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Streptococcus suis is a bacterium of clinical importance in diverse animal hosts including companion animals and humans. Companion animals are closely associated in the living environment of humans and are potential reservoirs for zoonotic pathogens. Given the zoonotic potential of S. suis, it is crucial to determine whether this bacterium is present among the companion animal population. This study aimed to detect Streptococcus suis in companion animals namely cats and dogs of the central west coast of Peninsular Malaysia and further characterize the positive isolates via molecular and genomic approach. The detection of S. suis was done via bacterial isolation and polymerase chain reaction assay of gdh and recN gene from oral swabs. Characterization was done by multiplex PCR serotyping, as well as muti-locus sequence typing, AMR gene prediction, MGE identification and phylogenomic analysis on whole genome sequence acquired from Illumina and Oxford Nanopore sequencing. Among the 115 samples, PCR assay detected 2/59 of the cats were positive for S. suis serotype 8 while all screened dog samples were negative. This study further described the first complete whole genome of S. suis strain SS/UPM/MY/F001 isolated from the oral cavity of a companion cat. Genomic analysis revealed a novel strain of S. suis having a unique MLST profile and antimicrobial resistance genes of mefA, msrD, patA, patB and vanY. Mobile genetic elements were described, and pathogenic determinants matched to human and swine strains were identified. Phylogenetic tree analysis on the core genome alignment revealed strain SS/UPM/MY/F001 was distinct from other S. suis strains. This study provided insight into the detection and genomic features of the S. suis isolate of a companion cat and highlighted its potential for antimicrobial resistance and pathogenicity.
Assuntos
Doenças do Gato , Doenças do Cão , Filogenia , Infecções Estreptocócicas , Streptococcus suis , Sequenciamento Completo do Genoma , Gatos , Animais , Streptococcus suis/genética , Streptococcus suis/isolamento & purificação , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/transmissão , Doenças do Gato/microbiologia , Cães , Doenças do Cão/microbiologia , Malásia , Animais de Estimação/microbiologia , Farmacorresistência Bacteriana/genética , Zoonoses/microbiologia , Zoonoses/transmissão , Tipagem de Sequências Multilocus , Genoma Bacteriano , Antibacterianos/farmacologia , Humanos , Zoonoses Bacterianas/microbiologia , Zoonoses Bacterianas/transmissãoRESUMO
PURPOSE: To compare the outcome of indirect inguinal hernias repaired by using single-port laparoscopic percutaneous internal ring suture (SPIRS) between the pediatric and adult females. METHODS: The medical records of females who were clinically assessed to have inguinal hernia from Oct. 2016 to May 2022 were reviewed. Patients who received laparoscopy for the diagnosis of the hernia type and customized treatment according to their hernia type were included, while those who chose other operation methods initially were excluded. The patients were divided into the adult and pediatric groups based on their age. The demographic characteristics, hernia types, operation durations, and outcomes were analyzed between these two groups. RESULTS: A total of 65 adults and 60 children were included in this study. The median age was 38 years. (range: 23-88) for group A and 3 years (range: 0.1-16) for group P. Indirect hernias were present in 85% of adults and 100% of children. All the indirect hernias were repaired by SPIRS uneventfully. Incidence of contralateral patent processus vaginalis was 24% in adults and 50% in children (p = 0.016). The average operation time was 22/46 min (one/two sides) for the adults and 9/15 min (one/two sides) for the pediatrics (p < 0.010 for both). The overall complication rates were 5.4% and 3.3% for the adult and pediatric group respectively (p = 0.106). No recurrence was observed in the pediatric group, but two adults experienced recurrence and another had chronic postoperative inguinal pain, necessitating reoperation. The mean follow-up period was 38.6 ± 15.4 months for adults and 42.8 ± 18.9 months for children (p = 0.198). CONCLUSION: Our results support that the pathogenesis of indirect inguinal hernia for the female adults is due to the non-obliteration of a congenital processus vaginalis. Tailored treatment of the female IIH by using single-port laparoscopic percutaneous internal ring suture may be an alternative for the management of female IHs.
