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1.
Nat Immunol ; 21(8): 938-949, 2020 08.
Article in English | MEDLINE | ID: mdl-32572242

ABSTRACT

The central nervous system (CNS) is classically viewed as immune-privileged; however, recent advances highlight interactions between the peripheral immune system and CNS in controlling infections and tissue homeostasis. Tissue-resident memory (TRM) CD8+ T cells in the CNS are generated after brain infections, but it is unknown whether CNS infection is required to generate brain TRM cells. We show that peripheral infections generate antigen-specific CD8+ memory T cells in the brain that adopt a unique TRM signature. Upon depletion of circulating and perivascular memory T cells, this brain signature was enriched and the surveilling properties of brain TRM cells was revealed by intravital imaging. Notably, peripherally induced brain TRM cells showed evidence of rapid activation and enhanced cytokine production and mediated protection after brain infections. These data reveal that peripheral immunizations can generate brain TRM cells and will guide potential use of T cells as therapeutic strategies against CNS infections and neurological diseases.


Subject(s)
Brain/immunology , CD8-Positive T-Lymphocytes/immunology , Central Nervous System Infections/immunology , Immunologic Memory/immunology , Animals , Bacterial Infections/immunology , Brain/cytology , Lymphocyte Activation/immunology , Mice , Virus Diseases/immunology
2.
Mol Cell ; 83(19): 3457-3469.e7, 2023 10 05.
Article in English | MEDLINE | ID: mdl-37802023

ABSTRACT

Circadian gene transcription is fundamental to metabolic physiology. Here we report that the nuclear receptor REV-ERBα, a repressive component of the molecular clock, forms circadian condensates in the nuclei of mouse liver. These condensates are dictated by an intrinsically disordered region (IDR) located in the protein's hinge region which specifically concentrates nuclear receptor corepressor 1 (NCOR1) at the genome. IDR deletion diminishes the recruitment of NCOR1 and disrupts rhythmic gene transcription in vivo. REV-ERBα condensates are located at high-order transcriptional repressive hubs in the liver genome that are highly correlated with circadian gene repression. Deletion of the IDR disrupts transcriptional repressive hubs and diminishes silencing of target genes by REV-ERBα. This work demonstrates physiological circadian protein condensates containing REV-ERBα whose IDR is required for hub formation and the control of rhythmic gene expression.


Subject(s)
Circadian Clocks , Mice , Animals , Circadian Clocks/genetics , Circadian Rhythm/genetics , Nuclear Receptor Subfamily 1, Group D, Member 1/genetics , Nuclear Receptor Subfamily 1, Group D, Member 1/metabolism , Liver/metabolism , Gene Expression
3.
Cell ; 160(1-2): 324-38, 2015 Jan 15.
Article in English | MEDLINE | ID: mdl-25557080

ABSTRACT

Pancreatic cancer is one of the most lethal malignancies due to its late diagnosis and limited response to treatment. Tractable methods to identify and interrogate pathways involved in pancreatic tumorigenesis are urgently needed. We established organoid models from normal and neoplastic murine and human pancreas tissues. Pancreatic organoids can be rapidly generated from resected tumors and biopsies, survive cryopreservation, and exhibit ductal- and disease-stage-specific characteristics. Orthotopically transplanted neoplastic organoids recapitulate the full spectrum of tumor development by forming early-grade neoplasms that progress to locally invasive and metastatic carcinomas. Due to their ability to be genetically manipulated, organoids are a platform to probe genetic cooperation. Comprehensive transcriptional and proteomic analyses of murine pancreatic organoids revealed genes and pathways altered during disease progression. The confirmation of many of these protein changes in human tissues demonstrates that organoids are a facile model system to discover characteristics of this deadly malignancy.


