24 research outputs found
Curcumenol from Curcuma zedoaria: a second monoclinic modification
The title compound, systematic name 9-isopropylidene-2,6-dimethyl-11-oxatricyclo[6.2.1.01,5]undec-6-en-8-ol, C15H22O2, which crystallizes with two molecules of similar conformation in the asymmetric unit, features three fused rings, two of which are five-membered and the third six-membered. Of the two five-membered rings, the one with an O atom has a distinct envelope shape (with the O atom representing the flap). The six-membered ring is also envelope-shaped as it shares a common O atom with the five-membered ring. In the crystal, the two independent molecules are linked by a pair of O—H⋯O hydrogen bonds, generating a dimer
A Preliminary Qualitative Study of Two Common Acacia Species in Sudan
This research is dealing with the analysis of tannins of two common Acacia species of Sudan i.e. Acacia nilotica and Acacia seyal. Bark samples from collections of the two acacia species were extracted with distilled water, 80% methanol and 70% acetone. Two sets of extraction were made, one by boiling, and the other by shaking the samples in the respective solvent for eight hours at room temperature. It was found that the 70% acetone was a more efficient solvent than either water or 80% methanol. In addition, qualitative analysis of the phytochemicals showed that the fruits (garad) contain tannins materials, flavonoids and coumarins
Heat transfer and fluid flow over microscale backward and forward facing step: A review
Research on convective heat transfer in the microscale backward-facing step (MBFS) and microscale forward-facing step (MFFS) has been extensively conducted in the past decade. This review summarizes numerous researches on the three topics; the first section focuses on studying the effect of the geometry on the fluid flow and heat transfer behavior. The second and the third sections concentrate on the effect of the inclination angle and the flow regime on the fluid flow and heat transfer enhancement. The purpose of this article is to get a clear view and detailed summary of the influence of several parameters such as the geometrical specifications, type of fluids and boundary conditions. The enhancement in the Nusselt number is the main target of such research where correlation equations were developed in numerical and experimental studies are reported
The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy
Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations.
Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves.
Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p 90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score.
Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey
Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020
Experimental and numerical study of nanofluid flow and heat transfer over microscale backward-facing step
Experimental and numerical studies were presented to reveal the flow and heat transfer characteristics of nanofluid laminar flow over the microscale backward-facing step (MBFS). The duct inlet and the step height were 400 μm and 600 μm respectively. All the walls considered adiabatic except the downstream wall is heated by uniform heat flux. The experiment is conducted at the Reynolds number range from 280 to 470. The distilled water is considered as a base fluid with two types of nanoparticles SiO2 and Al2O3 immersed in the base fluid. The particle diameter is 30 nm and the range of nanoparticles volume fraction in the base fluid varied from 0 to 0.01. The measurement results revealed that the water-SiO2 nanofluid has the highest Nusselt number. It is found also that the Nusselt number increase with increases volume fraction. The water-SiO2 nanofluid with higher volume fraction has the highest Nusselt number. The friction factor of water-Al2O3 was higher than of water-SiO2 mixture. The numerical results were in good agreement with the measurement results
A Preliminary Qualitative Study of Two Common Acacia Species in Sudan
This research is dealing with the analysis of tannins of two common Acacia species of Sudan i.e. Acacia nilotica and Acacia seyal. Bark samples from collections of the two acacia species were extracted with distilled water, 80% methanol and 70% acetone. Two sets of extraction were made, one by boiling, and the other by shaking the samples in the respective solvent for eight hours at room temperature. It was found that the 70% acetone was a more efficient solvent than either water or 80% methanol. In addition, qualitative analysis of the phytochemicals showed that the fruits (garad) contain tannins materials, flavonoids and coumarins
Bio-guided isolation and bioinformatic studies of cytotoxic phytosterols from Acanthospermum hispidum DC against breast (MCF7) and colorectal (HT29) cancer cells
Acanthospermum hispidum DC (Asteraceae), a traditional medicinal plant, plays a role as an alternative remedy for various diseases, such as bacterial and viral infections, jaundice, malaria, fever, gastrointestinal disorders, headache, convulsions, and snake bites. Flavonoids, alkaloids, saponins, tannins, terpenes, steroids, and cardioactive glycosides are the distinct classes of metabolites in the plant. Although A. hispidum was suggested as a promising antitumor phytomedicine, no studies identified its potential cytotoxic components. In this study, the cytotoxic compounds of A. hispidum were isolated using chromatographic techniques guided by in vitro MTT cytotoxicity assay against selected cancer cell lines; breast cancer (MCF7), colorectal adenocarcinoma (HT29), and hepatoblastoma (HepG2). The selective index (SI) was assessed on MRC5 (Normal human fetal lung fibroblast) cell line. The dichloromethane fraction (DCM) showed remarkable cytotoxic activity against MCF7 and HT29 (%Cell viability; 46.15 and 60.5, respectively). Hence, the main bioactive fraction from DCM was purified to afford two phytosterols; stigmasterol (1) and β-sitosterol (2), which were identified by 1-D and 2-D NMR spectroscopy. Cytotoxic evaluation of 1 and 2 revealed that β-sitosterol showed better selective cytotoxicity against MCF7 and HT29 (IC50 4.07 μg/mL, SI 2.63; IC50 4.52 μg/mL, SI 2.37) compared to stigmasterol (IC50 5.43 μg/mL, SI 1.38; IC50 4.21 μg/mL, SI 1.78), respectively. Bioinformatic assessments of drug-likeness and ADMET properties demonstrated that most criteria were obeyed by the investigated compounds except for their poor solubility, which recommended the preparation of special dosage forms, such as nanoformulation to enhance their oral bioavailability. Swiss Target prediction indicated that nuclear receptors represent the main target class (40%). Whereas caspase-3 stimulant activity (a key enzyme in apoptosis) was predicted by the PASS prediction tool as a potential anticancer mechanism. Our study suggests A. hispidum as a potential source of bioactive phytosterols and as a chemopreventive medicinal plant