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1.
Vet Ophthalmol ; 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38862255

ABSTRACT

A 9-year-old, female spayed domestic short-haired cat was presented with a 4-year history of bilateral lipogranulomatous conjunctivitis (LGC), which was confirmed via histopathology. Thirteen months following the initial biopsy, the cat was presented with a rapidly progressive mass lesion of the palpebral conjunctiva of the right eye. A surgical debulking, followed 1 month later by exenteration after marked regrowth of the mass confirmed fibrosarcoma. This case report is the first to describe a cat with chronic bilateral LGC that later developed a unilateral fibrosarcoma within the eyelid tissue of the right eye. Fibrosarcoma should be considered a differential in any cat with chronic LGC that develops a rapidly progressive mass in the eyelid.

2.
ACS Omega ; 8(42): 39437-39446, 2023 Oct 24.
Article in English | MEDLINE | ID: mdl-37901528

ABSTRACT

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) make up a group of anthropogenic chemicals with a myriad of applications. However, some PFAS have been shown to negatively impact human health and the environment, leading to increased regulation, with some countries making efforts to phase out their use. PFAS fate in the environment is driven by physical, chemical, and biological processes, with microbial communities in matrices such as soil and sewage sludge being known to generate a range of low-molecular-weight PFAS metabolites. Proposed metabolic intermediates for both mixed and pure microbial cultures include fluorinated carboxylates that may be activated by CoA prior to ß-oxidation and defluorination, although thus far, no PFAS-CoA adducts have been reported. Herein, we expressed and purified acyl-CoA synthetase (ACS) from the soil bacterium Gordonia sp. strain NB4-1Y and performed an analysis of substrate scope and enzyme kinetics using fluorinated and nonfluorinated carboxylates. We determined that ACS was able to catalyze the formation of CoA adducts of 3,3,3-trifluoropropionic acid, 5,5,5-trifluoropentanoic acid, 4,5,5-trifluoropent-4-enoic acid, and 4,4,5,5,5-pentafluoropentanoic acid. Kinetic analysis revealed a 90-98% decrease in kcat between nonfluorinated carboxylates and their fluorinated analogues. This provides evidence to validate proposed enzymatic pathways for microbial PFAS metabolism that proceed via an activation step involving the formation of CoA adducts.

3.
Occup Med (Lond) ; 73(7): 398-403, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37499056

ABSTRACT

BACKGROUND: Clinician reactions to client suicide may include shock, grief, guilt, self-doubt, shame, anger, and fears of blame and medico-legal consequences. Clinicians will often differ in their reactions to the suicide and the type of supports required. Adolescent suicide-specific literature is limited. AIMS: We sought to explore clinician reactions and perceptions of support following child and adolescent suicide. METHODS: One hundred and fifteen staff working for a Child and Adolescent Mental Health Service were invited to complete an online survey with quantitative and qualitative components, and an in-depth semi-structured interview. Results were presented to teams for reflection and further feedback. RESULTS: Eight clinicians participated in the semi-structured interview, and 33 in the online survey. Thirteen were the primary clinician, and 21 were part of a multi-disciplinary team when a client suicided. Respondents were predominantly female, from a range of disciplines. Fifty per cent of primary clinicians found the support good to very good. The rest were neutral. However, 26% of team members found support poor to very poor. Clinicians reported questioning their clinical effectiveness and chosen vocation. Some reported a need to disconnect or withdraw to preserve motivation and empathy for the work. They received significant support from their team, and teams were very anxious for the well-being of primary clinicians. CONCLUSIONS: Health services must find ways of helping staff feel that their sense of vocation is valued and nurtured. These strategies will likely include fostering team cohesiveness and mutual support and allowing opportunities to temporarily step back and recover after challenging experiences.

