Privileged structures have been widely used as an effective template for the research and discovery of high value chemicals. Coumarin is a simple scaffold widespread in Nature and it can be found in a considerable number of plants as well as in some fungi and bacteria. In the last years, these natural compounds have been gaining an increasing attention from the scientific community for their wide range of biological activities, mainly due to their ability to interact with diverse enzymes and receptors in living organisms. In addition, coumarin nucleus has proved to be easily synthetized and decorated, giving the possibility of designing new coumarin-based compounds and investigating their potential in the treatment of various diseases. The versatility of coumarin scaffold finds applications not only in medicinal chemistry but also in the agrochemical field as well as in the cosmetic and fragrances industry. This review is intended to be a critical overview on coumarins, comprehensive of natural sources, metabolites, biological evaluations and synthetic approaches.

An overview of coumarin as a versatile and readily accessible scaffold with broad-ranging biological activities

Tissue diagnosis of peripheral pulmonary lesions (PPLs) can be challenging. In the past, flexible bronchoscopy was commonly performed for this purpose but its diagnostic yield is suboptimal. This has led to the development of new bronchoscopic modalities such as radial endobronchial ultrasound (R-EBUS), electromagnetic navigation bronchoscopy (ENB) and virtual bronchoscopy (VB). We performed this meta-analysis using data from previously published R-EBUS studies, to determine its diagnostic yield and other performance characteristics. Ovid MEDLINE and PubMed databases were searched for R-EBUS studies in September 2016. Diagnostic yield was calculated by dividing the number of successful diagnoses by the total number of lesions. Meta-analysis was performed using MedCalc (Version 16.8). Inverse variance weighting was used to aggregate diagnostic yield proportions across studies. Publication bias was assessed using funnel plot and Duval and Tweedie's test. 57 studies with a total of 7872 lesions were included in the meta-analysis. These were published between October 2002 and August 2016. Overall weighted diagnostic yield for R-EBUS was 70.6% (95% CI: 68–73.1%). The diagnostic yield was significantly higher for lesions >2 cm in size, malignant in nature and those associated with a bronchus sign on computerized tomography (CT) scan. Diagnostic yield was also higher when R-EBUS probe was within the lesion as opposed to being adjacent to it. Overall complication rate was 2.8%. This is the largest meta-analysis performed to date, assessing the performance of R-EBUS for diagnosing PPLs. R-EBUS has a high diagnostic yield (70.6%) with a very low complication rate.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/resp.12980

Radial endobronchial ultrasound for the diagnosis of peripheral pulmonary lesions: A systematic review and meta-analysis

Pro-health activity of dandelion (Taraxacum officinale L.) and its food products – history and present

Spinal tuberculosis is the most common form of osteoarticular tuberculosis. Fractures, slippage, and increasing deformity have been reported with the use of autologous rib grafts after anterior spinal decompression. Forty-one patients with neurologic deficits caused by spinal tuberculosis had radical anterior decompression, and the anterior column was reconstructed with fresh-frozen femoral allografts and stabilized with a single-rod screw construct. Antituberculous therapy was administered for 12 months and complete neurologic recovery occurred in 32 patients. The incorporation of allografts commenced between 12 and 18 months. Fusion and remodeling was observed in 33 patients and partial remodeling with fusion was observed in eight patients at a mean followup of 6.4 years. Fortytwo percent correction of the kyphosis was achieved and there were no cases of fracture or late sepsis. Fresh-frozen allografts and anterior instrumentation are superior to rib grafts in supporting the anterior spinal column, and although fusion occurred late, the grafts remained stable.

