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1.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Article in English | MEDLINE | ID: mdl-35165147

ABSTRACT

Dravet syndrome (DS) is one of the most severe childhood epilepsies, characterized by intractable seizures and comorbidities including cognitive and social dysfunction and high premature mortality. DS is mainly caused by loss-of-function mutations in the Scn1a gene encoding Nav1.1 that is predominantly expressed in inhibitory parvalbumin-containing (PV) interneurons. Decreased Nav1.1 impairs PV cell function, contributing to DS phenotypes. Effective pharmacological therapy that targets defective PV interneurons is not available. The known role of brain-derived neurotrophic factor (BDNF) in the development and maintenance of interneurons, together with our previous results showing improved PV interneuronal function and antiepileptogenic effects of a TrkB receptor agonist in a posttraumatic epilepsy model, led to the hypothesis that early treatment with a TrkB receptor agonist might prevent or reduce seizure activity in DS mice. To test this hypothesis, we treated DS mice with LM22A-4 (LM), a partial agonist at the BDNF TrkB receptor, for 7 d starting at postnatal day 13 (P13), before the onset of spontaneous seizures. Results from immunohistochemistry, Western blot, whole-cell patch-clamp recording, and in vivo seizure monitoring showed that LM treatment increased the number of perisomatic PV interneuronal synapses around cortical pyramidal cells in layer V, upregulated Nav1.1 in PV neurons, increased inhibitory synaptic transmission, and decreased seizures and the mortality rate in DS mice. The results suggest that early treatment with a partial TrkB receptor agonist may be a promising therapeutic approach to enhance PV interneuron function and reduce epileptogenesis and premature death in DS.


Subject(s)
Benzamides/therapeutic use , Epilepsies, Myoclonic/genetics , Epilepsies, Myoclonic/mortality , Receptor, trkB/agonists , Receptor, trkB/metabolism , Seizures/etiology , Seizures/genetics , Animals , Epilepsies, Myoclonic/metabolism , Gene Expression Regulation/drug effects , Mice , NAV1.1 Voltage-Gated Sodium Channel/genetics , NAV1.1 Voltage-Gated Sodium Channel/metabolism , Neocortex/cytology , Pyramidal Cells/metabolism , Receptor, trkB/genetics
2.
BMC Biol ; 21(1): 153, 2023 07 10.
Article in English | MEDLINE | ID: mdl-37430246

ABSTRACT

BACKGROUND: The standard evolutionary theory of ageing proposes that ageing occurs because of a trade-off between reproduction and longevity. Eusocial insect queens exhibit positive fecundity-longevity associations and so have been suggested to be counter-examples through not expressing costs of reproduction and through remodelling conserved genetic and endocrine networks regulating ageing and reproduction. If so, eusocial evolution from solitary ancestors with negative fecundity-longevity associations must have involved a stage at which costs of reproduction were suppressed and fecundity and longevity became positively associated. Using the bumblebee (Bombus terrestris), we experimentally tested whether queens in annual eusocial insects at an intermediate level of eusocial complexity experience costs of reproduction, and, using mRNA-seq, the extent to which they exhibit a remodelling of relevant genetic and endocrine networks. Specifically, we tested whether costs of reproduction are present but latent, or whether a remodelling of relevant genetic and endocrine networks has already occurred allowing queens to reproduce without costs. RESULTS: We experimentally increased queens' costs of reproduction by removing their eggs, which caused queens to increase their egg-laying rate. Treatment queens had significantly reduced longevity relative to control queens whose egg-laying rate was not increased. Reduced longevity in treatment queens was not caused by increased worker-to-queen aggression or by increased overall activity in queens. In addition, treatment and control queens differed in age-related gene expression based on mRNA-seq in both their overall expression profiles and the expression of ageing-related genes. Remarkably, these differences appeared to occur principally with respect to relative age, not chronological age. CONCLUSIONS: This study represents the first simultaneously phenotypic and transcriptomic experimental test for a longevity cost of reproduction in eusocial insect queens. The results support the occurrence of costs of reproduction in annual eusocial insects of intermediate social complexity and suggest that reproductive costs are present but latent in queens of such species, i.e. that these queens exhibit condition-dependent positive fecundity-longevity associations. They also raise the possibility that a partial remodelling of genetic and endocrine networks underpinning ageing may have occurred in intermediately eusocial species such that, in unmanipulated conditions, age-related gene expression depends more on chronological than relative age.


Subject(s)
Fertility , Reproduction , Bees/genetics , Animals , Aging , Longevity , RNA, Messenger
3.
Neurobiol Dis ; 176: 105934, 2023 01.
Article in English | MEDLINE | ID: mdl-36442714

