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1.
Immunity ; 55(10): 1940-1952.e5, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36223726

RESUMO

T cells mediate antigen-specific immune responses to disease through the specificity and diversity of their clonotypic T cell receptors (TCRs). Determining the spatial distributions of T cell clonotypes in tissues is essential to understanding T cell behavior, but spatial sequencing methods remain unable to profile the TCR repertoire. Here, we developed Slide-TCR-seq, a 10-µm-resolution method, to sequence whole transcriptomes and TCRs within intact tissues. We confirmed the ability of Slide-TCR-seq to map the characteristic locations of T cells and their receptors in mouse spleen. In human lymphoid germinal centers, we identified spatially distinct TCR repertoires. Profiling T cells in renal cell carcinoma and melanoma specimens revealed heterogeneous immune responses: T cell states and infiltration differed intra- and inter-clonally, and adjacent tumor and immune cells exhibited distinct gene expression. Altogether, our method yields insights into the spatial relationships between clonality, neighboring cell types, and gene expression that drive T cell responses.


Assuntos
Receptores de Antígenos de Linfócitos T , Transcriptoma , Imunidade Adaptativa/genética , Animais , Humanos , Camundongos , Linfócitos T
2.
Nature ; 605(7910): 532-538, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35508657

RESUMO

Within the tumour microenvironment, CD4+ T cells can promote or suppress antitumour responses through the recognition of antigens presented by human leukocyte antigen (HLA) class II molecules1,2, but how cancers co-opt these physiologic processes to achieve immune evasion remains incompletely understood. Here we performed in-depth analysis of the phenotype and tumour specificity of CD4+ T cells infiltrating human melanoma specimens, finding that exhausted cytotoxic CD4+ T cells could be directly induced by melanoma cells through recognition of HLA class II-restricted neoantigens, and also HLA class I-restricted tumour-associated antigens. CD4+ T regulatory (TReg) cells could be indirectly elicited through presentation of tumour antigens via antigen-presenting cells. Notably, numerous tumour-reactive CD4+ TReg clones were stimulated directly by HLA class II-positive melanoma and demonstrated specificity for melanoma neoantigens. This phenomenon was observed in the presence of an extremely high tumour neoantigen load, which we confirmed to be associated with HLA class II positivity through the analysis of 116 melanoma specimens. Our data reveal the landscape of infiltrating CD4+ T cells in melanoma and point to the presentation of HLA class II-restricted neoantigens and direct engagement of immunosuppressive CD4+ TReg cells as a mechanism of immune evasion that is favoured in HLA class II-positive melanoma.


Assuntos
Antígenos de Neoplasias , Linfócitos T CD4-Positivos , Melanoma , Neoplasias Cutâneas , Células Apresentadoras de Antígenos , Antígenos de Neoplasias/imunologia , Antígenos HLA , Humanos , Melanoma/imunologia , Fenótipo , Neoplasias Cutâneas/imunologia , Células Tumorais Cultivadas , Microambiente Tumoral
3.
Plant Cell ; 34(11): 4232-4254, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36047828

RESUMO

Maternal-to-filial nutrition transfer is central to grain development and yield. nitrate transporter 1/peptide transporter (NRT1-PTR)-type transporters typically transport nitrate, peptides, and ions. Here, we report the identification of a maize (Zea mays) NRT1-PTR-type transporter that transports sucrose and glucose. The activity of this sugar transporter, named Sucrose and Glucose Carrier 1 (SUGCAR1), was systematically verified by tracer-labeled sugar uptake and serial electrophysiological studies including two-electrode voltage-clamp, non-invasive microelectrode ion flux estimation assays in Xenopus laevis oocytes and patch clamping in HEK293T cells. ZmSUGCAR1 is specifically expressed in the basal endosperm transfer layer and loss-of-function mutation of ZmSUGCAR1 caused significantly decreased sucrose and glucose contents and subsequent shrinkage of maize kernels. Notably, the ZmSUGCAR1 orthologs SbSUGCAR1 (from Sorghum bicolor) and TaSUGCAR1 (from Triticum aestivum) displayed similar sugar transport activities in oocytes, supporting the functional conservation of SUGCAR1 in closely related cereal species. Thus, the discovery of ZmSUGCAR1 uncovers a type of sugar transporter essential for grain development and opens potential avenues for genetic improvement of seed-filling and yield in maize and other grain crops.


