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1.
Cell ; 185(10): 1777-1792.e21, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35512705

RESUMO

Spatially resolved transcriptomic technologies are promising tools to study complex biological processes such as mammalian embryogenesis. However, the imbalance between resolution, gene capture, and field of view of current methodologies precludes their systematic application to analyze relatively large and three-dimensional mid- and late-gestation embryos. Here, we combined DNA nanoball (DNB)-patterned arrays and in situ RNA capture to create spatial enhanced resolution omics-sequencing (Stereo-seq). We applied Stereo-seq to generate the mouse organogenesis spatiotemporal transcriptomic atlas (MOSTA), which maps with single-cell resolution and high sensitivity the kinetics and directionality of transcriptional variation during mouse organogenesis. We used this information to gain insight into the molecular basis of spatial cell heterogeneity and cell fate specification in developing tissues such as the dorsal midbrain. Our panoramic atlas will facilitate in-depth investigation of longstanding questions concerning normal and abnormal mammalian development.


Assuntos
Organogênese , Transcriptoma , Animais , DNA/genética , Embrião de Mamíferos , Feminino , Perfilação da Expressão Gênica/métodos , Mamíferos/genética , Camundongos , Organogênese/genética , Gravidez , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Transcriptoma/genética
2.
Cell ; 177(6): 1419-1435.e31, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31056281

RESUMO

Horse domestication revolutionized warfare and accelerated travel, trade, and the geographic expansion of languages. Here, we present the largest DNA time series for a non-human organism to date, including genome-scale data from 149 ancient animals and 129 ancient genomes (≥1-fold coverage), 87 of which are new. This extensive dataset allows us to assess the modern legacy of past equestrian civilizations. We find that two extinct horse lineages existed during early domestication, one at the far western (Iberia) and the other at the far eastern range (Siberia) of Eurasia. None of these contributed significantly to modern diversity. We show that the influence of Persian-related horse lineages increased following the Islamic conquests in Europe and Asia. Multiple alleles associated with elite-racing, including at the MSTN "speed gene," only rose in popularity within the last millennium. Finally, the development of modern breeding impacted genetic diversity more dramatically than the previous millennia of human management.


Assuntos
Cavalos/genética , Animais , Ásia , Evolução Biológica , Cruzamento/história , DNA Antigo/análise , Domesticação , Equidae/genética , Europa (Continente) , Feminino , Variação Genética/genética , Genoma/genética , História Antiga , Masculino , Filogenia
3.
Immunity ; 52(2): 404-416.e5, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32049054

RESUMO

Mast cells are rare tissue-resident cells of importance to human allergies. To understand the structural basis of principle mast cell functions, we analyzed the proteome of primary human and mouse mast cells by quantitative mass spectrometry. We identified a mast-cell-specific proteome signature, indicative of a unique lineage, only distantly related to other immune cell types, including innate immune cells. Proteome comparison between human and mouse suggested evolutionary conservation of core mast cell functions. In addition to specific proteases and proteins associated with degranulation and proteoglycan biosynthesis, mast cells expressed proteins potentially involved in interactions with neurons and neurotransmitter metabolism, including cell adhesion molecules, ion channels, and G protein coupled receptors. Toward targeted cell ablation in severe allergic diseases, we used MRGPRX2 for mast cell depletion in human skin biopsies. These proteome analyses suggest a unique role of mast cells in the immune system, probably intertwined with the nervous system.


Assuntos
Mastócitos/citologia , Mastócitos/imunologia , Animais , Biomarcadores/metabolismo , Degranulação Celular , Linhagem da Célula , Células Cultivadas , Tecido Conjuntivo/imunologia , Humanos , Imunoterapia , Mastócitos/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/imunologia , Proteínas do Tecido Nervoso/metabolismo , Neuroimunomodulação , Proteoglicanas/biossíntese , Proteoma , Receptores Acoplados a Proteínas G/imunologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropeptídeos/imunologia , Receptores de Neuropeptídeos/metabolismo , Pele/imunologia
4.
Annu Rev Genet ; 54: 511-537, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-32926793