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Hérnia Inguinal , Herniorrafia , Laparoscopia , Técnicas de Sutura , Humanos , Hérnia Inguinal/cirurgia , Feminino , Laparoscopia/métodos , Laparoscopia/efeitos adversos , Adulto , Herniorrafia/métodos , Herniorrafia/efeitos adversos , Criança , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Pré-Escolar , Adolescente , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Duração da Cirurgia , Lactente , Fatores Etários , Recidiva , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologiaRESUMO
BACKGROUND: In Taiwan, sequence type (ST) 239 and ST59 were two major clones among meticillin-resistant Staphylococcus aureus (MRSA) clinical isolates in the past two decades. USA300 (ST8) prevailed in the Americas but not in outside areas. Recently USA300 (ST8) emerged and was increasingly identified in Taiwan; we thus conducted an island-wide study to explore the role of USA300 among MRSA isolates. METHODS: One hundred MRSA bloodstream isolates identified in 2020 from each of the six participating hospitals in Taiwan were collected and characterized. The first 10 ST8 isolates from each hospital were further analysed by whole-genome sequencing. RESULTS: Of the 590 confirmed MRSA isolates, a total of 22 pulsotypes and 21 STs were identified. The strain of pulsotype AI/ST8 was the most common lineage identified, accounting for 187 isolates (31.7%) and dominating in five of six hospitals, followed by pulsotype A/ST239 (14.7%), pulsotype C/ST59 (13.9%) and pulsotype D/ST59 (9.2%). Of the 187 pulsotype AI/ST8 isolates, 184 isolates were characterized as USA300 and clustered in three major sub-pulsotypes, accounting for 78%. Ninety per cent of the 60 ST8 isolates for whole-genome sequencing were clustered in three major clades. CONCLUSIONS: In 2020, USA300 became the most common clone of MRSA in Taiwan, accounting for >30% of MRSA bloodstream isolates island wide. Most of USA300 isolates circulating in Taiwan might have been imported on multiple occasions and evolved into at least three successful local clades. MRSA USA300 has successfully established its role in Taiwan, an area outside of the Americas.
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Genótipo , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Sequenciamento Completo do Genoma , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Taiwan/epidemiologia , Humanos , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Epidemiologia Molecular , Hospitais/estatística & dados numéricos , Bacteriemia/microbiologia , Bacteriemia/epidemiologia , Tipagem MolecularRESUMO
BACKGROUND: Pharmacological ascorbate (intravenous delivery reaching plasma concentrations ≈ 20 mM; P-AscH-) has emerged as a promising therapeutic strategy for glioblastoma. Recently, a single-arm phase 2 clinical trial demonstrated a significant increase in overall survival when P-AscH- was combined with temozolomide and radiotherapy. As P-AscH- relies on iron-dependent mechanisms, this study aimed to assess the predictive potential of both molecular and imaging-based iron-related markers to enhance the personalization of P-AscH- therapy in glioblastoma participants. METHODS: Participants (n = 55) with newly diagnosed glioblastoma were enrolled in a phase 2 clinical trial conducted at the University of Iowa (NCT02344355). Tumor samples obtained during surgical resection were processed and stained for transferrin receptor and ferritin heavy chain expression. A blinded pathologist performed pathological assessment. Quantitative susceptibility mapping (QSM) measures were obtained from pre-radiotherapy MRI scans following maximal safe surgical resection. Circulating blood iron panels were evaluated prior to therapy through the University of Iowa Diagnostic Laboratory. RESULTS: Through univariate analysis, a significant inverse association was observed between tumor transferrin receptor expression and overall and progression-free survival. QSM measures exhibited a significant, positive association with progression-free survival. Subjects were actively followed until disease progression and then were followed through chart review or clinical visits for overall survival. CONCLUSIONS: This study analyzes iron-related biomarkers in the context of P-AscH- therapy for glioblastoma. Integrating molecular, systemic, and imaging-based markers offers a multifaceted approach to tailoring treatment strategies, thereby contributing to improved patient outcomes and advancing the field of glioblastoma therapy.
