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1.
Cell ; 183(7): 1785-1800.e26, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33333025

RESUMO

All proteins interact with other cellular components to fulfill their function. While tremendous progress has been made in the identification of protein complexes, their assembly and dynamics remain difficult to characterize. Here, we present a high-throughput strategy to analyze the native assembly kinetics of protein complexes. We apply our approach to characterize the co-assembly for 320 pairs of nucleoporins (NUPs) constituting the ≈50 MDa nuclear pore complex (NPC) in yeast. Some NUPs co-assemble fast via rapid exchange whereas others require lengthy maturation steps. This reveals a hierarchical principle of NPC biogenesis where individual subcomplexes form on a minute timescale and then co-assemble from center to periphery in a ∼1 h-long maturation process. Intriguingly, the NUP Mlp1 stands out as joining very late and associating preferentially with aged NPCs. Our approach is readily applicable beyond the NPC, making it possible to analyze the intracellular dynamics of a variety of multiprotein assemblies.


Assuntos
Substâncias Macromoleculares/metabolismo , Complexos Multiproteicos/metabolismo , Saccharomyces cerevisiae/metabolismo , Coloração e Rotulagem , Bioensaio , Cinética , Modelos Biológicos , Poro Nuclear/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Tempo
2.
Nat Immunol ; 22(1): 74-85, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32999467

RESUMO

T cell immunity is central for the control of viral infections. To characterize T cell immunity, but also for the development of vaccines, identification of exact viral T cell epitopes is fundamental. Here we identify and characterize multiple dominant and subdominant SARS-CoV-2 HLA class I and HLA-DR peptides as potential T cell epitopes in COVID-19 convalescent and unexposed individuals. SARS-CoV-2-specific peptides enabled detection of post-infectious T cell immunity, even in seronegative convalescent individuals. Cross-reactive SARS-CoV-2 peptides revealed pre-existing T cell responses in 81% of unexposed individuals and validated similarity with common cold coronaviruses, providing a functional basis for heterologous immunity in SARS-CoV-2 infection. Diversity of SARS-CoV-2 T cell responses was associated with mild symptoms of COVID-19, providing evidence that immunity requires recognition of multiple epitopes. Together, the proposed SARS-CoV-2 T cell epitopes enable identification of heterologous and post-infectious T cell immunity and facilitate development of diagnostic, preventive and therapeutic measures for COVID-19.


Assuntos
COVID-19/imunologia , Epitopos de Linfócito T/imunologia , Peptídeos/imunologia , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Vacinas Virais/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Reações Cruzadas/imunologia , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Memória Imunológica/imunologia , SARS-CoV-2/fisiologia , Linfócitos T/metabolismo , Vacinas Virais/administração & dosagem
3.
Nature ; 623(7987): 601-607, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37853129

RESUMO

Many bacteria use CRISPR-Cas systems to combat mobile genetic elements, such as bacteriophages and plasmids1. In turn, these invasive elements have evolved anti-CRISPR proteins to block host immunity2,3. Here we unveil a distinct type of CRISPR-Cas Inhibition strategy that is based on small non-coding RNA anti-CRISPRs (Racrs). Racrs mimic the repeats found in CRISPR arrays and are encoded in viral genomes as solitary repeat units4. We show that a prophage-encoded Racr strongly inhibits the type I-F CRISPR-Cas system by interacting specifically with Cas6f and Cas7f, resulting in the formation of an aberrant Cas subcomplex. We identified Racr candidates for almost all CRISPR-Cas types encoded by a diverse range of viruses and plasmids, often in the genetic context of other anti-CRISPR genes5. Functional testing of nine candidates spanning the two CRISPR-Cas classes confirmed their strong immune inhibitory function. Our results demonstrate that molecular mimicry of CRISPR repeats is a widespread anti-CRISPR strategy, which opens the door to potential biotechnological applications6.


