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1.
Cell ; 187(8): 1834-1852.e19, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38569543

ABSTRACT

Accumulating evidence suggests that cardiovascular disease (CVD) is associated with an altered gut microbiome. Our understanding of the underlying mechanisms has been hindered by lack of matched multi-omic data with diagnostic biomarkers. To comprehensively profile gut microbiome contributions to CVD, we generated stool metagenomics and metabolomics from 1,429 Framingham Heart Study participants. We identified blood lipids and cardiovascular health measurements associated with microbiome and metabolome composition. Integrated analysis revealed microbial pathways implicated in CVD, including flavonoid, γ-butyrobetaine, and cholesterol metabolism. Species from the Oscillibacter genus were associated with decreased fecal and plasma cholesterol levels. Using functional prediction and in vitro characterization of multiple representative human gut Oscillibacter isolates, we uncovered conserved cholesterol-metabolizing capabilities, including glycosylation and dehydrogenation. These findings suggest that cholesterol metabolism is a broad property of phylogenetically diverse Oscillibacter spp., with potential benefits for lipid homeostasis and cardiovascular health.


Subject(s)
Bacteria , Cardiovascular Diseases , Cholesterol , Gastrointestinal Microbiome , Humans , Bacteria/metabolism , Cardiovascular Diseases/metabolism , Cholesterol/analysis , Cholesterol/blood , Cholesterol/metabolism , Feces/chemistry , Longitudinal Studies , Metabolome , Metabolomics , RNA, Ribosomal, 16S/metabolism
2.
Cell ; 179(3): 750-771.e22, 2019 10 17.
Article in English | MEDLINE | ID: mdl-31626773

ABSTRACT

Tissue-specific regulatory regions harbor substantial genetic risk for disease. Because brain development is a critical epoch for neuropsychiatric disease susceptibility, we characterized the genetic control of the transcriptome in 201 mid-gestational human brains, identifying 7,962 expression quantitative trait loci (eQTL) and 4,635 spliceQTL (sQTL), including several thousand prenatal-specific regulatory regions. We show that significant genetic liability for neuropsychiatric disease lies within prenatal eQTL and sQTL. Integration of eQTL and sQTL with genome-wide association studies (GWAS) via transcriptome-wide association identified dozens of novel candidate risk genes, highlighting shared and stage-specific mechanisms in schizophrenia (SCZ). Gene network analysis revealed that SCZ and autism spectrum disorder (ASD) affect distinct developmental gene co-expression modules. Yet, in each disorder, common and rare genetic variation converges within modules, which in ASD implicates superficial cortical neurons. More broadly, these data, available as a web browser and our analyses, demonstrate the genetic mechanisms by which developmental events have a widespread influence on adult anatomical and behavioral phenotypes.


Subject(s)
Autism Spectrum Disorder/genetics , Quantitative Trait Loci/genetics , Schizophrenia/genetics , Transcriptome/genetics , Autism Spectrum Disorder/metabolism , Autism Spectrum Disorder/pathology , Brain/growth & development , Brain/metabolism , Female , Fetus/metabolism , Gene Expression Regulation, Developmental , Genetic Predisposition to Disease , Genome-Wide Association Study , Gestational Age , Humans , Male , Neurons/metabolism , Polymorphism, Single Nucleotide/genetics , RNA Splicing/genetics , Schizophrenia/metabolism , Schizophrenia/pathology
5.
Emerg Infect Dis ; 29(4): 761-770, 2023 04.
Article in English | MEDLINE | ID: mdl-36918377

ABSTRACT

SARS-CoV-2 infections among vaccinated nursing home residents increased after the Omicron variant emerged. Data on booster dose effectiveness in this population are limited. During July 2021-March 2022, nursing home outbreaks in 11 US jurisdictions involving >3 infections within 14 days among residents who had received at least the primary COVID-19 vaccine(s) were monitored. Among 2,188 nursing homes, 1,247 outbreaks were reported in the periods of Delta (n = 356, 29%), mixed Delta/Omicron (n = 354, 28%), and Omicron (n = 536, 43%) predominance. During the Omicron-predominant period, the risk for infection within 14 days of an outbreak start was lower among boosted residents than among residents who had received the primary vaccine series alone (risk ratio [RR] 0.25, 95% CI 0.19-0.33). Once infected, boosted residents were at lower risk for all-cause hospitalization (RR 0.48, 95% CI 0.40-0.49) and death (RR 0.45, 95% CI 0.34-0.59) than primary vaccine-only residents.