HIGHLIGHTS: Pharmacological ascorbate shows significant promise to enhance glioblastoma clinical outcomes. Transferrin receptor and ferritin heavy chain expression represent potential molecular markers to predict pharmacological ascorbate treatment response. Quantitative Susceptibility Mapping is an MRI technique that can serve as a non-invasive marker of iron metabolism to evaluate progression-free survival. Systemic iron metabolic markers are readily available diagnostic tests that can potentially be used to prognosticate overall survival.
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Antineoplásicos , Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagem , Glioblastoma/tratamento farmacológico , Ferro , Temozolomida/uso terapêutico , Antineoplásicos/uso terapêutico , Biomarcadores , Receptores da Transferrina , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/cirurgiaRESUMO
@#Streptococcus suis is a bacterium of clinical importance in diverse animal hosts including companion animals and humans. Companion animals are closely associated in the living environment of humans and are potential reservoirs for zoonotic pathogens. Given the zoonotic potential of S. suis, it is crucial to determine whether this bacterium is present among the companion animal population. This study aimed to detect Streptococcus suis in companion animals namely cats and dogs of the central west coast of Peninsular Malaysia and further characterize the positive isolates via molecular and genomic approach. The detection of S. suis was done via bacterial isolation and polymerase chain reaction assay of gdh and recN gene from oral swabs. Characterization was done by multiplex PCR serotyping, as well as muti-locus sequence typing, AMR gene prediction, MGE identification and phylogenomic analysis on whole genome sequence acquired from Illumina and Oxford Nanopore sequencing. Among the 115 samples, PCR assay detected 2/59 of the cats were positive for S. suis serotype 8 while all screened dog samples were negative. This study further described the first complete whole genome of S. suis strain SS/UPM/MY/F001 isolated from the oral cavity of a companion cat. Genomic analysis revealed a novel strain of S. suis having a unique MLST profile and antimicrobial resistance genes of mefA, msrD, patA, patB and vanY. Mobile genetic elements were described, and pathogenic determinants matched to human and swine strains were identified. Phylogenetic tree analysis on the core genome alignment revealed strain SS/UPM/MY/F001 was distinct from other S. suis strains. This study provided insight into the detection and genomic features of the S. suis isolate of a companion cat and highlighted its potential for antimicrobial resistance and pathogenicity.
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Porcine circovirus type 4 (PCV4) is the newest member in the porcine circovirus family, first reported in 2020. To date, the presence of PCV4 has only been reported in China, South Korea and most recently in Thailand. Detection of PCV4 have been reported in various production stages of pigs from piglets, finishers to sows; associated with a myriad of clinical manifestations including porcine dermatitis and nephropathy syndrome (PDNS), postweaning multisystemic wasting syndrome (PMWS), respiratory, enteric and neurological diseases. While successful virus isolation and culture has yet to be reported, pathogenicity of PCV4 has been demonstrated through infectious clone studies. The objective of this study is to investigate the presence of PCV4 in Malaysian porcine population to update the epidemiology of porcine circoviruses in Malaysia. A total of 49 samples from commercial intensive pig farms, abattoir and wild boar population were subjected to conventional polymerase chain reaction assay to detect PCV4 capsid (cap) genome. Resulting cap nucleotide sequences were analyzed for maximum likelihood phylogeny relationship. Results revealed that PCV4 is present in Peninsular Malaysia at a molecular prevalence of 4.08% (2 / 49 samples). Both PCV4 positive samples originated from clinically healthy finishers. Malaysian PCV4 strains were classified as genotype PCV4b, and were found to be phylogenetically distinct from the China, South Korea and Thailand strains. With this latest update of the novel PCV4 in Malaysia, it is clear that more attention needs to be given to the investigation of novel porcine circoviruses (PCV) and management of PCV diseases.