ABSTRACT

Status epilepticus (SE) is a life-threatening emergency that can result in de novo development or worsening of epilepsy. We tested the hypothesis that the aberrant cortical output during neocortical focal status epilepticus (FSE) would induce structural and functional changes in the thalamus that might contribute to hyperexcitability in the thalamocortical circuit. We induced neocortical FSE by unilateral epidural application of convulsant drugs to the somatosensory cortex of anesthetized mice of both sexes. The resulting focal EEG ictal episodes were associated with behavioral seizures consisting of contralateral focal myoclonic activity and persisted for 2-3 h. Ten and 30 days later, brains were processed for either immunohistochemistry (IHC) or in vitro slice recordings. Sections from the center of the thalamic reticular nucleus (nRT, see methods), the ventral posterolateral nucleus (VPL), and the ventral posteromedial nucleus (VPM) from the ventrobasal nucleus (VB) were used to measure density of NeuN-immunoreactive neurons, GFAP-reactive astrocytes, and colocalized areas for VGLUT1 + PSD95- and VGLUT2 + PSD95-IR, presumptive excitatory synapses of cortical and thalamic origins. Whole-cell voltage-clamp recordings were used to measure spontaneous EPSC frequency in these nuclei. We found that the nRT showed no decrease in numbers of neurons or evidence of reactive astrogliosis. In contrast, there were increases in GFAP-IR and decreased neuronal counts of NeuN positive cells in VB. Dual IHC for VGLUT1-PSD95 and VGLUT2-PSD95 in VB showed increased numbers of excitatory synapses, likely of both thalamic and cortical origins. The frequency, but not the amplitude of sEPSCs was increased in nRT and VB neurons. SIGNIFICANCE STATEMENT: Previous reports have shown that prolonged neocortical seizures can induce injury to downstream targets that might contribute to long-term consequences of FSE. Effects of FSE in thalamic structures may disrupt normal thalamo-cortical network functions and contribute to behavioral abnormalities and post-SE epileptogenesis. Our results show that a single episode of focal neocortical SE in vivo has chronic consequences including cell loss in VB nuclei and increased excitatory connectivity in intra-thalamic and cortico-thalamic networks. Additional experiments will assess the functional consequences of these alterations and approaches to mitigate cell loss and alterations in synaptic connectivity.


Subject(s)
Neocortex , Status Epilepticus , Male , Female , Mice , Animals , Thalamus , Neurons , Thalamic Nuclei/physiology , Seizures
4.
Am J Kidney Dis ; 82(2): 179-188, 2023 08.
Article in English | MEDLINE | ID: mdl-36740038

ABSTRACT

RATIONALE & OBJECTIVE: Available decision aids for patients about treatment of advanced chronic kidney disease (CKD) often lack information on conservative kidney management (CKM). We assessed the feasibility and acceptability of a decision aid on CKM among patients with advanced CKD and their family members. STUDY DESIGN: Randomized pilot trial. SETTING & PARTICIPANTS: Patients aged≥75 years with stage 4 or 5 CKD and their family members at 4 medical centers in the greater Seattle area between August 2020 and December 2021. INTERVENTIONS: Usual care with or without a decision aid on CKM. OUTCOME: Acceptability was assessed by attrition rates between the initial study visit (T1) and the 3-month follow-up evaluation (T3). The primary outcome and measure of feasibility was the proportion of participants who discussed CKM with a health care provider between T1 and T3. RESULTS: We randomized 92 patients of whom 86 (55.8% male; age 82±6 years; 82.6% White) completed T1-42 in the usual care arm and 44 in the usual care plus decision aid arm-and 56 family members of whom 53 (18.9% male; age 71±11 years; 86.8% White) completed T1-20 in usual care arm and 33 in the usual care plus decisions aid arm. The attrition rates were 21% versus 21% (P=1.0) for patients, and 10% versus 18% (P=0.46) for family members in the usual care versus usual care plus decisions aid arms. Receipt of the decision aid significantly increased discussion of CKM with a health care provider for patients (26.4% vs 3.0%, P=0.007) and family members (26.9% vs 0, P=0.02). LIMITATIONS: Possible limited generalizability because participants were a relatively homogenous group. The decision aid focuses on CKM and may be less applicable to those with limited knowledge of kidney replacement therapies. CONCLUSIONS: A CKM decision aid was feasible and acceptable, and increased discussion of this treatment option with health care providers. This aid may serve as a useful adjunct to the currently available educational tools on treatments for advanced CKD. FUNDING: Grant from a not-for-profit entity (National Palliative Care Research Center). TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT04919941.


Subject(s)
Decision Support Techniques , Renal Insufficiency, Chronic , Humans , Male , Female , Pilot Projects , Renal Insufficiency, Chronic/therapy , Palliative Care , Kidney
5.
Am J Kidney Dis ; 82(3): 311-321.e1, 2023 09.
Article in English | MEDLINE | ID: mdl-37178093

