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1.
Proc Natl Acad Sci U S A ; 119(27): e2118529119, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35767640

RESUMO

During normal T cell development in mouse and human, a low-frequency population of immature CD4-CD8- double-negative (DN) thymocytes expresses early, mature αß T cell antigen receptor (TCR). We report that these early αß TCR+ DN (EADN) cells are DN3b-DN4 stage and require CD3δ but not major histocompatibility complex (MHC) for their generation/detection. When MHC - is present, however, EADN cells can respond to it, displaying a degree of coreceptor-independent MHC reactivity not typical of mature, conventional αß T cells. We found these data to be connected with observations that EADN cells were susceptible to T cell acute lymphoblastic leukemia (T-ALL) transformation in both humans and mice. Using the OT-1 TCR transgenic system to model EADN-stage αß TCR expression, we found that EADN leukemogenesis required MHC to induce development of T-ALL bearing NOTCH1 mutations. This leukemia-driving MHC requirement could be lost, however, upon passaging the tumors in vivo, even when matching MHC was continuously present in recipient animals and on the tumor cells themselves. These data demonstrate that MHC:TCR signaling can be required to initiate a cancer phenotype from an understudied developmental state that appears to be represented in the mouse and human disease spectrum.


Assuntos
Linfócitos T CD8-Positivos , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Receptor Notch1 , Receptores de Antígenos de Linfócitos T alfa-beta , Animais , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Antígenos de Histocompatibilidade/metabolismo , Humanos , Complexo Principal de Histocompatibilidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Receptor Notch1/genética , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Timo/metabolismo
2.
J Clin Microbiol ; 59(5)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33653700

RESUMO

The long-lasting global COVID-19 pandemic demands timely genomic investigation of SARS-CoV-2 viruses. Here, we report a simple and efficient workflow for whole-genome sequencing utilizing one-step reverse transcription-PCR (RT-PCR) amplification on a microfluidic platform, followed by MiSeq amplicon sequencing. The method uses Fluidigm integrated fluidic circuit (IFC) and instruments to amplify 48 samples with 39 pairs of primers, including 35 custom-designed primer pairs and four additional primer pairs from the ARTIC network protocol v3. Application of this method on RNA samples from both viral isolates and clinical specimens demonstrates robustness and efficiency in obtaining the full genome sequence of SARS-CoV-2.


Assuntos
Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Microfluídica , SARS-CoV-2/genética , Sequenciamento Completo do Genoma , COVID-19/virologia , Primers do DNA , Humanos , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
J Med Virol ; 93(7): 4570-4575, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33830520

RESUMO

Inpatient coronavirus disease 2019 (COVID-19) cases present enormous costs to patients and health systems in the United States. Many hospitalized patients may continue testing COVID-19 positive even after the resolution of symptoms. Thus, a pressing concern for clinicians is the safety of discharging these asymptomatic patients if they have any remaining infectivity. This case report explores the viral viability in a patient with persistent COVID-19 over the course of a 2-month hospitalization. Positive nasopharyngeal swab samples were collected and isolated in the laboratory and analyzed by quantitative reverse-transcription polymerase chain reactions (qRT-PCR), and serology was tested for neutralizing antibodies throughout the hospitalization period. The patient experienced waning symptoms by hospital day 40 and had no viable virus growth by hospital day 41, suggesting no risk of infectivity, despite positive RT-PCR results which prolonged his hospital stay. Notably, this case showed infectivity for at least 24 days after disease onset, which is longer than the discontinuation of transmission-based precautions recommended by the Center for Disease Control and Prevention. Thus, our findings suggest that the timeline for discontinuing transmission-based precautions may need to be extended for patients with severe and prolonged COVID-19 disease. Additional large-scale studies are needed to draw definitive conclusions on the appropriate clinical management for these patients. ​.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , Eliminação de Partículas Virais/fisiologia , Idoso , Infecções Assintomáticas , Humanos , Masculino , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética , SARS-CoV-2/imunologia
4.
Pediatr Hematol Oncol ; 36(4): 236-243, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31361176

