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2.
mSphere ; 8(1): e0026322, 2023 02 21.
Article in English | MEDLINE | ID: mdl-36598226

ABSTRACT

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus is thought to have originated in wild bats from Asia, and as the resulting pandemic continues into its third year, concerns have been raised that the virus will expand its host range and infect North American wildlife species, including bats. Mexican free-tailed bats (Tadarida brasiliensis) live in large colonies in the southern United States, often in urban areas and, as such, could be exposed to the virus from infected humans. We experimentally challenged wild T. brasiliensis with SARS-CoV-2 to determine the susceptibility, reservoir potential, and population impacts of infection in this species. Of 10 bats oronasally inoculated with SARS-CoV-2, 5 became infected and orally excreted moderate amounts of virus for up to 18 days postinoculation. These five subjects all seroconverted and cleared the virus before the end of the study with no obvious clinical signs of disease. We additionally found no evidence of viral transmission to uninoculated subjects. These results indicate that while T. brasiliensis are susceptible to SARS-CoV-2 infection, infection of wild populations of T. brasiliensis would not likely cause mortality. However, the transmission of SARS-CoV-2 from T. brasiliensis to or from humans, or to other animal species, is a possibility requiring further investigation to better define. IMPORTANCE As the COVID-19 pandemic has continued for 3+ years, there has been increasing concern that the SARS-CoV-2 virus will enter wildlife populations and potentially create new reservoirs where the virus could adapt to a new host and create variants. This is particularly possible with species that reside in man-made structures, in proximity to infected human populations. Mexican free-tailed bats (Tadarida brasiliensis) live in large colonies, often in urban settings and, thus, can be exposed by infected humans and potentially transmit the virus to new hosts. We experimentally challenged T. brasiliensis with SARS-CoV-2 and revealed that they are susceptible to the virus and excrete moderate amounts for up to 18 days postinoculation. This is important information for wildlife biologists, wildlife rehabilitation workers, and the general public that may contact these animals.


Subject(s)
COVID-19 , Chiroptera , Animals , Humans , SARS-CoV-2 , Pandemics , Animals, Wild
3.
Mil Med ; 188(3-4): e718-e724, 2023 03 20.
Article in English | MEDLINE | ID: mdl-34411239

ABSTRACT

INTRODUCTION: In order to better treat obstructive sleep apnea (OSA) in a more efficient and cost-effective way, a joint program between dental clinics and the sleep medicine clinic was piloted at Fort Hood, Texas. Obstructive sleep apnea negatively affects soldier readiness and deployability, leading to the need to establish a successful and proven workflow to treat these patients with oral appliance therapy (OAT). MATERIALS AND METHODS: We performed a retrospective review of a de-identified data set which included 288 patients from July 2016 to July 2020. Projected cost data were obtained from routinely collected sleep clinic positive airway pressure (PAP) data. Data were analyzed to determine treatment success and potential cost savings using OAT versus continuous positive airway pressure (CPAP). Patient workflow including successes and challenges with the program is summarized. RESULTS: About 85.5% of patients met criteria for successful control of their OSA using OAT as treatment. Five patients did not tolerate OAT and switched back to CPAP. A higher (less severe) O2 nadir on diagnostic polysomnography is moderately correlated with OAT success. Diagnostic Apnea-Hypopnea Index was inversely and weakly correlated with success. Two of the major challenges noted in the program were (1) loss of follow-up and (2) the length of time from oral appliance referral to fitting the oral appliance. If this program was successfully implemented at other Defense Health Agency (DHA) medical treatment facility (MTF) markets nationwide, a potential cost savings of over $500,000/year/MTF could be achieved. CONCLUSIONS: Oral appliance therapy has the potential to increase both readiness and deployability for active duty soldiers. Using baseline O2 nadir can help predict success with OAT patients, determining which patients will benefit from this joint program between the dental and medical sleep clinics. Future studies can aim to establish an evidence-based pathway for clinic testing and follow-up. If this patient workflow is implemented properly, there can be significant cost savings army-wide. This all helps The United States Medical Command (MEDCOM) align with the DHA's Quadruple Aim of increased readiness, better health, better care, and lower cost.


