Selective synthesis of alpha monoglycerides by a clean method: Techno-economic and environmental assessment

This work proposes an alternative green and selective biocatalytic route for Glycerin Monostearate (α-monostearin) production. The conventional method of production uses an elevated temperature. Apart from the high energy consumption, such high temperatures darken the final product's color, lead to random reactions, and produce high orders of diglycerides and triglycerides instead of monoglycerides. The proposed production process was performed by esterifying stearic acid with glycerin in an organic medium using Candida antarctica lipase (Novozym 435) at a mild temperature. The reaction conditions were optimized using the response surface methodology (RSM): optimum conditions were a temperature of 60 °C, glycerin to stearic acid molar ratio of 8:1, and Novozym 435 amount of 6% w/w. The solvent addition remarkably improved the α-monostearin yield to nearly 80% without the need for the energy-intensive distillation step. The conventional autocatalytic esterification (AUT) process was also performed to investigate the comparative monoglyceride yield, and it was found to be 22.5%. Proton nuclear magnetic resonance and gas-chromatography confirmed that α-monostearin could be produced with the highest purity using the proposed enzymatic method (ENZ). Economic and environmental analyses were also conducted for the proposed ENZ process, and the results were compared with those of the AUT process. The total capital investment of α-monostearin production, considering a projected capacity of 4950 t year^?1 and 11% interest for the proposed ENZ process, was favorably 2.5 times lower than that of the AUT process, suggesting a promising investment opportunity. However, the total production costs showed unfavorable negative net present value (NPV) and return on investment (ROI) for the ENZ process and favorable positive NPV and ROI for the AUT process, indicating that the proposed venture is not profitable for α-monostearin production. However, the process can be profitable at improved operational stability of Novozym 435 up to 1 kg per 3-ton product. The carbon footprint was calculated on the basis of the given capacity and conditions of 50 and 656 t CO₂ eq./year for the ENZ and AUT processes, respectively. The synthesis of α-monostearin using the proposed route can be considered a building block toward a cleaner large-scale production of α-monoglycerides.     

Synthesis,Molecular Docking and Biological Evaluation of Diaryl Pyrimidine Derivatives as Urease Inhibitors

Pharmaceutical Chemistry Journal - Urease is a dinickel enzyme that is responsible for the hydrolysis of urea to ammonia and carbon dioxide. A series of bacteria like Helicobacter pylori produce...     

Severity of erectile dysfunction could predict left ventricular diastolic dysfunction in patients without overt cardiac complaint

IntroductionIt has been repeatedly demonstrated that presence of erectile dysfunction (ED) may predate the occurrence of overt event of coronary artery disease. However, the association between severity of ED and left ventricular diastolic dysfunction (LVDD) was rarely reported.AimThe aim of this study was to assess the association between severity of ED and LVDD in patients without overt cardiac complaint.Main Outcome MeasuresThe International Index of Erectile Function (IIEF) was used to assess erectile function. Diastolic Doppler parameters measurements and tissue Doppler imaging were used to assess left ventricular diastolic function.MethodsA total of 230 male ED patients without overt cardiac complaint were enrolled in this study. Erectile function was assessed using the IIEF. Patients were also screened for socio demographic data and medical comorbidities that included age, smoking, diabetes, hypertension, and dyslipidemia. All patients were referred to cardiologist for cardiac assessment. Left ventricular diastolic function that included diastolic Doppler parameters measurements and tissue Doppler imaging were also assessed.ResultsMean age ± standard deviation was 57.5 ± 5.6 (range of 42–81). There were significant associations between the following risk factors: age, obesity, smoking, hypertension, dyslipidemia, and increased severity of ED (P < 0.05 for each). Of the patients, 77.4%, 74.8%, 80%, and 66.1% had abnormal transmitral E/A (E/A) ratio, deceleration time (DT), isovolumic relaxation time (IVRT), mitral E velocity/tissue Doppler imaging E velocity (E/Em) ratio, respectively. Only the means of IVRT and (E/Em) ratio had significant associations with increased severity of ED (P < 0.001 for each). There were significant associations between increased severity of ED and the following categorical echo parameters: grades 1 and 2 of E/A ratio, DT, IVRT, and grades 1, 2, and 3 of (E/Em) ratio (P < 0.05 for each).Conclusions. The current study clearly demonstrated that LVDD is prevalent among patients with ED‐associated medical comorbidities without overt cardiac complaint. There were significant associations between increased severity of ED and presence of LVDD in those patients. El‐Sakka AI, Morsy AM, and Fagih BI. Severity of erectile dysfunction could predict left ventricular diastolic dysfunction in patients without overt cardiac complaint. J Sex Med 2011;8:2590–2597.     

