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1.
Nat Commun ; 15(1): 5763, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982051

ABSTRACT

While high circulating tumor DNA (ctDNA) levels are associated with poor survival for multiple cancers, variant-specific differences in the association of ctDNA levels and survival have not been examined. Here we investigate KRAS ctDNA (ctKRAS) variant-specific associations with overall and progression-free survival (OS/PFS) in first-line metastatic pancreatic ductal adenocarcinoma (mPDAC) for patients receiving chemoimmunotherapy ("PRINCE", NCT03214250), and an independent cohort receiving standard of care (SOC) chemotherapy. For PRINCE, higher baseline plasma levels are associated with worse OS for ctKRAS G12D (log-rank p = 0.0010) but not G12V (p = 0.7101), even with adjustment for clinical covariates. Early, on-therapy clearance of G12D (p = 0.0002), but not G12V (p = 0.4058), strongly associates with OS for PRINCE. Similar results are obtained for the SOC cohort, and for PFS in both cohorts. These results suggest ctKRAS G12D but not G12V as a promising prognostic biomarker for mPDAC and that G12D clearance could also serve as an early biomarker of response.


Subject(s)
Biomarkers, Tumor , Carcinoma, Pancreatic Ductal , Circulating Tumor DNA , Pancreatic Neoplasms , Proto-Oncogene Proteins p21(ras) , Humans , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/mortality , Carcinoma, Pancreatic Ductal/blood , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/drug therapy , Proto-Oncogene Proteins p21(ras)/genetics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/blood , Pancreatic Neoplasms/mortality , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/drug therapy , Female , Male , Circulating Tumor DNA/blood , Circulating Tumor DNA/genetics , Middle Aged , Aged , Biomarkers, Tumor/blood , Biomarkers, Tumor/genetics , Prognosis , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Mutation , Progression-Free Survival , Neoplasm Metastasis
2.
Cancer Immunol Res ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38990554

ABSTRACT

Innate inflammation promotes tumor development, although the role of innate inflammatory cytokines in established human tumors is unclear. Here we report clinical and translational results from a phase Ib trial testing whether IL-1ß blockade in human pancreatic cancer would alleviate myeloid immunosuppression and reveal antitumor T-cell responses to PD-1 blockade. Patients with treatment-naïve advanced pancreatic ductal adenocarcinoma (n=10) were treated with canakinumab, a high-affinity monoclonal human anti-interleukin-1ß (IL-1ß), the PD-1 blocking antibody spartalizumab, and gemcitabine/n(ab)paclitaxel. Analysis of paired peripheral blood from patients in the trial versus patients receiving multiagent chemotherapy showed a modest increase in HLA-DR+CD38+ activated CD8+ T cells and a decrease in circulating monocytic myeloid-derived suppressor cells (MDSCs) by flow cytometry for patients in the trial, but not in controls. Similarly, we used patient serum to differentiate monocytic MDSCs in vitro and showed that functional inhibition of T-cell proliferation was reduced when using on-treatment serum samples from patients in the trial but not when using serum from patients treated with chemotherapy alone. Within the tumor we observed few changes in suppressive myeloid-cell populations or activated T cells as assessed by single-cell transcriptional profiling or multiplex immunofluorescence, although increases in CD8+ T cells suggest that improvements in the tumor immune microenvironment might be revealed by a larger study. Overall, the data indicate that exposure to PD-1 and IL-1ß blockade induced a modest reactivation of peripheral CD8+ T cells and decreased circulating monocytic MDSCs; however, these changes did not lead to similarly uniform alterations in the tumor microenvironment.

