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1.
Artigo em Inglês | MEDLINE | ID: mdl-38826096

RESUMO

BACKGROUND: Corticobasal syndrome is a clinical diagnosis and common pathological causes are corticobasal degeneration, progressive supranuclear palsy and Alzheimer's disease. OBJECTIVES: We would like to highlight a rare but important differential of corticobasal syndrome. METHODS: A 78-year-old female had a 4-year history of predominantly right-hand rest tremor, worsening of handwriting but no change in cognition. The clinical examination showed right upper limb postural and kinetic tremor, mild wrist rigidity and reduced amplitude of right-sided finger tapping. She was initially diagnosed as idiopathic Parkinson's disease. Five years after onset of symptoms, she demonstrated bilateral myoclonic jerks and right upper limb dystonic posturing. She could not copy movements with the right hand. The magnetic resonance imaging (MRI) revealed disproportionate atrophy in the parietal lobes bilaterally. The clinical diagnosis was changed to probable corticobasal syndrome. She passed away 11 years from onset of symptoms at the age of 85 years. She underwent a post-mortem. RESULTS: The anterior and posterior frontal cortex, anterior cingulate, temporal neocortex, hippocampus and amygdaloid complex demonstrated considerable tau-related pathology consisting of a dense background of neuropil threads, and rounded, paranuclear neuronal inclusions consistent with Pick bodies. The immunostaining for three microtubule binding domain repeats (3R) tau performed on sections from the frontal and temporal lobes, basal ganglia and midbrain highlighted several inclusions whilst no 4R tau was observed. She was finally diagnosed with Pick's disease. CONCLUSIONS: Pick's disease can rarely present with clinical features of corticobasal syndrome.

2.
Pathogens ; 13(5)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38787244

RESUMO

Helicobacter pylori is a gastric oncopathogen that infects over half of the world's human population. It is a Gram-negative, microaerophilic, helix-shaped bacterium that is equipped with flagella, which provide high motility. Colonization of the stomach is asymptomatic in up to 90% of people but is a recognized risk factor for developing various gastric disorders such as gastric ulcers, gastric cancer and gastritis. Invasion of the human stomach occurs via numerous virulence factors such as CagA and VacA. Similarly, outer membrane proteins (OMPs) play an important role in H. pylori pathogenicity as a means to adapt to the epithelial environment and thereby facilitate infection. While some OMPs are porins, others are adhesins. The epithelial cell receptors SabA, BabA, AlpA, OipA, HopQ and HopZ have been extensively researched to evaluate their epidemiology, structure, role and genes. Moreover, numerous studies have been performed to seek to understand the complex relationship between these factors and gastric diseases. Associations exist between different H. pylori virulence factors, the co-expression of which appears to boost the pathogenicity of the bacterium. Improved knowledge of OMPs is a major step towards combatting this global disease. Here, we provide a current overview of different H. pylori OMPs and discuss their pathogenicity, epidemiology and correlation with various gastric diseases.

4.
Nature ; 629(8011): 283, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38714816

Assuntos
Cidades , Livros , Humanos
5.
Cureus ; 16(3): e55735, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38586638

RESUMO

Background and objective Sizing on digital films is important for implants and planning deformity correction. CT is the most accurate digital measurement method. We use a 1-inch ball bearing (cost: $1) to size our long-leg standing films (LLSFs) when planning deformity correction. In this study, we aimed to assess the accuracy of digital measurements calibrated by this method. Methods We conducted An IRB-approved study involving 25 patients having both an LLSF with a 1-inch ball bearing taped to the inner mid-thigh and a CT scanogram. The longest distance in the axial cut of the bilateral ankle, knee, and femoral heads of the CT images were compared to the same anatomic locations on LLSFs calibrated with the ball bearing using the online digital planning software DetroitBonesetter (DBS) and measurements from our Picture Archiving Communication Software (PACS). Five observers performed each measurement. Results The average measurement differences between the gold standard CT scan and LLSFs calibrated with DBS were as follows: 0.110 ± 0.432 mm (femoral head); 2.173 ± 0.0619 mm (knee); and 3.671 ± 0.30 mm (ankle). In PACS, they were as follows: 5.470 ± 0.381 mm (femoral head); 6.248 ± 0.712 mm (knee); and 1.806 ± 0.548 mm (ankle). The intraclass correlation coefficient for 600 measurements by five observers was 0.972. Conclusions The $1 ball-bearing sizing on DBS using LLSFs provides accuracy to <1 mm for the femoral head, 2 mm at the knee, and 3.7 mm at the ankle. It was significantly better than the PACS system for both the femoral head and knee (<0.001), while PACS was better at the ankle (<0.001).

