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1.
J Comp Neurol ; 532(6): e25624, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38896499

RESUMO

The hypothalamic suprachiasmatic nucleus (SCN) is the central pacemaker for mammalian circadian rhythms. As such, this ensemble of cell-autonomous neuronal oscillators with divergent periods must maintain coordinated oscillations. To investigate ultrastructural features enabling such synchronization, 805 coronal ultrathin sections of mouse SCN tissue were imaged with electron microscopy and aligned into a volumetric stack, from which selected neurons within the SCN core were reconstructed in silico. We found that clustered SCN core neurons were physically connected to each other via multiple large soma-to-soma plate-like contacts. In some cases, a sliver of a glial process was interleaved. These contacts were large, covering on average ∼21% of apposing neuronal somata. It is possible that contacts may be the electrophysiological substrate for synchronization between SCN neurons. Such plate-like contacts may explain why the synchronization of SCN neurons is maintained even when chemical synaptic transmission or electrical synaptic transmission via gap junctions is blocked. Such ephaptic contact-mediated synchronization among nearby neurons may therefore contribute to the wave-like oscillations of circadian core clock genes and calcium signals observed in the SCN.


Three­dimensional reconstruction of SCN tissue via serial electron microscopy revealed a novel structural feature of SCN neurons that may account for interneuronal synchronization that persists even when the predominant mechanisms of neuronal communication are blocked. We found that SCN core neurons are connected by multiple soma­soma contact specializations, ultrastructural elements that could enable synchronization of tightly packed neurons organized in clustered networks. This extensive network of plate­like soma­soma contacts among clustered SCN neurons may provide insight into how ∼20,000 autonomous neuronal oscillators with a broad range of intrinsic periods remain synchronized in the absence of ordinary communication modalities, thereby conferring the resilience required for the SCN to function as the mammalian circadian pacemaker.


Assuntos
Camundongos Endogâmicos C57BL , Animais , Camundongos , Neurônios do Núcleo Supraquiasmático/fisiologia , Masculino , Núcleo Supraquiasmático/fisiologia , Núcleo Supraquiasmático/citologia , Neurônios/fisiologia
2.
Diagn Microbiol Infect Dis ; 109(3): 116323, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38703530

RESUMO

PURPOSE: To evaluate the performance of a newly developed 2019-nCoV nucleic acid detection kit based on Ion Proton sequencing platform and make comparation with MGI Tech (DNBSEQ-G99) platform. METHODS: References and clinical samples were used to evaluate the precision, agreement rate, limit of detection (LOD), anti-interference ability and analytical specificity. Twenty-seven clinical specimens were used to make comparison between two platforms. RESULTS: The kit showed good intra-assay, inter-assay, inter-day precision between different operators and laboratories, fine agreement rate with references, a relatively low LOD of 1 × 103 copies/ml, anti-interference capability of 5 % whole blood and 1mg/ml mucin and no cross reaction with twenty-nine common clinical pathogens. Consistency of variant classification was observed between two platforms. The WGS from Ion Proton tended to have higher coverage and less missing data. CONCLUSIONS: The newly developed kit has shown satisfactory performances and excellent consistency with DNBSEQ-G99, making it a good alternative choice clinically.


Assuntos
COVID-19 , SARS-CoV-2 , Sensibilidade e Especificidade , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , RNA Viral/genética , Limite de Detecção , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Teste de Ácido Nucleico para COVID-19/métodos , Teste de Ácido Nucleico para COVID-19/instrumentação , Kit de Reagentes para Diagnóstico/normas
3.
JMIR Res Protoc ; 13: e53222, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38393754