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Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Suínos , Animais , Doenças dos Suínos/epidemiologia , Circovirus/genética , Malásia/epidemiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/genética , Sequência de Bases , Proteínas do Capsídeo/genética , FilogeniaRESUMO
Background: Genetic study of late-onset Alzheimer's disease (AD) reveals that a rare Arginine-to-Histamine mutation at amino acid residue 47 (R47H) in Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) results in increased disease risk. TREM2 plays critical roles in regulating microglial response to amyloid plaques in AD, leading to their clustering and activation surrounding the plaques. We previously showed that increasing human TREM2 gene dosage exerts neuroprotective effects against AD-related deficits in amyloid depositing mouse models of AD. However, the in vivo effects of the R47H mutation on human TREM2-mediated microglial reprogramming and neuroprotection remains poorly understood. Method: Here we created a BAC transgenic mouse model expressing human TREM2 with the R47H mutation in its cognate genomic context (BAC-TREM2-R47H). Importantly, the BAC used in this study was engineered to delete critical exons of other TREM-like genes on the BAC to prevent confounding effects of overexpressing multiple TREM-like genes. We crossed BAC-TREM2- R47H mice with 5xFAD [1], an amyloid depositing mouse model of AD, to evaluate amyloid pathologies and microglial phenotypes, transcriptomics and in situ expression of key TREM2 -dosage dependent genes. We also compared the key findings in 5xFAD/BAC-TREM2-R47H to those observed in 5xFAD/BAC-TREM2 mice. Result: Both BAC-TREM2 and BAC-TREM2-R47H showed proper expression of three splicing isoforms of TREM2 that are normally found in human. In 5xFAD background, elevated TREM2-R47H gene dosages significantly reduced the plaque burden, especially the filamentous type. The results were consistent with enhanced phagocytosis and altered NLRP3 inflammasome activation in BAC- TREM2-R47H microglia in vitro. However, unlike TREM2 overexpression, elevated TREM2- R47H in 5xFAD failed to ameliorate cognitive and transcriptomic deficits. In situ analysis of key TREM2 -dosage dependent genes and microglial morphology uncovered that TREM2-R47H showed a loss-of-function phenotype in reprogramming of plaque-associated microglial reactivity and gene expression in 5xFAD. Conclusion: Our study demonstrated that the AD-risk variant has a previously unknown, mixture of partial and full loss of TREM2 functions in modulating microglial response in AD mouse brains. Together, our new BAC-TREM2-R47H model and prior BAC-TREM2 mice are invaluable resource to facilitate the therapeutic discovery that target human TREM2 and its R47H variant to ameliorate AD and other neurodegenerative disorders.
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Individuals diagnosed with neurodevelopmental conditions such as autism spectrum disorder (ASD; autism) often experience tissue inflammation as well as gastrointestinal dysfunction, yet their underlying causes remain poorly characterised. Notably, the largest components of the body's immune system, including gut-associated lymphoid tissue (GALT), lie within the gastrointestinal tract. A major constituent of GALT in humans comprises secretory lymphoid aggregates known as Peyer's patches that sense and combat constant exposure to pathogens and infectious agents. Essential to the functions of Peyer's patches is its communication with the enteric nervous system (ENS), an intrinsic neural network that regulates gastrointestinal function. Crosstalk between these tissues contribute to the microbiota-gut-brain axis that altogether influences mood and behaviour. Increasing evidence further points to a critical role for this signalling axis in neurodevelopmental homeostasis and disease. Notably, while the neuroimmunomodulatory functions for Peyer's patches are increasingly better understood, functions for tissues of analogous function, such as caecal patches, remain less well characterised. Here, we compare the structure, function and development of Peyer's patches, as well as caecal and appendix patches in humans and model organisms including mice to highlight the roles for these essential tissues in health and disease. We propose that perturbations to GALT function may underlie inflammatory disorders and gastrointestinal dysfunction in neurodevelopmental conditions such as autism.
