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1.
Cell ; 187(14): 3563-3584.e26, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38889727

RESUMO

How evolution at the cellular level potentiates macroevolutionary change is central to understanding biological diversification. The >66,000 rove beetle species (Staphylinidae) form the largest metazoan family. Combining genomic and cell type transcriptomic insights spanning the largest clade, Aleocharinae, we retrace evolution of two cell types comprising a defensive gland-a putative catalyst behind staphylinid megadiversity. We identify molecular evolutionary steps leading to benzoquinone production by one cell type via a mechanism convergent with plant toxin release systems, and synthesis by the second cell type of a solvent that weaponizes the total secretion. This cooperative system has been conserved since the Early Cretaceous as Aleocharinae radiated into tens of thousands of lineages. Reprogramming each cell type yielded biochemical novelties enabling ecological specialization-most dramatically in symbionts that infiltrate social insect colonies via host-manipulating secretions. Our findings uncover cell type evolutionary processes underlying the origin and evolvability of a beetle chemical innovation.


Assuntos
Besouros , Animais , Besouros/genética , Besouros/metabolismo , Evolução Molecular , Benzoquinonas/metabolismo , Filogenia , Genômica , Simbiose/genética , Transcriptoma , Genoma de Inseto
2.
Cell ; 184(16): 4329-4347.e23, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34237253

RESUMO

We have produced gene expression profiles of all 302 neurons of the C. elegans nervous system that match the single-cell resolution of its anatomy and wiring diagram. Our results suggest that individual neuron classes can be solely identified by combinatorial expression of specific gene families. For example, each neuron class expresses distinct codes of ∼23 neuropeptide genes and ∼36 neuropeptide receptors, delineating a complex and expansive "wireless" signaling network. To demonstrate the utility of this comprehensive gene expression catalog, we used computational approaches to (1) identify cis-regulatory elements for neuron-specific gene expression and (2) reveal adhesion proteins with potential roles in process placement and synaptic specificity. Our expression data are available at https://cengen.org and can be interrogated at the web application CengenApp. We expect that this neuron-specific directory of gene expression will spur investigations of underlying mechanisms that define anatomy, connectivity, and function throughout the C. elegans nervous system.


Assuntos
Caenorhabditis elegans/metabolismo , Sistema Nervoso/metabolismo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Corantes Fluorescentes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Larva/metabolismo , Neurônios/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Motivos de Nucleotídeos/genética , RNA-Seq , Sequências Reguladoras de Ácido Nucleico/genética , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
3.
Nature ; 615(7950): 158-167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36634707

RESUMO

Despite the success of PD-1 blockade in melanoma and other cancers, effective treatment strategies to overcome resistance to cancer immunotherapy are lacking1,2. Here we identify the innate immune kinase TANK-binding kinase 1 (TBK1)3 as a candidate immune-evasion gene in a pooled genetic screen4. Using a suite of genetic and pharmacological tools across multiple experimental model systems, we confirm a role for TBK1 as an immune-evasion gene. Targeting TBK1 enhances responses to PD-1 blockade by decreasing the cytotoxicity threshold to effector cytokines (TNF and IFNγ). TBK1 inhibition in combination with PD-1 blockade also demonstrated efficacy using patient-derived tumour models, with concordant findings in matched patient-derived organotypic tumour spheroids and matched patient-derived organoids. Tumour cells lacking TBK1 are primed to undergo RIPK- and caspase-dependent cell death in response to TNF and IFNγ in a JAK-STAT-dependent manner. Taken together, our results demonstrate that targeting TBK1 is an effective strategy to overcome resistance to cancer immunotherapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Evasão da Resposta Imune , Imunoterapia , Proteínas Serina-Treonina Quinases , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Imunoterapia/métodos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Organoides , Fatores de Necrose Tumoral/imunologia , Interferon gama/imunologia , Esferoides Celulares , Caspases , Janus Quinases , Fatores de Transcrição STAT
4.
Nature ; 586(7828): 207-216, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33028997

