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1.
Liver Int ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38967425

ABSTRACT

BACKGROUND AND AIMS: Mother-to-child-transmission (MTCT) of hepatitis B virus (HBV) may still occur despite birth-dose HBV vaccinations when pregnant women are positive for hepatitis B surface antigen (HBsAg) with high viral loads (HBV DNA ≥ 200 000 IU/mL). A pilot integrated model nurse clinic (IMNC) was started in 2020 to implement the pre-emptive antiviral therapy with tenofovir disoproxil fumarate (TDF). We aimed to evaluate the performance of IMNC on uptake of TDF. METHODS: This was a territory-wide retrospective cohort of all consecutive HBsAg-positive women of child-bearing age with pregnancy records in public hospitals 2019-2022. Demographic characteristics, liver biochemistries and virologic parameters, and TDF use were collected. Concurrently, data from a prospective audit in Union Hospital, the private hospital with the highest number of deliveries in Hong Kong, from June 2022 to May 2023 were compared. RESULTS: The prevalence rate of HBV DNA ≥ 200 000 IU/mL in pregnant women with available HBV DNA records was 29.2% (66/226) in 2019, 27.3% (99/363) in 2020, 15.9% (125/784) in 2021 and 17.2% (117/679) in 2022 (p < .001), out of 2052 pregnant women who had their HBV DNA checked within 1 year prior to delivery. An increasing uptake rate of TDF by highly viraemic pregnant women (i.e. ≥ 200 000 IU/mL) was noted after the commencement of IMNC in public hospitals, with 67% (45/67) in 2019, 83% (88/106) in 2020, 91% (117/128) in 2021 and 89% (149/167) in 2022. Moreover, all highly viraemic pregnant women from Union Hospital received TDF. Continuous use of TDF was associated with a reduced risk of postpartum biochemical flare. CONCLUSIONS: IMNC increases the uptake of antiviral treatment in pregnant women at risk of MTCT of HBV. IMNC contributes to hepatitis elimination through a structured care plan to prevent MTCT of HBV.

2.
Liver Transpl ; 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38647419

ABSTRACT

Acute allograft rejection is a well-known complication of liver transplantation (LT). The incidence, epidemiology, and outcomes of acute rejection have not been well described in Australia. We retrospectively studied consecutive adults who underwent deceased donor LT at a single center between 2010 and 2020. Donor and recipient data at the time of LT and recipient outcomes were collected from a prospective LT database. Liver biopsy reports were reviewed, and only a graft's first instance of biopsy-proven acute rejection was analyzed. During the study period, 796 liver transplants were performed in 770 patients. Biopsy-proven rejection occurred in 34.9% of transplants. There were no significant changes in the incidence of rejection over time (linear trend p =0.11). The median time to the first episode of rejection was 71 days after LT: 2.2% hyperacute, 50.4% early (≤90 d), and 47.5% late rejection (>90 d). Independent risk factors for rejection were younger recipient age at transplant (aHR 0.98 per year increase, 95% CI: 0.97-1.00, p =0.01), and ABO-incompatible grafts (aHR 2.55 vs. ABO-compatible, 95% CI: 1.27-5.09, p <0.01) while simultaneous multiorgan transplants were protective (aHR 0.21 vs. LT only, 95% CI: 0.08-0.58, p <0.01). Development of acute rejection (both early and late) was independently associated with significantly reduced graft (aHR 3.13, 95% CI: 2.21-4.42, p <0.001) and patient survival (aHR 3.42, 95% CI: 2.35-4.98, p <0.001). In this 11-year Australian study, acute LT rejection occurred in 35%, with independent risk factors of younger recipient age and ABO-incompatible transplant, while having a simultaneous multiorgan transplant was protective. Acute rejection was independently associated with reduced graft and patient survival after adjustment for other factors.