3.
Hortic Res ; 11(6): uhae095, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38840937

ABSTRACT

Tomato fruit ripening is triggered by the demethylation of key genes, which alters their transcriptional levels thereby initiating and propagating a cascade of physiological events. What is unknown is how these processes are altered when fruit are ripened using postharvest practices to extend shelf-life, as these practices often reduce fruit quality. To address this, postharvest handling-induced changes in the fruit DNA methylome and transcriptome, and how they correlate with ripening speed, and ripening indicators such as ethylene, abscisic acid, and carotenoids, were assessed. This study comprehensively connected changes in physiological events with dynamic molecular changes. Ripening fruit that reached 'Turning' (T) after dark storage at 20°C, 12.5°C, or 5°C chilling (followed by 20°C rewarming) were compared to fresh-harvest fruit 'FHT'. Fruit stored at 12.5°C had the biggest epigenetic marks and alterations in gene expression, exceeding changes induced by postharvest chilling. Fruit physiological and chronological age were uncoupled at 12.5°C, as the time-to-ripening was the longest. Fruit ripening to Turning at 12.5°C was not climacteric; there was no respiratory or ethylene burst, rather, fruit were high in abscisic acid. Clear differentiation between postharvest-ripened and 'FHT' was evident in the methylome and transcriptome. Higher expression of photosynthetic genes and chlorophyll levels in 'FHT' fruit pointed to light as influencing the molecular changes in fruit ripening. Finally, correlative analyses of the -omics data putatively identified genes regulated by DNA methylation. Collectively, these data improve our interpretation of how tomato fruit ripening patterns are altered by postharvest practices, and long-term are expected to help improve fruit quality.

4.
Mol Ther ; 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38845196

ABSTRACT

Systemic administration of adeno-associated virus (AAV) vectors for spinal cord gene therapy has challenges including toxicity at high doses and pre-existing immunity that reduces efficacy. Intrathecal (IT) delivery of AAV vectors into cerebral spinal fluid can avoid many issues, although distribution of the vector throughout the spinal cord is limited, and vector entry to the periphery sometimes initiates hepatotoxicity. Here we performed biopanning in non-human primates (NHPs) with an IT injected AAV9 peptide display library. We identified top candidates by sequencing inserts of AAV DNA isolated from whole tissue, nuclei, or nuclei from transgene-expressing cells. These barcoded candidates were pooled with AAV9 and compared for biodistribution and transgene expression in spinal cord and liver of IT injected NHPs. Most candidates displayed increased retention in spinal cord compared with AAV9. Greater spread from the lumbar to the thoracic and cervical regions was observed for several capsids. Furthermore, several capsids displayed decreased biodistribution to the liver compared with AAV9, providing a high on-target/low off-target biodistribution. Finally, we tested top candidates in human spinal cord organoids and found them to outperform AAV9 in efficiency of transgene expression in neurons and astrocytes. These capsids have potential to serve as leading-edge delivery vehicles for spinal cord-directed gene therapies.

5.
Cancer Res Commun ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38934093

ABSTRACT

PURPOSE: To investigate the cellular and molecular mechanisms associated with targeting CD30-expressing Hodgkin Lymphoma (HL) and immune checkpoint modulation induced by combination therapies of CTLA-4 and PD1. PATIENTS AND METHODS: Phase 1/2, multicenter, open-label, trial NCT01896999 enrolled patients with refractory or relapsed HL (R/R HL) after one or more lines of therapy, with adequate performance status and organ function. Using peripheral blood, we assessed soluble proteins, cell composition, T cell clonality, and tumor antigen-specific antibodies in 54 patients enrolled in the phase 1 component of the trial. RESULTS: NCT01896999 reported high (>75%) overall objective response rates with brentuximab-vedotin (BV) in combination with ipilimumab (I) and/or nivolumab (N) in patients with R/R HL. We observed durable increase in soluble PD-1 and plasmacytoid dendritic cells as well as decreases in plasma CCL17, ANGPT2, MMP12, IL13, and CXCL13 in N-containing regimens (BV+N and BV+I+N) compared with BV+I (p<0.05). Non-responders and patients with short progression free-survival showed elevated CXCL9, CXCL13, CD5, CCL17, adenosine-deaminase, and MUC16 at baseline or after one treatment cycle and a higher prevalence of NY-ESO-1-specific autoantibodies (p<0.05). CONCLUSIONS: The results suggest a circulating tumor-immune-derived signature of BV±I+N treatment resistance that may be useful for patient stratification in combination checkpoint therapy.