ABSTRACT

RATIONALE & OBJECTIVE: Acute kidney injury (AKI) is a heterogeneous clinical syndrome with varying causes, pathophysiology, and outcomes. We incorporated plasma and urine biomarker measurements to identify AKI subgroups (subphenotypes) more tightly linked to underlying pathophysiology and long-term clinical outcomes. STUDY DESIGN: Multicenter cohort study. SETTING & PARTICIPANTS: 769 hospitalized adults with AKI matched with 769 without AKI, enrolled from December 2009 to February 2015 in the ASSESS-AKI Study. PREDICTORS: 29 clinical, plasma, and urinary biomarker parameters used to identify AKI subphenotypes. OUTCOME: Composite of major adverse kidney events (MAKE) with a median follow-up period of 4.7 years. ANALYTICAL APPROACH: Latent class analysis (LCA) and k-means clustering were applied to 29 clinical, plasma, and urinary biomarker parameters. Associations between AKI subphenotypes and MAKE were analyzed using Kaplan-Meier curves and Cox proportional hazard models. RESULTS: Among 769 AKI patients both LCA and k-means identified 2 distinct AKI subphenotypes (classes 1 and 2). The long-term risk for MAKE was higher with class 2 (adjusted HR, 1.41 [95% CI, 1.08-1.84]; P=0.01) compared with class 1, adjusting for demographics, hospital level factors, and KDIGO stage of AKI. The higher risk of MAKE among class 2 was explained by a higher risk of long-term chronic kidney disease progression and dialysis. The top variables that were different between classes 1 and 2 included plasma and urinary biomarkers of inflammation and epithelial cell injury; serum creatinine ranked 20th out of the 29 variables for differentiating classes. LIMITATIONS: A replication cohort with simultaneously collected blood and urine sampling in hospitalized adults with AKI and long-term outcomes was unavailable. CONCLUSIONS: We identify 2 molecularly distinct AKI subphenotypes with differing risk of long-term outcomes, independent of the current criteria to risk stratify AKI. Future identification of AKI subphenotypes may facilitate linking therapies to underlying pathophysiology to prevent long-term sequalae after AKI. PLAIN-LANGUAGE SUMMARY: Acute kidney injury (AKI) occurs commonly in hospitalized patients and is associated with high morbidity and mortality. The AKI definition lumps many different types of AKI together, but subgroups of AKI may be more tightly linked to the underlying biology and clinical outcomes. We used 29 different clinical, blood, and urinary biomarkers and applied 2 different statistical algorithms to identify AKI subtypes and their association with long-term outcomes. Both clustering algorithms identified 2 AKI subtypes with different risk of chronic kidney disease, independent of the serum creatinine concentrations (the current gold standard to determine severity of AKI). Identification of AKI subtypes may facilitate linking therapies to underlying biology to prevent long-term consequences after AKI.


Subject(s)
Acute Kidney Injury , Renal Insufficiency, Chronic , Adult , Humans , Cohort Studies , Creatinine , Biomarkers , Acute Kidney Injury/etiology , Renal Insufficiency, Chronic/complications
6.
Liver Int ; 43(1): 60-68, 2023 01.
Article in English | MEDLINE | ID: mdl-36050826

ABSTRACT

BACKGROUND AND AIMS: Significant barriers exist with hepatitis B (HBV) case detection and effective linkage to care (LTC). The emergency department (ED) is a unique healthcare interaction where hepatitis screening and LTC could be achieved. We examined the efficacy and utility of automated ED HBV screening for Overseas Born (OB) patients. METHODS: A novel-automated hepatitis screening service "SEARCH" (Screening Emergency Admissions at Risk of Chronic Hepatitis) was piloted at a metropolitan hospital. A retrospective and comparative analysis of hepatitis testing during the SEARCH pilot compared to a period of routine testing was conducted. RESULTS: During the SEARCH pilot, 4778 OB patients were tested for HBV (86% of eligible patient presentations), compared with 1.9% of eligible patients during a control period of clinician-initiated testing. SEARCH detected 108 (2.3%) hepatitis B surface antigen positive patients including 20 (19%) in whom the diagnosis was new. Among 88 patients with known HBV, 57% were receiving medical care, 33% had become lost to follow-up and 10% had never received HBV care. Overall, 30/88 (34%) patients with known HBV were receiving complete guideline-based care prior to re-engagement via SEARCH. Following SEARCH, LTC was successful achieved in 48/58 (83%) unlinked patients and 19 patients were commenced on anti-viral therapy. New diagnoses of cirrhosis and hepatocellular carcinoma were made in five and one patient(s) respectively. CONCLUSIONS: Automated ED screening of OB patients is effective in HBV diagnosis, re-diagnosis and LTC. Prior to SEARCH, the majority of patients were not receiving guideline-based care.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Liver Neoplasms , Humans , Retrospective Studies , Mass Screening , Hepatitis B/diagnosis , Hepatitis, Chronic , Hepatitis B virus , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/epidemiology , Hepatitis B Surface Antigens
7.
J Gastroenterol Hepatol ; 38(8): 1211-1217, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37263779

ABSTRACT

Alcohol consumption is a major cause of cirrhosis and hepatocellular carcinoma (HCC). The prevalence of alcohol-associated hepatocellular carcinoma (aHCC) varies worldwide but is highest in Eastern Europe. Alcohol is the second fastest-growing cause of age-standardized liver cancer mortality with tumors more often diagnosed outside surveillance protocols and at a more advanced stage. Risk factors for aHCC include greater amounts of alcohol consumption, sex, and certain genetic polymorphisms. Smoking, concomitant liver disease, obesity, and diabetes act synergistically in increasing the risk of HCC in alcohol-associated liver disease. Alcohol-related hepatocarcinogenesis results from the complex interactions of several mechanistic pathways. Although not completely understood, underlying mechanisms include acetaldehyde-related hepatotoxicity, oxidative stress, activation of the innate immune system, and alterations of the host microbiome.