RESUMO

Here we report a case of refractory macrocytic anemia with a spliceosomal point mutation involving the ZRSR2 gene in a child with Down syndrome (DS). Such mutations have been shown to cause refractory macrocytic anemia and myelodysplastic syndrome (MDS) in elderly individuals. We report the hematological indices of a child with DS and a ZRSR2 spliceosomal mutation. DS is known to produce macrocytic anemia but does not lead to transfusion dependence. In this case, the ZRSR2 mutation was the likely implicating factor for severe transfusion-dependent anemia in a child with DS. The clinical implication of a ZRSR2 mutation in a child with DS has not been previously described and warrants close surveillance to detect potential insidious transformation to MDS.


Assuntos
Anemia Macrocítica/genética , Síndrome de Down/genética , Mutação Puntual , Ribonucleoproteínas/genética , Anemia Macrocítica/sangue , Anemia Macrocítica/terapia , Criança , Síndrome de Down/sangue , Síndrome de Down/terapia , Humanos , Masculino , Ribonucleoproteínas/metabolismo
5.
Brain Inj ; 32(13-14): 1849-1857, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30346865

RESUMO

OBJECTIVE: Platelet inhibition in traumatic brain injury (TBI) may be due to injury or antiplatelet medication use pre-injury. This study aims to identify factors associated with increased platelet arachidonic acid (AA) and adenosine diphosphate (ADP) inhibition and determine if platelet transfusion reduces platelet dysfunction and affects outcome. METHODS: Prospective thromboelastography (TEG) assays were collected on adult patients with TBI with intracranial injuries detected by computed tomography (CT). Outcomes included in-hospital mortality, and CT lesion expansion. RESULTS: Of 153 patients, ADP inhibition was increased in moderate and severe TBI compared to mild TBI (p = 0.0011). P2Y12 inhibiting medications had increased ADP inhibition (p = 0.0077). Admission ADP inhibition was not associated with in-hospital mortality (p = 0.24) or CT lesion expansion (p = 0.94). Mean reduction of ADP inhibition from platelet transfusion (-15.1%) relative to no transfusion (+ 11.7%) was not statistically different (p = 0.0472). CONCLUSIONS: Mild TBI results in less ADP inhibition compared to moderate and severe TBI, suggesting a dose response relationship between TBI severity and degree of platelet dysfunction. Further, study is warranted to determine efficacy and parameters for platelet transfusion in patients with TBI.


Assuntos
Transtornos Plaquetários/etiologia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/terapia , Transfusão de Plaquetas/métodos , Difosfato de Adenosina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Araquidônico/sangue , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tromboelastografia/métodos , Tomógrafos Computadorizados , Resultado do Tratamento
6.
N Engl J Med ; 371(7): e9, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-25119625

RESUMO

A 39-year-old woman with a history of gestational diabetes was admitted with epigastric pain from acute pancreatitis. She had no history of hyperlipidemia, but multiple blood samples were grossly lipemic, and serum triglyceride levels were markedly increased.


Assuntos
Eritrócitos/patologia , Hipertrigliceridemia/sangue , Adulto , Feminino , Humanos , Hipertrigliceridemia/complicações , Pancreatite/etiologia , Triglicerídeos/sangue
7.
Transpl Infect Dis ; 19(2)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28036138

RESUMO

Ehrlichiosis in lung transplant (LT) recipients is associated with severe outcomes. Ehrlichia ewingii is a less frequent cause of symptomatic ehrlichiosis, characterized by cytoplasmic inclusions (morulae) within circulating neutrophils. We report a case of E. ewingii infection in an LT recipient diagnosed promptly by blood smear exam and confirmed with molecular studies.