RESUMO

BACKGROUND: Although the detrimental effects of conventional combustible cigarettes on oral health and dental esthetics are well known, there is limited information about the long-term impact of combustion-free nicotine alternatives (C-F NA) such as e-cigarettes or heated tobacco products. OBJECTIVE: This multicenter, prospective, 3-parallel-arm randomized controlled trial will investigate whether switching from combustible cigarettes to C-F NA will lead to measurable improvements in oral health parameters and dental esthetics over 18 months in adult smokers with limited gum disease. METHODS: Regular smokers not intending to quit and without clinical signs of periodontitis will be randomly assigned (1:4 ratio) to either standard of care with brief cessation advice (control group; arm A) or C-F NA use (intervention group; arm B). The study will also include a reference group of never smokers (reference group; arm C). The primary end point is the change in the Modified Gingival Index (MGI) score from baseline between the control arm (arm A) and the intervention arm (arm B) at the 18-month follow-up. In addition, the study will analyze the within- and between-group (arms A, B, and C) changes in MGI assessment, plaque imaging, dental shade quantitation, tooth stain scores, and oral health-related quality of life questionnaires measured at each study time point. All participants will attend a total of 7 clinic visits: screening, enrollment, and randomization (visit 0); baseline visit-day 14 (visit 1); day 90 (visit 2); day 180 (visit 3); day 360 (visit 4); and day 540 (visit 5). This multicenter study will be conducted in 4 dental clinics in 4 countries. The statistical analysis will involve descriptive statistics for continuous and categorical data. Primary end points will undergo tests for normality and, based on distribution, either a 2-sided t test or Mann-Whitney U test. Linear mixed model with random factors center and study arms by center will also be applied. Secondary end points, including MGI assessment and quality of life, will be subjected to similar tests and comparisons. Only if one value of the parameter MGI is missing after day 1, the last available observation will be carried forward. The analysis will be performed on the substituted data. Secondary parameters will not have missing value replacement. RESULTS: Participant recruitment began in October 2021, and enrollment was completed in June 2023. Results will be reported in 2025. CONCLUSIONS: This will be the first study to provide key insights into oral health benefits or risks associated with using C-F NA in smokers who are seeking alternatives to cigarette smoking. TRIAL REGISTRATION: ClinicalTrials.gov NCT04649645; https://clinicaltrials.gov/ct2/show/NCT04649645. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53222.

4.
Microbiol Resour Announc ; 13(2): e0068123, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38236017

RESUMO

In this report, we present the whole-genome sequences of Beauveria bassiana KNU-101, a widely recognized entomopathogenic fungus used as a biopesticide. The genome was assembled using a hybrid assembly approach, resulting in 13 scaffolds with a total size of 35,638,224 bp.

5.
BMC Res Notes ; 16(1): 316, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932861

RESUMO

OBJECTIVES: Pythium insidiosum causes a difficult-to-treat infectious condition called pythiosis, with high morbidity and mortality. So far, genome data of at least 10 strains of P. insidiosum, primarily classified in the phylogenetic clades I and II, have been sequenced using various next-generation sequencing platforms. The MGI short-read platform was employed to obtain genome data of 2 clade-III strains of P. insidiosum (recently reclassified as Pythium periculosum) from patients in Thailand and the United States. This work is a part of our attempt to generate a comprehensive genome database from diverse pathogen strains. DATA DESCRIPTION: A 150-bp paired-end library was prepared from a gDNA sample of P. insidiosum (P. periculosum) strains Pi057C3 and Pi050C3 (also known as ATCC90586) to generate draft genome sequences using an MGISEQ-2000RS sequencer. As a result, for the strain Pi057C3, we obtained a 42.5-Mb assembled genome (164x coverage) comprising 14,134 contigs, L50 of 241, N50 of 45,748, 57.6% CG content, and 12,147 ORFs. For the strain Pi050C3, we received a 43.3-Mb draft genome (230x coverage) containing 14,511 contigs, L50 of 245, N50 of 45,208, 57.7% CG content, and 12,249 ORFs. The genome sequences have been deposited in the NCBI/DDBJ databases under the accession numbers JAKCXM000000000.1 (strain Pi057C3) and JAKCXL000000000.1 (strain Pi050C3).


Assuntos
Pitiose , Pythium , Animais , Humanos , Filogenia , Pythium/genética , Genoma , Biblioteca Gênica
6.
J Dent ; 131: 104472, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36849066