6.
Mil Med ; 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38829170

ABSTRACT

INTRODUCTION: Providing effective treatment for debilitating chronic pain is a challenge among many populations including military service members. Cognitive behavioral therapy for chronic pain (CBT-CP) is a leading psychological pain treatment. Pain catastrophizing is a pivotal mediator of pain-related outcomes. The purpose of this study was (1) to identify patient subgroups who differ in response to CBT-CP and (2) to explore the characteristics that define these patient subgroups. The overall goal was to obtain a better understanding of factors that may influence response to CBT-CP. MATERIALS AND METHODS: This study was a secondary analysis of data from a clinical trial of 149 U.S. active duty service members with chronic pain. Participants underwent group-based CBT-CP for 6 weeks and completed pre- and posttreatment assessments. Finite mixture models were employed to identify subgroups in treatment response, with pain impact score as the primary outcome measure. RESULTS: We identified two classes of nearly equal size with distinct pain impact responses. One class reported improved pain impact scores following CBT-CP. This improvement was significantly associated with lower (better) baseline depression scores and greater improvement in posttreatment pain catastrophizing. In contrast, the other class reported slightly worse mean pain impact scores following CBT-CP treatment; this response was not related to baseline depression or change in pain catastrophizing. CONCLUSIONS: Our findings demonstrate that a sizable proportion of individuals with chronic pain may not respond to group-based CBT-CP and may require a more individualized treatment approach.

7.
Eur Respir J ; 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38901883

ABSTRACT

BACKGROUND: We recently demonstrated that elexacaftor/tezacaftor/ivacaftor (ETI) improves the lung clearance index (LCI) and abnormalities in lung morphology detected by magnetic resonance imaging (MRI) in adolescent and adult patients with cystic fibrosis (CF). However, real-world data on the effect of ETI on these sensitive outcomes of lung structure and function in school-age children with CF have not been reported. The aim of this study was therefore to examine the effect of ETI on the LCI and the lung MRI score in children with CF and one or two F508del alleles aged 6 to 11 years. METHODS: This prospective, observational, multicenter, post-approval study assessed the longitudinal LCI up to 12 months and the lung MRI score before and three months after initiation of ETI. RESULTS: A total of 107 children with CF including 40 heterozygous for F508del and a minimal function mutation (F/MF) and 67 homozygous for F508del (F/F) were enrolled in this study. Treatment with ETI improved the LCI in F/MF children (-1.0; IQR, -2.0 to -0.1; p<0.01) and F/F children (-0.8; IQR, -1.9 to -0.2; p<0.001) from 3 months onwards. Further, ETI improved the MRI global score in F/MF (-4.0; IQR, -9.0 to 0.0; p<0.01) and F/F children (-3.5; IQR, -7.3 to -0.8; p<0.001). CONCLUSIONS: ETI improves early abnormalities in lung ventilation and morphology in school-age children with CF and at least one F508del alleles in a real-world setting. Our results support early initiation of ETI to reduce or even prevent lung disease progression in school-age children with CF.

9.
JAMA Ophthalmol ; 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38842900
10.
Nutrients ; 16(12)2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38931165

ABSTRACT

Iron deficiency is the number one nutritional problem worldwide. Iron uptake is regulated at the intestine and is highly influenced by the gut microbiome. Blood from the intestines drains directly into the liver, informing iron status and gut microbiota status. Changes in either iron or the microbiome are tightly correlated with the development of metabolic dysfunction-associated steatotic liver disease (MASLD). To investigate the underlying mechanisms of the development of MASLD that connect altered iron metabolism and gut microbiota, we compared specific pathogen free (SPF) or germ-free (GF) mice, fed a normal or low-iron diet. SPF mice on a low-iron diet showed reduced serum triglycerides and MASLD. In contrast, GF low-iron diet-fed mice showed increased serum triglycerides and did not develop hepatic steatosis. SPF mice showed significant changes in liver lipid metabolism and increased insulin resistance that was dependent upon the presence of the gut microbiota. We report that total body loss of mitochondrial iron importer Mitoferrin2 (Mfrn2-/-) exacerbated the development of MASLD on a low-iron diet with significant lipid metabolism alterations. Our study demonstrates a clear contribution of the gut microbiome, dietary iron, and Mfrn2 in the development of MASLD and metabolic syndrome.