RESUMO

The growing maturity of integrated photonic technology makes it possible to build increasingly large and complex photonic circuits on the surface of a chip. Today, most of these circuits are designed for a specific application, but the increase in complexity has introduced a generation of photonic circuits that can be programmed using software for a wide variety of functions through a mesh of on-chip waveguides, tunable beam couplers and optical phase shifters. Here we discuss the state of this emerging technology, including recent developments in photonic building blocks and circuit architectures, as well as electronic control and programming strategies. We cover possible applications in linear matrix operations, quantum information processing and microwave photonics, and examine how these generic chips can accelerate the development of future photonic circuits by providing a higher-level platform for prototyping novel optical functionalities without the need for custom chip fabrication.

5.
Nature ; 588(7836): 39-47, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33268862

RESUMO

Artificial intelligence tasks across numerous applications require accelerators for fast and low-power execution. Optical computing systems may be able to meet these domain-specific needs but, despite half a century of research, general-purpose optical computing systems have yet to mature into a practical technology. Artificial intelligence inference, however, especially for visual computing applications, may offer opportunities for inference based on optical and photonic systems. In this Perspective, we review recent work on optical computing for artificial intelligence applications and discuss its promise and challenges.

6.
Proc Natl Acad Sci U S A ; 120(28): e2221961120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399376

RESUMO

Changes in phenology in response to ongoing climate change have been observed in numerous taxa around the world. Differing rates of phenological shifts across trophic levels have led to concerns that ecological interactions may become increasingly decoupled in time, with potential negative consequences for populations. Despite widespread evidence of phenological change and a broad body of supporting theory, large-scale multitaxa evidence for demographic consequences of phenological asynchrony remains elusive. Using data from a continental-scale bird-banding program, we assess the impact of phenological dynamics on avian breeding productivity in 41 species of migratory and resident North American birds breeding in and around forested areas. We find strong evidence for a phenological optimum where breeding productivity decreases in years with both particularly early or late phenology and when breeding occurs early or late relative to local vegetation phenology. Moreover, we demonstrate that landbird breeding phenology did not keep pace with shifts in the timing of vegetation green-up over a recent 18-y period, even though avian breeding phenology has tracked green-up with greater sensitivity than arrival for migratory species. Species whose breeding phenology more closely tracked green-up tend to migrate shorter distances (or are resident over the entire year) and breed earlier in the season. These results showcase the broadest-scale evidence yet of the demographic impacts of phenological change. Future climate change-associated phenological shifts will likely result in a decrease in breeding productivity for most species, given that bird breeding phenology is failing to keep pace with climate change.


Assuntos
Aves Canoras , Animais , Mudança Climática , Estações do Ano , América do Norte , Demografia
7.
Proc Natl Acad Sci U S A ; 120(34): e2209735120, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579162

RESUMO

The hydroxyl radical (OH) fuels atmospheric chemical cycling as the main sink for methane and a driver of the formation and loss of many air pollutants, but direct OH observations are sparse. We develop and evaluate an observation-based proxy for short-term, spatial variations in OH (ProxyOH) in the remote marine troposphere using comprehensive measurements from the NASA Atmospheric Tomography (ATom) airborne campaign. ProxyOH is a reduced form of the OH steady-state equation representing the dominant OH production and loss pathways in the remote marine troposphere, according to box model simulations of OH constrained with ATom observations. ProxyOH comprises only eight variables that are generally observed by routine ground- or satellite-based instruments. ProxyOH scales linearly with in situ [OH] spatial variations along the ATom flight tracks (median r2 = 0.90, interquartile range = 0.80 to 0.94 across 2-km altitude by 20° latitudinal regions). We deconstruct spatial variations in ProxyOH as a first-order approximation of the sensitivity of OH variations to individual terms. Two terms modulate within-region ProxyOH variations-water vapor (H2O) and, to a lesser extent, nitric oxide (NO). This implies that a limited set of observations could offer an avenue for observation-based mapping of OH spatial variations over much of the remote marine troposphere. Both H2O and NO are expected to change with climate, while NO also varies strongly with human activities. We also illustrate the utility of ProxyOH as a process-based approach for evaluating intermodel differences in remote marine tropospheric OH.