Assuntos
Grão Comestível , Glucose , Transportadores de Nitrato , Transportador 1 de Peptídeos , Proteínas de Plantas , Sacarose , Zea mays , Humanos , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Glucose/metabolismo , Células HEK293 , Transportadores de Nitrato/genética , Transportadores de Nitrato/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sacarose/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Transportador 1 de Peptídeos/genética , Transportador 1 de Peptídeos/metabolismo , Transporte Biológico
4.
Oncologist ; 29(4): 324-331, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37950901

RESUMO

BACKGROUND: Nivolumab plus ipilimumab has demonstrated improved survival for treatment-naïve advanced clear cell renal cell carcinoma (RCC). A series of clinical trials evaluated the effect of salvage nivolumab plus ipilimumab in patients without an objective response to nivolumab. Given the size and heterogeneity of these studies, we performed a pooled analysis to better inform the activity of nivolumab plus ipilimumab after nivolumab. PATIENTS AND METHODS: Eligible patients included those with advanced clear cell RCC having received no prior immunotherapy. The primary objective was confirmed objective response rate (ORR) by investigator-assessment. Secondary objectives included progression-free survival (PFS) and overall survival (OS). RESULTS: The analysis included 410 patients with clear cell RCC, of whom 340 (82.9%) had IMDC intermediate/poor risk disease, and 137 (33.4%) had prior treatment. The 16-18-week ORR to nivolumab prior to nivolumab plus ipilimumab was 22.7% (n = 93), and best ORR to nivolumab was 25.1% (n = 103). Two hundred and thirty (56.1%) patients treated with nivolumab received nivolumab plus ipilimumab at a median of 16 weeks (IQR 9-19) after initiation of nivolumab [27.0% (n = 62) with stable disease and 73.0% (n = 168) with progressive disease to nivolumab]. The ORR to nivolumab plus ipilimumab was 12.6% (n = 29). Six-month PFS on nivolumab plus ipilimumab was 37% (95% CI, 27-47). Median follow-up was 34.3 months and 3-year OS was 59% (95% CI, 53-64) from nivolumab start. CONCLUSION: A small subset of patients lacking a response to nivolumab derive benefit from salvage nivolumab plus ipilimumab. When possible, both drugs should be given in concomitantly, rather in an adaptive fashion.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Nivolumabe/farmacologia , Nivolumabe/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Ipilimumab/efeitos adversos , Intervalo Livre de Progressão , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Ensaios Clínicos Fase II como Assunto
5.
Cancer Immunol Immunother ; 73(10): 192, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105820

RESUMO

PURPOSE: Immune checkpoint inhibitors have revolutionized the treatment of renal cell carcinoma (RCC), but many patients do not respond to therapy and the majority develop resistant disease over time. Thus, there is increasing need for alternative immunomodulating agents. The co-inhibitory molecule T-cell immunoglobulin and ITIM domain (TIGIT) may play a role in resistance to approved immune checkpoint inhibitors and is being investigated as a potential therapeutic target. The purpose of this study was to quantify TIGIT positivity in tumor-infiltrating T cells in RCC. METHODS: We employed tissue microarrays containing specimens from primary RCC tumors, adjacent normal renal tissue, and RCC metastases to quantify TIGIT within tumor-infiltrating CD3+ T cells using quantitative immunofluorescent analysis. We also compared these results to TIGIT+ CD3+ levels in four other tumor types (melanoma, non-small cell lung, cervical, and head and neck cancers). RESULTS: We did not observe significant differences in TIGIT positivity between primary RCC tumors and patient-matched metastatic samples. We found that the degree of TIGIT positivity in RCC is comparable to that in lung cancer but lower than that in melanoma, cervical, and head and neck cancers. Correlation analysis comparing TIGIT positivity to previously published, patient-matched spatial proteomic data by our group revealed a negative association between TIGIT and the checkpoint proteins PD-1 and LAG3. CONCLUSION: Our findings support careful evaluation of TIGIT expression on T cells in primary or metastatic RCC specimens for patients who may be treated with TIGIT-targeting antibodies, as increased TIGIT positivity might be associated with a greater likelihood of response to therapy.