Assuntos
Bactérias , Bacteriófagos , Sistemas CRISPR-Cas , Mimetismo Molecular , RNA Viral , Bactérias/genética , Bactérias/imunologia , Bactérias/virologia , Bacteriófagos/genética , Bacteriófagos/imunologia , Biotecnologia/métodos , Biotecnologia/tendências , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/imunologia , Plasmídeos/genética , Prófagos/genética , Prófagos/imunologia , RNA Viral/genética
4.
Nat Immunol ; 17(6): 626-35, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27111143

RESUMO

Innate lymphoid cells (ILCs) are critical mediators of mucosal immunity, and group 1 ILCs (ILC1 cells) and group 3 ILCs (ILC3 cells) have been shown to be functionally plastic. Here we found that group 2 ILCs (ILC2 cells) also exhibited phenotypic plasticity in response to infectious or noxious agents, characterized by substantially lower expression of the transcription factor GATA-3 and a concomitant switch to being ILC1 cells that produced interferon-γ (IFN-γ). Interleukin 12 (IL-12) and IL-18 regulated this conversion, and during viral infection, ILC2 cells clustered within inflamed areas and acquired an ILC1-like phenotype. Mechanistically, these ILC1 cells augmented virus-induced inflammation in a manner dependent on the transcription factor T-bet. Notably, IL-12 converted human ILC2 cells into ILC1 cells, and the frequency of ILC1 cells in patients with chronic obstructive pulmonary disease (COPD) correlated with disease severity and susceptibility to exacerbations. Thus, functional plasticity of ILC2 cells exacerbates anti-viral immunity, which may have adverse consequences in respiratory diseases such as COPD.


Assuntos
Infecções por Haemophilus/imunologia , Haemophilus influenzae/imunologia , Vírus da Influenza A/imunologia , Pulmão/imunologia , Linfócitos/imunologia , Infecções por Orthomyxoviridae/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Células Th1/imunologia , Células Th2/imunologia , Idoso , Animais , Diferenciação Celular , Plasticidade Celular/imunologia , Células Cultivadas , Citocinas/metabolismo , Feminino , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Fenótipo , Fumar/efeitos adversos , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo
5.
Nat Immunol ; 17(6): 636-45, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27111145

RESUMO

Group 2 innate lymphoid cells (ILC2s) secrete type 2 cytokines, which protect against parasites but can also contribute to a variety of inflammatory airway diseases. We report here that interleukin 1ß (IL-1ß) directly activated human ILC2s and that IL-12 induced the conversion of these activated ILC2s into interferon-γ (IFN-γ)-producing ILC1s, which was reversed by IL-4. The plasticity of ILCs was manifested in diseased tissues of patients with severe chronic obstructive pulmonary disease (COPD) or chronic rhinosinusitis with nasal polyps (CRSwNP), which displayed IL-12 or IL-4 signatures and the accumulation of ILC1s or ILC2s, respectively. Eosinophils were a major cellular source of IL-4, which revealed cross-talk between IL-5-producing ILC2s and IL-4-producing eosinophils. We propose that IL-12 and IL-4 govern ILC2 functional identity and that their imbalance results in the perpetuation of type 1 or type 2 inflammation.


Assuntos
Plasticidade Celular , Eosinófilos/imunologia , Imunidade Inata , Interleucina-12/metabolismo , Interleucina-1beta/metabolismo , Interleucina-4/metabolismo , Linfócitos/imunologia , Pólipos Nasais/imunologia , Pneumonia/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Rinite/imunologia , Sinusite/imunologia , Animais , Diferenciação Celular , Células Cultivadas , Feminino , Humanos , Interferon gama/metabolismo , Ativação Linfocitária , Camundongos , Camundongos SCID , Células Th1/imunologia , Equilíbrio Th1-Th2 , Células Th2/imunologia
6.
Nature ; 601(7894): 617-622, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34814158