RESUMO

OBJECTIVES: Does a complex intervention of oral hygiene advice (OHA) delivered with intra-oral scanner images, anti-gingivitis toothpaste and motivational reminders, improve oral health more than a standard of care control arm of fluoride toothpaste, with OHA without scanner images? METHODS: Adult participants with pre-existing gingivitis were randomised to intervention or control. Following enrolment, baseline and each subsequent visit (V) (3-weeks, V2; 3-months, V3; 6-months, V4) followed the same schedule. Bleeding on Probing (BOP) was assessed and Intra Oral Scan IOS(1) recorded. Plaque was disclosed, scored and re-scanned (IOS(2)). The intervention group received OHA with IOS images, control group receiving OHA without IOS images. Participants brushed with their allocated toothpaste (fluoride, control; anti-gingivitis, intervention), IOS(3) was recorded. Between visits participants brushed with their allocated toothpaste, intervention group received motivational reminders. RESULTS: BOP scores from baseline were significantly improved in the intervention group compared to control at all visits for all surfaces (p<0.001); differences at V4 were 0.292 (all), 0.211 (buccal/labial) and 0.375 (lingual/palatal). Plaque scores from baseline pre-brushing to each visit pre- and post-brushing also favoured the intervention group, the difference always significant on lingual/palatal surfaces (p<0.05), significant for all but pre-brushing-V4 (p<0.05) on all surfaces, but only significant for pre-brushing-V3 (p<0.05) buccally/labially. Differences from baseline to post-brushing at V4 were: 0.200 (all), 0.098 (buccal/labial) and 0.291 (lingual/palatal). CONCLUSION: A complex intervention comprising OHA delivered with IOS-images, anti-gingivitis toothpaste and motivational reminders improved gingival health more than existing standard of care-OHA together with a standard fluoride toothpaste over a 6-month period. CLINICAL SIGNIFICANCE STATEMENT: Intra-oral scans (IOS) are now frequently used in general dental practice for a variety of purposes. IOS use, in combination with motivational texts and an anti-gingivitis toothpaste, could be further deployed to promote oral hygiene behaviour change in patients and improve gingival health, in a cost-effective manner.


Assuntos
Gengivite , Cremes Dentais , Adulto , Humanos , Cremes Dentais/uso terapêutico , Saúde Bucal , Fluoretos/uso terapêutico , Gengivite/prevenção & controle , Higiene Bucal/métodos , Índice de Placa Dentária
7.
J Anat ; 242(3): 402-416, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36317926

RESUMO

Ear pinna is a particular feature of mammals that shows several repair responses depending on age. Two millimeter hole made in the pinna of middle-aged female mice heals due to partial reconstitution of new tissues (limited regeneration), whereas a hole punched in the ear of young mice forms a scar tissue. In these studies, the injury is made in the center of the ear pinna, but little is known about the type of reparative response along the proximodistal polarity of the ear. This study evaluated the effect of pinna polarity, age, and sex in the ear hole-repairing response in Balb/c mice. Proximal injuries were repaired more efficiently by limited regeneration than wounds made in the middle region. Non-injured ear histological analysis revealed a higher presence of muscle, adipose tissue, cartilage, and larger blood vessels in the proximal ear area, which could influence ear hole closure by limited regeneration. To evaluate the healing response during ear growth, we punched a standard hole in the proximal area of the ear on postnatal day 21 and 8-month-old mice (adults). Thirty-five days after the wound, both groups reached the same wound closure, despite the greater proportional size of holes made in the younger mice. Ear growth also improved ear hole closure in male mice. These results suggest that ear growth accelerates hole closure, providing an example of enhanced regenerative abilities in growing structures. Finally, hole closure kinetics in the growing ear indicated an early re-differentiation phase exhibited at 14 days post-wound. In conclusion, ear topography and growth positively influenced the healing response to ear holes, making it a tractable model to study in mammals.


Assuntos
Pavilhão Auricular , Regeneração , Camundongos , Animais , Masculino , Feminino , Regeneração/fisiologia , Mamíferos , Camundongos Endogâmicos BALB C , Cartilagem , Camundongos Endogâmicos C57BL
8.
J Neurosci Res ; 100(10): 1908-1920, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35796387

RESUMO

The glymphatic system is a recently discovered glial-dependent macroscopic interstitial waste clearance system that promotes the efficient elimination of soluble proteins and metabolites from the central nervous system. Its anatomic foundation is the astrocytes and aquaporin-4 (AQP4) water channels on the endfeet of astrocytes. The aim of this study is to evaluate the plasticity of the spinal glymphatic system in male SD rats with painful diabetic neuropathy (PDN) induced by type 2 diabetes mellitus. PDN rats were modeled under a high-fat and high-glucose diet with a low dose of streptozotocin. MRI was applied to observe the infiltration and clearance of contrast to indicate the functional variability of the glymphatic system at the spinal cord level. The paw withdrawal threshold was used to represent mechanical allodynia. The numerical change of glial fibrillary acidic protein (GFAP) positive astrocytes was assessed and the polarity reversal of AQP4 protein was measured by immunofluorescence. As a result, deceased contrast infiltration and clearance, enhanced mechanical allodynia, increased number of GFAP positive astrocytes, and reversed polarity of AQP4 protein were found in the PDN rats. The above molecular level changes may contribute to the impairment of the spinal glymphatic system in PDN rats. This study revealed the molecular and functional variations of the spinal glymphatic system in PDN rats and for the first time indicated that there might be a correlation between the impaired spinal glymphatic system and PDN rats.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Sistema Glinfático , Animais , Aquaporina 4/metabolismo , Diabetes Mellitus Tipo 2/complicações , Neuropatias Diabéticas/metabolismo , Sistema Glinfático/metabolismo , Hiperalgesia/etiologia , Hiperalgesia/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
9.
JHEP Rep ; 4(6): 100483, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35571533