Assuntos
Antígenos CD , Carcinoma de Células Renais , Neoplasias Renais , Proteína do Gene 3 de Ativação de Linfócitos , Linfócitos do Interstício Tumoral , Receptor de Morte Celular Programada 1 , Receptores Imunológicos , Humanos , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Receptores Imunológicos/metabolismo , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Antígenos CD/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Feminino , Masculino , Biomarcadores Tumorais/metabolismo
6.
Plant Cell ; 33(10): 3348-3366, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34323976

RESUMO

Carbohydrate partitioning from leaves to sink tissues is essential for plant growth and development. The maize (Zea mays) recessive carbohydrate partitioning defective28 (cpd28) and cpd47 mutants exhibit leaf chlorosis and accumulation of starch and soluble sugars. Transport studies with 14C-sucrose (Suc) found drastically decreased export from mature leaves in cpd28 and cpd47 mutants relative to wild-type siblings. Consistent with decreased Suc export, cpd28 mutants exhibited decreased phloem pressure in mature leaves, and altered phloem cell wall ultrastructure in immature and mature leaves. We identified the causative mutations in the Brittle Stalk2-Like3 (Bk2L3) gene, a member of the COBRA family, which is involved in cell wall development across angiosperms. None of the previously characterized COBRA genes are reported to affect carbohydrate export. Consistent with other characterized COBRA members, the BK2L3 protein localized to the plasma membrane, and the mutants condition a dwarf phenotype in dark-grown shoots and primary roots, as well as the loss of anisotropic cell elongation in the root elongation zone. Likewise, both mutants exhibit a significant cellulose deficiency in mature leaves. Therefore, Bk2L3 functions in tissue growth and cell wall development, and this work elucidates a unique connection between cellulose deposition in the phloem and whole-plant carbohydrate partitioning.


Assuntos
Metabolismo dos Carboidratos , Parede Celular/metabolismo , Proteínas de Plantas/genética , Zea mays/genética , Proteínas de Plantas/metabolismo , Zea mays/metabolismo
7.
J Hum Evol ; 190: 103498, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581918

RESUMO

The Homa Peninsula, in southwestern Kenya, continues to yield insights into Oldowan hominin landscape behaviors. The Late Pliocene locality of Nyayanga (∼3-2.6 Ma) preserves some of the oldest Oldowan tools. At the Early Pleistocene locality of Kanjera South (∼2 Ma) toolmakers procured a diversity of raw materials from over 10 km away and strategically reduced them in a grassland-dominated ecosystem. Here, we report findings from Sare-Abururu, a younger (∼1.7 Ma) Oldowan locality approximately 12 km southeast of Kanjera South and 18 km east of Nyayanga. Sare-Abururu has yielded 1754 artifacts in relatively undisturbed low-energy silts and sands. Stable isotopic analysis of pedogenic carbonates suggests that hominin activities were carried out in a grassland-dominated setting with similar vegetation structure as documented at Kanjera South. The composition of a nearby paleo-conglomerate indicates that high-quality stone raw materials were locally abundant. Toolmakers at Sare-Abururu produced angular fragments from quartz pebbles, representing a considerable contrast to the strategies used to reduce high quality raw materials at Kanjera South. Although lithic reduction at Sare-Abururu was technologically simple, toolmakers proficiently produced cutting edges, made few mistakes and exhibited a mastery of platform management, demonstrating that expedient technical strategies do not necessarily indicate a lack of skill or suitable raw materials. Lithic procurement and reduction patterns on the Homa Peninsula appear to reflect variation in local resource contexts rather than large-scale evolutionary changes in mobility, energy budget, or toolmaker cognition.


Assuntos
Hominidae , Animais , Quênia , Ecossistema , Evolução Biológica , Carbonatos , Arqueologia , Fósseis
8.
Mem Cognit ; 52(2): 417-429, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37798607

RESUMO

Deciding which task to perform when multiple tasks are available can be influenced by external influences in the environment. In the present study, we demonstrate that such external biases on task-choice behavior reflect reactive control adjustments instead of a failure in control to internally select a task goal. Specifically, in two experiments we delayed the onset of one of two task stimuli by a short (50 ms), medium (300 ms), or long (1,000 ms) stimulus-onset asynchrony (SOA) within blocks while also varying the relative frequencies of short versus long SOAs across blocks (i.e., short SOA frequent vs. long SOA frequent). Participants' task choices were increasingly biased towards selecting the task associated with the first stimulus with increasing SOAs. Critically, both experiments also revealed that the short-to-medium SOA bias was larger in blocks with more frequent long SOAs when participants had limited time to prepare for an upcoming trial. When time to select an upcoming task was extended in Experiment 2, this interaction was not significant, suggesting that the extent to which people rely on reactive control adjustments is additionally modulated by proactive control processes. Thus, the present findings also suggest that voluntary task choices are jointly guided by both proactive and reactive processes, which are likely to adjust the relative activation of different task goals in working memory.


