Propranolol reduces IFN-γ driven PD-L1 immunosuppression and improves anti-tumour immunity in ovarian cancer

The immune system plays an important role in controlling epithelial ovarian cancer (EOC). EOC is considered to be a "cold tumour," a tumour that has not triggered a strong response by the immune system. However, tumour infiltrating lymphocytes (TILs) and the expression of programmed cell death ligand (PD-L1) are used as prognostic indicators in EOC. Immunotherapy such as PD-(L)1 inhibitors have shown limited benefit in EOC. Since the immune system is affected by behavioural stress and the beta-adrenergic signalling pathway, this study aimed to explore the impact of propranolol (PRO), a beta-blocker, on anti-tumour immunity in both in vitro and in vivo EOC models. Noradrenaline (NA), an adrenergic agonist, did not directly regulate PD-L1 expression but PD-L1 was significantly upregulated by IFN-γ in EOC cell lines. IFN-γ also increased PD-L1 on extracellular vesicles (EVs) released by ID8 cells. PRO significantly decreased IFN-γ levels in primary immune cells activated ex vivo and showed increased viability of the CD8⁺ cell population in an EV-immune cell co-incubation. In addition, PRO reverted PD-L1 upregulation and significantly decreased IL-10 levels in an immune-cancer cell co-culture. Chronic behavioural stress increased metastasis in mice while PRO monotherapy and the combo of PRO and PD-(L)1 inhibitor significantly decreased stress-induced metastasis. The combined therapy also reduced tumour weight compared to the cancer control group and induced anti-tumour T-cell responses with significant CD8 expression in tumour tissues. In conclusion, PRO showed a modulation of the cancer immune response by decreasing IFN-γ production and, in turn, IFN-γ-mediated PD-L1 overexpression. The combined therapy of PRO and PD-(L)1 inhibitor decreased metastasis and improved anti-tumour immunity offering a promising new therapy.

[A man with pink urine]

A 44-year-old male was submitted to the Intensive Care Unit after a drug intoxication with respiratory depression. Pink urine was observed after 20 hours of use of propofol for sedation. This phenomena is named 'pink urine syndrome' and is occasionally seen after sedation with propofol caused by an upregulated urate excretion in the urine.

Phase I randomized trial of liothyronine for remyelination in multiple sclerosis: A dose-ranging study with assessment of reliability of visual outcomes

BACKGROUND

Thyroid hormone promotes remyelination in multiple sclerosis (MS) animal models through a variety of mechanisms. Liothyronine (L-T3) is a short-acting thyroid hormone with demonstrated safety and tolerability for short-term and chronic use in euthyroid adults with other health conditions, but has not been studied in people with MS. The objectives of this single-center, phase I, placebo-controlled, clinical trial were to determine the safety, tolerability, and optimal dosing of L-T3 in people with MS in preparation for a phase 2 remyelination clinical trial. Secondary goals included exploration of the reliability of functional and clinical measurements of myelination in the anterior visual pathway over one week.

METHODS

Groups of six clinically stable people with MS were randomized in a 4:2 ratio to receive L-T3 or placebo. The first group received 50 mcg total daily dose (TDD) of L-T3, with escalating doses of L-T3 in subsequent groups, up to potentially 150 mcg TDD in the final group. Prior to enrollment for the next dose-escalated group, all safety measures for the prior dose were reviewed. The maximum tolerated dose (MTD) was considered to be the dose below which two or more participants experienced dose limiting symptoms or one participant experienced a serious adverse event. After the MTD was reached, no further patients were enrolled. Visual evoked potentials (VEP) P100 latency with two different check sizes (17' and 34') and Sloan low contrast letter acuity (LCLA) were measured pre- and post-treatment. To determine whether there was a treatment effect, the placebo and L-T3 groups were compared using a clustered bootstrap regression estimation. A linear mixed effects model was used to determine test-retest reliability of VEP and LCLA in all eyes.