RESUMO

Background & Aims: Alpha-1 antitrypsin deficiency is caused by mutations in SERPINA1, most commonly homozygosity for the Pi∗Z variant, and can present as liver disease. While heterozygosity for Pi∗Z (Pi∗MZ) is linked to increased risk of cirrhosis, whether the Pi∗MZ genotype is associated with an increased rate of decompensation among patients who already have compensated cirrhosis is not known. Methods: This was a retrospective study of Michigan Genomics Initiative participants with baseline compensated cirrhosis. The primary predictors were Pi∗MZ or Pi∗MS genotype (vs. Pi∗MM). The primary outcomes were hepatic decompensation with ascites, hepatic encephalopathy, or variceal bleeding, or the combined endpoint of liver-related death or liver transplant, both modeled with Fine-Gray competing risk models. Results: We included 576 patients with baseline compensated cirrhosis who had undergone genotyping, of whom 474 had Pi∗MM, 49 had Pi∗MZ, and 52 had Pi∗MS genotypes. Compared to Pi∗MM genotype, Pi∗MZ was associated with increased rates of hepatic decompensation (hazard ratio 1.81; 95% CI 1.22-2.69; p = 0.003) and liver transplant or liver-related death (hazard ratio 2.07; 95% CI 1.21-3.52; p = 0.078). These associations remained significant after adjustment for severity of underlying liver disease, and were robust across subgroup analyses based on etiology, sex, obesity, and diabetes status. Pi∗MS was not associated with decompensation or death/transplantation. Conclusions: The SERPINA1 Pi∗MZ genotype is associated with an increased rate of hepatic decompensation and decreased transplant-free survival among patients with baseline compensated cirrhosis. Lay summary: There is a mutation in the gene SERPINA1 called Pi∗MZ which increases risk of liver scarring (cirrhosis); however, it is not known what effect Pi∗MZ has if someone already has cirrhosis. In this study, we found that people who had cirrhosis and Pi∗MZ developed complications from cirrhosis faster than those who did not have the mutation.

10.
BMC Neurol ; 22(1): 103, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303826

RESUMO

OBJECTIVE: To establish content validity of a single-item, migraine-specific symptom severity questionnaire for completion by migraine patients, key family members (KFMs) of migraine patients, and Healthcare Professionals (HCPs) who treat migraine patients. BACKGROUND: Migraine is a common disabling primary headache disorder with high prevalence and significant socioeconomic burden and personal impacts. There is a need for a global assessment of migraine symptom severity to evaluate potential new therapies from multiple perspectives. METHODS: The migraine Global Impression Item (mGI-I) was drafted and tested in a non-interventional, qualitative study comprising telephone interviews with 15 migraine patients, 15 KFMs of migraine patients, and 15 migraine treating HCPs. The mGI-I was drafted with two different item stem options and two different response scale options to ask about the patient's migraine from the perspective of each respondent. Cognitive interviews were conducted to test comprehensiveness, clarity and ease of completion of the different versions of the mGI-I iteratively in three sequential waves of respondents. RESULTS: Revisions were made to the draft mGI-I after Wave 1 and Wave 2 of the interviews. Changes were made to simplify the item stem (removing unnecessary text), make language more patient-friendly (e.g. use of "migraine attack"), and add clarity to the item stem for consistent interpretation (include descriptive language of migraine attacks). Across both waves there was a preference for a 5-point response scale compared to a 7-point scale. In Wave 3, all respondents found the revised instructions, item stem, and 5-point response scale comprehensive, easy to understand and to answer. No further changes to the mGI-I were made after Wave 3. CONCLUSIONS: This qualitative study of 45 total respondents across 3 subpopulations, established the content validity and appropriateness of the mGI-I in migraine patients, KFMs, and migraine-treating HCPs. The study specifically confirmed that the mGI-I is comprehensive, easily understood and answered for each respondent population.