Assuntos
Memória de Curto Prazo , Motivação , Humanos , Fatores de Tempo , Tempo de Reação/fisiologia , Comportamento de Escolha
9.
Am J Perinatol ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38569507

RESUMO

OBJECTIVE: Recent studies have reported associations between severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection during pregnancy and adverse perinatal outcomes but the extent to which these associations vary by race/ethnicity remains uncertain. Therefore, we examined how the association between prenatal SARS-CoV-2 infection and adverse perinatal outcomes may be modified by race/ethnicity. STUDY DESIGN: A retrospective cohort study was performed using data on 67,986 pregnant women extracted from the Kaiser Permanente Southern California electronic health records between April 6, 2020, and December 31, 2021. Upon admission to labor and delivery, all women were routinely tested for coronavirus disease 2019 (COVID-19) using real-time reverse-transcriptase polymerase chain reaction test. Adjusted odds ratios (aORs) were used to estimate associations. RESULTS: During the study period, COVID-19 was diagnosed in 4,960 (7%) of singleton pregnancies, with the highest rates observed among Hispanics (9.4%) and non-Hispanic Blacks (6.2%). Compared with non-Hispanic Whites, Hispanics (aOR: 1.12, 95% CI: 1.03, 1.21) with SARS-CoV-2 infection had the highest odds of a pregnancy associated with nonreassuring fetal heart rate tracing. Neonates of all races/ethnicities, except for non-Hispanic Blacks, showed significantly increased odds of SARS-CoV-2 infection, with the highest risk observed among Asians/Pacific Islanders (aOR: 10.88, 95% CI: 1.33, 89.04). Non-Hispanic White mothers who tested positive were admitted to intensive care unit (ICU) at a higher rate at delivery and within 7 days of delivery (aOR: 34.77, 95% CI: 11.3, 107.04; aOR: 26.48, 95% CI: 9.55, 73.46, respectively). Hispanics were also at a significantly higher odds of admission to ICU (aOR: 4.62, 95% CI: 2.69, 7.94; aOR: 4.42, 95% CI: 2.58, 7.56, respectively). Non-Hispanic Black, Hispanic, and Asian/Pacific Islander mothers who tested positive for SARS-CoV-2 prenatally, were at increased risk for preeclampsia/eclampsia, and preterm birth as compared to non-Hispanic White mothers. CONCLUSION: The findings highlight racial/ethnic disparities in the association between SARS-CoV-2 infection and adverse perinatal outcomes. The risk of neonatal SARS-CoV-2 infection was highest for Asian/Pacific Islanders. We also observed a remarkably high risk of ICU admission for non-Hispanic White mothers infected with SARS-CoV-2. KEY POINTS: · Race/ethnicity influences perinatal outcomes in pregnancies impacted by SARS-CoV-2.. · The risk of neonatal SARS-CoV-2 infection was highest for Asian/Pacific Islanders.. · White mothers had a notably high risk of ICU admission at delivery following SARS-CoV-2 infection..

10.
Ann Hum Biol ; 51(1): 2310724, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38594936

RESUMO

BACKGROUND: Pastoralists live in challenging environments, which may be accompanied by unique activity, energy, and water requirements. AIM: Few studies have examined whether the demands of pastoralism contribute to differences in total energy expenditure (TEE) and water turnover (WT) compared to other lifestyles. SUBJECTS AND METHODS: Accelerometer-derived physical activity, doubly labelled water-derived TEE and WT, and anthropometric data were collected for 34 semi-nomadic Daasanach adults from three northern Kenyan communities with different levels of pastoralist activity. Daasanach TEEs and WTs were compared to those of other small-scale and industrialised populations. RESULTS: When modelled as a function of fat-free-mass, fat-mass, age, and sex, TEE did not differ between Daasanach communities. Daasanach TEE (1564-4172 kcal/day) was not significantly correlated with activity and 91% of TEEs were within the range expected for individuals from comparison populations. Mean WT did not differ between Daasanach communities; Daasanach absolute (7.54 litres/day men; 7.46 litres/day women), mass-adjusted, and TEE-adjusted WT was higher than most populations worldwide. CONCLUSIONS: The similar mass-adjusted TEE of Daasanach and industrialised populations supports the hypothesis that habitual TEE is constrained, with physically demanding lifestyles necessitating trade-offs in energy allocation. Elevated WT in the absence of elevated TEE likely reflects a demanding active lifestyle in a hot, arid climate.