Subject(s)
Carcinoma, Hepatocellular , Liver Diseases, Alcoholic , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/epidemiology , Carcinoma, Hepatocellular/etiology , Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/epidemiology , Liver Neoplasms/etiology , Liver Neoplasms/diagnosis , Ethanol , Risk Factors , Liver Diseases, Alcoholic/epidemiology , Liver Diseases, Alcoholic/complications , Alcohol Drinking/adverse effects , Carcinogenesis/genetics
8.
Kidney Int ; 101(5): 1017-1026, 2022 05.
Article in English | MEDLINE | ID: mdl-35227689

ABSTRACT

Collapsing glomerulopathy is a histologically distinct variant of focal and segmental glomerulosclerosis that presents with heavy proteinuria and portends a poor prognosis. Collapsing glomerulopathy can be triggered by viral infections such as HIV or SARS-CoV-2. Transcriptional profiling of collapsing glomerulopathy lesions is difficult since only a few glomeruli may exhibit this histology within a kidney biopsy and the mechanisms driving this heterogeneity are unknown. Therefore, we used recently developed digital spatial profiling (DSP) technology which permits quantification of mRNA at the level of individual glomeruli. Using DSP, we profiled 1,852 transcripts in glomeruli isolated from formalin fixed paraffin embedded sections from HIV or SARS-CoV-2-infected patients with biopsy-confirmed collapsing glomerulopathy and used normal biopsy sections as controls. Even though glomeruli with collapsing features appeared histologically similar across both groups of patients by light microscopy, the increased resolution of DSP uncovered intra- and inter-patient heterogeneity in glomerular transcriptional profiles that were missed in early laser capture microdissection studies of pooled glomeruli. Focused validation using immunohistochemistry and RNA in situ hybridization showed good concordance with DSP results. Thus, DSP represents a powerful method to dissect transcriptional programs of pathologically discernible kidney lesions.


Subject(s)
COVID-19 , Glomerulosclerosis, Focal Segmental , HIV Infections , Kidney Diseases , Female , Glomerulosclerosis, Focal Segmental/pathology , Humans , Kidney Diseases/genetics , Kidney Diseases/pathology , Kidney Glomerulus/pathology , Male , SARS-CoV-2
9.
J Gastroenterol Hepatol ; 37(11): 2173-2181, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36031345

ABSTRACT

BACKGROUND AND AIM: The exact place for selective internal radiation therapy (SIRT) in the therapeutic algorithm for hepatocellular carcinoma (HCC) is debated. There are limited data on its indications, efficacy, and safety in Australia. METHODS: We performed a multicenter retrospective cohort study of patients undergoing SIRT for HCC in all Sydney hospitals between 2005 and 2019. The primary outcome was overall survival. Secondary outcomes were progression-free survival and adverse events. RESULTS: During the study period, 156 patients underwent SIRT across 10 institutions (mean age 67 years, 81% male). SIRT use progressively increased from 2005 (n = 2), peaking in 2017 (n = 42) before declining (2019: n = 21). Barcelona Clinic Liver Cancer stages at treatment were A (13%), B (33%), C (52%), and D (2%). Forty-four (28%) patients had tumor thrombus. After a median follow-up of 13.9 months, there were 117 deaths. Median overall survival was 15 months (95% confidence interval 11-19). Independent predictors of mortality on multivariable analysis were extent of liver involvement, Barcelona Clinic Liver Cancer stage, baseline ascites, alpha fetoprotein, and model for end-stage liver disease score. Median progression-free survival was 6.0 months (95% confidence interval 5.1-6.9 months). Following SIRT, 11% of patients were downstaged to curative therapy. SIRT-related complications occurred in 17%: radioembolization-induced liver disease (11%), pneumonitis (3%), gastrointestinal ulceration, and cholecystitis (1% each). Baseline ascites predicted for radioembolization-induced liver disease. CONCLUSION: We present the largest Australian SIRT cohort for HCC. We have identified several factors associated with a poor outcome following SIRT. Patients with early-stage disease had the best survival with some being downstaged to curative therapy.


Subject(s)
Carcinoma, Hepatocellular , End Stage Liver Disease , Liver Neoplasms , Sirtuins , Humans , Male , Aged , Female , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Yttrium Radioisotopes , Cohort Studies , Retrospective Studies , Ascites/drug therapy , Australia/epidemiology , Severity of Illness Index , Sirtuins/therapeutic use , Treatment Outcome
10.
Proc Natl Acad Sci U S A ; 116(7): 2767-2773, 2019 02 12.
Article in English | MEDLINE | ID: mdl-30692254

ABSTRACT

Arabidopsis thaliana accessions are universally resistant at the adult leaf stage to white rust (Albugo candida) races that infect the crop species Brassica juncea and Brassica oleracea We used transgressive segregation in recombinant inbred lines to test if this apparent species-wide (nonhost) resistance in A. thaliana is due to natural pyramiding of multiple Resistance (R) genes. We screened 593 inbred lines from an Arabidopsis multiparent advanced generation intercross (MAGIC) mapping population, derived from 19 resistant parental accessions, and identified two transgressive segregants that are susceptible to the pathogen. These were crossed to each MAGIC parent, and analysis of resulting F2 progeny followed by positional cloning showed that resistance to an isolate of A. candida race 2 (Ac2V) can be explained in each accession by at least one of four genes encoding nucleotide-binding, leucine-rich repeat (NLR) immune receptors. An additional gene was identified that confers resistance to an isolate of A. candida race 9 (AcBoT) that infects B. oleracea Thus, effector-triggered immunity conferred by distinct NLR-encoding genes in multiple A. thaliana accessions provides species-wide resistance to these crop pathogens.