RESUMO

Tuberculosis claims more human lives than any other bacterial infectious disease and represents a clear and present danger to global health as new tools for vaccination, treatment, and interruption of transmission have been slow to emerge. Additionally, tuberculosis presents with notable clinical heterogeneity, which complicates diagnosis, treatment, and the establishment of nonrelapsing cure. How this heterogeneity is driven by the diversity ofclinical isolates of the causative agent, Mycobacterium tuberculosis, has recently garnered attention. Herein, we review advances in the understanding of how naturally occurring variation in clinical isolates affects transmissibility, pathogenesis, immune modulation, and drug resistance. We also summarize how specific changes in transcriptional responses can modulate infection or disease outcome, together with strain-specific effects on gene essentiality. Further understanding of how this diversity of M. tuberculosis isolates affects disease and treatment outcomes will enable the development of more effective therapeutic options and vaccines for this dreaded disease.


Assuntos
Variação Genética/genética , Mycobacterium tuberculosis/genética , Animais , Genótipo , Humanos , Transcrição Gênica/genética , Tuberculose/microbiologia
5.
Trends Genet ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38853120

RESUMO

The complexity of the brain is closely tied to its nature as a genetic mosaic, wherein each cell is distinguished by a unique constellation of somatic variants that contribute to functional and phenotypic diversity. Postzygotic variation arising during neurogenesis is recognized as a key contributor to brain mosaicism; however, recent advances have broadened our understanding to include sources of neural genomic diversity that develop throughout the entire lifespan, from embryogenesis through aging. Moving beyond the traditional confines of neurodevelopment, in this review, we delve into the complex mechanisms that enable various origins of brain mosaicism.

6.
Mol Biol Evol ; 41(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39107250

RESUMO

Crop disease pandemics are often driven by asexually reproducing clonal lineages of plant pathogens that reproduce asexually. How these clonal pathogens continuously adapt to their hosts despite harboring limited genetic variation, and in absence of sexual recombination remains elusive. Here, we reveal multiple instances of horizontal chromosome transfer within pandemic clonal lineages of the blast fungus Magnaporthe (Syn. Pyricularia) oryzae. We identified a horizontally transferred 1.2Mb accessory mini-chromosome which is remarkably conserved between M. oryzae isolates from both the rice blast fungus lineage and the lineage infecting Indian goosegrass (Eleusine indica), a wild grass that often grows in the proximity of cultivated cereal crops. Furthermore, we show that this mini-chromosome was horizontally acquired by clonal rice blast isolates through at least nine distinct transfer events over the past three centuries. These findings establish horizontal mini-chromosome transfer as a mechanism facilitating genetic exchange among different host-associated blast fungus lineages. We propose that blast fungus populations infecting wild grasses act as genetic reservoirs that drive genome evolution of pandemic clonal lineages that afflict cereal crops.


Assuntos
Evolução Molecular , Transferência Genética Horizontal , Cromossomos Fúngicos/genética , Ascomicetos/genética , Doenças das Plantas/microbiologia , Genoma Fúngico
7.
J Virol ; 98(6): e0051324, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38752754