Assuntos
Transtornos de Enxaqueca , Humanos , Transtornos de Enxaqueca/epidemiologia , Pesquisa Qualitativa , Inquéritos e Questionários
11.
Small ; 18(22): e2200418, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35315220

RESUMO

Rechargeable magnesium batteries (RMBs) are promising candidates to replace currently commercialized lithium-ion batteries (LIBs) in large-scale energy storage applications owing to their merits of abundant resources, low cost, high theoretical volumetric capacity, etc. However, the development of RMBs is still facing great challenges including the incompatibility of the electrolyte and the lack of suitable cathode materials with high reversible capacity and fast kinetics of Mg2+ . While tremendous efforts have been made to explore compatible electrolytes and appropriate electrode materials, the rational design of unconventional Mg-based battery systems is another effective strategy for achieving high electrochemical performance. This review specifically discusses the recent research progress of various Mg-based battery systems. First, the optimization of electrolyte and electrode materials for conventional RMBs is briefly discussed. Furthermore, various Mg-based battery systems, including Mg-chalcogen (S, Se, Te) batteries, Mg-halogen (Br2 , I2 ) batteries, hybrid-ion batteries, and Mg-based dual-ion batteries are systematically summarized. This review aims to provide a comprehensive understanding of different Mg-based battery systems, which can inspire latecomers to explore new strategies for the development of high-performance and practically available RMBs.

12.
J Neurosci Res ; 100(6): 1359-1369, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35316547

RESUMO

Interleukin-18 (IL-18), a pro-inflammatory cytokine, is thought to be associated with inflammation in many neurological diseases such as ischemic stroke and poststroke depression, but the role of IL-18 in inflammatory injury after intracerebral hemorrhage (ICH) remains unclear. In this study, we established the ICH model in male mice and found that IL-18 expression including protein and mRNA levels was significantly increased in brain tissues after ICH. Meanwhile, exogenous IL-18 exacerbated cerebral hematoma and neurological deficits following ICH. In the IL-18 knockout group, the size of hematoma and neurological functions after ICH was decreased compared with the wild-type group, suggesting the critical role of IL-18 on the modulation of brain injury after ICH. Importantly, exogenous IL-18 increased microglial activation in brain tissues after ICH. Furthermore, IL-18 knockout resulted in the reduction of activated microglia after ICH. These results indicated that IL-18 may regulate the inflammatory response after ICH through the activation of microglia. Thus, IL-18 is expected to be a promising therapeutic target for secondary brain injury after ICH.


Assuntos
Lesões Encefálicas , Interleucina-18 , Animais , Lesões Encefálicas/complicações , Lesões Encefálicas/metabolismo , Hemorragia Cerebral/tratamento farmacológico , Hematoma/complicações , Hematoma/metabolismo , Masculino , Camundongos , Microglia/metabolismo
13.
J Neurosci Res ; 100(4): 1105-1122, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35213755

RESUMO

Microglia are the innate immune cells of the central nervous system (CNS). In the adult uncompromised CNS, they have a highly ramified morphology and continuously extend and retract their processes. A subpopulation of microglial cells forms close soma-to-soma contacts with neurons and have been termed satellite microglia, yet the role of such interaction is largely unknown. Here, we analyzed the distribution of satellite microglia in different areas of the CNS of adult male mice applying transgenic- and immunolabeling of neuronal subtypes and microglia followed by three-dimensional imaging analysis. We quantified satellite microglia associated with GABAergic and glutamatergic neurons in the somatosensory cortex, striatum, and thalamus; with dopaminergic and serotonergic neurons in the basal forebrain and raphe nucleus, respectively; and with cerebellar Purkinje cell neurons. Satellite microglia in the retina were assessed qualitatively. Microglia form satellites with all neuronal subtypes studied, whereas a preference for a specific neuron subtype was not found. The occurrence and frequency of satellite microglia is determined by the histo-architectural organization of the brain area and the densities of neuronal somata therein.


