Evaluation of kurtosis-corrected sound exposure level as a metric for predicting onset of hearing threshold shifts in harbor porpoises (Phocoena phocoena).

Application of a kurtosis correction to frequency-weighted sound exposure level (SEL) improved predictions of risk of hearing damage in humans and terrestrial mammals for sound exposures with different degrees of impulsiveness. To assess whether kurtosis corrections may lead to improved predictions for marine mammals, corrections were applied to temporary threshold shift (TTS) growth measurements for harbor porpoises (Phocoena phocoena) exposed to different sounds. Kurtosis-corrected frequency-weighted SEL predicted accurately the growth of low levels of TTS (TTS1-4 < 10 dB) for intermittent sounds with short (1-13 s) silence intervals but was not consistent with frequency-weighted SEL data for continuous sound exposures.

Modeling potential masking of echolocating sperm whales exposed to continuous 1-2 kHz naval sonar.

Modern active sonar systems can (almost) continuously transmit and receive sound, which can lead to more masking of important sounds for marine mammals than conventional pulsed sonar systems transmitting at a much lower duty cycle. This study investigated the potential of 1-2 kHz active sonar to mask echolocation-based foraging of sperm whales by modeling their echolocation detection process. Continuous masking for an echolocating sperm whale facing a sonar was predicted for sonar sound pressure levels of 160 dB re 1 µPa2, with intermittent masking at levels of 120 dB re 1 µPa2, but model predictions strongly depended on the animal orientation, harmonic content of the sonar, click source level, and target strength of the prey. The masking model predicted lower masking potential of buzz clicks compared to regular clicks, even though the energy source level is much lower. For buzz clicks, the lower source level is compensated for by the reduced two-way propagation loss to nearby prey during buzzes. These results help to predict what types of behavioral changes could indicate masking in the wild. Several key knowledge gaps related to masking potential of sonar in echolocating odontocetes were identified that require further investigation to assess the significance of masking.

Older age does not influence the success of weight loss through the implementation of lifestyle modification.

OBJECTIVE: Age is sometimes a barrier for acceptance of patients into a hospital-based obesity service. Our aim was to explore the effect of age on the ability to lose weight through lifestyle interventions, implemented within a hospital-based obesity service. DESIGN: Retrospective study. PATIENTS: We included a cohort of randomly selected patients with morbid obesity (n = 242), who attended our hospital-based obesity service during 2005-2016 and received only lifestyle weight loss interventions. MEASUREMENTS: Primary outcome measures were percentage weight loss (%WL) and percentage reduction in body mass index (%rBMI) following implemented lifestyle interventions. Data were stratified according to patient age at referral: group 1 (age < 60 years, n = 167) and group 2 (age ≥ 60 years, n = 75). Weight loss was compared between groups, and correlations with age at referral were explored. RESULTS: The duration of hospital-based weight loss interventions ranged between 1 and 143 months (mean: 38.9 months; SD: 32.3). Baseline BMI at referral differed significantly between groups 1 and 2 (49.7 kgm-2 [SD: 8.7] vs 46.9 kgm-2 [SD: 6.1], respectively; P < .05). Following implemented lifestyle interventions, between groups 1 and 2 there were no differences in %WL (6.9% [SD: 16.7] vs 7.3% [SD: 11.60], respectively; P = NS) or %rBMI (8.1% [SD: 14.9] vs 7.8% [SD: 11.7], respectively; p = NS). Overall, there was no significant correlation between patient age at referral and %WL (r = -.13, p = NS). CONCLUSIONS: Older age does not influence the success of weight loss through the implementation of lifestyle modification within a hospital-based obesity service. Therefore, age per se should not influence clinical decisions regarding acceptance of patients to hospital-based obesity services.

Influence of common clinical variables on intraoperative parathyroid hormone monitoring during surgery for primary hyperparathyroidism.