RESUMO

T cell immunity is central for the control of viral infections. CoVac-1 is a peptide-based vaccine candidate, composed of SARS-CoV-2 T cell epitopes derived from various viral proteins1,2, combined with the Toll-like receptor 1/2 agonist XS15 emulsified in Montanide ISA51 VG, aiming to induce profound SARS-CoV-2 T cell immunity to combat COVID-19. Here we conducted a phase I open-label trial, recruiting 36 participants aged 18-80 years, who received a single subcutaneous CoVac-1 vaccination. The primary end point was safety analysed until day 56. Immunogenicity in terms of CoVac-1-induced T cell response was analysed as the main secondary end point until day 28 and in the follow-up until month 3. No serious adverse events and no grade 4 adverse events were observed. Expected local granuloma formation was observed in all study participants, whereas systemic reactogenicity was absent or mild. SARS-CoV-2-specific T cell responses targeting multiple vaccine peptides were induced in all study participants, mediated by multifunctional T helper 1 CD4+ and CD8+ T cells. CoVac-1-induced IFNγ T cell responses persisted in the follow-up analyses and surpassed those detected after SARS-CoV-2 infection as well as after vaccination with approved vaccines. Furthermore, vaccine-induced T cell responses were unaffected by current SARS-CoV-2 variants of concern. Together, CoVac-1 showed a favourable safety profile and induced broad, potent and variant of concern-independent T cell responses, supporting the presently ongoing evaluation in a phase II trial for patients with B cell or antibody deficiency.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Administração Cutânea , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Feminino , Granuloma/imunologia , Humanos , Imunogenicidade da Vacina , Interferon gama/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/efeitos adversos , Adulto Jovem
7.
J Pathol ; 262(3): 271-288, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38230434

RESUMO

Recent advances in the field of immuno-oncology have brought transformative changes in the management of cancer patients. The immune profile of tumours has been found to have key value in predicting disease prognosis and treatment response in various cancers. Multiplex immunohistochemistry and immunofluorescence have emerged as potent tools for the simultaneous detection of multiple protein biomarkers in a single tissue section, thereby expanding opportunities for molecular and immune profiling while preserving tissue samples. By establishing the phenotype of individual tumour cells when distributed within a mixed cell population, the identification of clinically relevant biomarkers with high-throughput multiplex immunophenotyping of tumour samples has great potential to guide appropriate treatment choices. Moreover, the emergence of novel multi-marker imaging approaches can now provide unprecedented insights into the tumour microenvironment, including the potential interplay between various cell types. However, there are significant challenges to widespread integration of these technologies in daily research and clinical practice. This review addresses the challenges and potential solutions within a structured framework of action from a regulatory and clinical trial perspective. New developments within the field of immunophenotyping using multiplexed tissue imaging platforms and associated digital pathology are also described, with a specific focus on translational implications across different subtypes of cancer. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Biomarcadores Tumorais/genética , Prognóstico , Fenótipo , Reino Unido , Microambiente Tumoral
8.
Blood ; 140(11): 1291-1304, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35763665

RESUMO

Calreticulin (CALR) mutations are frequent, disease-initiating events in myeloproliferative neoplasms (MPNs). Although the biological mechanism by which CALR mutations cause MPNs has been elucidated, there currently are no clonally selective therapies for CALR-mutant MPNs. To identify unique genetic dependencies in CALR-mutant MPNs, we performed a whole-genome clustered regularly interspaced short palindromic repeats (CRISPR) knockout depletion screen in mutant CALR-transformed hematopoietic cells. We found that genes in the N-glycosylation pathway (among others) were differentially depleted in mutant CALR-transformed cells as compared with control cells. Using a focused pharmacological in vitro screen targeting unique vulnerabilities uncovered in the CRISPR screen, we found that chemical inhibition of N-glycosylation impaired the growth of mutant CALR-transformed cells, through a reduction in MPL cell surface expression. We treated Calr-mutant knockin mice with the N-glycosylation inhibitor 2-deoxy-glucose (2-DG) and found a preferential sensitivity of Calr-mutant cells to 2-DG as compared with wild-type cells and normalization of key MPNs disease features. To validate our findings in primary human cells, we performed megakaryocyte colony-forming unit (CFU-MK) assays. We found that N-glycosylation inhibition significantly reduced CFU-MK formation in patient-derived CALR-mutant bone marrow as compared with bone marrow derived from healthy donors. In aggregate, our findings advance the development of clonally selective treatments for CALR-mutant MPNs.