Subject(s)
Arabidopsis/immunology , Brassica/microbiology , Oomycetes/pathogenicity , Plant Diseases/immunology , Arabidopsis/genetics , Arabidopsis/microbiology , Arabidopsis Proteins/genetics , Gene Expression Regulation, Plant , Genes, Plant , Haplotypes , Immunity, Innate , Plant Diseases/microbiology
11.
J Am Soc Nephrol ; 32(5): 1200-1209, 2021 05 03.
Article in English | MEDLINE | ID: mdl-33692088

ABSTRACT

BACKGROUND: BP is an important modifiable risk factor for cardiovascular events and CKD progression in middle-aged or older adults with CKD. However, studies describing the relationship between BP with outcomes in young adults with CKD are limited. METHODS: In an observational study, we focused on 317 young adults (aged 21-40 years) with mild to moderate CKD enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study. Exposures included baseline systolic BP evaluated continuously (per 10 mm Hg increase) and in categories (<120, 120-129, and ≥130 mm Hg). Primary outcomes included cardiovascular events (heart failure, myocardial infarction, stroke, or all-cause death) and CKD progression (50% decline of eGFR or ESKD). We used Cox proportional hazard models to test associations between baseline systolic BP with cardiovascular events and CKD progression. RESULTS: Cardiovascular events occurred in 52 participants and 161 had CKD progression during median follow-up times of 11.3 years and 4.1 years, respectively. Among those with baseline systolic BP ≥130 mm Hg, 3%/yr developed heart failure, 20%/yr had CKD progression, and 2%/yr died. In fully adjusted models, baseline systolic BP ≥130 mm Hg (versus systolic BP<120 mm Hg) was significantly associated with cardiovascular events or death (hazard ratio [HR], 2.13; 95% confidence interval [95% CI], 1.05 to 4.32) and CKD progression (HR, 1.68; 95% CI, 1.10 to 2.58). CONCLUSIONS: Among young adults with CKD, higher systolic BP is significantly associated with a greater risk of cardiovascular events and CKD progression. Trials of BP management are needed to test targets and treatment strategies specifically in young adults with CKD.


Subject(s)
Blood Pressure/physiology , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/physiopathology , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/physiopathology , Adult , Age Factors , Cohort Studies , Disease Progression , Female , Glomerular Filtration Rate , Humans , Male , Proportional Hazards Models , Risk Factors , Young Adult
12.
J Viral Hepat ; 28(1): 121-128, 2021 01.
Article in English | MEDLINE | ID: mdl-32869904

ABSTRACT

The World Health Organization has set ambitious viral hepatitis elimination targets; however, difficulties in identifying and engaging patients remain. The emergency visit is an opportunity for enhanced linkage to care (LTC). We assessed the effectiveness of an automated Emergency Department (ED) screening service in identifying patients with hepatitis C (HCV) and achieving LTC. A retrospective evaluation was undertaken, analysing the first 5000 patients screened through an automatic Australian service termed 'Screening Emergency Admissions at Risk of Chronic Hepatitis' (SEARCH). Screening was performed for those recommended in the Australian national testing policy, specifically overseas born (OB) and Aboriginal or Torres Strait Islanders (ATSI). Healthcare worker education, patient information materials and opt-out informed consent were used to test sera already collected for biochemistry assays. 5000 of 5801 (86.2%) consecutive eligible patients were screened (OB: 4778, ATSI: 222) from 14 093 ED presentations. HCV antibody was positive in 181 patients (3.6%); 51 (1.0%) were HCV RNA positive. Of 51 HCV RNA-positive patients, 12 were new diagnoses, 32 were 're-diagnoses' (aware but lost to follow-up [LTFU]), and 7 were previously known but treatment contraindicated. LTC was successful in 38 viraemic patients (7 deceased, 4 LTFU, 1 treatment ineligible and 1 declined). Of RNA-negative patients, 75 were previously treated and 49 had presumed spontaneous clearance. Opt-out consent was acceptable to all patients and staff involved. ED screening can lead to additional diagnosing and 're-diagnosing' of HCV, with high rates of LTC. Opt-out consent and automation removed major obstacles to testing.


Subject(s)
Hepatitis C, Chronic , Hepatitis C , Australia/epidemiology , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/epidemiology , Humans , Mass Screening , Retrospective Studies
13.
Mol Ecol ; 30(3): 718-735, 2021 02.
Article in English | MEDLINE | ID: mdl-33238067

ABSTRACT

The queen-worker caste system of eusocial insects represents a prime example of developmental polyphenism (environmentally-induced phenotypic polymorphism) and is intrinsic to the evolution of advanced eusociality. However, the comparative molecular basis of larval caste determination and subsequent differentiation in the eusocial Hymenoptera remains poorly known. To address this issue within bees, we profiled caste-associated gene expression in female larvae of the intermediately eusocial bumblebee Bombus terrestris. In B. terrestris, female larvae experience a queen-dependent period during which their caste fate as adults is determined followed by a nutrition-sensitive period also potentially affecting caste fate but for which the evidence is weaker. We used mRNA-seq and qRT-PCR validation to isolate genes differentially expressed between each caste pathway in larvae at developmental stages before and after each of these periods. We show that differences in gene expression between caste pathways are small in totipotent larvae, then peak after the queen-dependent period. Relatively few novel (i.e., taxonomically-restricted) genes were differentially expressed between castes, though novel genes were significantly enriched in late-instar larvae in the worker pathway. We compared sets of caste-associated genes in B. terrestris with those reported from the advanced eusocial honeybee, Apis mellifera, and found significant but relatively low levels of overlap of gene lists between the two species. These results suggest both the existence of low numbers of shared toolkit genes and substantial divergence in caste-associated genes between Bombus and the advanced eusocial Apis since their last common eusocial ancestor.