4.
J Exp Anal Behav ; 118(3): 376-397, 2022 11.
Article in English | MEDLINE | ID: mdl-36054301

ABSTRACT

Differential reinforcement of alternative behavior (DRA) involves placing problem behavior under extinction and simultaneously reinforcing a desirable behavior. Recent research revealed that, as predicted by Behavioral Momentum Theory, DRA may also increase the persistence of the problem behavior. This research has also shown that a different approach to DRA, in which an alternative behavior is trained in a separate context from the target behavior, produces less persistence than the standard procedure. The research on this phenomenon, so far, assessed persistence using extinction as the disruptor. DRA, however, is often implemented under conditions in which extinction of the problem behavior is not feasible. This study evaluated persistence of problem behavior following same- and separate- context DRA training using an alternative disruptor, an additional source of reinforcement. Following a successful reproduction of a previous study of extinction as a disruptor but with domestic hens, this study produced similar findings using an additional source of reinforcement as the disruptor. These findings add to the evidence that alternative DRA arrangements may avoid the response-strengthening effects found with traditional DRA procedures. The findings also demonstrate that disruptors other than extinction can be used to investigate response persistence following DRA and other procedures.


Subject(s)
Chickens , Extinction, Psychological , Animals , Female , Reinforcement Schedule , Reinforcement, Psychology , Behavior Therapy/methods
5.
Carbohydr Polym ; 288: 119361, 2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35450626

ABSTRACT

A multi-analytical study was performed to analyse the effect of bacterial cellulose (BCF) on the self-association of starches with different amylose content (wheat, waxy-maize), assessing macrostructural properties (rheology, gel strength) and some nano and sub-nano level features (small and wide-angle X-ray scattering). Although pasting viscosities and G' were significantly increased by BCF in both starches, cellulose did not seem to promote the self-association of amylose in short-range retrogradation. A less elastic structure was reflected by a 2-3-fold increase in loss factor (G″/G') at the highest BCF concentration tested. This behavior agreed with the nano and sub-nano characterisation of the samples, which showed loss of starch lamellarity and incomplete full recovery of an ordered structure after storage at 4 °C for 24 h. The gel strength data could be explained by the contribution of BCF to the mechanical response of the sample. The information gained in this work is relevant for tuning the structure of tailored starch-cellulose composites.


Subject(s)
Amylose , Cellulose , Amylose/chemistry , Rheology , Starch/chemistry , Viscosity
6.
J Nutr Health Aging ; 26(4): 318-323, 2022.
Article in English | MEDLINE | ID: mdl-35450986

ABSTRACT

OBJECTIVES: To examine the relationship between Vitamin D status and pain intensity and disability in individuals with and without knee pain, and to examine the role of epigenetics in this relationship. DESIGN: Cross-sectional analysis of data from the UPLOAD-2 study (Understanding Pain and Limitations in OsteoArthritic Disease-2). PARTICIPANTS: 189 individuals aged 45-65 years and older. MEASUREMENTS: Serum Vitamin D levels, pain related interference and characteristic pain intensity measures, and the epigenetic clock GrimAge derived from blood analyses. RESULTS: Lower Vitamin D was associated with advanced epigenetic aging (AgeAccelGrim), greater pain and disability and that (AgeAccelGrim) mediated the relationship between Vitamin D status and self-reported pain (ab = -0.0799; CI [-0.1492, -0.0237]) and disability (ab = -0.0669; CI [-0.1365, -0.0149]) outcomes. CONCLUSION: These data support the notion that lifestyle factors such as nutrition status play a key role in aging process, as well as the development and maintenance of age-related diseases such as pain. Modifying nutrition status could help promote healthy aging and reduce pain.


Subject(s)
Independent Living , Vitamin D , Aging/genetics , Cross-Sectional Studies , Epigenesis, Genetic , Humans , Pain/genetics , Vitamins
7.
Resuscitation ; 170: 17-25, 2022 01.
Article in English | MEDLINE | ID: mdl-34748765