3.
J Neurosci Res ; 102(3): e25295, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38515329

ABSTRACT

Alzheimer's disease (AD) is a progressive neurodegenerative disease and the most common cause of dementia, characterized by deposition of extracellular amyloid-beta (Aß) aggregates and intraneuronal hyperphosphorylated Tau. Many AD risk genes, identified in genome-wide association studies (GWAS), are expressed in microglia, the innate immune cells of the central nervous system. Specific subtypes of microglia emerged in relation to AD pathology, such as disease-associated microglia (DAMs), which increased in number with age in amyloid mouse models and in human AD cases. However, the initial transcriptional changes in these microglia in response to amyloid are still unknown. Here, to determine early changes in microglia gene expression, hippocampal microglia from male APPswe/PS1dE9 (APP/PS1) mice and wild-type littermates were isolated and analyzed by RNA sequencing (RNA-seq). By bulk RNA-seq, transcriptomic changes were detected in hippocampal microglia from 6-months-old APP/PS1 mice. By performing single-cell RNA-seq of CD11c-positive and negative microglia from 6-months-old APP/PS1 mice and analysis of the transcriptional trajectory from homeostatic to CD11c-positive microglia, we identified a set of genes that potentially reflect the initial response of microglia to Aß.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Animals , Humans , Infant , Male , Mice , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/genetics , Disease Models, Animal , Genome-Wide Association Study , Mice, Transgenic , Microglia/metabolism , Neurodegenerative Diseases/genetics , Neurodegenerative Diseases/metabolism , Plaque, Amyloid , Presenilin-1/genetics , Transcriptome
4.
Nat Commun ; 15(1): 1880, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38424098

ABSTRACT

Drugs that target pre-mRNA splicing hold great therapeutic potential, but the quantitative understanding of how these drugs work is limited. Here we introduce mechanistically interpretable quantitative models for the sequence-specific and concentration-dependent behavior of splice-modifying drugs. Using massively parallel splicing assays, RNA-seq experiments, and precision dose-response curves, we obtain quantitative models for two small-molecule drugs, risdiplam and branaplam, developed for treating spinal muscular atrophy. The results quantitatively characterize the specificities of risdiplam and branaplam for 5' splice site sequences, suggest that branaplam recognizes 5' splice sites via two distinct interaction modes, and contradict the prevailing two-site hypothesis for risdiplam activity at SMN2 exon 7. The results also show that anomalous single-drug cooperativity, as well as multi-drug synergy, are widespread among small-molecule drugs and antisense-oligonucleotide drugs that promote exon inclusion. Our quantitative models thus clarify the mechanisms of existing treatments and provide a basis for the rational development of new therapies.


Subject(s)
Muscular Atrophy, Spinal , Pyrimidines , RNA Splicing , Humans , RNA Splicing/genetics , Azo Compounds , Oligonucleotides/genetics , Oligonucleotides, Antisense/genetics , Oligonucleotides, Antisense/therapeutic use , RNA Splice Sites , Muscular Atrophy, Spinal/drug therapy , Muscular Atrophy, Spinal/genetics
5.
Alzheimers Dement ; 20(3): 1637-1655, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38055782

ABSTRACT

INTRODUCTION: Early-life stress (ES) increases the risk for Alzheimer's disease (AD). We and others have shown that ES aggravates amyloid-beta (Aß) pathology and promotes cognitive dysfunction in APP/PS1 mice, but underlying mechanisms remain unclear. METHODS: We studied how ES affects the hippocampal synaptic proteome in wild-type (WT) and APP/PS1 mice at early and late pathological stages, and validated hits using electron microscopy and immunofluorescence. RESULTS: The hippocampal synaptosomes of both ES-exposed WT and early-stage APP/PS1 mice showed a relative decrease in actin dynamics-related proteins and a relative increase in mitochondrial proteins. ES had minimal effects on older WT mice, while strongly affecting the synaptic proteome of advanced stage APP/PS1 mice, particularly the expression of astrocytic and mitochondrial proteins. DISCUSSION: Our data show that ES and amyloidosis share pathogenic pathways involving synaptic mitochondrial dysfunction and lipid metabolism, which may underlie the observed impact of ES on the trajectory of AD.


Subject(s)
Adverse Childhood Experiences , Alzheimer Disease , Amyloidosis , Mice , Animals , Lipid Metabolism , Mice, Transgenic , Proteome , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Amyloidosis/metabolism , Mitochondria , Mitochondrial Proteins , Disease Models, Animal , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Presenilin-1/metabolism
6.
Percept Mot Skills ; 131(1): 246-266, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37997820

