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Using a low density culture technique which allows normal human peripheral blood T cells to proliferate actively in vitro when stimulated by mitogens, it is shown that dexamethasone enhances the spontaneous induction of cells bearing receptors for the Fc of IgM. Dexamethasone has no effect on the induction of cells bearing receptors for the Fc of IgG. [ABSTRACT FROM AUTHOR]

Previous studies have described reverse-transcription loop-mediated isothermal amplification (RT-LAMP) for the rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal/oropharyngeal swab and saliva samples. This multisite clinical evaluation describes the validation of an improved sample preparation method for extraction-free RT-LAMP and reports clinical performance of four RT-LAMP assay formats for SARS-CoV-2 detection. Direct RT-LAMP was performed on 559 swabs and 86,760 saliva samples and RNA RT-LAMP on extracted RNA from 12,619 swabs and 12,521 saliva samples from asymptomatic and symptomatic individuals across health care and community settings. For direct RT-LAMP, overall diagnostic sensitivity (DSe) was 70.35% (95% CI, 63.48%-76.60%) on swabs and 84.62% (95% CI, 79.50%-88.88%) on saliva, with diagnostic specificity of 100% (95% CI, 98.98%-100.00%) on swabs and 100% (95% CI, 99.72%-100.00%) on saliva, compared with quantitative RT-PCR (RT-qPCR); analyzing samples with RT-qPCR ORF1ab C T values of ≤25 and ≤33, DSe values were 100% (95% CI, 96.34%-100%) and 77.78% (95% CI, 70.99%-83.62%) for swabs, and 99.01% (95% CI, 94.61%-99.97%) and 87.61% (95% CI, 82.69%-91.54%) for saliva, respectively. For RNA RT-LAMP, overall DSe and diagnostic specificity were 96.06% (95% CI, 92.88%-98.12%) and 99.99% (95% CI, 99.95%-100%) for swabs, and 80.65% (95% CI, 73.54%-86.54%) and 99.99% (95% CI, 99.95%-100%) for saliva, respectively. These findings demonstrate that RT-LAMP is applicable to a variety of use cases, including frequent, interval-based direct RT-LAMP of saliva from asymptomatic individuals who may otherwise be missed using symptomatic testing alone., (Copyright © 2022 Association for Molecular Pathology and American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

The COVID-19 pandemic has illustrated the importance of simple, rapid and accurate diagnostic testing. This study describes the validation of a new rapid SARS-CoV-2 RT-LAMP assay for use on extracted RNA or directly from swab offering an alternative diagnostic pathway that does not rely on traditional reagents that are often in short supply during a pandemic. Analytical specificity (ASp) of this new RT-LAMP assay was 100% and analytical sensitivity (ASe) was between 1 × 10 1 and 1 × 10 2 copies per reaction when using a synthetic DNA target. The overall diagnostic sensitivity (DSe) and specificity (DSp) of RNA RT-LAMP was 97% and 99% respectively, relative to the standard of care rRT-PCR. When a C T cut-off of 33 was employed, above which increasingly evidence suggests there is a low risk of patients shedding infectious virus, the diagnostic sensitivity was 100%. The DSe and DSp of Direct RT-LAMP (that does not require RNA extraction) was 67% and 97%, respectively. When setting C T cut-offs of ≤33 and ≤25, the DSe increased to 75% and 100%, respectively, time from swab-to-result, C T < 25, was < 15 min. We propose that RNA RT-LAMP could replace rRT-PCR where there is a need for increased sample throughput and Direct RT-LAMP as a near-patient screening tool to rapidly identify highly contagious individuals within emergency departments and care homes during times of increased disease prevalence ensuring negative results still get laboratory confirmation., (Crown Copyright © 2020. Published by Elsevier Ltd. All rights reserved.)

A comparison of the Roche Cobas Core and Hybritech TANDEM-E PSA (prostate specific antigen) assays revealed a large difference in the reactivity of each assay to the separated free and complexed forms of serum PSA in patients with prostatic carcinoma. The Roche assay was relatively much more responsive to the free form, but the Hybritech assay was relatively more responsive to the complexed form and total serum PSA. It is possible that the adoption of a universal standard for PSA will not completely resolve the disagreement between PSA assay on individual patient samples, and the use of separate assays for the free and complexed forms may be necessary for the further clinical development of PSA as a tumour marker.

A catechol enzyme electrode is described, in which a Clark-type oxygen electrode is coupled to immobilised polyphenol oxidase in albumin cross linked with glutaraldehyde on a dialysis membrane. Electrode calibration, response time, pH response profile, stability, detection limit and selectivity are evaluated and the feasibility of using the electrode for the measurement of catecholamines in the urine of patients with neural crest tumours is assessed.

An 'anti-oestrogen' such as tamoxifen may protect prophylactically against breast cancer. At the Royal Marsden Hospital, the blind randomised feasibility study of tamoxifen 20 mg per day versus placebo in 200 healthy women has been extended into a pilot trial. A total of 435 women with a family history of breast cancer have been accrued. Compliance, acute toxicity, clotting factors, lipids and bone mass were assessed. The pilot trial has confirmed the findings of the feasibility study. Compliance was high and the frequency of side-effects was similar in both groups, except for a significant increase in hot flushes in the tamoxifen-treated women (33 vs. 17%). Bone mass and clotting factors were not affected. Tamoxifen significantly reduced serum cholesterol, low-density lipoprotein cholesterol (LDLC) and apolipoprotein B levels in post-menopausal women. In premenopausal women, the effects on lipids and lipoproteins was smaller with a significant fall in total serum cholesterol and LDLC only. The trial has approval to accrue up to 1000 women.

High dose melphalan (HDM, 140 mg/m2 i.v.) has been evaluated in 58 patients under 63 years with multiple myeloma. Among previously untreated patients 11/41 (27%) entered a complete remission (CR: no measurable myeloma protein and a normal bone marrow) and 21 (51%) entered a partial remission (more than 50% reduction in myeloma protein and improvement in all other features). Median duration of remission is 19 months. Two patients who had responded to previous conventional treatment entered CR after HDM. Among 15 patients who had failed on previous chemotherapy the response rate was 66% including two CRs. However, in this group all patients have relapsed within 1 year. Profound myelosuppression, moderate nausea, vomiting, mucositis and diarrhoea with reversible alopecia occurred in all patients. There were 10 deaths within 2 months of treatment mainly due to sepsis and haemorrhage. In a subsequent study, high dose methyl prednisolone (1 g/m2 daily for 5 d) has been added to HDM. Response rates are similar with 6/22 (27%) CR, 13/22 (59%) PR and 2/22 NR but there was only one early death, reflecting improvements in medical management. The high CR rate is an encouraging feature of this approach which is now to be the basis of a prospective trial sponsored by the Medical Research Council in which HDM, with and without steroids, is compared to the best available conventional therapy (the MRC VI Myelomatosis trial).

Following PHA-stimulation of lymphocytes in culture, it is known that nuclear RNA synthesis and the amount of extractable RNA polymerase activity rise in these cells. The relationship between these two phenomena has been examined. Using an in vitro assay system which discriminates between polymerase activity which is "engaged" in nuclear RNA synthesis and a pool of "free" enzyme, the data suggest that the factors regulating the interaction between these two pools of enzyme activity are different for forms I and II RNA polymerases.