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1.
Microsyst Nanoeng ; 10(1): 126, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39251611

RESUMO

Patient-derived tumor organoids have emerged as promising models for predicting personalized drug responses in cancer therapy, but they typically lack immune components. Preserving the in vivo association between tumor cells and endogenous immune cells is critical for accurate testing of cancer immunotherapies. Mechanical dissection of tumor specimens into tumor fragments, as opposed to enzymatic digestion into single cells, is essential for maintaining these native tumor-immune cell spatial relationships. However, conventional mechanical dissection relying on manual mincing is time-consuming and irreproducible. This study describes two microdissection devices, the µDicer and µGrater, to facilitate the generation of intact tumor fragments from mouse B16 melanoma, a common model of human melanoma. The µDicer- and µGrater-cut tumor fragments were used to generate air‒liquid interface (ALI) organoids that copreserve tumor cells with infiltrating immune subsets without artificial reconstitution. The µDicer, consisting of a hexagonal array of silicon microblades, was employed to investigate the effect of organoid size. The viability of ALI organoid immune cells appeared insensitive to organoid sizes exceeding ~400 µm but diminished in organoids ~200 µm in size. The µGrater, consisting of an array of submillimeter holes in stainless steel, was employed to accelerate dissection. For the samples studied, the µGrater was 4.5 times faster than manual mincing. Compared with those generated by manual mincing, ALI organoids generated by the µGrater demonstrated similar viability, immune cell composition, and responses to anti-PD-1 immunotherapy. With further optimization, the µGrater holds potential for integration into clinical workflows to support the advancement of personalized cancer immunotherapy.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39214187

RESUMO

OBJECTIVES: Significant heterogeneity has been reported in cohort studies evaluating the impact of early oral antiviral treatment on preventing postacute sequelae after COVID-19. We evaluated the impact of early nirmatrelvir/ritonavir on risk of postacute cardiovascular, neurological, respiratory, and autoimmune diagnoses, as well as postacute symptoms amongst older Singaporeans. METHODS: National COVID-19 registries and healthcare claims databases were used to construct a retrospective population-based cohort enrolling all Singaporeans aged ≥60 years diagnosed with SARS-CoV-2 infection in primary care during Omicron transmission (18 March 2022-4 August 2023). The cohort was divided into nirmatrelvir/ritonavir-treated and untreated groups. Between-group differences in baseline characteristics were adjusted using overlap weighting. Risks of postacute cardiovascular, neurological, respiratory, and autoimmune diagnoses and postacute symptoms (31-180 days) after SARS-CoV-2 infection were contrasted in treated/untreated groups using competing risks regressions (adjusted for demographics/vaccination status/comorbidities). RESULTS: A total of 188 532 older Singaporeans were included; 5.8% (10 905/188 532) received nirmatrelvir/ritonavir. No significantly decreased risk of postacute sequelae (any sequelae: adjusted hazards ratio [aHR], 1.06; 0.94-1.19; cardiovascular sequelae: aHR, 1.01; 0.83-1.24; neurological sequelae: aHR, 1.09; 0.95-1.27; respiratory sequelae: aHR, 1.14; 0.84-1.55; autoimmune sequelae: aHR, 0.76; 0.53-1.09; or any postacute symptom: aHR, 0.97; 0.80-1.18) was observed up to 180 days post-infection in nirmatrelvir/ritonavir-treated individuals vs. untreated cases. Across all vaccination and age subgroups, no significantly decreased risk of any postacute diagnosis/symptom or any cardiovascular, neurological, respiratory, and autoimmune complications up to 180 days post-infection was observed. DISCUSSION: Early outpatient receipt of nirmatrelvir/ritonavir did not significantly reduce risk of postacute cardiovascular, neurological, respiratory, and autoimmune sequelae or the risk of postacute symptoms in a boosted cohort of older Singaporeans.

