Contrast column interruption artefact in computed tomography pulmonary angiography

Interruption of the contrast column during inspiration can lead to non‐diagnostic CT pulmonary angiograms. The importance of this artefact will increase with more CT studies being performed for pulmonary embolism on multidetector row CT. We describe here an instance of such an artefact and discuss its aetiology.     

Association between home working and mental health by key worker status during the Covid-19 pandemic. Evidence from four British longitudinal studies

Little is known about the relationship between homeworking and mental health during the Covid-19 pandemic and how it might differ by keyworker status. To understand this relationship, we use longitudinal data collected over three time points during the pandemic from three British cohort studies born in 1958 (National Child Development Study), 1970 (British Cohort Study) and 1989–90 (Next Step) as well as from a population-based study stratified by four age groups (Understanding Society). We estimate the association between life satisfaction, anxiety, depression, and psychological distress and homeworking by key worker status using mixed effects models with maximum likelihood estimation to account for repeated measurements across the pandemic, allowing intercepts to vary across individuals after controlling for a set of covariates including pre-pandemic home working propensities and loneliness. Results show that key workers working from home showed the greatest decline in mental health outcomes relative to other groups. Pre-pandemic homeworking did not significantly change the nature of such a relationship and loneliness slightly attenuated some of the effects. Finally, mental health outcomes varied across age-groups and time points. The discussion emphasises the need to pay attention to key workers when assessing the relationship between mental health and homeworking.     

The effect of tridiphane (2-(3,5-dichlorophenyl)-2-(2,2,2-trichloroethyl)oxirane) on hepatic epoxide-metabolizing enzymes: indications of peroxisome proliferation

Administration of tridiphane (Tandem, DOWCO 356, 2-(3,5-dichlorophenyl)-2-(2,2,2-trichloroethyl)oxirane) to male Swiss-Webster mice for 3 days at 100, 250, and 500 mg/kg (ip) resulted in increases in liver weight accompanied by an increase in mitotic index and increases in large particle and microsomal protein. Epoxide hydrolase (EH) activity towards cis-stilbene oxide (CSO, microsomal EH) was elevated in microsomes and cytosol, a decrease in microsomal cholesterol EH was found, and hydrolysis of trans-stilbene oxide (TSO, cytosolic EH) was elevated in the cytosol but not in the microsomes. Glutathione S-transferase (GST) activity was elevated in cytosol for CSO, TSO, and 1,2-dichloro-4-nitrobenzene (DCNB), with inconsistent responses found with 1-chloro-2,4-dinitrobenzene (CDNB) and 1,2-epoxy-3-(p-nitrophenoxy)propane (ENPP). Microsomal GST was not consistently effected by tridiphane. Clofibrate (500 mg/kg, 3 daily ip injections) treatment resulted in similar responses in liver size, microsomal protein, and the EHs. The increase in cytosolic EH activity previously has been noted only in animals treated with peroxisome proliferators. Examination of livers from mice treated with 250 mg/kg tridiphane revealed that an increase in hepatic peroxisomes was apparent after 3 days of treatment. This was accompanied by decreases in serum cholesterol and triglyceride levels and increases in liver carnitine acetyl transferase and cyanide-insensitive oxidation of palmitoyl-CoA. This study demonstrates that tridiphane does have in vivo effects on mammalian epoxide-metabolizing enzymes and extends the association of increased cytosolic epoxide hydrolase activity with peroxisome proliferation.     

Dietary intake and micronutrient deficiency in children with cancer

Data regarding micronutrient deficiencies in children with cancer are lacking. We measured micronutrients in a subset of children with cancer (n = 23) participating in a randomized trial of the neutropenic diet. Ninety‐six percent of children had ≥1 micronutrient deficiency and 39% had ≥3 micronutrient deficiencies. Eighty‐six percent of children had vitamin C deficiency, 87% had 25‐hydroxyvitamin D deficiency, 50% had zinc deficiency, and 13% had vitamin A deficiency. Dietary intake did not correlate with micronutrient deficiency status. More data are needed regarding the prevalence and etiology of micronutrient deficiencies in children with cancer to further understand their implications and treatment.     

Occurrence of Flavonol Sulphates in Alchornea laxiflora

For the first time, quercetin-3',4'-disulphate (1) and another novel flavonol sulphate quercetin-7,4'-disulphate (2) were isolated from an ethyl acetate-soluble fraction of the crude methanol extract of Alchornea laxiflora. Purification of these compounds was carried out by column chromatography utilising Sephadex LH 20 with 30% toluene in ethanol as eluent. Structural elucidation was by UV, IR, 1 H-NMR and 13 C-NMR spectroscopy as well as by FAB-MS.     

The Efficacy of DFO-HOPO,DTPA-DX and DTPA for Enhancing the Excretion of Plutonium and Americium from the Rat

Summary

A hydroxypridinone derivative of desferrioxamine (Na-DFO-HOPO), a dihydroxamic derivative of diethylenetriaminepenta-acetic acid (ZnNa-DTPA-DX), and DTPA (CaNa₃- and ZnNa₃-DTPA) were tested at dosages of 30 μmol kg^?1 for their ability to remove ²³⁸Pu or ²⁴¹Am from rats after their intravenous injection as citrate or inhalation as nitrate. The most effective treatment regimen for injected Pu was the repeated administration of DFO-HOPO; by 7 days the body content was reduced to 8% of that in untreated animals. Repeated dosages of 3 μmol kg^?1 DFO-HOPO were as effective as those of 30 μmol kg^?1 DTPA. After inhalation of Pu nitrate, repeated treatment with DTPA, DTPA-DX or DFO-HOPO reduced the body content by 7 days to, respectively, 10, 15 and 31% of those in untreated animals. After inhalation of Am, DTPA-DX and DTPA were equally effective, the body contents being reduced to 7% of control values with repeated treatment. Injection of DFO-HOPO was ineffective for enhancing the elimination of inhaled or injected Am. The results confirm the strategy of examining the use of siderophore analogues for the decorporation of Pu or Am. However, at present DTPA should remain the agent of choice, particularly after inhalation.