Assuntos
Metabolismo Energético , Água , Adulto , Masculino , Humanos , Feminino , Quênia , Exercício Físico , Antropometria
11.
J Pediatr ; 261: 113577, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37353144

RESUMO

OBJECTIVE: To study the association between discontinuing predischarge car seat tolerance screening (CSTS) with 30-day postdischarge adverse outcomes in infants born preterm. STUDY DESIGN: Retrospective cohort study involving all infants born preterm from 2010 through 2021 who survived to discharge to home in a 14-hospital integrated health care system. The exposure was discontinuation of CSTS. The primary outcome was a composite rate of death, 911 call-triggered transports, or readmissions associated with diagnostic codes of respiratory disorders, apnea, apparent life-threatening event, or brief resolved unexplained events within 30 days of discharge. Outcomes of infants born in the periods of CSTS and after discontinuation were compared. RESULTS: Twelve of 14 hospitals initially utilized CSTS and contributed patients to the CSTS period; 71.4% of neonatal intensive care unit (NICU) patients and 26.9% of non-NICU infants were screened. All hospitals participated in the discontinuation period; 0.1% was screened. Rates of the unadjusted primary outcome were 1.02% in infants in the CSTS period (n = 21 122) and 1.06% after discontinuation (n = 20 142) (P = .76). The aOR (95% CI) was 0.95 (0.75, 1.19). Statistically insignificant differences between periods were observed in components of the primary outcome, gestational age strata, NICU admission status groups, and other secondary analyses. CONCLUSIONS: Discontinuation of CSTS in a large integrated health care network was not associated with a change in 30-day postdischarge adverse outcomes. CSTS's value as a standard predischarge assessment deserves further evaluation.


Assuntos
Sistemas de Proteção para Crianças , Recém-Nascido Prematuro , Recém-Nascido , Humanos , Lactente , Sistemas de Proteção para Crianças/efeitos adversos , Alta do Paciente , Estudos Retrospectivos , Assistência ao Convalescente , Unidades de Terapia Intensiva Neonatal
12.
Bioconjug Chem ; 34(8): 1398-1406, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37534797

RESUMO

Small molecule fluorescent probes that bind selectively to plant cell wall polysaccharides have been instrumental in elucidating the localization and function of these glycans. Arabinogalactan proteins (AGPs) are cell wall proteoglycans implicated in essential functions such as cell signaling, plant growth, and programmed cell death. There is currently no small molecule probe capable of fluorescently labeling AGPs. The Yariv reagents are the only small molecules that bind AGPs, and have been used to study AGP function and isolate AGPs via precipitation of an AGP-Yariv complex. However, the Yariv reagents are not fluorescent, rendering them ineffective for localization studies using fluorescence microscopy. A fluorescent version of a Yariv reagent that is capable of both binding as well as imaging AGPs would provide a powerful tool for studying AGPs in planta. Herein, we describe the synthesis of an azido analog of the Yariv reagent that can be further functionalized with a fluorophore to provide a glycoconjugate that binds AGPs and is fluorescent. We show that the modified reagent binds gum arabic in in vitro binding assays when used in conjunction with the ßGlcYariv reagent. Fluorescent imaging of AGPs in fixed maize leaf tissue enables localization of AGPs to cell walls in the leaf. Significantly, imaging can also be carried out using fresh tissue. This represents the first small molecule probe that can be used to visualize AGPs using fluorescence microscopy.


Assuntos
Glucosídeos , Floroglucinol , Glucosídeos/metabolismo , Floroglucinol/metabolismo , Membrana Celular/metabolismo , Microscopia de Fluorescência
13.
J Hum Evol ; 183: 103427, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37734121