RESULTS

Between May 2016 and November 2016, 15 people with MS were randomized to L-T3 (n = 10) or placebo (n = 5). Subjects were adherent to the study drug and the MTD was 75 mcg TDD. No serious adverse events were observed and the most common adverse events were poor sleep and loose stools. No treatment effect of L-T3 was observed over one week. Therefore, data from patients on L-T3 and placebo were pooled to explore VEP and LCLA reliability. The intraclass correlations of VEP 17', VEP 34' and LCLA were 0.836, 0.860, and 0.932, respectively. The mean differences in values between visits 1 and 2 for VEP 17' and 34' and LCLA were 1.9 ms/eye (SD 6.5), 0.4 ms/eye (6.3), and 0.8/eye (3.6), respectively.

CONCLUSIONS

This study confirms the short-term safety and tolerability of L-T3 in people with MS, with 75 mcg TDD as the MTD. Our results also support that, despite small variations over one week, VEP with various check sizes and Sloan LCLA are reliable functional and clinical outcome measures that could be used in remyelination clinical trials in MS. A future phase 2 clinical trial to investigate the efficacy of L-T3 as a remyelination therapy may be warranted. This trial was registered on clinicaltrials.gov (NCT02760056).

A Survey of American Thyroid Association Members Regarding the 2015 Adult Thyroid Nodule and Differentiated Thyroid Cancer Clinical Practice Guidelines

Background: The 2015 American Thyroid Association (ATA) clinical practice guidelines (CPGs) on management of thyroid nodules (TNs) and differentiated thyroid cancer (DTC) in adults were developed to inform clinicians, patients, researchers, and health policy makers about the best available evidence, and its limitations, relating to management of these conditions. Methods: We conducted a cross-sectional electronic survey of ATA members' perspectives of these CPGs, using a standardized survey (Clinician Guidelines Determinant Questionnaire) developed by the Guidelines International Network. A survey link was electronically mailed to members in February of 2019, with reminders sent to nonrespondents 2 and 5 weeks later. Data were descriptively summarized, after excluding missing responses. Results: The overall response rate was 19.8% (348/1761). The effective response rate was 20.2% (348/1720), after excluding a recently deceased member and individuals who had either invalid e-mail addresses or whose e-mails were returned. Of the respondents, 37.9% (132/348) were female, 60.4% (209/346) were endocrinologists, 27.5% (95/346) were surgeons, and 3.5% (12/346) were nuclear medicine specialists. The majority of respondents (71.9%; 250/348) were at a mid- or advanced-career level, and more than half were in academia (57.5%; 195/339). The majority (69.8%; 243/348) practiced in North America. The vast majority of respondents indicated that the CPGs explained the underlying evidence (92.3%; 298/323) and 92.9% (300/323) agreed or strongly agreed with the content. Most respondents stated that they regularly used the CPGs in their practice (83.0%; 268/323). Most respondents (83.0%; 268/323) also agreed or strongly agreed that the recommendations were easy to incorporate in their practice. The most popular CPG format was an electronic desktop file (78.8%; 252/320). Shorter more frequent CPGs were favored by 55.0% (176/320) of respondents, and longer traditional CPGs were favored by 39.7% (127/320). Conclusions: The clinical content and evidence explanations in the adult TN and DTC CPGs are widely accepted and applied among ATA survey respondents. Future ATA CPG updates need to be optimized to best meet users' preferences regarding format, frequency, and length.

Is hypnotherapy an acceptable treatment option for children with habit cough?

Habit cough is a chronic, persistent dry cough which occurs in children only when awake. It is considered functional (non-organic) and can have a significant impact on the quality of life of the child and their family. One possible treatment option for habit cough is hypnotherapy. At our centre we offered hypnotherapy sessions to patients diagnosed with habit cough, and conducted telephone interviews with patients' parents to determine the acceptability of this therapy. Nine patients' parents were interviewed, and despite being unsure of what to expect with hypnotherapy, all nine found it an acceptable treatment option. Parents reported that hypnotherapy appeared to result in cough reduction or cessation in 6 out of 9 cases.

