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1.
J Infect Public Health ; 17(4): 696-703, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38479066

ABSTRACT

BACKGROUND: Food-borne pathogen Listeria monocytogenes is abundantly present in nature and accountable for sporadic and epidemic cases of listeriosis in humans. The objective of this study was to screen common food sources for L. monocytogenes using biochemical and molecular methods to detect and characterise its toxin genes as well as for biofilm formation. METHODS: A total of 92 samples, comprising dairy and street food products, were randomly collected from various sources for this investigation. The collected samples were processed for biochemical and molecular methods to detect L. monocytogenes. Additionally, virulence factors associated genes, antibiogram profiles and biofilm formation related assays were determined. RESULTS: L. monocytogenes presence was confirmed using molecular detection methods targeting prs and lmo1030 genes, along with MALDI-TOF MS. Following 16 S rRNA sequencing, the identified Listeria species were further categorised into two groups. L. monocytogenes was detected in two (2.17%) food samples tested (L-23 and L-74). Multiplex PCR indicated the presence of seven virulence-related genes in L. monocytogenes isolates, i.e., inlA, inlB, prfA, iap, actA, plcB, and hlyA. In addition, 17 antibiotics were tested, whereby two isolates showed resistance to clindamycin and azithromycin, while one isolate (L-74) was also resistant to nalidixic acid, co-trimoxazole, ampicillin, norfloxacin, and cefotaxime. L-23 and L-74 isolates showed biofilm formation, especially at pH 8.6 and 37°C. CONCLUSIONS: Besides the demonstration of the presence of L. monocytogenes in some dairy and street food products, this study underscores the need to increase the standards of hygiene on the one hand and the importance of the surveillance of food-borne pathogens on the other.


Subject(s)
Listeria monocytogenes , Listeriosis , Humans , Listeria monocytogenes/genetics , India , Anti-Bacterial Agents/pharmacology , Virulence Factors/genetics , Food Microbiology
2.
Interface Focus ; 13(6): 20230044, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38106912

ABSTRACT

Persistent atrial fibrillation (AF) is not effectively treated due to a lack of adequate tools for identifying patient-specific AF substrates. Recent studies revealed that in 30-50% of patients, persistent AF is maintained by localized drivers not only in the left atrium (LA) but also in the right atrium (RA). The chamber-specific atrial wall thickness (AWT) features underlying AF remain elusive, though the important role of AWT in AF is widely acknowledged. We aimed to provide direct evidence of the existence of distinguished RA and LA AWT features underlying AF drivers by analysing functionally and structurally mapped human hearts ex vivo. Coronary-perfused intact human atria (n = 7, 47 ± 14 y.o.; two female) were mapped using panoramic near-infrared optical mapping during pacing-induced AF. Then the hearts were imaged at approximately 170 µm3 resolution by 9.4 T gadolinium-enhanced MRI. The heart was segmented, and 3D AWT throughout atrial chambers was estimated and analysed. Optical mapping identified six localized RA re-entrant drivers in four hearts and four LA drivers in three hearts. All RA AF drivers were anchored to the pectinate muscle junctions with the crista terminalis or atrial walls. The four LA AF drivers were in the posterior LA. RA (n = 4) with AF drivers were thicker with greater AWT variation than RA (n = 3) without drivers (5.4 ± 2.6 mm versus 5.0 ± 2.4 mm, T-test p < 0.05; F-test p < 0.05). Furthermore, AWT in RA driver regions was thicker and varied more than in RA non-driver regions (5.1 ± 2.5 mm versus 4.4 ± 2.2 mm, T-test p < 0.05; F-test p < 0.05). On the other hand, LA (n = 3) with drivers was thinner than the LA (n = 4) without drivers. In particular, LA driver regions were thinner than the rest of LA regions (3.4 ± 1.0 mm versus 4.2 ± 1.0 mm, T-test p < 0.05). This study demonstrates chamber-specific AWT features of AF drivers. In RA, driver regions are thicker and have more variable AWT than non-driver regions. By contrast, LA drivers are thinner than non-drivers. Robust evaluation of patient-specific AWT features should be considered for chamber-specific targeted ablation.