RESUMO

In the study of Early Pleistocene stone artifacts, researchers have made considerable progress in reconstructing the technical decisions of hominins by examining various aspects of lithic technology, such as reduction sequences, hammer selection, platform preparation, core management, and raw material selection. By comparison, our understanding of the ways in which Early Pleistocene hominins controlled the delivery and application of percussive force during flaking remains limited. In this study, we focus on a key aspect of force delivery in stone knapping, namely the hammerstone striking angle (or the angle of blow), which has been shown to play a significant role in determining the knapping outcome. Using a dataset consists of 12 Early Pleistocene flake assemblages dated from 1.95 Ma to 1.4 Ma, we examined temporal patterns of the hammer striking angle by quantifying the bulb angle, a property of the flake's Hertzian cone that reflects the hammer striking angle used in flake production. We further included a Middle Paleolithic flake assemblage as a point of comparison from a later time period. In the Early Pleistocene dataset, we observed an increased association between the bulb angle and other flake variables related to flake size over time, a pattern similarly found in the Middle Paleolithic assemblage. These findings suggest that, towards the Oldowan-Acheulean transition, hominins began to systematically adjust the hammer striking angle in accordance with platform variables to detach flakes of different sizes more effectively, implying the development of a more comprehensive understanding of the role of the angle of blow in flake formation by ∼1.5 Ma.

14.
J Hum Evol ; 180: 103385, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37229946

RESUMO

During the middle Pliocene (∼3.8-3.2 Ma), both Australopithecus afarensis and Kenyanthropus platyops are known from the Turkana Basin, but between 3.60 and 3.44 Ma, most hominin fossils are found on the west side of Lake Turkana. Here, we describe a new hominin locality (ET03-166/168, Area 129) from the east side of the lake, in the Lokochot Member of the Koobi Fora Formation (3.60-3.44 Ma). To reconstruct the paleoecology of the locality and its surroundings, we combine information from sedimentology, the relative abundance of associated mammalian fauna, phytoliths, and stable isotopes from plant wax biomarkers, pedogenic carbonates, and fossil tooth enamel. The combined evidence provides a detailed view of the local paleoenvironment occupied by these Pliocene hominins, where a biodiverse community of primates, including hominins, and other mammals inhabited humid, grassy woodlands in a fluvial floodplain setting. Between <3.596 and 3.44 Ma, increases in woody vegetation were, at times, associated with increases in arid-adapted grasses. This suggests that Pliocene vegetation included woody species that were resilient to periods of prolonged aridity, resembling vegetation structure in the Turkana Basin today, where arid-adapted woody plants are a significant component of the ecosystem. Pedogenic carbonates indicate more woody vegetation than other vegetation proxies, possibly due to differences in temporospatial scale and ecological biases in preservation that should be accounted for in future studies. These new hominin fossils and associated multiproxy paleoenvironmental indicators from a single locale through time suggest that early hominin species occupied a wide range of habitats, possibly including wetlands within semiarid landscapes. Local-scale paleoecological evidence from East Turkana supports regional evidence that middle Pliocene eastern Africa may have experienced large-scale, climate-driven periods of aridity. This information extends our understanding of hominin environments beyond the limits of simple wooded, grassy, or mosaic environmental descriptions.


Assuntos
Hominidae , Animais , Ecossistema , Fósseis , Biodiversidade , Plantas , Mamíferos , Poaceae , Carbonatos , Evolução Biológica , Quênia
15.
Mol Cell Proteomics ; 20: 100133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34391888

RESUMO

MS is the most effective method to directly identify peptides presented on human leukocyte antigen (HLA) molecules. However, current standard approaches often use 500 million or more cells as input to achieve high coverage of the immunopeptidome, and therefore, these methods are not compatible with the often limited amounts of tissue available from clinical tumor samples. Here, we evaluated microscaled basic reversed-phase fractionation to separate HLA peptide samples offline followed by ion mobility coupled to LC-MS/MS for analysis. The combination of these two separation methods enabled identification of 20% to 50% more peptides compared with samples analyzed without either prior fractionation or use of ion mobility alone. We demonstrate coverage of HLA immunopeptidomes with up to 8107 distinct peptides starting with as few as 100 million cells. The increased sensitivity obtained using our methods can provide data useful to improve HLA-binding prediction algorithms as well as to enable detection of clinically relevant epitopes such as neoantigens.


Assuntos
Antígenos de Neoplasias/análise , Antígenos de Histocompatibilidade Classe I/análise , Peptídeos/análise , Linhagem Celular , Fracionamento Químico , Cromatografia Líquida , Humanos , Espectrometria de Mobilidade Iônica , Neoplasias/química , Espectrometria de Massas em Tandem
16.
Am J Hum Biol ; 35(4): e23842, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36463096