3.
Appl Environ Microbiol ; 90(9): e0060224, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39177329

RESUMO

The acetogen Acetobacterium woodii couples caffeate reduction with ferredoxin reduction and NADH oxidation via electron bifurcation, providing additional reduced ferredoxin for energy conservation and cell synthesis. Caffeate is first activated by an acyl-CoA synthetase (CarB), which ligates CoA to caffeate at the expense of ATP. After caffeoyl-CoA is reduced to hydrocaffeoyl-CoA, the CoA moiety in hydrocaffeoyl-CoA could be recycled for caffeoyl-CoA synthesis by an ATP-independent CoA transferase (CarA) to save energy. However, given that CarA and CarB are co-expressed, it was not well understood how ATP could be saved when both two competitive pathways of caffeate activation are present. Here, we reported a dual feedback inhibition of the CarB-mediated caffeate activation by the intermediate hydrocaffeoyl-CoA and the end-product hydrocaffeate. As the product of CarA, hydrocaffeate inhibited CarB-mediated caffeate activation by serving as another substrate of CarB with hydrocaffeoyl-CoA produced. It effectively competed with caffeate even at a concentration much lower than caffeate. Hydrocaffeoyl-CoA formed in this process can also inhibit CarB-mediated caffeate activation. Thus, the dual feedback inhibition of CarB, together with the faster kinetics of CarA, makes the ATP-independent CarA-mediated CoA loop the major route for caffeoyl-CoA synthesis, further saving ATP in the caffeate-dependent electron-bifurcating pathway. A genetic architecture similar to carABC has been found in other anaerobic bacteria, suggesting that the feedback inhibition of acyl-CoA ligases could be a widely employed strategy for ATP conservation in those pathways requiring substrate activation by CoA. IMPORTANCE: This study reports a dual feedback inhibition of caffeoyl-CoA synthetase by two downstream products, hydrocaffeate and hydrocaffeoyl-CoA. It elucidates how such dual feedback inhibition suppresses ATP-dependent caffeoyl-CoA synthesis, hence making the ATP-independent route the main pathway of caffeate activation. This newly discovered mechanism contributes to our current understanding of ATP conservation during the caffeate-dependent electron-bifurcating pathway in the ecologically important acetogen Acetobacterium woodii. Bioinformatic mining of microbial genomes revealed contiguous genes homologous to carABC within the genomes of other anaerobes from various environments, suggesting this mechanism may be widely used in other CoA-dependent electron-bifurcating pathways.


Assuntos
Acetobacterium , Trifosfato de Adenosina , Ácidos Cafeicos , Ácidos Cafeicos/metabolismo , Trifosfato de Adenosina/metabolismo , Acetobacterium/genética , Acetobacterium/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Coenzima A Ligases/metabolismo , Coenzima A Ligases/genética , Retroalimentação Fisiológica , Oxirredução , Transporte de Elétrons
4.
JAMA Netw Open ; 7(8): e2430983, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39212988

RESUMO

Importance: Studies have reported increased risk of autoimmune sequelae after SARS-CoV-2 infection. However, risk may potentially be attenuated by milder Omicron (B.1.1.529) variant infection and availability of booster vaccination. Objective: To estimate the 300-day risk of new-incident autoimmune sequelae after SARS-CoV-2 Delta or Omicron BA.1 or BA.2 variant infection in adults who received COVID-19 vaccines and boosters, compared with a contemporary control group without infection. Design, Setting, and Participants: This cohort study in Singapore enrolled adults from September 1, 2021, to March 7, 2022, and followed up for 300 days. Participants were adults aged 18 years or older with SARS-CoV-2 infection during the predominance of the Delta and Omicron BA.1 or BA.2 variants and were still alive at 30 days after COVID-19 diagnosis. Exposure: The national SARS-CoV-2 testing registry was used to construct cohorts of adults with SARS-CoV-2 Delta or Omicron BA.1 or BA.2 variant infection (hereafter, cases) and a contemporaneous group with negative polymerase chain reaction or rapid antigen test results (hereafter, controls). Main Outcomes and Measures: New-incident autoimmune diagnoses after SARS-CoV-2 infection. This information was recorded in the MediClaims national health care claims database and identified 31 to 300 days after index date of infection. Risks and excess burdens were estimated using Cox proportional hazards regression model with overlap weights applied. Results: In total, 1 766 036 adults (915 096 females [51.9%]; mean [SD] age, 49 [18] years) were included in the study population, with 480 082 (27.2%) categorized as cases and 1 285 954 (72.8%) as controls. Of these adults, 73.1% had Chinese, 13.7% Malay, and 9.9% Indian ethnicity. There were 104 179 cases and 666 575 controls included during the Delta variant-predominance transmission, while 375 903 cases and 619 379 controls were included during the Omicron variant-predominance transmission. During the Delta variant period, 81.1% of cases had completed primary vaccination; during the Omicron variant period, 74.6% of cases received boosters. No significantly elevated risk of 12 prespecified autoimmune sequelae was recorded across the Omicron and Delta variant cohorts. Elevated risks of inflammatory bowel disease (adjusted hazard ratio [AHR], 2.23; 95% CI, 1.45-3.46; P < .001) and bullous skin disorders (AHR, 4.88; 95% CI, 2.47-9.66; P < .001) were observed only in the subset of COVID-19 cases requiring hospitalization during the predominance of the Omicron variant. While elevated risk of vasculitis (AHR, 5.74; 95% CI, 1.48-22.23; P = .01) was observed in vaccine-breakthrough Omicron variant infections, no increased risk of vasculitis was observed in the corresponding subgroup who received boosters. Conclusions and Relevance: This cohort study observed no significantly elevated long-term risk of autoimmune sequelae after SARS-CoV-2 Delta and Omicron BA.1 or BA.2 variant infection, except for a modestly increased risk of inflammatory bowel disease and bullous skin disorders in the hospitalized subgroup during the predominance of the Omicron variant. Booster vaccination appeared to mitigate the risk of long-term autoimmune sequelae.


