Haematological malignancy and nosocomial transmission are associated with an increased risk of death from COVID-19: results of a multi-center UK cohort.

The COVID-19 pandemic has been a disruptive event for cancer patients, especially those with haematological malignancies (HM). They may experience a more severe clinical course due to impaired immune responses. This multi-center retrospective UK audit identified cancer patients who had SARS-CoV-2 infection between 1 March and 10 June 2020 and collected data pertaining to cancer history, COVID-19 presentation and outcomes. In total, 179 patients were identified with a median age of 72 (IQR 61, 81) and follow-up of 44 days (IQR 42, 45). Forty-one percent were female and the overall mortality was 37%. Twenty-nine percent had HM and of these, those treated with chemotherapy in the preceding 28 days to COVID-19 diagnosis had worse outcome compared with solid malignancy (SM): 62% versus 19% died [HR 8.33 (95% CI, 2.56-25), p p = 0.001). Patients with haematological malignancies and those who acquire nosocomial transmission are at increased risk of death. Therefore, there is an urgent need to reassess shielding advice, reinforce stringent infection control, and ensure regular patient and staff testing to prevent nosocomial transmission

Distinct frequency preferences of different types of rat hippocampal neurones in response to oscillatory input currents

Coherent network oscillations in several distinct frequency bands are seen in the hippocampus of behaving animals. To investigate how different neuronal types within this network respond to oscillatory inputs we made whole-cell current clamp recordings from three different types of neurones in the CA1 region of rat hippocampal slices: pyramidal cells, fast-spiking interneurones and horizontal interneurones, and recorded their response to sinusoidal inputs at physiologically relevant frequencies (1-100 Hz).Pyramidal neurones showed firing preference to inputs at theta frequencies (range 2-7 Hz; n = 30). They showed subthreshold resonance in the same frequency range (2-7 Hz; mean 4.1 ± 0.4 Hz; n = 19).Interneurones differed in their firing properties. Horizontal interneurones in the stratum oriens showed firing preference to inputs at theta frequencies (range 1.5-10 Hz; n = 10). These interneurones also showed resonance at low frequencies (range 1-5 Hz; mean 2.4 ± 0.5 Hz; n = 7). In contrast, fast-spiking interneurones with cell bodies in the pyramidal cell layer fired preferentially at input frequencies in the gamma band (range 30-50 Hz; n = 10/12). These interneurones showed resonance at beta-gamma frequencies (10-50 Hz; mean 26 ± 5 Hz; n = 7/8).Thus, in the hippocampus, different types of neurones have distinct frequency preferences. Therefore, in the CA1 layer of the hippocampal network, a compound oscillatory input may be segregated into distinct frequency components which are processed locally by distinct types of neurones

Management of suspected herpes simplex virus encephalitis in adults in a UK teaching hospital

The outcome of herpes simplex virus (HSV) encephalitis is improved with prompt initiation of aciclovir treatment. Delays are common, but there is little understanding of why they occur. The case notes of 21 adults admitted with suspected HSV encephalitis over one year were reviewed. The median (range) duration of illness was 2.5 (1–99) days. Seventeen (81%) patients had a lumbar puncture (LP) performed, at a median (range) time of 24 (2–114) hours after encephalitis was suspected. Lumbar puncture was delayed for a computed tomography (CT) scan in 15 patients, but only one of these had contraindications to an immediate LP. The median (range) time from presentation to starting aciclovir was 48 (2–432) hours. HSV-PCR (polymerase chain reaction) was requested on cerebrospinal fluid from 12 patients, one of whom was positive. Five (24%) patients were given the wrong dose of aciclovir. Overall the management of suspected HSV encephalitis was often sub-optimal, with delays in LP occurring due to unnecessary CT scans, and the wrong aciclovir dose administered. Guidelines for the management of suspected encephalitis are needed

Effects of Steroid Hormones on Sex Differences in Cerebral Perfusion

Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS) as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women). Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women