3.
PLoS Comput Biol ; 19(12): e1011708, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38109436

ABSTRACT

The sinoatrial node (SAN), the primary pacemaker of the heart, is responsible for the initiation and robust regulation of sinus rhythm. 3D mapping studies of the ex-vivo human heart suggested that the robust regulation of sinus rhythm relies on specialized fibrotically-insulated pacemaker compartments (head, center and tail) with heterogeneous expressions of key ion channels and receptors. They also revealed up to five sinoatrial conduction pathways (SACPs), which electrically connect the SAN with neighboring right atrium (RA). To elucidate the role of these structural-molecular factors in the functional robustness of human SAN, we developed comprehensive biophysical computer models of the SAN based on 3D structural, functional and molecular mapping of ex-vivo human hearts. Our key finding is that the electrical insulation of the SAN except SACPs, the heterogeneous expression of If, INa currents and adenosine A1 receptors (A1R) across SAN pacemaker-conduction compartments are required to experimentally reproduce observed SAN activation patterns and important phenomena such as shifts of the leading pacemaker and preferential SACP. In particular, we found that the insulating border between the SAN and RA, is required for robust SAN function and protection from SAN arrest during adenosine challenge. The heterogeneity in the expression of A1R within the human SAN compartments underlies the direction of pacemaker shift and preferential SACPs in the presence of adenosine. Alterations of INa current and fibrotic remodelling in SACPs can significantly modulate SAN conduction and shift the preferential SACP/exit from SAN. Finally, we show that disease-induced fibrotic remodeling, INa suppression or increased adenosine make the human SAN vulnerable to pacing-induced exit blocks and reentrant arrhythmia. In summary, our computer model recapitulates the structural and functional features of the human SAN and can be a valuable tool for investigating mechanisms of SAN automaticity and conduction as well as SAN arrhythmia mechanisms under different pathophysiological conditions.


Subject(s)
Heart Conduction System , Sinoatrial Node , Humans , Sinoatrial Node/physiology , Arrhythmias, Cardiac , Adenosine , Computer Simulation
4.
Interface Focus ; 13(6): 20230039, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38106916

ABSTRACT

This study aimed to use multi-scale atrial models to investigate pulmonary arterial hypertension (PAH)-induced atrial fibrillation mechanisms. The results of our computer simulations revealed that, at the single-cell level, PAH-induced remodelling led to a prolonged action potential (AP) (ΔAPD: 49.6 ms in the right atria (RA) versus 41.6 ms in the left atria (LA)) and an increased calcium transient (CaT) (ΔCaT: 7.5 × 10-2 µM in the RA versus 0.9 × 10-3 µM in the LA). Moreover, heterogeneous remodelling increased susceptibility to afterdepolarizations, particularly in the RA. At the tissue level, we observed a significant reduction in conduction velocity (CV) (ΔCV: -0.5 m s-1 in the RA versus -0.05 m s-1 in the LA), leading to a shortened wavelength in the RA, but not in the LA. Additionally, afterdepolarizations in the RA contributed to enhanced repolarization dispersion and facilitated unidirectional conduction block. Furthermore, the increased fibrosis in the RA amplified the likelihood of excitation wave breakdown and the occurrence of sustained re-entries. Our results indicated that the RA is characterized by increased susceptibility to afterdepolarizations, slow conduction, reduced wavelength and upregulated fibrosis. These findings shed light on the underlying factors that may promote atrial fibrillation in patients with PAH.

5.
Interface Focus ; 13(6): 20230041, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38106913

ABSTRACT

Fibrosis has been mechanistically linked to arrhythmogenesis in multiple cardiovascular conditions, including atrial fibrillation (AF). Previous studies have demonstrated that fibrosis can create functional barriers to conduction which may promote excitation wavebreak and the generation of re-entry, while also acting to pin re-entrant excitation in stable rotors during AF. However, few studies have investigated the role of fibrosis in the generation of AF triggers in detail. We apply our in-house computational framework to study the impact of fibrosis on the generation of AF triggers and trigger-substrate interactions in two- and three-dimensional atrial tissue models. Our models include a reduced and efficient description of stochastic, spontaneous cellular triggers as well as a simple model of heterogeneous inter-cellular coupling. Our results demonstrate that fibrosis promotes the emergence of focal excitations, primarily through reducing the electrotonic load on individual fibre strands. This enables excitation to robustly initiate within these single strands before spreading to neighbouring strands and inducing a full tissue focal excitation. Enhanced conduction block can allow trigger-substrate interactions that result in the emergence of complex, re-entrant excitation patterns. This study provides new insight into the mechanisms by which fibrosis promotes the triggers and substrate necessary to induce and sustain arrhythmia.