Subject(s)
COVID-19 , United States/epidemiology , Humans , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , SARS-CoV-2 , Nursing Homes , Disease Outbreaks
6.
Phys Rev Lett ; 130(21): 216802, 2023 May 26.
Article in English | MEDLINE | ID: mdl-37295101

ABSTRACT

A critical end point above which an isotropic phase continuously evolves into a polar (ferroelectric) nematic phase with an increasing electric field is found in a ferroelectric nematic liquid crystalline material. The critical end point is approximately 30 K above the zero-field transition temperature from the isotropic to nematic phase and at an electric field of the order of 10 V/µm. Such systems are interesting from the application point of view because a strong birefringence can be induced in a broad temperature range in an optically isotropic phase.

7.
Chemphyschem ; 24(6): e202200807, 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36422888

ABSTRACT

Non-symmetric lactate-based chiral liquid crystal dimers containing an odd-membered spacer are shown to exhibit a chiral twist-bend nematic phase which is stable on cooling to room temperature. A comparison of racemic and optically pure materials reveals that the pitch length in the N*TB phase is not influenced by molecular chirality, whereas the nematic-twist-bend nematic transition temperature is increased.

8.
Chemphyschem ; 24(6): e202300105, 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36916801

ABSTRACT

The front cover artwork is provided by Dr Rebecca Walker of the Liquid Crystals Group at the University of Aberdeen. The image is a cartoon depiction of the formation of the heliconical chiral twist-bend nematic phase (N*TB ) from its constituent bent molecules. The presence of a single enantiomer of the chiral, lactate-based liquid crystal dimers biases the formation of helices with only one handedness, unlike in the conventional NTB phase, observed for achiral molecules, for which the left- and right-handed helices are doubly degenerate. Read the full text of the Research Article at 10.1002/cphc.202200807.

9.
FASEB J ; 35(10): e21865, 2021 10.
Article in English | MEDLINE | ID: mdl-34486178

ABSTRACT

Autosomal dominant polycystic kidney disease is a common inherited renal disorder that results from mutations in either PKD1 or PKD2, encoding polycystin-1 (PC1) and polycystin-2 (PC2), respectively. Downregulation or overexpression of PKD1 or PKD2 in mouse models results in renal cyst formation, suggesting that the quantity of PC1 and PC2 needs to be maintained within a tight functional window to prevent cystogenesis. Here we show that enhanced PC2 expression is a common feature of PKD1 mutant tissues, in part due to an increase in Pkd2 mRNA. However, our data also suggest that more effective protein folding contributes to the augmented levels of PC2. We demonstrate that the unfolded protein response is activated in Pkd1 knockout kidneys and in Pkd1 mutant cells and that this is coupled with increased levels of GRP94, an endoplasmic reticulum protein that is a member of the HSP90 family of chaperones. GRP94 was found to physically interact with PC2 and depletion or chemical inhibition of GRP94 led to a decrease in PC2, suggesting that GRP94 serves as its chaperone. Moreover, GRP94 is acetylated and binds to histone deacetylase 6 (HDAC6), a known deacetylase and activator of HSP90 proteins. Inhibition of HDAC6 decreased PC2 suggesting that HDAC6 and GRP94 work together to regulate PC2 levels. Lastly, we showed that inhibition of GRP94 prevents cAMP-induced cyst formation in vitro. Taken together our data uncovered a novel HDAC6-GRP94-related axis that likely participates in maintaining elevated PC2 levels in Pkd1 mutant cells.