Assuntos
Calreticulina , Transtornos Mieloproliferativos , Animais , Calreticulina/genética , Calreticulina/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Glucose , Glicosilação , Humanos , Janus Quinase 2/genética , Camundongos , Mutação , Transtornos Mieloproliferativos/genética , Receptores de Trombopoetina/metabolismo
9.
J Nutr ; 154(1): 41-48, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37315794

RESUMO

BACKGROUND: Rapid gastric emptying is associated with obesity and overeating, whereas delayed gastric emptying is associated with anorexia. Acute effects of exercise on gastric emptying have been investigated extensively, but the influence of habitual physical activity on gastric emptying and transit time in other regions of the gastrointestinal tract is poorly understood. OBJECTIVE: The objective was to investigate associations between objectively measured habitual physical activity and gastrointestinal transit times in adults with varying degrees of adiposity. METHODS: 50 adults (58% women) were included in this cross-sectional study. Physical activity was measured by an accelerometer placed on the lower back for 7 d. Gastric emptying time, small bowel transit time, colonic transit time, and whole gut transit time were simultaneously evaluated by a wireless motility capsule, which was ingested together with a standardized mixed meal. Linear regression models were applied to assess the associations of total activity counts and time spent at different intensities-sedentary activity (0-100 counts/min), low light activity (101-759 counts/min), high light activity (760-1951 counts/min); moderate and vigorous activity (≥1952 counts/min)) with gastrointestinal transit times. RESULTS: Median [Q1; Q3] age was 56.5 [46.6-65.5] y, and body mass index (BMI) was 32.1 [28.5-35.1] kg/m2. For every additional hour spent performing high light intensity physical activity, colonic transit time was 25.5 % [95% CI: 3.10, 42.7] more rapid (P = 0.028), and whole gut transit time was 16.2 % [95% CI: 1.84, 28.4] more rapid (P = 0.028) when adjusted for sex, age, and body fat. No other associations were observed. CONCLUSIONS: More time spent on physical activity at high light intensity was associated with more rapid colonic and whole gut transit time, independent of age, sex, and body fat, whereas other intensities of physical activity and gastrointestinal transit times were not associated. TRIAL REGISTRATION: Clinicaltrials.gov IDs (NCT03894670, NCT03854656).


Assuntos
Trânsito Gastrointestinal , Sobrepeso , Adulto , Humanos , Feminino , Masculino , Estudos Transversais , Obesidade , Exercício Físico , Esvaziamento Gástrico
10.
Immunity ; 42(3): 566-79, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25786179

RESUMO

Cigarette smoking is a major risk factor for chronic obstructive pulmonary disease and is presumed to be central to the altered responsiveness to recurrent infection in these patients. We examined the effects of smoke priming underlying the exacerbated response to viral infection in mice. Lack of interleukin-33 (IL-33) signaling conferred complete protection during exacerbation and prevented enhanced inflammation and exaggerated weight loss. Mechanistically, smoke was required to upregulate epithelial-derived IL-33 and simultaneously alter the distribution of the IL-33 receptor ST2. Specifically, smoke decreased ST2 expression on group 2 innate lymphoid cells (ILC2s) while elevating ST2 expression on macrophages and natural killer (NK) cells, thus altering IL-33 responsiveness within the lung. Consequently, upon infection and release, increased local IL-33 significantly amplified type I proinflammatory responses via synergistic modulation of macrophage and NK cell function. Therefore, in COPD, smoke alters the lung microenvironment to facilitate an alternative IL-33-dependent exaggerated proinflammatory response to infection, exacerbating disease.