2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis

BACKGROUND

Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This document describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspecialty physicians and others providing care for patients with this condition.

METHODS

The American Thyroid Association (ATA) previously cosponsored guidelines for the management of thyrotoxicosis that were published in 2011. Considerable new literature has been published since then, and the ATA felt updated evidence-based guidelines were needed. The association assembled a task force of expert clinicians who authored this report. They examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to update the 2011 text and recommendations. The strength of the recommendations and the quality of evidence supporting them were rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group.

RESULTS

Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' orbitopathy; and management of other miscellaneous causes of thyrotoxicosis. New paradigms since publication of the 2011 guidelines are presented for the evaluation of the etiology of thyrotoxicosis, the management of Graves' hyperthyroidism with antithyroid drugs, the management of pregnant hyperthyroid patients, and the preparation of patients for thyroid surgery. The sections on less common causes of thyrotoxicosis have been expanded.

CONCLUSIONS

One hundred twenty-four evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.

Creating an institutional resource for research education and career development: a novel model from Oregon Clinical and Translational Research Institute

We have created an education and career development program within the CTSA structure at OHSU that serves the entire institution. We believe that this is unusual in scope among CTSA programs and has contributed to an increase in career development funding and research skills among fellows and faculty. While the key element is the institutional scope, important elements include: Tailoring programs of emphasis to points of inflection on the career pathway. Minimizing barriers to education by creating a flexible, tuition-free program. An integrated one-stop education and career development approach. An institutional program for career development award applicants as well as recipients. This career development program was developed within the context of a midsize health science university but the overall strategy may be applied to other CTSAs to simplify and reduce costs of education program development.

Extensions, validation, and clinical applications of a feedback control system simulator of the hypothalamo-pituitary-thyroid axis

BACKGROUND

We upgraded our recent feedback control system (FBCS) simulation model of human thyroid hormone (TH) regulation to include explicit representation of hypothalamic and pituitary dynamics, and updated TH distribution and elimination (D&E) parameters. This new model greatly expands the range of clinical and basic science scenarios explorable by computer simulation.

METHODS

We quantified the model from pharmacokinetic (PK) and physiological human data and validated it comparatively against several independent clinical data sets. We then explored three contemporary clinical issues with the new model: combined triiodothyronine (T(3))/thyroxine (T(4)) versus T(4)-only treatment, parenteral levothyroxine (L-T(4)) administration, and central hypothyroidism.

RESULTS

Combined T(3)/T(4) therapy--In thyroidectomized patients, the L-T(4)-only replacement doses needed to normalize plasma T(3) or average tissue T(3) were 145 microg L-T(4)/day or 165 microg L-T(4)/day, respectively. The combined T(4) + T(3) dosing needed to normalize both plasma and tissue T(3) levels was 105 microg L-T(4) + 9 microg T(3) per day. For all three regimens, simulated mean steady-state plasma thyroid-stimulating hormone (TSH), T(3), and T(4) was within normal ranges (TSH: 0.5-5 mU/L; T(4): 5-12 microg/dL; T(3): 0.8-1.9 ng/mL). Parenteral T(4) administration--800 microg weekly or 400 microg twice weekly normalized average tissue T(3) levels both for subcutaneous (SC) and intramuscular (IM) routes of administration. TSH, T(3), and T(4) levels were maintained within normal ranges for all four of these dosing schemes (1x vs. 2x weekly, SC vs. IM). Central hypothyroidism--We simulated steady-state plasma T(3), T(4), and TSH concentrations in response to varying degrees of central hypothyroidism, reducing TSH secretion from 50% down to 0.1% of normal. Surprisingly, TSH, T(3), and T(4) plasma concentrations remained within normal ranges for TSH secretion as low as 25% of normal.