BACKGROUND: Intraoperative monitoring of parathyroid hormone (IOPTH) is a reliable method of predicting the cure of primary hyperparathyroidism (PHPT). The aim of this study is to assess whether common clinical variables (CCV) frequently encountered in patients with PHPT may affect the magnitude of PTH drop or the likelihood of patients meeting the intraoperative cure criterion. DESIGN: Patients who were surgically cured from PHPT caused by single gland disease (SGD) and had full IOPTH protocol (4 measurements) were stratified according to age, gland weight, renal function, vitamin D status and severity of hypercalcemia. The percentage of IOPTH drop and the frequency of patients who had true positive IOPTH test results were compared among groups. RESULTS: 762 patients had surgery for PHPT, of whom 746 were (98%) cured. Of these 746 patients, 511 who had SGD and a full IOPTH protocol were included in this study. The median IOPTH drop was significantly higher among younger patients, those with severe hypercalcaemia at 5, 10, 15 min after gland excision, giant glands (at 5-min only), patients with vitamin D deficiency (at 10, 15 min), and those with normal renal function (at 15 min only). The likelihood of the patients meeting the intraoperative cure criterion was not significantly affected among the groups except in patients with mild hypercalcaemia, who were significantly less likely to have 50% IOPTH drop than those with severe hypercalcaemia at all time points. The frequency of mildly hypercalcaemic patients who met cure criterion was significantly improved by extending measurement to 15 min. CONCLUSIONS: IOPTH monitoring has the ability to mitigate the variability of IOPTH kinetics associated with most clinical variables. Mildly hypercalcemic patients in particular may benefit from waiting for 15-min measurement before any surgical decision is made.

The impact of stroke on bone properties and muscle-bone relationship: a systematic review and meta-analysis.

To systematically review available evidence related to the characteristics of bone changes post-stroke and the relationship between various aspects of muscle function (e.g., strength, spasticity) and bone properties after stroke onset. An extensive online database search was undertaken (last search in January 2019). Articles that examined the bone properties in stroke patients were included. The quality of the studies was evaluated with the National Institutes of Health (NIH) Study Quality Assessment Tools. Publication bias of meta-analyses was assessed using the Egger's regression asymmetry test. The selection and evaluation of the articles were conducted by two independent researchers. Fifty-nine studies were identified. In subacute and chronic stroke studies, the skeletal sites in the paretic limbs sustained a more pronounced decline in bone quality than did their counterparts in the non-paretic limbs. The rate of changes showed a decelerating trend as post-stroke duration increased, but the timing of achieving the steady rate differed across skeletal sites. The magnitude of bone changes in the paretic upper limb was more pronounced than the paretic lower limb. There was a strong relationship between muscle strength/mass and bone density/strength index. Muscle spasticity seemed to have a negative impact on bone integrity in the paretic upper limb, but its influence on bone properties in the paretic lower limb was uncertain. Substantial bone changes in the paretic limbs occurred particularly in the first few months after stroke onset. Early intervention, muscle strength training, and long-term management strategies may be important to enhance bone health post-stroke. This review has also revealed the knowledge gaps which should be addressed in future research.

Predicting acoustic dose associated with marine mammal behavioural responses to sound as detected with fixed acoustic recorders and satellite tags.

To understand the consequences of underwater noise exposure for cetaceans, there is a need for assessments of behavioural responses over increased spatial and temporal scales. Bottom-moored acoustic recorders and satellite tags provide such long-term and large spatial coverage of behaviour compared to short-duration acoustic-recording tags. However, these tools result in a decreased resolution of data from which an animal response can be inferred, and no direct recording of the sound received at the animal. This study discusses the consequence of the decreased resolution of data from satellite tags and fixed acoustic recorders on the acoustic dose estimated by propagation modelling and presents a method for estimating the range of sound levels that animals observed with these methods have received. This problem is illustrated using experimental results obtained during controlled exposures of northern bottlenose whales (Hyperoodon ampullatus) exposed to naval sonar, carried out near Jan Mayen, Norway. It is shown that variability and uncertainties in the sound field, resulting from limited sampling of the acoustic environment, as well as decreased resolution in animal locations, can lead to quantifiable uncertainties in the estimated acoustic dose associated with the behavioural response (in this case avoidance and cessation of foraging).

Application of Mindfulness in a Tier 3 Obesity Service Improves Eating Behavior and Facilitates Successful Weight Loss.