RESUMO

Marseilleviruses (MsV) are a group of viruses that compose the Marseilleviridae family within the Nucleocytoviricota phylum. They have been found in different samples, mainly in freshwater. MsV are classically organized into five phylogenetic lineages (A/B/C/D/E), but the current taxonomy does not fully represent all the diversity of the MsV lineages. Here, we describe a novel strain isolated from a Brazilian saltwater sample named Marseillevirus cajuinensis. Based on genomics and phylogenetic analyses, M. cajuinensis exhibits a 380,653-bp genome that encodes 515 open reading frames. Additionally, M. cajuinensis encodes a transfer RNA, a feature that is rarely described for Marseilleviridae. Phylogeny suggests that M. cajuinensis forms a divergent branch within the MsV lineage A. Furthermore, our analysis suggests that the common ancestor for the five classical lineages of MsV diversified into three major groups. The organization of MsV into three main groups is reinforced by a comprehensive analysis of clusters of orthologous groups, sequence identities, and evolutionary distances considering several MsV isolates. Taken together, our results highlight the importance of discovering new viruses to expand the knowledge about known viruses that belong to the same lineages or families. This work proposes a new perspective on the Marseilleviridae lineages organization that could be helpful to a future update in the taxonomy of the Marseilleviridae family. IMPORTANCE: Marseilleviridae is a family of viruses whose members were mostly isolated from freshwater samples. In this work, we describe the first Marseillevirus isolated from saltwater samples, which we called Marseillevirus cajuinensis. Most of M. cajuinensis genomic features are comparable to other Marseilleviridae members, such as its high number of unknown proteins. On the other hand, M. cajuinensis encodes a transfer RNA, which is a gene category involved in protein translation that is rarely described in this viral family. Additionally, our phylogenetic analyses suggested the existence of, at least, three major Marseilleviridae groups. These observations provide a new perspective on Marseilleviridae lineages organization, which will be valuable in future updates to the taxonomy of the family since the current official classification does not capture all the Marseilleviridae known diversity.


Assuntos
Genoma Viral , Vírus , Brasil , Evolução Molecular , Genômica/métodos , Fases de Leitura Aberta , Filogenia , RNA Viral/genética , Vírus/classificação , Vírus/genética
8.
Immunol Rev ; 303(1): 52-61, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34313339

RESUMO

Antibody-secreting plasma cells are a central component of short- and long-term adaptive immunity. Yet, many fundamental questions about how activated B cells decide to yield functional plasma cells have yet to be answered. Likewise, the biochemical processes underpinning the ability of plasma cells to generate and secrete large numbers of antibodies, the capacity of some plasma cell to sustain antibody secretion, presumably without interruption, for decades, and the capacity of long-lived plasma cells to avoid apoptosis despite the high-energy demands associated with sustained robust antibody synthesis and secretion each remain mysterious processes. Our objective here is to review what is currently known about these processes with an emphasis on the earliest phases of plasma cell genesis. Along the way, we will work toward developing a model that ties the biochemistry of plasma cell function and survival. The chief idea imbedded in this model is that progress toward understanding plasma cell survival mechanisms may require increased focus on the unique cell autonomous processes inherent in plasma cell differentiation and function.


Assuntos
Linfócitos B , Plasmócitos , Formação de Anticorpos , Células Produtoras de Anticorpos , Diferenciação Celular , Ativação Linfocitária
9.
Immunol Rev ; 300(1): 152-166, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33559175

RESUMO

Since their discovery a decade ago, it has become evident that innate lymphoid cells (ILCs) play critical roles in protective immune responses against intracellular and extracellular pathogens but are also central regulators of epithelial barrier integrity and tissue homeostasis. ILCs populate almost every tissue in mammalian organisms; therefore, not surprisingly, dysregulation of their functions contributes to the development and progression of multiple inflammatory and metabolic diseases. Our knowledge of the transcriptional programs governing the development, differentiation, and functions of the different groups of ILCs has increased dramatically in the last ten years. However, with the advent of new technologies, an unprecedented level of heterogeneity, plasticity, and developmental complexity has started to be revealed. In this review, we highlight recent advances in our understanding of ILC development and their biological functions. In particular, we aim to emphasize how our increasing knowledge of the chromatin landscape and the noncoding genome of these innate lymphocytes is allowing us to better understand their development and functions in different contexts during homeostasis and inflammation. Moreover, we propose that the design of more refined genetic tools to study tissue-specific ILCs and their functions can be accomplished by leveraging our understanding of how specific noncoding elements of the genome regulate gene expression in ILCs.