Subject(s)
Mandibular Advancement , Sleep Apnea, Obstructive , Humans , Treatment Outcome , Continuous Positive Airway Pressure , Sleep Apnea, Obstructive/diagnosis , Ambulatory Care Facilities
4.
Ir Med J ; 115(8): 648, 2022 Sep 15.
Article in English | MEDLINE | ID: mdl-36302268

ABSTRACT

Aim This audit is performed to see the bacteriology profiles in early-onset sepsis (EOS) and late-onset sepsis (LOS) to compare the microorganisms identified and the antibiotic sensitivity results against hospitals' guidelines for empiric treatment of early and late-onset sepsis. Methods We retrospectively collected the neonate's microbiological data from the laboratory which included the date blood culture (BC) samples were collected, patients' day of life when the samples were collected to determine whether it was EOS or LOS, time to positivity of BC, and antibiotic susceptibility results. Results In EOS, most infection was caused by Gram-positive organisms which were 12 out of 14 isolates (85.7%) with GBS as the most common pathogen identified. In LOS, the number of infections caused by Gram-negative organisms, which were 14 of 25 isolates (56%) was higher than those caused by Gram-positive organisms, which were 11 out of 25 isolates (44%). E. coli was identified as the leading pathogen causing BSI. All organisms were sensitive to the antibiotics used according to the protocol. Conclusion Escherichia coli was the most common organism and was sensitive to the first-line antibiotics used. Group B Streptococcus is still the main pathogen in EOS. The rate of antibiotic resistance is low. The audit showed the importance of analysing the bacteriological and antibiotic susceptibility pattern to ensure optimal treatments are administered to infants.


Subject(s)
Escherichia coli Infections , Sepsis , Infant, Newborn , Infant , Humans , Escherichia coli , Retrospective Studies , Sepsis/drug therapy , Sepsis/epidemiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use
5.
bioRxiv ; 2022 Jul 19.
Article in English | MEDLINE | ID: mdl-35898345

ABSTRACT

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus originated in wild bats from Asia, and as the resulting pandemic continues into its third year, concerns have been raised that the virus will expand its host range and infect North American wildlife species, including bats. Mexican free-tailed bats ( Tadarida brasiliensis : TABR) live in large colonies in the southern United States, often in urban areas, and as such, could be exposed to the virus from infected humans. We experimentally challenged wild TABR with SARS-CoV-2 to determine the susceptibility, reservoir potential, and population impacts of infection in this species. Of nine bats oronasally inoculated with SARS-CoV-2, five became infected and orally excreted moderate amounts of virus for up to 18 days post inoculation. These five subjects all seroconverted and cleared the virus before the end of the study with no obvious clinical signs of disease. We additionally found no evidence of viral transmission to uninoculated subjects. These results indicate that while TABR are susceptible to SARS-CoV-2 infection, infection of wild populations of TABR would not likely cause mortality. However, the transmission of SARS-CoV-2 from TABR to or from humans, or to other animal species, is a distinct possibility requiring further investigation to better define.

6.
Eye (Lond) ; 36(7): 1368-1372, 2022 07.
Article in English | MEDLINE | ID: mdl-34172947

ABSTRACT

BACKGROUND: To describe the clinical presentation, burden and antimicrobial resistance of Methicillin-Resistant Staphylococcus aureus (MRSA) eye infections and to recommend a streamlined protocol for the management of ocular MRSA colonisation detected by pre-operative screening. METHODS: A retrospective review of all ocular samples which resulted in the isolation of MRSA between 1st of January 2013 and 31st of December 2019 at the Royal Victoria Eye and Ear Hospital. RESULTS: A total of 185 samples taken from the ocular surface were MRSA positive. The majority were MRSA colonisation of the ocular surface obtained as part of an MRSA screen (139/6955 patients screened; 2%). Forty-six represented MRSA infections (46/7904 eye samples; 0.58%), most occurring in older patients the majority of whom had known local or systemic risk factors for colonisation. The most common presentation was conjunctivitis (n = 24), followed by pre-septal cellulitis (n = 9). MRSA infections with the poorest clinical outcomes and the longest inpatient stay, were keratitis (n = 6) and post-operative endophthalmitis (n = 2). Our study demonstrated over 60% resistance to azithromycin, fusidic acid and ciprofloxacin, although resistance to chloramphenicol was uncommon. CONCLUSION: This study demonstrates that MRSA infections of the eye most commonly manifest as a mild infection, typically conjunctivitis, and are generally non-sight threatening. The majority of presentations occur in the context of known MRSA risk factors and in an older populous. Resistance to chloramphenicol is rare, thus it remains an excellent first line treatment. Its use to eradicate MRSA from the ocular surface is proposed to streamline the delivery of surgical eye care.