Context: Mindfulness strategies may facilitate healthier eating behavior but have not previously been studied in a United Kingdom-based tier 3 obesity service. Objective: To demonstrate the clinical effectiveness of mindfulness as part of newly created group sessions within a tier 3 obesity service. Methods: Recruitment of participants (n = 53, including n = 33 completers) from patients attending a tier 3-based obesity service at University Hospitals Coventry and Warwickshire. Each participant attended four group sessions, at which mindfulness-based eating behavior strategies were taught. Self-reported eating behavior and body weight were assessed at baseline and following completion of attendance at the group sessions. Paired-sample t tests were performed. P < 0.05 was considered significant. Data are reported for the 33 completers. Weight difference was assessed in a retrospective control group of 33 patients who did not attend the group sessions but received the standard multidisciplinary input. Results: There were statistically significant improvements (P = 0.009) in self-reported eating behavior [driven by improvements in "fast-foodism" (P = 0.031)] and reduction in body weight [3.06 kg (SD 5.2 kg), P = 0.002] at 6 months following completion of the group sessions. This was statistically more (P = 0.036) than 6-month weight loss in the control group (0.21 kg). Participants reported improved self-esteem and confidence in self-management of body weight. Conclusion: Application of mindfulness-based eating behavior strategies, taught at group sessions within a tier 3 obesity service, resulted in significant improvement in eating behavior, and facilitated subsequent weight loss over 6 months. Such a strategy has potential for scalability to the wider obese population.

Effective Implementation of Peri-operative Local Guidelines for Metabolic Surgery in Patients with Diabetes Mellitus in a Tier 4 Setting Demonstrate Improved Work Efficiency and Resource Allocation.

BACKGROUND: Dynamic changes in glycaemia predominate peri-operatively in patients with type 2 diabetes mellitus (T2DM) undergoing metabolic surgery. There is a lack of consensus and clear guidance on effective glycaemic management of such patients. The aim of this study was to design, pilot, and implement a proforma to improve consistency of glycaemic management and clarity of communication with healthcare professionals following metabolic surgery in patients with T2DM, thereby reducing unnecessary diabetes specialist nurse (DSN) referrals. METHODS: A proforma was designed and piloted for 12 months to guide healthcare professionals on managing glycaemic therapies for T2DM patients undergoing metabolic surgery. Glycaemic control (HbA1c) and glycaemic therapies were reviewed 3 weeks pre-operatively and a proforma was completed accordingly. RESULTS: Of the patients with T2DM (n = 34) who underwent metabolic surgery prior to the new proforma being implemented, 71% (n = 24) had a DSN referral. Half of these referrals were deemed unnecessary by the DSNs. Of the patients with T2DM (n = 33) who underwent metabolic surgery following implementation of the proforma, 21% (n = 7) had a DSN referral. Only 10% of these were deemed unnecessary. Despite the reduced DSN input, no diabetes-related complications were reported. CONCLUSION: Implementation of our proforma effectively halved the proportion of patients with T2DM requiring a DSN referral. Additionally, there was a 40% absolute reduction in the proportion of unnecessary DSN referrals. The proforma improved clarity of communication and guidance for healthcare professionals in the glycaemic management of patients. This also facilitated improved work efficiency and resource allocation.

The evolution of methods for urinary steroid metabolomics in clinical investigations particularly in childhood.

The metabolites of cortisol, and the intermediates in the pathways from cholesterol to cortisol and the adrenal sex steroids can be analysed in a single separation of steroids by gas chromatography (GC) coupled to MS to give a urinary steroid profile (USP). Steroids individually and in profile are now commonly measured in plasma by liquid chromatography (LC) coupled with MS/MS. The steroid conjugates in urine can be determined after hydrolysis and derivative formation and for the first time without hydrolysis using GC-MS, GC-MS/MS and liquid chromatography with mass spectrometry (LC-MS/MS). The evolution of the technology, practicalities and clinical applications are examined in this review. The patterns and quantities of steroids changes through childhood. Information can be obtained on production rates, from which children with steroid excess and deficiency states can be recognised when presenting with obesity, adrenarche, adrenal suppression, hypertension, adrenal tumours, intersex condition and early puberty, as examples. Genetic defects in steroid production and action can be detected by abnormalities from the GC-MS of steroids in urine. New mechanisms of steroid synthesis and metabolism have been recognised through steroid profiling. GC with tandem mass spectrometry (GC-MS/MS) has been used for the tentative identification of unknown steroids in urine from newborn infants with congenital adrenal hyperplasia. Suggestions are made as to areas for future research and for future applications of steroid profiling. As routine hospital laboratories become more familiar with the problems of chromatographic and MS analysis they can consider steroid profiling in their test repertoire although with LC-MS/MS of urinary steroids this is unlikely to become a routine test because of the availability, cost and purity of the internal standards and the complexity of data interpretation. Steroid profiling with quantitative analysis by mass spectrometry (MS) after chromatography now provides the most versatile of tests of adrenal function in childhood.