Assuntos
Imunidade Inata/efeitos dos fármacos , Interleucinas/imunologia , Infecções por Orthomyxoviridae/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Receptores de Interleucina/imunologia , Fumaça/efeitos adversos , Animais , Feminino , Regulação da Expressão Gênica , Humanos , Vírus da Influenza A/imunologia , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33 , Interleucinas/deficiência , Interleucinas/genética , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/patologia , Macrófagos/imunologia , Macrófagos/patologia , Camundongos Transgênicos , Infecções por Orthomyxoviridae/etiologia , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/patologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/patologia , Receptores de Interleucina/deficiência , Receptores de Interleucina/genética , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/imunologia , Mucosa Respiratória/patologia , Transdução de Sinais , Nicotiana/química , Redução de Peso
11.
J Pathol ; 260(5): 514-532, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37608771

RESUMO

Modern histologic imaging platforms coupled with machine learning methods have provided new opportunities to map the spatial distribution of immune cells in the tumor microenvironment. However, there exists no standardized method for describing or analyzing spatial immune cell data, and most reported spatial analyses are rudimentary. In this review, we provide an overview of two approaches for reporting and analyzing spatial data (raster versus vector-based). We then provide a compendium of spatial immune cell metrics that have been reported in the literature, summarizing prognostic associations in the context of a variety of cancers. We conclude by discussing two well-described clinical biomarkers, the breast cancer stromal tumor infiltrating lymphocytes score and the colon cancer Immunoscore, and describe investigative opportunities to improve clinical utility of these spatial biomarkers. © 2023 The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias do Colo , Humanos , Biomarcadores , Benchmarking , Linfócitos do Interstício Tumoral , Análise Espacial , Microambiente Tumoral
12.
J Pathol ; 260(5): 498-513, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37608772

RESUMO

The clinical significance of the tumor-immune interaction in breast cancer is now established, and tumor-infiltrating lymphocytes (TILs) have emerged as predictive and prognostic biomarkers for patients with triple-negative (estrogen receptor, progesterone receptor, and HER2-negative) breast cancer and HER2-positive breast cancer. How computational assessments of TILs might complement manual TIL assessment in trial and daily practices is currently debated. Recent efforts to use machine learning (ML) to automatically evaluate TILs have shown promising results. We review state-of-the-art approaches and identify pitfalls and challenges of automated TIL evaluation by studying the root cause of ML discordances in comparison to manual TIL quantification. We categorize our findings into four main topics: (1) technical slide issues, (2) ML and image analysis aspects, (3) data challenges, and (4) validation issues. The main reason for discordant assessments is the inclusion of false-positive areas or cells identified by performance on certain tissue patterns or design choices in the computational implementation. To aid the adoption of ML for TIL assessment, we provide an in-depth discussion of ML and image analysis, including validation issues that need to be considered before reliable computational reporting of TILs can be incorporated into the trial and routine clinical management of patients with triple-negative breast cancer. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias Mamárias Animais , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Linfócitos do Interstício Tumoral , Biomarcadores , Aprendizado de Máquina
13.
Mol Ther ; 31(4): 1033-1045, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36793213

RESUMO

T cell-based immunotherapy has revolutionized oncological treatment. However, many patients do not respond to treatment, and long-term remissions remain rare, particularly in gastrointestinal cancers like colorectal cancer (CRC). B7-H3 is overexpressed in multiple cancer entities including CRC on both tumor cells and tumor vasculature, the latter facilitating influx of effector cells into the tumor site upon therapeutic targeting. We generated a panel of T cell-recruiting B7-H3xCD3 bispecific antibodies (bsAbs) and show that targeting a membrane-proximal B7-H3 epitope allows for a 100-fold reduction of CD3 affinity. In vitro, our lead compound CC-3 showed superior tumor cell killing, T cell activation, proliferation, and memory formation, whereas undesired cytokine release was reduced. In vivo, CC-3 mediated potent antitumor activity in three independent models using immunocompromised mice adoptively transferred with human effector cells with regard to prevention of lung metastasis and flank tumor growth as well as elimination of large established tumors. Thus, fine-tuning of both target and CD3 affinities as well as binding epitopes allowed for the generation of a B7-H3xCD3 bsAbs with promising therapeutic activity. CC-3 is presently undergoing good manufacturing practice (GMP) production to enable evaluation in a clinical "first-in-human" study in CRC.


