Injectable citrate-based mussel-inspired tissue bioadhesives with high wet strength for sutureless wound closure

The existing surgical adhesives are not ideal for wet tissue adhesion required in many surgeries such as those for internal organs. Developing surgical adhesives with strong wet tissue adhesion, controlled degradability and mechanical properties, and excellent biocompatibility has been a significant challenge. Herein, learning from nature, we report a one-step synthesis of a family of injectable citrate-based mussel-inspired bioadhesives (iCMBAs) for surgical use. Within the formulations investigated, iCMBAs showed 2.5-8.0 folds stronger wet tissue adhesion strength over the clinically used fibrin glue, demonstrated controlled degradability and tissue-like elastomeric mechanical properties, and exhibited excellent cyto/tissue-compatibility both in?vitro and in?vivo. iCMBAs were able to stop bleeding instantly and suturelessly, and close wounds (2?cm long?×?0.5?cm deep) created on the back of Sprague-Dawley rats, which is impossible when using existing gold standard, fibrin glue, due to its weak wet tissue adhesion strength. Equally important, the new bioadhesives facilitate wound healing, and are completely degraded and absorbed without eliciting significant inflammatory response. Our results support that iCMBA technology is highly translational and could have broad impact on surgeries where surgical tissue adhesives, sealants, and hemostatic agents are used.     

Simultaneous determination of levodopa and carbidopa in levodopa-carbidopa tablets by ATR-FTIR spectrometry

A novel analytical procedure has been developed for quantitative determination of levodopa and carbidopa in aqueous binary solutions acidified by HCl and without any other sample pretreatment. The method is based partially on least squares treatment of data obtained by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrometry in 1211-1315 cm(-1) and 1488-1550 cm(-1) spectral regions. The simple, rapid, and accurate proposed method was applied to determine levodopa and carbidopa in Levodopa-C tablets. The statistical parameters, such as R2, RSD, SEE, SECV, LOD, and recovery were evaluated. Number of factors, scans, and resolution were optimized. In this method R2 and RSD for levodopa and carbidopa were (0.9965, 1.209) and (0.9537, 0.813), respectively.     

Novel external sensor array for capsule endoscopy

Capsule endoscopy (CE) requires placement of an eight-lead sensor array over the abdomen that receives image and localization data transmitted from the capsule. The current process of applying this array to the skin has several disadvantages: firstly, it is time-consuming; secondly, it can be cumbersome for the patient; and thirdly, it is often difficult to place the leads consistently. A new external sensor array system designed to improve this process was tested. It was hypothesized that the new method would be able to receive the transmitted data adequately during CE. The new method and device were tested on an in-patient who had two sets of sensor arrays, batteries, and data recorders placed on her simultaneously. One set was placed in the standard fashion, which served as the control, while the other set was placed using the novel external method. The data provided by the two recorders were compared and the patient's preferences were noted. The quality of the CE images provided by the two methods was identical, but the CE localization tracings were different, presumably due to movement of the gown and leads during the recording period. No signal interference was noted. The patient preferred the external device. A prepositioned external sensor array is capable of transmitting CE data without any loss in image quality, but the localization tracing differs due to movement of the external array. This new method will require testing with a larger sample size in an outpatient setting to allow full assessment of the clinical value of the new approach.     

Treatment of small-bowel diaphragm disease by using double-balloon enteroscopy

BACKGROUND: Double-balloon enteroscopy is a new technique that allows endoscopic therapy throughout the entire length of the small bowel. Diaphragm disease, characterized by thin septa that narrow the small-bowel lumen, is traditionally treated surgically by segmental resection. OBJECTIVE: To report successful endoscopic treatment of diaphragm disease by double-balloon enteroscopy. PATIENTS: Three patients. DESIGN: Case report. INTERVENTIONS: Double-balloon enteroscopy and stricture balloon dilation. RESULTS: We report, for the first time, 3 cases in which diaphragm strictures were successfully treated during double-balloon enteroscopy. In 2 cases, a retained capsule endoscope was removed by the retrograde approach after stricture dilation. LIMITATIONS: Small number of patients and brief length of patient follow up. CONCLUSION: Double-balloon enteroscopy may be used to treat patients with diaphragm disease, thus avoiding potentially complicated surgery.     