6.
Conserv Biol ; 37(6): e14150, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37461881

ABSTRACT

Programs to protect biodiversity on private land are increasingly being used worldwide. To understand the efficacy of such programs, it is important to determine their impact: the difference between the program's outcome and what would have happened without the program. Typically, these programs are evaluated by estimating the average program-level impact, which readily allows comparisons between programs or regions, but masks important heterogeneity in impact across the individual conservation interventions. We used synthetic control design, statistical matching, and time-series data to estimate the impact of individual protected areas over time and combined individual-level impacts to estimate program-level impact with a meta-analytic approach. We applied the method to private protected areas governed by conservation covenants (legally binding on-title agreements to protect biodiversity) in the Goldfields region of Victoria, Australia using woody vegetation cover as our outcome variable. We compared our results with traditional approaches to estimating program-level impact based on a subset of covenants that were the same age. Our results showed an overall program-level impact of a 0.3-0.8% increase in woody vegetation cover per year. However, there was significant heterogeneity in the temporal pattern of impact for individual covenants, ranging from -4 to +7% change in woody vegetation cover per year. Results of our approach were consistent with results based on traditional approaches to estimating program-level impact. Our study provides a transparent and robust workflow to estimate individual and program-level impacts of private protected areas.


Evaluación del impacto del suelo privado de conservación con diseño de control sintético Resumen Los programas de protección de la biodiversidad en suelo privado se utilizan cada vez más en todo el mundo. Para entender la eficacia de estos programas, es importante determinar la diferencia entre el resultado del programa y lo que habría ocurrido sin él. Normalmente, estos programas se evalúan estimando el impacto medio a nivel de programa, lo que permite fácilmente las comparaciones entre programas o regiones, pero oculta una importante heterogeneidad en el impacto entre las intervenciones individuales de conservación. Utilizamos un diseño de control sintético, un emparejamiento estadístico y datos de series temporales para estimar el impacto de las áreas protegidas individuales a lo largo del tiempo y combinamos los impactos a nivel individual para estimar el impacto a nivel de programa con un enfoque meta-analítico. Aplicamos el método a áreas protegidas privadas regidas por acuerdos de conservación (acuerdos con vínculos jurídicos sobre la titularidad para proteger la biodiversidad) destinados a mejorar la cubierta vegetal leñosa en la región de Goldfields de Victoria, Australia. Comparamos nuestros resultados con los métodos tradicionales de estimación del impacto a nivel de programa basados en un subconjunto de pactos de la misma antigüedad. Nuestros resultados mostraron un impacto global a nivel de programa de un aumento del 0.3-0.8% de la cubierta vegetal leñosa al año. Sin embargo, hubo una heterogeneidad significativa en el patrón temporal del impacto para los pactos individuales, que osciló entre −4 y +7% de cambio en la cubierta vegetal leñosa por año. Los resultados de nuestra estrategia fueron consecuentes con los resultados basados en las estrategias tradicionales usadas para estimar el impacto a nivel de programa. Nuestro estudio proporciona un flujo de trabajo transparente y sólido para estimar el impacto individual a nivel de programa de las áreas protegidas privadas.


Subject(s)
Biodiversity , Conservation of Natural Resources , Conservation of Natural Resources/methods , Victoria , Ecosystem
7.
Glob Chang Biol ; 29(15): 4397-4411, 2023 08.
Article in English | MEDLINE | ID: mdl-37300408

ABSTRACT

Biodiversity offsetting is a globally influential policy mechanism for reconciling trade-offs between development and biodiversity loss. However, there is little robust evidence of its effectiveness. We evaluated the outcomes of a jurisdictional offsetting policy (Victoria, Australia). Offsets under Victoria's Native Vegetation Framework (2002-2013) aimed to prevent loss and degradation of remnant vegetation, and generate gains in vegetation extent and quality. We categorised offsets into those with near-complete baseline woody vegetation cover ("avoided loss", 2702 ha) and with incomplete cover ("regeneration", 501 ha), and evaluated impacts on woody vegetation extent from 2008 to 2018. We used two approaches to estimate the counterfactual. First, we used statistical matching on biophysical covariates: a common approach in conservation impact evaluation, but which risks ignoring potentially important psychosocial confounders. Second, we compared changes in offsets with changes in sites that were not offsets for the study duration but were later enrolled as offsets, to partially account for self-selection bias (where landholders enrolling land may have shared characteristics affecting how they manage land). Matching on biophysical covariates, we estimated that regeneration offsets increased woody vegetation extent by 1.9%-3.6%/year more than non-offset sites (138-180 ha from 2008 to 2018) but this effect weakened with the second approach (0.3%-1.9%/year more than non-offset sites; 19-97 ha from 2008 to 2018) and disappeared when a single outlier land parcel was removed. Neither approach detected any impact of avoided loss offsets. We cannot conclusively demonstrate whether the policy goal of 'net gain' (NG) was achieved because of data limitations. However, given our evidence that the majority of increases in woody vegetation extent were not additional (would have happened without the scheme), a NG outcome seems unlikely. The results highlight the importance of considering self-selection bias in the design and evaluation of regulatory biodiversity offsetting policy, and the challenges of conducting robust impact evaluations of jurisdictional biodiversity offsetting policies.