8.
Annu Rev Genomics Hum Genet ; 23: 331-361, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36044908

RESUMO

A mosaic state arises when pathogenic variants are acquired in certain cell lineages during postzygotic development, and mosaic individuals may present with a generalized or localized phenotype. Here, we review the current state of knowledge regarding mosaicism for eight common tumor suppressor genes-NF1, NF2, TSC1, TSC2, PTEN, VHL, RB1, and TP53-and their related genetic syndromes/entities. We compare and discuss approaches for comprehensive diagnostic genetic testing, the spectrum of variant allele frequency, and disease severity. We also review affected individuals who have no mutation identified after conventional genetic analysis, as well as genotype-phenotype correlations and transmission risk for each tumor suppressor gene in full heterozygous and mosaic patients. This review provides new insight into similarities as well as marked differences regarding the appreciation of mosaicism in these tumor suppressor syndromes.


Assuntos
Genes Supressores de Tumor , Mosaicismo , Humanos , Mutação , Fenótipo , Prevalência
9.
N Engl J Med ; 386(5): 437-448, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35045221

RESUMO

BACKGROUND: Standard therapy for advanced endometrial cancer after failure of platinum-based chemotherapy remains unclear. METHODS: In this phase 3 trial, we randomly assigned, in a 1:1 ratio, patients with advanced endometrial cancer who had previously received at least one platinum-based chemotherapy regimen to receive either lenvatinib (20 mg, administered orally once daily) plus pembrolizumab (200 mg, administered intravenously every 3 weeks) or chemotherapy of the treating physician's choice (doxorubicin at 60 mg per square meter of body-surface area, administered intravenously every 3 weeks, or paclitaxel at 80 mg per square meter, administered intravenously weekly [with a cycle of 3 weeks on and 1 week off]). The two primary end points were progression-free survival as assessed on blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1, and overall survival. The end points were evaluated in patients with mismatch repair-proficient (pMMR) disease and in all patients. Safety was also assessed. RESULTS: A total of 827 patients (697 with pMMR disease and 130 with mismatch repair-deficient disease) were randomly assigned to receive lenvatinib plus pembrolizumab (411 patients) or chemotherapy (416 patients). The median progression-free survival was longer with lenvatinib plus pembrolizumab than with chemotherapy (pMMR population: 6.6 vs. 3.8 months; hazard ratio for progression or death, 0.60; 95% confidence interval [CI], 0.50 to 0.72; P<0.001; overall: 7.2 vs. 3.8 months; hazard ratio, 0.56; 95% CI, 0.47 to 0.66; P<0.001). The median overall survival was longer with lenvatinib plus pembrolizumab than with chemotherapy (pMMR population: 17.4 vs. 12.0 months; hazard ratio for death, 0.68; 95% CI, 0.56 to 0.84; P<0.001; overall: 18.3 vs. 11.4 months; hazard ratio, 0.62; 95% CI, 0.51 to 0.75; P<0.001). Adverse events of grade 3 or higher occurred in 88.9% of the patients who received lenvatinib plus pembrolizumab and in 72.7% of those who received chemotherapy. CONCLUSIONS: Lenvatinib plus pembrolizumab led to significantly longer progression-free survival and overall survival than chemotherapy among patients with advanced endometrial cancer. (Funded by Eisai and Merck Sharp and Dohme [a subsidiary of Merck]; Study 309-KEYNOTE-775 ClinicalTrials.gov number, NCT03517449.).