Assuntos
Doenças Autoimunes , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/prevenção & controle , Feminino , Masculino , SARS-CoV-2/imunologia , Pessoa de Meia-Idade , Adulto , Singapura/epidemiologia , Vacinas contra COVID-19/imunologia , Doenças Autoimunes/epidemiologia , Doenças Autoimunes/imunologia , Estudos de Coortes , Idoso
5.
Cancer Discov ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109936

RESUMO

Oncogene amplification on extrachromosomal DNA (ecDNA) is a pervasive driver event in cancer, yet our understanding of how ecDNA forms is limited. Here, we couple a CRISPR-based method for ecDNA induction with extensive characterization of newly formed ecDNA to examine their biogenesis. We find that DNA circularization is efficient, irrespective of 3D genome context, with formation of 800kb, 1 Mb, and 1.8 Mb ecDNAs reaching or exceeding 15%. We show non-homologous end joining and microhomology-mediated end joining both contribute to ecDNA formation, while inhibition of DNA-PKcs and ATM have opposing impacts on ecDNA formation. EcDNA and the corresponding chromosomal excision scar can form at significantly different rates and respond differently to DNA-PKcs and ATM inhibition. Taken together, our results support a model of ecDNA formation in which double strand break ends dissociate from their legitimate ligation partners prior to joining of illegitimate ends to form the ecDNA and excision scar.

6.
J Foot Ankle Surg ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39117130

RESUMO

The quality of national society conferences is often assessed indirectly by analyzing the journal publication rate of the abstracts presented. The conversion rate of abstracts presented at the annual American College of Foot and Ankle Surgeons conference is currently the highest reported (76.9%) for any foot and ankle society to date. The purpose of the present retrospective study was to re-assess the journal publication rate for abstracts (oral manuscript, poster) accepted for presentation at the annual meeting, this time from 2015 to 2019. All accepted abstracts from this period were compiled in a database. PubMed, Google Scholar, and Scopus searches were performed using abstract titles, and author names. The journal publication rate was 80.7% (92/114) for oral manuscripts, and 23.1% (287/1240) for poster abstracts. The mean time to publication was 18.7 months (0 to 75), and 19.1 months (0 to 88) for oral manuscript and posters, respectively. The most common journal for abstract publication was The Journal of Foot and Ankle Surgery. The American College of Foot and Ankle Surgeons oral manuscript publication rate from 2015 to 2019 (80.7%) exceeded the previous reported rate from 2010 to 2014 (76.9%), and is now the highest reported for any national foot and ankle society to date. Attendees of the oral presentations, and readers of the Journal of Foot and Ankle Surgery may remain confident in the quality, and clinical significance of the research presented.

7.
Nat Mater ; 23(8): 1138-1149, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38965405

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is characterized by its fibrotic and stiff extracellular matrix. However, how the altered cell/extracellular-matrix signalling contributes to the PDAC tumour phenotype has been difficult to dissect. Here we design and engineer matrices that recapitulate the key hallmarks of the PDAC tumour extracellular matrix to address this knowledge gap. We show that patient-derived PDAC organoids from three patients develop resistance to several clinically relevant chemotherapies when cultured within high-stiffness matrices mechanically matched to in vivo tumours. Using genetic barcoding, we find that while matrix-specific clonal selection occurs, cellular heterogeneity is not the main driver of chemoresistance. Instead, matrix-induced chemoresistance occurs within a stiff environment due to the increased expression of drug efflux transporters mediated by CD44 receptor interactions with hyaluronan. Moreover, PDAC chemoresistance is reversible following transfer from high- to low-stiffness matrices, suggesting that targeting the fibrotic extracellular matrix may sensitize chemoresistant tumours. Overall, our findings support the potential of engineered matrices and patient-derived organoids for elucidating extracellular matrix contributions to human disease pathophysiology.


Assuntos
Carcinoma Ductal Pancreático , Resistencia a Medicamentos Antineoplásicos , Matriz Extracelular , Organoides , Neoplasias Pancreáticas , Humanos , Organoides/metabolismo , Organoides/patologia , Organoides/efeitos dos fármacos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Matriz Extracelular/metabolismo , Ácido Hialurônico/metabolismo , Ácido Hialurônico/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
8.
Nature ; 632(8024): 401-410, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39048815