Subject(s)
Biodiversity , Conservation of Natural Resources , Conservation of Natural Resources/methods , Wood , Motivation , Victoria , Ecosystem
8.
Nat Immunol ; 24(6): 1020-1035, 2023 06.
Article in English | MEDLINE | ID: mdl-37127830

ABSTRACT

While regulatory T (Treg) cells are traditionally viewed as professional suppressors of antigen presenting cells and effector T cells in both autoimmunity and cancer, recent findings of distinct Treg cell functions in tissue maintenance suggest that their regulatory purview extends to a wider range of cells and is broader than previously assumed. To elucidate tumoral Treg cell 'connectivity' to diverse tumor-supporting accessory cell types, we explored immediate early changes in their single-cell transcriptomes upon punctual Treg cell depletion in experimental lung cancer and injury-induced inflammation. Before any notable T cell activation and inflammation, fibroblasts, endothelial and myeloid cells exhibited pronounced changes in their gene expression in both cancer and injury settings. Factor analysis revealed shared Treg cell-dependent gene programs, foremost, prominent upregulation of VEGF and CCR2 signaling-related genes upon Treg cell deprivation in either setting, as well as in Treg cell-poor versus Treg cell-rich human lung adenocarcinomas. Accordingly, punctual Treg cell depletion combined with short-term VEGF blockade showed markedly improved control of PD-1 blockade-resistant lung adenocarcinoma progression in mice compared to the corresponding monotherapies, highlighting a promising factor-based querying approach to elucidating new rational combination treatments of solid organ cancers.


Subject(s)
Neoplasms , T-Lymphocytes, Regulatory , Animals , Mice , Humans , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism , Tumor Microenvironment , Neoplasms/metabolism
9.
bioRxiv ; 2023 Mar 29.
Article in English | MEDLINE | ID: mdl-37034770

ABSTRACT

Two distinct fates, pluripotent epiblast (EPI) and primitive (extra-embryonic) endoderm (PrE), arise from common progenitor cells, the inner cell mass (ICM), in mammalian embryos. To study how these sister identities are forged, we leveraged embryonic (ES) and eXtraembryonic ENdoderm (XEN) stem cells - in vitro counterparts of the EPI and PrE. Bidirectional reprogramming between ES and XEN coupled with single-cell RNA and ATAC-seq analyses uncovered distinct rates, efficiencies and trajectories of state conversions, identifying drivers and roadblocks of reciprocal conversions. While GATA4-mediated ES-to-iXEN conversion was rapid and nearly deterministic, OCT4, KLF4 and SOX2-induced XEN-to-iPS reprogramming progressed with diminished efficiency and kinetics. The dominant PrE transcriptional program, safeguarded by Gata4, and globally elevated chromatin accessibility of EPI underscored the differential plasticities of the two states. Mapping in vitro trajectories to embryos revealed reprogramming in either direction tracked along, and toggled between, EPI and PrE in vivo states without transitioning through the ICM.

10.
Nat Biotechnol ; 41(12): 1746-1757, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36973557

ABSTRACT

Metacells are cell groupings derived from single-cell sequencing data that represent highly granular, distinct cell states. Here we present single-cell aggregation of cell states (SEACells), an algorithm for identifying metacells that overcome the sparsity of single-cell data while retaining heterogeneity obscured by traditional cell clustering. SEACells outperforms existing algorithms in identifying comprehensive, compact and well-separated metacells in both RNA and assay for transposase-accessible chromatin (ATAC) modalities across datasets with discrete cell types and continuous trajectories. We demonstrate the use of SEACells to improve gene-peak associations, compute ATAC gene scores and infer the activities of critical regulators during differentiation. Metacell-level analysis scales to large datasets and is particularly well suited for patient cohorts, where per-patient aggregation provides more robust units for data integration. We use our metacells to reveal expression dynamics and gradual reconfiguration of the chromatin landscape during hematopoietic differentiation and to uniquely identify CD4 T cell differentiation and activation states associated with disease onset and severity in a Coronavirus Disease 2019 (COVID-19) patient cohort.


