy on microleakage of class V composite restorations in primary teeth.

Photodynamic therapy (PDT) is a treatment by which, light sensitive chemicals are activated at a specific wavelength, generating reactive oxygen species which can be antimicrobial and assist in disinfection. However, the oxygen radicals may interfere with the bonding process. The purpose of this study was to assess the effect of PDT with different photosensitizers on microleakage of composite restorations. Seventhy-two primary teeth with sound labial/buccal and lingual surfaces were collected for this study. The teeth were randomly divided into four groups of control, PDT with indocyanine green, PDT with methylene blue, and PDT with toluidine blue. Next, the cavities were restored with composite resin. The specimens were stained with 0.5 % Fuchsine and sectioned. The specimens were observed under a microscope to determine the microleakage score. The microleakage was compared between the groups and between the occlusal and cervical walls in each group. Data were analyzed using SPSS version 25. According to the kruskal-wallis test, no significant difference was observed in microleakage between the groups in the occlusal wall (p = 0.859). However, there was a significant difference in the cervical wall between the control and toluidine blue (p = 0.019), and the control and methylene blue (p = 0.008) groups. The Wilcoxon test showed a significant difference in microleakage (p < 0.05) between the occlusal and cervical walls within each group. PDT may be used in cavities with enamel margins to decrease the microbial load and prevent secondary caries. PDT is not recommended for cavities with cementum margins. Alternatively, it can be performed with indocyanine green as photosensitizer in such cases.

The role of Intraoperative cholangiography (IOC) and methylene blue tests in reducing bile leakage after living donor hepatectomy

AimLiver transplantation remains the only curative treatment in end stage liver disease. Biliary complications remain the most common major morbidity causes in hepatic resection. We aimed to determine and eliminate the bile leakage in donor hepatectomy of LDLT. Material and methodsThis study was conducted retrospective and one center study. The study population included 110 consequential liver donors with major liver resection (more than three segments). The population was divided into three groups for data analyses. Primary study groups included 40 donors subjected to methylene blue test starting in April 2013 and 40 donors subjected to intraoperative cholangiography started in March 2014. ResultsA total of 110 liver donors (42.7% women) were included in the study. Postoperative biliary complications were less in methylene blue and intraoperative cholangiography (IOC) groups. Bile leakage was significantly higher in control group (23.3%) compared to methylene blue (5%) and IOC groups (2%) Average duration of hospital stay and duration of operation were significantly higher in control group compared to methylene blue and IOC groups. ConclusionIn our study we conducted to establish biliary leakage in living donor hepatectomy which intraoperative cholangiography test was used to determine. Many intraoperative methods have been introduced to prevent biliary leakage and development of complications. We have showed that IOC test used in the present study could be easily applied in both living liver donor hepatectomy and other major hepatectomy cases. IOC test reduced postoperative biliary leakage incidence and did not increase incidence of other complications.

Methylene Blue Does Not Improve Vasoplegia After Left Ventricular Assist Device Implantation

Vasoplegia is a frequent complication of left ventricular assist device (LVAD) implantation. We investigated the effectiveness of methylene blue (MB) for vasoplegia in LVAD recipients. Twenty-seven patients received MB for vasoplegia after LVAD implantation and met study criteria between March 2015 and May 2018. Propensity score inverse probability weighting identified 41 controls who did not receive MB for post-LVAD vasoplegia. Clinical outcomes were compared between control and MB groups and between patients who received doses during (n= 15) and after surgery (n= 12). Hemodynamics and vasopressor requirements were analyzed using analysis of covariance. Median total MB dose was 1.9 mg/kg (interquartile range, 1.2-2.2 mg/kg). Methylene blue recipients experienced a transient initial decline in norepinephrine requirement from 141 ng/kg per min (95% confidence interval [CI], 81-201 ng/kg per min) to 117 ng/kg per min (95% CI, 58-176 ng/kg per min; P= .022) and a delayed decline in vasopressin from 4.8 U/h (95% CI, 3.8-5.8 U/h) to 4.0 U/h (95% CI, 2.8-5.1 U/h) (P= .004). In-hospital mortality, postoperative complications, and end-organ dysfunction did not differ from those of controls. There were no observed differences in mean arterial pressure, vasopressor requirements, or outcomes between patients who received doses during or after surgery. Weighted overall mortality in the entire study cohort was 8.8%. Although MB may affect vasopressor requirements, clinical outcomes in vasoplegia after LVAD implantation did not improve and were not affected by the timing of administration.