Assuntos
Antibacterianos/uso terapêutico , Ehrlichia/isolamento & purificação , Ehrlichiose/diagnóstico , Febre/diagnóstico , Rejeição de Enxerto/tratamento farmacológico , Terapia de Imunossupressão/efeitos adversos , Imunossupressores/efeitos adversos , Transplante de Pulmão/efeitos adversos , Neutrófilos/microbiologia , Idoso , Animais , Citodiagnóstico/métodos , DNA Bacteriano/isolamento & purificação , Transmissão de Doença Infecciosa , Doxiciclina/uso terapêutico , Diagnóstico Precoce , Ehrlichiose/sangue , Ehrlichiose/tratamento farmacológico , Ehrlichiose/microbiologia , Feminino , Febre/sangue , Febre/tratamento farmacológico , Febre/microbiologia , Humanos , Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Ixodidae/microbiologia , Leucopenia/sangue , Ácido Micofenólico/efeitos adversos , Ácido Micofenólico/uso terapêutico , Reação em Cadeia da Polimerase , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Tacrolimo/efeitos adversos , Tacrolimo/uso terapêutico , Toracentese , Trombocitopenia/sangue , Tomografia Computadorizada por Raios X
9.
Skeletal Radiol ; 45(11): 1571-6, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27596753

RESUMO

We report a case of fulminant sarcoidosis in a 28-year-old man presenting with skin nodules, multifocal small and large joint arthralgias, and blurred vision. Characteristic bone, soft tissue, articular, and CNS findings were evident on multimodality imaging. Bony abnormalities included near-complete destruction of a distal phalanx, "lace-like" lucent lesions, erosive arthritis, lytic lesions with and without sclerotic margins, and bone marrow replacement visible only on MRI. The extent of bony disease at time of presentation was unusual. We review the widely varying reported prevalence of imaging findings of bony sarcoidosis in the literature, and discuss reasons for this variability. We found that musculoskeletal findings at US and MRI were less specific than radiographic and CT findings, but were useful in quantifying extent of disease.


Assuntos
Encefalopatias/diagnóstico por imagem , Artropatias/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Sarcoidose/diagnóstico por imagem , Doenças da Medula Espinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Adulto , Diagnóstico Diferencial , Humanos , Masculino
10.
Cytometry B Clin Cytom ; 106(2): 113-116, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38010113

RESUMO

BACKGROUND: Surface median immunofluorescence intensity (MFI) of plasma cells antigens, particularly CD138, by flow cytometry underestimates plasma cell populations when compared with that estimated by morphological assessment on Wright's-stained slides. CD138 MFI using traditional sample preparation methods for flow cytometric analysis is often dim and difficult to interpret due to multiple factors. This becomes critical when diagnosing and accurately classifying plasma cell dyscrasias. METHODS: In this study, we analyzed 280 flow cytometric results collected from 2016 to 2022 for CD38 and CD138 MFI on bone marrow aspirates performed by two different methods of sample processing-traditional method of lyse-wash and the alternative method of lyse-no-wash. RESULTS: Visual examination of histograms showed a clear advantage to CD138 expression intensity with the no-wash method. Although no significant difference was observed in CD38 MFI between the two techniques (p = 0.3), considerable improvement was observed in CD138 MFI with the lyse-no-wash technique of sample processing compared with the conventional method (p = 0.003). CONCLUSIONS: We concluded that the method of lyse-no-wash is superior to traditional methods especially when it comes to handling bone marrow aspirate samples for plasma cell immunophenotyping. This alternate technique increases the sensitivity of flow cytometry to detect plasma cells resulting in bright and crisp signal intensity for surface CD138. This technique may be particularly advantageous when analyzing low tumor burden such as minimal residual disease.


Assuntos
Mieloma Múltiplo , Paraproteinemias , Humanos , Plasmócitos/patologia , Mieloma Múltiplo/patologia , Citometria de Fluxo/métodos , Paraproteinemias/metabolismo , Imunofenotipagem
11.
Artigo em Inglês | MEDLINE | ID: mdl-38568768

RESUMO

In biomedical literature, biological pathways are commonly described through a combination of images and text. These pathways contain valuable information, including genes and their relationships, which provide insight into biological mechanisms and precision medicine. Curating pathway information across the literature enables the integration of this information to build a comprehensive knowledge base. While some studies have extracted pathway information from images and text independently, they often overlook the correspondence between the two modalities. In this paper, we present a pathway figure curation system named pathCLIP for identifying genes and gene relations from pathway figures. Our key innovation is the use of an image-text contrastive learning model to learn coordinated embeddings of image snippets and text descriptions of genes and gene relations, thereby improving curation. Our validation results, using pathway figures from PubMed, showed that our multimodal model outperforms models using only a single modality. Additionally, our system effectively curates genes and gene relations from multiple literature sources. Two case studies on extracting pathway information from literature of non-small cell lung cancer and Alzheimer's disease further demonstrate the usefulness of our curated pathway information in enhancing related pathways in the KEGG database.

