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Preliminary evidence suggests that a ketogenic diet may be effective for bipolar disorder.
Aims
To assess the impact of a ketogenic diet in bipolar disorder on clinical, metabolic and magnetic resonance spectroscopy outcomes.
Method
Euthymic individuals with bipolar disorder (N = 27) were recruited to a 6- to 8-week single-arm open pilot study of a modified ketogenic diet. Clinical, metabolic and MRS measures were assessed before and after the intervention.
Results
Of 27 recruited participants, 26 began and 20 completed the ketogenic diet. For participants completing the intervention, mean body weight fell by 4.2 kg (P < 0.001), mean body mass index fell by 1.5 kg/m2 (P < 0.001) and mean systolic blood pressure fell by 7.4 mmHg (P < 0.041). The euthymic participants had average baseline and follow-up assessments consistent with them being in the euthymic range with no statistically significant changes in Affective Lability Scale-18, Beck Depression Inventory and Young Mania Rating Scale. In participants providing reliable daily ecological momentary assessment data (n = 14), there was a positive correlation between daily ketone levels and self-rated mood (r = 0.21, P < 0.001) and energy (r = 0.19 P < 0.001), and an inverse correlation between ketone levels and both impulsivity (r = −0.30, P < 0.001) and anxiety (r = −0.19, P < 0.001). From the MRS measurements, brain glutamate plus glutamine concentration decreased by 11.6% in the anterior cingulate cortex (P = 0.025) and fell by 13.6% in the posterior cingulate cortex (P = <0.001).
Conclusions
These findings suggest that a ketogenic diet may be clinically useful in bipolar disorder, for both mental health and metabolic outcomes. Replication and randomised controlled trials are now warranted.
The presence of an intraluminal thrombus in acutely symptomatic carotid stenosis is thought to represent a high-risk lesion for short-term stroke reccurrence though evidence on natural history and treatment is lacking, leading to equipoise and much variation in practice. The objective of this study was to map these variations in practice (medical management and timing of revascularization), determine the considerations that influence clinician decision-making in this condition and gather opinions that inform the development and design of future trials in the area.
Methods:
This was a mixed-methods study using both quantitative survey methods and qualitative interview-based methods. International perspectives were gathered by distributing a case-based survey via the “Practice Current” section of Neurology: Clinical Practice and interviewing international experts using established qualitative research methods.
Results:
The presence of an intraluminal thrombus significantly increased the likelihood of using a regimen containing anticoagulation agents (p < 0.001) in acutely symptomatic carotid stenosis in the case-based survey. Themes that emerged from qualitative interview analysis were therapeutic uncertainty regarding anticoagulation, decision to reimage, revascularization choices and future trial design and anticipated challenges.
Conclusion:
Results of this study demonstrate a preference for anticoagulation and delayed revascularization after reimaging to examine for clot resolution, though much equipoise remains. While there is interest from international experts in future trials, further study is needed to understand the natural history of this condition in order to inform trial design.
Recent evidence from case reports suggests that a ketogenic diet may be effective for bipolar disorder. However, no clinical trials have been conducted to date.
Aims
To assess the recruitment and feasibility of a ketogenic diet intervention in bipolar disorder.
Method
Euthymic individuals with bipolar disorder were recruited to a 6–8 week trial of a modified ketogenic diet, and a range of clinical, economic and functional outcome measures were assessed. Study registration number: ISRCTN61613198.
Results
Of 27 recruited participants, 26 commenced and 20 completed the modified ketogenic diet for 6–8 weeks. The outcomes data-set was 95% complete for daily ketone measures, 95% complete for daily glucose measures and 95% complete for daily ecological momentary assessment of symptoms during the intervention period. Mean daily blood ketone readings were 1.3 mmol/L (s.d. = 0.77, median = 1.1) during the intervention period, and 91% of all readings indicated ketosis, suggesting a high degree of adherence to the diet. Over 91% of daily blood glucose readings were within normal range, with 9% indicating mild hypoglycaemia. Eleven minor adverse events were recorded, including fatigue, constipation, drowsiness and hunger. One serious adverse event was reported (euglycemic ketoacidosis in a participant taking SGLT2-inhibitor medication).