Subject(s)
Cysts/pathology , Endoplasmic Reticulum/metabolism , Kidney Diseases/pathology , Membrane Glycoproteins/metabolism , PAX8 Transcription Factor/physiology , TRPP Cation Channels/physiology , Animals , Calcium/metabolism , Cysts/etiology , Cysts/metabolism , Kidney Diseases/etiology , Kidney Diseases/metabolism , Membrane Glycoproteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Unfolded Protein Response
10.
Soft Matter ; 18(25): 4679-4688, 2022 Jun 29.
Article in English | MEDLINE | ID: mdl-35678154

ABSTRACT

The synthesis and characterisation of the 1-(4-cyanobiphenyl-4'-yl)-10-(4-alkylanilinebenzylidene-4'-oxy)decanes (CB10O·m) are reported. This series shows a rich liquid crystal polymorphism including twist-bend nematic and smectic phases. All the homologues reported exhibit an enantiotropic conventional nematic phase. For the homologues with m ≤ 10, the local packing in the nematic phases and the layer spacing in the smectic phases indicates an intercalated arrangement of the molecules. An intercalated smectic CA phase is observed if m/11 ≈ 0.5. Either side of this condition, the twist-bend nematic phase is observed, a novel pattern of behaviour for a series on increasing a terminal chain length. For longer chain lengths, m = 12, 14, 16 and 18, two twist-bend smectic C (SmCTB) phases are observed, and the packing of the molecules is now of a bilayer-type. The higher temperature variant is termed SmCTB-SH in which SH (single helix) refers to the presence of a short, distorted clock-type helix. In the lower temperature SmCTB-DH phase, an additional longer helix is superimposed on the short one, and DH denotes double helix.

11.
Wilderness Environ Med ; 33(4): 454-459, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36241486

ABSTRACT

We describe the evolution of the nonprofit Nepal Ambulance Service (NAS) in a narrative of its 10-y history, presenting geographical, social, cultural, and financial considerations that permeated the development of NAS. We gathered narrative information from the NAS leadership and partners to detail key organizational considerations regarding the implementation and maintenance of the prehospital system in Nepal. We describe the response of NAS to the 2015 earthquake and summarize transport data for 6 mo before and 6 mo after the event. The data collected included the date and time of calls received, time to ambulance dispatch, on-scene time, time to arrival at the hospital, time until the ambulance crew was back in service, patient age and sex, chief complaints, and work shift time of the ambulance crew. To characterize the time to response and transport after the 2015 earthquake, we present the means and standard deviations of the time intervals. There was an overall increase in calls and, specifically, trauma-related calls after the 2015 earthquake. The time from a call placed to dispatch was stable, approximately 2 min, throughout the period, whereas the time from dispatch to the scene and arrival at the scene varied widely. We discuss the response to coronavirus disease 2019 (COVID-19). The NAS provided care to 1230 patients with COVID-19. The descriptive data show how well NAS responded to a major national disaster and the recent pandemic.


Subject(s)
COVID-19 , Emergency Medical Services , Humans , Ambulances , COVID-19/epidemiology , Nepal
12.
Chemphyschem ; 22(5): 461-470, 2021 Mar 03.
Article in English | MEDLINE | ID: mdl-33369044

ABSTRACT

A selection of pyrene-based liquid crystal dimers have been prepared, containing either methylene-ether or diether linked spacers of varying length and parity. All the diether linked materials, CBOnO.Py (n=5, 6, 11, 12), exhibit conventional nematic and smectic A phases, with the exception of CBO11O.Py which is exclusively nematic. The methylene-ether linked dimer, CBnO.Py, with an even-membered spacer (n=5) was solely nematogenic, but odd-members (n=6, 8, 10) exhibited both nematic and twist-bend nematic phases. Replacement of the cyanobiphenyl fragment by cyanoterphenyl giving CT6O.Py, gave elevated melting and nematic-isotropic transition temperatures, and SmA and SmCA phases were observed on cooling the nematic phase. Intermolecular face-to-face associations of the pyrene moieties drive glass formation, and all these materials have a glass transition temperature at or above room temperature. The stability of the glassy twist-bend nematic phase allowed for its study using AFM, and the helical pitch length, PTB , was measured as 6.3 and 6.7 nm for CB6O.Py and CB8O.Py, respectively. These values are comparable to the shortest pitch of a twist-bend nematic phase measured to date.