Subject(s)
Carcinoma, Pancreatic Ductal/pathology , Models, Biological , Organ Culture Techniques , Organoids/pathology , Pancreatic Neoplasms/pathology , Animals , Humans , Mice , Mice, Inbred C57BL , Mice, Nude , Pancreas/metabolism , Pancreas/pathology
4.
Nature ; 619(7970): 539-544, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37316662

ABSTRACT

Understanding the nature and origin of the precursor material to terrestrial planets is key to deciphering the mechanisms and timescales of planet formation1. Nucleosynthetic variability among rocky Solar System bodies can trace the composition of planetary building blocks2-5. Here we report the nucleosynthetic composition of silicon (µ30Si), the most abundant refractory planet-building element, in primitive and differentiated meteorites to identify terrestrial planet precursors. Inner Solar System differentiated bodies, including Mars, record µ30Si deficits of -11.0 ± 3.2 parts per million to -5.8 ± 3.0 parts per million whereas non-carbonaceous and carbonaceous chondrites show µ30Si excesses from 7.4 ± 4.3 parts per million to 32.8 ± 2.0 parts per million relative to Earth. This establishes that chondritic bodies are not planetary building blocks. Rather, material akin to early-formed differentiated asteroids must represent a major planetary constituent. The µ30Si values of asteroidal bodies correlate with their accretion ages, reflecting progressive admixing of a µ30Si-rich outer Solar System material to an initially µ30Si-poor inner disk. Mars' formation before chondrite parent bodies is necessary to avoid incorporation of µ30Si-rich material. In contrast, Earth's µ30Si composition necessitates admixing of 26 ± 9 per cent of µ30Si-rich outer Solar System material to its precursors. The µ30Si compositions of Mars and proto-Earth are consistent with their rapid formation by collisional growth and pebble accretion less than three million years after Solar System formation. Finally, Earth's nucleosynthetic composition for s-process sensitive (molybdenum and zirconium) and siderophile (nickel) tracers are consistent with pebble accretion when volatility-driven processes during accretion and the Moon-forming impact are carefully evaluated.

5.
Mol Cell ; 80(6): 933-934, 2020 12 17.
Article in English | MEDLINE | ID: mdl-33338407

ABSTRACT

Pfeil et al., (2020) examine the mechanism of Gi-stimulated Ca2+ release in cells and find an unexpected role for Gαq in Gßγ-dependent activation of phospholipase Cß (PLCß).


Subject(s)
Calcium , GTP-Binding Protein alpha Subunits, Gq-G11 , Calcium/metabolism , GTP-Binding Protein alpha Subunits, Gq-G11/metabolism , Phospholipase C beta/genetics , Phospholipase C beta/metabolism , Signal Transduction
6.
PLoS Pathog ; 20(4): e1011975, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38557892

ABSTRACT

Arboviruses can emerge rapidly and cause explosive epidemics of severe disease. Some of the most epidemiologically important arboviruses, including dengue virus (DENV), Zika virus (ZIKV), Chikungunya (CHIKV) and yellow fever virus (YFV), are transmitted by Aedes mosquitoes, most notably Aedes aegypti and Aedes albopictus. After a mosquito blood feeds on an infected host, virus enters the midgut and infects the midgut epithelium. The virus must then overcome a series of barriers before reaching the mosquito saliva and being transmitted to a new host. The virus must escape from the midgut (known as the midgut escape barrier; MEB), which is thought to be mediated by transient changes in the permeability of the midgut-surrounding basal lamina layer (BL) following blood feeding. Here, we present a mathematical model of the within-mosquito population dynamics of DENV (as a model system for mosquito-borne viruses more generally) that includes the interaction of the midgut and BL which can account for the MEB. Our results indicate a dose-dependency of midgut establishment of infection as well as rate of escape from the midgut: collectively, these suggest that the extrinsic incubation period (EIP)-the time taken for DENV virus to be transmissible after infection-is shortened when mosquitoes imbibe more virus. Additionally, our experimental data indicate that multiple blood feeding events, which more closely mimic mosquito-feeding behavior in the wild, can hasten the course of infections, and our model predicts that this effect is sensitive to the amount of virus imbibed. Our model indicates that mutations to the virus which impact its replication rate in the midgut could lead to even shorter EIPs when double-feeding occurs. Mechanistic models of within-vector viral infection dynamics provide a quantitative understanding of infection dynamics and could be used to evaluate novel interventions that target the mosquito stages of the infection.