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Quinolinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Quinolinas/efeitos adversos , Análise de Sobrevida
10.
N Engl J Med ; 387(17): 1557-1568, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36094839

RESUMO

BACKGROUND: In a pilot study involving patients with cutaneous squamous-cell carcinoma, a high percentage of patients had a pathological complete response with the use of two doses of neoadjuvant cemiplimab before surgery. Data from a phase 2 study are needed to confirm these findings. METHODS: We conducted a phase 2, confirmatory, multicenter, nonrandomized study to evaluate cemiplimab as neoadjuvant therapy in patients with resectable stage II, III, or IV (M0) cutaneous squamous-cell carcinoma. Patients received cemiplimab, administered at a dose of 350 mg every 3 weeks for up to four doses, before undergoing surgery with curative intent. The primary end point was a pathological complete response (the absence of viable tumor cells in the surgical specimen) on independent review at a central laboratory, with a null hypothesis that a pathological complete response would be observed in 25% of patients. Key secondary end points included a pathological major response (the presence of viable tumor cells that constitute ≤10% of the surgical specimen) on independent review, a pathological complete response and a pathological major response on investigator assessment at a local laboratory, an objective response on imaging, and adverse events. RESULTS: A total of 79 patients were enrolled and received neoadjuvant cemiplimab. On independent review, a pathological complete response was observed in 40 patients (51%; 95% confidence interval [CI], 39 to 62) and a pathological major response in 10 patients (13%; 95% CI, 6 to 22). These results were consistent with the pathological responses determined on investigator assessment. An objective response on imaging was observed in 54 patients (68%; 95% CI, 57 to 78). Adverse events of any grade that occurred during the study period, regardless of whether they were attributed to the study treatment, were observed in 69 patients (87%). Grade 3 or higher adverse events that occurred during the study period were observed in 14 patients (18%). CONCLUSIONS: Neoadjuvant therapy with cemiplimab was associated with a pathological complete response in a high percentage of patients with resectable cutaneous squamous-cell carcinoma. (Funded by Regeneron Pharmaceuticals and Sanofi; ClinicalTrials.gov number, NCT04154943.).


Assuntos
Carcinoma de Células Escamosas , Terapia Neoadjuvante , Neoplasias Cutâneas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Estadiamento de Neoplasias , Projetos Piloto , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Indução de Remissão , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico
11.
Proc Natl Acad Sci U S A ; 119(37): e2201213119, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36067322

RESUMO

Atmospheric electrical discharges are now known to generate unexpectedly large amounts of the atmosphere's primary oxidant, hydroxyl (OH), in thunderstorm anvils, where electrical discharges are caused by atmospheric charge separation. The question is "Do other electrical discharges also generate large amounts of oxidants?" In this paper, we demonstrate that corona formed on grounded metal objects under thunderstorms produce extreme amounts of OH, hydroperoxyl (HO2), and ozone (O3). Hundreds of parts per trillion to parts per billion of OH and HO2 were measured during seven thunderstorms that passed over the rooftop site during an air quality study in Houston, TX in summer 2006. A combination of analysis of these field results and laboratory experiments shows that these extreme oxidant amounts were generated by corona on the inlet of the OH-measuring instrument and that corona are easier to generate on lightning rods than on the inlet. In the laboratory, increasing the electric field increased OH, HO2, and O3, with 14 times more O3 generated than OH and HO2, which were equal. Calculations show that corona on lightning rods can annually generate OH that is 10-100 times ambient amounts within centimeters of the lightning rod and on high-voltage electrical power lines can generate OH that is 500 times ambient a meter away from the corona. Contrary to current thinking, previously unrecognized corona-generated OH, not corona-generated UV radiation, mostly likely initiates premature degradation of high-voltage polymer insulators.

12.
Proc Natl Acad Sci U S A ; 119(48): e2206829119, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36409915

RESUMO

Retinal ganglion cells (RGCs) are heterogeneous projection neurons that convey distinct visual features from the retina to brain. Here, we present a high-throughput in vivo RGC activity assay in response to light stimulation using noninvasive Ca2+ imaging of thousands of RGCs simultaneously in living mice. Population and single-cell analyses of longitudinal RGC Ca2+ imaging reveal distinct functional responses of RGCs and unprecedented individual RGC activity conversions during traumatic and glaucomatous degeneration. This study establishes a foundation for future in vivo RGC function classifications and longitudinal activity evaluations using more advanced imaging techniques and visual stimuli under normal, disease, and neural repair conditions. These analyses can be performed at both the population and single-cell levels using temporal and spatial information, which will be invaluable for understanding RGC pathophysiology and identifying functional biomarkers for diverse optic neuropathies.