12.
Sci Transl Med ; 16(752): eadl5931, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896605

RESUMO

Clinical treatment of acute myeloid leukemia (AML) largely relies on intensive chemotherapy. However, the application of chemotherapy is often hindered by cardiotoxicity. Patient sequence data revealed that angiotensin II receptor type 1 (AGTR1) is a shared target between AML and cardiovascular disease (CVD). We found that inhibiting AGTR1 sensitized AML to chemotherapy and protected the heart against chemotherapy-induced cardiotoxicity in a human AML cell-transplanted mouse model. These effects were regulated by the AGTR1-Notch1 axis in AML cells and cardiomyocytes from mice. In mouse cardiomyocytes, AGTR1 was hyperactivated by AML and chemotherapy. AML leukemogenesis increased the expression of the angiotensin-converting enzyme and led to increased production of angiotensin II, the ligand of AGTR1, in an MLL-AF9-driven AML mouse model. In this model, the AGTR1-Notch1 axis regulated a variety of genes involved with cell stemness and chemotherapy resistance. AML cell stemness was reduced after Agtr1a deletion in the mouse AML cell transplant model. Mechanistically, Agtr1a deletion decreased γ-secretase formation, which is required for transmembrane Notch1 cleavage and release of the Notch1 intracellular domain into the nucleus. Using multiomics, we identified AGTR1-Notch1 signaling downstream genes and found decreased binding between these gene sequences with Notch1 and chromatin enhancers, as well as increased binding with silencers. These findings describe an AML/CVD association that may be used to improve AML treatment.


Assuntos
Cardiotoxicidade , Modelos Animais de Doenças , Leucemia Mieloide Aguda , Receptor Tipo 1 de Angiotensina , Receptor Notch1 , Animais , Humanos , Camundongos , Secretases da Proteína Precursora do Amiloide/metabolismo , Cardiotoxicidade/metabolismo , Cardiotoxicidade/patologia , Linhagem Celular Tumoral , Coração/efeitos dos fármacos , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Receptor Notch1/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
J Cancer Res Clin Oncol ; 149(7): 3691-3700, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35974175

RESUMO

PURPOSE: This study assessed the impact of adherence to guidelines-recommended diagnostic testing on treatment selection and overall survival (OS) in patients with diffuse large B-cell lymphoma (DLBCL) initiated on rituximab-based first line of treatment (1-LOT). METHODS: This retrospective cohort study used a nationwide electronic health record-derived de-identified database, including diagnostic testing information on immunohistochemistry (IHC), fluorescence in situ hybridization (FISH) and karyotype analysis that were abstracted from pathology reports or clinical visit notes, where available. The study included patients above 18 years old who were diagnosed with DLBCL between January 2011 and December 2019 and initiated on rituximab-based 1-LOT. Patients were classified into 'non-adherence,' 'partial-adherence' and 'complete-adherence' groups according to the evidence/documentation of a confirmed known result for IHC and molecular profiling tests (FISH and karyotyping) on a selection of the markers prior to the initiation of 1-LOT. Logistic regression was used to evaluate associations of adherence to diagnostic testing with 1-LOT between R-CHOP and other rituximab-based regimens. Median OS after the start of rituximab-based 1-LOT was calculated using the Kaplan-Meier method. Multivariable-adjusted Cox proportional hazards regression was used to assess the risk of all-cause death after initiation of 1-LOT by the degrees of adherence to guidelines-recommended diagnostic testing. RESULTS: In total, 3730 patients with DLBCL who initiated on rituximab-based 1-LOT were included. No association was found between adherence to guidelines-recommended diagnostic testing and treatment selection of 1-LOT for R-CHOP versus other rituximab-based regimens. Patients with a higher degree of adherence to guidelines-recommended diagnostic testing survived longer (median OS at 5.1, 6.9 and 7.1 years for 'non-adherence,' 'partial-adherence' and 'complete-adherence' groups, respectively [log-rank p < 0.001]) and had a decreased mortality risk (multivariable-adjusted hazard ratio with 95% confidence intervals at 0.83 [0.70-0.99] for 'partial-adherence' and 0.77 [0.64-0.91] for 'complete-adherence' groups, respectively). CONCLUSION: Patients' adherence to guidelines-recommended diagnostic testing were associated with better survival benefit, reinforcing the need for adoption of diagnostic testing guidelines in routine clinical care.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Difuso de Grandes Células B , Humanos , Rituximab/uso terapêutico , Resultado do Tratamento , Estudos Retrospectivos , Hibridização in Situ Fluorescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Estudos de Coortes , Vincristina/uso terapêutico , Ciclofosfamida/uso terapêutico , Prednisona/uso terapêutico , Doxorrubicina/uso terapêutico
14.
bioRxiv ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37961680