Subject(s)
Aedes , Dengue Virus , Dengue , Zika Virus Infection , Zika Virus , Animals , Gastrointestinal Tract , Mosquito Vectors
7.
Proc Natl Acad Sci U S A ; 120(27): e2302785120, 2023 07 04.
Article in English | MEDLINE | ID: mdl-37364124

ABSTRACT

The increasing use of nuclear energy sources inevitably raises the risk of accidental or deliberate radiation exposure and associated immune dysfunction. However, the extent to which radiation exposure impacts memory CD8 T cells, potent mediators of immunity to recurring intracellular infections and malignancies, remains understudied. Using P14 CD8 T cell chimeric mice (P14 chimeras) with an lymphocytic choriomeningitis virus (LCMV) infection model, we observed that sublethal (5Gy) whole-body irradiation (WBI) induced a rapid decline in the number of naive (TN) and P14 circulating memory CD8 T cells (TCIRCM), with the former being more susceptible to radiation-induced numeric loss. While TN cell numbers rapidly recovered, as previously described, the number of P14 TCIRCM cells remained low at least 9 mo after radiation exposure. Additionally, the remaining P14 TCIRCM in irradiated hosts exhibited an inefficient transition to a central memory (CD62L+) phenotype compared to nonirradiated P14 chimeras. WBI also resulted in long-lasting T cell intrinsic deficits in memory CD8 T cells, including diminished cytokine and chemokine production along with impaired secondary expansion upon cognate Ag reencounter. Irradiated P14 chimeras displayed significantly higher bacterial burden after challenge with Listeria monocytogenes expressing the LCMV GP33-41 epitope relative to nonirradiated controls, likely due to radiation-induced numerical and functional impairments. Taken together, our findings suggest that sublethal radiation exposure caused a long-term numerical, impaired differentiation, and functional dysregulation in preexisting TCIRCM, rendering previously protected hosts susceptible to reinfection.


Subject(s)
Lymphocytic Choriomeningitis , Whole-Body Irradiation , Mice , Animals , Neoplasm Recurrence, Local , CD8-Positive T-Lymphocytes , Lymphocytic choriomeningitis virus , Immunologic Memory , Mice, Inbred C57BL
8.
PLoS Pathog ; 19(10): e1011720, 2023 10.
Article in English | MEDLINE | ID: mdl-37824591

ABSTRACT

Sepsis, an amplified immune response to systemic infection, is characterized by a transient cytokine storm followed by chronic immune dysfunction. Consequently, sepsis survivors are highly susceptible to newly introduced infections, suggesting sepsis can influence the function and composition of the naïve CD8 T cell pool and resulting pathogen-induced primary CD8 T cell responses. Here, we explored the extent to which sepsis induces phenotypic and functional changes within the naïve CD8 T cell pool. To interrogate this, the cecal ligation and puncture (CLP) mouse model of polymicrobial sepsis was used. In normal, non-septic mice, we show type-I interferon (IFN I)-mediated signaling plays an important role in driving the phenotypic and functional heterogeneity in the naïve CD8 T cell compartment leading to increased representation of Ly6C+ naïve CD8 T cells. In response to viral infection after sepsis resolution, naïve Ly6C+ CD8 T cells generated more primary effector and memory CD8 T cells with slower conversion to a central memory CD8 T cell phenotype (Tcm) than Ly6C- naïve CD8 T cells. Importantly, as a potent inducer of cytokine storm and IFN I production, sepsis leads to increased representation of Ly6C+ naïve CD8 T cells that maintained their heightened ability to respond (i.e., effector and memory CD8 T cell accumulation and cytokine production) to primary LCMV infection. Lastly, longitudinal analyses of peripheral blood samples obtained from septic patients revealed profound changes in CD8 T cell subset composition and frequency compared to healthy controls. Thus, sepsis has the capacity to alter the composition of naïve CD8 T cells, directly influencing primary CD8 T cell responses to newly introduced infections.