Conclusions
The recruitment and retention of euthymic individuals with bipolar disorder to a 6–8 week ketogenic diet intervention was feasible, with high completion rates for outcome measures. The majority of participants reached and maintained ketosis, and adverse events were generally mild and modifiable. A future randomised controlled trial is now warranted.
Whereas the beneficial effect of antiplatelet therapy for recurrent stroke prevention has been well established, uncertainties remain regarding the optimal antithrombotic regimen for recently symptomatic carotid stenosis. We sought to explore the approaches of stroke physicians to antithrombotic management of patients with symptomatic carotid stenosis.
Methods:
We employed a qualitative descriptive methodology to explore the decision-making approaches and opinions of physicians regarding antithrombotic regimens for symptomatic carotid stenosis. We conducted semi-structured interviews with a purposive sample of 22 stroke physicians (11 neurologists, 3 geriatricians, 5 interventional-neuroradiologists, and 3 neurosurgeons) from 16 centers on four continents to discuss symptomatic carotid stenosis management. We then conducted thematic analysis on the transcripts.
Results:
Important themes revealed from our analysis included limitations of existing clinical trial evidence, competing surgeon versus neurologist/internist preferences, and the choice of antiplatelet therapy while awaiting revascularization. There was a greater concern for adverse events while using multiple antiplatelet agents (e.g., dual-antiplatelet therapy (DAPT)) in patients undergoing carotid endarterectomy compared to carotid artery stenting. Regional variations included more frequent use of single antiplatelet agents among European participants. Areas of uncertainty included antithrombotic management if already on an antiplatelet agent, implications of nonstenotic features of carotid disease, the role of newer antiplatelet agents or anticoagulants, platelet aggregation testing, and timing of DAPT.
Conclusion:
Our qualitative findings can help physicians critically examine the rationale underlying their own antithrombotic approaches to symptomatic carotid stenosis. Future clinical trials may wish to accommodate identified variations in practice patterns and areas of uncertainty to better inform clinical practice.
The Repugnant Conclusion is an implication of some approaches to population ethics. It states, in Derek Parfit's original formulation,
For any possible population of at least ten billion people, all with a very high quality of life, there must be some much larger imaginable population whose existence, if other things are equal, would be better, even though its members have lives that are barely worth living. (Parfit 1984: 388)
Ecosystem modeling, a pillar of the systems ecology paradigm (SEP), addresses questions such as, how much carbon and nitrogen are cycled within ecological sites, landscapes, or indeed the earth system? Or how are human activities modifying these flows? Modeling, when coupled with field and laboratory studies, represents the essence of the SEP in that they embody accumulated knowledge and generate hypotheses to test understanding of ecosystem processes and behavior. Initially, ecosystem models were primarily used to improve our understanding about how biophysical aspects of ecosystems operate. However, current ecosystem models are widely used to make accurate predictions about how large-scale phenomena such as climate change and management practices impact ecosystem dynamics and assess potential effects of these changes on economic activity and policy making. In sum, ecosystem models embedded in the SEP remain our best mechanism to integrate diverse types of knowledge regarding how the earth system functions and to make quantitative predictions that can be confronted with observations of reality. Modeling efforts discussed are the Century ecosystem model, DayCent ecosystem model, Grassland Ecosystem Model ELM, food web models, Savanna model, agent-based and coupled systems modeling, and Bayesian modeling.
To investigate an outbreak of Burkholderia cepacia complex and describe the measures that revealed the source.
SETTING
A 629-bed, tertiary-care, pediatric hospital in Houston, Texas.
PATIENTS
Pediatric patients without cystic fibrosis (CF) hospitalized in the pediatric and cardiovascular intensive care units.
