Hypothyroidism Induces Interleukin-1-Dependent Autophagy Mechanism as a Key Mediator of Hippocampal Neuronal Apoptosis and Cognitive Decline in Postnatal Rats

Thyroid hormone (TH) is essential for brain development, and hypothyroidism induces cognitive deficits in children and young adults. However, the participating mechanisms remain less explored. Here, we examined the molecular mechanism, hypothesizing the involvement of a deregulated autophagy and apoptosis pathway in hippocampal neurons that regulate cognitive functions. Therefore, we used a rat model of developmental hypothyroidism, generated through methimazole treatment from gestation until young adulthood. We detected that methimazole stimulated the autophagy mechanism, characterized by increased LC3B-II, Beclin-1, ATG7, and ATG5-12 conjugate and decreased p-mTOR/mTOR and p-ULK1/ULK1 autophagy regulators in the hippocampus of developing and young adult rats. This methimazole-induced hippocampal autophagy could be inhibited by thyroxine treatment. Subsequently, probing the upstream mediators of autophagy revealed an increased hippocampal neuroinflammation, marked by upregulated interleukin (IL)-1alpha and beta and activated microglial marker, Iba1, promoting neuronal IL-1 receptor-1 expression. Hence, IL-1R-antagonist (IL-1Ra), which reduced hippocampal neuronal IL-1R1, also inhibited the enhanced autophagy in hypothyroid rats. We then linked these events with hypothyroidism-induced apoptosis and loss of hippocampal neurons, where we observed that like thyroxine, IL-1Ra and autophagy inhibitor, 3-methyladenine, reduced the cleaved caspase-3 and TUNEL-stained apoptotic neurons and enhanced Nissl-stained neuronal count in methimazole-treated rats. We further related these molecular results with cognition through Y-maze and passive avoidance tests, demonstrating an IL-1Ra and 3-methyladenine-mediated improvement in learning-memory performances of the hypothyroid rats. Taken together, our study enlightens the critical role of neuroinflammation-dependent autophagy mechanism in TH-regulated hippocampal functions, disrupted in developmental hypothyroidism.

Cardiovascular outcomes in patients with type 2 diabetes and reduced eGFR and albuminuria: a REWIND post hoc subgroup analysis

Background/Introduction

Diabetic kidney disease affects up to 40% of people with diabetes and is associated with higher cardiovascular (CV) risk. REWIND was a multicentre, randomised, double-blind, placebo-controlled trial with a primary outcome of first occurrence of the composite endpoint of CV death, nonfatal myocardial infarction, or nonfatal stroke (Major Adverse Cardiovascular Event [MACE]-3). Dulaglutide treatment reduced the incidence of MACE-3 in patients with type 2 diabetes (T2D) with or without established CV disease.

Purpose

This REWIND post hoc subgroup analysis evaluated the effect of dulaglutide on MACE-3 in patients with an eGFR<60 and ≥60 mL/min/1.73m2 and patients with micro-/macro-albuminuria (UACR ≥30 mg/g) or normoalbuminuria (UACR <30 mg/g).

Methods

Eligible patients were those ≥50 years old with T2D who had either a previous CV event or CV risk factors. Patients were randomised (1:1) to dulaglutide 1.5 mg or placebo, both in addition to standard of care. A Cox proportional hazards model with treatment, eGFR subgroup (<60 and ≥60 mL/min/1.73 m2), and treatment by eGFR subgroup interaction was used to analyse time to the first occurrence of MACE-3. These analyses were also conducted for albuminuria subgroups (micro-/macro-albuminuria or normoalbuminuria). Estimates of hazard ratios (HR) with 95% confidence intervals (CI) were calculated for each subgroup.