Subject(s)
Cytokine Release Syndrome , Sepsis , Humans , Mice , Animals , CD8-Positive T-Lymphocytes , Immunity, Innate , Phenotype , Mice, Inbred C57BL , Immunologic Memory
9.
Nat Immunol ; 14(8): 858-66, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23793062

ABSTRACT

Although T cell activation can result from signaling via T cell antigen receptor (TCR) alone, physiological T cell responses require costimulation via the coreceptor CD28. Through the use of an N-ethyl-N-nitrosourea-mutagenesis screen, we identified a mutation in Rltpr. We found that Rltpr was a lymphoid cell-specific, actin-uncapping protein essential for costimulation via CD28 and the development of regulatory T cells. Engagement of TCR-CD28 at the immunological synapse resulted in the colocalization of CD28 with both wild-type and mutant Rltpr proteins. However, the connection between CD28 and protein kinase C-θ and Carma1, two key effectors of CD28 costimulation, was abrogated in T cells expressing mutant Rltpr, and CD28 costimulation did not occur in those cells. Our findings provide a more complete model of CD28 costimulation in which Rltpr has a key role.


Subject(s)
CARD Signaling Adaptor Proteins/immunology , CD28 Antigens/immunology , Carrier Proteins/immunology , Guanylate Cyclase/immunology , Protein Kinase C/immunology , Receptors, Antigen, T-Cell/immunology , T-Lymphocytes, Regulatory/immunology , Amino Acid Sequence , Animals , Base Sequence , Carrier Proteins/genetics , Flow Cytometry , Lymphocyte Activation/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Microfilament Proteins , Microscopy, Confocal , Molecular Sequence Data , Mutagenesis, Site-Directed , Sequence Alignment , Sequence Analysis, DNA , Specific Pathogen-Free Organisms
10.
Acc Chem Res ; 57(9): 1287-1297, 2024 05 07.
Article in English | MEDLINE | ID: mdl-38626119

ABSTRACT

The growing list of physiologically important protein-protein interactions (PPIs) has amplified the need for compounds to target topologically complex biomolecular surfaces. In contrast to small molecules, peptide and protein mimics can exhibit three-dimensional shape complementarity across a large area and thus have the potential to significantly expand the "druggable" proteome. Strategies to stabilize canonical protein secondary structures without sacrificing side-chain content are particularly useful in the design of peptide-based chemical probes and therapeutics.Substitution of the backbone amide in peptides represents a subtle chemical modification with profound effects on conformation and stability. Studies focused on N-alkylation have already led to broad-ranging applications in peptidomimetic design. Inspired by nonribosomal peptide natural products harboring amide N-oxidations, we envisioned that main-chain hydrazide and hydroxamate bonds would impose distinct conformational preferences and offer unique opportunities for backbone diversification. This Account describes our exploration of peptide N-amination as a strategy for stabilizing canonical protein folds and for the structure-based design of soluble amyloid mimics.We developed a general synthetic protocol to access N-amino peptides (NAPs) on solid support. In an effort to stabilize ß-strand conformation, we designed stitched peptidomimetics featuring covalent tethering of the backbone N-amino substituent to the preceding residue side chain. Using a combination of NMR, X-ray crystallography, and molecular dynamics simulations, we discovered that backbone N-amination alone could significantly stabilize ß-hairpin conformation in multiple models of folding. Our studies revealed that the amide NH2 substituent in NAPs participates in cooperative noncovalent interactions that promote ß-sheet secondary structure. In contrast to Cα-substituted α-hydrazino acids, we found that N-aminoglycine and its N'-alkylated derivatives instead stabilize polyproline II (PPII) conformation. The reactivity of hydrazides also allows for late-stage peptide macrocyclization, affording novel covalent surrogates of side-chain-backbone H-bonds.The pronounced ß-sheet propensity of Cα-substituted α-hydrazino acids prompted us to target amyloidogenic proteins using NAP-based ß-strand mimics. Backbone N-amination was found to render aggregation-prone lead sequences soluble and resistant to proteolysis. Inhibitors of Aß and tau identified through N-amino scanning blocked protein aggregation and the formation of mature fibrils in vitro. We further identified NAP-based single-strand and cross-ß tau mimics capable of inhibiting the prion-like cellular seeding activity of recombinant and patient-derived tau fibrils.Our studies establish backbone N-amination as a valuable addition to the peptido- and proteomimetic tool kit. α-Hydrazino acids show particular promise as minimalist ß-strand mimics that retain side-chain information. Late-stage derivatization of hydrazides also provides facile entry into libraries of backbone-edited peptides. We anticipate that NAPs will thus find applications in the development of optimally constrained folds and modulators of PPIs.