6.
Nature ; 628(8008): 496, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38580822
7.
Sci Signal ; 17(834): eadj6603, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687825

RESUMO

The localization, number, and function of postsynaptic AMPA-type glutamate receptors (AMPARs) are crucial for synaptic plasticity, a cellular correlate for learning and memory. The Hippo pathway member WWC1 is an important component of AMPAR-containing protein complexes. However, the availability of WWC1 is constrained by its interaction with the Hippo pathway kinases LATS1 and LATS2 (LATS1/2). Here, we explored the biochemical regulation of this interaction and found that it is pharmacologically targetable in vivo. In primary hippocampal neurons, phosphorylation of LATS1/2 by the upstream kinases MST1 and MST2 (MST1/2) enhanced the interaction between WWC1 and LATS1/2, which sequestered WWC1. Pharmacologically inhibiting MST1/2 in male mice and in human brain-derived organoids promoted the dissociation of WWC1 from LATS1/2, leading to an increase in WWC1 in AMPAR-containing complexes. MST1/2 inhibition enhanced synaptic transmission in mouse hippocampal brain slices and improved cognition in healthy male mice and in male mouse models of Alzheimer's disease and aging. Thus, compounds that disrupt the interaction between WWC1 and LATS1/2 might be explored for development as cognitive enhancers.


Assuntos
Hipocampo , Peptídeos e Proteínas de Sinalização Intracelular , Plasticidade Neuronal , Fosfoproteínas , Proteínas Serina-Treonina Quinases , Receptores de AMPA , Animais , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Masculino , Humanos , Receptores de AMPA/metabolismo , Receptores de AMPA/genética , Camundongos , Plasticidade Neuronal/fisiologia , Hipocampo/metabolismo , Via de Sinalização Hippo , Serina-Treonina Quinase 3 , Transdução de Sinais , Memória/fisiologia , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Fator de Crescimento de Hepatócito/metabolismo , Camundongos Endogâmicos C57BL , Doença de Alzheimer/metabolismo , Fosforilação , Neurônios/metabolismo
8.
Lancet Neurol ; 23(5): 487-499, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631765