Assuntos
Glaucoma , Células Ganglionares da Retina , Animais , Camundongos , Diagnóstico por Imagem , Retina , Glaucoma/diagnóstico por imagem , Encéfalo
13.
Emerg Infect Dis ; 30(13): S17-S20, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38561633

RESUMO

The large COVID-19 outbreaks in prisons in the Washington (USA) State Department of Corrections (WADOC) system during 2020 highlighted the need for a new public health approach to prevent and control COVID-19 transmission in the system's 12 facilities. WADOC and the Washington State Department of Health (WADOH) responded by strengthening partnerships through dedicated corrections-focused public health staff, improving cross-agency outbreak response coordination, implementing and developing corrections-specific public health guidance, and establishing collaborative data systems. The preexisting partnerships and trust between WADOC and WADOH, strengthened during the COVID-19 response, laid the foundation for a collaborative response during late 2021 to the largest tuberculosis outbreak in Washington State in the past 20 years. We describe challenges of a multiagency collaboration during 2 outbreak responses, as well as approaches to address those challenges, and share lessons learned for future communicable disease outbreak responses in correctional settings.


Assuntos
COVID-19 , Tuberculose , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Saúde Pública , Prisões , Washington/epidemiologia , Pandemias/prevenção & controle , Surtos de Doenças/prevenção & controle , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
14.
Cancer ; 130(15): 2670-2682, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38696121

RESUMO

BACKGROUND: Merkel cell carcinoma (MCC) is an aggressive cancer with often poor outcomes. Limited biomarkers exist for predicting clinical outcomes. The Merkel cell polyomavirus (MCPyV) serum antibody test (AMERK) has shown potential for indicating better recurrence-free survival in a single-institution study. The study aimed to evaluate the link between initial AMERK serostatus and survival. Secondary objectives included examining the relationship between initial AMERK titer levels and tumor burden. METHODS: A retrospective cohort study across two institutions analyzed patients tested with AMERK within 90 days of MCC diagnosis. Regression models assessed the association of survival outcomes with serostatus, considering various factors. The relationship between AMERK titer and tumor burden indicators was evaluated using ANOVA. Significance testing was exploratory, without a fixed significance level. RESULTS: Of 261 MCC patients tested, 49.4% were initially seropositive (titer ≥75). Multivariable analysis showed that seropositivity improved recurrence, event-free, overall, and MCC-specific survival rates. Strong associations were found between initial AMERK titer and clinical, tumor, and nodal stages, tumor size, and disease extent. Notably, improved survival with seropositivity was observed only in patients with localized disease at initial presentation. CONCLUSION: Circulating antibodies to MCPyV oncoproteins, as indicated by the AMERK test, are linked with better survival in MCC patients with localized disease at presentation. This could enhance patient risk profiling and treatment personalization. The study's retrospective nature and exploratory analysis are key limitations. PLAIN LANGUAGE SUMMARY: Merkel cell carcinoma (MCC) is a potentially aggressive skin cancer, and tools to predict patient outcomes are limited. A blood test called anti-Merkel cell panel (AMERK), which checks for specific antibodies related to this cancer, might give us some clues. In this study, we looked at 261 MCC patients who took the AMERK test within 90 days of diagnosis. We found that patients with an initial positive AMERK result tended to have better outcomes, especially if their cancer was in the early stages. However, it is important to note that this study has limitations, including using retrospective data and exploratory analyses.