ABSTRACT

An important role of a Physical Education (PE) teacher is to assist students to develop the fundamental motor skills (FMS) that will allow them to participate in physical activities with competence and confidence. Thus, PE teachers require the knowledge and skills to carry out this crucial task. In the crowded curricula of Physical Education Teacher Education (PETE) programs, there are limited opportunities for pre-service PE teachers to learn how to analyze and perform a large list of motor skills. Our purposes in this study were to determine whether a single session peer-teaching intervention could improve pre-service PE teachers' short-term non-dominant hand overarm throwing performances and to examine these students' perceptions of the interventions. We allocated 47 pre-service PE teaching students (24 males; 23 females) to one of three experimental groups: a Video Analysis Group (VAG; n = 17), a Verbal Group (VG; n = 19), and a Control Group (CG; n = 11), based on the class in which they were enrolled. VAG and VG participants worked with a partner of their choice in reciprocal peer-teaching to improve each other's non-dominant hand throwing technique. VAG and VG interventions were identical except that VAG participants accessed video analysis technology. CG participants completed unrelated course work that involved no overarm throwing activities. A single 20-minute session of peer teaching with video analysis feedback during practice led to rapid enhancements in non-dominant hand overarm throwing skills. While all three groups improved their performance by retention testing, participants in the VAG group improved most quickly. Participants in both the VAG and VG groups reported that their respective interventions improved their throwing and Qualitative Movement Diagnosis (QMD) skills. Based on these results, we suggest that PETE programs integrate peer-teaching and video analysis sessions into fundamental movement courses to accelerate students' motor skill acquisitions.


Subject(s)
Curriculum , Physical Education and Training , Male , Female , Humans , Students , Learning , Feedback
7.
Hum Reprod ; 38(9): 1835-1842, 2023 09 05.
Article in English | MEDLINE | ID: mdl-37487110

ABSTRACT

STUDY QUESTION: Is exposure to toxic metal cadmium associated with increased endometriosis prevalence among a nationally representative sample of the US population? SUMMARY ANSWER: Concentrations of urinary cadmium, a long-term biomarker (10-30 years) of cadmium exposure, were associated with an increased prevalence of endometriosis. WHAT IS KNOWN ALREADY: Cadmium exhibits estrogenic properties and may increase the risk of endometriosis, a gynecologic condition associated with substantial morbidity, for which estrogen has a central pathogenic role. Previous epidemiological studies of cadmium and endometriosis have yielded mixed results, with null, positive, and inverse associations being reported. STUDY DESIGN, SIZE, DURATION: We conducted a cross-sectional study using data from four cycles of the National Health and Nutrition Examination Survey (NHANES) 1999-2006. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study population comprised participants aged 20-54 years who had an endometriosis diagnosis, available data on urinary cadmium, and a glomerular filtration rate ≥60 ml/min/1.73 m2 (unweighted n = 1647). Urinary cadmium was measured by inductively coupled plasma-mass spectrometry, and we used urinary creatinine concentrations and covariate-adjusted standardization to account for urinary dilution. Self-reported diagnosis of endometriosis was ascertained by interview. We examined the association between quartiles of urinary cadmium and endometriosis using log-binomial regression to estimate adjusted prevalence ratios (aPRs) and 95% CIs. MAIN RESULTS AND THE ROLE OF CHANCE: We observed twice the prevalence of endometriosis for participants with cadmium concentrations in the second quartile (versus the first quartile) (aPR 2.0, 95% CI: 1.1, 3.9) and the third quartile (versus the first quartile) (aPR 2.0, 95% CI: 1.1, 3.7). Our data also suggested a 60% increased prevalence of endometriosis with urinary cadmium concentrations in the fourth quartile (versus the first quartile) (aPR 1.6, 95% CI: 0.8, 3.2). In a sensitivity analysis, restricting the study population to premenopausal participants with an intact uterus and at least one ovary (unweighted n = 1298), stronger associations accompanied by wider CIs were observed. LIMITATIONS, REASONS FOR CAUTION: We were limited by the ascertainment of urinary cadmium and endometriosis diagnosis at a single time point, given the cross-sectional study design, and we relied on self-report of endometriosis diagnosis. However, urinary cadmium characterizes long-term exposure and findings from validation studies suggest that misclassification of self-reported endometriosis diagnosis may be minimal. WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that cadmium is associated with an increased endometriosis prevalence. Given the substantial morbidity conferred by endometriosis and that the general population is ubiquitously exposed to cadmium, further research is warranted to confirm our findings. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Institute of Nursing Research (grant R00NR017191 to K.U.) of the National Institutes of Health. The authors report no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.