Assuntos
Imunidade Inata , Linfócitos , Animais , Diferenciação Celular , Homeostase , Imunidade Inata/genética , Inflamação
10.
Immunol Rev ; 301(1): 84-97, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33559209

RESUMO

While the existence of a special relationship between Mycobacterium tuberculosis (Mtb) and host lipids has long been known, it remains a challenging enigma. It was clearly established that Mtb requires host fatty acids (FAs) and cholesterol to produce energy, build its distinctive lipid-rich cell wall, and produce lipid virulence factors. It was also observed that in infected hosts, Mtb constantly resides in a FA-rich environment that the pathogen contributes to generate by inducing a lipid-laden "foamy" phenotype in host macrophages. These observations and the proximity between lipid droplets and phagosomes containing bacteria within infected macrophages gave rise to the hypothesis that Mtb reprograms host cell lipid metabolism to ensure a continuous supply of essential nutrients and its long-term persistence in vivo. However, recent studies question this principle by indicating that in Mtb-infected macrophages, lipid droplet formation prevents bacterial acquisition of host FAs while supporting the production of FA-derived protective lipid mediators. Further, in vivo investigations reveal discrete macrophage phenotypes linking the FA metabolisms of host cell and intracellular pathogen. Notably, FA storage within lipid droplets characterizes both macrophages controlling Mtb infection and dormant intracellular Mtb. In this review, we integrate findings from immunological and microbiological studies illustrating the new concept that cytoplasmic accumulation of FAs is a metabolic adaptation of macrophages to Mtb infection, which potentiates their antimycobacterial responses and forces the intracellular pathogen to shift into fat-saving, survival mode.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Ácidos Graxos , Interações Hospedeiro-Patógeno , Humanos , Metabolismo dos Lipídeos , Macrófagos
11.
Immunol Rev ; 300(1): 65-81, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33615514

RESUMO

Once alerted to the presence of a pathogen, activated CD4+ T cells initiate distinct gene expression programs that produce multiple functionally specialized T helper (Th) subsets. The cytokine milieu present at the time of antigen encounter instructs CD4+ T cells to differentiate into interferon-(IFN)-γ-producing Th1 cells, interleukin-(IL)-4-producing Th2 cells, IL-17-producing Th17 cells, follicular T helper (Tfh) cells, or regulatory T (Treg) cells. In each of these Th cell subsets, a single transcription factor has been identified as a critical regulator of its specialized differentiation program. In this context, the expression of the "master regulator" is necessary and sufficient to activate lineage-specific genes while restricting the gene expression program of alternative Th fates. Thus, the transcription factor T-bet controls Th1 differentiation program, while the development of Th2, Th17, Tfh, and Treg cells is dependent on transcription factors GATA3, RORγt, Bcl6, and Foxp3, respectively. Nevertheless, master regulators or, more precisely, lineage-defining transcription factors do not function in isolation. In fact, they interact with a complex network of transcription factors, orchestrating cell lineage specification programs. In this review, we discuss the concept of the combinatorial interactions of key transcription factors in determining helper T cell identity. Additionally, lineage-defining transcription factors have well-established functions beyond their role in CD4+ Th subsets. They play critically important functions at distinct stages during T cell development in the thymus and they control the development of innate lymphoid cells (ILCs) in the bone marrow. In tracking the journey of T cells traversing from the thymus to the periphery and during the immune response, we discuss in broad terms developmental stage and context-dependent functions of lineage-defining transcription factors in regulating specification programs of innate and adaptive lymphocytes.


Assuntos
Imunidade Inata , Linfócitos T Reguladores , Linhagem da Célula/genética , Regulação da Expressão Gênica , Células Th17
12.
J Infect Dis ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39116351

RESUMO

We report a single case of invasive pneumococcal disease (IPD) by serotype 4, multilocus sequence type 10172 (serotype 4/ST10172) isolate with vanG-type resistance genes and reduced vancomycin susceptibility. The isolate was recovered during 2022 from a 66-year-old resident with bacteremic pneumococcal pneumonia within a CDC Active Bacterial Core surveillance (ABCs) site hospital. The patient had received 23-valent pneumococcal polysaccharide vaccine and there was no evidence of concurrent or prior receipt of vancomycin in the previous year. Serotype 4/ST10172 IPD has shown increases within western ABCs sites and the recent acquisition of a vanG element warrants close monitoring of this lineage.