Assuntos
Anticorpos Biespecíficos , Neoplasias Gastrointestinais , Humanos , Camundongos , Animais , Imunoglobulina G , Linfócitos T , Neoplasias Gastrointestinais/terapia , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Imunoterapia , Linhagem Celular Tumoral
14.
Nucleic Acids Res ; 50(8): 4315-4328, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-34606604

RESUMO

Many prokaryotes encode CRISPR-Cas systems as immune protection against mobile genetic elements (MGEs), yet a number of MGEs also harbor CRISPR-Cas components. With a few exceptions, CRISPR-Cas loci encoded on MGEs are uncharted and a comprehensive analysis of their distribution, prevalence, diversity, and function is lacking. Here, we systematically investigated CRISPR-Cas loci across the largest curated collection of natural bacterial and archaeal plasmids. CRISPR-Cas loci are widely but heterogeneously distributed across plasmids and, in comparison to host chromosomes, their mean prevalence per Mbp is higher and their distribution is distinct. Furthermore, the spacer content of plasmid CRISPRs exhibits a strong targeting bias towards other plasmids, while chromosomal arrays are enriched with virus-targeting spacers. These contrasting targeting preferences highlight the genetic independence of plasmids and suggest a major role for mediating plasmid-plasmid conflicts. Altogether, CRISPR-Cas are frequent accessory components of many plasmids, which is an overlooked phenomenon that possibly facilitates their dissemination across microbiomes.


Assuntos
Archaea , Sistemas CRISPR-Cas , Archaea/genética , Bactérias/genética , Plasmídeos/genética , Células Procarióticas
15.
J Biomech Eng ; 146(1)2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37943157

RESUMO

Joint compressive forces have been identified as a risk factor for osteoarthritis disease progression. Therefore, unloader braces are a common treatment with the aim of relieving pain, but their effects are not clearly documented in the literature. A knee brace concept was tested with the aim of reducing joint loads and pain in knee osteoarthritis patients by applying an extension moment exclusively during the stance phase. The ideal effects were evaluated during gait based on musculoskeletal modeling of six patients, and experimental tests with a prototype brace were conducted on one patient. The effects were evaluated using electromyography measurements and musculoskeletal models to evaluate the muscle activation and knee compressive forces, respectively. The ideal brace simulations revealed a varying reduction of the first peak knee force between 3.5% and 33.8% across six patients whereas the second peak was unaffected. The prototype reduced the peak vasti muscle activation with 7.9% and musculoskeletal models showed a reduction of the first peak knee compressive force of up to 26.3%. However, the prototype brace increased the knee joint force impulse of up to 17.1% and no immediate pain reduction was observed. The reduction of the first peak knee compressive force, using a prototype on a single patient, indicates a promising effect from an applied knee extension moment for reducing knee joint loads during normal gait. However, further clinical experiments with this brace method are required to evaluate the long-term effects on both pain and disease progression in knee osteoarthritis patients.


Assuntos
Osteoartrite do Joelho , Humanos , Projetos Piloto , Fenômenos Biomecânicos , Articulação do Joelho/fisiologia , Marcha/fisiologia , Dor , Progressão da Doença
16.
Alzheimers Dement ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946683