Subject(s)
Endometriosis , United States/epidemiology , Humans , Female , Prevalence , Endometriosis/epidemiology , Cadmium , Nutrition Surveys , Cross-Sectional Studies
8.
J Sci Med Sport ; 26(9): 448-453, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37524626

ABSTRACT

OBJECTIVES: To explore Australian cricket participants' knowledge of concussion assessment and management, and awareness of current concussion guidelines. DESIGN: Cross-sectional survey. METHODS: Novel and validated surveys were disseminated online, among over 16 year Australian cricket players and officials at the end of the 2018/19 cricket season. Data were collected on knowledge and awareness of concussion and analysed using descriptive statistics and crosstabulations. Further comparisons were made for the players between injured and non-injured, and helmet wearers and non-helmet wearers using Fisher's exact statistical test. RESULTS: Both players (n = 224, 93 %) and officials (n = 36, 100 %) demonstrated strong knowledge of the importance of immediately evaluating suspected concussions. In comparison with players without helmets (n = 11), those using helmets (n = 135) considered replacing their helmets after a concussion to be vital to concussion assessment (p = 0.02). Overall, 80-97 % of players and 81-97 % of officials understood the importance of many factors regarding concussion management. When concussion management knowledge was compared by injury status, injured players (n = 17, 94 %) believed someone with a concussion should be hospitalised immediately, in contrast to non-injured players (n = 154, 69 %) (p = 0.04). Players (63 %) were less aware of concussion guidelines than officials (81 %). CONCLUSIONS: Overall, the knowledge of concussion assessment and management was satisfactory. However, there were discrepancies among players on some aspects of awareness of concussion guidelines. Increasing players' familiarity and experience in using the concussion guidelines is warranted. Targeted campaigns are needed to further improve concussion recognition and treatment at community-level cricket, so all participants play a role in making cricket a safe sport.


Subject(s)
Athletic Injuries , Brain Concussion , Cricket Sport , Football , Humans , Cross-Sectional Studies , Australia , Brain Concussion/diagnosis , Brain Concussion/prevention & control , Athletic Injuries/diagnosis , Athletic Injuries/prevention & control , Football/injuries
9.
Nat Commun ; 14(1): 2556, 2023 05 03.
Article in English | MEDLINE | ID: mdl-37137925

ABSTRACT

Lysine acetylation in histone tails is a key post-translational modification that controls transcription activation. Histone deacetylase complexes remove histone acetylation, thereby repressing transcription and regulating the transcriptional output of each gene. Although these complexes are drug targets and crucial regulators of organismal physiology, their structure and mechanisms of action are largely unclear. Here, we present the structure of a complete human SIN3B histone deacetylase holo-complex with and without a substrate mimic. Remarkably, SIN3B encircles the deacetylase and contacts its allosteric basic patch thereby stimulating catalysis. A SIN3B loop inserts into the catalytic tunnel, rearranges to accommodate the acetyl-lysine moiety, and stabilises the substrate for specific deacetylation, which is guided by a substrate receptor subunit. Our findings provide a model of specificity for a main transcriptional regulator conserved from yeast to human and a resource of protein-protein interactions for future drug designs.


Subject(s)
Histones , Lysine , Humans , Histones/metabolism , Lysine/metabolism , Protein Processing, Post-Translational , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , Acetylation , Histone Deacetylase 1/metabolism , Repressor Proteins/metabolism
10.
Glia ; 71(7): 1770-1785, 2023 07.
Article in English | MEDLINE | ID: mdl-37002718

ABSTRACT

Loss of function of the astrocyte membrane protein MLC1 is the primary genetic cause of the rare white matter disease Megalencephalic Leukoencephalopathy with subcortical Cysts (MLC), which is characterized by disrupted brain ion and water homeostasis. MLC1 is prominently present around fluid barriers in the brain, such as in astrocyte endfeet contacting blood vessels and in processes contacting the meninges. Whether the protein plays a role in other astrocyte domains is unknown. Here, we show that MLC1 is present in distal astrocyte processes, also known as perisynaptic astrocyte processes (PAPs) or astrocyte leaflets, which closely interact with excitatory synapses in the CA1 region of the hippocampus. We find that the PAP tip extending toward excitatory synapses is shortened in Mlc1-null mice. This affects glutamatergic synaptic transmission, resulting in a reduced rate of spontaneous release events and slower glutamate re-uptake under challenging conditions. Moreover, while PAPs in wildtype mice retract from the synapse upon fear conditioning, we reveal that this structural plasticity is disturbed in Mlc1-null mice, where PAPs are already shorter. Finally, Mlc1-null mice show reduced contextual fear memory. In conclusion, our study uncovers an unexpected role for the astrocyte protein MLC1 in regulating the structure of PAPs. Loss of MLC1 alters excitatory synaptic transmission, prevents normal PAP remodeling induced by fear conditioning and disrupts contextual fear memory expression. Thus, MLC1 is a new player in the regulation of astrocyte-synapse interactions.