CONCLUSIONS

Combined T(3)/T(4) treatment--Simulated standard L-T(4)-only therapy was sufficient to renormalize average tissue T(3) levels and maintain normal TSH, T(3), and T(4) plasma levels, supporting adequacy of standard L-T(4)-only treatment. Parenteral T(4) administration-TSH, T(3), and T(4) levels were maintained within normal ranges for all four of these dosing schemes (1x vs. 2x weekly, SC vs. IM), supporting these therapeutic alternatives for patients with compromised L-T(4) gut absorption. Central hypothyroidism--These results highlight how highly nonlinear feedback in the hypothalamic-pituitary-thyroid axis acts to maintain normal hormone levels, even with severely reduced TSH secretion.

L-T4 bioequivalence and hormone replacement studies via feedback control simulations

FDA Guidance for testing bioequivalence of levothyroxine (L-T(4)) preparations has been challenged by several groups, based on multiple issues. The efficacy of single versus combined hormone therapy also is receiving additional scrutiny. To examine these concerns, we developed a new nonlinear feedback system simulation model of whole-body regulation mechanisms involving dynamics of T(3), T(4), TSH, plasma protein binding, extravascular regulatory enzyme systems, and the hypothalamic-pituitary-thyroid axis, all quantified from human data. To address bioequivalence, we explored how to best account for varying and unmeasured endogenous T(4) following dosing with exogenous oral L-T(4) in euthyroid volunteers in required pharmacokinetic (PK) studies, by simulating various dosing scenarios and developing a new and simple correction method. We computed and assessed dosing error effects and baseline corrections using simulator-predicted endogenous T(4) level variations, due to actual closed-loop effects, and compared these with approximate corrections computed directly from PK data. Predicted dose-responses were quite linear, and for constant baseline, 7-day half-life, and our new formula-correction methods, we established some bounds on bioequivalent dosages. Simulated replacement after thyroidectomy required 141 microg L-T(4) only to normalize T(3) tissue levels and 162 microg L-T(4) to normalize plasma T(3) levels. A combined dose of approximately 103 microg L-T(4) plus approximately 6 microg T(3) ( approximately 18:1 ratio) was needed to normalize both plasma T(3) and T(4) and average tissue T(3) levels. However, simulated average tissue T(3) levels were normalized with standard L-T(4)-only therapy, and plasma T(3) levels were still within the normal range. We suggest a simple and more accurate correction for endogenous T(4) in PK studies. Current standard L-T(4)-only treatment is supported for routine replacement needs.

Phase I study of irinotecan (Ir) and cisplatin (DDP) in combination with thoracic radiotherapy (RT), either twice daily (45 Gy) or once daily (70 Gy), in patients with limited (Ltd) small cell lung carcinoma (SCLC): Early analysis of RTOG 0241