Subject(s)
Peptides , Alkylation , Peptides/chemistry , Peptides/chemical synthesis
11.
J Immunol ; 210(2): 168-179, 2023 01 15.
Article in English | MEDLINE | ID: mdl-36480268

ABSTRACT

Long-lasting sepsis-induced immunoparalysis has been principally studied in primary (1°) memory CD8 T cells; however, the impact of sepsis on memory CD8 T cells with a history of repeated cognate Ag encounters is largely unknown but important in understanding the role of sepsis in shaping the pre-existing memory CD8 T cell compartment. Higher-order memory CD8 T cells are crucial in providing immunity against common pathogens that reinfect the host or are generated by repeated vaccination. In this study, we analyzed peripheral blood from septic patients and show that memory CD8 T cells with defined Ag specificity for recurring CMV infection proliferate less than bulk populations of central memory CD8 T cells. Using TCR-transgenic T cells to generate 1° and higher-order (quaternary [4°]) memory T cells within the same host, we demonstrate that the susceptibility and loss of both memory subsets are similar after sepsis induction, and sepsis diminished Ag-dependent and -independent (bystander) functions of these memory subsets equally. Both the 1° and 4° memory T cell populations proliferated in a sepsis-induced lymphopenic environment; however, due to the intrinsic differences in baseline proliferative capacity, expression of receptors (e.g., CD127/CD122), and responsiveness to homeostatic cytokines, 1° memory T cells become overrepresented over time in sepsis survivors. Finally, IL-7/anti-IL-7 mAb complex treatment early after sepsis induction preferentially rescued the proliferation and accumulation of 1° memory T cells, whereas recovery of 4° memory T cells was less pronounced. Thus, inefficient recovery of repeatedly stimulated memory cells after polymicrobial sepsis induction leads to changes in memory T cell pool composition, a notion with important implications in devising strategies to recover the number and function of pre-existing memory CD8 T cells in sepsis survivors.


Subject(s)
Lymphopenia , Sepsis , Humans , Animals , Mice , Memory T Cells , CD8-Positive T-Lymphocytes , Cytokines/metabolism , Lymphopenia/metabolism , Immunologic Memory , Mice, Inbred C57BL
12.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Article in English | MEDLINE | ID: mdl-35165189

ABSTRACT

During the last deglaciation, dozens of glacial outburst floods-among the largest known floods on Earth-scoured the Channeled Scabland landscape of eastern Washington. Over this same period, deformation of the Earth's crust in response to the growth and decay of ice sheets changed the topography by hundreds of meters. Here, we investigated whether glacial isostatic adjustment affected routing of the Missoula floods and incision of the Channeled Scabland from an impounded, glacial Lake Columbia. We used modern topography corrected for glacial isostatic adjustment as an input to flood models that solved the depth-averaged, shallow water equations and compared the results to erosion constraints. Results showed that floods could have traversed and eroded parts of two major tracts of the Channeled Scabland-Telford-Crab Creek and Cheney-Palouse-near 18 ka, whereas glacial isostatic adjustment limited flow into the Cheney-Palouse tract at 15.5 ka. Partitioning of flow between tracts was governed by tilting of the landscape, which affected the filling and overspill of glacial Lake Columbia directly upstream of the tracts. These results highlight the impact of glacial isostatic adjustment on megaflood routing and landscape evolution.