Subject(s)
Astrocytes , Membrane Proteins , Synapses , Animals , Mice , Astrocytes/metabolism , Hereditary Central Nervous System Demyelinating Diseases/genetics , Membrane Proteins/metabolism , Mice, Knockout , Synapses/metabolism
11.
Front Cell Neurosci ; 17: 1085690, 2023.
Article in English | MEDLINE | ID: mdl-36779013

ABSTRACT

Introduction: Astrocyte-synapse bi-directional communication is required for neuronal development and synaptic plasticity. Astrocytes structurally interact with synapses using their distal processes also known as leaflets or perisynaptic astrocytic processes (PAPs). We recently showed that these PAPs are retracted from hippocampal synapses, and involved in the consolidation of fear memory. However, whether astrocytic synaptic coverage is affected when memory is impaired is unknown. Methods: Here, we describe in detail an electron microscopy method that makes use of a large number of 2D images to investigate structural astrocyte-synapse interaction in paraformaldehyde fixed brain tissue of mice. Results and discussion: We show that fear memory-induced synaptic activation reduces the interaction between the PAPs and the presynapse, but not the postsynapse, accompanied by retraction of the PAP tip from the synaptic cleft. Interestingly, this retraction is absent in the APP/PS1 mouse model of Alzheimer's disease, supporting the concept that alterations in astrocyte-synapse coverage contribute to memory processing.

12.
Biol Psychiatry ; 94(3): 226-238, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-36702661

ABSTRACT

BACKGROUND: The formation and retrieval of fear memories depends on orchestrated synaptic activity of neuronal ensembles within the hippocampus, and it is becoming increasingly evident that astrocytes residing in the environment of these synapses play a central role in shaping cellular memory representations. Astrocyte distal processes, known as leaflets, fine-tune synaptic activity by clearing neurotransmitters and limiting glutamate diffusion. However, how astroglial synaptic coverage contributes to mnemonic processing of fearful experiences remains largely unknown. METHODS: We used electron microscopy to observe changes in astroglial coverage of hippocampal synapses during consolidation of fear memory in mice. To manipulate astroglial synaptic coverage, we depleted ezrin, an integral leaflet-structural protein, from hippocampal astrocytes using CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 gene editing. Next, a combination of Föster resonance energy transfer analysis, genetically encoded glutamate sensors, and whole-cell patch-clamp recordings was used to determine whether the proximity of astrocyte leaflets to the synapse is critical for synaptic integrity and function. RESULTS: We found that consolidation of a recent fear memory is accompanied by a transient retraction of astrocyte leaflets from hippocampal synapses and increased activation of NMDA receptors. Accordingly, astrocyte-specific depletion of ezrin resulted in shorter astrocyte leaflets and reduced astrocyte contact with the synaptic cleft, which consequently boosted extrasynaptic glutamate diffusion and NMDA receptor activation. Importantly, after fear conditioning, these cellular phenotypes translated to increased retrieval-evoked activation of CA1 pyramidal neurons and enhanced fear memory expression. CONCLUSIONS: Together, our data show that withdrawal of astrocyte leaflets from the synaptic cleft is an experience-induced, temporally regulated process that gates the strength of fear memories.