RESUMO

BACKGROUND: Pick's disease is a rare and predominantly sporadic form of frontotemporal dementia that is classified as a primary tauopathy. Pick's disease is pathologically defined by the presence in the frontal and temporal lobes of Pick bodies, composed of hyperphosphorylated, three-repeat tau protein, encoded by the MAPT gene. MAPT has two distinct haplotypes, H1 and H2; the MAPT H1 haplotype is the major genetic risk factor for four-repeat tauopathies (eg, progressive supranuclear palsy and corticobasal degeneration), and the MAPT H2 haplotype is protective for these disorders. The primary aim of this study was to evaluate the association of MAPT H2 with Pick's disease risk, age at onset, and disease duration. METHODS: In this genetic association study, we used data from the Pick's disease International Consortium, which we established to enable collection of data from individuals with pathologically confirmed Pick's disease worldwide. For this analysis, we collected brain samples from individuals with pathologically confirmed Pick's disease from 35 sites (brainbanks and hospitals) in North America, Europe, and Australia between Jan 1, 2020, and Jan 31, 2023. Neurologically healthy controls were recruited from the Mayo Clinic (FL, USA, or MN, USA between March 1, 1998, and Sept 1, 2019). For the primary analysis, individuals were directly genotyped for the MAPT H1-H2 haplotype-defining variant rs8070723. In a secondary analysis, we genotyped and constructed the six-variant-defined (rs1467967-rs242557-rs3785883-rs2471738-rs8070723-rs7521) MAPT H1 subhaplotypes. Associations of MAPT variants and MAPT haplotypes with Pick's disease risk, age at onset, and disease duration were examined using logistic and linear regression models; odds ratios (ORs) and ß coefficients were estimated and correspond to each additional minor allele or each additional copy of the given haplotype. FINDINGS: We obtained brain samples from 338 people with pathologically confirmed Pick's disease (205 [61%] male and 133 [39%] female; 338 [100%] White) and 1312 neurologically healthy controls (611 [47%] male and 701 [53%] female; 1312 [100%] White). The MAPT H2 haplotype was associated with increased risk of Pick's disease compared with the H1 haplotype (OR 1·35 [95% CI 1·12 to 1·64], p=0·0021). MAPT H2 was not associated with age at onset (ß -0·54 [95% CI -1·94 to 0·87], p=0·45) or disease duration (ß 0·05 [-0·06 to 0·16], p=0·35). Although not significant after correcting for multiple testing, associations were observed at p less than 0·05: with risk of Pick's disease for the H1f subhaplotype (OR 0·11 [0·01 to 0·99], p=0·049); with age at onset for H1b (ß 2·66 [0·63 to 4·70], p=0·011), H1i (ß -3·66 [-6·83 to -0·48], p=0·025), and H1u (ß -5·25 [-10·42 to -0·07], p=0·048); and with disease duration for H1x (ß -0·57 [-1·07 to -0·07], p=0·026). INTERPRETATION: The Pick's disease International Consortium provides an opportunity to do large studies to enhance our understanding of the pathobiology of Pick's disease. This study shows that, in contrast to the decreased risk of four-repeat tauopathies, the MAPT H2 haplotype is associated with an increased risk of Pick's disease in people of European ancestry. This finding could inform development of isoform-related therapeutics for tauopathies. FUNDING: Wellcome Trust, Rotha Abraham Trust, Brain Research UK, the Dolby Fund, Dementia Research Institute (Medical Research Council), US National Institutes of Health, and the Mayo Clinic Foundation.


Assuntos
Doença de Pick , Tauopatias , Feminino , Humanos , Masculino , Estudos de Associação Genética , Haplótipos , Doença de Pick/genética , Proteínas tau/genética
9.
Nature ; 628(8009): 715, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38641724
10.
JAMA Netw Open ; 7(4): e244278, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38587847

RESUMO

Importance: Patients with stage IV non-small cell lung cancer (NSCLC) experience substantial morbidity and mortality. Contact days (ie, the number of days with health care contact outside the home) measure how much of a person's life is consumed by health care, yet little is known about patterns of contact days for patients with NSCLC. Objective: To describe the trajectories of contact days in patients with stage IV NSCLC and how trajectories vary by receipt of cancer-directed treatment in routine practice. Design, Setting, and Participants: A retrospective, population-based decedent cohort study was conducted in Ontario, Canada. Participants included adults aged 20 years or older who were diagnosed with stage IV NSCLC (January 1, 2014, to December 31, 2017) and died (January 1, 2014, to December 31, 2019); there was a maximum 2-year follow-up. Data analysis was conducted from February 22 to August 16, 2023. Exposure: Systemic cancer-directed therapy (yes or no) and type of therapy (chemotherapy vs immunotherapy vs targeted therapy). Main Outcomes and Measures: Contact days (days with health care contact, outpatient or institution-based, outside the home) were identified through administrative data. The weekly percentage of contact days and fitted models with cubic splines were quantified to describe trajectories from diagnosis until death. Results: A total of 5785 decedents with stage IV NSCLC were included (median age, 70 [IQR 62-77] years; 3108 [53.7%] were male, and 1985 [34.3%] received systemic therapy). The median overall survival was 108 (IQR, 49-426) days, median contact days were 36 (IQR, 21-62), and the median percentage that were contact days was 33.3%. A median of 5 (IQR, 2-10) days were spent with specialty palliative care. Patients who did not receive systemic therapy had a median overall survival of 66 (IQR, 34-130) days and median contact days of 28 (IQR, 17-44), of which a median of 5 (IQR, 2-9) days were spent with specialty palliative care. Overall and for subgroups, normalized trajectories followed a U-shaped distribution: contact days were most frequent immediately after diagnosis and before death. Patients who received targeted therapy had the lowest contact day rate during the trough (10.6%; vs immunotherapy, 15.4%; vs chemotherapy, 17.7%). Conclusions and Relevance: In this cohort study, decedents with stage IV NSCLC had a median survival in the order of 3.5 months and spent 1 in every 3 days alive interacting with the health care system outside the home. These results highlight the need to better support patients and care partners, benchmark appropriateness, and improve care delivery.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Humanos , Masculino , Idoso , Feminino , Carcinoma Pulmonar de Células não Pequenas/terapia , Estudos de Coortes , Estudos Retrospectivos , Neoplasias Pulmonares/terapia , Pacientes Ambulatoriais , Atenção à Saúde , Ontário/epidemiologia
11.
Public Health Pract (Oxf) ; 7: 100486, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38495538