Subject(s)
Chromatin , Epigenomics , Humans , Chromatin/genetics , Chromatin/metabolism , Genomics , CD4-Positive T-Lymphocytes/metabolism , Algorithms , Single-Cell Analysis
11.
Cureus ; 15(12): e51256, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38288186

ABSTRACT

This narrative review examines the complex connection between infectious diseases and their neurological effects. It provides a detailed analysis of recent instances and insights derived from various pathogens. As we explore the realm of infectious agents, including viruses, bacteria, parasites, and fungi, a thorough and diverse analysis reveals the intricacies of neurological problems. The review begins by examining viral infections, specifically focusing on how viruses invade the neurological system and its subsequent effects. Significant instances from recent widespread disease outbreaks function as instructive benchmarks, highlighting the progressing comprehension of these ever-changing interconnections. The article examines the complex pathophysiology of neurological problems caused by bacterial infections. It presents current cases that illustrate the various ways these complications might manifest and the difficulties faced in their therapeutic management. Parasitic and fungal infections, which are typically overlooked, are being carefully examined to emphasize their distinct role in causing neurological complications. The mentioned cases highlight the importance of being thoroughly aware of these less-explored areas ranging from protozoan parasites to opportunistic fungal infections. In addition to the immediate effects caused by infectious agents, the review investigates autoimmune responses activated by infections. It provides a detailed examination of specific instances that shed light on the complex relationship between viral triggers and future neurological problems. This text elaborates on the intricacy of autoimmune-related neurological issues, highlighting the necessity for a comprehensive approach to diagnosing and treating them. The narrative next redirects its attention to the diagnostic difficulties that arise when interpreting the neurological symptoms of viral disorders. This article provides a thorough examination of existing diagnostic tools, along with an investigation into new technologies that have the potential to improve our capacity to identify and comprehend complex presentations. This debate connects to the following examination of treatment methods, where current cases that showcase successful interventions are carefully examined to extract valuable insights into good clinical management. The discussion focuses on the public health implications of preventive efforts against infectious infections, including their neurological consequences. The story emphasizes the link between infectious diseases and overall societal health, advocating for a proactive strategy to reduce the impact of neurological complications. The abstract concludes by providing a prospective viewpoint, highlighting areas of research that still need to be addressed, and suggesting potential future avenues. This narrative review seeks to provide a comprehensive resource for physicians, researchers, and public health professionals dealing with the complex field of neurological manifestations in infectious diseases. It combines recent examples, synthesizes current information, and offers a holistic perspective.

12.
Cureus ; 15(12): e51038, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38269231

ABSTRACT

This narrative review explores the complex relationship between cancer medicines and cardiovascular health in the junction of oncology and cardiology, known as cardio-oncology. The study examines the historical development of cancer treatments and highlights the growing importance of cardiovascular problems in patient care. This text delves into the topic of cardiotoxicity, examining both conventional chemotherapeutic drugs like anthracyclines and more recent tyrosine kinase and immune checkpoint inhibitors. The complex molecular and cellular mechanisms that control cardiovascular problems are explained, including an understanding of how genetic predisposition influences an individual's sensitivity. The narrative expands into the crucial realm of risk stratification and evaluation, revealing advanced instruments for identifying cardiovascular risk in cancer patients. The importance of non-invasive imaging methods and biomarkers in early detection and continuous monitoring is emphasized. The prioritization of preventive tactics emphasizes the need to take proactive measures incorporating therapies to protect the heart throughout cancer treatment. It also highlights the significance of making lifestyle improvements to reduce risk factors. The narrative emphasizes the changing collaborative treatment environment, advocating for merging oncologists and cardiologists in a coordinated endeavor to maximize patient outcomes. In addition to clinical factors, the review explores the critical domain of patient education and support, acknowledging its crucial role in promoting informed decision-making and improving overall patient well-being. The latter portions of the text anticipate and consider upcoming treatments and existing research efforts that offer the potential for the future of cardio-oncology. This review seeks to provide a detailed viewpoint on the intricate connection between cancer treatments and cardiovascular well-being. Its objective is to encourage a more profound comprehension of the subject and prompt careful contemplation regarding the comprehensive care of cancer patients who confront the intricate difficulties presented by their treatment plans.