Effects of adenosine A2a receptor agonist and antagonist on hippocampal nuclear factor-kB expression preceded by MDMA toxicity

There is an abundance of evidence showing that repeated use of 3,4-methlylenedioxymethamphetamine (MDMA; ecstasy) is associated with brain dysfunction, memory disturbance, locomotor hyperactivity, and hyperthermia. MDMA is toxic to both the serotonergic neurons and dopaminergic system. Adenosine is an endogenous purine nucleoside with a neuromodulatory function in the central nervous system. Nuclear factor kappa-B (NF-kB) plays a pivotal role in the initiation and perpetuation of an immune response by triggering the expression of major inflammatory mediators such as cytokines, chemokines, and adhesion molecules. Here, we investigated the effects of the A2a adenosine receptor (A2a-R) agonist (CGS) and antagonist (SCH) on NF-kB expression after MDMA administration. Male Sprague–Dawley rats were injected to MDMA (10 mg/kg) followed by intraperitoneal injection of either CGS or SCH (0.03 mg/kg each) to animals. The hippocampi were then removed for western blot and RT- PCR analyses. MDMA significantly elevated NF-kB expression. Our results show that administration of CGS following MDMA significantly elevated the NF-kB expression both at mRNA and protein levels. By contrast, administration of the A2a-R antagonist SCH resulted in a decrease in the NF-kB levels. Taken together, these results indicate that, co-administration of A2a agonist (CGS) can protect against MDMA neurotoxic effects by increasing NF-kB expression levels; suggesting a potential application for protection against the neurotoxic effects observed in MDMA users.     

99 mTc-MIBI washout as a complementary factor in the evaluation of idiopathic dilated cardiomyopathy (IDCM) using myocardial perfusion imaging

Rapid technetium-99 m methoxyisobutylisonitrile (99 mTc-MIBI) washout has been shown to occur in impaired myocardia. This study is based on the hypothesis that scintigraphy can be applied to calculate the myocardial 99 mTc-MIBI washout rate (WR) to diagnose and evaluate heart failure severity and other left ventricular functional parameters specifically in idiopathic dilated cardiomyopathy (IDCM) patients. Patients with IDCMP (n = 17; 52.65 ± 11.47 years) and normal subjects (n = 6; 49.67 ± 10.15 years) were intravenously administered 99 mTc-hexakis-2-methoxyisobutylisonitrile (99 mTc-MIBI). Next, early and delayed planar data were acquired (at 3.5-h intervals), and electrocardiogram (ECG)-gated myocardial perfusion single photon emission computed tomography (SPECT) was performed. The 99 mTc-MIBI WR was calculated using early and delayed planar images. Left ventricular functional parameters were also analyzed using quantitative gated SPECT (QGS) data. In target group, myocardial WRs (29.13 ± 6.68%) were significantly higher than those of control subjects (14.17 ± 3.31%; P < 0.001). The 99 mTc-MIBI WR increased with the increasing severity of the NYHA functional class (23.16 ± 1.72% for class I, 30.25 ± 0.95% for class II, 32.60 ± 6.73% for class III, and 37.50 ± 7.77% for class IV; P = 0.02). The WR was positively correlated with the end-diastolic volume (EDV) index (r (2) = 0.216; β = 0.464; P = 0.02 [ml/m(2)], the end-systolic volume (ESV) index (r (2) = 0.234; β = 0.484; P = 0.01 [ml/m(2)]), the summed motion score (SMS) (r (2) = 0.544; β = 0.738; P = 0.00), and the summed thickening score (STS) (r (2) = 0.656; β = 0.810; P = 0.00); it was negatively correlated with the left ventricular ejection fraction (LVEF) (r (2) = 0.679; β = -0.824; P = 0.00). It can be concluded that 99 mTc-MIBI scintigraphy might be a valuable molecular imaging tool for the diagnosis and evaluation of myocardial damage or dysfunction severity.