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Transtorno do Espectro Autista , Humanos , Camundongos , Animais , Nódulos Linfáticos AgregadosRESUMO
@#Porcine circovirus type 4 (PCV4) is the newest member in the porcine circovirus family, first reported in 2020. To date, the presence of PCV4 has only been reported in China, South Korea and most recently in Thailand. Detection of PCV4 have been reported in various production stages of pigs from piglets, finishers to sows; associated with a myriad of clinical manifestations including porcine dermatitis and nephropathy syndrome (PDNS), postweaning multisystemic wasting syndrome (PMWS), respiratory, enteric and neurological diseases. While successful virus isolation and culture has yet to be reported, pathogenicity of PCV4 has been demonstrated through infectious clone studies. The objective of this study is to investigate the presence of PCV4 in Malaysian porcine population to update the epidemiology of porcine circoviruses in Malaysia. A total of 49 samples from commercial intensive pig farms, abattoir and wild boar population were subjected to conventional polymerase chain reaction assay to detect PCV4 capsid (cap) genome. Resulting cap nucleotide sequences were analyzed for maximum likelihood phylogeny relationship. Results revealed that PCV4 is present in Peninsular Malaysia at a molecular prevalence of 4.08% (2 / 49 samples). Both PCV4 positive samples originated from clinically healthy finishers. Malaysian PCV4 strains were classified as genotype PCV4b, and were found to be phylogenetically distinct from the China, South Korea and Thailand strains. With this latest update of the novel PCV4 in Malaysia, it is clear that more attention needs to be given to the investigation of novel porcine circoviruses (PCV) and management of PCV diseases.
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OBJECTIVE: Janus Kinase (JAK) inhibitors have been extensively evaluated for their potential in the management of various diseases. Despite previous research on this topic, there is a lack of bibliometric analysis that summarizes research trends on JAK inhibitors. This study aims to provide a comprehensive overview of the top 100 most frequently cited studies on JAK inhibitors over the last ten years. MATERIALS AND METHODS: The Web of Science database was used to screen and extract relevant studies on JAK inhibitors. The top 100 studies most cited within the JAK inhibitor-related research were identified and evaluated, and various data such as the year of publication, study focus and keywords, author information, and number of citations were extracted and analyzed for further examination. RESULTS: In the top 100 most cited studies of JAK inhibitors, more than 70% of studies focused on the role of JAK inhibitors in disease treatments, with 42% of these studies focused on using JAK inhibitors as treatment for autoimmune diseases and 19 of them focused on the treatment of neoplasms. Time trend analysis revealed that the keywords "tofacitinib", "atopic dermatitis", and "rheumatoid arthritis" were widely mentioned in 2016, while new trends emerged in 2018, with "ruxolitinib" and "baricitinib" being more commonly mentioned. CONCLUSIONS: The top 100 most frequently cited studies on JAK inhibitors focused primarily on the safety and efficacy of these inhibitors in the management of various diseases, particularly inflammatory diseases and neoplasms. The results can serve as a valuable reference for rheumatologists and immunologists interested in the development of JAK inhibitors and expanding future research fields.