Anesthesia for patients with tracheal bronchus.

Tracheal bronchus is a congenital anatomical variant of patients with accessory bronchus in the right upper lobe deriving directly from the supracarinal trachea. Pre-operative consultation with the anesthesiologist is important for patient safety and can avoid adverse effects induced by endotracheal intubation. In this report, we described a case of tracheal bronchus in which general anesthesia was performed for video-assisted thoracoscopic surgery. We discussed some of the issues surrounding to complications in tracheal bronchus.

Randomised clinical trial: rifaximin versus placebo for the treatment of functional dyspepsia.

BACKGROUND: Gut dysbiosis may contribute to pain and bloating in patients with functional gastrointestinal disease. AIMS: To determine if treatment with rifaximin would improve the symptoms of functional dyspepsia in Chinese patients in a double-blinded, randomised, placebo-controlled trial. METHODS: Consecutive subjects with a diagnosis of functional dyspepsia as per the Rome III criteria were randomised to receive rifaximin 400 mg or placebo, all taken three times daily for 2 weeks. The investigators and study subjects were blinded to the treatment allocation. Subjects were followed up for 8 weeks. The primary end point was adequate relief of global dyspeptic symptoms (GDS). Secondary endpoints were relief of individual dyspeptic symptoms. RESULTS: Eighty-six subjects were recruited. At week 8, there were significantly more subjects in the rifaximin than in the placebo group who experienced adequate relief of GDS (78% vs. 52%, P = 0.02). A trend favouring rifaximin group was also noted in the preceding 4 weeks. Rifaximin was also superior to placebo in providing adequate relief of belching and post-prandial fullness/bloating (PPF) in subjects at week 4. Subgroup analysis revealed that female subjects had more significant response to rifaximin treatment (adequate relief of GDS at week 4: 76% vs. 42%, P = 0.006; week 8: 79% vs. 47%, P = 0.008), as well as improvements in their belching and PPF at week 4. The incidences of adverse effects were similar in both groups. CONCLUSIONS: Treatment with 2 weeks of rifaximin led to adequate relief of global dyspeptic symptoms, belching and post-prandial fullness/bloating in subjects with functional dyspepsia. The difference was more marked in females. (clinicaltrials.org NCT01643083).

Opioid therapy for chronic non-cancer pain: guidelines for Hong Kong.

Opioids are increasingly used to control chronic non-cancer pain globally. International opioid guidelines have been issued in many different countries but a similar document is not generally available in Hong Kong. Chronic opioid therapy has a role in multidisciplinary management of chronic non-cancer pain despite insufficient evidence for its effectiveness and safety for long-term use. This document reviews the current literature to inform Hong Kong practitioners about the rational use of chronic opioid therapy in chronic non-cancer pain. It also aims to provide useful recommendations for the appropriate, effective, and safe use of such therapy in the management of chronic non-cancer pain in adults. Physicians should conduct a comprehensive biopsychosocial evaluation of patients prior to the commencement of opioid therapy. When opioid use is deemed appropriate, the patient should provide informed consent within an agreement that specifies treatment goals and expectations. A trial of opioid can be commenced and, provided there is progress towards treatment goals, then chronic therapy can be considered at a dose that minimises harm. Monitoring of effectiveness, safety, and drug misuse should be continued. Treatment should be stopped when opioids become ineffective, intolerable, or misused. The driving principles for opioid prescription in chronic pain management should be: start with a low dose, titrate slowly, and maintain within the shortest possible time.