ABSTRACT

INTRODUCTION: Bystander cardiopulmonary resuscitation (BCPR) is strongly advocated by resuscitation councils for paediatric out-of-hospital cardiac arrests (OHCAs). However, there are limited reports on rates of BCPR in children and its relationship with return of spontaneous circulation (ROSC) or survival outcomes. OBJECTIVE: We describe the rate of BCPR and its association with any ROSC and survival- to- hospital-discharge. METHODS: We conducted retrospective analysis of prospectively collected paediatric (<18 years of age) OHCA cases in England; we included specialist registry patients treated by emergency medical services (EMS) with known BCPR status and outcome between January 2014 and November 2018. Data included patient demographics, aetiology, witness status, initial rhythm, EMS, season, time of day and bystander status. Associations between BCPR, and any ROSC and survival-to-hospital-discharge outcomes were explored using multivariable logistic regression. RESULTS: There were 2363 paediatric OHCAs treated across 11 EMS regions. BCPR was performed in 69.6% (1646/2363) of the cases overall (range 57.7% (206/367) to 83.7% (139/166) across EMS regions). Only 34.9% (550/1572) of BCPR cases were witnessed. Overall, any ROSC was achieved in 22.8% (523/2289) and survival to hospital discharge in 10.8% (225/2066). Adjusted odds ratio (aOR) for any ROSC was significantly improved following BCPR compared to no BCPR (aOR 1.37, 95% CI 1.03-1.81), but adjusted odds ratio for survival-to-hospital-discharge were similar (aOR 1.01, 95% CI 0.66-1.55). CONCLUSIONS: BCPR was associated with improved rates of any ROSC but not survival-to-hospital-discharge. Variations in EMS BCPR rates may indicate opportunities for regional targeted increase in public BCPR education.


Subject(s)
Cardiopulmonary Resuscitation , Emergency Medical Services , Out-of-Hospital Cardiac Arrest , Child , Cohort Studies , Humans , Out-of-Hospital Cardiac Arrest/epidemiology , Out-of-Hospital Cardiac Arrest/therapy , Registries , Retrospective Studies
8.
West Indian med. j ; 69(9): 599-605, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1515731

ABSTRACT

ABSTRACT Objective: To assess the impact of visual impairment on the quality of life (QOL) of patients with diabetic retinopathy attending the Retina Eye Clinic at the University Hospital of the West Indies (UHWI). Method: A questionnaire modelled from the National Eye Institute Visual Function Questionnaire (NEIVFQ-25) was administered to 150 patients with diabetic retinopathy. The questions ranged from concern with their vision, health and social problems to functional ability. The associations between an overall QOL score and level of visual impairment among other variables were assessed using chi-square test and the t test in the SPSS software. Results: The mean age was 56 ± 10 years. Sixty-six percent were females. Type 2 diabetes was more common in 63% and 79% of the females and males, respectively. There were significant negative associations between QOL and increased duration of diabetes mellitus (DM) (p = 0.016), reduced vision (left eye; p < 0.049), reduced monthly income (p = 0.008), lack of compliance with exercise (p = 0.021), and a special diet (p = 0.01). There were no significant relationships between QOL and age (p = 0.495), marital status (p = 0.318) and DM type (p = 0.651). Conclusion: Poorer QOL was associated with decreased left eye visual acuity, lower income and lack of compliance with exercise and special diet among patients with diabetic retinopathy at UHWI.

9.
Behav Processes ; 185: 104356, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33577832

ABSTRACT

Researchers have employed a variety of laboratory analogues of cryptic prey detection and applied signal detection to study factors influencing learning and performance in these ethological and applied scenarios. However, these procedural analogues do not appear to map closely onto their "real-world" counterparts, particularly with respect to the role of the "yes" (i.e., "attack") response and the payoff for this response (or its absence) on signal-present and signal-absent trials. Using domestic hens, we developed a procedural analogue in which a "yes" response requires some time to emit; such responses were reinforced only in the presence of a signal. In Experiment 1, we evaluated the influence of the "yes" response requirement by manipulating the number of responses required to qualify as a "yes" response. As the "yes" response requirement was increased, bias toward responding "no" increased, revealing that this is a critical factor controlling accuracy in this procedure. In Experiment 2, we evaluated the influence of signal probability and reinforcement rate on signal detection accuracy and found that neither of these factors significantly influenced accuracy or bias. These findings suggest that this procedural analogue may represent a valuable alternative for studying behaviour in relevant signal detection scenarios.