RESUMO

In vitro models of autoimmunity are constrained by an inability to culture affected epithelium alongside the complex tissue-resident immune microenvironment. Coeliac disease (CeD) is an autoimmune disease in which dietary gluten-derived peptides bind to the major histocompatibility complex (MHC) class II human leukocyte antigen molecules (HLA)-DQ2 or HLA-DQ8 to initiate immune-mediated duodenal mucosal injury1-4. Here, we generated air-liquid interface (ALI) duodenal organoids from intact fragments of endoscopic biopsies that preserve epithelium alongside native mesenchyme and tissue-resident immune cells as a unit without requiring reconstitution. The immune diversity of ALI organoids spanned T cells, B and plasma cells, natural killer (NK) cells and myeloid cells, with extensive T-cell and B-cell receptor repertoires. HLA-DQ2.5-restricted gluten peptides selectively instigated epithelial destruction in HLA-DQ2.5-expressing organoids derived from CeD patients, and this was antagonized by blocking MHC-II or NKG2C/D. Gluten epitopes stimulated a CeD organoid immune network response in lymphoid and myeloid subsets alongside anti-transglutaminase 2 (TG2) autoantibody production. Functional studies in CeD organoids revealed that interleukin-7 (IL-7) is a gluten-inducible pathogenic modulator that regulates CD8+ T-cell NKG2C/D expression and is necessary and sufficient for epithelial destruction. Furthermore, endogenous IL-7 was markedly upregulated in patient biopsies from active CeD compared with remission disease from gluten-free diets, predominantly in lamina propria mesenchyme. By preserving the epithelium alongside diverse immune populations, this human in vitro CeD model recapitulates gluten-dependent pathology, enables mechanistic investigation and establishes a proof of principle for the organoid modelling of autoimmunity.


Assuntos
Doença Celíaca , Duodeno , Interleucina-7 , Mucosa Intestinal , Modelos Biológicos , Organoides , Humanos , Autoanticorpos/imunologia , Autoimunidade , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biópsia , Doença Celíaca/imunologia , Doença Celíaca/patologia , Doença Celíaca/metabolismo , Duodeno/imunologia , Duodeno/patologia , Duodeno/metabolismo , Epitopos/imunologia , Glutens/imunologia , Glutens/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/imunologia , Antígenos HLA-DQ/imunologia , Antígenos HLA-DQ/metabolismo , Interleucina-7/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Células Matadoras Naturais/imunologia , Células Mieloides/imunologia , Organoides/imunologia , Organoides/metabolismo , Organoides/patologia , Proteína 2 Glutamina gama-Glutamiltransferase/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo
9.
Nat Rev Cancer ; 24(8): 523-539, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38977835

RESUMO

The development of neoplasia involves a complex and continuous interplay between malignantly transformed cells and the tumour microenvironment (TME). Cancer immunotherapies targeting the immune TME have been increasingly validated in clinical trials but response rates vary substantially between tumour histologies and are often transient, idiosyncratic and confounded by resistance. Faithful experimental models of the patient-specific tumour immune microenvironment, capable of recapitulating tumour biology and immunotherapy effects, would greatly improve patient selection, target identification and definition of resistance mechanisms for immuno-oncology therapeutics. In this Review, we discuss currently available and rapidly evolving 3D tumour organoid models that capture important immune features of the TME. We highlight diverse opportunities for organoid-based investigations of tumour immunity, drug development and precision medicine.


Assuntos
Neoplasias , Organoides , Microambiente Tumoral , Microambiente Tumoral/imunologia , Humanos , Organoides/imunologia , Organoides/patologia , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , Medicina de Precisão , Imunoterapia/métodos , Animais , Modelos Biológicos
10.
J Foot Ankle Surg ; 63(5): 546-556, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38825307

RESUMO

Ankle fracture fixation using intramedullary fibular (IMF) nails has been shown to allow for earlier weightbearing, reduced wound complications, better union rates, and the absence of prominent hardware, compared to plates/screw (PS) constructs. The purpose of present retrospective cohort study was to compare outcomes of patients who underwent ankle fracture fixation using an IMF nail versus PS. Demographic, clinical, and radiographic data were recorded for patients who underwent ankle fracture fixation between May 2020 and May 2022, and who were at least 1 year postoperative. Toe-touch weightbearing was permitted immediately after surgery, protected weightbearing (PWB) at postoperative week 2, and weightbearing as tolerated in a brace at week 6. Radiographs were assessed preoperatively, and at 2, 6, 12, 24, and 48 weeks postoperative. Sixty-one ankle fractures (30 IMF, 31 PS) with a mean follow up of 14.7 and 18 (range, 12 to 23) months were included. Overall, the IMF nail cohort had less pain, faster time to union (11.4 vs 13.2 weeks), and less complications (23% vs 45%), reoperations (10% vs 16%), and surgical failures (9% vs 9.7%), compared to the PS cohort. The differences were not statistically significant. The PS cohort had a higher rate of symptomatic hardware irritation (p =< .001). Tobacco use adversely effected direct osseous healing (p < .001) and increased postoperative complications (p = .050). The present study lends credence to the previously reported advantages of IMF nailing over PS fixation for ankle fractures. Ankle fracture fixation using a fourth generation, IMF nail is a viable alternative to traditional PS fixation.