Subject(s)
Conjunctivitis , Eye Infections, Bacterial , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Aged , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Chloramphenicol/therapeutic use , Conjunctivitis/drug therapy , Eye Infections, Bacterial/drug therapy , Eye Infections, Bacterial/epidemiology , Humans , Staphylococcal Infections/drug therapy , Staphylococcal Infections/epidemiology
7.
Med Probl Perform Art ; 36(3): 163-175, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34464962

ABSTRACT

OBJECTIVE: To explore the subjective experiences of student circus arts performers with atraumatic shoulder instability undertaking a 12-week shoulder rehabilitation program during the COVID-19 pandemic lockdown, in Melbourne, Australia. METHODS: Using a qualitative design, 14 circus arts students from the National Institute of Circus Arts (Australia) were individually interviewed via teleconsultation. All interviews were recorded, transcribed, and analysed using inductive thematic analysis. RESULTS: Five overarching themes were identified: (i) impact (physical and mental), (ii) opportunity, (iii) developing routine, (iv) client-therapist relationship, and (v) transformation. All participants reported positive physical changes to their shoulder including increases in strength, stability, range of motion, less pain, "clicking" and "clunking," improved posture, muscle memory, as well as carry-over to functional circus activities. The pandemic's mental impact varied across the cohort, with positive and negative experiences described in relation to cognitive, social, and affective factors. Most performers felt the pandemic provided an opportunity to focus on rehabilitation of their shoulder. The program effects were also underpinned by positive client-therapist relationships and a progressive transformation of learning where students gained knowledge of their condition, developed tools to manage their current shoulder impairment, and learned how to apply this new knowledge to future management of their condition. CONCLUSION: A shoulder exercise intervention delivered via teleconsultation during the COVID-19 pandemic resulted in subjective reports of positive physical changes to the participants' shoulder health complaint. This was facilitated through client-physiotherapist relationships, providing structure during uncertain times, and by providing education to help in understanding their condition and its future management.


Subject(s)
COVID-19 , Joint Instability , Shoulder Joint , Telemedicine , Communicable Disease Control , Humans , Pandemics , Referral and Consultation , SARS-CoV-2 , Shoulder , Students
8.
Anaesth Rep ; 9(2): e12130, 2021.
Article in English | MEDLINE | ID: mdl-34458851

ABSTRACT

Insect damage to, and sub-optimal harvesting practices of the Papaver somniferum poppy are associated with contamination of its seeds with opium alkaloids. Consumption of poppy seeds has been linked to opium-like overdose symptoms, such as reduced consciousness and respiratory depression. However, acute cardiotoxicity secondary to ingestion of contaminated poppy seeds has not been reported previously. We report a case of a 21-year-old man who presented with severe biventricular dysfunction and cardiogenic shock following consumption of homemade poppy seed tea. We highlight the importance of prompt recognition of the myocardial effects of opiates along with the more common respiratory and neurological effects. In this case, the acute cardiotoxicity was fully reversed with high-dose naloxone, milrinone and noradrenaline. In addition, we recommend offering high-level care due to the possibility that specialist cardiac services may be required. Ergo, early transfer to an appropriate centre is recommended.