Subject(s)
Chickens , Columbidae , Animals , Female , Learning , Reinforcement Schedule , Reinforcement, Psychology
10.
J Appl Behav Anal ; 53(1): 121-133, 2020 01.
Article in English | MEDLINE | ID: mdl-30747448

ABSTRACT

Prospective memory is remembering to carry out a behavior on a particular occasion or at a specific time in the future. This form of remembering is critical for the daily functioning of children with autism spectrum disorder (ASD) and their functional independence from caregivers. We used a single-subject design to investigate whether reinforcement increased the accuracy of prospective remembering in the context of a computerized board game, Virtual Week, of four 6- to 7-year-old children diagnosed with ASD. Reinforcement increased accuracy for all participants compared to baseline performance and effects were maintained after reinforcement was discontinued for three of four children. This is the first study of which we are aware to use a reinforcement-based behavioral intervention to improve the prospective remembering of children with ASD. Limitations and areas for future research are discussed.


Subject(s)
Autism Spectrum Disorder/psychology , Memory , Reinforcement, Psychology , Caregivers , Child , Humans , Male
11.
BMC Psychiatry ; 19(1): 275, 2019 09 06.
Article in English | MEDLINE | ID: mdl-31492119

ABSTRACT

BACKGROUND: Suicide has profound effects on families and communities, but is a statistically rare event. Psychological autopsies using a case-control design allow researchers to examine risk factors for suicide, using a variety of sources to detail the psychological and social characteristics of decedents and to compare them to controls. The Suicide Support and Information System Case Control study (SSIS-ACE) aimed to compare psychosocial, psychiatric and work-related risk factors across three groups of subjects: suicide decedents, patients presenting to hospital with a high-risk self-harm episode, and general practice controls. METHODS: The study design includes two inter-related studies; one main case-control study: comparing suicide cases to general practice (GP) controls, and one comparative study: comparing suicide cases to patients presenting with high-risk self-harm. Consecutive cases of suicide and probable suicide are identified through coroners' registration of deaths in the defined region (Cork City and County, Ireland) and are frequency-matched for age group and gender with GP patient controls recruited from the same GP practice as the deceased. Data sources for suicide cases include coroners' records, interviews with health care professionals and proxy informants; data sources for GP controls and for high-risk self-harm controls include interviews with control, with proxy informants and with health care professionals. Interviews are semi-structured and consist of quantitative and qualitative parts. The quantitative parts include a range of validated questionnaires addressing psychiatric, psychosocial and occupational factors. The study adopts several methodological innovations, including accessing multiple data sources for suicide cases and controls simultaneously, recruiting proxy informants to examine consistency across sources. CONCLUSIONS: The study allows for the investigation of consistency across different data sources and contributes to the methodological advancement of psychological autopsy research. The study will also inform clinical and public health practice. The comparison between suicide cases and controls will allow investigation of risk and protective factors for suicide more generally, while the comparison with high-risk self-harm patients will help to identify the factors associated specifically with a fatal outcome to a self-harm episode. A further enhancement is the particular focus on specific work-related risk factors for suicide.


Subject(s)
Self-Injurious Behavior/psychology , Suicide/psychology , Adult , Autopsy , Case-Control Studies , Female , Humans , Ireland , Male , Middle Aged , Proxy , Research Design , Risk Factors , Surveys and Questionnaires , Work/psychology
12.
J Exp Anal Behav ; 112(1): 88-96, 2019 07.
Article in English | MEDLINE | ID: mdl-31250443

ABSTRACT

This study evaluated the ability of Killeen's (1994) Mathematical Principles of Reinforcement to account for the effects of changes in reinforcer quality on hens' rates of responding on fixed-ratio schedules. Hens were trained to peck a key on a fixed-ratio schedule of reinforcement and then experienced an ascending series of ratio values in two separate conditions. In different conditions, the food reinforcer was either wheat or puffed wheat. Response rates initially increased with increases in ratio requirement before eventually decreasing at larger ratios. Quantitative fits of the model accounted for the data well. The fits revealed that different foods were systematically associated with changes in the specific activation parameter, a, and these were consistent with previous reports of preference for those food items.


