Biodiesel production from candlenut oil using a non-catalytic supercritical methanol transesterification process: optimization,kinetics, and thermodynamic studies

The present study was conducted to determine the feasibility of biodiesel production from candlenut oil using supercritical methanol (scMeOH) as a non-catalytic transesterification process. The influence of the scMeOH transesterification process was determined with varying pressure (85–145 bar), temperature (260–300 °C), methanol to oil (M : O) ratio (15 : 1–35 : 1), and reaction time (15–25 min). The experimental conditions of the scMeOH transesterification process were designed using central composite design (CCD) of experiments, and the process was optimized using response surface methodology (RSM). It was found that scMeOH temperature, pressure, M : O ratio, and reaction time substantially influenced the transesterification process. The maximum biodiesel yield of 96.35% was obtained at an optimized scMeOH transesterification process at the pressure of 115 bar, the temperature of 285 °C, M : O ratio of 30 : 1, and reaction time of 22 min. A second-order kinetics model and Eyring equations were utilized to determine the kinetics and thermodynamics of biodiesel production from candlenut oil. The activation energy value was determined to be 28.35 KJ mol⁻¹. Analyses of the thermodynamic properties of biodiesel revealed that the transesterification process was non-spontaneous and endothermic. The physicochemical properties of produced candlenut biodiesel via scMeOH complied with most of the biodiesel properties as per ASTM D6751 and EN14214, thereby referring to good quality biodiesel production. The findings of the present study reveal that the scMeOH is an effective non-catalytic transesterification process for biodiesel production from candlenut oil.

The present study was conducted to determine the feasibility of biodiesel production from candlenut oil using supercritical methanol (scMeOH) as a non-catalytic transesterification process.     

Serum IL-18 levels in tuberculosis: comparison with pneumonia, lung cancer and healthy controls

OBJECTIVE: The aim of the present study was to document the serum IL-18 levels in patients with pulmonary tuberculosis (P-TB), extrapulmonary tuberculosis (EP-TB), pneumonia, lung cancer and in healthy controls, and to investigate whether it may assist in the differential diagnosis of P-TB. METHODOLOGY: A total of 116 patients were included in the study. The study population consisted of patients with P-TB, EP-TB, pneumonia and lung cancer and controls. P-TB patients were graded according to sputum positivity and extent of disease. Serum levels of IL-18 (ELISA) were compared between groups and with other clinical measures of disease. RESULTS: Compared with the controls, all groups of patients had increased serum levels of IL-18. The highest mean concentration of IL-18 was observed in P-TB. Serum levels of IL-18 in the patients with P-TB correlated well with the extent of disease. CONCLUSIONS: Although increased serum levels of IL-18 were not specific for TB, the increased levels may favour active TB in radiologically advanced disease where CXR findings are difficult to interpret, and sputum smears or cultures are not helpful.     

Estimation of COVID-19 vaccine effectiveness against hospitalisation in individuals aged ≥ 65 years using electronic health registries; a pilot study in four EU/EEA countries,October 2021 to March 2022

By employing a common protocol and data from electronic health registries in Denmark, Navarre (Spain), Norway and Portugal, we estimated vaccine effectiveness (VE) against hospitalisation due to COVID-19 in individuals aged ≥ 65 years old, without previous documented infection, between October 2021 and March 2022. VE was higher in 65–79-year-olds compared with ≥ 80-year-olds and in those who received a booster compared with those who were primary vaccinated. VE remained high (ca 80%) between ≥ 12 and < 24 weeks after the first booster administration, and after Omicron became dominant.     

A novel homozygous SLC25A1 mutation with impaired mitochondrial complex V: Possible phenotypic expansion

SLC25A1 mutations are associated with combined D,L‐2‐hydroxyglutaric aciduria (DL‐ 2HGA; OMIM #615182), characterized by muscular hypotonia, severe neurodevelopmental dysfunction and intractable seizures. SLC25A1 encodes the mitochondrial citrate carrier (CIC), which mediates efflux of the mitochondrial tricarboxylic acid (TCA) cycle intermediates citrate and isocitrate in exchange for cytosolic malate. Only a single family with an SLC25A1 mutation has been described in which mitochondrial respiratory chain dysfunction was documented, specifically in complex IV. Five infants of two consanguineous Bedouin families of the same tribe presented with small head circumference and neonatal‐onset encephalopathy with severe muscular weakness, intractable seizures, respiratory distress, and lack of psychomotor development culminating in early death. Ventricular septal defects (VSD) were demonstrated in three patients. Blood and CSF lactate were elevated with normal levels of plasma amino acids and free carnitine and increased 2‐OH‐glutaric acid urinary exertion. EEG was compatible with white matter disorder. Brain MRI revealed ventriculomegaly, thin corpus callosum with increased lactate peak on spectroscopy. Mitochondrial complex V deficiency was demonstrated in skeletal muscle biopsy of one infant. Homozygosity mapping and sequencing ruled out homozygosity of affected individuals in all known complex V‐associated genes. Whole exome sequencing identified a novel homozygous SLC25A1 c.713A>G (p.Asn238Ser) mutation, segregating as expected in the affected kindred and not found in 220 control alleles. Thus, SLC25A1 mutations might be associated with mitochondrial complex V deficiency and should be considered in the differential diagnosis of mitochondrial respiratory chain defects.