9.
J Psychosom Res ; 149: 110596, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34418720

ABSTRACT

BACKGROUND AND AIMS: Using the Common Sense Model (CSM), this study aimed to examine the extent to which illness beliefs, coping styles, self-efficacy, and mindfulness mediate this relationship. METHODS: Two hundred and sixty-one adults (198 females; 169 with Crohn's Disease) with IBD participated in this cross-sectional study. Measures used in this study were the short Crohn's Disease Activity Index, Ulcerative Colitis Lichtiger Index, Inflammatory Bowel Disease Questionnaire, New General Self-Efficacy Scale, Carver Brief COPE scale, Mindful Attention Awareness Scale, Brief Illness Perceptions Questionnaire, and the Depression and Anxiety Stress Scales. RESULTS: Using structural equation modelling, the final model indicated IBD symptoms had a significant direct influence only on illness perceptions (ß = 0.66, p < .001). In turn, illness perceptions had a significant direct influence on depression and anxiety (ß = 0.34, p < .001) and QoL (ß = -0.67, p < .001), and was also linked to higher maladaptive coping (ß = 0.28, p < .001) and lower self-efficacy (ß = -0.49, p < .001), but not with mindfulness or adaptive coping (p > .05). Maladaptive coping (ß = 0.46, p < .001) and mindfulness (ß = 0.23, p < .001) were linked with increased distress. QoL was influenced by distress (ß = -0.40, p < .001). CONCLUSIONS: Consistent with the predictions of the CSM, the relationships between IBD symptoms and depression and anxiety, and between IBD symptoms and quality of life, are statistically mediated via psychological variables including illness perceptions and maladaptive coping.


Subject(s)
Inflammatory Bowel Diseases , Psychological Distress , Adaptation, Psychological , Adult , Anxiety , Cross-Sectional Studies , Depression , Female , Humans , Quality of Life , Stress, Psychological , Surveys and Questionnaires
10.
BMC Health Serv Res ; 21(1): 706, 2021 Jul 18.
Article in English | MEDLINE | ID: mdl-34273978

ABSTRACT

BACKGROUND: Successful implementation of digital health systems requires contextually sensitive solutions. Working directly with system users and drawing on implementation science frameworks are both recommended. We sought to combine Normalisation Process Theory (NPT) with participatory co-design methods, to work with healthcare stakeholders to generate implementation support recommendations for a new electronic patient reported outcome measure (ePRO) in renal services. ePROs collect data on patient-reported symptom burden and illness experience overtime, requiring sustained engagement and integration into existing systems. METHODS: We identified co-design methods that could be mapped to NPT constructs to generate relevant qualitative data. Patients and staff from three renal units in England participated in empathy and process mapping activities to understand 'coherence' (why the ePRO should be completed) and 'cognitive participation' (who would be involved in collecting the ePRO). Observation of routine unit activity was completed to understand 'collective action' (how the collection of ePRO could integrate with service routines). RESULTS: The mapping activities and observation enabled the research team to become more aware of the key needs of both staff and patients. Working within sites enabled us to consider local resources and barriers. This produced 'core and custom' recommendations specifying core needs that could be met with customised local solutions. We identified two over-arching themes which need to be considered when introducing new digital systems (1) That data collection is physical (electronic systems need to fit into physical spaces and routines), and (2) That data collection is intentional (system users must be convinced of the value of collecting the data). CONCLUSIONS: We demonstrate that NPT constructs can be operationalised through participatory co-design to work with stakeholders and within settings to collaboratively produce implementation support recommendations. This enables production of contextually sensitive implementation recommendations, informed by qualitative evidence, theory, and stakeholder input. Further longitudinal evaluation is necessary to determine how successful the recommendations are in practice.


Subject(s)
Electronics , Patient Reported Outcome Measures , England , Humans , Qualitative Research , United Kingdom
11.
Ir Med J ; 114(10): 489, 2021 Dec 16.
Article in English | MEDLINE | ID: mdl-37669121

ABSTRACT

Aim Peritonsillar abscess (PTA) is the most common suppurative complication of acute tonsillitis. It requires urgent specialist treatment due to the risk of progression to airway compromise. We aimed to review referral pathways to a dedicated otolaryngology emergency department (ORL-ED), identify causative organisms and discuss COVID-19 implications. Methods A retrospective review of patients presenting to the ORL-ED between January 2018 and December 2019 was undertaken. Data extracted included demographics, referral source, treatment, microbiology results and length of stay. Statistical analysis of seasonal variation of presentation and causative organisms employed Chi-Square and Fisher's Exact Test, respectively. Results There were 53 PTA presentations. 51 were admitted accounting for 44.3% (51/115) of ED admissions. The median patient age was 31 years (IQR 20-40yrs). GP referral accounted for 48/53 (90.6%). There was no statistically significant seasonality (χ2=5.94, p=0.11) in presentation. Microbiology samples were available for 44 patients. Streptococcus was identified in 19/44 (43.2%) patients. 85% (45/53) of patients received Co-amoxiclav. Discussion PTA is a perennial condition with diverse causative organisms. Antibiotic choice should reflect this. The majority of patients are referred from primary care, emphasising the role of the GP in initial diagnosis and the importance of clinical education in this regard.