13.
Front Public Health ; 10: 1042880, 2022.
Article in English | MEDLINE | ID: mdl-36568770

ABSTRACT

Background: International travelers often experience travelers' diarrhea. However, there is paucity of data on whether self-reported gastrointestinal symptoms influence travelers' perceptions of adequacy of sanitation and hygiene services encountered during travel, and to what degree their travel plans, and overall trip experience are impacted. Methods: A cross-sectional face-to-face survey was conducted amongst international travelers in India. Data collected included socio-demographics, travel characteristics, self-reported occurrence and frequency/severity of gastrointestinal symptoms, perceptions of sanitation and hygiene encountered, and adverse effects of symptoms on travel plans and trip experiences. Chi-square tests and logistic regression were performed to describe differences and associations between categorical variables. Results: Of the 300 international travelers surveyed, 46.3% experienced diarrhea. At least two thirds of travelers perceived the quality of sanitation (67.0%) and hygiene (70.0%) encountered to be inadequate. Perceptions of inadequate sanitation (adjusted OR = 3.0; 95% CI 1.7-5.5) and poor hygiene (adjusted OR = 7.7; 95% CI 4.1-15.5) were higher among travelers who experienced diarrhea. Additionally, both higher likelihood of travel plans being affected (adjusted OR = 10.7; 95% CI 5.1-23.6) and adverse impacts on overall trip experience (adjusted OR = 2.8; 95% CI 1.4-5.8) were reported among those who experienced diarrhea. Conclusions: More than two thirds of travelers surveyed in India experienced inadequate sanitation and hygiene services, with perceptions influenced by occurrence and frequency of diarrhea. Self-reported diarrhea was also associated with adverse effects on travel plans and overall trip experience. While these results may seem intuitive, they have important implications and suggest that improving sanitation and hygiene standards in India could potentially enhance tourism.


Subject(s)
Diarrhea , Sanitation , Humans , Diarrhea/prevention & control , Cross-Sectional Studies , Travel , Hygiene , India
14.
Nat Cancer ; 3(11): 1367-1385, 2022 11.
Article in English | MEDLINE | ID: mdl-36344707

ABSTRACT

The most prominent homozygous deletions in cancer affect chromosome 9p21.3 and eliminate CDKN2A/B tumor suppressors, disabling a cell-intrinsic barrier to tumorigenesis. Half of 9p21.3 deletions, however, also encompass a type I interferon (IFN) gene cluster; the consequences of this co-deletion remain unexplored. To functionally dissect 9p21.3 and other large genomic deletions, we developed a flexible deletion engineering strategy, MACHETE (molecular alteration of chromosomes with engineered tandem elements). Applying MACHETE to a syngeneic mouse model of pancreatic cancer, we found that co-deletion of the IFN cluster promoted immune evasion, metastasis and immunotherapy resistance. Mechanistically, IFN co-deletion disrupted type I IFN signaling in the tumor microenvironment, leading to marked changes in infiltrating immune cells and escape from CD8+ T-cell surveillance, effects largely driven by the poorly understood interferon epsilon. These results reveal a chromosomal deletion that disables both cell-intrinsic and cell-extrinsic tumor suppression and provide a framework for interrogating large deletions in cancer and beyond.


Subject(s)
Interferons , Neoplasms , Animals , Mice , Chromosome Deletion , Chromosomes , Immune Evasion , Tumor Microenvironment/genetics , Tandem Repeat Sequences
15.
Nat Commun ; 13(1): 3652, 2022 06 25.
Article in English | MEDLINE | ID: mdl-35752636