Assuntos
Fraturas do Tornozelo , Placas Ósseas , Fixação Intramedular de Fraturas , Humanos , Fraturas do Tornozelo/cirurgia , Fraturas do Tornozelo/diagnóstico por imagem , Masculino , Feminino , Estudos Retrospectivos , Fixação Intramedular de Fraturas/instrumentação , Fixação Intramedular de Fraturas/métodos , Pessoa de Meia-Idade , Adulto , Pinos Ortopédicos , Fíbula/lesões , Idoso , Suporte de Carga , Resultado do Tratamento , Consolidação da Fratura , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos
11.
JCI Insight ; 9(14)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869953

RESUMO

Duodenal bicarbonate secretion is critical to epithelial protection, as well as nutrient digestion and absorption, and is impaired in cystic fibrosis (CF). We examined if linaclotide, typically used to treat constipation, may also stimulate duodenal bicarbonate secretion. Bicarbonate secretion was measured in vivo and in vitro using mouse and human duodenum (biopsies and enteroids). Ion transporter localization was identified with confocal microscopy, and de novo analysis of human duodenal single-cell RNA sequencing (scRNA-Seq) data sets was performed. Linaclotide increased bicarbonate secretion in mouse and human duodenum in the absence of cystic fibrosis transmembrane conductance regulator (CFTR) expression (Cftr-knockout mice) or function (CFTRinh-172). Na+/H+ exchanger 3 inhibition contributed to a portion of this response. Linaclotide-stimulated bicarbonate secretion was eliminated by down-regulated in adenoma (DRA, SLC26A3) inhibition during loss of CFTR activity. ScRNA-Seq identified that 70% of villus cells expressed SLC26A3, but not CFTR, mRNA. Loss of CFTR activity and linaclotide increased apical brush border expression of DRA in non-CF and CF differentiated enteroids. These data provide further insights into the action of linaclotide and how DRA may compensate for loss of CFTR in regulating luminal pH. Linaclotide may be a useful therapy for CF individuals with impaired bicarbonate secretion.


Assuntos
Bicarbonatos , Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Duodeno , Camundongos Knockout , Peptídeos , Transportadores de Sulfato , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Animais , Camundongos , Bicarbonatos/metabolismo , Humanos , Transportadores de Sulfato/metabolismo , Transportadores de Sulfato/genética , Peptídeos/farmacologia , Fibrose Cística/metabolismo , Fibrose Cística/genética , Fibrose Cística/tratamento farmacológico , Fibrose Cística/patologia , Duodeno/metabolismo , Duodeno/efeitos dos fármacos , Trocador 3 de Sódio-Hidrogênio/metabolismo , Trocador 3 de Sódio-Hidrogênio/genética , Masculino , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Antiporters , Antiportadores de Cloreto-Bicarbonato
12.
Chest ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871281

RESUMO

BACKGROUND: Individuals with chronic lung disease (CLD) are more susceptible to respiratory viral infections; however, significant heterogeneity exists in the literature on CLD and COVID-19 outcomes. Data are lacking on outcomes with newer variants (eg, Omicron) and in vaccinated and boosted populations. RESEARCH QUESTION: What are the outcomes of SARS-CoV-2 infection in individuals with CLD during Delta and Omicron transmission in a highly vaccinated and boosted population-based cohort? STUDY DESIGN AND METHODS: Outcomes of Delta and Omicron SARS-CoV-2 infection in a highly vaccinated and boosted cohort of adult Singaporeans with CLD (including asthma, COPD, bronchiectasis, and pulmonary fibrosis) were contrasted against matched population control participants. Calendar time-scale Cox regressions were used to compare risk of infection, COVID-19-related hospitalizations, and severe COVID-19 disease, adjusting for sociodemographic factors and comorbidities. RESULTS: Overall, 68,782 individual patients with CLD and 534,364 matched population control participants were included. By the end of the Omicron wave, 92.7% of patients with CLD were boosted. Compared with control participants, patients with CLD showed higher risk of SARS-CoV-2 infection, COVID-19-related hospitalization, and severe COVID-19 during both the Delta wave (infection: adjusted hazards ratio [aHR], 1.22 [95% CI, 1.17-1.28]; hospitalization: aHR, 1.76 [95% CI, 1.61-1.92]; severe COVID-19: aHR, 1.75 [95% CI, 1.50-2.05]) and Omicron wave (infection: aHR, 1.15 [95% CI, 1.14-1.17]; hospitalization: aHR, 1.82 [95% CI, 1.74-1.91]; severe COVID-19: aHR, 2.39 [95% CI, 2.18-2.63]). During Omicron, significantly higher risk of infection, hospitalization, and severe COVID-19 was observed among patients with asthma (severe COVID-19: aHR, 1.31 [95% CI, 1.10-1.55]) and COPD (severe COVID-19: aHR, 1.36 [95% CI, 1.12-1.66]) compared with control participants. Severe exacerbation (requiring hospitalization) in the preceding year was associated with higher risk of poorer outcomes (Delta, severe COVID-19: aHR, 9.84 [95% CI, 6.33-15.28]; Omicron, severe COVID-19: aHR, 19.22 [95% CI, 15.35-24.06]). Risk was attenuated in the boosted group, with numerically lower HRs against hospitalization and severe COVID-19 in the four-dose group compared with the three-dose group. INTERPRETATION: Increased risk of COVID-19-related hospitalization and severe COVID-19 was observed among patients with CLD compared with matched population control participants during Delta and Omicron predominance. Boosting attenuated serious COVID-19 outcomes.