13.
Proc Natl Acad Sci U S A ; 119(24): e2112496119, 2022 06 14.
Article in English | MEDLINE | ID: mdl-35671421

ABSTRACT

Thermodynamic preferences to form non-native conformations are crucial for understanding how nucleic acids fold and function. However, they are difficult to measure experimentally because this requires accurately determining the population of minor low-abundance (<10%) conformations in a sea of other conformations. Here, we show that melting experiments enable facile measurements of thermodynamic preferences to adopt nonnative conformations in DNA and RNA. The key to this "delta-melt" approach is to use chemical modifications to render specific minor non-native conformations the major state. The validity and robustness of delta-melt is established for four different non-native conformations under various physiological conditions and sequence contexts through independent measurements of thermodynamic preferences using NMR. Delta-melt is faster relative to NMR, simple, and cost-effective and enables thermodynamic preferences to be measured for exceptionally low-populated conformations. Using delta-melt, we obtained rare insights into conformational cooperativity, obtaining evidence for significant cooperativity (1.0 to 2.5 kcal/mol) when simultaneously forming two adjacent Hoogsteen base pairs. We also measured the thermodynamic preferences to form G-C+ and A-T Hoogsteen and A-T base open states for nearly all 16 trinucleotide sequence contexts and found distinct sequence-specific variations on the order of 2 to 3 kcal/mol. This rich landscape of sequence-specific non-native minor conformations in the DNA double helix may help shape the sequence specificity of DNA biochemistry. Thus, melting experiments can now be used to access thermodynamic information regarding regions of the free energy landscape of biomolecules beyond the native folded and unfolded conformations.


Subject(s)
DNA , Nucleic Acid Conformation , RNA , Base Sequence , DNA/chemistry , Freezing , RNA/chemistry , Thermodynamics , Ultraviolet Rays
14.
Breast Cancer Res ; 26(1): 101, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38872192

ABSTRACT

BACKGROUND: Little is known about how use of chemotherapy has evolved in breast cancer patients. We therefore describe chemotherapy patterns for women with stage I-IIIA breast cancer in the Optimal Breast Cancer Chemotherapy Dosing (OBCD) Study using data from KPNC (Kaiser Permanente Northern California) and KPWA (Kaiser Permanente Washington). FINDINGS: Among 33,670 women, aged 18 + y, diagnosed with primary stage I-IIIA breast cancer at KPNC and KPWA from 2006 to 2019, we explored patterns of intravenous chemotherapy use, defined here as receipt of intravenous cytotoxic drugs and/or anti-HER2 therapies. We evaluated trends in chemotherapy receipt, duration over which chemotherapy was received, and number of associated infusion visits. In secondary analyses, we stratified by receipt of anti-HER2 therapies (trastuzumab and/or pertuzumab), given their longer duration. 38.9% received chemotherapy intravenously, declining from 40.2% in 2006 to 35.6% in 2019 (p-trend < 0.001). Among 13,089 women receiving chemotherapy, neoadjuvant treatment increased (4.1-14.7%; p-trend < 0.001), as did receipt of anti-HER2 therapies (20.8-30.9%) (p-trend < 0.001). The average treatment duration increased (5.3 to 6.0 months; p-trend < 0.001), as did the number of infusion visits (10.8 to 12.5; p-trend < 0.001). For those receiving anti-HER2 therapies, treatment duration and average number of visits decreased; among those not receiving anti-HER2 therapies, number of visits increased, with no change in duration. CONCLUSIONS: While the prevalence of chemotherapy receipt has decreased over time, the use of neoadjuvant chemotherapy has increased, as has use of anti-HER2 therapies; duration and number of administration visits have also increased. Understanding these trends is useful to inform clinical and administrative planning.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Breast Neoplasms , Neoadjuvant Therapy , Neoplasm Staging , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Breast Neoplasms/epidemiology , Middle Aged , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoadjuvant Therapy/trends , Receptor, ErbB-2/metabolism , Trastuzumab/therapeutic use , Chemotherapy, Adjuvant/trends , Young Adult
15.
Int J Cancer ; 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38970396