7058

Background: Ir in combination with DDP has proven superior to DDP & VP-16 in extensive stage SCLC (Noda et al NEJM 1/02), with marked increase in 2 yr survival (19.5%, vs 5.2%). Hence, it is critical to determine if Ir can be safely & effectively integrated with concurrent RT and DDP in earlier stage, Ltd SCLC. Methods: 1° endpoint: Determine maximum tolerated dose (MTD) of Ir d 1 & 8 plus DDP 60 mg/m2 q 3 wks & either BID RT (45 Gy) or QD RT (70 Gy). Eligibility stipulated Tx-naïve patients (pts) with Ltd SCLC, PS 0–1, adequate heme (ANC ≤ 1500/mL; plts ≥ 120,000/mL) hepatic (bili ≤ 1.5/dL) & renal (creat ≤ 1.5gr/dL) function, & baseline FEV1 of ≥ 1 liter. Ir was escalated in sequential (seq) cohorts from 40 mg/m2 (level 1) to 50 mg/m2 (level 2) & then to 60 mg/m2 (level 3) d 1 & 8 q 3 wks during each cycle of treatment. Ir & DDP were given concurrently with RT for cycle 1 in seq A (45 Gy) & during cycles 1 & 2 in seq B (70 Gy). 36 pts were targeted for accrual. DLT was defined as gr 4 esophagitis, pneumonitis, or diarrhea; gr 4 neutropenic fever, or any attributable gr 5 toxicity Results: As of 12/05, 36 pts were accrued, (21 - seq A; 15 - seq B). Median age was 64 (range 49–79) Of 33 eval pts, 18 (55%) were female; 24 (73%) PS 0; 67% had ≤ 5% wt loss. Attributable DLT was not seen in seq A, but was observed in seq B (70 Gy) at 50 mg/m2 with 1 episode each of gr 4 diarrhea & esophagitis, necessitating hospitalization. In addition, 1 pt in seq B had non-attributable gr 4 cardiovascular AEs. There has been no acute gr 5 toxicity. 1 pt experienced late gr 3 pulm toxicity, another gr 3 constitutional toxicity, including wt loss. The overall incidence of gr 3 esophagitis was 34%. Conclusions: In Ltd SCLC, I at 60 mg/m2 d 1 & 8 is safe & feasible in combination with DDP 60 mg/m2 q 3 wks & BID RT (45 Gy). The MTD for I in combination with RT (70 Gy) & DDP 60 mg/m2 is 40 mg/m2 d 1 and 8. Response, progression, survival data remain immature.

[Table: see text]

[Table: see text]

A prospective, randomized, double-blind study of the tolerability of rifapentine 600, 900, and 1,200 mg plus isoniazid in the continuation phase of tuberculosis treatment

Once-weekly rifapentine 600 mg plus isoniazid (INH) during the continuation phase treatment of tuberculosis is associated with a relapse rate higher than that of twice-weekly rifampin plus INH. The safety and tolerability of higher rifapentine doses need to be determined. We conducted a prospective, randomized, double-blind trial of rifapentine at three doses (600, 900, and 1,200 mg) plus INH 15 mg/kg once weekly in the continuation phase treatment of culture-positive tuberculosis in 150 human immunodeficiency virus-seronegative adults. Outcome measures were discontinuation of therapy for any reason and adverse events on therapy. Treatment was discontinued in 3 of 52 (6%), 2 of 51 (4%), and 3 of 47 (6%) in the rifapentine 600-, 900-, and 1,200-mg treatment arms, respectively. Only one discontinuation, in the rifapentine 1,200-mg arm, was due to an adverse event possibly associated with study therapy. There was a trend toward more adverse events, possibly associated with study therapy, in the highest-dose arms (p = 0.051). Rifapentine 900-mg, once-weekly dosing appears to be safe and well tolerated and is being evaluated in Phase III efficacy trials of treatment of latent tuberculosis. Further evaluation of the safety and tolerability of rifapentine 1,200 mg is warranted.

Resuscitating paediatric induction: an action research approach

OBJECTIVES

To establish teaching objectives, methods and assessment for a paediatric induction programme.

DESIGN

Action research over a 2-year period.

PARTICIPANTS

88 doctors from three hospitals.

MAIN OUTCOME MEASURES

These were end-of-course evaluations, using Likert scales, and free comments; independent evaluation by the West Midlands Deanery 4 months after courses, in which participating and non-participating units were compared, and summative assessment of trainees involving multiple-choice questions, a basic life-support scenario and an illness scenario.

RESULTS

88 participants attended four 3-day courses over 2 years. Mean satisfaction ratings were very high for content, personal value, and presentation. There was a significant rise in Deanery evaluation scores, compared with non-significant change in other hospitals, and there were excellent pass rates for trainees.

CONCLUSIONS

Trainees strongly approve of induction with clear objectives, active teaching, and validated assessment.

Maternal behaviors associated with smothering: a preliminary descriptive study

OBJECTIVES

To describe maternal behavior in 15 women identified as having smothered their children.