Outcome of 234 pregnancies in 140 renal transplant recipients from five middle eastern countries

OBJECTIVE: To study the pregnancy and offspring outcomes in postrenal transplant recipients. METHODS: This is a retrospective case-note review study investigating the outcome of 234 pregnancies in 140 renal transplant recipients from five different Middle Eastern countries. RESULTS: Of the overall pregnancies 74.4% were successful albeit with high prevalences of preterm and Caesarean deliveries (40.8% and 53%, respectively). The mean serum creatinine did not rise significantly during pregnancy in the group as a whole but did so in patients who had serum creatinine of or above 150 micromol/L at the beginning of their pregnancies. The mean birth weight was (2,458 g) with 41.3% of the newborns being of low birth weight (<2,500 g). The prevalences of stillbirths were 7.3% and of spontaneous abortion was 19.3%. Preeclampsia and gestational diabetes were observed in 26.1% and 2% of pregnancies, respectively. CONCLUSIONS: In the presence of good allograft function, the majority of pregnancies in renal transplant recipients have a good outcome but with increased incidence of preeclampsia, reduced gestational age, and low birth weights. Patients with baseline serum creatinine of above 150 micromol/L have an increased risk of allograft dysfunction resulting from the pregnancy.     

Quality of life outcomes in revision vs primary total hip arthroplasty: a prospective cohort study

This study included 143 patients who had revision total hip arthroplasty (THA) and 144 patients who had primary THA. The primary outcome variable in this study was the Western Ontario and McMaster Universities Osteoarthritis Index scores. Univariate and multivariate regression models were used to assess the relationship between surgical procedure and postoperative health related quality of life outcomes. The mean follow-up period was 1.7 years (range, 1-3 years). The mean preoperative function of patients with primary THA was significantly worse than that in the revision group (delta = -6.2; P = .013). Postoperative functional outcome was significantly better in patients with primary THA (delta = 6.5, P = .016) than in patients who had revision THA. The magnitude of improvement in quality of life is greater for the patient with primary THA in comparison to the patient with revision THA.     

A comparison between patient recall and concurrent measurement of preoperative quality of life outcome in total hip arthroplasty

The objective is to evaluate the reliability of patients' recall of preoperative pain and function during the immediate postoperation period after total hip arthroplasty. A prospective cohort of 104 patients completed a survey about their quality of life before operation, and recalled preoperative status at 3 days, 6 weeks, and 12 weeks after operation. Quality of life was measured by the Western Ontario and McMaster University Osteoarthritis Index, the Oxford-12 hip score, and the 12-item Short-Form score. The intraclass correlation coefficient and Spearman correlation coefficient were used to compare preoperative quality of life scores to the scores recalled. The reliability of recall remained high up to 3 months postoperation. Patients are able to accurately recall their preoperative function for up to 3 months after total hip arthroplasty.     

Cerebral venous sinus thrombosis in a neonate with homozygous prothrombin G20210A genotype.

We describe a 7-day-old infant who presented with extensive cerebral venous sinus thrombosis (CVST) and was found to be homozygous for the prothrombin G20210A gene mutation. No other known risk factors for thrombosis were identified.