12.
J Nutr Sci ; 9: e25, 2020.
Article in English | MEDLINE | ID: mdl-32742642

ABSTRACT

Diet has a major influence on the composition and metabolic output of the gut microbiome. Higher-protein diets are often recommended for older consumers; however, the effect of high-protein diets on the gut microbiota and faecal volatile organic compounds (VOC) of elderly participants is unknown. The purpose of the study was to establish if the faecal microbiota composition and VOC in older men are different after a diet containing the recommended dietary intake (RDA) of protein compared with a diet containing twice the RDA (2RDA). Healthy males (74⋅2 (sd 3⋅6) years; n 28) were randomised to consume the RDA of protein (0⋅8 g protein/kg body weight per d) or 2RDA, for 10 weeks. Dietary protein was provided via whole foods rather than supplementation or fortification. The diets were matched for dietary fibre from fruit and vegetables. Faecal samples were collected pre- and post-intervention for microbiota profiling by 16S ribosomal RNA amplicon sequencing and VOC analysis by head space/solid-phase microextraction/GC-MS. After correcting for multiple comparisons, no significant differences in the abundance of faecal microbiota or VOC associated with protein fermentation were evident between the RDA and 2RDA diets. Therefore, in the present study, a twofold difference in dietary protein intake did not alter gut microbiota or VOC indicative of altered protein fermentation.


Subject(s)
Diet, High-Protein , Dietary Proteins , Microbiota/drug effects , Aged , Feces/chemistry , Feces/microbiology , Gastrointestinal Microbiome , Humans , Male , Nutritional Requirements , Treatment Outcome , Volatile Organic Compounds/analysis
13.
Ir Med J ; 113(6): 101, 2020 06 11.
Article in English | MEDLINE | ID: mdl-32816436

ABSTRACT

This is the first documented case of an infant with congenital Zika virus infection (ZVI) born in Ireland. A term infant was delivered with an antenatal diagnosis of severe microcephaly. First trimester bloods confirmed maternal ZVI and although the infant did not have Zika virus RNA or Zika-specific IgM in her blood or urine, she had multiple clinical features of congenital ZVI and Zika virus RNA was present in the placenta.


Subject(s)
Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/virology , Zika Virus Infection/congenital , Zika Virus Infection/diagnosis , Zika Virus , Biomarkers/analysis , Diffusion Magnetic Resonance Imaging , Female , Humans , Immunoglobulin M/analysis , Infant , Infant, Newborn , Ireland , Maternal-Fetal Exchange , Microcephaly/diagnosis , Microcephaly/virology , Placenta/metabolism , Placenta/virology , Pregnancy , Pregnancy Trimester, First , Prenatal Diagnosis , Prenatal Exposure Delayed Effects , RNA, Viral/analysis , Severity of Illness Index , Zika Virus/genetics , Zika Virus/immunology , Zika Virus Infection/virology
14.
Curr Oncol ; 27(3): e326-e331, 2020 06.
Article in English | MEDLINE | ID: mdl-32669940

ABSTRACT

Background: Oncoplastic surgery (ops) is becoming the new standard of care for breast-conserving surgery, leading to some challenges with adjuvant radiation, particularly when accurate tumour bed (tbd) delineation is needed for focused radiation (that is, accelerated partial breast irradiation or boost radiation). Currently, no guidelines have been published concerning tbd localization for adjuvant targeted radiation after ops. Methods: A modified Delphi method was used to establish consensus by a panel of 20 experts in surgical and radiation oncology at the Canadian Locally Advanced Breast Cancer National Consensus Group and in a subsequent online member survey. Results: These are the main recommendations:■ Surgical clips are necessary and should, at a minimum, be placed along the 4 side walls of the cavity, plus 1-4 clips at the posterior margin if necessary.■ Operative reports should include pertinent information to help guide the radiation oncologists.■ Breast surgeons and radiation oncologists should have a basic understanding of ops techniques and work on "speaking a common language."■ Careful consideration is needed when determining the value of targeted radiation, such as boost, in higher-level ops procedures with extensive tissue rearrangement. Conclusions: The panel developed a total of 6 recommendations on tbd delineation for more focused radiation therapy after ops, with more than 80% agreement on each statement. All are summarized, together with the corresponding evidence or expert opinion.