DESIGN

A descriptive study of maternal behavior and interaction with her child, using videotapes of mother and child together. These were obtained by covert video surveillance in a hospital setting. Maternal behavior was rated using an assessment schedule designed to be used with video.

RESULTS

The mothers showed a range of behaviors. Three groups emerged; one whose interaction with the child resembled normal maternal behavior, a second who interacted in a hostile way, and a third who showed a paucity of interaction.

CONCLUSION

These preliminary data suggest that smothering may reflect more than one type of abnormal maternal relationship or attitude towards children. This may have implications for treatment and prognosis.

Evidence of linkage of familial hypoalphalipoproteinemia to a novel locus on chromosome 11q23

Coronary heart disease (CHD) accounts for half of the 1 million deaths annually ascribed to cardiovascular disease and for almost all of the 1.5 million acute myocardial infarctions. Within families affected by early and apparently heritable CHD, dyslipidemias have a much higher prevalence than in the general population; 20%-30% of early familial CHD has been ascribed to primary hypoalphalipoproteinemia (low HDL-C). This study assesses the evidence for linkage of low HDL-C to chromosomal region 11q23 in 105 large Utah pedigrees ascertained with closely related clusters of early CHD and expanded on the basis of dyslipidemia. Linkage analysis was performed by use of 22 STRP markers in a 55-cM region of chromosome 11. Two-point analysis based on a general, dominant-phenotype model yielded LODs of 2.9 for full pedigrees and 3.5 for 167 four-generation split pedigrees. To define a localization region, model optimization was performed using the heterogeneity, multipoint LOD score (mpHLOD). This linkage defines a region on 11q23.3 that is approximately 10 cM distal to-and apparently distinct from-the ApoAI/CIII/AIV gene cluster and thus represents a putative novel localization for the low HDL-C phenotype.

The experiences and views of parents who care for ventilator-dependent children

Discussion in this paper is drawn from the literature examining the management of children with long-term assisted ventilation, and a study of parents' experiences and views of caring for their ventilator-dependent child at home. Difficulties in undertaking research into this group of children are highlighted. Recommendations are proposed regarding future multidisciplinary, multiagency service development in order to meet the needs of ventilator-dependent children and their families.

Activities of the Sex-lethal protein in RNA binding and protein:protein interactions

The Drosophila sex determination gene Sex-lethal (Sxl) controls its own expression, and the expression of downstream target genes such as transformer , by regulating pre-mRNA splicing and mRNA translation. Sxl codes an RNA-binding protein that consists of an N-terminus of approximately 100 amino acids, two 90 amino acid RRM domains, R1 and R2, and an 80 amino acid C-terminus. In the studies reported here we have examined the functional properties of the different Sxl protein domains in RNA binding and in protein:protein interactions. The two RRM domains are responsible for RNA binding. Specificity in the recognition of target RNAs requires both RRM domains, and proteins which consist of the single domains or duplicated domains have anomalous RNA recognition properties. Moreover, the length of the linker between domains can affect RNA recognition properties. Our results indicate that the two RRM domains mediate Sxl:Sxl protein interactions, and that these interactions probably occur both in cis and trans. We speculate that cis interactions between R1 and R2 play a role in RNA recognition by the Sxl protein, while trans interactions stabilize complex formation on target RNAs that contain two or more closely spaced binding sites. Finally, we show that the interaction of Sxl with the snRNP protein Snf is mediated by the R1 RRM domain.