     

Effects of school-based cardiovascular-fitness training in children with mental retardation

The aim of this study was to investigate the effects of a school-based cardiovascular-fitness-training program in children with mental retardation (MR). Thirty boys (8-15 years old) with mild to moderate mental retardation were randomly divided into 2 groups--experimental (EX) and control (CN). The EX group underwent 10 weeks of training 3 times/week for a duration of 1 hr/session at 60-80% peak heart rate. At Week 10, significant increases in 20-m shuttle-run-test (20-MST) laps were observed for the EX group. No improvements were found in percent body fat. No changes were observed for the CN. The school-based training program might prove useful in improving the cardiovascular fitness of children with MR.     

Utility of Pit-1 Immunostaining in Distinguishing Pituitary Adenomas of Primitive Differentiation from Null Cell Adenomas

Pit-1 immunostaining is not routinely used in the characterization of pituitary adenomas, and its utility in distinguishing adenomas dedicated towards the lactotroph, somatotroph, and thyrotroph lineage from null cell adenomas warrants further evaluation. Pituitary adenomas that were negative for expression of a basic panel of hormonal markers (ACTH, prolactin, and growth hormone) were further evaluated for TSH, SF-1, and Pit-1 expression using a tissue microarray. Among the 147 identified pituitary adenomas that were negative for ACTH, prolactin, growth hormone, and TSH, expression of SF-1 was present in 68 cases (46%). Of the remaining 72 cases with sufficient tissue for further analysis, four were Pit-1 positive (6% of the adenomas negative for ACTH, prolactin, growth hormone, TSH, and SF-1); the remaining 68 were potentially null cell adenomas. Two of the Pit-1-positive adenomas displayed a paranuclear CAM 5.2 staining pattern suggestive of a sparsely granulated somatotroph adenoma; however, only one case contained fibrous bodies within a majority of the adenoma cells. Our data suggests that Pit-1 can be utilized as a second tier immunostain in cases of clinically non-functioning adenomas that are immunonegative for ACTH, prolactin, growth hormone, TSH, and SF-1 in order to further segregate rare cases of Pit-1-positive adenomas from null cell adenomas. Pit-1 immunostaining can recognize rare cases of sparsely granulated somatotroph adenomas that appear immunonegative for growth hormone, as well as rare cases of other Pit-1-positive adenomas that are negative for Pit-1 lineage hormones. Overall, pituitary adenomas of the Pit-1 lineage that do not produce prolactin, growth hormone, or TSH are rare, with only four cases identified in the current study.     

Impact of p53 and Ki-67 in predicting recurrence and progression of superficial (pTa and pT1) urothelial cell carcinomas of urinary bladder

In predicting the aggressive behavior of bladder tumors, the histopathological characteristics of grade and invasive stage are of principal importance. However, for predicting tumor recurrence and progression, these are sufficient only to a limited extent, particularly in the case of superficial (pTa and pT1) urothelial cell carcinomas. New prognostic factors are therefore needed to avoid either insufficient or excessive treatment. In this retrospective study, we investigated the prognostic value of the p53 and Ki-67 immunoreactivity indices. The present study included 118 superficial urinary bladder tumors consisting of 58 recurrent and 60 non-recurrent cases. Twenty of the recurrent tumors progressed into a higher grade and/or invasive stage. Paraffin immunohistochemical analysis was carried out using anti-p53 and anti-Ki-67 antibodies on the initial tumor tissues. We concluded that there is a highly significant relationship between the p53 and Ki-67 immunoreactivities and the histological grade and pathological stage of the tumors (P < 0.0001). We observed a significant relationship between the presence of recurrence and progression and the p53 immunoreactivity index (P < 0.01 and P = 0.017, respectively) and Ki-67 immunoreactivity index (P < 0.0001 and P = 0.046, respectively). Positivity for p53 and Ki-67 can demonstrate the risk of recurrence (p53: sensitivity = 76%, specificity = 58%; Ki-67: sensitivity = 86%, specificity = 48%) and progression (p53: sensitivity = 80%, specificity = 46%; Ki-67: sensitivity = 85%, specificity = 36%; ). We believe that both of these immunohistochemical markers can be considered valuable in addition to classical histopathological prognostic parameters for predicting recurrence and progression risks.