Results

At baseline, 2,199 of 9,901 patients (22.2%) had an eGFR <60 mL/min/1.73 m2, 2,676 (27.0%) had microalbuminuria, and 791 (8.0%) had macroalbuminuria. This post hoc subgroup analysis showed that dulaglutide treatment was consistently associated with MACE-3 risk reduction in patients with eGFR <60 and ≥60 mL/min/1.73 m2 (HR [95% CI]: 0.93 [0.76–1.13] and 0.86 [0.75–0.99], respectively; interaction p=0.545). Similarly, MACE-3 risk reduction was consistent in patients with micro-/macro-albuminuria or normoalbuminuria (HR [95% CI]: 0.84 [0.72–0.99] and 0.93 [0.79–1.10], respectively; interaction p=0.374).

Conclusions

Regardless of baseline eGFR or albuminuria status, dulaglutide reduces MACE-3 outcomes in patients with T2D and established CV disease or multiple CV risk factors.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Eli Lilly and Company

Abdominal cryptococcosis in dogs and cats: 38 cases (2000-2018)

INTRODUCTION

To report the clinical presentation, laboratory and imaging findings, treatment and outcome of abdominal cryptococcosis in dogs and cats in Australia.

MATERIALS AND METHODS

Canine and feline cases from Australia were retrospectively identified (2000 to 2018) via laboratory and referral centre searches for abdominal cryptococcosis diagnosed by cytology (needle aspirates) or histopathology (biopsy or necropsy) of abdominal organs/tissues. Signalment, presenting complaints, clinical signs, laboratory findings, medical imaging, latex cryptococcal antigen agglutination test (LCAT) titres, treatment and outcome data was collected.

RESULTS

Thirty-eight cases were included (35 dogs, three cats) in the study. Median age of presentation was 2 years for dogs and 6 years for cats. Common presenting complaints included vomiting (23/38), lethargy (19/38) and inappetence/anorexia (15/38). Abdominal ultrasound (25/38 cases) revealed mesenteric and intestinal lesions in most of the cases. On surgical exploration, seven cases had an intestinal lesion associated with an intussusception. Nineteen cases had a pre-treatment LCAT performed, with a median initial titre of 1:2048 (range 1:2 to 65,536). Twenty-four cases (23 dogs, one cat) received treatment, either medical, surgical or both. Median survival time for cases with combined medical and surgical treatment, surgical treatment alone or medical treatment alone was 730, 140 and 561 days, respectively. Eleven remain alive at the time of follow up.

CLINICAL SIGNIFICANCE

Abdominal cryptococcosis although rare should be a considered as a diagnostic possibility in an especially young dog presenting with gastro-intestinal signs. Older dogs can also present with this condition and should not be euthanised based on imaging alone due to the likenesses with neoplasia. With appropriate treatment and monitoring many dogs may have a prolonged survival period and some may be cured.

A practical criterion for focusing of unstained cell samples using a digital holographic microscope