RESUMO

OBJECTIVES: Investigations of early childhood growth among small-scale populations are essential for understanding human life history variation and enhancing the ability to serve such communities through global public health initiatives. This study characterizes early childhood growth trajectories and identifies differences in growth patterns relative to international references among Daasanach semi-nomadic pastoralist children living in a hot, arid region of northern Kenya. METHODS: A large sample of height and weight measures were collected from children (N = 1756; total observations = 4508; age = 0-5 years) between 2018 and 2020. Daasanach growth was compared to international reference standards and Daasanach-specific centile growth curves and pseudo-velocity models were generated using generalized additive models for location scale and size. RESULTS: Compared to World Health Organization (WHO) reference, relatively few Daasanach children were stunted (14.3%), while a large proportion were underweight (38.5%) and wasted (53.6%). Additionally, Daasanach children had a distinctive pattern of growth, marked by an increase in linear growth velocity after 24 months of age and relatively high linear growth velocity throughout the rest of early childhood. CONCLUSIONS: These results identify a unique pattern of early childhood growth faltering among children in a small-scale population and may reflect a thermoregulatory adaptation to their hot, arid environment. As linear growth and weight gain remain important indicators of health, the results of this study provide insight into growth velocity variations. This study has important implications for global public health efforts to identify and address sources of early growth faltering and undernutrition in small-scale populations.


Assuntos
Clima Desértico , Crescimento e Desenvolvimento , Aumento de Peso , Quênia , Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Crescimento e Desenvolvimento/fisiologia , Aumento de Peso/fisiologia , Organização Mundial da Saúde , Regulação da Temperatura Corporal/fisiologia , Temperatura Alta
17.
Water Int ; 48(1): 63-86, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38800511

RESUMO

This article quantifies Daasanach water insecurity experiences in Northern Kenya, examines how water insecurity is associated with water borrowing and psychosocial stress, and evaluates if water borrowing mitigates the stress from water insecurity. Of 133 households interviewed in 7 communities, 94% were water insecure and 74.4% borrowed water three or more times in the prior month. Regression analyses demonstrate water borrowing frequency moderates the relationship between water insecurity and psychosocial stress. Only those who rarely or never borrowed water reported greater stress with higher water insecurity. The coping mechanism of water borrowing may help blunt water insecurity-related stress.

18.
Lancet Oncol ; 23(1): 172-184, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34895481

RESUMO

BACKGROUND: Predictive biomarkers could allow more precise use of immune checkpoint inhibitors (ICIs) in treating advanced cancers. Given the central role of HLA molecules in immunity, variation at the HLA loci could differentially affect the response to ICIs. The aim of this epidemiological study was to determine the effect of HLA-A*03 as a biomarker for predicting response to immunotherapy. METHODS: In this epidemiological study, we investigated the clinical outcomes (overall survival, progression free survival, and objective response rate) after treatment for advanced cancer in eight cohorts of patients: three observational cohorts of patients with various types of advanced tumours (the Memorial Sloan Kettering Integrated Mutation Profiling of Actionable Cancer Targets [MSK-IMPACT] cohort, the Dana-Farber Cancer Institute [DFCI] Profile cohort, and The Cancer Genome Atlas) and five clinical trials of patients with advanced bladder cancer (JAVELIN Solid Tumour) or renal cell carcinoma (CheckMate-009, CheckMate-010, CheckMate-025, and JAVELIN Renal 101). In total, these cohorts included 3335 patients treated with various ICI agents (anti-PD-1, anti-PD-L1, and anti-CTLA-4 inhibitors) and 10 917 patients treated with non-ICI cancer-directed therapeutic approaches. We initially modelled the association of HLA amino-acid variation with overall survival in the MSK-IMPACT discovery cohort, followed by a detailed analysis of the association between HLA-A*03 and clinical outcomes in MSK-IMPACT, with replication in the additional cohorts (two further observational cohorts and five clinical trials). FINDINGS: HLA-A*03 was associated in an additive manner with reduced overall survival after ICI treatment in the MSK-IMPACT cohort (HR 1·48 per HLA-A*03 allele [95% CI 1·20-1·82], p=0·00022), the validation DFCI Profile cohort (HR 1·22 per HLA-A*03 allele, 1·05-1·42; p=0·0097), and in the JAVELIN Solid Tumour clinical trial for bladder cancer (HR 1·36 per HLA-A*03 allele, 1·01-1·85; p=0·047). The HLA-A*03 effect was observed across ICI agents and tumour types, but not in patients treated with alternative therapies. Patients with HLA-A*03 had shorter progression-free survival in the pooled patient population from the three CheckMate clinical trials of nivolumab for renal cell carcinoma (HR 1·31, 1·01-1·71; p=0·044), but not in those receiving control (everolimus) therapies. Objective responses were observed in none of eight HLA-A*03 homozygotes in the ICI group (compared with 59 [26·6%] of 222 HLA-A*03 non-carriers and 13 (17·1%) of 76 HLA-A*03 heterozygotes). HLA-A*03 was associated with shorter progression-free survival in patients receiving ICI in the JAVELIN Renal 101 randomised clinical trial for renal cell carcinoma (avelumab plus axitinib; HR 1·59 per HLA-A*03 allele, 1·16-2·16; p=0·0036), but not in those receiving control (sunitinib) therapy. Objective responses were recorded in one (12·5%) of eight HLA-A*03 homozygotes in the ICI group (compared with 162 [63·8%] of 254 HLA-A*03 non-carriers and 40 [55·6%] of 72 HLA-A*03 heterozygotes). HLA-A*03 was associated with impaired outcome in meta-analysis of all 3335 patients treated with ICI at genome-wide significance (p=2·01 × 10-8) with no evidence of heterogeneity in effect (I2 0%, 95% CI 0-0·76) INTERPRETATION: HLA-A*03 is a predictive biomarker of poor response to ICI. Further evaluation of HLA-A*03 is warranted in randomised trials. HLA-A*03 carriage could be considered in decisions to initiate ICI in patients with cancer. FUNDING: National Institutes of Health, Merck KGaA, and Pfizer.