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Artrite Reumatoide , Doenças Autoimunes , Inibidores de Janus Quinases , Neoplasias , Humanos , Inibidores de Janus Quinases/uso terapêutico , Inibidores de Janus Quinases/farmacologia , BibliometriaRESUMO
Autism spectrum disorder (ASD; autism) is a prevalent neurodevelopmental disorder associated with changes in gut-brain axis communication. Gastrointestinal (GI) symptoms are experienced by a large proportion of individuals diagnosed with autism. Several mutations associated with autism modify cellular communication via neuronal synapses. It has been suggested that modifications to the enteric nervous system, an intrinsic nervous system of the GI tract, could contribute to GI dysfunction. Changes in gut motility, permeability, and the mucosal barrier as well as shifts in the large population of microbes inhabiting the GI tract could contribute to GI symptoms. Preclinical research has demonstrated that mice expressing the well-studied R451C missense mutation in Nlgn3 gene, which encodes cell adhesion protein neuroligin-3 at neuronal synapses, exhibit GI dysfunction. Specifically, NL3R451C mice show altered colonic motility and faster small intestinal transit. As well as dysmotility, macrophages located within the gut-associated lymphoid tissue of the NL3R451C mouse caecum show altered morphology, suggesting that neuro-inflammation pathways are modified in this model. Interestingly, NL3R451C mice maintained in a shared environment demonstrate fecal microbial dysbiosis indicating a role for the nervous system in regulating gut microbial populations. To better understand host-microbe interactions, further clarification and comparison of clinical and animal model profiles of dysbiosis should be obtained, which in turn will provide better insights into the efforts taken to design personalized microbial therapies. In addition to changes in neurophysiological measures, the mucosal component of the GI barrier may contribute to GI dysfunction more broadly in individuals diagnosed with a wide range of neurological disorders. As the study of GI dysfunction advances to encompass multiple components of the gut-brain-microbiota axis, findings will help understand future directions such as microbiome engineering and optimisation of the mucosal barrier for health.
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Transtorno do Espectro Autista , Gastroenteropatias , Microbiota , Camundongos , Animais , Transtorno do Espectro Autista/genética , Eixo Encéfalo-Intestino , Disbiose/metabolismo , Gastroenteropatias/genética , Gastroenteropatias/tratamento farmacológico , Encéfalo/metabolismoRESUMO
Nuclear fusion is one of the most attractive alternatives to carbon-dependent energy sources1. Harnessing energy from nuclear fusion in a large reactor scale, however, still presents many scientific challenges despite the many years of research and steady advances in magnetic confinement approaches. State-of-the-art magnetic fusion devices cannot yet achieve a sustainable fusion performance, which requires a high temperature above 100 million kelvin and sufficient control of instabilities to ensure steady-state operation on the order of tens of seconds2,3. Here we report experiments at the Korea Superconducting Tokamak Advanced Research4 device producing a plasma fusion regime that satisfies most of the above requirements: thanks to abundant fast ions stabilizing the core plasma turbulence, we generate plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. A low plasma density combined with a moderate input power for operation is key to establishing this regime by preserving a high fraction of fast ions. This regime is rarely subject to disruption and can be sustained reliably even without a sophisticated control, and thus represents a promising path towards commercial fusion reactors.
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SETTING: Five referral hospitals, South Korea.OBJECTIVE: To assess epidemiological changes in TB before and during the COVID-19 pandemic.DESIGN: This was a multicentre cohort study of 3,969 patients diagnosed with TB.RESULTS: We analysed 3,453 patients diagnosed with TB prior to the COVID-19 pandemic (January 2016-February 2020) and 516 during the pandemic (March-November 2020). During the pandemic, the number of patients visits declined by 15% from the previous 4-year average, and the number of patients diagnosed with TB decreased by 17%. Patients diagnosed during the pandemic were older than those diagnosed before the pandemic (mean age, 60.2 vs. 56.6 years, P < 0.001). The proportion of patients to have primary TB at a younger age (births after 1980) among those diagnosed with TB was significantly lower during the pandemic than before (17.8% in 2020 vs. 23.5% in 2016, 24.0% in 2017, 22.5% in 2018, 23.5% in 2019; P = 0.005).CONCLUSIONS: The COVID-19 pandemic resulted in a reduction in the number of visits to respiratory departments, leading to fewer patients being diagnosed with TB. However, our results suggest that universal personal preventive measures help to suppress TB transmission in regions with intermediate TB burden.