13.
J Biol Chem ; 300(8): 107514, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945449

RESUMO

The development of safe and effective broad-spectrum antivirals that target the replication machinery of respiratory viruses is of high priority in pandemic preparedness programs. Here, we studied the mechanism of action of a newly discovered nucleotide analog against diverse RNA-dependent RNA polymerases (RdRps) of prototypic respiratory viruses. GS-646939 is the active 5'-triphosphate metabolite of a 4'-cyano modified C-adenosine analog phosphoramidate prodrug GS-7682. Enzyme kinetics show that the RdRps of human rhinovirus type 16 (HRV-16) and enterovirus 71 incorporate GS-646939 with unprecedented selectivity; GS-646939 is incorporated 20-50-fold more efficiently than its natural ATP counterpart. The RdRp complex of respiratory syncytial virus and human metapneumovirus incorporate GS-646939 and ATP with similar efficiency. In contrast, influenza B RdRp shows a clear preference for ATP and human mitochondrial RNA polymerase does not show significant incorporation of GS-646939. Once incorporated into the nascent RNA strand, GS-646939 acts as a chain terminator although higher NTP concentrations can partially overcome inhibition for some polymerases. Modeling and biochemical data suggest that the 4'-modification inhibits RdRp translocation. Comparative studies with GS-443902, the active triphosphate form of the 1'-cyano modified prodrugs remdesivir and obeldesivir, reveal not only different mechanisms of inhibition, but also differences in the spectrum of inhibition of viral polymerases. In conclusion, 1'-cyano and 4'-cyano modifications of nucleotide analogs provide complementary strategies to target the polymerase of several families of respiratory RNA viruses.


Assuntos
Antivirais , RNA Polimerase Dependente de RNA , Humanos , Antivirais/farmacologia , Antivirais/química , RNA Polimerase Dependente de RNA/antagonistas & inibidores , RNA Polimerase Dependente de RNA/metabolismo , RNA Polimerase Dependente de RNA/química , Vírus de RNA/efeitos dos fármacos , Vírus de RNA/enzimologia , Metapneumovirus/efeitos dos fármacos , Nucleotídeos/química , Nucleotídeos/farmacologia , Nucleotídeos/metabolismo
14.
Clin Microbiol Infect ; 30(10): 1319-1326, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38908748

RESUMO

OBJECTIVES: Evidence suggests that some COVID-19 survivors experience a wide range of post-COVID-19 sequelae; however, the majority of studies were conducted before the emergence of the milder Omicron variant. We examined the post-acute risk of new-incident cardiovascular complications after SARS-CoV-2 infection in a multi-ethnic Asian population, during Omicron predominance. METHODS: This cohort study used national testing and healthcare claims databases in Singapore to build a cohort of individuals with confirmed SARS-CoV-2 infection during Omicron BA.1/2 transmission and a contemporaneous test-negative group. Participants in both groups were followed up for a median of 300 days. We estimated risks of new-incident cardiovascular complications using doubly robust competing-risks survival analysis. Risks were reported using two measures: hazard ratio and excess burden. RESULTS: We included 375 903 test-positive, infected individuals (mean age 48 years) and 619 379 test-negative controls (mean age 47 years). The majority (97.5%, 366 593/375 903) of infected individuals had mild infection not requiring hospitalization. There was no overall increased risk of new-incident cardiovascular complications, (adjusted hazards ratio, aHR = 1.01 [0.97-1.07]) amongst COVID-19 survivors when compared against test-negatives. A modestly increased risk and excess burden of dysrhythmias amongst COVID-19 survivors (aHR = 1.09 [1.01-1.19]) was observed. Risk and burdens of new-incident cardiovascular complications predominantly accrued in hospitalized (aHR = 2.81 [2.26-3.50]) and severe COVID-19 cases (aHR = 5.52 [3.76-8.10]). DISCUSSION: No significantly increased overall risk of any cardiovascular complication was observed in the 300 days following COVID-19 infection during the Omicron-dominant period when compared against test-negatives, with the exception of a small increased occurrence of dysrhythmias.


Assuntos
COVID-19 , Doenças Cardiovasculares , Transtornos Cerebrovasculares , SARS-CoV-2 , Trombose , Humanos , COVID-19/complicações , COVID-19/epidemiologia , Pessoa de Meia-Idade , Masculino , Feminino , Estudos Retrospectivos , Singapura/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Adulto , Trombose/etiologia , Trombose/epidemiologia , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/epidemiologia , Idoso , Fatores de Risco
15.
J Cardiothorac Vasc Anesth ; 38(10): 2254-2260, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38918090