ABSTRACT

Heterogeneity is a hallmark of cancer. The advent of single-cell technologies has helped uncover heterogeneity in a high-throughput manner in different cancers across varied contexts. Here we apply single-cell sequencing technologies to reveal inherent heterogeneity in assumptively monoclonal pancreatic cancer (PDAC) cell lines and patient-derived organoids (PDOs). Our findings reveal a high degree of both genomic and transcriptomic polyclonality in monolayer PDAC cell lines, custodial variation induced by growing apparently identical cell lines in different laboratories, and transcriptomic shifts in transitioning from 2D to 3D spheroid growth models. Our findings also call into question the validity of widely available immortalized, non-transformed pancreatic lines as contemporaneous "control" lines in experiments. We confirm these findings using a variety of independent assays, including but not limited to whole exome sequencing, single-cell copy number variation sequencing (scCNVseq), single-nuclei assay for transposase-accessible chromatin with sequencing, fluorescence in-situ hybridization, and single-cell RNA sequencing (scRNAseq). We map scRNA expression data to unique genomic clones identified by orthogonally-gathered scCNVseq data of these same PDAC cell lines. Further, while PDOs are known to reflect the cognate in vivo biology of the parental tumor, we identify transcriptomic shifts during ex vivo passage that might hamper their predictive abilities over time. The impact of these findings on rigor and reproducibility of experimental data generated using established preclinical PDAC models between and across laboratories is uncertain, but a matter of concern.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , DNA Copy Number Variations/genetics , Humans , Pancreas/metabolism , Pancreatic Neoplasms/pathology , Reproducibility of Results , Pancreatic Neoplasms
16.
Drug Res (Stuttg) ; 72(4): 189-196, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35176795

ABSTRACT

Dopamine is secreted by the hypothalamus, which inhibits the proliferation and effectiveness of lactotroph cells that release prolactin via dopamine D2 receptor (D2R). D2R activation inhibits lactotroph cell prolactin synthesis and regulates prolactin gene expression. Although, commercial medications are available for hypogalactia and agalactia, various plant sources significantly alleviate these problems. Leptadenia reticulata (Jivanti) is one of the important medicinal plants often consumed by nursing mothers to improve breast milk production. However, mechanism and chemical constituents involved in the inhibition of D2R by Jivanti is unclear. Therefore, in this study the phytocompounds reported from Jivanti were used for in-silico analysis to predict D2R inhibitory potential. The binding affinity value of campesterol and ß-sitosterol (- 10.1 and -10.0 kcal/mol) with D2R has high revealed by molecular docking and stable interaction reveled by molecular dynamics simulation. Thus, these lead compounds could exert more D2R inhibitory activity resulting into prolactin release, which may lead to an increase in breast milk production. Although all selected compounds had fine permeation, non-toxic, and non-carcinogenic characteristics predicted by ADMET, campesterol had good solubility, absorption characteristics compared to other. Therefore, Jivanti, which is traditionally known medicinal plant, could be explored as a medication candidate to boost breast milk production.


Subject(s)
Apocynaceae , Plants, Medicinal , Female , Humans , Molecular Docking Simulation , Prolactin , Receptors, Dopamine D2/genetics , Receptors, Dopamine D2/metabolism
17.
Transgenic Res ; 30(4): 585-599, 2021 08.
Article in English | MEDLINE | ID: mdl-33721140

ABSTRACT

CRISPR-Cas9 is a revolutionary technology because it is precise, fast and easy to implement, cheap and components are readily accessible. This versatility means that the technology can deliver a timely end product and can be used by many stakeholders. In plant cells, the technology can be applied to knockout genes by using CRISPR-Cas nucleases that can alter coding gene regions or regulatory elements, alter precisely a genome by base editing to delete or regulate gene expression, edit precisely a genome by homology-directed repair mechanism (cellular DNA), or regulate transcriptional machinery by using dead Cas proteins to recruit regulators to the promoter region of a gene. All these applications can be for: 1) Research use (Non commercial), 2) Uses related product components for the technology itself (reagents, equipment, toolkits, vectors etc), and 3) Uses related to the development and sale of derived end products based on this technology. In this contribution, we present a prototype report that can engage the community in open, inclusive and collaborative innovation mapping. Using the open data at the Lens.org platform and other relevant sources, we tracked, analyzed, organized, and assembled contextual and bridged patent and scholarly knowledge about CRISPR-Cas9 and with the assistance of a new Lens institutional capability, The Lens Report Builder, currently in beta release, mapped the public and commercial innovation pathways of the technology. When scaled, this capability will also enable coordinated editing and curation by credentialed experts to inform policy makers, businesses and private or public investment.