Digital holographic microscopy (DHM) is an important technique that may be used for quantitative phase imaging of unstained biological cell samples. Since the DHM technology is not commonly used in clinics or bioscience research labs, at present there is no well-accepted focusing criterion for unstained samples that users can follow while recording image plane digital holograms of cells. The usual sharpness metrics that are useful for auto-focusing of stained cells do not work well for unstained cells as there is no amplitude contrast. In this work, we report a practical method for estimating the best focus plane for unstained cells in the digital hologram domain. The method is based on an interesting observation that for the best focus plane the fringe pattern associated with individual unstained cells predominantly shows phase modulation effect in the form of bending of fringes and minimal amplitude modulation. This criterion when applied to unstained red blood cells shows that the central dip in the doughnut-like phase profile of cells is maximal in this plane. The proposed methodology is helpful for standardizing the usage of DHM technology across different users and application development efforts. LAY DESCRIPTION: Digital holographic microscopy (DHM) is slowly but steadily becoming an important microscopy modality and gaining acceptability for basic bio-science research as well as clinical usage. One of the important features of DHM is that it allows users to perform quantitative imaging of unstained transparent cells. Instead of using dyes or fluorescent labelling, DHM systems use quantitative phase as a contrast mechanism which depends on the natural refractive index variation within the cell samples. Since minimal wet lab processing is required in order to image cell samples with a DHM, cells can be imaged in their natural state. While DHM is gaining popularity among users, the imaging protocols across the labs or users need to be standardized in order to make sure that the same quantitative phase parameters are used for tasks such as quantitative phased based cell classification. One of the important operational tasks for any microscopy work is to focus the sample under study. While focusing comes naturally to users of brightfield microscopes based on image contrast, the focusing is not straightforward when samples are unstained so that they do not offer any amplitude contrast. When performing quantitative phase imaging, defocus can actually change the phase profile of the cell due to near-zone (Fresnel) diffraction effects. So unless a standardized focusing methodology is used, it will be difficult for multiple DHM users (potentially at different sites) to agree on quantitative results out of their phase images. DHM literature has prior works which perform numerical focusing of recovered complex wave-field in the hologram plane to find the best focus plane. However such methods are not user friendly and do not allow user the same focusing experience as in a brightfield microscope. The numerical focusing is therefore a reasonably good method for an optics researcher but not necessarily so for a microscopy technician looking at cell samples with a DHM system in a clinical setting. The present work provides a simple focusing criterion for unstained samples that works directly in the hologram domain. The technique is based on an interesting observation that the when an unstained cell sample is in the best-focus plane, its corresponding hologram (or fringe pattern) predominantly shows phase modulation manifested by bending of fringes at the location of the cell. This criterion can be converted into a simple numerical method as we have used to find the best-focus plane using a stack of through focus holograms. We believe that the technique can be used manually by visually observing the holograms or can be converted to an auto-focus algorithm for a motorized DHM system.

Rigidity controls human desmoplastic matrix anisotropy to enable pancreatic cancer cell spread via extracellular signal-regulated kinase 2

It is predicted that pancreatic ductal adenocarcinoma (PDAC) will become the second most lethal cancer in the US by 2030. PDAC includes a fibrous-like stroma, desmoplasia, encompassing most of the tumor mass, which is produced by cancer-associated fibroblasts (CAFs) and includes their cell-derived extracellular matrices (CDMs). Since elimination of desmoplasia has proven detrimental to patients, CDM reprogramming, as opposed to stromal ablation, is therapeutically desirable. Hence, efforts are being made to harness desmoplasia's anti-tumor functions. We conducted biomechanical manipulations, using variations of pathological and physiological substrates in vitro, to culture patient-harvested CAFs and generate CDMs that restrict PDAC growth and spread. We posited that extrinsic modulation of the environment, via substrate rigidity, influences CAF's cell-intrinsic forces affecting CDM production. Substrates used were polyacrylamide gels of physiological (~1.5 kPa) or pathological (~7 kPa) stiffnesses. Results showed that physiological substrates influenced CAFs to generate CDMs similar to normal/control fibroblasts. We found CDMs to be softer than the corresponding underlying substrates, and CDM fiber anisotropy (i.e., alignment) to be biphasic and informed via substrate-imparted morphological CAF aspect ratios. The biphasic nature of CDM fiber anisotropy was mathematically modeled and proposed a correlation between CAF aspect ratios and CDM alignment; regulated by extrinsic and intrinsic forces to conserve minimal free energy. Biomechanical manipulation of CDMs, generated on physiologically soft substrates, leads to reduction in nuclear translocation of pERK1/2 in KRAS mutated pancreatic cells. ERK2 was found essential for CDM-regulated tumor cell spread. In vitro findings correlated with in vivo observations; nuclear pERK1/2 is significantly high in human PDAC samples. The study suggests that altering underlying substrates enable CAFs to remodel CDMs and restrict pancreatic cancer cell spread in an ERK2 dependent manner.