RESUMO

OBJECTIVES: Hypertrophic obstructive cardiomyopathy (HOCM) may be treated by septal myectomy. Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication, but little is known about its incidence after septal myectomy. The objectives of this work were to evaluate the prevalence of CSA-AKI after septal myectomy and identify potential perioperative and phenotype-related factors contributing to CSA-AKI. DESIGN: This was a retrospective database analysis with new data analysis. SETTING: The study occurred in a single university academic expertise center for septal myectomy HOCM patients. PARTICIPANTS: Data from 238 HOCM patients with septal myectomy operated on between 2005 and 2022 were collected. INTERVENTIONS: CSA-AKI was stratified according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines using measurement of creatinine and urine production. Important HOCM phenotype-related and perioperative factors were analyzed for their possible associations with CSA-AKI. MEASUREMENTS AND MAIN RESULTS: CSA-AKI occurred in 45% of patients; of these, 55% were classified as KDIGO stage I and the remaining 45% as stage II, with no chronic kidney damage observed. Moreover, there were no phenotypical or perioperative characteristics that were more prevalent in the CSA-AKI cohort. However, the use of beta-blockers and coronary artery disease were more prevalent in the CSA-AKI cohort. CONCLUSIONS: CSA-AKI is a common complication after septal myectomy but was transient, and kidney function recovered in all patients.


Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Cardiomiopatia Hipertrófica , Septos Cardíacos , Complicações Pós-Operatórias , Humanos , Cardiomiopatia Hipertrófica/cirurgia , Cardiomiopatia Hipertrófica/epidemiologia , Cardiomiopatia Hipertrófica/complicações , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Masculino , Feminino , Estudos Retrospectivos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/tendências , Pessoa de Meia-Idade , Prevalência , Septos Cardíacos/cirurgia , Septos Cardíacos/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Idoso
16.
Clin Infect Dis ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922669

RESUMO

INTRODUCTION: Data on protection afforded by updated COVID-19 vaccines (bivalent/XBB 1.5 monovalent) against the emergent JN.1 variant remains limited. METHODS: We conducted a retrospective population-based cohort study amongst all boosted Singaporeans aged ≥18 years during a COVID-19 wave predominantly driven by JN.1, from 26th November 2023 to 13th January 2024. Multivariable Cox regression was utilised to assess risk of SARS-CoV-2 infection and COVID-19 associated emergency-department (ED) visits/hospitalizations, stratified by vaccination status/prior infection; with individuals last boosted ≥1 year utilized as the reference category. Vaccination and infection status were classified using national registries. RESULTS: 3,086,562 boosted adult Singaporeans were included in the study population, accounting for 146,863,476 person-days of observation. During the JN.1 outbreak, 28,160 SARS-CoV-2 infections were recorded, with 2,926 hospitalizations and 3,747 ED-visits. Compared with individuals last boosted ≥1 year prior with ancestral monovalent vaccines, receipt of an updated XBB.1.5 booster 8-120 days prior was associated with lower risk of JN.1 infection (adjusted-hazard-ratio, aHR = 0.59[0.52-0.66]), COVID-19 associated ED-visits (aHR = 0.50[0.34-0.73]) and hospitalizations(aHR = 0.58[0.37-0.91]), while receipt of a bivalent booster 121-365 days prior was associated with lower risk of JN.1 infection (aHR = 0.92[0.88-0.95]) and ED-visits (aHR = 0.80[0.70-0.90]). Lower risk of COVID-19 hospitalization during the JN.1 outbreak (aHR = 0.57[0.33-0.97]) was still observed following receipt of an updated XBB.1.5 booster 8-120 days prior, even when analysis was restricted to previously infected individuals. CONCLUSION: Recent receipt of updated boosters conferred protection against SARS-CoV-2 infection and ED-visits/hospitalization during a JN.1 variant wave, in both previously infected and uninfected individuals. Annual booster doses confer protection during COVID-19 endemicity.

17.
Nat Commun ; 15(1): 3741, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702301

RESUMO

Targeted therapy is effective in many tumor types including lung cancer, the leading cause of cancer mortality. Paradigm defining examples are targeted therapies directed against non-small cell lung cancer (NSCLC) subtypes with oncogenic alterations in EGFR, ALK and KRAS. The success of targeted therapy is limited by drug-tolerant persister cells (DTPs) which withstand and adapt to treatment and comprise the residual disease state that is typical during treatment with clinical targeted therapies. Here, we integrate studies in patient-derived and immunocompetent lung cancer models and clinical specimens obtained from patients on targeted therapy to uncover a focal adhesion kinase (FAK)-YAP signaling axis that promotes residual disease during oncogenic EGFR-, ALK-, and KRAS-targeted therapies. FAK-YAP signaling inhibition combined with the primary targeted therapy suppressed residual drug-tolerant cells and enhanced tumor responses. This study unveils a FAK-YAP signaling module that promotes residual disease in lung cancer and mechanism-based therapeutic strategies to improve tumor response.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , Transdução de Sinais , Fatores de Transcrição , Proteínas de Sinalização YAP , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Sinalização YAP/metabolismo , Linhagem Celular Tumoral , Animais , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasia Residual , Camundongos , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Quinase do Linfoma Anaplásico/metabolismo , Quinase do Linfoma Anaplásico/genética , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Mol Ther ; 32(7): 2064-2079, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38715361