Subject(s)
Bees , Behavior, Animal , Gene Expression Profiling , Animals , Bees/genetics , Female , Gene Expression , Larva/genetics
14.
Cereb Cortex ; 30(9): 5180-5189, 2020 07 30.
Article in English | MEDLINE | ID: mdl-32488246

ABSTRACT

Decreased GABAergic inhibition due to dysfunction of inhibitory interneurons plays an important role in post-traumatic epileptogenesis. Reduced N-current Ca2+ channel function in GABAergic terminals contributes to interneuronal abnormalities and neural circuit hyperexcitability in the partial neocortical isolation (undercut, UC) model of post-traumatic epileptogenesis. Because brain-derived neurotrophic factor (BDNF) supports the development and maintenance of interneurons, we hypothesized that the activation of BDNF tropomyosin kinase B (TrkB) receptors by a small molecule, TrkB partial agonist, PTX BD4-3 (BD), would correct N channel abnormalities and enhance inhibitory synaptic transmission in UC cortex. Immunocytochemistry (ICC) and western blots were used to quantify N- and P/Q-type channels. We recorded evoked (e)IPSCs and responses to N and P/Q channel blockers to determine the effects of BD on channel function. Field potential recordings were used to determine the effects of BD on circuit hyperexcitability. Chronic BD treatment 1) upregulated N and P/Q channel immunoreactivity in GABAergic terminals; 2) increased the effects of N or P/Q channel blockade on evoked inhibitory postsynaptic currents (eIPSCs); 3) increased GABA release probability and the frequency of sIPSCs; and 4) reduced the incidence of epileptiform discharges in UC cortex. The results suggest that chronic TrkB activation is a promising approach for rescuing injury-induced calcium channel abnormalities in inhibitory terminals, thereby improving interneuronal function and suppressing circuit hyperexcitability.


Subject(s)
Interneurons/metabolism , Neocortex/metabolism , Receptor, trkB/metabolism , Synaptic Transmission/physiology , Animals , Brain Injuries/complications , Brain Injuries/metabolism , Calcium Channels/metabolism , Epilepsy/etiology , Epilepsy/metabolism , Male , Neocortex/injuries , Rats , Rats, Sprague-Dawley
15.
Neurobiol Dis ; 142: 104949, 2020 08.
Article in English | MEDLINE | ID: mdl-32442680

ABSTRACT

Long-term consequences of status epilepticus (SE) occur in a significant proportion of those who survive the acute episode. We developed an in vivo model of acute focal neocortical SE (FSE) to study long-term effects on local cortical structure and function and potential strategies to mitigate adverse consequences of SE. An acute 2 h episode of FSE was induced in anesthetized mice by epidural application of gabazine +4-aminopyridine over sensorimotor neocortex. Ten and 30 days later, the morphological and functional consequences of this single episode of FSE were studied using immunocytochemical and electrophysiological techniques. Results, focused on cortical layer V, showed astrogliosis, microgliosis, decreased neuronal density, and increased excitatory synapses, along with increased immunoreactivity for thrombospondin 2 (TSP2) and α2δ-1 proteins. In addition, neocortical slices, obtained from the area of prior focal seizure activity, showed abnormal epileptiform burst discharges along with increases in the frequency of miniature and spontaneous excitatory postsynaptic currents in layer V pyramidal cells, together with decreases in both parvalbumin immunoreactivity (PV-IR) and the frequency of miniature inhibitory postsynaptic currents in layer V pyramidal cells. Treatment with an approved drug, gabapentin (GBP) (ip 100 mg/kg/day 3×/day for 7 days following the FSE episode), prevented the gliosis, the enhanced TSP2- and α2δ-1- IR and the increased excitatory synaptic density in the affected neocortex. This model provides an approach for assessing adverse effects of FSE on neocortical structure and function and potential prophylactic treatments.


Subject(s)
Anticonvulsants/therapeutic use , Gabapentin/therapeutic use , Pyramidal Cells/drug effects , Sensorimotor Cortex/drug effects , Status Epilepticus/drug therapy , Animals , Anticonvulsants/pharmacology , Excitatory Postsynaptic Potentials/drug effects , Gabapentin/pharmacology , Mice , Sensorimotor Cortex/physiopathology , Status Epilepticus/physiopathology
16.
Epilepsia ; 61(3): 359-386, 2020 03.
Article in English | MEDLINE | ID: mdl-32196665

ABSTRACT

Prevention of epilepsy is a great unmet need. Acute central nervous system (CNS) insults such as traumatic brain injury (TBI), cerebrovascular accidents (CVA), and CNS infections account for 15%-20% of all epilepsy. Following TBI and CVA, there is a latency of days to years before epilepsy develops. This allows treatment to prevent or modify postinjury epilepsy. No such treatment exists. In animal models of acquired epilepsy, a number of medications in clinical use for diverse indications have been shown to have antiepileptogenic or disease-modifying effects, including medications with excellent side effect profiles. These include atorvastatin, ceftriaxone, losartan, isoflurane, N-acetylcysteine, and the antiseizure medications levetiracetam, brivaracetam, topiramate, gabapentin, pregabalin, vigabatrin, and eslicarbazepine acetate. In addition, there are preclinical antiepileptogenic data for anakinra, rapamycin, fingolimod, and erythropoietin, although these medications have potential for more serious side effects. However, except for vigabatrin, there have been almost no translation studies to prevent or modify epilepsy using these potentially "repurposable" medications. We may be missing an opportunity to develop preventive treatment for epilepsy by not evaluating these medications clinically. One reason for the lack of translation studies is that the preclinical data for most of these medications are disparate in terms of types of injury, models within different injury type, dosing, injury-treatment initiation latencies, treatment duration, and epilepsy outcome evaluation mode and duration. This makes it difficult to compare the relative strength of antiepileptogenic evidence across the molecules, and difficult to determine which drug(s) would be the best to evaluate clinically. Furthermore, most preclinical antiepileptogenic studies lack information needed for translation, such as dose-blood level relationship, brain target engagement, and dose-response, and many use treatment parameters that cannot be applied clinically, for example, treatment initiation before or at the time of injury and dosing higher than tolerated human equivalent dosing. Here, we review animal and human antiepileptogenic evidence for these medications. We highlight the gaps in our knowledge for each molecule that need to be filled in order to consider clinical translation, and we suggest a platform of preclinical antiepileptogenesis evaluation of potentially repurposable molecules or their combinations going forward.