METHODS
We investigated an outbreak of B. cepacia complex from February through July 2016. Isolates were evaluated for molecular relatedness with repetitive extragenic palindromic polymerase chain reaction (rep-PCR); specific species identification and genotyping were performed at an independent laboratory. The investigation included a detailed review of all cases, direct observation of clinical practices, and respiratory surveillance cultures. Environmental and product cultures were performed at an accredited reference environmental microbiology laboratory.
RESULTS
Overall, 18 respiratory tract cultures, 5 blood cultures, 4 urine cultures, and 3 stool cultures were positive in 24 patients. Among the 24 patients, 17 had symptomatic infections and 7 were colonized. The median age of the patients was 22.5 months (range, 2–148 months). Rep-PCR typing showed that 21 of 24 cases represented the same strain, which was identified as a novel species within the B. cepacia complex. Product cultures of liquid docusate were positive with an identical strain of B. cepacia complex. Local and state health departments, as well as the CDC and FDA, were notified, prompting a multistate investigation.
CONCLUSIONS
Our investigation revealed an outbreak of a unique strain of B. cepacia complex isolated in clinical specimens from non-CF pediatric patients and from liquid docusate. This resulted in a national alert and voluntary recall by the manufacturer.
Femtosecond laser direct writing (FsLDW) in transparent materials is a laser-based precise three-dimensional (3D) micro/nanofabrication method that has shown great potential for applications. The advantages of FsLDW originate in the nonlinear nature of absorption in the multiphoton absorption process. Over the past few years, transparent material micro/nanofabrication using FsLDW has seen several developments in materials and applications. Specifically, two-photon polymerization has been widely used as a precision direct-writing process for fabrication of polymeric 3D micro/nanostructures; internal/surface ablation of polymer 3D structures based on multiphoton absorption has been demonstrated and developed as a promising subtractive manufacturing technique; and femtosecond laser multiphoton modification in glass has been intensively studied for refractive-index change and generation of nanogratings and microvoids. This article describes the latest research on FsLDW in polymers and glasses with specific applications for large-dimension fabrication, microelectromechanical systems, microphotonics, and microfluidics.
The cat flea, Ctenocephalides felis, is a major pest species on companion animals thus of significant importance to the animal health industry. The aim of this study was to develop sampling and storage protocols and identify stable reference genes for gene expression studies to fully utilize the growing body of molecular knowledge of C. felis. RNA integrity was assessed in adult and larvae samples, which were either pierced or not pierced and stored in RNAlater at ambient temperature. RNA quality was maintained best in pierced samples, with negligible degradation evident after 10 days. RNA quality from non-pierced samples was poor within 3 days. Ten candidate reference genes were evaluated for their stability across four group comparisons (developmental stages, genders, feeding statuses and insecticide-treatment statuses). Glyceraldehyde 3 phosphate dehydrogenase (GAPDH), 60S ribosomal protein L19 (RPL19) and elongation factor-1α (Ef) were ranked highly in all stability comparisons, thus are recommended as reference genes under similar conditions. Employing just two of these three stable reference genes was sufficient for accurate normalization. Our results make a significant contribution to the future of gene expression studies in C. felis, describing validated sample preparation procedures and reference genes for use in this common pest.
While the summit of the Antarctic Plateau has long been expected to harbor the best ground-based sites for terahertz (THz) frequency astronomical investigations, it is only recently that direct observations of exceptional THz atmospheric transmission and stability have been obtained. These observations, in combination with recent technological advancements in astronomical instrumentation and autonomous field platforms, make the recognition and realization of terahertz observatories on the high plateau feasible and timely. Here, we will explore the context of terahertz astronomy in the era of Herschel, and the crucial role that observatories on the Antarctic Plateau can play. We explore the important scientific questions to which observations from this unique environment may be most productively applied. We examine the importance and complementarity of Antarctic THz astronomy in the light of contemporary facilities such as ALMA, CCAT, SOFIA and (U)LDB ballooning. Finally, building from the roots of THz facilities in Antarctica to present efforts, we broadly highlight future facilities that will exploit the unique advantages of the Polar Plateau and provide a meaningful, lasting astrophysical legacy.
