Studies in the phototaxis of rhodospirillum rubrum

The bacterium Rhodospirillurn rubrum is capable of a photosynthetic reduction of CO2 similar to plant photo­ synthesis. A decrease in the illumination of R. rubrum induces it to reverse its direction of swimming; an investigation of the probability of this phototactic response as a function of the parameters of the stimulus, such as the intensity of illumination and its time pattern, should enhance our understanding of biological irritability. The present investigation is preliminary to such an undertaking. It was attempted to learn more about the responding system through studies of the interaction between the pigments, phototaxis, and metabolism of R. rubrum. A determination was made of the relative spectral effectiveness of light in promoting a phototactic response; this measurement provided evidence that in addition to bacteriochlorophyll the predominant carotenoid pigment of rubrum absorbs phototactically active light. It has been suggested that the tactic response of R. rubrum is associated directly with a decrease in its metabolic rate; studies of the tactic response to oxygen yielded evidence that this hypothesis must be abandoned. The remarkable adherence to the Weber Law reportedly displayed in the phototaxis of R. rubrum was reinvesti­gated; an adherence over a much smaller range of intensities was observed than had been reported earlier. The masking, under certain conditions of a potentially close Weber Law adherence was discussed.</p

A PI3K p110β–Rac signalling loop mediates Pten-loss-induced perturbation of haematopoiesis and leukaemogenesis

The tumour suppressor PTEN, which antagonizes PI3K signalling, is frequently inactivated in haematologic malignancies. In mice, deletion of PTEN in haematopoietic stem cells (HSCs) causes perturbed haematopoiesis, myeloproliferative neoplasia (MPN) and leukaemia. Although the roles of the PI3K isoforms have been studied in PTEN-deficient tumours, their individual roles in PTEN-deficient HSCs are unknown. Here we show that when we delete PTEN in HSCs using the Mx1–Cre system, p110β ablation prevents MPN, improves HSC function and suppresses leukaemia initiation. Pharmacologic inhibition of p110β in PTEN-deficient mice recapitulates these genetic findings, but suggests involvement of both Akt-dependent and -independent pathways. Further investigation reveals that a p110β–Rac signalling loop plays a critical role in PTEN-deficient HSCs. Together, these data suggest that myeloid neoplasia driven by PTEN loss is dependent on p110β via p110β–Rac-positive-feedback loop, and that disruption of this loop may offer a new and effective therapeutic strategy for PTEN-deficient leukaemia

Panentheism and the undoing of disenchantment

In this article I draw on historical and conceptual arguments to show, first, that disenchantment and the influential view of the relationship between science and religion to which disenchantment gives rise are rooted in the metaphysics of theism. I then introduce the alternative metaphysical position of panentheism and identify Jungian psychology as an important, if implicit, mid-twentieth-century instance of panentheistic thought. Using the example of Jungian psychology, I demonstrate how the viewpoint of panentheism undoes the implications of disenchantment for the relationship between science and religion, promoting greater opportunities for dialogue and reconciliation between science and religion. I note, however, that these closer relations may depend on understanding science and religion differently from how they are understood under disenchantment. While the original tension between science and religion is eased, another tension – between panentheistic and disenchanted understandings of science and religion – is exposed. I conclude by reflecting on some implications of this discussion for sociology

Association football and the representation of homosexuality by the print media: a case study of Anton Hysén

In March 2011 Anton Hysén (a semi-professional footballer currently playing in the Swedish fourth division) became only the second association football (soccer) player of any professional disposition to publicly declare his homosexuality whilst still playing the game. This article provides a textual analysis of the print media’s reaction to Hysén coming out and examines whether, in 2011, they portray more inclusive notions towards homosexuality than they did in 1990 when British footballer Justin Fashanu came out. The results advance inclusive masculinity theory as a number of print media sources (mostly British) interview Hysén in the weeks immediately after he came out and publish articles that challenge homophobia. Highlighting a change since 1990, a significant number of articles stress the need for the key stakeholders in football (players, fans, clubs, agents, the authorities and the media) to accept gay players

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome

Competition between light and dark Metabolism in Rhodospirillum rubrum

Rhodospirillum rubrum in the dark carries op.t a respiratory metabolism; the oxidation, by O2, of an organic substrate provides energy which is needed for anabolic processes. In strong light the metabolism is strictly photosynthetic; the organic substrate donates hydrogen to an oxidizing substance produced in photosynthesis, and no uptake of oxygen is observe!i. These ,processes have been discussed in detail in an earlier paper (CLAYTON 1955}; one can anticipate that in weak light a competition will exist between photosynthetic and respiratory metabolism: hydrogen from the substrate will be transferred partly to the oxidizing substance of photosynthesis and partly to molecular oxygen. The purpose of the present paper is to describe this competition quantitatively.This work has been supported in part by the Office of Naval Research