RESUMO

The commonly heard aphorism about history repeating itself suggests an endless cycle of recurring events. However, George Santayana offered a similar sentiment when he said, "Those who do not learn from history are doomed to repeat it". This emphasises that the responsibility for the recurrence of events lies not with history itself, but with humanity. It underscores that if we desire change, it is our responsibility to initiate it, rather than attributing it to external forces such as fate, luck, or time. With this thought in mind, here we offer a narrative view from sub-Saharan Africa, focusing primarily on our own experiences in Nigeria and Uganda, on what harsh lessons can be learnt from the COVID-19 pandemic regarding emergency preparedness to respond effectively to the next major infectious disease outbreak. Four strategies are suggested, the implementation of which may contribute substantially to safeguarding against an experience similar to the catastrophic public health, social and economic costs borne by African nations during COVID-19 and in its immediate aftermath.

12.
Front Cell Neurosci ; 18: 1321682, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469353

RESUMO

Mature oligodendrocytes (OLG) are the myelin-forming cells of the central nervous system. Recent work has shown a dynamic role for these cells in the plasticity of neural circuits, leading to a renewed interest in voltage-sensitive currents in OLG. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and their respective current (Ih) were recently identified in mature OLG and shown to play a role in regulating myelin length. Here we provide a biochemical and electrophysiological characterization of HCN channels in cells of the oligodendrocyte lineage. We observed that mice with a nonsense mutation in the Hcn2 gene (Hcn2ap/ap) have less white matter than their wild type counterparts with fewer OLG and fewer oligodendrocyte progenitor cells (OPCs). Hcn2ap/ap mice have severe motor impairments, although these deficits were not observed in mice with HCN2 conditionally eliminated only in oligodendrocytes (Cnpcre/+; Hcn2F/F). However, Cnpcre/+; Hcn2F/F mice develop motor impairments more rapidly in response to experimental autoimmune encephalomyelitis (EAE). We conclude that HCN2 channels in OLG may play a role in regulating metabolism.

13.
Nat Commun ; 15(1): 2635, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528004

RESUMO

High levels of proinflammatory cytokines induce neurotoxicity and catalyze inflammation-driven neurodegeneration, but the specific release mechanisms from microglia remain elusive. Here we show that secretory autophagy (SA), a non-lytic modality of autophagy for secretion of vesicular cargo, regulates neuroinflammation-mediated neurodegeneration via SKA2 and FKBP5 signaling. SKA2 inhibits SA-dependent IL-1ß release by counteracting FKBP5 function. Hippocampal Ska2 knockdown in male mice hyperactivates SA resulting in neuroinflammation, subsequent neurodegeneration and complete hippocampal atrophy within six weeks. The hyperactivation of SA increases IL-1ß release, contributing to an inflammatory feed-forward vicious cycle including NLRP3-inflammasome activation and Gasdermin D-mediated neurotoxicity, which ultimately drives neurodegeneration. Results from protein expression and co-immunoprecipitation analyses of male and female postmortem human brains demonstrate that SA is hyperactivated in Alzheimer's disease. Overall, our findings suggest that SKA2-regulated, hyperactive SA facilitates neuroinflammation and is linked to Alzheimer's disease, providing mechanistic insight into the biology of neuroinflammation.


