Dermal exposure to kerosene

Young healthy albino male mice were subjected to repeated exposure to kerosene by wrapping each of their hind feet with a muslin cloth (1 x 10 cm) wetted with kerosene (0.1 ml). Exposure varied from 15 to 60 min/day for 7 consecutive days. Repeated exposure to kerosene produced histologic changes in the foot pad skin and popliteal lymph nodes of mice and systemic toxic manifestations such as variation in hematologic profile, significant decreases in relative weight of thymus, spleen and abdominal lymph nodes and altered histology. Three weeks of non-exposure rest indicated the reversible nature of kerosene-induced toxicity. Furthermore, observations made in 24 human subjects chronically exposed to kerosene in an automobile workshop revealed high incidence of oil acne and dermatitis of varying degrees. The study demonstrates a need for caution where ever prolonged dermal exposure to kerosene in occupational situations obtains.     

Choline and ethanolamine phosphorylation in rodents as a function of age

The activities of choline kinase and ethanolamine kinase in rat and mouse liver and mouse kidney were evaluated at different stages of postnatal development. The activities were calculated as units per g tissue, units per mg protein and as units in the organ mass corresponding to 100 g body weight. Developmental variations were observed in the enzyme activities and in the ratio of ethanolamine kinase to choline kinase activity with age of animal. The weaning of animals was not accompanied by any marked and consistent changes in the kinase activities by all parameters in the liver of rat and mouse or kidney of mouse. The results obtained also support the possible distinction between the proteins catalyzing the phosphorylation of choline and ethanolamine.     

Alphabet strategy for diabetes care: A checklist approach in the time of COVID-19 and beyond

Chronic disease management requires achievement of critical individualised targets to mitigate again long-term morbidity and premature mortality associated with diabetes mellitus. The responsibility for this lies with both the patient and health care professionals. Care plans have been introduced in many healthcare settings to provide a patient-centred approach that is both evidence-based to deliver positive clinical outcomes and allow individualised care. The Alphabet strategy (AS) for diabetes is based around such a care plan and has been evidenced to deliver high clinical standards in both well-resourced and under-resourced settings. Additional patient educational resources include special care plans for those people with diabetes undertaking fasting during Ramadan, Preconception Care, Prevention and Remission of Diabetes. The Strategy and Care Plan has facilitated evidence-based, cost-efficient multifactorial intervention with an improvement in the National Diabetes Audit targets for blood pressure, cholesterol levels and glycated haemoglobin. Many of these attainments were of the standard seen in intensively treated cohorts of key randomized controlled trials in diabetes care such as the Steno-2 and United Kingdom Prospective Diabetes Study. This is despite working in a relatively under-resourced service within the United Kingdom National Health Service. The AS for diabetes care is a useful tool to consider for planning care, education of people with diabetes and healthcare professional. During the time of the coronavirus disease 2019 pandemic the risk factors for the increased mortality observed have to be addressed aggressively. The AS has the potential to help with this aspiration.     

Fluoxetine pretreatment effects pharmacokinetics of 3,4-methylenedioxymethamphetamine (MDMA, ECSTASY) in rat

Fluoxetine has been shown to provide protection from MDMA induced long term neurotoxicity. The purpose of this investigation is to evaluate the pharmacokinetic drug interaction between MDMA and fluoxetine and also to determine the role of P-glycoprotein (P-gp) on mediating drug-drug interactions with MDMA. Bi-directional transport studies were conducted across MDCK-MDR1 and Caco-2 monolayers. MDMA brain and plasma levels were measured in P-gp deficient [mdr1a(-/-)] and normal [mdr1a(+/+)] mice after a 5 mg/kg i.p. dose of MDMA. Sprague-Dawley rats were pretreated with fluoxetine (4 days, 10 mg/kg, i.p.) or saline followed by MDMA (10 mg/kg, p.o.) and brain and plasma samples were collected over 10 h. MDMA and its active metabolite MDA were quantified using a HPLC method with fluorescence detection. In transport studies MDMA exhibited high permeability with essentially unpolarized transport. No significant difference in MDMA and MDA brain levels were seen in P-gp deficient versus normal mice. Pretreatment of rats with fluoxetine resulted in an increase in MDMA (1.4-fold) and MDA (1.5-fold) exposure in both brain and plasma. Elimination half-life was increased for MDMA (2.4 vs. 4.9 h) and MDA (1.8 vs. 8.2 h) with fluoxetine pretreatment. P-gp does not play a physiologically relevant role in absorption and distribution of MDMA, hence this transporter may not have a role in drug-drug interactions with MDMA. Fluoxetine pretreatment to provide protection from MDMA induced long term neurotoxicity decreases elimination of MDMA and MDA and may lead to enhanced risk of MDMA acute toxic effects. Overall, our results indicate that caution need to be practiced when recommending fluoxetine as an agent to provide protection from MDMA induced long term neurotoxicity.     