Subject(s)
CRISPR-Cas Systems , Crops, Agricultural/genetics , Gene Editing , Genome, Plant , Inventions/statistics & numerical data , Private Sector , Public Sector , Commerce , Gene Targeting , Humans
19.
Ann Rheum Dis ; 80(2): 228-237, 2021 02.
Article in English | MEDLINE | ID: mdl-33028580

ABSTRACT

OBJECTIVE: We sought to determine histologic and gene expression features of clinical improvement in early diffuse cutaneous systemic sclerosis (dcSSc; scleroderma). METHODS: Fifty-eight forearm biopsies were evaluated from 26 individuals with dcSSc in two clinical trials. Histologic/immunophenotypic assessments of global severity, alpha-smooth muscle actin (aSMA), CD34, collagen, inflammatory infiltrate, follicles and thickness were compared with gene expression and clinical data. Support vector machine learning was performed using scleroderma gene expression subset (normal-like, fibroproliferative, inflammatory) as classifiers and histology scores as inputs. Comparison of w-vector mean absolute weights was used to identify histologic features most predictive of gene expression subset. We then tested for differential gene expression according to histologic severity and compared those with clinical improvement (according to the Combined Response Index in Systemic Sclerosis). RESULTS: aSMA was highest and CD34 lowest in samples with highest local Modified Rodnan Skin Score. CD34 and aSMA changed significantly from baseline to 52 weeks in clinical improvers. CD34 and aSMA were the strongest predictors of gene expression subset, with highest CD34 staining in the normal-like subset (p<0.001) and highest aSMA staining in the inflammatory subset (p=0.016). Analysis of gene expression according to CD34 and aSMA binarised scores identified a 47-gene fibroblast polarisation signature that decreases over time only in improvers (vs non-improvers). Pathway analysis of these genes identified gene expression signatures of inflammatory fibroblasts. CONCLUSION: CD34 and aSMA stains describe distinct fibroblast polarisation states, are associated with gene expression subsets and clinical assessments, and may be useful biomarkers of clinical severity and improvement in dcSSc.


Subject(s)
Fibroblasts/physiology , Machine Learning , Scleroderma, Diffuse/genetics , Severity of Illness Index , Actins/metabolism , Adult , Antigens, CD34/metabolism , Clinical Trials as Topic , Collagen/metabolism , Female , Forearm , Gene Expression , Humans , Male , Middle Aged , Skin/metabolism
20.
J Am Heart Assoc ; 9(19): e017789, 2020 10 20.
Article in English | MEDLINE | ID: mdl-33006292

ABSTRACT

Background Atrial fibrillation (AF) driver mechanisms are obscured to clinical multielectrode mapping approaches that provide partial, surface-only visualization of unstable 3-dimensional atrial conduction. We hypothesized that transient modulation of refractoriness by pharmacologic challenge during multielectrode mapping improves visualization of hidden paths of reentrant AF drivers for targeted ablation. Methods and Results Pharmacologic challenge with adenosine was tested in ex vivo human hearts with a history of AF and cardiac diseases by multielectrode and high-resolution subsurface near-infrared optical mapping, integrated with 3-dimensional structural imaging and heart-specific computational simulations. Adenosine challenge was also studied on acutely terminated AF drivers in 10 patients with persistent AF. Ex vivo, adenosine stabilized reentrant driver paths within arrhythmogenic fibrotic hubs and improved visualization of reentrant paths, previously seen as focal or unstable breakthrough activation pattern, for targeted AF ablation. Computational simulations suggested that shortening of atrial refractoriness by adenosine may (1) improve driver stability by annihilating spatially unstable functional blocks and tightening reentrant circuits around fibrotic substrates, thus unmasking the common reentrant path; and (2) destabilize already stable reentrant drivers along fibrotic substrates by accelerating competing fibrillatory wavelets or secondary drivers. In patients with persistent AF, adenosine challenge unmasked hidden common reentry paths (9/15 AF drivers, 41±26% to 68±25% visualization), but worsened visualization of previously visible reentry paths (6/15, 74±14% to 34±12%). AF driver ablation led to acute termination of AF. Conclusions Our ex vivo to in vivo human translational study suggests that transiently altering atrial refractoriness can stabilize reentrant paths and unmask arrhythmogenic hubs to guide targeted AF driver ablation treatment.


Subject(s)
Atrial Fibrillation/etiology , Heart/physiopathology , Adenosine/pharmacology , Adult , Atrial Fibrillation/pathology , Atrial Fibrillation/physiopathology , Female , Heart/drug effects , Heart Atria/pathology , Heart Atria/physiopathology , Humans , Imaging, Three-Dimensional , Male , Microelectrodes , Middle Aged , Myocardium/pathology , Voltage-Sensitive Dye Imaging
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