Assuntos
Microglia , Neurônios , Animais , Encéfalo , Masculino , Camundongos , Microglia/fisiologia , Neurônios/fisiologia
14.
PeerJ ; 9: e12254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34703674

RESUMO

With the developments in DNA nanoball sequencing technologies and the emergence of new platforms, there is an increasing interest in their performance in comparison with the widely used sequencing-by-synthesis methods. Here, we test the consistency of metabarcoding results from DNBSEQ-G400RS (DNA nanoball sequencing platform by MGI-Tech) and NovaSeq 6000 (sequencing-by-synthesis platform by Illumina) platforms using technical replicates of DNA libraries that consist of COI gene amplicons from 120 soil DNA samples. By subjecting raw sequencing data from both platforms to a uniform bioinformatics processing, we found that the proportion of high-quality reads passing through the filtering steps was similar in both datasets. Per-sample operational taxonomic unit (OTU) and amplicon sequence variant (ASV) richness patterns were highly correlated, but sequencing data from DNBSEQ-G400RS harbored a higher number of OTUs. This may be related to the lower dominance of most common OTUs in DNBSEQ data set (thus revealing higher richness by detecting rare taxa) and/or to a lower effective read quality leading to generation of spurious OTUs. However, there was no statistical difference in the ASV and post-clustered ASV richness between platforms, suggesting that additional denoising step in the ASV workflow had effectively removed the 'noisy' reads. Both OTU-based and ASV-based composition were strongly correlated between the sequencing platforms, with essentially interchangeable results. Therefore, we conclude that DNBSEQ-G400RS and NovaSeq 6000 are both equally efficient high-throughput sequencing platforms to be utilized in studies aiming to apply the metabarcoding approach, but the main benefit of the former is related to lower sequencing cost.

15.
J Neurosci Res ; 99(10): 2743-2758, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34133797

RESUMO

Different mutations in the cadherin 23 (CDH23) gene in different genetic backgrounds have been linked to either syndromic or nonsyndromic forms of deafness in humans. We previously reported a progressive hearing loss (HL) mouse model, the Cdh23erl/erl mouse, which carries a 208T > C mutation causing an amino acid substitution at S70P in C57BL/6J mice. To investigate the differences in Cdh23 mutation-related HL in different genetic backgrounds, we used the CRISPR/Cas9 system to generate homozygous mice in the CBA/CaJ background that have the same base pair missense mutation (208T > C) (Cdh23erl2/erl2 ) as Cdh23erl/erl mice in the C57BL/6J background or a single base pair deletion (235G) (Cdh23V2J2/V2J2 ) in the Cdh23 gene at exon 5. The two mutant mice exhibit hearing impairment across a broad range of frequencies. The progression of HL in Cdh23erl2/erl2 mice is slower than that in Cdh23erl/erl mice. We also found structural abnormalities in the stereocilia of cochlear hair cells in Cdh23erl2/erl2 and Cdh23V2J2/V2J2 mice. Cdh23V2J2/V2J2 mice show signs of vestibular dysfunction in open field behavior and swimming tests. In addition, we observed hair bundle defects in vestibular hair cells in Cdh23V2J2/V2J2 mice. Our results suggest an interaction between the erl locus and the C57BL/6J background that exacerbates HL in Cdh23erl/erl mice. Moreover, our study confirms that the Cdh23 gene is essential for normal hearing and balance. These two novel mutant mouse strains provide excellent models for studying CDH23 mutation-related deafness in humans.


Assuntos
Pareamento de Bases/genética , Caderinas/genética , Perda Auditiva/genética , Mutação de Sentido Incorreto/genética , Fenótipo , Deleção de Sequência/genética , Sequência de Aminoácidos , Animais , Caderinas/deficiência , Feminino , Células Ciliadas Auditivas Internas , Perda Auditiva/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Knockout , Camundongos Transgênicos
16.
J Neurosci Res ; 99(9): 2046-2058, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34048600