The outcome of allografts and anterior instrumentation in spinal tuberculosis : Osteoarticular Tuberculosis

Natural deep eutectic solvents (NADES) have been shown to be more effective in extracting plant marker compounds than are organic solvents. In this study, mixtures of choline chloride or betaine with three combinations of sugar molecules (glycerol, xylitol, and sorbitol) and three combinations of organic acids (lactic acid, citric acid, and malic acid) were used as solvents in ultrasonic-assisted extraction (UAE) of trans-cinnamaldehyde and coumarin from cinnamon bark [Cinnamomum burmannii (Nees & T. Nees) Blume]. Optimization of extraction conditions to obtain the optimal trans-cinnamaldehyde content was performed by varying the percentage of water in NADES and extraction time. Efficiency of extraction was determined by conventional extraction performed by maceration, reflux, and the soxhlet method using 96% ethanol for comparison. Trans-cinnamaldehyde and coumarin contents were determined by high-performance liquid chromatography. The surfaces of samples before and after extraction were observed by scanning electron microscopy (SEM). The study results showed that choline chloride–citric acid (1:2) with 40% water addition for 30 minutes produced the highest trans-cinnamaldehyde content of 9.24 ± 0.01 mg/g dry weight. The highest trans-cinnamaldehyde content from conventional extraction using the maceration method was 1.93 ± 0.01 mg/g dry weight. SEM analysis of sample surfaces showed that the ruptured cells in the NADES-UAE method gave a higher trans-cinnamaldehyde yield than that from the shrunken and damaged cells in the conventional extraction. NADESUAE provided higher extraction efficiency for trans-cinnamaldehyde and coumarin from C. burmannii than that of the conventional methods using 96% ethanol as solvent.

/pdf/natural-deep-eutectic-solvents-ultrasound-assisted-40mpp0wm6s.pdf

Natural deep eutectic solvents ultrasound-assisted extraction (NADES-UAE) of trans-cinnamaldehyde and coumarin from cinnamon bark [Cinnamomum burmannii (Nees T. Nees) Blume]

Objective The aim of this study was to investigate the antibiofilm activity of coumarin against Candida albicans. Methods The efficacy of coumarin against biofilm formation and the mature biofilm of C. albicans was quantified by crystal violet (CV) staining and the 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) reduction assay. The effect of coumarin on C. albicans adhesion was assessed on polystyrene plates and by using the cell surface hydrophobicity (CSH) assay. The morphological transition of C. albicans was conducted in two types of hyphae-inducing media at 37 °C. The expression of hypha/biofilm-related genes was evaluated using qRT-PCR analysis. A rescue experiment involving addition of exogenous cyclic adenosine monophosphate (cAMP) was performed to investigate the involvement of cAMP in the yeast-to-hyphae transition. A C. albicans-infected Caenorhabditis elegans model was used to test the anti-virulence efficacy of coumarin. Results Treatment with coumarin strongly affected the capacity of C. albicans to form biofilm and significantly impaired the preformed mature biofilm. The addition of coumarin notably inhibited C. albicans adhesion, CSH, and filamentation. The expression of some adhesion- and hypha-related genes, including HWP1, HYR1, ECE1, and ALS3, was remarkably down-regulated upon exposure to coumarin. Supplementation with cAMP partly rescued the coumarin-induced defects in hyphal development. Finally, coumarin prolonged survival in C. albicans-infected nematodes. Conclusion Coumarin inhibited C. albicans biofilm, which was associated with attenuated adhesion and hyphal growth.

Activity of coumarin against Candida albicans biofilms.

BACKGROUND The aim of this study is to evaluate the correlation of the left ventricular diastolic function and the left ventricular geometry in patients with obstructive sleep apnoea syndrome (OSAS) by echocardiography. METHODS The 181 patients diagnosed with OSAS were divided into the normal geometry group (NG), the concentric remodelling group (CR), the eccentric hypertrophy group (EH) and the concentric hypertrophy group (CH). Pearson correlation analysis and multiple linear regression analysis were performed toward the correlation of the left ventricular diastolic function and the left ventricular geometry. RESULTS The E peak in the EH and CH group was significantly reduced, with significant difference; the E/A, Em, Am and Em/Am was reduced in the order of the CR, EH and CH groups, while E/Em was increased, and the difference was significant. Pearson correlation analysis revealed that the Em/Am showed significant negative correlations with the left ventricular mass index (LVMI) [r = -0.419] and relative wall thickness (RWT) [r = -0.289], while the E/Em was significantly positively correlated with the LVMI (r = 0.638) and RWT [r = 0.328] (p < 0.001). Multiple linear regression analysis revealed that LVMI and RWT had influence on the Em/Am and E/Em (r2 = 0.402, r2 = 0.107, p < 0.001). The left ventricular diastolic dysfunction was the worst in the CH group. CONCLUSIONS There was correlation between the left ventricular diastolic dysfunction and the changes in cardiac geometry.