RESUMO

In biomedical literature, biological pathways are commonly described through a combination of images and text. These pathways contain valuable information, including genes and their relationships, which provide insight into biological mechanisms and precision medicine. Curating pathway information across the literature enables the integration of this information to build a comprehensive knowledge base. While some studies have extracted pathway information from images and text independently, they often overlook the correspondence between the two modalities. In this paper, we present a pathway figure curation system named pathCLIP for identifying genes and gene relations from pathway figures. Our key innovation is the use of an image-text contrastive learning model to learn coordinated embeddings of image snippets and text descriptions of genes and gene relations, thereby improving curation. Our validation results, using pathway figures from PubMed, showed that our multimodal model outperforms models using only a single modality. Additionally, our system effectively curates genes and gene relations from multiple literature sources. A case study on extracting pathway information from non-small cell lung cancer literature further demonstrates the usefulness of our curated pathway information in enhancing related pathways in the KEGG database.

15.
Med Rev (2021) ; 3(3): 200-204, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37789956

RESUMO

The biomedical literature is a vast and invaluable resource for biomedical research. Integrating knowledge from the literature with biomedical data can help biological studies and the clinical decision-making process. Efforts have been made to gather information from the biomedical literature and create biomedical knowledge bases, such as KEGG and Reactome. However, manual curation remains the primary method to retrieve accurate biomedical entities and relationships. Manual curation becomes increasingly challenging and costly as the volume of biomedical publications quickly grows. Fortunately, recent advancements in Artificial Intelligence (AI) technologies offer the potential to automate the process of curating, updating, and integrating knowledge from the literature. Herein, we highlight the AI capabilities to aid in mining knowledge and building the knowledge base from the biomedical literature.

16.
bioRxiv ; 2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38187653

RESUMO

ChatGPT has demonstrated its potential as a surrogate knowledge graph. Trained on extensive data sources, including open-access publications, peer-reviewed research articles and biomedical websites, ChatGPT extracted information on gene relationships and biological pathways. However, a major challenge is model hallucination, i.e., high false positive rates. To assess and address this challenge, we systematically evaluated ChatGPT's capacity for predicting gene relationships using GPT-3.5-turbo and GPT-4. Benchmarking against the KEGG Pathway Database as the ground truth, we experimented with diverse prompting strategies, targeting gene relationships of activation, inhibition, and phosphorylation. We introduced an innovative iterative prompt refinement technique. By assessing prompt efficacy using metrics like F-1 score, precision, and recall, GPT-4 was re-engaged to suggest improved prompts. A refined prompt, which combines a specialized role with explanatory text, significantly enhances the performance. Going beyond pairwise gene relationships, we also deciphered complex gene interplays, such as gene interaction chains and pathways pertinent to diseases like non-small cell lung cancer. Direct prompts showed limited success, but "least-to-most" prompting exhibited significant potentials for such network constructions. The methods in this study may be used for some other bioinformatics prediction problems.