Rheumatoid Keratolysis: A Series of 40 Eyes

PURPOSE

Rheumatoid keratolysis (RK) is a rare but a serious cause of ocular morbidity in rheumatoid patients. The aim of this study was to analyze the presenting features, the subsequent treatment, and the outcome of patients with RK in the authors' department.

METHODS

A retrospective study was undertaken of all patients with a diagnosis of RK at Bristol Eye Hospital between January 1987 and June 2002.

RESULTS

Forty eyes of 38 patients were identified in total. The mean age at presentation was 70 years. The mean duration of rheumatoid arthritis at presentation was 15 years. Most (22, 55%) ulcers were peripheral. Three patients (8%) developed RK within a month of cataract surgery. Out of the 19 patients who did not have a further RK, 11 were immunosuppressed. A total of 37 grafts were performed on 26 eyes. Twenty-two grafts (59%) failed. Immunosuppression increased the chance of anatomical success following penetrating keratoplasty. Infection was identified as a cause of graft failure for immunosuppressed patients in the postoperative period. Nine patients had reversible side effects from immunosuppressant treatment. Four eyes (10%) had to be surgically removed and a further 10 (25%) had severe visual loss (visual acuity less than 6/60). Eleven of the 38 patients subsequently died (29% mortality).

CONCLUSIONS

Although the visual prognosis is often poor, surgical preservation of the eye can be achieved by penetrating keratoplasty and systemic immunosuppression. With careful observation and regular monitoring, immunosuppressive medication appears to be safely tolerated in this group of patients.

Binder-free Sn–Si heterostructure films for high capacity Li-ion batteries

This study fabricated and demonstrated a functional, stable electrode structure for a high capacity Li-ion battery (LIB) anode. Effective performance is assessed in terms of reversible lithiation for a significant number of charge–discharge cycles to 80% of initial capacity. The materials selected for this study are silicon and tin and are co-deposited using an advanced manufacturing technique (plasma-enhanced chemical vapour deposition), shown to be a scalable process that can facilitate film growth on 3D substrates. Uniform and hybrid crystalline–amorphous Si nanowire (SiNW) growth is achieved via a vapour–liquid–solid mechanism using a Sn metal catalyst. SiNWs of less than 300 nm diameter are known to be less susceptible to fracture and when grown this way have direct electrical conductivity to the current collector, with sufficient room for expansion. Electrochemical characterisation shows stable cycling at capacities of 1400 mA h g⁻¹ (>4 × the capacity limit of graphite). This hybrid system demonstrates promising electrochemical performance, can be grown at large scale and has also been successfully grown on flexible carbon paper current collectors. These findings will have impact on the development of flexible batteries and wearable energy storage.

This study fabricated and demonstrated a functional, stable electrode structure for a high capacity Li-ion battery (LIB) anode.

Subclinical cardiovascular disease in patients with chronic obstructive pulmonary disease: a systematic review

BACKGROUND

Cardiovascular disease (CVD) accounts for a significant portion of deaths in patients with COPD; however, evidence for early detection strategies for CVD in this population remain limited. Our paper aims to summarize existing data regarding subclinical CVD in patients with COPD with a view to identifying screening strategies in these patients.

METHODS

A systematic review of published literature was conducted for studies examining the relationship of COPD and markers of subclinical disease such as coronary artery calcification (CAC), carotid intima media thickness (cIMT), endothelial dysfunction, arterial stiffness as measured by pulse wave velocity (PWV) and augmentation indices (AIx). Both MEDLINE and EMBASE databases were searched till October 2015.

RESULTS

A total of 22 studies were included in the review. Compared with control subjects, patients with COPD had significantly higher cIMT (SMD 0.53, 95% CI 0.16-0.90), PWV (SMD 0.91, 95% CI 0.67-1.16) and AIx (SMD 0.86, 95% CI 0.52-1.19). Additionally, an overall higher prevalence of subclinical CVD as assessed by CAC, ABI and FMD was noted in our review.