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COVID-19 , Tuberculose , Humanos , Pessoa de Meia-Idade , Estudos de Coortes , Pandemias , República da Coreia/epidemiologia , SARS-CoV-2 , Tuberculose/epidemiologiaRESUMO
T2* relaxation is an intrinsic magnetic resonance imaging (MRI) parameter that is sensitive to local magnetic field inhomogeneities created by the deposition of endogenous paramagnetic material (e.g. iron). Recent studies suggest that T2* mapping is sensitive to iron oxidation state. In this study, we evaluate the spin state-dependence of T2* relaxation using T2* mapping. We experimentally tested this physical principle using a series of phantom experiments showing that T2* relaxation times are directly proportional to the spin magnetic moment of different transition metals along with their associated magnetic susceptibility. We previously showed that T2* relaxation time can detect the oxidation of Fe2+. In this paper, we demonstrate that T2* relaxation times are significantly longer for the diamagnetic, d10 metal Ga3+, compared to the paramagnetic, d5 metal Fe3+. We also show in a cell culture model that cells supplemented with Ga3+ (S = 0) have a significantly longer relaxation time compared to cells supplemented with Fe3+ (S = 5/2). These data support the hypothesis that dipole-dipole interactions between protons and electrons are driven by the strength of the electron spin magnetic moment in the surrounding environment giving rise to T2* relaxation.
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Imageamento por Ressonância Magnética , Teoria Quântica , Cátions/química , Elétrons , Gálio/química , Peróxido de Hidrogênio/química , Ferro/química , PrótonsRESUMO
In Huntington's disease (HD), the mutant Huntingtin (mHTT) is postulated to mediate template-based aggregation that can propagate across cells. It has been difficult to quantitatively detect such pathological seeding activities in patient biosamples, e.g. cerebrospinal fluids (CSF), and study their correlation with the disease manifestation. Here we developed a cell line expressing a domain-engineered mHTT-exon 1 reporter, which showed remarkably high sensitivity and specificity in detecting mHTT seeding species in HD patient biosamples. We showed that the seeding-competent mHTT species in HD CSF are significantly elevated upon disease onset and with the progression of neuropathological grades. Mechanistically, we showed that mHTT seeding activities in patient CSF could be ameliorated by the overexpression of chaperone DNAJB6 and by antibodies against the polyproline domain of mHTT. Together, our study developed a selective and scalable cell-based tool to investigate mHTT seeding activities in HD CSF, and demonstrated that the CSF mHTT seeding species are significantly associated with certain disease states. This seeding activity can be ameliorated by targeting specific domain or proteostatic pathway of mHTT, providing novel insights into such pathological activities.
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Líquido Cefalorraquidiano/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Proteína Huntingtina/metabolismo , Doença de Huntington/patologia , Chaperonas Moleculares/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Agregação Patológica de Proteínas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Linhagem Celular , Éxons/genética , Feminino , Genes Reporter/genética , Proteínas de Choque Térmico HSP40/genética , Humanos , Proteína Huntingtina/líquido cefalorraquidiano , Proteína Huntingtina/genética , Doença de Huntington/líquido cefalorraquidiano , Doença de Huntington/genética , Microscopia Intravital , Masculino , Pessoa de Meia-Idade , Chaperonas Moleculares/genética , Mutação , Proteínas do Tecido Nervoso/genética , Agregação Patológica de Proteínas/líquido cefalorraquidiano , Agregação Patológica de Proteínas/genética , Domínios Proteicos/genética , Engenharia de Proteínas , Dobramento de ProteínaRESUMO
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare inherited cardiomyopathy characterised by right ventricular dysfunction, ventricular arrhythmias and increased risk of sudden cardiac death. Due to the replacement of myocardium with fibro-fatty and fibrous tissue, patients with ARVC are prone to develop ventricular tachycardia. Histologically, it is often reported as the 'triangle of dysplasia' involving the inflow tract, outflow tract and apex of the right ventricle.2 We describe a 20-years-old patient who collapsed during a futsal match and was subsequently diagnosed to have ARVC with a right ventricular thrombus from cardiac magnetic resonance imaging.