Subject(s)
Chickens , Reinforcement, Psychology , Animals , Conditioning, Operant , Female , Mathematics , Reinforcement Schedule , Reward
13.
Transl Anim Sci ; 2(1): 101-110, 2018 Feb.
Article in English | MEDLINE | ID: mdl-32704693

ABSTRACT

Traceability of beef attributes from small- and mid-sized farms through supply chains is a market barrier. The objective of this trial was to determine the influence of fabrication method on beef traceability system requirements. Individual identities of 54 animals were maintained through harvest, processing, packaging, and distribution. At harvest, each animal's unique radio frequency identification (RFID) animal identification number was transferred to a harvest label on each carcass quarter. Following transportation to a processor, nine carcasses were processed on alternating days by one of the two methods. Carcasses were fabricated, using a serial fabrication method (SFM), into wholesale cuts one at a time or fabricated using a parallel fabrication method (PFM), by processing multiple hindquarters or forequarters simultaneously into wholesale cuts. In-process labels were generated by scanning the two-dimensional (2D) barcode on the harvest label with a handheld mobile computer and printed from a wireless mobile printer. Tracking of SFM and PFM carcass quarters was accomplished by creating in-process labels for lugs and individual wholesale cuts, respectively. The process was recorded and the data was captured from video analysis. The mean number of in-process labels generated per carcass for SFM was 3.7 and for PFM was 30.9 (P < 0.01). The amount of time required for generating in-process labels for SFM (2 min 16 s) was less than PFM (8 min 45 s) (P = 0.01). The amount of time required to label each carcass was less (P < 0.01) for SFM (18 s) than for PFM (3 min 10 s) with in-process labels. Total cost of traceability, including fixed and consumable cost per carcass, was nearly twice as much for PFM ($17.98) than SFM ($9.02). Traceability, within both processing methods, was found to have 100% fidelity, as verified using DNA marker genotyping. Overall, the number of labels generated for traceability was less for SFM than that for PFM. The overall time spent on generating, applying, and removing labels was less for SFM than that for PFM. The total cost of traceability was approximately half for SFM compared with that for PFM; however both methods were able to track product accurately. Tracking of beef from individual animals, using RFID ear tags and 2D barcodes, appears to be feasible for the fabrication methods used in this study.

14.
J Exp Anal Behav ; 108(3): 414-432, 2017 11.
Article in English | MEDLINE | ID: mdl-29139112

ABSTRACT

Hens responded under multiple fixed-ratio schedules with equal response requirements and either a 1-s or a 6-s reinforcer. Upcoming reinforcer size was indicated by key color. Components were presented in a quasirandom series so that all four component transitions occurred. Postreinforcement pauses were affected by the upcoming and preceding reinforcer size, with longer pauses after large reinforcers followed by small reinforcers than when followed by large ones, and longer pauses after small reinforcers that were followed by small reinforcers rather than large ones. Pauses increased with fixed-ratio size and the effects of reinforcer size were larger the larger the ratio. When reinforcer size was not signaled-mixed fixed-ratio schedules-pauses were shorter after small than after large reinforcers. Signalling the upcoming reinforcer attenuated the effect of the previous reinforcer size on pause duration when small was followed by small and when either small or large by large, but enhanced the effect when large was followed by small. There was no effect of reinforcer size on pause duration when single fixed-ratio schedules were arranged. The effects of reinforcer size on pauses depends on the size and range of the fixed ratios as well as the exact procedures used in the study.