RESUMO

Digging behavior is often used to test motor function and repetitive behaviors in mice. Different digging paradigms have been developed for behaviors related to anxiety and compulsion in mouse lines generated to recapitulate genetic mutations leading to psychiatric and neurological disorders. However, the interpretation of these tests has been confounded by the difficulty of determining the motivation behind digging in mice. Digging is a naturalistic mouse behavior that can be focused toward different goals, that is foraging for food, burrowing for shelter, burying objects, or even for recreation as has been shown for dogs, ferrets, and human children. However, the interpretation of results from current testing protocols assumes the motivation behind the behavior often concluding that increased digging is a repetitive or compulsive behavior. We asked whether providing a choice between different types of digging activities would increase sensitivity to assess digging motivation. Here, we present a test to distinguish between burrowing and exploratory digging in mice. We found that mice prefer burrowing when the option is available. When food restriction was used to promote a switch from burrowing to exploration, males readily switched from burrowing to digging outside, while females did not. In addition, when we tested a model of intellectual disability and autism spectrum disorder that had shown inconsistent results in the marble burying test, the Cc2d1a conditional knockout mouse, we found greatly reduced burrowing only in males. Our findings indicate that digging is a nuanced motivated behavior and suggest that male and female rodents may perform it differently.


Assuntos
Aprendizagem por Discriminação/fisiologia , Comportamento Exploratório/fisiologia , Privação de Alimentos/fisiologia , Caracteres Sexuais , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
17.
J Neurosci Res ; 99(8): 1957-1972, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33844860

RESUMO

Binge drinking is a common occurrence in the United States, but a high concentration of alcohol in the blood has been shown to have reinforcing and reciprocal effects on the neuroimmune system in both dependent and non-dependent scenarios. The first part of this study examined alcohol's effects on the astrocytic response in the central amygdala and basolateral amygdala (BLA) in a non-dependent model. C57BL/6J mice were given access to either ethanol, water, or sucrose during a "drinking in the dark" paradigm, and astrocyte number and astrogliosis were measured using immunohistochemistry. Results indicate that non-dependent consumption increased glial fibrillary acidic protein (GFAP) density but not the number of GFAP+ cells, suggesting that non-dependent ethanol is sufficient to elicit astrocyte activation. The second part of this study examined how astrocytes impacted behaviors and the neurochemistry related to alcohol using the chemogenetic tool, DREADDs (designer receptors exclusively activated by designer drugs). Transgenic GFAP-hM3Dq mice were administered clozapine N-oxide both peripherally, affecting the entire central nervous system (CNS), or directly into the BLA. In both instances, GFAP-Gq-signaling activation significantly reduced ethanol consumption and correlating blood ethanol concentrations. However, GFAP-Gq-DREADD activation throughout the CNS had more broad effects resulting in decreased locomotor activity and sucrose consumption. More targeted GFAP-Gq-signaling activation in the BLA only impacted ethanol consumption. Finally, a glutamate assay revealed that after GFAP-Gq-signaling activation glutamate concentrations in the amygdala were partially normalized to control levels. Altogether, these studies support the theory that astrocytes represent a viable target for alcohol use disorder therapies.


Assuntos
Astrócitos/metabolismo , Complexo Nuclear Basolateral da Amígdala/metabolismo , Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Etanol/farmacologia , Proteína Glial Fibrilar Ácida/metabolismo , Animais , Consumo Excessivo de Bebidas Alcoólicas/imunologia , Ácido Glutâmico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos
18.
J Neurosci Res ; 99(5): 1474-1495, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33583101

RESUMO

BNN20, a C17-spiroepoxy derivative of the neurosteroid dehydroepiandrosterone, has been shown to exhibit strong neuroprotective properties but its role in glial populations has not been assessed. Our aim was to investigate the effect of BNN20 on glial populations by using in vitro and in vivo approaches, taking advantage of the well-established lysophosphatidylcholine (LPC)-induced focal demyelination mouse model. Our in vivo studies, performed in male mice, showed that BNN20 treatment leads to an increased number of mature oligodendrocytes (OLs) in this model. It diminishes astrocytic accumulation during the demyelination phase leading to a faster remyelination process, while it does not affect oligodendrocyte precursor cell recruitment or microglia/macrophage accumulation. Additionally, our in vitro studies showed that BNN20 acts directly to OLs and enhances their maturation even after they were treated with LPC. This beneficial effect of BNN20 is mediated, primarily, through the neurotrophin receptor TrkA. In addition, BNN20 reduces microglial activation and their transition to their pro-inflammatory state upon lipopolysaccharides stimulation in vitro. Taken together our results suggest that BNN20 could serve as an important molecule to develop blood-brain barrier-permeable synthetic agonists of neurotrophin receptors that could reduce inflammation, protect and increase the number of functional OLs by promoting their differentiation/maturation.