13.
EMBO Rep ; 20(11): e48336, 2019 11 05.
Article in English | MEDLINE | ID: mdl-31441214

ABSTRACT

Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in PKD1 or PKD2 gene, encoding the polycystic kidney disease protein polycystin-1 and the transient receptor potential channel polycystin-2 (also known as TRPP2), respectively. Polycystin-1 and polycystin-2 form a receptor-ion channel complex located in primary cilia. The function of this complex, especially the role of polycystin-1, is largely unknown due to the lack of a reliable functional assay. In this study, we dissect the role of polycystin-1 by directly recording currents mediated by a gain-of-function (GOF) polycystin-1/polycystin-2 channel. Our data show that this channel has distinct properties from that of the homomeric polycystin-2 channel. The polycystin-1 subunit directly contributes to the channel pore, and its eleven transmembrane domains are sufficient for its channel function. We also show that the cleavage of polycystin-1 at the N-terminal G protein-coupled receptor proteolysis site is not required for the activity of the GOF polycystin-1/polycystin-2 channel. These results demonstrate the ion channel function of polycystin-1 in the polycystin-1/polycystin-2 complex, enriching our understanding of this channel and its role in ADPKD.


Subject(s)
Ion Channels/metabolism , Protein Multimerization , TRPP Cation Channels/metabolism , Animals , Calcium/metabolism , Electrophysiological Phenomena , Ion Channel Gating , Ion Channels/chemistry , Ion Channels/genetics , Ion Transport , Kinetics , Models, Molecular , Mutation , Oocytes/metabolism , Permeability , Protein Conformation , Protein Transport , TRPP Cation Channels/chemistry , TRPP Cation Channels/genetics , Xenopus
14.
Clin Trials ; 18(4): 477-487, 2021 08.
Article in English | MEDLINE | ID: mdl-33938244

ABSTRACT

BACKGROUND/AIMS: Financial compensation for research participation is a major focus of ethical concern regarding human subject recruitment. Phase I trials are sometimes considered to be a lucrative source of income for healthy volunteers, encouraging some people to become "professional guinea pigs." Yet, little is known about how much these clinical trials actually pay and how much healthy volunteers earn from them. METHODS: As part of a mixed-methods, longitudinal study of healthy volunteers, we required participants to complete clinical trial diaries, or surveys that captured detailed information about screening and enrollment in Phase I trials. Over a 3-year period, participants provided information online or via telephone about each clinical trial for which they screened (e.g. the clinic name, the study's therapeutic area, the length of the trial, the number of nights spent in the clinic, and the study compensation), and whether they qualified for trial inclusion. Clinical trial diaries generated data about whether participants continued to screen for and enroll in clinical trials and how much money they earned from their participation. RESULTS: 131 participants routinely completed clinical trial diaries or confirmed that they had not screened for any new clinical trials. Together, these participants screened for 1001 clinical trials at 73 research facilities during a 3-year period. Overall, the median clinical trial compensation was US$3070 (range = US$150-US$13,000). Participants seeking new healthy volunteer trials tended to screen for three studies per year, participate in one or two studies, and earn roughly US$4000 annually. Participants who were unemployed earned the most income from clinical trials compared to those with full-time or part-time jobs, and those individuals whom we label "occupational" participants because of their persistent pursuit of clinical trials earned more than people who screened occasionally. Notably, the median annual trial compensation was well below US$10,000 for all employment groups, and most occupational healthy volunteers also earned less than US$10,000 each year. The 10% of participants who earned the most had a median annual income of US$18,885 from clinical trials, and there was significant volatility in these individuals' earnings from year to year. CONCLUSION: Despite the perception that Phase I enrollment can generate significant earnings, it was exceedingly rare for anyone in this study to make more than US$20,000 in a single year, and unusual to earn even between US$10,000 and US$20,000. From an ethics perspective, individual trials might appear to unduly induce enrollment by offering significant sums of money, but given our findings, the larger problem for low-income participants may be the unrealistic perception that clinical trials alone could be a way of earning a living.