RESUMO

BACKGROUND: Evidence for the effect of early menopause on cognition among older women is not consistent and is scant among the Indian population. METHODS: We aimed to examine the effect of early menopause (≤45 years) on cognitive performance and brain morphology among older dementia-free females of the TLSA cohort using a multiple linear regression analysis. RESULTS: In a sample of 528 women, 144 (27%) had early menopause. The linear regression analysis showed that women with early menopause performed poorly in cognition and had lesser total gray matter volume [ß = -11973.94, p = 0.033], left middle frontal [ß = -353.14, p = 0.033], and left superior frontal [ß = -460.97, p < 0.026] volume. CONCLUSION: Dementia-free women with early menopause had poorer cognition, lower total gray matter, and frontal lobe. More research is needed to explore the link between earlier menopause and cognitive decline and develop ways to address it. HIGHLIGHTS: Evidence on the effect of early menopause on brain morphology is inconsistent and scant in low and middle-income countries, such as India. In a cohort of dementia-free individuals in urban Bangalore, we observed that participants with early menopause had significantly lower cognitive performance and lower total gray matter and frontal lobe volume. We recommend increasing awareness of this fact among the medical community and the general public. There is an urgent need to explore the underlying biological mechanism and to discover effective interventions to mitigate the effect.

17.
Alzheimers Dement ; 20(4): 2943-2951, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460118

RESUMO

INTRODUCTION: Hypertension and diabetes are modifiable risk factors for dementia. We aimed to assess rural-urban disparities in the diagnosis and treatment of these conditions among aging Indians. METHODS: Participants (n = 6316) were from two parallel, prospective aging cohorts in rural and urban India. Using self-report and clinical/biochemical assessments, we subdivided participants with diabetes and hypertension into undiagnosed and untreated groups. Logistic regression and Fairlie decomposition analysis were the statistical methods utilized. RESULTS: There was a significant rural-urban disparity in undiagnosed hypertension (25.14%), untreated hypertension (11.75%), undiagnosed diabetes (16.94%), and untreated diabetes (11.62%). Further, sociodemographic and lifestyle factors, such as age and tobacco use were the common contributors to the disparities in both undiagnosed hypertension and undiagnosed diabetes, whereas education and body mass index (BMI) were significant contributors to the disparity in untreated hypertension. DISCUSSION: Rural Indians face significant healthcare disadvantages as compared to their urban counterparts, which prompts the urgent need for strategies for equitable healthcare.


Assuntos
Diabetes Mellitus , Hipertensão , Humanos , Anti-Hipertensivos , Estudos Prospectivos , População Urbana , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Envelhecimento , População Rural , Prevalência
18.
Int J Mol Sci ; 25(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38612935

RESUMO

Ligands of the natural killer group 2D (NKG2DL) family are expressed on malignant cells and are usually absent from healthy tissues. Recognition of NKG2DLs such as MICA/B and ULBP1-3 by the activating immunoreceptor NKG2D, expressed by NK and cytotoxic T cells, stimulates anti-tumor immunity in breast cancer. Upregulation of membrane-bound NKG2DLs in breast cancer has been demonstrated by immunohistochemistry. Tumor cells release NKG2DLs via proteolytic cleavage as soluble (s)NKG2DLs, which allows for effective immune escape and is associated with poor prognosis. In this study, we collected serum from 140 breast cancer (BC) and 20 ductal carcinoma in situ (DCIS) patients at the time of initial diagnosis and 20 healthy volunteers (HVs). Serum levels of sNKG2DLs were quantified through the use of ELISA and correlated with clinical data. The analyzed sNKG2DLs were low to absent in HVs and significantly higher in BC patients. For some of the ligands analyzed, higher sNKG2DLs serum levels were associated with the classification of malignant tumor (TNM) stage and grading. Low sMICA serum levels were associated with significantly longer progression-free (PFS) and overall survival (OS). In conclusion, we provide the first insights into sNKG2DLs in BC patients and suggest their potential role in tumor immune escape in breast cancer. Furthermore, our observations suggest that serum sMICA levels may serve as a prognostic parameter in the patients analyzed in this study.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Humanos , Feminino , Pesquisadores , Ensaio de Imunoadsorção Enzimática , Nível de Saúde
19.
Circulation ; 145(5): 321-329, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34779221