Assuntos
Anticorpos Antivirais , Carcinoma de Célula de Merkel , Poliomavírus das Células de Merkel , Neoplasias Cutâneas , Humanos , Carcinoma de Célula de Merkel/virologia , Carcinoma de Célula de Merkel/sangue , Carcinoma de Célula de Merkel/mortalidade , Carcinoma de Célula de Merkel/diagnóstico , Carcinoma de Célula de Merkel/imunologia , Poliomavírus das Células de Merkel/imunologia , Poliomavírus das Células de Merkel/isolamento & purificação , Feminino , Masculino , Estudos Retrospectivos , Idoso , Prognóstico , Pessoa de Meia-Idade , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/virologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Anticorpos Antivirais/sangue , Idoso de 80 Anos ou mais , Infecções Tumorais por Vírus/virologia , Infecções por Polyomavirus/sangue , Infecções por Polyomavirus/diagnóstico , Infecções por Polyomavirus/virologia , Infecções por Polyomavirus/imunologia
15.
Environ Microbiol ; 26(9): e16690, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39228053

RESUMO

Sponge microbiomes are often highly diverse making it difficult to determine which lineages are important for maintaining host health and homeostasis. Characterising genomic traits associated with symbiosis can improve our knowledge of which lineages have adapted to their host and what functions they might provide. Here we examined five microbial families associated with sponges that have previously shown evidence of cophylogeny, including Endozoicomonadaceae, Nitrosopumilaceae, Spirochaetaceae, Microtrichaceae and Thermoanaerobaculaceae, to better understand the mechanisms behind their symbiosis. We compared sponge-associated genomes to genomes found in other environments and found that sponge-specific clades were enriched in genes encoding many known mechanisms for symbiont survival, such as avoiding phagocytosis and defence against foreign genetic elements. We expand on previous knowledge to show that glycosyl hydrolases with sulfatases and sulfotransferases likely form multienzyme degradation pathways to break and remodel sulfated polysaccharides and reveal an enrichment in superoxide dismutase that may prevent damage from free oxygen radicals produced by the host. Finally, we identified novel traits in sponge-associated symbionts, such as urea metabolism in Spirochaetaceae which was previously shown to be rare in the phylum Spirochaetota. These results identify putative mechanisms by which symbionts have adapted to living in association with sponges.


Assuntos
Bactérias , Genômica , Poríferos , Simbiose , Poríferos/microbiologia , Animais , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Microbiota , Filogenia , Genoma Bacteriano
16.
Chembiochem ; : e202400290, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39031755

RESUMO

The high-fidelity sesquiterpene cyclase (-)-germacradien-4-ol synthase (GdolS) converts farnesyl diphosphate into the macrocyclic alcohol (-)-germacradien-4-ol. Site-directed mutagenesis was used to decipher the role of key residues in the water control mechanism. Replacement of Ala176, located in the G1/2 helix, with non-polar aliphatic residues of increasing size (valine, leucine, isoleucine and methionine) resulted in the accumulation of the non-hydroxylated products germacrene A and germacrene D. In contrast, hydroxylation was maintained when the polar residues threonine, glutamine or aspartate replaced Ala176. Additionally, although a contribution of His150 to the nucleophilic water addition could be ruled out, the imidazole ring of His150 appears to assist carbocation stabilisation. The results presented here shed light on how hydroxylating sesquiterpene synthases can be engineered to design modified sesquiterpene synthases to reduce the need for further steps in the biocatalytic production of oxygenated sesquiterpenoids.

17.
Pharmacogenomics J ; 24(4): 19, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890281

RESUMO

Nimodipine, an L-type cerebroselective calcium channel antagonist, is the only drug approved by the US Food and Drug Administration for the neuroprotection of patients with aneurysmal subarachnoid hemorrhage (aSAH). Four randomized, placebo-controlled trials of nimodipine demonstrated clinical improvement over placebo; however, these occurred before precision medicine with pharmacogenomics was readily available. The standard enteral dose of nimodipine recommended after aSAH is 60 mg every 4 h. However, up to 78% of patients with aSAH develop systemic arterial hypotension after taking the drug at the recommended dose, which could theoretically limit its neuroprotective role and worsen cerebral perfusion pressure and cerebral blood flow, particularly when concomitant vasospasm is present. We investigated the association between nimodipine dose changes and clinical outcomes in a consecutive series of 150 patients (mean age, 56 years; 70.7% women) with acute aSAH. We describe the pharmacogenomic relationship of nimodipine dose reduction with clinical outcomes. These results have major implications for future individualized dosing of nimodipine in the era of precision medicine.