Subject(s)
Reinforcement Schedule , Reinforcement, Psychology , Reward , Animals , Chickens , Conditioning, Operant , Female
15.
Otolaryngol Head Neck Surg ; 157(4): 690-695, 2017 10.
Article in English | MEDLINE | ID: mdl-28695761

ABSTRACT

Objectives To evaluate the quality of life of patients with ongoing tinnitus. Study Design This was a cross-sectional study of patients with ongoing tinnitus. Setting The study was carried out in a tertiary hospital in southeastern Nigeria. Subjects and Methods Subjects are adults who presented to the otorhinolaryngology clinic with tinnitus as their primary complaint. Pure-tone audiometry, tinnitus pitch, and loudness matching were done. The Tinnitus Handicap Inventory (THI) questionnaire was used in assessing their quality of life. Results There were 63 participants within the age range of 16 to 74 years; 20 (31.7%) were male and 43 (68.3%) were female. The mean duration of tinnitus was 26.7 ± 38.1 months. Nineteen (30.2%) participants had bilateral tinnitus while 44 (69.8%) had unilateral tinnitus. The mean THI score was 36.6 ± 19.7. The most reported handicap was anxiety and difficulty with concentration followed by depression and irritability. There was no correlation between the disability shown by the THI score and the age, sex, duration of the tinnitus, the tinnitus pitch, tinnitus loudness, or the laterality of the tinnitus. There was a significant positive correlation between the grade of hearing loss and the level of disability reported in the THI ( P = .01). Conclusion Tinnitus sufferers appear to have poorer quality of life compared with nonsufferers. This quality-of-life affectation is likely to be worse in those with disabling hearing loss but does not appear to be related to their age, sex, symptom duration, or the loudness and pitch of their tinnitus.


Subject(s)
Loudness Perception/physiology , Quality of Life , Tinnitus/psychology , Adolescent , Adult , Aged , Audiometry, Pure-Tone , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Nigeria/epidemiology , Surveys and Questionnaires , Tinnitus/epidemiology , Tinnitus/physiopathology , Young Adult
16.
Int J Pediatr Otorhinolaryngol ; 92: 151-155, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28012518

ABSTRACT

OBJECTIVES: To assess the improvement or otherwise, in the mean pulmonary arterial pressure (mPAP) among children with adenotonsillar hypertrophy (ATH) after adenotonsillectomy (AT), and to examine the impact of timing of surgery as well as the patients' characteristics on the mPAP changes. METHODS: We included 39 children with ATH in this study. The adenoidal enlargement was evaluated radiologically with adenoid nasopharyngeal ratio (ANR) parameter from lateral neck radiograph, whereas the clinical assessment of adeno-tonsillar obstruction was conducted with the 'symptom score'. Pulmonary arterial pressure (PAP) measurement was performed noninvasively by Doppler echocardiography. All patients underwent adenotonsillectomy (AT). After 6 weeks, they were subjected again to clinical and echocardiographic assessments, and the mean pulmonary arterial pressures (mPAP) were then compared. The mPAP changes after AT were further related to the grades of ANR, symptom scores, tonsillar size, and timing of AT. RESULTS: The preoperative mPAP was 23.46 mmHg and was 18.98 mmHg post-operatively (P = 0.003). Seventeen of subjects (43.6%) had pulmonary hypertension (PH) (mPAP ≥ 25 mmHg) preoperatively, out of which 14 (82%) decreased to normal range 6 weeks after AT. Non-reversal of pulmonary hypertension was associated with ANR > 0.75 (P = 0.043), but was not related to the timing of surgery, tonsillar size, and symptom score. Significant reduction in mPAP was more likely with ANR ≤ 0.75 and pre-operative mPAP ≥ 25 mmHg. All the symptoms also improved significantly after AT. CONCLUSION: Elevated PAP due to ATH in children was mostly reversible by AT irrespective of the timing of surgery, symptom severity, and tonsillar size, but gross enlargement of adenoids seem to be associated with non-reversal of PH.