Assuntos
Doença de Alzheimer , Autofagia , Proteínas Cromossômicas não Histona , Proteína 3 que Contém Domínio de Pirina da Família NLR , Doenças Neuroinflamatórias , Animais , Feminino , Humanos , Masculino , Camundongos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Autofagia/genética , Proteínas Cromossômicas não Histona/metabolismo , Citocinas/metabolismo , Inflamassomos/metabolismo , Microglia/metabolismo , Doenças Neuroinflamatórias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
14.
J Alzheimers Dis ; 98(4): 1457-1466, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38552117

RESUMO

Background: While mid-life hypertension represents a risk factor for the development of Alzheimer's disease (AD), the risk after the age of 65 is less certain. Establishing relationships between late life hypertension and the pathological changes of AD could be crucial in understanding the relevance of blood pressure as a risk factor for this disorder. Objective: We investigated associations between self-reported late-life hypertension, cognitive status and AD pathology at death. The impact of antihypertensive medication was also examined. Methods: Using the Cornell Medical Index questionnaire, we ascertained whether participants had ever reported hypertension. We also noted use of antihypertensive medication. The donated brains of 108 individuals were assessed for AD pathology using consensus guidelines. Statistical analysis aimed to elucidate relationships between hypertension and AD pathology. Results: We found no associations between self-reported hypertension and cognitive impairment at death. However, those with hypertension were significantly more likely to exhibit lower levels of AD pathology as measured by Thal phase, Braak stage, CERAD score, and NIA-AA criteria-even after controlling for sex, level of education and presence of APOEɛ4 allele(s). No significant associations could be found when examining use of antihypertensive medications. Conclusions: Our findings suggest that late-life hypertension is associated with less severe AD pathology. We postulate that AD pathology may be promoted by reduced cerebral blood flow.


Assuntos
Doença de Alzheimer , Hipertensão , Humanos , Doença de Alzheimer/patologia , Autorrelato , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Cognição
15.
Nat Commun ; 15(1): 2571, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519467

RESUMO

Isoprene is a key trace component of the atmosphere emitted by vegetation and other organisms. It is highly reactive and can impact atmospheric composition and climate by affecting the greenhouse gases ozone and methane and secondary organic aerosol formation. Marine fluxes are poorly constrained due to the paucity of long-term measurements; this in turn limits our understanding of isoprene cycling in the ocean. Here we present the analysis of isoprene concentrations in the atmosphere measured across the Southern Ocean over 4 months in the summertime. Some of the highest concentrations ( >500 ppt) originated from the marginal ice zone in the Ross and Amundsen seas, indicating the marginal ice zone is a significant source of isoprene at high latitudes. Using the United Kingdom Earth System Model we show that current estimates of sea-to-air isoprene fluxes underestimate observed isoprene by a factor >20. A daytime source of isoprene is required to reconcile models with observations. The model presented here suggests such an increase in isoprene emissions would lead to >8% decrease in the hydroxyl radical in regions of the Southern Ocean, with implications for our understanding of atmospheric oxidation and composition in remote environments, often used as proxies for the pre-industrial atmosphere.

16.
Nature ; 627(8004): 487, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38491223
17.
Nature ; 627(8003): 264, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38429505
18.
Risk Manag Healthc Policy ; 17: 505-511, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481394

RESUMO

Four years after the first case of COVID-19, the world is still determining how best to prevent and control the long-term effects of SARS-CoV-2 infection. Non-pharmaceutical interventions (NPIs) were employed at the start of the pandemic as the only available options, prior to effective vaccines and antiviral agents. The World Health Organization recommended dual vaccination for 70% worldwide as the threshold for a return to "normal" community life. Immunization rates needed to increase in all global regions, irrespective of socioeconomic status, necessitating more equitable access. During the pandemic, wealthier countries hoarded vaccine supplies even when their citizens were immunized. This highlights the already enormous difficulties in healthcare provision faced by low-income sub-Saharan African countries, which remain at risk as industrialized nations have progressed to a post-pandemic era. Thus, in addition to redoubling vaccination efforts public health policymakers should consider ongoing and future use of NPIs. In this narrative account, we advocate that various NPI practices should not be shelved; rather, more research is needed to evaluate their impact in parallel with booster vaccination. This especially applies to so-called "long COVID". Lessons learned from implementing best practices in resource-limited settings should be incorporated into preparedness guidelines for future infectious disease outbreaks.

20.
Nature ; 627(8002): 28, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38374389
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