Subject(s)
Gastrointestinal Microbiome , Liver , Animals , Female , Male , Mice , Fatty Liver/etiology , Insulin Resistance , Iron/metabolism , Iron Deficiencies , Iron, Dietary/administration & dosage , Lipid Metabolism , Liver/metabolism , Mice, Inbred C57BL , Mice, Knockout , Mitochondria/metabolism , Mitochondrial Proteins/metabolism , Triglycerides/blood
11.
Endocrinology ; 165(7)2024 May 27.
Article in English | MEDLINE | ID: mdl-38889246

ABSTRACT

Follicular androgens are important for successful ovulation and fertilization. The classical nuclear androgen receptor (AR) is a transcription factor expressed in the cells of the ovarian follicle. Androgen actions can also occur via membrane androgen receptor SLC39A9. Studies in fish ovary demonstrated that androgens bind to SLC39A9 and increase intracellular zinc to regulate ovarian cell function. To determine if SLC39A9 is expressed and functional in the key cell types of the mammalian ovulatory follicle, adult female cynomolgus macaques underwent ovarian stimulation. Ovaries or ovarian follicular aspirates were harvested at 0, 12, 24, and 36 hours after human chorionic gonadotropin (hCG). SLC39A9 and AR mRNA and protein were present in granulosa, theca, and vascular endothelial cells across the entire 40-hour ovulatory window. Testosterone, bovine serum albumin-conjugated testosterone (BSA-T), and androstenedione stimulated zinc influx in granulosa, theca, and vascular endothelial cells. The SLC39A9-selective agonist (-)-epicatechin also stimulated zinc influx in vascular endothelial cells. Taken together, these data support the conclusion that SLC39A9 activation via androgen induces zinc influx in key ovarian cells. Testosterone, BSA-T, and androstenedione each increased proliferation in vascular endothelial cells, indicating the potential involvement of SLC39A9 in ovulatory angiogenesis. Vascular endothelial cell migration also increased after treatment with testosterone, but not after treatment with BSA-T or androstenedione, suggesting that androgens stimulate vascular endothelial cell migration through nuclear AR but not SLC39A9. The presence of SLC39A9 receptors and SLC39A9 activation by follicular androstenedione concentrations suggests that androgen activation of ovarian SLC39A9 may regulate ovulatory changes in the mammalian follicle.


Subject(s)
Macaca fascicularis , Ovarian Follicle , Ovulation , Receptors, Androgen , Animals , Female , Receptors, Androgen/metabolism , Receptors, Androgen/genetics , Ovarian Follicle/metabolism , Ovarian Follicle/drug effects , Zinc/metabolism , Testosterone/metabolism , Endothelial Cells/metabolism , Cation Transport Proteins/metabolism , Cation Transport Proteins/genetics , Cell Membrane/metabolism , Theca Cells/metabolism , Granulosa Cells/metabolism , Granulosa Cells/drug effects , Chorionic Gonadotropin/pharmacology
12.
J Exp Psychol Gen ; 153(6): 1415-1424, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38695797

ABSTRACT

Image memorability, the likelihood that a person will remember a particular image, has been shown to be an intrinsic property of the image that is distinct from many other visual and cognitive features. Research thus far has not identified particular visual features that can sufficiently explain this intrinsic memorability, but one possibility is that more and less memorable images differ in their statistical regularity (i.e., how prototypical or distinctive they are). Statistical regularity is known to affect detection time for images, such that stimuli with higher statistical regularity can be detected with shorter presentation directions. Therefore, in the present study, we probed whether memorability affects how quickly an image can be detected. High- and low-memorability images were presented in an intact/scrambled task wherein participants were asked to indicate whether they saw an intact image or noise, and we estimated the presentation duration necessary for participants to reach 70.7% accuracy. Across two experiments using different stimulus materials, we observed and then replicated that more memorable images are associated with shorter detection thresholds than those for less memorable images. The results support the idea that memorable stimuli may better match stored templates used for image perception and/or recognition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Subject(s)
Pattern Recognition, Visual , Humans , Female , Male , Young Adult , Adult , Pattern Recognition, Visual/physiology , Recognition, Psychology/physiology , Visual Perception/physiology , Mental Recall/physiology
13.
Respirology ; 29(7): 635-636, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38751039
14.
Nurs Res ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38809559