Regulation of the fission yeast transcription factor Pap1 by oxidative stress: requirement for the nuclear export factor Crm1 (Exportin) and the stress-activated MAP kinase Sty1/Spc1

The fission yeast Sty1 stress-activated MAP kinase is crucial for the cellular response to a variety of stress conditions. Accordingly, sty1- cells are defective in their response to nutrient limitation, lose viability in stationary phase, and are hypersensitive to osmotic stress, oxidative stress, and UV treatment. Some of these phenotypes are caused by Sty1-dependent regulation of the Atf1 transcription factor, which controls both meiosis-specific and osmotic stress-responsive genes. However, in this report we demonstrate that the cellular response to oxidative stress and to treatment with a variety of cytotoxic agents is the result of Sty1 regulation of the Pap1 transcription factor, a bZip protein with structural and DNA binding similarities to the mammalian c-Jun protein. We show that both Sty1 and Pap1 are required for the expression of a number of genes involved in the oxidative stress response and for the expression of two genes, hba2+/bfr1+ and pmd1+, which encode energy-dependent transport proteins involved in multidrug resistance. Furthermore, we demonstrate that Pap1 is regulated by stress-dependent changes in subcellular localization. On imposition of oxidative stress, the Pap1 protein relocalizes from the cytoplasm to the nucleus in a process that is dependent on the Sty1 kinase. This relocalization is the result of regulated protein export, rather than import, and involves the Crm1 (exportin) nuclear export factor and the dcd1+/pim1+ gene that encodes an Ran nucleotide exchange factor.

The Atf1 transcription factor is a target for the Sty1 stress-activated MAP kinase pathway in fission yeast

The atf1+ gene of Schizosaccharomyces pombe encodes a bZIP transcription factor with strong homology to the mammalian factor ATF-2. ATF-2 is regulated through phosphorylation in mammalian cells by the stress-activated mitogen-activated protein (MAP) kinases SAPK/JNK and p38. We show here that the fission yeast Atf1 factor is also regulated by a stress-activated kinase, Sty1. The Sty1 kinase is stimulated by a variety of different stress conditions including osmotic and oxidative stress and heat shock. Deletion of the atf1+ gene results in many, but not all, of the phenotypes associated with loss of Sty1, including sensitivity to environmental stress and inability to undergo sexual conjugation. Furthermore, we identify a number of target genes that are induced rapidly in a manner dependent upon both the Sty1 kinase and the Atf1 transcription factor. These genes include gpd1+, which is important for the response of cells to osmotic stress, the catalase gene lambda important for cells to combat oxidative stress, and pyp2+, which encodes a tyrosine-specific MAP kinase phosphatase. Induction of Pyp2 by Atf1 is direct in that it does not require de novo protein synthesis and results in a negative feedback loop that serves to control signaling through the Sty1/Wis1 pathway. We show that Atf1 associates stably and is phosphorylated by the Sty1 kinase in vitro. Taken together, these results indicate that the interaction between AM and Sty1 is direct. These findings highlight a remarkable level of conservation in transcriptional control by stress-activated MAP kinase pathways between fission yeast and mammalian cells.

Home monitoring of infants at increased risk of sudden death

Home apnoea and cardiorespiratory monitors are commonly used in the UK, the rest of Europe and USA in infants at increased risk of 'sudden infant death'. The efficacy of apnoea and cardiorespiratory monitors remains unknown. The use of transcutaneous oxygen monitoring is presented as an alternative method of home monitoring. Recommendations are proposed regarding nursing practice and the future of home monitoring in infants at increased risk of sudden death.

A hypothesis-assessment model of categorical argument strength

According to the proposed hypothesis-assessment model, the strength of inductive categorical arguments, such as {All Robins Have Substance X therefore All Birds Have Substance X}, is determined by the same factors that affect hypothesis plausibility in the everyday social milieu. The premises of such arguments are viewed as evidence and the conclusion is viewed as a hypothesis. Specifically, the proposed model predicts that the perceived strength of general-conclusion categorical arguments will be a function of (a) the number of premises that instantiate the conclusion; (b) the scope of the conclusion; and (c) the number of accessed alternatives to the conclusion. In Experiment 1, one group rated the strength of individual arguments and another constructed superordinate hypotheses in response to the premise information alone. Most of the variance in perceived argument strength was accounted for by the proposed predictors, R = .94. Experiment 2 employed a new set of arguments and included an additional forced-choice condition in which subjects had to choose the stronger of two arguments. Again, the correlation between predictors and argument strength was high, R = .91, and, all significant forced-choice preferences except one were correctly predicted by the model. The one unpredicted preference suggests the need to include conclusion accessibility as a fourth factor. Also, on a subset of the forced-choice pairs in which no significant preference was observed, two distinct patterns of responding were detected-one predicted and the other unanticipated. Some strengths and limitations of the proposed hypothesis-assessment model are discussed in light of these results.