Use of peripheral dose data from uniform dynamic multileaf collimation fields to estimate out-of-field organ dose in patients treated employing sliding window intensity-modulated radiotherapy

Peripheral doses (PD) from uniform dynamic multileaf collimation (DMLC) fields were measured for 6 MV x-rays on a Varian linear accelerator using a 0.6 cc ionization chamber inserted at 5 cm depth into a 35 x 35 x 105 cm3 plastic water phantom. PD measurements were also carried out under identical conditions for seven patients treated for head and neck and cervical cancer employing sliding window intensity-modulated radiotherapy (IMRT). The measured PD from these patient-specific intensity-modulated beams (IMBs) were compared with the corresponding data from uniform DMLC fields having similar jaws setting. The measured PD per monitor unit (PD/MU) decreases almost exponentially with out-of-field distance for all uniform DMLC and static fields. For the same strip field width of 1.2 cm, uniform DMLC fields with a larger size of 14 x 22 cm2 deliver an average of 3.51 (SD = 0.51) times higher PD/MU at all out-of-field distances compared to 6 x 6 cm2. Similar to uniform DMLC fields, PD/MU measured from different patient-specific IMBs was found to decrease almost exponentially with out-of-field distance and increase with increase in field dimension. PD per MU from uniform DMLC fields and patient-specific IMBs having similar jaws setting shows good agreement (+/-7%) except at the most proximal distance, where a variation of more than 10% (maximum 15%) was observed. Our study shows that PD data generated from uniform DMLC fields can be used as baseline data to estimate out-of-field critical organ or whole-body dose in patients treated employing sliding window IMRT if an appropriate correction factor for field dimension is applied. The whole-body dose information can be used to estimate the possible increase in risk of fatal secondary malignancy in patients treated employing sliding window IMRT.     

Optimal control study to enhance oil production in labscale Vapex by varying solvent injection pressure with time

In this study, we determine and validate optimal policies of solvent injection pressure versus time to enhance oil production in labscale Vapex or vapor extraction of heavy oil. The study utilizes propane as solvent for a heavy oil of viscosity 14 500 mPa s. The necessary conditions for maximum oil production are derived using a detailed mass transfer model with interfacial solvent concentration versus time as a control function. Based on these conditions, a computational algorithm is developed and implemented to determine the optimal control, which is then converted into the optimal policy of solvent injection pressure versus time using experimental data. The experiments demonstrate that the optimal policy enhances oil production by 20–37% compared with that using constant solvent injection pressure. Moreover, the average deviation of the optimally calculated oil production from its experimental counterpart, both obtained using the same optimal solvent injection policy, is found to be a low value of 4.8%. Copyright © 2015 John Wiley & Sons, Ltd.     

Estimation of risk of radiation-induced carcinogenesis in adolescents with nasopharyngeal cancer treated using sliding window IMRT.

PURPOSE: To estimate the risk of radiation-induced carcinogenesis based on whole-body dose measurement on adolescent patients undergoing intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: Ten adolescent patients with nasopharyngeal cancer were planed and treated to a dose of 70.2 Gy using sliding window IMRT. Peripheral dose (PD) was measured using thermoluminescent dosimeters kept at anterior, lateral and posterior positions of each axial plane at the level of xiphoid process, umbilicus and gonads of every patient. The associated risk of radiation-induced carcinogenesis was estimated based on the measured whole-body dose and using age- and sex-specific ICRP-60 nominal probability coefficient of 7.5% (boys) and 9.5% (girls) per Sv. RESULTS: In all patients, measured PD per monitor unit (MU) decreases almost exponentially with out-of-field distance and varies with gantry angle. Highest whole-body dose equivalent ranged from 0.5318 to 0.9867 Sv (mean=0.8141 Sv, SD=0.138) which was measured posteriorly at the level of xiphoid process. Whole-body dose was represented by the average dose at xiphoid process and all measurement positions ranged from 0.3661 to 0.8766 Sv (mean=0.658 Sv, SD=0.16) and 0.2267 to 0.5277 Sv (mean=0.3859 Sv, SD=0.09), respectively. The associated mean risk of radiation-induced carcinogenesis estimated based on different representation of mean whole-body dose was 6.57%, 5.3% and 3.11%, respectively. Higher mean risk of 7.32% was estimated among girls as compared to 6.25% for boys. CONCLUSIONS: Knowledge of risk of secondary malignancy is particularly important in adolescents and should be considered when choosing the optimal treatment technique and delivery system.     

Evaluation of indirect immunofluorescent antibody test for detection of IgM specific antibodies in malaria.

Indirect immunofluorescent antibody test using Plasmodium falciparum antigen from in vitro culture was evaluated for detecting IgM antibodies in order to determine the feasibility of its application in serodiagnosis of malaria. Test was compared with the already adapted IgG-IIF test using the same antigen. It was found that none of the healthy controls and slide negative fever cases had malaria IgM antibodies whereas 8 per cent of healthy controls and 49.01 per cent of the slide negative fever cases had malaria IgG antibodies. The sensitivity of IgM-IIF test was 94.68 per cent and that of IgG-IIF test was 96.81 per cent. IgM antibodies could be detected very early even on the first day of fever and titre rose gradually with increasing number of days of illness before institution of treatment. The IgM antibodies, being short lasting are able to reflect recent infection. The test although highly sensitive and specific is laborious and expensive. Therefore, it may be used as a serodiagnostic test in advanced laboratories only for confirmation of selected slide negative cases.