Assuntos
Bloqueadores dos Canais de Cálcio , Nimodipina , Farmacogenética , Hemorragia Subaracnóidea , Humanos , Nimodipina/administração & dosagem , Nimodipina/efeitos adversos , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/genética , Hemorragia Subaracnóidea/complicações , Pessoa de Meia-Idade , Feminino , Masculino , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/efeitos adversos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Idoso , Farmacogenética/métodos , Resultado do Tratamento , Relação Dose-Resposta a Droga , Adulto , Medicina de Precisão/métodos , Vasoespasmo Intracraniano/tratamento farmacológico
18.
Mol Ecol ; 33(16): e17468, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39046252

RESUMO

The future survival of coral reefs in the Anthropocene depends on the capacity of corals to adapt as oceans warm and extreme weather events become more frequent. Targeted interventions designed to assist evolutionary processes in corals require a comprehensive understanding of the distribution and structure of standing variation, however, efforts to map genomic variation in corals have so far focussed almost exclusively on SNPs, overlooking structural variants that have been shown to drive adaptive processes in other taxa. Here, we show that the reef-building coral, Acropora kenti, harbours at least five large, highly polymorphic structural variants, all of which exhibit signatures of strongly suppressed recombination in heterokaryotypes, a feature commonly associated with chromosomal inversions. Based on their high minor allele frequency, uniform distribution across habitats and elevated genetic load, we propose that these inversions in A. kenti are likely to be under balancing selection. An excess of SNPs with high impact on protein-coding genes within these loci elevates their importance both as potential targets for adaptive selection and as contributors to genetic decline if coral populations become fragmented or inbred in future.


Assuntos
Antozoários , Inversão Cromossômica , Recifes de Corais , Polimorfismo de Nucleotídeo Único , Antozoários/genética , Inversão Cromossômica/genética , Animais , Polimorfismo de Nucleotídeo Único/genética , Seleção Genética , Frequência do Gene , Carga Genética , Mutação , Genética Populacional
19.
Opt Express ; 32(12): 21092-21101, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859472

RESUMO

Endoscopic angle-resolved light scattering methods have been developed for early cancer detection but they typically require multi-element coherent fiber optic bundles to recover scattering distributions from tissues. Recent work has focused on using a single multimode fiber (MMF) to measure angle resolved scattering but this approach has practical limitations to overcome before clinical translation. Here we address these limitations by proposing an MMF-based endoscope capable of measuring angular scattering patterns suitable for determining structure. Significantly, this approach implements a spectrally resolved detection scheme to reduce speckle and leverages the azimuthal symmetry of the angular scattering patterns to enable measurements that are robust to fiber bending. This results in a unique method that does not require matrix inversion or machine learning to measure a transmitted scattering distribution. The MMF utilized here is 1000 mm in length with a 200 µm core and is demonstrated to recover angular scattering distributions even with bending displacements of up to 30 cm. This advance has a significant impact on the clinical translation of biomedical endoscopic diagnostic techniques that use angular scattering to determine the size of cell nuclei to detect early cancer.

20.
Opt Lett ; 49(15): 4457-4460, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090958

RESUMO

We demonstrate the use of a novel, to the best of our knowledge, localization algorithm for digitally refocusing fluorescence images from a three-dimensional cell culture. Simultaneous phase and fluorescence intensity images are collected through a multimodal system that combines digital holography via quantitative phase microscopy (QPM) and fluorescence microscopy. Defocused fluorescence images are localized to a specific z-plane within the three-dimensional (3D) matrix using the transport of intensity equation (TIE) and depth-resolved information derived from the QPM measurements. This technique is applied to cells stained with different fluorescent tags suspended in 3D collagen hydrogel cultures. Experimental findings demonstrate the localization of defocused images, facilitating the analysis and comparison of cells within the hydrogel matrix. This method holds promise for comprehensive cellular imaging of fluorescence labeling in three-dimensional environments, enabling detailed investigations into cellular behavior and interactions.

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