13.
Fertil Steril ; 119(4): 644-652, 2023 04.
Article in English | MEDLINE | ID: mdl-36563837

ABSTRACT

OBJECTIVE: To evaluate the association between breastfeeding history, including lifetime exclusive breastfeeding, and risk of adenomyosis. DESIGN: We used data from a case-control study designed with 2 control groups to address the challenge of selecting noncases for a valid epidemiologic study when cases are identified by hysterectomy. The case-control study was conducted among premenopausal and postmenopausal enrollees aged 18-59 years in a large, integrated health care system in western Washington state. PATIENT(S): Cases were enrollees with incident, pathology-confirmed adenomyosis diagnosed during 2001-2006 (n = 386). The 2 control groups were as follows: (1) randomly selected age-matched enrollees with intact uteri ("population controls," n = 323) and (2) hysterectomy controls (n = 233). INTERVENTION(S): Data on breastfeeding history were collected by in-person interviews. For each reported live birth, participants were asked whether they breastfed, along with infant age at supplemental feeding introduction and breastfeeding discontinuation. MAIN OUTCOME MEASURE(S): Among participants with at least 1 live birth (330 cases, 246 population controls, and 198 hysterectomy controls), we used unconditional logistic regression to estimate adjusted odds ratios and 95% confidence intervals (CIs) for the associations between the following: (1) ever breastfeeding, (2) ever breastfeeding for ≥8 weeks, (3) lifetime breastfeeding, and (4) lifetime exclusive breastfeeding and risk of adenomyosis. Analyses were adjusted for age, reference year, smoking, education, and parity. RESULT(S): In analyses comparing cases with population controls, we observed a 40% decreased odds of adenomyosis with a history of ever breastfeeding (adjusted odds ratio, 0.6; 95% CI, 0.3-1.0) and breastfeeding for ≥8 weeks (adjusted odds ratio, 0.6; 95% CI, 0.4-0.8). The strongest associations, 60%-70% decreased odds of adenomyosis, were observed with ≥12 months of lifetime breastfeeding (vs. <3 months) (adjusted odds ratio, 0.4; 95% CI, 0.2-0.6) and 9 to <12 months of lifetime exclusive breastfeeding (vs. <3 months) (adjusted odds ratio, 0.3; 95% CI, 0.2-0.6), comparing cases to population controls. In analyses using hysterectomy controls, we observed similar patterns of associations slightly attenuated in magnitude. CONCLUSION(S): Breastfeeding history was associated with a 40% decreased odds of adenomyosis, a condition that can confer substantial morbidity and requires hysterectomy for definitive treatment. The consistency of our findings with that of a previous study lends support that breastfeeding may modify risk of adenomyosis.


Subject(s)
Adenomyosis , Breast Feeding , Infant , Pregnancy , Female , Humans , Case-Control Studies , Adenomyosis/diagnosis , Adenomyosis/epidemiology , Uterus , Parity
14.
Brain Behav Immun ; 107: 225-241, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36270437

ABSTRACT

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive decline, the neuropathological formation of amyloid-beta (Aß) plaques and neurofibrillary tangles. The best cellular correlates of the early cognitive deficits in AD patients are synapse loss and gliosis. In particular, it is unclear whether the activation of microglia (microgliosis) has a neuroprotective or pathological role early in AD. Here we report that microgliosis is an early mediator of synaptic dysfunction and cognitive impairment in APP/PS1 mice, a mouse model of increased amyloidosis. We found that the appearance of microgliosis, synaptic dysfunction and behavioral impairment coincided with increased soluble Aß42 levels, and occurred well before the presence of Aß plaques. Inhibition of microglial activity by treatment with minocycline (MC) reduced gliosis, synaptic deficits and cognitive impairments at early pathological stages and was most effective when provided preventive, i.e., before the onset of microgliosis. Interestingly, soluble Aß levels or Aß plaques deposition were not affected by preventive MC treatment at an early pathological stage (4 months) whereas these were reduced upon treatment at a later stage (6 months). In conclusion, this study demonstrates the importance of early-stage prevention of microgliosis on the development of cognitive impairment in APP/PS1 mice, which might be clinically relevant in preventing memory loss and delaying AD pathogenesis.


Subject(s)
Alzheimer Disease , Mice , Animals , Memory Disorders/prevention & control
15.
Cell Rep ; 41(3): 111474, 2022 10 18.
Article in English | MEDLINE | ID: mdl-36261025

ABSTRACT

Within eukaryotic cells, translation is regulated independent of transcription, enabling nuanced, localized, and rapid responses to stimuli. Neurons respond transcriptionally and translationally to synaptic activity. Although transcriptional responses are documented in astrocytes, here we test whether astrocytes have programmed translational responses. We show that seizure activity rapidly changes the transcripts on astrocyte ribosomes, some predicted to be downstream of BDNF signaling. In acute slices, we quantify the extent to which cues of neuronal activity activate translation in astrocytes and show that this translational response requires the presence of neurons, indicating that the response is non-cell autonomous. We also show that this induction of new translation extends into the periphery of astrocytes. Finally, synaptic proteomics show that new translation is required for changes that occur in perisynaptic astrocyte protein composition after fear conditioning. Regulation of translation in astrocytes by neuronal activity suggests an additional mechanism by which astrocytes may dynamically modulate nervous system functioning.