CONCLUSION

Although our findings need further evaluation in prospective studies, our review presents significant evidence in support of increased subclinical CVD burden in COPD patients independent of smoking status. Further large-scale case-control studies are required to highlight the significance of subclinical CVD screening in COPD patients.

Antimicrobial Prescribing in Dogs and Cats in Australia: Results of the Australasian Infectious Disease Advisory Panel Survey

Background

Investigations of antimicrobial use in companion animals are limited. With the growing recognition of the need for improved antimicrobial stewardship, there is urgent need for more detailed understanding of the patterns of antimicrobial use in this sector.

Objectives

To investigate antimicrobial use for medical and surgical conditions in dogs and cats by Australian veterinarians.

Methods

A cross‐sectional study was performed over 4 months in 2011. Respondents were asked about their choices of antimicrobials for empirical therapy of diseases in dogs and cats, duration of therapy, and selection based on culture and susceptibility testing, for common conditions framed as case scenarios: 11 medical, 2 surgical, and 8 dermatological.

Results

A total of 892 of the 1,029 members of the Australian veterinary profession that completed the survey satisfied the selection criteria. Empirical antimicrobial therapy was more common for acute conditions (76%) than chronic conditions (24%). Overall, the most common antimicrobial classes were potentiated aminopenicillins (36%), fluoroquinolones (15%), first‐ and second‐generation cephalosporins (14%), and tetracyclines (11%). Third‐generation cephalosporins were more frequently used in cats (16%) compared to dogs (2%). Agreement with Australasian Infectious Disease Advisory Panel (AIDAP) guidelines (generated subsequently) was variable ranging from 0 to 69% between conditions.

Conclusions and Clinical Importance

Choice of antimicrobials by Australian veterinary practitioners was generally appropriate, with relatively low use of drugs of high importance, except for the empirical use of fluoroquinolones in dogs, particularly for otitis externa and 3rd‐generation cephalosporins in cats. Future surveys will determine whether introduction of the 2013 AIDAP therapeutic guidelines has influenced prescribing habits.

Abstract P6-12-05: Targeting estrogen receptor mutations for treatment of endocrine therapy resistance in breast cancer

This abstract was withdrawn by the authors.

Epidemiological investigation of grass seed foreign body-related disease in dogs of the Riverina District of rural Australia

OBJECTIVE

To characterise disease presentations caused by grass seed foreign body-related disease (GSFBD) in dogs, identify predisposing risk factors and suggest effective prevention strategies.

METHODS

A retrospective, case-control, telephone survey was conducted to obtain information on GSFBD in dogs from the Riverina district of New South Wales (NSW). Additionally, retrospective case records were obtained from Wagga Wagga Veterinary Hospital and Charles Sturt University Veterinary Teaching Hospital over the period July 2006 to October 2011. Signalment, history, investigative strategies, location and severity of lesion(s), cost of therapy, length of hospitalisation, recurrence rate and microbiology data were recorded.

RESULTS

Cases (473 dogs) meeting stringent inclusion criteria were identified. GSFBD comprised 2.0% of hospital presentations. Breeds with high-density coats were overrepresented. Otitis externa was the most common manifestation of GSFBD in the general practice (47%). In the referral practice pyothorax was the most common entity (34%). In both practices the range of clinical manifestations was broad, including a small number of dogs with catastrophic intracranial disease. Univariable and multivariable logistic regression analyses demonstrated dogs with GSFBD had 3-fold greater odds of having medium coats than short coats and 5-fold less odds of being groomed.

CONCLUSIONS AND CLINICAL RELEVANCE

Grass seeds are a major cause of disease in the dogs of south-west rural NSW, with presentations ranging from mild lameness to severe neurological disease. Some protection from GSFBD was achieved with frequent grooming. Clipping or coat searching without grooming was ineffective as a prevention strategy.