Subject(s)
Clinical Trials, Phase I as Topic/economics , Income , Patient Participation/economics , Research Subjects , Healthy Volunteers , Humans , Longitudinal Studies , Surveys and Questionnaires
15.
Value Health ; 23(1): 104-113, 2020 01.
Article in English | MEDLINE | ID: mdl-31952665

ABSTRACT

BACKGROUND: In diseases where there is a large subjective component, such as celiac disease (CD), patient reported-outcomes (PRO) endpoints are highly relevant. However, there is a gap in knowledge about which PRO endpoints and instruments should be used for clinical trials for treatment of celiac disease. OBJECTIVES: To identify patient-centered symptom, impact, and health-related quality of life (HRQoL) concepts in CD and relevant PRO instruments, and to gather expert input on concepts and instruments to inform selection of PRO endpoints for use in clinical trials of new CD treatments. METHODS: A targeted literature review was conducted to identify symptom, impact, and HRQoL concepts, including those captured in PROs further reviewed against U.S. Food and Drug Administration standards for development and validation as endpoints. US and European clinicians, payers, and a patient advocate (n = 21) were interviewed to assess the identified concepts' relative importance in measuring treatment benefit and to gauge the value of potential PROs as endpoints for market access/reimbursement. RESULTS: Thirty-four published studies were identified: 27 elucidated patient-centered concepts and 7 detailed the development or validation of PRO instruments. The Celiac Disease Symptom Diary and Celiac Disease Patient Reported Outcome instrument were deemed most appropriate for use as endpoints; however, each had limitations related to conceptual coverage, evidence for measurement properties, and feasibility for use in clinical trials. Experts reported gastrointestinal symptoms as most important to treat, with extra-intestinal symptoms burdensome from the patient perspective as well. Payers emphasized measuring both frequency and severity of symptoms and targeting patients nonresponsive to the gluten-free diet for treatment. CONCLUSIONS: With emerging treatment options for CD, further work is needed to operationalize PRO symptom endpoints that are meaningful to patients, valued by payers, and acceptable to regulators in demonstrating efficacy.


Subject(s)
Celiac Disease/therapy , Diet, Gluten-Free , Patient Reported Outcome Measures , Celiac Disease/diagnosis , Celiac Disease/economics , Cost of Illness , Cost-Benefit Analysis , Diet, Gluten-Free/adverse effects , Diet, Gluten-Free/economics , Health Care Costs , Health Status , Humans , Quality of Life , Severity of Illness Index , Stakeholder Participation , Treatment Outcome
16.
Sensors (Basel) ; 20(21)2020 Oct 25.
Article in English | MEDLINE | ID: mdl-33113815

ABSTRACT

Unmanned aerial vehicles (UAV) are increasingly becoming a popular tool in the observation and study of marine mammals. However, the potential capabilities of these vehicles regarding autonomous operations are not being fully exploited for passive underwater acoustic monitoring in marine mammal research. This article presents results from the development of a UAV system equipped with an underwater acoustic recorder aimed at assisting with the monitoring of harbour porpoises in Special Areas of Conservation in the United Kingdom. The UAV is capable of autonomous navigation, persistent landing, take-off and automatic data acquisition at specified waypoints. The system architecture that enables autonomous UAV flight including waypoint planning and control is described. A bespoke lightweight underwater acoustic recorder (named the PorpDAQ) capable of transmitting the results of fast Fourier transforms (FFT) applied to incoming signals from a hydrophone was also designed. The system's operation is successfully validated with a combination of outdoor experiments and indoor simulations demonstrating different UAVs capable of autonomously navigating and landing at specific waypoints while recording data in an indoor tank. Results from the recorder suggest that lightweight, relatively low-cost systems can be used in place of heavier more expensive alternatives.

17.
J Med Philos ; 45(4-5): 521-539, 2020 07 29.
Article in English | MEDLINE | ID: mdl-32619222

ABSTRACT

This essay explores three issues in respect for autonomy that pose unfinished business for the concept. By this, I mean that the dialogue over them is ongoing and essentially unresolved. These are: (1) whether we ought to respect persons or their autonomous choices; (2) the role of relational autonomy; and (3) whether nonhuman animals can be autonomous. In attending to this particular set of unfinished business, I highlight some critical moral work left aside by the concept of respect for autonomy as understood in Beauchamp and Childress' Principles of Biomedical Ethics. Specifically, while significant pragmatic traction is gained by the authors' focus on autonomous choice, carving such a focus out from the broader questions of moral respect and the autonomy of the person leaves aside a number of questions that we might have thought a view about respect for autonomy in biomedicine ought to answer. These include: How should physicians respond when autonomous patients make decisions that appear nonautonomous? What is the impact of the view that autonomy is "relational" for cross-cultural differences in how autonomy is respected? If chimpanzees (and by extension young children) can be autonomous, what does that mean for how they should be treated?