The spectral reflectance of phytophagous insects' host plants is usually quantified between 300–350 nm (ultraviolet, UV) and 700 nm (farred to infrared), and the shape and magnitude of the distribution of reflected light determine the hue, saturation, and intensity perceived by insects (Moericke 1969). Host perception also depends on the distribution of environmental light (Endler 1993) and on the constraints of the insects' visual system, which is usually described as dichromatic, with one type of photoreceptor responding maximally to blue light (λmax = ca. 400–470 nm) and another to green light (λmax = ca. 500–530 nm). UV receptors also appear to be common, if not ubiquitous (Briscoe and Chittka 2001; Mazza et al. 2002). Several phytophagous insects have been shown to use visual cues, including UV reflectance, to locate and (or) discriminate among plants (Prokopy and Owens 1983).
To systematically review studies reporting the effectiveness of various models of follow-up in primary care on a range of outcomes (physical, psychological, social functioning, or quality of life) for survivors of stroke and their caregivers.
Background
Stroke is a major cause of disability globally. Current UK policy calls for a primary care-based review of healthcare and social-care needs at six weeks and six months after hospital discharge and then annually.
Methods
Trials meeting the pre-defined inclusion criteria were identified by the systematic searching of electronic databases. Data were extracted by two independent researchers. Studies were rated using the McMaster University Quality Assessment Tool.
Findings
Nine randomised controlled trials that met the inclusion criteria were identified. These studies included interventions using stroke support workers, care coordinators or case managers. The methodological quality of the studies was variable, and models of care demonstrated inconsistent working relationships with general practitioners. Patients and caregivers receiving formal primary care-based follow-up did not show any gains in physical function, mood, or quality of life when compared with those who did not. Patients and caregivers receiving follow-up were generally more satisfied with some aspects of communication, and had a greater knowledge of stroke.
Conclusions
The limited quality of these studies and the lack of a sound theoretical basis for the development of interventions together highlight the urgent need for high-quality research studies in this area.
Edited by
Alex S. Evers, Washington University School of Medicine, St Louis,Mervyn Maze, University of California, San Francisco,Evan D. Kharasch, Washington University School of Medicine, St Louis
To explore the experiences of people with advanced cancer and/or their caregivers accessing out-of-hours care.
Background
The organisation and delivery of out-of-hours in the United Kingdom has undergone major reforms over the past three decades culminating in the new General Medical Service contract in 2004. There are concerns around continuity of care for patients with complex needs under the new arrangements.
Design
A qualitative interview study was undertaken recruiting patients from two primary care trusts in Southwest England. Semi-structured interviews were conducted with 28 people with advanced cancer and/or their caregivers who had recently requested out-of-hours care. Interviews were recorded, transcribed and analysed thematically.
Findings
Two main themes were identified including the legitimacy of seeking help and continuities of care. Most participants were reluctant to seek help, finding it difficult to decide whether their needs were sufficient to contact services. The degree to which services legitimised participants’ requests mediated their experiences. Distress arose when services were dismissive of their needs, whereas respondents were appreciative of clinicians who provided them with reassurance. Participants reported a lack of relational and informational continuity of care. Consulting with an unfamiliar clinician out-of-hours raised doubts in some participants’ minds about the quality of care. Some participants recounted episodes in which there were problems with pain management. While the themes suggest that the delivery of out-of-hours care as a whole was not always perfect, around-the-clock access to professional sources of support and reassurance was highly valued. However, the transfer of information to out-of-hours providers remains a key challenge; participants did not understand why out-of-hours providers could not access more information on their medical histories given the level of computerisation within the National Health Service. The findings highlight the need to improve continuity between in-hours and out-of-hours services for patients with complex needs.