Assuntos
Antígeno HLA-A3/genética , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Alelos , Biomarcadores , Estudos Epidemiológicos , Humanos , Neoplasias/imunologia , Neoplasias/mortalidade
19.
BMC Infect Dis ; 22(1): 833, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357829

RESUMO

Forecasts of the trajectory of an infectious agent can help guide public health decision making. A traditional approach to forecasting fits a computational model to structured data and generates a predictive distribution. However, human judgment has access to the same data as computational models plus experience, intuition, and subjective data. We propose a chimeric ensemble-a combination of computational and human judgment forecasts-as a novel approach to predicting the trajectory of an infectious agent. Each month from January, 2021 to June, 2021 we asked two generalist crowds, using the same criteria as the COVID-19 Forecast Hub, to submit a predictive distribution over incident cases and deaths at the US national level either two or three weeks into the future and combined these human judgment forecasts with forecasts from computational models submitted to the COVID-19 Forecasthub into a chimeric ensemble. We find a chimeric ensemble compared to an ensemble including only computational models improves predictions of incident cases and shows similar performance for predictions of incident deaths. A chimeric ensemble is a flexible, supportive public health tool and shows promising results for predictions of the spread of an infectious agent.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Julgamento , Previsões , Saúde Pública , Simulação por Computador , Modelos Estatísticos
20.
Am J Hum Biol ; 34(6): e23715, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34942040

RESUMO

OBJECTIVES: Thirst is an evolved central homeostatic feedback system that helps regulate body water for survival. Little research has examined how early development and exposure to extreme environments and water availability affect thirst perception, particularly outside Western settings. Therefore, we compared two indicators of perceived thirst (current thirst and pleasantness of drinking water) using visual scales among Tsimane' forager-horticulturalists in the hot-humid Bolivian Amazon and Daasanach agro-pastoralists in hot-arid Northern Kenya. METHODS: We examined how these measures of perceived thirst were associated with hydration status (urine specific gravity), ambient temperatures, birth season, age, and population-specific characteristics for 607 adults (n = 378 Tsimane', n = 229 Daasanach) aged 18+ using multi-level mixed-effect regressions. RESULTS: Tsimane' had higher perceived thirst than Daasanach. Across populations, hydration status was unrelated to both measures of thirst. There was a significant interaction between birth season and temperature on pleasantness of drinking water, driven by Kenya data. Daasanach born in the wet season (in utero during less water availability) had blunted pleasantness of drinking water at higher temperatures compared to those born in the dry season (in utero during greater water availability). CONCLUSIONS: Our findings suggest hydration status is not a reliable predictor of thirst perceptions in extreme-hot environments with ad libitum drinking. Rather, our findings, which require additional confirmation, point to the importance of water availability during gestation in affecting thirst sensitivity to heat and water feedback mechanisms, particularly in arid environments. Thirst regulation will be increasingly important to understand given climate change driven exposures to extreme heat and water insecurity.


Assuntos
Água Potável , Sede , Adulto , Comparação Transcultural , Desidratação , Humanos , Percepção , Sede/fisiologia
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