13.
J Infect Dis ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38547499

RESUMO

Enterovirus D68 (EV-D68) infections are associated with severe respiratory disease and acute flaccid myelitis (AFM). The European Non-Polio Enterovirus Network (ENPEN) aimed to investigate the epidemiological and genetic characteristics of EV-D68 and its clinical impact during the fall-winter season of 2021/22. From 19 European countries, 58 institutes reported 10,481 (6.8%) EV-positive samples of which 1,004 (9.6%) were identified as EV-D68 (852 respiratory samples). Clinical data was reported for 969 cases. 78.9% of infections were reported in children (0-5 years); 37.9% of cases were hospitalised. Acute respiratory distress was commonly noted (93.1%) followed by fever (49.4%). Neurological problems were observed in 6.4% of cases with six reported with AFM. Phylodynamic/Nextstrain and phylogenetic analyses based on 694 sequences showed the emergence of two novel B3-derived lineages, with no regional clustering. In conclusion, we describe a large-scale EV-D68 European upsurge with severe clinical impact and the emergence of B3-derived lineages.

14.
Emerg Infect Dis ; 30(8): 1729-1732, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39043427

RESUMO

Vibrio mimicus bacteria have caused sporadic cases and outbreaks of cholera-like diarrhea throughout the world, but the association of lineages with such events is unexplored. Genomic analyses revealed V. mimicus lineages carrying the virulence factors cholera toxin and toxin coregulated pilus, one of which has persisted for decades in China and the United States.


Assuntos
Toxina da Cólera , Ilhas Genômicas , Vibrio mimicus , China/epidemiologia , Humanos , Vibrio mimicus/genética , Vibrio mimicus/patogenicidade , Estados Unidos/epidemiologia , Toxina da Cólera/genética , Cólera/microbiologia , Cólera/epidemiologia , Filogenia , Vibrioses/microbiologia , Vibrioses/epidemiologia , Fatores de Virulência/genética
15.
EMBO J ; 39(4): e102675, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-31943281

RESUMO

Site-specific recombinase-mediated genetic technology, such as inducible Cre-loxP recombination (CreER), is widely used for in vivo genetic manipulation with temporal control. The Cre-loxP technology improves our understanding on the in vivo function of specific genes in organ development, tissue regeneration, and disease progression. However, inducible CreER often remains inefficient in gene deletion. In order to improve the efficiency of gene manipulation, we generated a self-cleaved inducible CreER (sCreER) that switches inducible CreER into a constitutively active Cre by itself. We generated endocardial driver Npr3-sCreER and fibroblast driver Col1a2-sCreER, and compared them with conventional Npr3-CreER and Col1a2-CreER, respectively. For easy-to-recombine alleles such as R26-tdTomato, there was no significant difference in recombination efficiency between sCreER and the conventional CreER. However, for alleles that were relatively inert for recombination such as R26-Confetti, R26-LZLT, R26-GFP, or VEGFR2flox/flox alleles, sCreER showed a significantly higher efficiency in recombination compared with conventional CreER in endocardial cells or fibroblasts. Compared with conventional CreER, sCreER significantly enhances the efficiency of recombination to induce gene expression or gene deletion, allowing temporal yet effective in vivo genomic modification for studying gene function in specific cell lineages.


Assuntos
Integrases/genética , Recombinação Genética , Alelos , Animais , Linhagem da Célula , Feminino , Fibroblastos , Deleção de Genes , Expressão Gênica , Integrases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
16.
Mol Ecol ; 33(7): e17304, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38421113