RESUMO

BACKGROUND: The PRAETORIAN trial (A Prospective, Randomized Comparison of Subcutaneous and Transvenous Implantable Cardioverter Defibrillator Therapy) showed noninferiority of subcutaneous implantable cardioverter defibrillator (S-ICD) compared with transvenous implantable cardioverter defibrillator (TV-ICD) with regard to inappropriate shocks and complications. In contrast to TV-ICD, S-ICD cannot provide antitachycardia pacing for monomorphic ventricular tachycardia. This prespecified secondary analysis evaluates appropriate therapy and whether antitachycardia pacing reduces the number of appropriate shocks. METHODS: The PRAETORIAN trial was an international, investigator-initiated randomized trial that included patients with an indication for implantable cardioverter defibrillator (ICD) therapy. Patients with previous ventricular tachycardia <170 bpm or refractory recurrent monomorphic ventricular tachycardia were excluded. In 39 centers, 849 patients were randomized to receive an S-ICD (n=426) or TV-ICD (n=423) and were followed for a median of 49.1 months. ICD programming was mandated by protocol. Appropriate ICD therapy was defined as therapy for ventricular arrhythmias. Arrhythmias were classified as discrete episodes and storm episodes (≥3 episodes within 24 hours). Analyses were performed in the modified intention-to-treat population. RESULTS: In the S-ICD group, 86 of 426 patients received appropriate therapy, versus 78 of 423 patients in the TV-ICD group, during a median follow-up of 52 months (48-month Kaplan-Meier estimates 19.4% and 17.5%; P=0.45). In the S-ICD group, 83 patients received at least 1 shock, versus 57 patients in the TV-ICD group (48-month Kaplan-Meier estimates 19.2% and 11.5%; P=0.02). Patients in the S-ICD group had a total of 254 shocks, compared with 228 shocks in the TV-ICD group (P=0.68). First shock efficacy was 93.8% in the S-ICD group and 91.6% in the TV-ICD group (P=0.40). The first antitachycardia pacing attempt successfully terminated 46% of all monomorphic ventricular tachycardias, but accelerated the arrhythmia in 9.4%. Ten patients with S-ICD experienced 13 electrical storms, versus 18 patients with TV-ICD with 19 electrical storms. Patients with appropriate therapy had an almost 2-fold increased relative risk of electrical storms in the TV-ICD group compared with the S-ICD group (P=0.05). CONCLUSIONS: In this trial, no difference was observed in shock efficacy of S-ICD compared with TV-ICD. Although patients in the S-ICD group were more likely to receive an ICD shock, the total number of appropriate shocks was not different between the 2 groups. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01296022.


Assuntos
Arritmias Cardíacas/terapia , Desfibriladores Implantáveis/normas , Idoso , Arritmias Cardíacas/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
20.
Am J Epidemiol ; 192(6): 995-1005, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-36804665

RESUMO

Data sharing is essential for reproducibility of epidemiologic research, replication of findings, pooled analyses in consortia efforts, and maximizing study value to address multiple research questions. However, barriers related to confidentiality, costs, and incentives often limit the extent and speed of data sharing. Epidemiological practices that follow Findable, Accessible, Interoperable, Reusable (FAIR) principles can address these barriers by making data resources findable with the necessary metadata, accessible to authorized users, and interoperable with other data, to optimize the reuse of resources with appropriate credit to its creators. We provide an overview of these principles and describe approaches for implementation in epidemiology. Increasing degrees of FAIRness can be achieved by moving data and code from on-site locations to remote, accessible ("Cloud") data servers, using machine-readable and nonproprietary files, and developing open-source code. Adoption of these practices will improve daily work and collaborative analyses and facilitate compliance with data sharing policies from funders and scientific journals. Achieving a high degree of FAIRness will require funding, training, organizational support, recognition, and incentives for sharing research resources, both data and code. However, these costs are outweighed by the benefits of making research more reproducible, impactful, and equitable by facilitating the reuse of precious research resources by the scientific community.


Assuntos
Confidencialidade , Disseminação de Informação , Humanos , Reprodutibilidade dos Testes , Software , Estudos Epidemiológicos
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