ABSTRACT

BACKGROUND: People experiencing homelessness are at greater risk of exposure and poor health outcomes from COVID-19. Yet, little data exists on the prevalence and correlates of COVID-19 among homeless populations. To mitigate the spread and severity, uptake of the COVID-19 vaccine is needed. This can be challenging among youth experiencing homelessness who are more likely to be unvaccinated when compared to stably housed youth. OBJECTIVE: We conducted this study to determine the prevalence and correlates of COVID-19 among youth experiencing homelessness. METHODS: We examined experiences of COVID-19 symptoms, self-report of infection, rates of COVID-19 antibodies and distinguished between natural and vaccinated immunity among youth experiencing homelessness (N = 265) recruited in one large metropolitan area in the South. RESULTS: Based on self-report, very few participants experienced any symptoms, and 80% had never been diagnosed with COVID-19. Of those with COVID-19 antibodies (68%), the proportion with antibodies resulting from natural infection was 44%. The vaccination rate was 42%. Younger and vaccinated participants and those in shelters were likelier to have COVID-19 antibodies. Black and Hispanic youth were more likely than White youth to have had COVID-19. Those who adopted only one or two prevention behaviors were more likely to acquire a natural infection than those who adopted three or more prevention behaviors. DISCUSSION: Youth experiencing homelessness report low vaccination rates, disrupted access to health care and social supports, and underlying chronic conditions, which may explain why they face poorer outcomes when infected with COVID-19. Vaccination and risk mitigation strategies to combat the high prevalence of COVID-19 are especially needed for sheltered youth who are at high risk yet are often asymptomatic.

15.
J Cogn Neurosci ; 36(8): 1715-1740, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38739561

ABSTRACT

Predictive coding accounts of perception state that the brain generates perceptual predictions in the service of processing incoming sensory data. These predictions are hypothesized to be afforded by the brain's ability to internalize useful patterns, that is, statistical regularities, from the environment. We have previously argued that the N300 ERP component serves as an index of the brain's use of representations of (real-world) statistical regularities. However, we do not yet know whether overt attention is necessary in order for this process to engage. We addressed this question by presenting stimuli of either high or low real-world statistical regularity in terms of their representativeness (good/bad exemplars of natural scene categories) to participants who either fully attended the stimuli or were distracted by another task (attended/distracted conditions). Replicating past work, N300 responses were larger to bad than to good scene exemplars, and furthermore, we demonstrate minimal impacts of distraction on N300 effects. Thus, it seems that overtly focused attention is not required to maintain the brain's sensitivity to real-world statistical regularity. Furthermore, in an exploratory analysis, we showed that providing additional, artificial regularities, formed by altering the proportions of good and bad exemplars within blocks, further enhanced the N300 effect in both attended and distracted conditions, shedding light on the relationship between statistical regularities learned in the real world and those learned within the context of an experiment.


Subject(s)
Attention , Brain , Electroencephalography , Humans , Attention/physiology , Female , Male , Young Adult , Brain/physiology , Adult , Evoked Potentials/physiology , Photic Stimulation , Adolescent , Reaction Time/physiology , Pattern Recognition, Visual/physiology
16.
Med Res Arch ; 12(4)2024 Apr.
Article in English | MEDLINE | ID: mdl-38818307

ABSTRACT

Background: In recent years, cervical cancer screening among Black women in the United States has declined, followed by increased incidence and mortality. We aim to evaluate the individual, sociocultural, and structural barriers to cervical cancer screening in relationship to the exam technique barriers. Methods: Participants received cervical cancer self-screening kits in the mail. They returned their samples and a quantitative survey developed from the Health Information National Trends Survey (HINTS) modules designed to address the known individual, sociocultural, and structural barriers to screening. We established the fourteen attributes of cervical cancer screening techniques from prior work. Participants then shared their experiences in a semi-structured qualitative interview informed by the Theoretical Domains Framework (TDF) to explore the answers to the survey questions. We coded themes from the interviews. Women were grouped as younger (30-45 years) and older (46-65 years). Results: Of the 41 women completing the study, 21 were in the younger age group (mean 37.3, SD 4.7), and 20 were in the older age group (56.5 (5.5)). All participants self-identified as African American/Black and were due for cervical cancer screening. Women indicated that individual, sociocultural, and structural barriers influenced their cervical cancer screening, but the most significant barrier was the speculum-based technique itself. Three positive attributes and eight negative attributes significantly differed by screening technique, favoring the self-screening technique. Conclusions: The self-screening technique for screening for cervical cancer is feasible and acceptable to this group of Black women.