Sex-specific control of Sex-lethal is a conserved mechanism for sex determination in the genus Drosophila

In D. melanogaster the binary switch gene Sex-lethal (Sxl) plays a pivotal role in somatic sex determination -- when the Sxl gene is on the female pathway is followed, while the male pathway is followed when the gene is off. In the present study we have asked whether the Sxl gene is present in other species of the genus Drosophila and whether it is subject to a similar sex-specific on-off regulation. Sxl proteins were found in all of the drosophilids examined, and they display a sex-specific pattern of expression. Furthermore, characterization of the Sxl gene in the distant drosophilan relative, D. virilis, reveals that the structure and sequence organization of the gene has been well conserved and that, like melanogaster, alternative RNA processing is responsible for its sex-specific expression. Hence, this posttranscriptional on-off regulatory mechanism probably existed before the separation of the drosophilan and sophophoran subgenera and it seems likely that Sxl functions as a sex determination switch gene in most species in the Drosophila genus. Although alternative splicing appears to be responsible for the on-off regulation of the Sxl gene in D. virilis, this species is unusual in that Sxl proteins are present not only in females but also in males. The D. virilis female and male proteins appear to be identical over most of the length except for the amino-terminal approx. 25 aa which are encoded by the differentially spliced exons. In transcriptionally active polytene chromosomes, the male and female proteins bind to the same cytogenetic loci, including the sites corresponding to the D. virilis Sxl and tra genes. Hence, though the male proteins are able to interact with appropriate target pre-mRNAs, they are apparently incapable of altering the splicing pattern of these pre-mRNAs.

Negative extrathoracic pressure ventilation--evaluation of the neck seal

The effect of the neck seal used in the application of negative extra-thoracic pressure ventilation was studied using near infrared spectroscopy. Changes in cerebral blood volume (CBV) were monitored during discontinuation of negative pressure and during removal of the neck seal. CBV increased by 0.17 ml 100 ml brain-1 (95% CI +0.0875 to +0.481) when negative pressure was discontinued. Removal of the neck seal had no significant effect on CBV. It is concluded that the neck seal does not cause significant jugular venous occlusion.

Expression of chicken vinculin complements the adhesion-defective phenotype of a mutant mouse F9 embryonal carcinoma cell

A mutant cell line, derived from the mouse embryonal carcinoma cell line F9, is defective in cell-cell adhesion (compaction) and in cell-substrate adhesion. We have previously shown that neither uvomorulin (E-cadherin) nor integrins are responsible for the mutant phenotype (Calogero, A., M. Samuels, T. Darland, S. A. Edwards, R. Kemler, and E. D. Adamson. 1991. Dev. Biol. 146:499-508). Several cytoskeleton proteins were assayed and only vinculin was found to be absent in mutant (5.51) cells. A chicken vinculin expression vector was transfected into the 5.51 cells together with a neomycin-resistance vector. Clones that were adherent to the substrate were selected in medium containing G418. Two clones, 5.51Vin3 and Vin4, were analyzed by Nomarski differential interference contrast and laser confocal microscopy as well as by biochemical and molecular biological techniques. Both clones adhered well to substrates and both exhibited F-actin stress fibers with vinculin localized at stress fiber tips in focal contacts. This was in marked contrast to 5.51 parental cells, which had no stress fibers and no vinculin. The mutant and complemented F9 cell lines will be useful models for examining the complex interactions between cytoskeletal and cell adhesion proteins.