Chronic effects of stroke on hip bone density and tibial morphology: a longitudinal study.

UNLABELLED: The study aimed to quantify the long-term effects of stroke on tibial bone morphology and hip bone density. Only the trabecular bone mineral density and bone strength index in the hemiparetic tibial distal epiphysis showed a significant decline among individuals who had sustained a stroke 12-24 months ago. INTRODUCTION: This study aims to determine the changes in bone density and morphology in lower limb long bones during a 1-year follow-up period and their relationship to muscle function in chronic stroke patients. METHODS: Twenty-eight chronic stroke patients (12-166 months after the acute stroke event at initial assessment) and 27 controls underwent bilateral scanning of the hip and tibia using dual-energy X-ray absorptiometry and peripheral quantitative computed tomography, respectively. Each subject was re-assessed 1 year after the initial assessment. RESULTS: Twenty stroke cases and 23 controls completed all assessments. At the end of the follow-up, the paretic tibial distal epiphysis suffered significant decline in trabecular bone density (-1.8 ± 0.6 %, p = 0.006) and bone strength index (-2.7 ± 0.6 %, p < 0.001). More severe decline in the former was associated with poorer leg muscle strength (ρ = 0.447, p = 0.048) and motor recovery (ρ = 0.489, p = 0.029) measured at initial assessment. The loss in trabecular bone density remained significant among those whose stroke onset was 12-24 months ago (p < 0.001), but not among those whose stroke onset was beyond 24 months ago (p > 0.05) at the time of initial assessment. The changes of outcomes in the tibial diaphysis, except for cortical bone mineral content on the non-paretic side (-1.3 ± 0.3 %, p = 0.003), and hip bone density were well within the margin of error for precision. CONCLUSIONS: There is evidence of continuous trabecular bone loss in the paretic tibial distal epiphysis among chronic stroke patients, but it tends to plateau after 2 years of stroke onset. The steady state may have been reached earlier in the hip and tibial diaphysis.

First indications that northern bottlenose whales are sensitive to behavioural disturbance from anthropogenic noise.

Although northern bottlenose whales were the most heavily hunted beaked whale, we have little information about this species in its remote habitat of the North Atlantic Ocean. Underwater anthropogenic noise and disruption of their natural habitat may be major threats, given the sensitivity of other beaked whales to such noise disturbance. We attached dataloggers to 13 northern bottlenose whales and compared their natural sounds and movements to those of one individual exposed to escalating levels of 1-2 kHz upsweep naval sonar signals. At a received sound pressure level (SPL) of 98 dB re 1 µPa, the whale turned to approach the sound source, but at a received SPL of 107 dB re 1 µPa, the whale began moving in an unusually straight course and then made a near 180° turn away from the source, and performed the longest and deepest dive (94 min, 2339 m) recorded for this species. Animal movement parameters differed significantly from baseline for more than 7 h until the tag fell off 33-36 km away. No clicks were emitted during the response period, indicating cessation of normal echolocation-based foraging. A sharp decline in both acoustic and visual detections of conspecifics after exposure suggests other whales in the area responded similarly. Though more data are needed, our results indicate high sensitivity of this species to acoustic disturbance, with consequent risk from marine industrialization and naval activity.

Pregnancy-induced HLA antibodies respond more vigorously after renal transplantation than antibodies induced by prior transplantation.

Acute antibody mediated rejection after HLA-specific antibody incompatible renal transplantation is related to donor specific HLA antibody (DSA) levels. DSA levels may rise sharply after transplant, and aim of this study was to examine changes in DSA levels, particularly according to the primary sensitising event. Changes in 220 HLA specificities in 64 patients over the first 30days after transplantation were evaluated using microbead assays. The greatest increase from pre-treatment to peak DSA levels was seen in pregnancy-stimulated specificities, median (IQR) increase in MFI of 1981 (94-5870). The next highest increase was for those sensitised by transplant with repeat HLA epitope mismatch, at 546 (-308-2698) (p<0.01). The difference was especially marked when the pre-treatment antibody level was low; with pre-treatment MFI <1000, peak level was >1000 in 19/26 (73%) of pregnancy stimulated specificities, compared with 9/29 (31%) for all others (p<0.001). DSA production to specificities stimulated by previous pregnancy was marked, even from very low pre-transplant levels. By contrast, there was a lower rate of antibody resynthesis to specificities repeated from previous transplants, both at antigen and epitope levels.