Subject(s)
Anticonvulsants/therapeutic use , Antioxidants/therapeutic use , Epilepsy, Post-Traumatic/prevention & control , Epilepsy/prevention & control , GABA Agents/therapeutic use , Immunologic Factors/therapeutic use , Neuroprotective Agents/therapeutic use , Acetylcysteine/therapeutic use , Animals , Atorvastatin/therapeutic use , Brain Injuries, Traumatic/complications , Ceftriaxone/therapeutic use , Dibenzazepines/therapeutic use , Drug Repositioning , Epilepsy/etiology , Erythropoietin/therapeutic use , Fingolimod Hydrochloride/therapeutic use , Gabapentin/therapeutic use , Humans , Inflammation , Interleukin 1 Receptor Antagonist Protein/therapeutic use , Isoflurane/therapeutic use , Levetiracetam/therapeutic use , Losartan/therapeutic use , Oxidative Stress , Pregabalin/therapeutic use , Pyrrolidinones/therapeutic use , Sirolimus/therapeutic use , Stroke/complications , Topiramate/therapeutic use , Translational Research, Biomedical , Vigabatrin/therapeutic use
17.
Crit Care Med ; 47(7): 885-893, 2019 07.
Article in English | MEDLINE | ID: mdl-30985390

ABSTRACT

OBJECTIVES: To measure the impact of staged implementation of full versus partial ABCDE bundle on mechanical ventilation duration, ICU and hospital lengths of stay, and cost. DESIGN: Prospective cohort study. SETTING: Two medical ICUs within Montefiore Healthcare Center (Bronx, NY). PATIENTS: One thousand eight hundred fifty-five mechanically ventilated patients admitted to ICUs between July 2011 and July 2014. INTERVENTIONS: At baseline, spontaneous (B)reathing trials (B) were ongoing in both ICUs; in period 1, (A)wakening and (D)elirium (AD) were implemented in both full and partial bundle ICUs; in period 2, (E)arly mobilization and structured bundle (C)oordination (EC) were implemented in the full bundle (B-AD-EC) but not the partial bundle ICU (B-AD). MEASUREMENTS AND MAIN RESULTS: In the full bundle ICU, 95% patient days were spent in bed before EC (period 1). After EC was implemented (period 2), 65% of patients stood, 54% walked at least once during their ICU stay, and ICU-acquired pressure ulcers and physical restraint use decreased (period 1 vs 2: 39% vs 23% of patients; 30% vs 26% patient days, respectively; p < 0.001 for both). After adjustment for patient-level covariates, implementation of the full (B-AD-EC) versus partial (B-AD) bundle was associated with reduced mechanical ventilation duration (-22.3%; 95% CI, -22.5% to -22.0%; p < 0.001), ICU length of stay (-10.3%; 95% CI, -15.6% to -4.7%; p = 0.028), and hospital length of stay (-7.8%; 95% CI, -8.7% to -6.9%; p = 0.006). Total ICU and hospital cost were also reduced by 24.2% (95% CI, -41.4% to -2.0%; p = 0.03) and 30.2% (95% CI, -46.1% to -9.5%; p = 0.007), respectively. CONCLUSIONS: In a clinical practice setting, the addition of (E)arly mobilization and structured (C)oordination of ABCDE bundle components to a spontaneous (B)reathing, (A)wakening, and (D) elirium management background led to substantial reductions in the duration of mechanical ventilation, length of stay, and cost.


Subject(s)
Critical Care/organization & administration , Intensive Care Units/organization & administration , Patient Care Bundles/methods , Practice Guidelines as Topic/standards , Respiration, Artificial , Aged , Critical Care/economics , Critical Care/standards , Delirium/epidemiology , Delirium/therapy , Early Ambulation/methods , Female , Hospital Costs , Humans , Intensive Care Units/economics , Intensive Care Units/standards , Male , Middle Aged , Patient Care Bundles/economics , Patient Care Team/organization & administration , Pressure Ulcer/prevention & control , Prospective Studies , Respiration , Restraint, Physical/standards
18.
Med J Aust ; 211(10): 461-467, 2019 11.
Article in English | MEDLINE | ID: mdl-31680263