ABSTRACT

For patients with breast cancer, delays in chemotherapy initiation have been adversely associated with recurrence and survival. We evaluated patient-level factors associated with delayed chemotherapy initiation, from both diagnosis and surgery, in a community-based cohort of women with early-stage breast cancer. For the Optimal Breast Cancer Chemotherapy Dosing study, we identified a cohort of 34,109 women diagnosed with stage I-IIIA breast cancer at two U.S. integrated healthcare delivery systems between 2004 and 2019. We used logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI) to identify patient factors associated with delays in chemotherapy initiation after diagnosis (≥90 days) and surgery (≥60 days). Among 10,968 women receiving adjuvant chemotherapy, 21.1% experienced delays in chemotherapy initiation after diagnosis and 21.3% after surgery. Older age, non-Hispanic Black and Hispanic race and ethnicity, and ER+ and/or PR+ disease were associated with increased likelihood of delays to chemotherapy initiation after diagnosis and surgery. People diagnosed in 2012-2019 (vs. 2005-2011), with a higher grade and larger tumor size were less likely to experience delays. Other factors were associated with a higher likelihood of delays specifically from diagnosis (earlier stage, mastectomy vs. breast-conserving surgery), or surgery (higher comorbidity, increased nodal number). Women diagnosed with breast cancer who were at highest risk of progression and recurrence were less likely to experience delays in chemotherapy initiation after diagnosis and surgery. Understanding reasons for chemotherapy delays beyond patient factors may be potentially important to reduce risk of breast cancer recurrence and progression.

16.
Anal Chem ; 96(15): 5807-5814, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38573874

ABSTRACT

Understanding the reactivity of metal cations with various reaction gases in inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) is important to determine the best gas to use for a given analyte/interference pair. In this study, nitric oxide (NO) was investigated as the reaction gas following previous experimental designs. The reactions with 50 elements were investigated to examine periodic trends in reactivity, validate theoretical modeling of reaction enthalpies as a method to screen reactant gases, and provide a baseline data set for potential in-line gas separation methods. ICP-MS/MS studies involving actinides are typically limited to Th, U, and Pu, with analyses of Np and Am rarely reported in the literature. To date, only two previous methods have investigated the use of NO in ICP-MS/MS analyses. To showcase the utility of NO, a method was developed to measure 239Pu in the presence of environmental matrix constituent and other actinides, like what could be expected from postdetonation debris, with no chemical separation prior to analysis. 239Pu+ was reacted to form 239Pu16O+, eliminating interferences derived from the sample matrix by measuring the 239Pu+ intensity at m/z = 255 (239Pu16O+). To validate NO for 238U1H+ interference removal in environmental matrices, standard reference materials were diluted to 1 mg/g of solution and spiked to 0.05 pg/g of 239Pu and 1 µg/g 238U (Pu/U = 5 × 10-8). Measured 239Pu concentrations were within 6% of the spiked value. These results demonstrate that reliable 239Pu measurements can be made at levels relevant to nuclear forensics without the need for extensive chemical matrix separation prior to analysis.

17.
Breast Cancer Res Treat ; 203(3): 565-574, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37923962

ABSTRACT

PURPOSE: Most cytotoxic drugs are dosed using body surface area (BSA), yet not all cancer patients receive the full BSA-determined dose. Prior work suggests that breast cancer patients who are obese are more likely to experience dose reduction than normal weight patients. However, the factors driving dose reduction remain unclear. METHODS: In 452 women diagnosed with stage I-IIIA primary breast cancer at Kaiser Permanente Northern California, we evaluated the association between obesity and dose reduction, and further explored other factors in relation to dose reduction, including various sociodemographic characteristics, tumor characteristics, and comorbidities. Study participants were a part of the Pathways Study, diagnosed between 2006 and 2013 and treated with cyclophosphamide + doxorubicin, followed by paclitaxel (ACT). Dose reduction was assessed using first cycle dose proportion (FCDP) and average relative dose intensity (ARDI), a metric of dose intensity over the course of chemotherapy. RESULTS: Overall, 8% of participants received a FCDP < 90% and 21.2% had an ARDI < 90%, with dose reduction increasing with body mass index. In adjusted logistic regression models, obese women had 4.1-fold higher odds of receiving an ARDI < 90% than normal weight women (95% CI: 1.9-8.9; p-trend = 0.0006). Increasing age was positively associated with an ADRI < 90%, as was the presence of comorbidity. Dose reduction was less common in later calendar years. CONCLUSION: Results offer insight on factors associated with chemotherapy dosing for a common breast cancer regimen. Larger studies are required to evaluate relevance to other regimens, and further work will be needed to determine whether dose reductions impact outcomes in obese women.