Subject(s)
Adenoidectomy/methods , Adenoids/pathology , Hypertension, Pulmonary/surgery , Palatine Tonsil/pathology , Pulmonary Artery/physiology , Tonsillectomy/methods , Africa, Western , Airway Obstruction/surgery , Arterial Pressure , Black People , Child , Child, Preschool , Echocardiography, Doppler , Female , Humans , Hypertrophy , Male
17.
Behav Brain Res ; 322(Pt B): 223-232, 2017 03 30.
Article in English | MEDLINE | ID: mdl-27180169

ABSTRACT

Increased human longevity has magnified the negative impact that aging can have on cognitive integrity of older individuals experiencing some decline in cognitive function. Approximately 30% of the elderly will have cognitive problems that influence their independence. Impaired executive function and memory performance are observed in normal aging and yet can be an early sign of a progressive cognitive impairment of Alzheimer's disease (AD), the most common form of dementia. Brain regions that are vulnerable to aging exhibit the earliest pathology of AD. Senescent synaptic function is observed as a shift in Ca2+-dependent synaptic plasticity and similar mechanisms are thought to contribute to the early cognitive deficits associated with AD. In the case of aging, intracellular redox state mediates a shift in Ca2+ regulation including N-methyl-d-aspartate (NMDA) receptor hypofunction and increased Ca2+ release from intracellular stores to alter synaptic plasticity. AD can interact with these aging processes such that molecules linked to AD, ß-amyloid (Aß) and mutated presenilin 1 (PS1), can also degrade NMDA receptor function, promote Ca2+ release from intracellular stores, and may increase oxidative stress. Thus, age is one of the most important predictors of AD and brain aging likely contributes to the onset of AD. The focus of this review article is to provide an update on mechanisms that contribute to the senescent synapse and possible interactions with AD-related molecules, with special emphasis on regulation of NMDA receptors.


Subject(s)
Aging/metabolism , Alzheimer Disease/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Synapses/metabolism , Animals , Humans , Oxidation-Reduction , Synaptic Transmission/physiology
18.
Eur Arch Otorhinolaryngol ; 274(3): 1237-1243, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27430227

ABSTRACT

Unrelieved upper airway obstruction from highly prevalent adenotonsillar hypertrophy (ATH) has the potential of producing structural remodelling of the pulmonary vascular bed with resultant pulmonary hypertension (PH) and cor pulmonale. This cross-sectional study aimed to determine the local prevalence of PH and examine its clinical and radiological pointers among children with ATH. The airway obstruction was evaluated clinically by grading the nocturnal and daytime symptoms of ATH. A Brodsky scale and adenoid-nasopharynx ratio (AN ratio) were used to categorize tonsil and adenoid size, respectively. Mean pulmonary artery pressure (mPAP), was measured noninvasively for each child using Doppler echocardiography and PH was defined by mPAP ≥25 mmHg. Comparison of symptom scores, tonsil and adenoid size and demographic factors was made between children with mPAP ≥25 mmHg and those mPAP <25 mmHg using univariate and multivariate analysis. There was 22.8 % (18/79) prevalence of PH among the 26 children with only adenoid hypertrophy and 53 with ATH. Significant risk factors identified by logistic regression analysis associated with PH were daytime mouth breathing, daytime stertor, and AN ratio >0.75 (P = 0.002, 0.018, and 0.04, respectively), with more than sixfold and fourfold increase risk for daytime mouth breathing and daytime stertor, respectively. Obstructive breathing during sleep was significant only on univariate analysis. Prolonged symptom duration ≥24 months, large tonsils (grades 3 and 4), snoring and mouth breathing during sleep were not significant. This study demonstrated that pulmonary hypertension remains prevalent in children with ATH. Daytime mouth breathing and stertor as well as AN ratio >0.75 are the prime predictors of pulmonary hypertension, with an AN ratio cut-off point of 0.73 on ROC analysis.