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Displasia Arritmogênica Ventricular Direita/diagnóstico por imagem , Trombose/diagnóstico por imagem , Disfunção Ventricular Direita/fisiopatologia , Displasia Arritmogênica Ventricular Direita/tratamento farmacológico , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Displasia Arritmogênica Ventricular Direita/cirurgia , Humanos , Masculino , Trombose/tratamento farmacológico , Resultado do Tratamento , Disfunção Ventricular Direita/cirurgia , Adulto JovemRESUMO
In S. cerevisiae prophase meiotic chromosomes move by forces generated in the cytoplasm and transduced to the telomere via a protein complex located in the nuclear membrane. We know that chromosome movements require actin cytoskeleton [13,31] and the proteins Ndj1, Mps3, and Csm4. Until recently, the identity of the protein connecting Ndj1-Mps3 with the cytoskeleton components was missing. It was also not known the identity of a cytoplasmic motor responsible for interacting with the actin cytoskeleton and a protein at the outer nuclear envelope. Our recent work [36] identified Mps2 as the protein connecting Ndj1-Mps3 with cytoskeleton components; Myo2 as the cytoplasmic motor that interacts with Mps2; and Cms4 as a regulator of Mps2 and Myo2 interaction and activities (Figure 1). Below we present a model for how Mps2, Csm4, and Myo2 promote chromosome movements by providing the primary connections joining telomeres to the actin cytoskeleton through the LINC complex.
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Cromossomos Fúngicos , Meiose , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Telômero/metabolismo , Citoesqueleto de Actina/metabolismo , Estruturas Cromossômicas , Cromossomos Fúngicos/genética , Cromossomos Fúngicos/metabolismo , Meiose/genética , Modelos Moleculares , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Telômero/genéticaRESUMO
Forward genetic screen, typically performed in invertebrates or mammalian cell lines, has been instrumental in discovering genes essential for neural function. In this issue of Neuron, Wertz et al. (2020) demonstrate the first viral-mediated, genome-wide screen to identify neuroprotective genes in wild-type and Huntington's disease (HD) mouse brains.
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Doença de Huntington , Animais , Morte Celular , Sobrevivência Celular , Camundongos , Neurônios , NeuroproteçãoRESUMO
AIMS: Congenital myasthenic syndromes (CMS) are characterized by muscle weakness, ptosis and episodic apnoea. Mutations affect integral protein components of the neuromuscular junction (NMJ). Here we searched for the genetic basis of CMS in female monozygotic twins. METHODS: We employed whole-exome sequencing for mutation detection and Sanger sequencing for segregation analysis. Immunohistology was done with antibodies against CHD8, rapsyn, ß-catenin (ßCAT) and golgin on fi-bro-blasts, human and mouse muscle. We recorded superresolution images of the NMJ using 3D-structured illumination microscopy. RESULTS: We discovered a spontaneous missense mutation in CHD8 [chr14:g.21,884,051G>A, GRCh37.p11 | c.1732C>T, NM_00117062 | p.(R578C)], the gene encoding chromodomain helicase DNA-binding protein 8. This is the first missense mutation affecting Duplin, the short 110 kDa isoform of CHD8. It is known that CHD8/Duplin negatively regulates ßCAT signalling in the WNT pathway and plays a role in chromatin remodelling. Inactivating CHD8 mutations are associated with autism spectrum disorder and intellectual disability in combination with facial dysmorphism, overgrowth and macrocephalus. No muscle-specific phenotype has been reported to date. Co-immunostaining with rapsyn on human and mouse muscle revealed a strong presence of CHD8 at the NMJ being located towards the sarcoplasmic side of the rapsyn cluster, where it co-localizes with ßCAT. CONCLUSION: We hypothesize CHD8 to have a role in the maintenance of the structural integrity and function of the NMJ. Both patients benefited from treatment with 3,4-diaminopyridine, a reversible blocker of voltage-gated potassium channels at the nerve terminal that prolongs the action potential and increases acetylcholine release.