17.
Vaccine ; 2024 May 24.
Article in English | MEDLINE | ID: mdl-38796328

ABSTRACT

INTRODUCTION: Human papillomavirus (HPV) vaccination rates among females are lower than the World Health Organization target and vaccination rates specifically among adult females are even much lower. METHODS: We systematically evaluated individual socioeconomic and health-related characteristics associated with HPV vaccination initiation and vaccination series completion among adult females (PROSPERO: CRD42023445721). We performed a literature search on December 14, 2022, and supplemented the search on August 1, 2023. We pooled appropriate multivariable-adjusted results using an inverse variance random-effects model and expressed the results as odds ratios with associated 95 % confidence intervals. A point pooled significantly increased/decreased odds of 30-69 % was regarded to be strongly associated, and ≥ 70 % was very strongly associated. RESULTS: We included 63 cross-sectional studies. There were strongly increased odds of vaccination initiation among White women compared with Black or Asian women, and those with higher education, health insurance, a history of sexually transmitted infection (STI), receipt of influenza vaccination in the preceding year, not married/cohabiting, not smoking, using contraception, and having visited a healthcare provider in the preceding year. We observed very strongly increased odds of vaccination initiation among those younger and having been born in the country of study. Similarly, there were strongly increased odds of completing the vaccination series for the same variables as initiating vaccination, except for higher education, prior STI, smoking and contraception use. Additional variables associated with strongly increased odds of vaccination series completion not seen in initiation were higher annual household income, being lesbian/bisexual, and having a primary care physician. We observed very strongly increased odds of vaccination series completion similar to vaccination initiation but including for White compared with Black women, higher education, and prior cervical cancer screening. CONCLUSIONS: These individual characteristics may be the key to identifying women at increased risk of not being vaccinated against HPV and could inform targeted messaging to drive HPV vaccination.

18.
Cancer ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38809542

ABSTRACT

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) surveillance is recommended for some individuals with a pathogenic or likely pathogenic variant (PV/LPV) in a PDAC susceptibility gene; the recommendation is often dependent on family history of PDAC. This study aimed to describe PDAC family history in individuals with PDAC who underwent genetic testing to determine the appropriateness of including a family history requirement in these recommendations. METHODS: Individuals with PDAC with a germline heterozygous PV/LPV in ATM, BRCA1, BRCA2, EPCAM, MLH1, MSH2, MSH6, PALB2, or PMS2 (PV/LPV carriers) were assessed for family history of PDAC in first-degree relatives (FDRs) or second-degree relatives (SDRs) from nine institutions. A control group of individuals with PDAC without a germline PV/LPV was also assessed. RESULTS: The study included 196 PV/LPV carriers and 1184 controls. In the PV/LPV carriers, 25.5% had an affected FDR and/or SDR compared to 16.9% in the control group (p = .004). PV/LPV carriers were more likely to have an affected FDR compared to the controls (p = .003) but there was no statistical difference when assessing only affected SDRs (p = .344). CONCLUSIONS: Most PV/LPV carriers who developed PDAC did not have a close family history of PDAC and would not have met most current professional societies' recommendations for consideration of PDAC surveillance before diagnosis. However, PV/LPV carriers were significantly more likely to have a family history of PDAC, particularly an affected FDR. These findings support family history as a risk modifier in PV/LPV carriers, and highlight the need to identify other risk factors.