RESUMO

Glacial cycles lead to periodic population interbreeding and isolation in warm-adapted species, which impact genetic structure and evolution. However, the effects of these processes on highly mobile and more cold-tolerant species are not well understood. This study aims to shed light on the phylogeographic history of Aglais urticae, a butterfly species with considerable dispersal ability, and a wide Palearctic distribution reaching the Arctic. Through the analysis of genomic data, four main genetic lineages are identified: European, Sierra Nevada, Sicily/Calabria/Peloponnese, and Eastern. The results indicate that the Sardo-Corsican endemic taxon ichnusa is a distinct species. The split between the relict lineages in southern Europe and the main European lineage is estimated to have happened 400-450 thousand years ago, with admixture observed during the Quaternary glacial cycles, and still ongoing, albeit to a much smaller extent. These results suggest that these lineages may be better treated as subspecific parapatric taxa. Ecological niche modelling supported the existence of both Mediterranean and extra-Mediterranean refugia during the glacial periods, with the main one located on the Atlantic coast. Nevertheless, gene flow between populations was possible, indicating that both differentiation and admixture have acted continuously across glacial cycles in this cold-tolerant butterfly, generally balancing each other but producing differentiated lineages in the southern peninsulas. We conclude that the population dynamics and the processes shaping the population genetic structure of cold-adapted species during the Quaternary ice ages may be different than those classically accepted for warm-adapted species.


Assuntos
Borboletas , Variação Genética , Animais , Filogenia , Variação Genética/genética , Borboletas/genética , Filogeografia , Europa (Continente)
17.
Mol Ecol ; : e17508, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39161130

RESUMO

Genome-wide technologies open up new possibilities to clarify questions on genetic structure and phylogeographic history of taxa previously studied with microsatellite loci and mitochondrial sequences. Here, we used 736 individual red deer (Cervus elaphus) samples genotyped at 35,701 single nucleotide polymorphism loci (SNPs) to assess the population structure of the species throughout Europe. The results identified 28 populations, with higher degrees of genetic distinction in peripheral compared to mainland populations. Iberian red deer show high genetic differentiation, with lineages in Western and Central Iberia maintaining their distinctiveness, which supports separate refugial ranges within Iberia along with little recent connection between Iberian and the remaining Western European populations. The Norwegian population exhibited the lowest variability and the largest allele frequency differences from mainland European populations, compatible with a history of bottlenecks and drift during post-glacial colonization from southern refugia. Scottish populations showed high genetic distance from the mainland but high levels of diversity. Hybrid zones were found between Eastern and Western European lineages in Central Europe as well as in the Pyrenees, where red deer from France are in close contact with Iberian red deer. Anthropogenic restocking has promoted the Pyrenean contact zone, admixture events in populations on the Isle of Rum and in the Netherlands, and at least partly the admixture of the two main lineages in central-eastern Europe. Our analysis enabled detailed resolution of population structure of a large mammal widely distributed throughout Europe and contributes to resolving the evolutionary history, which can also inform conservation and management policies.

18.
Hum Genomics ; 17(1): 58, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420264

RESUMO

BACKGROUND: Wastewater-based epidemiological surveillance has been considered a powerful tool for early detection and monitoring of the dynamics of SARS-CoV-2 and its lineages circulating in a community. This study is aimed to investigate the complexity of SARS-CoV-2 infection dynamics in Dhaka city by examining its genetic variants in wastewater. Also, the study seeks to determine a connection between the SARS-CoV-2 variations detected in clinical testing and those found in wastewater samples. RESULTS: Out of 504 samples tested in RT-qPCR, 185 (36.7%) tested positive for SARS-CoV-2 viral RNA. The median log10 concentration of SARS-CoV-2 N gene copies/Liter of wastewater (gc/L) was 5.2, and the median log10 concentration of ORF1ab was 4.9. To further reveal the genetic diversity of SARS-CoV-2, ten samples with ORF1ab real-time RT-PCR cycle threshold (Ct) values ranging from 28.78 to 32.13 were subjected to whole genome sequencing using nanopore technology. According to clade classification, sequences from wastewater samples were grouped into 4 clades: 20A, 20B, 21A, 21J, and the Pango lineage, B.1, B.1.1, B.1.1.25, and B.1.617.2, with coverage ranging from 94.2 to 99.8%. Of them, 70% belonged to clade 20B, followed by 10% to clade 20A, 21A, and 21J. Lineage B.1.1.25 was predominant in Bangladesh and phylogenetically related to the sequences from India, the USA, Canada, the UK, and Italy. The Delta variant (B.1.617.2) was first identified in clinical samples at the beginning of May 2021. In contrast, we found that it was circulating in the community and was detected in wastewater in September 2020. CONCLUSION: Environmental surveillance is useful for monitoring temporal and spatial trends of existing and emerging infectious diseases and supports evidence-based public health measures. The findings of this study supported the use of wastewater-based epidemiology and provided the baseline data for the dynamics of SARS-CoV-2 variants in the wastewater environment in Dhaka, Bangladesh.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Bangladesh/epidemiologia , COVID-19/epidemiologia , Vigilância em Saúde Pública , Águas Residuárias , Proteínas do Sistema Complemento , RNA
19.
Cell Commun Signal ; 22(1): 330, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879537