Subject(s)
Astrocytes , Proteome , Brain-Derived Neurotrophic Factor , Cell Membrane Structures , Proteomics
16.
Am J Hematol ; 97(11): 1435-1442, 2022 11.
Article in English | MEDLINE | ID: mdl-36053825

ABSTRACT

Buprenorphine, a novel opioid with complex pharmacology, is effective for treating pain and is qualitatively safer than high-dose full agonist opioid therapy; but transitioning to buprenorphine can be technically complex and carries some risk of precipitated withdrawal. We report our clinic's experience converting 36 patients with sickle cell disease (SCD) from full agonist opioids to buprenorphine using a method developed in the past 10 years. Thirty of these patients were induced using a standard outpatient protocol and six were induced during medical admissions. Typically, patients were on high-dose chronic opioid therapy (COT) with inadequate response, and often with very high acute care utilization. Unlike prior case series, the method of induction, dosing, and management of withdrawal are detailed, as are post-induction adverse events. There were seven adverse events in the first 3 days following standard induction, and two of which were judged to be definitely related to the induction but none with any lasting sequelae. At 6 months follow-up, five participants had discontinued buprenorphine (16.67%), and overall acute care visits dropped from a mean of 10.50 (SD 11.35) in the 6 months pre-induction to 2.89 (SD 3.40) in the 6 months post-induction. In an appropriately interdisciplinary care setting, buprenorphine shows promise as a safe alternative to COT with early evidence of benefit for high-utilizing patients with SCD.


Subject(s)
Anemia, Sickle Cell , Buprenorphine , Adult , Analgesics, Opioid/adverse effects , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/drug therapy , Buprenorphine/adverse effects , Hospitalization , Humans , Pain/drug therapy
17.
Proc Natl Acad Sci U S A ; 119(39): e2204233119, 2022 09 27.
Article in English | MEDLINE | ID: mdl-36129941

ABSTRACT

Contemporary high-throughput mutagenesis experiments are providing an increasingly detailed view of the complex patterns of genetic interaction that occur between multiple mutations within a single protein or regulatory element. By simultaneously measuring the effects of thousands of combinations of mutations, these experiments have revealed that the genotype-phenotype relationship typically reflects not only genetic interactions between pairs of sites but also higher-order interactions among larger numbers of sites. However, modeling and understanding these higher-order interactions remains challenging. Here we present a method for reconstructing sequence-to-function mappings from partially observed data that can accommodate all orders of genetic interaction. The main idea is to make predictions for unobserved genotypes that match the type and extent of epistasis found in the observed data. This information on the type and extent of epistasis can be extracted by considering how phenotypic correlations change as a function of mutational distance, which is equivalent to estimating the fraction of phenotypic variance due to each order of genetic interaction (additive, pairwise, three-way, etc.). Using these estimated variance components, we then define an empirical Bayes prior that in expectation matches the observed pattern of epistasis and reconstruct the genotype-phenotype mapping by conducting Gaussian process regression under this prior. To demonstrate the power of this approach, we present an application to the antibody-binding domain GB1 and also provide a detailed exploration of a dataset consisting of high-throughput measurements for the splicing efficiency of human pre-mRNA [Formula: see text] splice sites, for which we also validate our model predictions via additional low-throughput experiments.


Subject(s)
Epistasis, Genetic , RNA Precursors , Bayes Theorem , Chromosome Mapping , Computational Biology , Genotype , Humans , Models, Genetic , Mutation , Phenotype , RNA Splicing
18.
Int J Sports Med ; 43(6): 496-504, 2022 06.
Article in English | MEDLINE | ID: mdl-34729732

ABSTRACT

This systematic review was conducted to identify the incidence, nature and mechanisms of head, neck and facial (HNF) injuries in cricket and the reported use of helmets. Five databases were searched up to 30th November 2020. From peer-reviewed cricket injury studies published in English, studies reporting on HNF cricket injuries as per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were selected. Twenty-nine studies were included. HNF injuries had a cumulative total of 794/5,886 injuries equating to 13% of all injuries. Non- specified HNF injuries (n=210, 26%) were the most prevalent type of injury followed by non-specified head injuries (n=130, 16%), other non-specified fractures (n=119, 15%) and concussions (n=60, 8%).The impact of the ball was reported as the most common mechanism for sustaining HNF injuries in cricket. The use of helmet was reported in only three studies (10%). From studies reporting on HNF cricket injuries, facial fractures, and concussions were the most common specified-types of injury. There is little evidence on reporting of HNF cricket injuries as per the international cricket consensus injury definitions, as well as the use of helmets at the time of injury.