17.
Cell Rep ; 42(2): 112105, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36807138

RESUMO

Leukemic-stem-cell-specific targeting may improve the survival of patients with acute myeloid leukemia (AML) by avoiding the ablative effects of standard regimens on normal hematopoiesis. Herein, we perform an unbiased screening of compounds targeting cell surface proteins and identify clinically used DPP4 inhibitors as strong suppressors of AML development in both murine AML models and primary human AML cells xenograft model. We find in retrovirus-induced AML mouse models that DPP4-deficient AML cell-transplanted mice exhibit delay and reversal of AML development, whereas deletion of DPP4 has no significant effect on normal hematopoiesis. DPP4 activates and sustains survival of AML stem cells that are critical for AML development in both human and animal models via binding with Src kinase and activation of nuclear factor κB (NF-κB) signaling. Thus, inhibition of DPP4 is a potential therapeutic strategy against AML development through suppression of survival and stemness of AML cells.


Assuntos
Dipeptidil Peptidase 4 , Leucemia Mieloide Aguda , Animais , Humanos , Camundongos , Dipeptidil Peptidase 4/metabolismo , Modelos Animais de Doenças , Leucemia Mieloide Aguda/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo
18.
Npj Viruses ; 12023.
Artigo em Inglês | MEDLINE | ID: mdl-38186942

RESUMO

In the United States, rural populations comprise 60 million individuals and suffered from high COVID-19 disease burdens. Despite this, surveillance efforts are biased toward urban centers. Consequently, how rurally circulating SARS-CoV-2 viruses contribute toward emerging variants remains poorly understood. In this study, we aim to investigate the role of rural communities in the evolution and transmission of SARS-CoV-2 during the early pandemic. We collected 544 urban and 435 rural COVID-19-positive respiratory specimens from an overall vaccine-naïve population in Southwest Missouri between July and December 2020. Genomic analyses revealed 53 SARS-CoV-2 Pango lineages in our study samples, with 14 of these lineages identified only in rural samples. Phylodynamic analyses showed that frequent bi-directional diffusions occurred between rural and urban communities in Southwest Missouri, and that four out of seven Missouri rural-origin lineages spread globally. Further analyses revealed that the nucleocapsid protein (N):R203K/G204R paired substitutions, which were detected disproportionately across multiple Pango lineages, were more associated with urban than rural sequences. Positive selection was detected at N:204 among rural samples but was not evident in urban samples, suggesting that viruses may encounter distinct selection pressures in rural versus urban communities. This study demonstrates that rural communities may be a crucial source of SARS-CoV-2 evolution and transmission, highlighting the need to expand surveillance and resources to rural populations for COVID-19 mitigation.

20.
Cancers (Basel) ; 14(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36497286

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with limited therapeutic options. Although immunotherapy has shown potential in TNBC patients, clinical studies have only demonstrated a modest response. Therefore, the exploration of immunotherapy in combination with chemotherapy is warranted. In this project we identified immune-related gene signatures for TNBC patients that may explain differences in patients' outcomes after anti-PD-L1+chemotherapy treatment. First, we ran the exploratory subgroup discovery algorithm on the TNBC dataset comprised of 422 patients across 24 studies. Secondly, we narrowed down the search to twelve homogenous subgroups based on tumor mutational burden (TMB, low or high), relapse status (disease-free or recurred), tumor cellularity (high, low and moderate), menopausal status (pre- or post) and tumor stage (I, II and III). For each subgroup we identified a union of the top 10% of genotypic patterns. Furthermore, we employed a multinomial regression model to predict significant genotypic patterns that would be linked to partial remission after anti-PD-L1+chemotherapy treatment. Finally, we uncovered distinct immune cell populations (T-cells, B-cells, Myeloid, NK-cells) for TNBC patients with various treatment outcomes. CD4-Tn-LEF1 and CD4-CXCL13 T-cells were linked to partial remission on anti-PD-L1+chemotherapy treatment. Our informatics pipeline may help to select better responders to chemoimmunotherapy, as well as pinpoint the underlying mechanisms of drug resistance in TNBC patients at single-cell resolution.

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