Subject(s)
Breast Neoplasms , Delivery of Health Care, Integrated , Fumarates , beta-Alanine/analogs & derivatives , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/epidemiology , Breast Neoplasms/complications , Drug Tapering , Retrospective Studies , Cyclophosphamide , Obesity/complications , Obesity/epidemiology , Obesity/drug therapy , Antineoplastic Combined Chemotherapy Protocols/adverse effects
18.
J Urol ; : 101097JU0000000000004070, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38848543

ABSTRACT

PURPOSE: Nonmuscle-invasive bladder cancer (NMIBC) has high recurrence rates and is often treated with mitomycin C (MMC) and bacillus Calmette-Guérin (BCG). Their efficacy relies on phase 2 enzyme metabolism and immune response activation, respectively. Dietary isothiocyanates, phytochemicals in cruciferous vegetables, are phase 2 enzyme inducers and immunomodulators, and may impact treatment outcomes. We investigated the modifying effects of cruciferous vegetable and isothiocyanate intake on recurrence risk following MMC or BCG treatment. MATERIALS AND METHODS: Self-reported cruciferous vegetable intake, estimated isothiocyanate intake, and urinary isothiocyanate metabolites were collected from 1158 patients with incident NMIBC in the prospective Be-Well Study. Hazard ratios (HRs) and 95% CIs were calculated from Cox proportional hazards regression models for risk of first recurrences, and random effects Cox shared frailty models for multiple recurrences. RESULTS: Over median follow-up of 23 months, 343 (30%) recurrences occurred. Receipt of MMC and BCG was associated with decreased risks of first recurrence (MMC: HR = 0.58; 95% CI: 0.46-0.73; BCG: HR = 0.66; 95% CI: 0.49-0.88) and multiple recurrences (MMC: HR = 0.55; 95% CI: 0.44-0.68; BCG: HR = 0.72; 95% CI: 0.55-0.95). Patients receiving BCG and having high intake (>2.4 servings/mo), but not low intake, of raw cruciferous vegetables had reduced risk of recurrence (HR: 0.56; 95% CI: 0.36-0.86; P for interaction = .02) and multiple recurrences (HR: 0.51; 95% CI: 0.34-0.77; P for interaction < .001). The inverse association between MMC receipt and recurrence risk was not modified. CONCLUSIONS: For NMIBC patients who receive induction BCG, increasing consumption of raw cruciferous vegetables could be a promising strategy to attenuate recurrence risk.

19.
Plant Physiol ; 193(1): 217-228, 2023 08 31.
Article in English | MEDLINE | ID: mdl-37226328

ABSTRACT

The visualization of photosynthesis-derived reactive oxygen species has been experimentally limited to pH-sensitive probes, unspecific redox dyes, and whole-plant phenotyping. Recent emergence of probes that circumvent these limitations permits advanced experimental approaches to investigate in situ plastid redox properties. Despite growing evidence of heterogeneity in photosynthetic plastids, investigations have not addressed the potential for spatial variation in redox and/or reactive oxygen dynamics. To study the dynamics of H2O2 in distinct plastid types, we targeted the pH-insensitive, highly specific probe HyPer7 to the plastid stroma in Arabidopsis (Arabidopsis thaliana). Using HyPer7 and glutathione redox potential (EGSH) probe for redox-active green fluorescent protein 2 genetically fused to the redox enzyme human glutaredoxin-1 with live cell imaging and optical dissection of cell types, we report heterogeneities in H2O2 accumulation and redox buffering within distinct epidermal plastids in response to excess light and hormone application. Our observations suggest that plastid types can be differentiated by their physiological redox features. These data underscore the variation in photosynthetic plastid redox dynamics and demonstrate the need for cell-type-specific observations in future plastid phenotyping.


Subject(s)
Arabidopsis , Hydrogen Peroxide , Humans , Hydrogen Peroxide/metabolism , Plastids/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism , Photosynthesis , Oxidation-Reduction
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