Subject(s)
Adenoids , Airway Obstruction , Hypertension, Pulmonary , Palatine Tonsil , Adenoids/diagnostic imaging , Adenoids/pathology , Airway Obstruction/complications , Airway Obstruction/etiology , Airway Obstruction/physiopathology , Child , Child, Preschool , Cross-Sectional Studies , Echocardiography, Doppler/methods , Female , Humans , Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/etiology , Hypertension, Pulmonary/physiopathology , Hypertrophy/complications , Male , Mouth Breathing/diagnosis , Mouth Breathing/etiology , Nigeria , Palatine Tonsil/diagnostic imaging , Palatine Tonsil/pathology , Predictive Value of Tests , Prognosis , Radiography/methods , Risk Factors , Symptom Assessment/methods
19.
Eur J Clin Microbiol Infect Dis ; 35(12): 1923-1931, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27604831

ABSTRACT

Staphylococcus aureus expresses two distinct but closely related multifunctional cell wall-anchored (CWA) proteins that bind to the host glycoprotein fibronectin. The fibronectin binding proteins FnBPA and FnBPB comprise two distinct domains. The C-terminal domain comprises a tandem array of repeats that bind to the N-terminal type I modules of fibronectin by the tandem ß-zipper mechanism. This causes allosteric activation of a cryptic integrin binding domain, allowing fibronectin to act as a bridge between bacterial cells and the α5ß1 integrin on host cells, triggering bacterial uptake by endocytosis. Variants of FnBPA with polymorphisms in fibronectin binding repeats (FnBRs) that increase affinity for the ligand are associated with strains that infect cardiac devices and cause endocarditis, suggesting that binding affinity is particularly important in intravascular infections. The N-terminal A domains of FnBPA and FnBPB have diverged into seven antigenically distinct isoforms. Each binds fibrinogen by the 'dock, lock and latch' mechanism characteristic of clumping factor A. However, FnBPs can also bind to elastin, which is probably important in adhesion to connective tissue in vivo. In addition, they can capture plasminogen from plasma, which can be activated to plasmin by host and bacterial plasminogen activators. The bacterial cells become armed with a host protease which destroys opsonins, contributing to immune evasion and promotes spreading during skin infection. Finally, some methicillin-resistant S. aureus (MRSA) strains form biofilm that depends on the elaboration of FnBPs rather than polysaccharide. The A domains of the FnBPs can interact homophilically, allowing cells to bind together as the biofilm accumulates.


Subject(s)
Adhesins, Bacterial/metabolism , Bacterial Adhesion , Endocytosis , Fibronectins/metabolism , Staphylococcus aureus/physiology , Biofilms/growth & development , Carrier Proteins/metabolism , Protein Binding , Protein Domains , Staphylococcus aureus/metabolism
20.
Int J Pediatr Otorhinolaryngol ; 89: 169-72, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27619051

ABSTRACT

OBJECTIVES: Despite a global improvement in health care delivery, rural areas in developing countries still have poor access to specialist care. This study aims to assess the occurrences of ear, nose, and throat (ENT) disorders among rural primary school children in south-eastern Nigeria. METHODS: Two rural primary schools were selected randomly from one of the rural regions of South Eastern State of Nigeria. All the pupils of the schools who gave consent were recruited. A structured study proforma investigating the pupils' biodata, otolaryngological symptoms, ear, nose and throat examination findings, was used to evaluate each pupil in the presence of the teachers. RESULTS: A total of 246 children participated in the study. 145(58.9%) were males while 101(41.1%) were females with a mean age of 8.5 ± 2.4 years. The commonest symptoms reported were nasal discharge (20%) followed by nasal obstruction (11.1%), itching of the ears (11.1%) and sneezing bouts (10%), while 3.7% had subjective hearing impairment. The commonest ENT finding was cerumen auris (43%) and this was observed in 43.4% of males and 42.4% of females, 11% had abnormal tympanic membranes and 20% had grades 3/4 tonsils(Brodsky grading). CONCLUSION: ENT disorders are still common in children in the rural areas of developing countries. To avoid the morbidity associated with these preventable and easily manageable disorders, community health workers should be trained to manage common ENT disorders and mobile clinics with scheduled visits made available in areas where ENT services remain inaccessible.


Subject(s)
Otorhinolaryngologic Diseases/epidemiology , Adolescent , Child , Child, Preschool , Female , Humans , Male , Nigeria/epidemiology , Prevalence , Rural Population , Schools/statistics & numerical data
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