19.
Front Microbiol ; 15: 1352666, 2024.
Article in English | MEDLINE | ID: mdl-38784810

ABSTRACT

Flow pulses mobilize particulate organic matter (POM) in streams from the surrounding landscape and streambed. This POM serves as a source of energy and nutrients, as well as a means for organismal dispersal, to downstream communities. In the barren terrestrial landscape of the McMurdo Dry Valleys (MDV) of Antarctica, benthic microbial mats occupying different in-stream habitat types are the dominant POM source in the many glacier-fed streams. Many of these streams experience daily flow peaks that mobilize POM, and diatoms recovered from underlying stream sediments suggest that mat-derived diatoms in the POM are retained there through hyporheic exchange. Yet, 'how much' and 'when' different in-stream habitat types contribute to POM diatom assemblages is unknown. To quantify the contribution of different in-stream habitat types to POM diatom assemblages, we collected time-integrated POM samples over four diel experiments, which spanned a gradient of flow conditions over three summers. Diatoms from POM samples were identified, quantified, and compared with dominant habitat types (i.e., benthic 'orange' mats, marginal 'black' mats, and bare sediments). Like bulk POM, diatom cell concentrations followed a clockwise hysteresis pattern with stream discharge over the daily flow cycles, indicating supply limitation. Diatom community analyses showed that different habitat types harbor distinct diatom communities, and mixing models revealed that a substantial proportion of POM diatoms originated from bare sediments during baseflow conditions. Meanwhile, orange and black mats contribute diatoms to POM primarily during daily flow peaks when both cell concentrations and discharge are highest, making mats the most important contributors to POM diatom assemblages at high flows. These observations may help explain the presence of mat-derived diatoms in hyporheic sediments. Our results thus indicate a varying importance of different in-stream habitats to POM generation and export on daily to seasonal timescales, with implications for biogeochemical cycling and the local diatom metacommunity.

20.
PLoS One ; 19(5): e0302998, 2024.
Article in English | MEDLINE | ID: mdl-38809849

ABSTRACT

BACKGROUND: Benfotiamine provides an important novel therapeutic direction in Alzheimer's disease (AD) with possible additive or synergistic effects to amyloid targeting therapeutic approaches. OBJECTIVE: To conduct a seamless phase 2A-2B proof of concept trial investigating tolerability, safety, and efficacy of benfotiamine, a prodrug of thiamine, as a first-in-class small molecule oral treatment for early AD. METHODS: This is the protocol for a randomized, double-blind, placebo-controlled 72-week clinical trial of benfotiamine in 406 participants with early AD. Phase 2A determines the highest safe and well-tolerated dose of benfotiamine to be carried forward to phase 2B. During phase 2A, real-time monitoring of pre-defined safety stopping criteria in the first approximately 150 enrollees will help determine which dose (600 mg or 1200 mg) will be carried forward into phase 2B. The phase 2A primary analysis will test whether the rate of tolerability events (TEs) is unacceptably high in the high-dose arm compared to placebo. The primary safety endpoint in phase 2A is the rate of TEs compared between active and placebo arms, at each dose. The completion of phase 2A will seamlessly transition to phase 2B without pausing or stopping the trial. Phase 2B will assess efficacy and longer-term safety of benfotiamine in a larger group of participants through 72 weeks of treatment, at the selected dose. The co-primary efficacy endpoints in phase 2B are CDR-Sum of Boxes and ADAS-Cog13. Secondary endpoints include safety and tolerability measures; pharmacokinetic measures of thiamine and its esters, erythrocyte transketolase activity as blood markers of efficacy of drug delivery; ADCS-ADL-MCI; and MoCA. CONCLUSION: The BenfoTeam trial utilizes an innovative seamless phase 2A-2B design to achieve proof of concept. It includes an adaptive dose decision rule, thus optimizing exposure to the highest and best-tolerated dose. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT06223360, registered on January 25, 2024. https://classic.clinicaltrials.gov/ct2/show/NCT06223360.


Subject(s)
Alzheimer Disease , Thiamine , Humans , Alzheimer Disease/drug therapy , Thiamine/analogs & derivatives , Thiamine/therapeutic use , Thiamine/administration & dosage , Thiamine/adverse effects , Double-Blind Method , Male , Female , Aged , Middle Aged , Treatment Outcome , Prodrugs/adverse effects , Prodrugs/therapeutic use , Prodrugs/administration & dosage , Prodrugs/pharmacokinetics
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