Assuntos
Desidroepiandrosterona/análogos & derivados , Doenças Desmielinizantes/tratamento farmacológico , Doenças Desmielinizantes/metabolismo , Animais , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fatores de Crescimento Neural/administração & dosagem , Fatores de Crescimento Neural/metabolismo , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo
19.
J Dent ; 105: 103579, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33417977

RESUMO

OBJECTIVES: To compare gingival inflammation scores obtained chairside using the non-invasive modified gingival index (MGI) with MGI scores from an intraoral scan (IOS) captured at the clinical visit but viewed 10 days later. METHODS: Single visit, anterior teeth, observational, proof of concept study in healthy adult participants with a spectrum of gingival inflammation. One investigator performed both clinical and intraoral scan MGI assessments, a second repeated the MGI evaluation from the IOS. RESULTS: 23 participants aged 18-72 yielded data for 552 gingival sites. There was agreement at 90 % of sites comparing clinical with IOS MGI scores. The commonest disagreements were MGI grade 0 read as 1 and 2 read as 3, the highest single probability of error occurring where a clinical score of 0 was scored 1 from the IOS: 0.118 and 0.129 for examiners 1 and 2 respectively. The second most common probability of error occurred where an IOS score of 3 was scored clinically as 2: 0.089 and 0.097 for examiners 1 and 2 respectively. MGI scores from the scans were similar for both examiners (91 % agreement), with no discrepancies of greater than 1 scale point. There was very close agreement between clinical MGI and IOS colour/texture scores. CONCLUSION: This study conclusively demonstrated that the MGI score from the scanned image was very similar to the MGI scored clinically. This study confirms that a digital IOS accurately captures gingival contour images allowing a clinician to determine health or degree of gingival inflammation from it using MGI scores. CLINICAL SIGNIFICANCE STATEMENT: This study confirms that IOS images of teeth and soft tissues are sufficiently accurate to allow the clinical evaluation of health or inflammatory gingival status using non-invasive indices. IOS has great potential for efficient and accurate data capture, for general practice and research facilitating remote evaluation and data verification.


Assuntos
Placa Dentária , Gengivite , Adolescente , Adulto , Idoso , Índice de Placa Dentária , Gengivite/diagnóstico por imagem , Humanos , Inflamação/diagnóstico por imagem , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Adulto Jovem
20.
J Comp Neurol ; 529(5): 957-968, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32681585

RESUMO

Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a neurodegenerative disease due to mutations in TUBB4A. Patients suffer from extrapyramidal movements, spasticity, ataxia, and cognitive deficits. Magnetic resonance imaging features are hypomyelination and atrophy of the striatum and cerebellum. A correlation between the mutations and their cellular, tissue and organic effects is largely missing. The effects of these mutations on sensory functions have not been described so far. We have previously reported a rat carrying a TUBB4A (A302T) mutation and sharing most of the clinical and radiological signs with H-ABC patients. Here, for the first time, we did a comparative study of the hearing function in an H-ABC patient and in this mutant model. By analyzing hearing function, we found that there are no significant differences in the auditory brainstem response (ABR) thresholds between mutant rats and WT controls. Nevertheless, ABRs show longer latencies in central waves (II-IV) that in some cases disappear when compared to WT. The patient also shows abnormal AEPs presenting only Waves I and II. Distortion product of otoacoustic emissions and immunohistochemistry in the rat show that the peripheral hearing function and morphology of the organ of Corti are normal. We conclude that the tubulin mutation severely impairs the central hearing pathway most probably by progressive central white matter degeneration. Hearing function might be affected in a significant fraction of patients with H-ABC; therefore, screening for auditory function should be done on patients with tubulinopathies to evaluate hearing support therapies.


Assuntos
Deficiências do Desenvolvimento/genética , Distúrbios Distônicos/genética , Perda Auditiva Neurossensorial/genética , Tubulina (Proteína)/deficiência , Substituição de Aminoácidos , Animais , Percepção Auditiva , Pré-Escolar , Núcleo Coclear/patologia , Doenças Desmielinizantes/genética , Modelos Animais de Doenças , Orelha Interna/fisiopatologia , Potenciais Evocados Auditivos , Feminino , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Colículos Inferiores/patologia , Masculino , Mutação de Sentido Incorreto , Bainha de Mielina/patologia , Mutação Puntual , Ratos , Ratos Mutantes , Ratos Sprague-Dawley , Tubulina (Proteína)/genética
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