Corneal collagen crosslinking for keratoconus or corneal ectasia without epithelial debridement.

PURPOSE: Corneal collagen crosslinking (CXL) is a relatively new technique to reduce the progression of keratoconus. The technique can be performed with or without complete debridement of the corneal epithelium. We describe a novel intermediate technique involving mechanical disruption of the epithelium, and evaluate its safety and efficacy. METHODS: The case notes of 128 eyes with progressive keratoconus or iatrogenic corneal ectasia who had undergone CXL using the epithelial disruption technique were retrospectively reviewed. Thin corneas were treated with hypotonic riboflavin. All others were treated with an isotonic solution. Note was made of preoperative and postoperative parameters, including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refraction, endothelial cell count, and corneal tomography. Occurrence of procedure-related complications was recorded. Statistical analyses were performed using the paired sample t-test and Wilcoxon signed-rank test, with a level of P<0.05 being accepted as statistically significant. RESULTS: At 12 months, 41.8% of patients treated with isotonic riboflavin had improved UCVA and 29.7% had improved BSCVA. Only 13.4% lost lines of UCVA and 14.9% lost BSCVA. Of the patients treated with hypotonic riboflavin, at 12 months, 75% demonstrated stability of BSCVA and 25% had stable Kmax. In addition, 25% showed improved visual acuity at 12 months, and 58.3% showed regression of their Kmax. Our rate of short-term complications was comparable to studies using complete epithelial removal. CONCLUSIONS: CXL with epithelial disruption is a safe and effective treatment for keratoconus or iatrogenic corneal ectasia, and may be better tolerated by patients than the epithelium-off technique.

Psychometric properties of dual-task balance assessments for older adults: a systematic review.

BACKGROUND: The ability to maintain balance while simultaneously performing a cognitive task is essential for daily living and has been implicated as a risk factor of falls in older adults. AIMS: To evaluate the evidence related to the psychometric properties of dual-task balance assessments in older adults. METHODS: An extensive literature search of electronic databases was conducted. Articles were included if they evaluated the psychometric properties of dual-task balance assessment tools in older adults. The data were extracted by two independent researchers and confirmed with the principal investigator. The methodology quality of each study was rated by using the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist. RESULTS: Twenty-six articles were included in this systematic review. For dual-task static standing balance assessments, the center of pressure-related parameters (displacement, velocity) and reaction time measurements were reliable but not useful for prediction of falls. For walking balance assessments, the gait outcomes derived generally demonstrated good to excellent reliability (intraclass correlation coefficient >0.75), but their ability to predict falls varied. Outcomes derived from the cognitive tasks and the dual-task cost (dual-task performance minus single-task performance) mostly demonstrated low to fair reliability. The methodological quality of majority of studies was poor to fair, mainly due to small sample size. CONCLUSIONS: Among the dual-task balance assessments examined, the reliability and validity varied. The findings of this review should be useful in guiding the selection of dual-task balance measures in future research.

A low dimensional approach on network characterization.

In many applications, one may need to characterize a given network among a large set of base networks, and these networks are large in size and diverse in structure over the search space. In addition, the characterization algorithms are required to have low volatility and with a small circle of uncertainty. For large datasets, these algorithms are computationally intensive and inefficient. However, under the context of network mining, a major concern of some applications is speed. Hence, we are motivated to develop a fast characterization algorithm, which can be used to quickly construct a graph space for analysis purpose. Our approach is to transform a network characterization measure, commonly formulated based on similarity matrices, into simple vector form signatures. We shall show that the [Formula: see text] similarity matrix can be represented by a dyadic product of two N-dimensional signature vectors; thus the network alignment process, which is usually solved as an assignment problem, can be reduced into a simple alignment problem based on separate signature vectors.