ABSTRACT

OBJECTIVES: To assess the clinical effectiveness of faecal calprotectin (FC) testing for distinguishing between organic gastrointestinal diseases (organic GID), such as inflammatory bowel disease (IBD), and functional gastrointestinal disorders (functional GIDs). STUDY DESIGN: Studies that assessed the accuracy of FC testing for differentiating between IBD or organic GID and functional GIDs were reviewed. Articles published in English during January 1998 - June 2018 that compared diagnostic FC testing in primary care and outpatient hospital settings with a reference test and employed the standard enzyme-linked immunosorbent FC assay method with a cut-off of 50 or 100 µg/g faeces were included. Study quality was assessed with QUADAS-2, an evidence-based quality assessment tool for diagnostic accuracy studies. DATA SOURCES: MEDLINE and EMBASE; reference lists of screened articles. DATA SYNTHESIS: Eighteen relevant studies were identified. For distinguishing patients with organic GID (including IBD) from those with functional GIDs (16 studies), the estimated sensitivity of FC testing was 81% (95% CI, 74-86%), the specificity 81% (95% CI, 71-88%); area under the curve (AUC) was 0.87. For distinguishing IBD from functional GIDs (ten studies), sensitivity was 88% (95% CI, 80-93%), specificity 72% (95% CI, 59-82%), and AUC 0.89. Assuming a population prevalence of organic GID of 1%, the positive predictive value was 4.2%, the negative predictive value 100%. The difference in sensitivity and specificity between FC testing cut-offs of 50 µg/g and 100 µg/g faeces was not statistically significant (P = 0.77). CONCLUSIONS: FC testing is clinically useful for distinguishing organic GID (including IBD) from functional GIDs, and its incorporation into clinical practice for evaluating patients with lower gastrointestinal symptoms could lead to fewer patients with functional GIDs undergoing colonoscopy, reducing costs for both patients and the health system. PROSPERO REGISTRATION: CRD4201810507.


Subject(s)
Feces/chemistry , Inflammatory Bowel Diseases/diagnosis , Leukocyte L1 Antigen Complex/analysis , Adult , Child , Child, Preschool , Humans , Inflammatory Bowel Diseases/epidemiology , Inflammatory Bowel Diseases/metabolism , Middle Aged
19.
Neurobiol Dis ; 113: 45-58, 2018 05.
Article in English | MEDLINE | ID: mdl-29408225

ABSTRACT

Post-traumatic epilepsy is one of the most common and difficult to treat forms of acquired epilepsy worldwide. Currently, there is no effective way to prevent post-traumatic epileptogenesis. It is known that abnormalities of interneurons, particularly parvalbumin-containing interneurons, play a critical role in epileptogenesis following traumatic brain injury. Thus, enhancing the function of existing parvalbumin interneurons might provide a logical therapeutic approach to prevention of post-traumatic epilepsy. The known positive effects of brain-derived neurotrophic factor on interneuronal growth and function through activation of its receptor tropomyosin receptor kinase B, and its decrease after traumatic brain injury, led us to hypothesize that enhancing trophic support might improve parvalbumin interneuronal function and decrease epileptogenesis. To test this hypothesis, we used the partial neocortical isolation ('undercut', UC) model of posttraumatic epileptogenesis in mature rats that were treated for 2 weeks, beginning on the day of injury, with LM22A-4, a newly designed partial agonist at the tropomyosin receptor kinase B. Effects of treatment were assessed with Western blots to measure pAKT/AKT; immunocytochemistry and whole cell patch clamp recordings to examine functional and structural properties of GABAergic interneurons; field potential recordings of epileptiform discharges in vitro; and video-EEG recordings of PTZ-induced seizures in vivo. Results showed that LM22A-4 treatment 1) increased pyramidal cell perisomatic immunoreactivity for VGAT, GAD65 and parvalbumin; 2) increased the density of close appositions of VGAT/gephyrin immunoreactive puncta (putative inhibitory synapses) on pyramidal cell somata; 3) increased the frequency of mIPSCs in pyramidal cells; and 4) decreased the incidence of spontaneous and evoked epileptiform discharges in vitro. 5) Treatment of rats with PTX BD4-3, another partial TrkB receptor agonist, reduced the incidence of bicuculline-induced ictal episodes in vitro and PTZ induced electrographic and behavioral ictal episodes in vivo. 6) Inactivation of TrkB receptors in undercut TrkBF616A mice with 1NMPP1 abolished both LM22A-4-induced effects on mIPSCs and on increased perisomatic VGAT-IR. Results indicate that chronic activation of the tropomyosin receptor kinase B by a partial agonist after cortical injury can enhance structural and functional measures of GABAergic inhibition and suppress posttraumatic epileptogenesis. Although the full agonist effects of brain-derived neurotrophic factor and tropomyosin receptor kinase B activation in epilepsy models have been controversial, the present results indicate that such trophic activation by a partial agonist may potentially serve as an effective therapeutic option for prophylactic treatment of posttraumatic epileptogenesis, and treatment of other neurological and psychiatric disorders whose pathogenesis involves impaired parvalbumin interneuronal function.


Subject(s)
Epilepsy/metabolism , Interneurons/metabolism , Membrane Glycoproteins/metabolism , Parvalbumins/metabolism , Protein-Tyrosine Kinases/metabolism , Somatosensory Cortex/metabolism , Animals , Epilepsy/physiopathology , Excitatory Postsynaptic Potentials/drug effects , Excitatory Postsynaptic Potentials/physiology , Interneurons/drug effects , Male , Membrane Glycoproteins/agonists , Mice , Mice, Transgenic , Organ Culture Techniques , Random Allocation , Rats , Rats, Sprague-Dawley , Somatosensory Cortex/drug effects , Vesicular Inhibitory Amino Acid Transport Proteins/metabolism , Vesicular Inhibitory Amino Acid Transport Proteins/pharmacology
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