Subject(s)
Breast Neoplasms/radiotherapy , Breast Neoplasms/surgery , Mastectomy, Segmental/methods , Radiotherapy, Adjuvant/methods , Breast Neoplasms/pathology , Consensus , Female , Humans
15.
Ir Med J ; 113(4): 57, 2020 04 03.
Article in English | MEDLINE | ID: mdl-32268050

ABSTRACT

Aims To determine the impact of applying the Neonatal Early Onset Sepsis Calculator (NEOSC) to clinical practice. We evaluated this multivariable risk prediction model, used in the assessment of infants >35 weeks GA, at risk of neonatal sepsis. Methods A retrospective, cohort study comparing the rates of blood culture use in a large maternity hospital before and after the introduction of the NEOSC. Cases were ascertained from the records of the Department of Microbiology. The key variables were the number of blood cultures (all gestational ages, <72 hours old), infant antibiotic use and sepsis rates. Data for three years prior to NEOSC use (January 2015 - December 2017) were compared with 15 months (January 2018 - Q1 2019) after it was implemented. Results Pre- and post- NEOSC use, the total blood cultures taken annually were: 1,312 (2015), 1,149 (2016), 1,319 (2017) and 702 (2018), 192 (Q1 2019) respectively, a statistically significant reduction [p < 0.00001, 95% CI]. There was no significant difference in rates of either: culture-confirmed GBS-sepsis [p value 0.18, 95% CI] or other-pathogen sepsis [p value 0.32, 95%CI] in term infants between the two periods. There was a significant reduction in antibiotic use in the first 24 hours of life (average 11.3% pre-NEOSC and 5.9% after NEOSC was implemented) [p < 0.00001, 95% CI]. Conclusion The introduction of the NEOSC has reduced blood culture and antibiotic use. This has been achieved without any increase in infection rates.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Blood Culture/statistics & numerical data , Drug Utilization/statistics & numerical data , Neonatal Sepsis , Risk Assessment/methods , Age of Onset , Female , Forecasting , Humans , Inappropriate Prescribing/prevention & control , Infant, Newborn , Male , Neonatal Sepsis/epidemiology , Neonatal Sepsis/microbiology , Retrospective Studies , Risk , Time Factors , Unnecessary Procedures/statistics & numerical data
16.
Nanotechnology ; 31(10): 10LT01, 2019 Nov 26.
Article in English | MEDLINE | ID: mdl-31770739

ABSTRACT

Achieving a full understanding of the noise in resistive pulse sensing experiments is central to the development of this important single molecule technique. Here, we present a comprehensive study of the noise properties of conical glass nanopores as components in an ionic circuit by studying the power spectral density of the system in salt solutions at a range of concentrations. We begin by investigating the ionic current rectification of the pores, showing that it is only observed above a critical Dukhin number in agreement with theoretical predictions. We then investigate the noise properties of the pores and demonstrate that the fluctuations in the ionic current at no applied potential difference can be well modelled over four decades of frequency as thermal fluctuations over a complex impedance. Finally, we show that-when an ionic current flows-1/f noise dominates the power spectrum below ∼100 Hz. Fluctuations in the surface current govern the low-frequency 1/f noise, with the asymmetric shape of the pore leading the magnitude to scale with [Formula: see text], faster than predicted by Hooge's empirical relation.