In vitro study of photodynamic therapy with visible laser systems applied to fungal infections

Evaluate the “in vitro” effect of the 660-nm laser on the inactivation of planktonic cells of Candida albicans, by the application of 660-nm diode laser light (1) on its own and (2) together with photodynamic therapy using methylene blue. We will also compare the ability of microbial inactivation of the laser over octenidine dihydrochloride disinfectant. This study was conducted in a laminar flow cabinet with 4 groups, divided into two: no laser groups—C. albicans suspension in saline solution (Group 1) and C. albicans suspension, with octenidine dihydrochloride antimicrobial solution (Group 2); laser groups—C. albicans suspension, using a 660-nm diode laser with photodynamic therapy and methylene blue (Group 3), and C. albicans suspension, using a 660-nm diode laser without the presence of methylene blue as photosensitizer (PS) (Group 4). They were seeded in 96 wells where we applied laser light in different light conditions in order to get reliable results. The results of this study demonstrate that the application of a 660-nm laser, with and without the presence of a photosensitizer, showed microbial inhibition ability against Candida albicans. Photodynamic therapy using the methylene blue photosensitizer presented an antifungal effect against Candida albicans of 100% efficacy, similar to the results obtained with octenidine dihydrochloride. The application of photodynamic therapy has demonstrated to be a good alternative, with an effective antifungal effect against Candida albicans, avoiding the side effects on patients, like those from octenidine dihydrochloride.

Effects of Methylene Blue on Ovarian Torsion-Detorsion Injury in a Rat Model.

Methylene blue (MB) is an antioxidant that ameliorates ischemia-reperfusion injury in several tissues. We analyzed the effects of MB as an inhibitor of torsion-detorsion injury in rat ovaries. Rats were randomly divided into 5 groups. Group 1 was the sham group, in which only laparotomy was performed. Group 2 was the torsion group, with 3hours of ischemia. Group 3 was the torsion+MB group, with 3hours of ischemia after MB administration. Group 4 was the torsion-detorsion group, with 3hours of ischemia and reperfusion. Finally, group 5 was the torsion-detorsion+MB group, with 3hours of ischemia and MB administration before detorsion/reperfusion. Ovary injuries were histopathologically scored. Malondialdehyde (MDA) and total protein levels in ovarian tissues were determined, and long pentraxin-3 (PTX3) levels were measured in ovarian tissue using an enzyme-linked immunosorbent assay. In comparing group 4 with group 5 and group 2 with 3, histopathological parameters reflecting injury were significantly increased in groups 4 and 2. Group 3 generated increased MDA levels when compared with group 2 (P<.05). However, there was no significant difference between groups 2 and 3 in terms of plasma PTX3 levels. MDA and PTX3 levels decreased in group 5 in comparison with group 4 for MDA (P<.000) and PTX3 levels (P<.01). MB alleviated ischemia-reperfusion ovary injury in our experimental model.

Effect of Methylene Blue and PI3K-Akt Pathway Inhibitors on the Neurovascular System after Chronic Cerebral Hypoperfusion in Rats.