Correlation of Left Ventricular Diastolic Function and Left Ventricular Geometry in Patients with Obstructive Sleep Apnoea Syndrome.

The aim of this study was to discuss the value and significance of quality control circle (QCC) in the reduction of the surgical site infection (SSI). From January 2012 to December 2013, a total of 32 patients with surgical site infection were included in the study. Quality control circle was established to control the SSI in these patients. The tangible and intangible results of QCC were compared and analysed. On the tangible results, achievement and improvement index on internal error reduction, SSI rate reduction, patients satisfaction, working quality improvement was 97.84% ± 16.47%, 95.04% ± 50.33%, 90.58% ± 22.83%, 100.6% ± 22.8% and 31.12% ± 13.2%, 34.41% ± 22.96%, 40.22% ± 25.39%, 49.2% ± 25.4%. On the intangible results, one to two points improvement was found in 83% of the QCC members, and 12% of the QCC members have > 2 points improvement. Quality control circle could reduce the SSI rates, especially on the intangible and tangible results. Quality control circle could be employed as effective tool to improve the medical quality.

/pdf/a-study-of-quality-control-circle-on-the-reduction-of-the-5aaksxswmk.pdf

A Study of Quality Control Circle on the Reduction of the surgical Site Infection.

Objective: To evaluate the efficacy of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of thoracic sarcoidosis. Methods: A retrospective dataset of 35 patients who received EBUS-TBNA was analyse d. These patients underwent EBUS-TBNA due to suspected sarcoidosis (radiographic stages I and II) with enlarged hilar or mediastinal lymph nodes (≥ 1.0 cm) revealed by computed tomography. When EBUS-TBNA was considered to be nondiagnostic, surgical biopsy and clinical and radiological follow-up was performed. Results: Twenty-eight of 35 (80%) patients had a final diagnosis of sarcoidosis. Among them, 25 (89.3%) were diagnosed by EBUS-TBNA. Conclusion: Endobronchial ultrasound-guided transbronchial needle aspiration is a safe and effective procedure for the diagnosis of stages I and II of thoracic sarcoidosis.

/pdf/efficacy-of-endobronchial-ultrasound-guided-transbronchial-2k24m0e4j4.pdf

Efficacy of Endobronchial Ultrasound-guided Transbronchial Needle Aspiration in the Diagnosis of Thoracic Sarcoidosis.

A 32-year old male patient was wounded by a pistol. As shown in computed tomography (CT) scanning images, there was comminuted fracture of the left mandible and the bullet was found in the left side behind the sixth cervical vertebra. After the patient was hospitalized, the debridement was done in the emergency room and the operation of open reduction and internal fixation for comminuted fracture of left mandible was performed successfully. Eighteen days later, the patient was taken to surgery for anterior cervical decompression and fusion with autogenous iliac bone grafting for the sixth cervical vertebra. Postoperative follow-up of the patient over two years indicated that the left biceps muscle strength was recovered to level 4. Gunshot wound to the face associated with injury of the low cervical spine has the possibility of survival. It is safe to treat facial wounds early in the patient's treatment course, even if the bullet remains in the cervical vertebral body and there is neurological function damage.

/pdf/gunshot-caused-facial-injury-combined-with-lower-cervical-4ri8j66i78.pdf

Gunshot-caused Facial Injury Combined with Lower Cervical Spine Injury: A Case Report

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