Subject(s)
Bioethics , Decision Making , Personal Autonomy , Animals , Cultural Characteristics , Humans , Interpersonal Relations , Morals , Pan troglodytes , Relational Autonomy , Respect
18.
Chemistry ; 25(58): 13329-13335, 2019 Oct 17.
Article in English | MEDLINE | ID: mdl-31322779

ABSTRACT

The twist-bend nematic, NTB , phase has been observed for chiral materials in which chirality is introduced through a branched 2-methylbutyl terminal tail. The chiral twist-bend nematic phase, N*TB , is completely miscible with the NTB phase of the standard achiral material, CB6OCB. The N*TB phase exhibits optical textures with lower birefringence than those observed for the achiral NTB phase, suggesting an additional mechanism of averaging molecular orientations. The N*-N*TB transition temperatures for the chiral materials are higher than the NTB -N transition temperatures seen for the corresponding racemic materials. This suggests the double degeneracy of helical twist sense in the N T B * phase is removed by the intrinsic molecular chirality. A square lattice pattern is observed in the N* phase over a temperature range of several degrees above the N*TB -N phase transition, which may be attributed to a non-monotonic dependence of the bend elastic constant.

19.
Soft Matter ; 15(15): 3188-3197, 2019 Apr 10.
Article in English | MEDLINE | ID: mdl-30892369

ABSTRACT

The syntheses and characterisation of the first ten homologues of the 1-(4-cyanobiphenyl-4'-yl)-6-(4-alkylanilinebenzylidene-4'-oxy)hexanes (CB6O.m) are reported. All ten members of the series exhibit an enantiotropic nematic, N, phase, and a monotropic twist-bend nematic, NTB, phase. Only CB6O.10 shows a smectic phase. The assignment of both nematic phases was confirmed using X-ray diffraction. For short chain lengths (m = 1-6) the local packing in both nematic phases is an intercalated arrangement, for intermediate chain lengths a frustrated local structure is seen and for the longest chain length, a bilayer arrangement is observed. This change in the local structure on increasing m has no apparent effect on the stability of either nematic phase, and TNTBN and TNI show a regular dependence on m. Specifically, TNTBN and TNI decrease on increasing m and superimposed upon this is a weak odd-even effect in which the odd members show the higher values. TNI decreases more rapidly than TNTBN on increasing m such that the ratio TNTBN/TNI increases. The lower temperature liquid crystal phase shown by 1-(4-cyanobiphenyl-4'-yloxy)-5-(4-butylanilinebenzylidene-4'-oxy)pentane (CBO5O.4) is reassigned as a twist-bend nematic phase. The transitional properties of the CB6O.m, CB6O.Om and CBO5O.m series are compared.

20.
Curr Allergy Asthma Rep ; 19(7): 33, 2019 06 03.
Article in English | MEDLINE | ID: mdl-31161313

ABSTRACT

PURPOSE OF REVIEW: To examine the relationship between vitamin D and otitis media. RECENT FINDINGS: Vitamin D deficiency has been associated with several respiratory diseases, including otitis media. Vitamin D supplementation may reduce the risk of otitis media. This relationship may be explained by vitamin D supporting the immune system by upregulating antimicrobial peptides which are effective against otopathogens and biofilm formation, supporting a less inflammatory immune response, or promoting beneficial commensal bacteria. This review will explore risk factors of both otitis media and vitamin D deficiency, the evidence of vitamin D being beneficial for various forms of otitis media, and possible mechanisms of action.


Subject(s)
Otitis Media/etiology , Dietary Supplements , Humans , Vitamin D/pharmacology , Vitamin D Deficiency/complications , Vitamins/pharmacology
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