Methylene blue (MB) has a protective effect on cognitive decline caused by chronic hypoperfusion, but the specific mechanism is not clear. This article aims to determine whether MB protects vascular neurons through PI3K/Akt and plays a role in improving cognitive impairment. Molecular biological methods, the hippocampal neuronal density test, the hippocampal vascular network density test, and dynamic enhanced magnetic resonance imaging (MRI) were used to detect the blood-brain barrier permeability and Evans blue leakage rate in the hippocampus. We also observed and evaluated the changes in the above results after administration of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway protein inhibitor LY294002. There were significant differences for cerebral blood flow (CBF) between the chronic cerebral hypoperfusion (CCH) + MB group (100ml/100g/min) and the CCH group (60ml/100g/min, P < 0.05). After using LY294002, the CBF of the CCH + MB + LY294002 group dropped to 82ml/100g/min. The vascular density in the CCH + MB group was 23%, which is significantly higher than that in the CCH group (15.1%) (P < 0.05). The vascular density (17.5%) in the CCH + MB + LY294002 group was significantly higher than that in the CCH group but lower than that in the CCH + MB group. Western blotting results showed that one week after intraperitoneal injection of MB, the expression of t-Akt and p-Akt in the CCH + MB group was increased after CCH, and LY294002 partially blocked this up-regulation effect (CCH + MB + LY294002 group). MB is a potential therapy for the relief of mild cognitive impairment associated with CCH, vascular dementia, and Alzheimer's disease.

Use of a radiopaque localizer grid and methylene blue staining as an aid to reduce radiation exposure

Background Localization of small femur lesions for resection can be challenging and may be associated with the need for significant fluoroscopic imaging and tissue dissection. This study was performed to evaluate the use of a radiopaque localizer grid along with methylene blue staining for resection of small femur lesions in children, and to determine the effectiveness of this effectiveness at reducing radiation exposure and tissue injury. Material and methods A radiopaque localizer grid was used to identify the body surface site of bone lesions, and then 0.02–0.03 mL of methylene blue was injected into the bone lesions. After skin incision, the blue bone tissue was found and complete lesion resection performed. Results A radiopaque localizer grid was utilized to plan the point of entry for lesion resection. The average operation time was shorter, and the C-arm was used less frequently, and the incision length was shorter in the grid and methylene blue group compared with the control group. Conclusion A radiopaque localizer grid is a simple and practical device for efficient localization of the skin entry site, and methylene blue accurately pinpoints bone lesions, reducing radiation exposure and tissue injury.

Natural adsorption of methylene blue by waste fallen leaves of Magnoliaceae and its repeated thermal regeneration for reuse

In this study, waste fallen leaves of Magnolia denudate (MDL), Magnolia grandiflora (MGL) and Michelia figo (MFL) were used as adsorbent for removing soluble methylene blue (MB) from aqueous solution. Results showed that the maximum adsorption capacity of MDL, MGL, and MFL were determined to be 185.19 mg/g, 149.25 mg/g, and 238.10 mg/g, which was higher than other reported leaf-based materials. It was found that the adsorption of MB by fallen leaves was a spontaneous and endothermic process, which could be described by Langmuir isotherm (R2 > 0.995) and pseudo-second-order kinetics (R2 > 0.992). Moreover, an environmentally friendly thermal method was applied for regeneration of used adsorbents, by which used MFL was converted to stable MFL-biochar with satisfactory adsorption capacity (139.40 mg/g) for three consecutive cycles. Electrostatic attraction between MB and carboxyl groups was identified as the main mechanism of the observed adsorption. Overall the article provided a novel material as well as regeneration method for potential environmental-sustainable dye wastewater treatment.

The Metabolism of Methylene Blue and Its Derivatives in Japanese Eel (Anguilla Japonica)

Methylene blue (MB) is commonly used in aquaculture as a fungicide and antidotes. This study was designed to explore the pharmacokinetics of MB in Japanese eel ( Anguilla Japonica ) immersed in 10 mg L −1 and 20 mg L −1 MB for 0.5 h. The concentrations of MB and its derivatives in the blood, liver, kidney, skin and muscle were determined by HPLC after immersion. The results showed that the changes of drug concentrations in Japanese eel were basically the same in different dose groups, showing a general trend of increasing at first and then decreasing, but the peak time was slightly different. The peak concentration of the drug was positively correlated with the dose level. The peak concentrations of MB in MB (20 mg L −1 ) group, MB, azure A and azure B in the tissues of Japanese eel were significantly higher than those in MB (10 mg L −1 ) group. Moreover, MB, azure A and azure B remained for a long time and could still be detected at 64 days, and azure C was not detected in tissues.