17.
J Nutr Health Aging ; 23(4): 354-363, 2019.
Article in English | MEDLINE | ID: mdl-30932134

ABSTRACT

BACKGROUND: The mammalian target of rapamycin complex 1 (mTORC1) is fundamental for many cellular processes, yet it is often dysregulated with aging. Increased amino acid (AA) availability is correlated with the expression of AA transporters (AAT) and mTORC1 activity. Although many AA sensors and mediators have been proposed to relay the AA signal to mTORC1, it has not yet been determined if chronic dietary intervention affects the expression of AAT, sensors and mediators and their relationships with mTORC1 activity. OBJECTIVE AND DESIGN: This study investigated whether the consumption of a diet containing either the current recommended daily allowance (RDA) of protein intake (0.8 g/kg/d) or twice the RDA (2RDA) for ten weeks affected the expression of targets associated with AA transport, sensing and mTORC1 regulation in 26 older men (70-81 years). METHOD: Muscle biopsies were collected before and after the intervention under fasting conditions. Diets were controlled by providing fully prepared meals and snacks. Western blot and quantitative polymerase chain reaction were used to measure protein and gene expression respectively. RESULTS: Consumption of 2RDA reduced the protein expression of L-type amino acid transporter 1 (LAT1). However, plasma leucine concentration and basal mTORC1 activity were unaltered. The downregulation of LAT1 did not affect the expression of AA sensors and mediators, including leucyl tRNA synthetase (LRS), cytosolic arginine sensor for mTORC1 (CASTOR1), Sestrin2 and Rag proteins. Instead, total ribosomal protein S6 (RPS6) was upregulated with 2RDA. CONCLUSION: Ten weeks of 2RDA diet did not affect the fasting mTORC1 signaling, but increased total RPS6 might suggest improved muscular translational capacity to maintain muscular mass.


Subject(s)
Diet, High-Protein , Large Neutral Amino Acid-Transporter 1/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Muscle, Skeletal/physiology , Aged , Aged, 80 and over , Aging , Body Mass Index , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Leucine/chemistry , Male , Multiprotein Complexes , Recommended Dietary Allowances , Ribosomal Protein S6/metabolism , Signal Transduction
18.
Ecol Lett ; 22(5): 826-837, 2019 May.
Article in English | MEDLINE | ID: mdl-30868708

ABSTRACT

The mammalian gut microbiota is considered pivotal to host fitness, yet the determinants of community composition remain poorly understood. Laboratory studies show that environmental factors, particularly diet, are important, while comparative work emphasises host genetics. Here, we compare the influence of host genetics and the environment on the microbiota of sympatric small mammal species (mice, voles, shrews) across multiple habitats. While sharing a habitat caused some microbiota convergence, the influence of species identity dominated. In all three host genera examined, an individual's microbiota was more similar to conspecifics living elsewhere than to heterospecifics at the same site. Our results suggest this species-specificity arises in part through host-microbe codiversification. Stomach contents analysis suggested that diet also shapes the microbiota, but where diet is itself influenced by species identity. In this way, we can reconcile the importance of both diet and genetics, while showing that species identity is the strongest predictor of microbiota composition.


Subject(s)
Gastrointestinal Microbiome , Mammals , Microbiota , Animals , Mammals/microbiology , Mice , Sympatry
20.
Psychol Health Med ; 23(10): 1168-1181, 2018 12.
Article in English | MEDLINE | ID: mdl-29882424

ABSTRACT

The aim of the current study was to use Structural Equation Modelling (SEM) to examine whether psychological flexibility (i.e. mindfulness, acceptance, valued-living) mediates the relationship between distress, irritable bowel syndrome (IBS) symptom frequency, and quality of life (QoL). Ninety-two individuals participated in the study (12 male, 80 female, Mage = 36.24) by completing an online survey including measures of visceral sensitivity, distress, IBS-related QoL, mindfulness, bowel symptoms, pain catastrophizing, acceptance, and valued-living. A final model with excellent fit was identified. Psychological distress significantly and directly predicted pain catastrophizing, valued-living, and IBS symptom frequency. Pain catastrophizing directly predicted visceral sensitivity and acceptance, while visceral sensitivity significantly and directly predicted IBS symptom frequency and QoL. Symptom frequency also had a direct and significant relationship with QoL. The current findings suggest that interventions designed to address unhelpful cognitive processes related to visceral sensitivity, pain catastrophizing, and psychological distress may be of most benefit to IBS-related QoL.


Subject(s)
Catastrophization/psychology , Irritable Bowel Syndrome/psychology , Quality of Life/psychology , Stress, Psychological/psychology , Visceral Pain/psychology , Adult , Anxiety/psychology , Depression/psychology , Female , Humans , Irritable Bowel Syndrome/physiopathology , Male , Middle Aged , Mindfulness , Severity of Illness Index , Surveys and Questionnaires , Visceral Pain/physiopathology , Young Adult
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