Subject(s)
Athletic Injuries , Brain Concussion , Craniocerebral Trauma , Facial Injuries , Athletic Injuries/complications , Athletic Injuries/epidemiology , Brain Concussion/complications , Craniocerebral Trauma/epidemiology , Facial Injuries/complications , Facial Injuries/epidemiology , Head Protective Devices/adverse effects , Humans , Incidence
19.
Front Chem ; 9: 659583, 2021.
Article in English | MEDLINE | ID: mdl-34026725

ABSTRACT

Sweat is emerging as a prominent biosource for real-time human performance monitoring applications. Although promising, sources of variability must be identified to truly utilize sweat for biomarker applications. In this proof-of-concept study, a targeted metabolomics method was applied to sweat collected from the forearms of participants in a 12-week exercise program who ingested either low or high nutritional supplementation twice daily. The data establish the use of dried powder mass as a method for metabolomic data normalization from sweat samples. Additionally, the results support the hypothesis that ingestion of regular nutritional supplementation semi-quantitatively impact the sweat metabolome. For example, a receiver operating characteristic (ROC) curve of relative normalized metabolite quantities show an area under the curve of 0.82 suggesting the sweat metabolome can moderately predict if an individual is taking nutritional supplementation. Finally, a significant correlation between physical performance and the sweat metabolome are established. For instance, the data illustrate that by utilizing multiple linear regression modeling approaches, sweat metabolite quantities can predict VO2 max (p = 0.0346), peak lower body Windage (p = 0.0112), and abdominal circumference (p = 0.0425). The results illustrate the need to account for dietary nutrition in biomarker discovery applications involving sweat as a biosource.

20.
Stem Cell Reports ; 16(4): 985-996, 2021 04 13.
Article in English | MEDLINE | ID: mdl-33711268

ABSTRACT

Combined with CRISPR-Cas9 technology and single-stranded oligodeoxynucleotides (ssODNs), specific single-nucleotide alterations can be introduced into a targeted genomic locus in induced pluripotent stem cells (iPSCs); however, ssODN knockin frequency is low compared with deletion induction. Although several Cas9 transduction methods have been reported, the biochemical behavior of CRISPR-Cas9 nuclease in mammalian cells is yet to be explored. Here, we investigated intrinsic cellular factors that affect Cas9 cleavage activity in vitro. We found that intracellular RNA, but not DNA or protein fractions, inhibits Cas9 from binding to single guide RNA (sgRNA) and reduces the enzymatic activity. To prevent this, precomplexing Cas9 and sgRNA before delivery into cells can lead to higher genome editing activity compared with Cas9 overexpression approaches. By optimizing electroporation parameters of precomplexed ribonucleoprotein and ssODN, we achieved efficiencies of single-nucleotide correction as high as 70% and loxP insertion up to 40%. Finally, we could replace the HLA-C1 allele with the C2 allele to generate histocompatibility leukocyte antigen custom-edited iPSCs.


Subject(s)
CRISPR-Associated Protein 9/metabolism , CRISPR-Cas Systems/genetics , Oligodeoxyribonucleotides/metabolism , RNA/metabolism , Ribonucleoproteins/metabolism , Alleles , Anti-Bacterial Agents/pharmacology , Base Sequence , Distal Myopathies/genetics , Distal Myopathies/therapy , Dysferlin/genetics , Dysferlin/metabolism , Exons/genetics , Gene Editing , HEK293 Cells , Haplotypes/genetics , Homozygote , Humans , Induced Pluripotent Stem Cells/metabolism , Muscular Atrophy/genetics , Muscular Atrophy/therapy , Muscular Dystrophy, Duchenne/genetics , Mutagenesis, Insertional/genetics , Mutation/genetics , RNA Splicing/genetics , RNA, Guide, Kinetoplastida/metabolism , Ribonucleases/metabolism
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