RESUMO

Sex-specific gonadal differentiation is directed by complex signalling promoting development in either male or female direction, while simultaneously inhibiting the opposite pathway. In mice, the WNT/ß-catenin pathway promotes ovarian development and the importance of actively inhibiting this pathway to ensure normal testis development has been recognised. However, the implications of alterations in the tightly regulated WNT/ß-catenin signalling during human fetal gonad development has not yet been examined in detail. Thus, the aim of this study was to examine the consequences of dysregulating the WNT/ß-catenin signalling pathway in the supporting cell lineage during sex-specific human fetal gonad development using an established and extensively validated ex vivo culture model. Inhibition of WNT/ß-catenin signalling in human fetal ovary cultures resulted in only minor effects, including reduced secretion of RSPO1 and reduced cell proliferation although this was not consistently found in all treatment groups. In contrast, promotion of WNT/ß-catenin signalling in testes severely affected development and function. This included disrupted seminiferous cord structures, reduced cell proliferation, reduced expression of SOX9/AMH, reduced secretion of Inhibin B and AMH as well as loss of the germ cell population. Additionally, Leydig cell function was markedly impaired with reduced secretion of testosterone, androstenedione and INSL3. Together, this study suggests that dysregulated WNT/ß-catenin signalling during human fetal gonad development severely impairs testicular development and function. Importantly, our study highlights the notion that sufficient inhibition of the opposite pathway during sex-specific gonadal differentiation is essential to ensure normal development and function also applies to human fetal gonads.


Assuntos
Testículo , Via de Sinalização Wnt , Humanos , Masculino , Testículo/metabolismo , Testículo/embriologia , Feminino , Diferenciação Sexual/genética , Feto/metabolismo , Diferenciação Celular , Proliferação de Células , beta Catenina/metabolismo , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/citologia , Ovário/metabolismo , Ovário/embriologia
20.
Biometrics ; 80(1)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38364812

RESUMO

People living with HIV on antiretroviral therapy often have undetectable virus levels by standard assays, but "latent" HIV still persists in viral reservoirs. Eliminating these reservoirs is the goal of HIV cure research. The quantitative viral outgrowth assay (QVOA) is commonly used to estimate the reservoir size, that is, the infectious units per million (IUPM) of HIV-persistent resting CD4+ T cells. A new variation of the QVOA, the ultra deep sequencing assay of the outgrowth virus (UDSA), was recently developed that further quantifies the number of viral lineages within a subset of infected wells. Performing the UDSA on a subset of wells provides additional information that can improve IUPM estimation. This paper considers statistical inference about the IUPM from combined dilution assay (QVOA) and deep viral sequencing (UDSA) data, even when some deep sequencing data are missing. Methods are proposed to accommodate assays with wells sequenced at multiple dilution levels and with imperfect sensitivity and specificity, and a novel bias-corrected estimator is included for small samples. The proposed methods are evaluated in a simulation study, applied to data from the University of North Carolina HIV Cure Center, and implemented in the open-source R package SLDeepAssay.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Latência Viral , HIV-1/genética , Linfócitos T CD4-Positivos , Simulação por Computador , Carga Viral
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