RESUMO

We investigated long-term human coagulation factor IX (huFIX) expression of a novel variant when delivered into mice and rhesus macaques and compared transduction efficiencies using two different adeno-associated virus (AAV) capsids. In hemophilic mice injected with KP1-packaged recombinant AAV (rAAV) expressing the hyperactive FIX variant specific activity plasma levels were 10-fold or 2-fold enhanced when compared with wild-type or Padua huFIX injected mice, respectively. In rhesus macaques AAV-LK03 capsid outperformed AAV-KP1 in terms of antigen expression and liver transduction. Two animals from each group showed sustained low-level huFIX expression at 3 months after administration, while one animal from each group lost huFIX mRNA and protein expression over time, despite comparable vector copies. We investigated whether epigenetic differences in the vector episomes could explain this loss of transcription. Cut&Tag analysis revealed lower levels of activating histone marks in the two animals that lost expression. When comparing rAAV genome associated histone modifications in rhesus macaques with those in mice injected with the same vector, the activating histone marks were starkly decreased in macaque-derived episomes. Differential epigenetic marking of AAV genomes may explain different expression profiles in mice and rhesus macaques, as well as the wide dose response variation observed in primates in both preclinical and human clinical trials.


Assuntos
Dependovirus , Epigênese Genética , Fator IX , Vetores Genéticos , Macaca mulatta , Animais , Fator IX/genética , Fator IX/metabolismo , Dependovirus/genética , Camundongos , Humanos , Vetores Genéticos/genética , Vetores Genéticos/administração & dosagem , Hemofilia B/genética , Hemofilia B/terapia , Transdução Genética , Terapia Genética/métodos
19.
Trends Neurosci ; 47(7): 522-537, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38782701

RESUMO

Sensory systems experience a period of intrinsically generated neural activity before maturation is complete and sensory transduction occurs. Here we review evidence describing the mechanisms and functions of this 'spontaneous' activity in the auditory system. Both ex vivo and in vivo studies indicate that this correlated activity is initiated by non-sensory supporting cells within the developing cochlea, which induce depolarization and burst firing of groups of nearby hair cells in the sensory epithelium, activity that is conveyed to auditory neurons that will later process similar sound features. This stereotyped neural burst firing promotes cellular maturation, synaptic refinement, acoustic sensitivity, and establishment of sound-responsive domains in the brain. While sensitive to perturbation, the developing auditory system exhibits remarkable homeostatic mechanisms to preserve periodic burst firing in deaf mice. Preservation of this early spontaneous activity in the context of deafness may enhance the efficacy of later interventions to restore hearing.


Assuntos
Cóclea , Audição , Animais , Cóclea/fisiologia , Humanos , Audição/fisiologia , Vias Auditivas/fisiologia , Percepção Auditiva/fisiologia , Células Ciliadas Auditivas/fisiologia
20.
Nature ; 630(8016): 457-465, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750365

RESUMO

Adoptively transferred T cells and agents designed to block the CD47-SIRPα axis are promising cancer therapeutics that activate distinct arms of the immune system1,2. Here we administered anti-CD47 antibodies in combination with adoptively transferred T cells with the goal of enhancing antitumour efficacy but observed abrogated therapeutic benefit due to rapid macrophage-mediated clearance of T cells expressing chimeric antigen receptors (CARs) or engineered T cell receptors. Anti-CD47-antibody-mediated CAR T cell clearance was potent and rapid enough to serve as an effective safety switch. To overcome this challenge, we engineered the CD47 variant CD47(Q31P) (47E), which engages SIRPα and provides a 'don't eat me' signal that is not blocked by anti-CD47 antibodies. TCR or CAR T cells expressing 47E are resistant to clearance by macrophages after treatment with anti-CD47 antibodies, and mediate substantial, sustained macrophage recruitment to the tumour microenvironment. Although many of the recruited macrophages manifested an M2-like profile3, the combined therapy synergistically enhanced antitumour efficacy. Our study identifies macrophages as major regulators of T cell persistence and illustrates the fundamental challenge of combining T-cell-directed therapeutics with those designed to activate macrophages. It delivers a therapeutic approach that is capable of simultaneously harnessing the antitumour effects of T cells and macrophages, offering enhanced potency against solid tumours.


Assuntos
Antígeno CD47 , Imunoterapia Adotiva , Neoplasias , Linfócitos T , Animais , Feminino , Humanos , Masculino , Camundongos , Antígenos de Diferenciação/imunologia , Antígenos de Diferenciação/metabolismo , Antígeno CD47/genética , Antígeno CD47/imunologia , Antígeno CD47/metabolismo , Linhagem Celular Tumoral , Imunoterapia Adotiva/métodos , Macrófagos/citologia , Macrófagos/imunologia , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/transplante , Microambiente Tumoral/imunologia , Anticorpos/imunologia , Anticorpos/uso terapêutico , Ativação de Macrófagos
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