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1.
Cureus ; 16(5): e60621, 2024 May.
Article En | MEDLINE | ID: mdl-38903282

Lance-Adams syndrome (LAS) is a rare clinical presentation of hypoxic-ischemic brain injury typically occurring in the setting of cardiac arrest. It is rare for it to be associated with respiratory failure. The advent of the COVID-19 pandemic heralded a new cause of respiratory failure, and not much is known about the occurrence of Lance-Adams syndrome in the context of COVID-19 pneumonia. A 23-year-old male was brought to the emergency department (ED) after being found unconscious at home. He had prominent generalized myoclonus in the context of COVID-19 pneumonia and a possible clonazepam overdose. Magnetic resonance imaging (MRI) of the brain with and without contrast revealed findings suggestive of hypoxic-ischemic brain injury. A diagnosis of LAS was made based on electroencephalography (EEG). As LAS typically carries a relatively favorable prognosis, aggressive treatment was pursued. This resulted in a fairly good outcome, although he had to be maintained on several antiseizure medications. Our case is a rare occurrence of Lance-Adams syndrome in the setting of respiratory failure and COVID-19 pneumonia in the absence of cardiac arrest. It is critical to distinguish myoclonic status epilepticus (MSE) from Lance-Adams syndrome due to the difference in prognosis. Our case can provide future direction for studies in a larger cohort of patients to see if LAS is frequently associated with respiratory failure secondary to COVID-19 pneumonia in the absence of cardiac arrest. It is important to consider Lance-Adams syndrome as one of the emerging neurological complications of COVID-19 pneumonia.

2.
Adv Mater ; : e2405505, 2024 May 20.
Article En | MEDLINE | ID: mdl-38767502

4D printing is an emerging field where 3D printing techniques are used to pattern stimuli-responsive materials to create morphing structures, with time serving as the fourth dimension. However, current materials utilized for 4D printing are typically soft, exhibiting an elastic modulus (E) range of 10-4 to 10 MPa during shape change. This restricts the scalability, actuation stress, and load-bearing capabilities of the resulting structures. To overcome these limitations, multiscale heterogeneous polymer composites are introduced as a novel category of stiff, thermally responsive 4D printed materials. These inks exhibit an E that is four orders of magnitude greater than that of existing 4D printed materials and offer tunable electrical conductivities for simultaneous Joule heating actuation and self-sensing capabilities. Utilizing electrically controllable bilayers as building blocks, a flat geometry is designed and printed that morphs into a 3D self-standing lifting robot, setting new records for weight-normalized load lifted and actuation stress when compared to other 3D printed actuators. Furthermore, the ink palette is employed to create and print planar lattice structures that transform into various self-supporting complex 3D shapes. These contributions are integrated into a 4D printed electrically controlled multigait crawling robotic lattice structure that can carry 144 times its own weight.

3.
Mol Ecol Resour ; : e13978, 2024 May 22.
Article En | MEDLINE | ID: mdl-38775206

Amplicon sequencing is an effective and increasingly applied method for studying viral communities in the environment. Here, we present vAMPirus, a user-friendly, comprehensive, and versatile DNA and RNA virus amplicon sequence analysis program, designed to support investigators in exploring virus amplicon sequencing data and running informed, reproducible analyses. vAMPirus intakes raw virus amplicon libraries and, by default, performs nucleotide- and amino acid-based analyses to produce results such as sequence abundance information, taxonomic classifications, phylogenies and community diversity metrics. The vAMPirus analytical framework leverages 16 different opensource tools and provides optional approaches that can increase the ratio of biological signal-to-noise and thereby reveal patterns that would have otherwise been masked. Here, we validate the vAMPirus analytical framework and illustrate its implementation as a general virus amplicon sequencing workflow by recapitulating findings from two previously published double-stranded DNA virus datasets. As a case study, we also apply the program to explore the diversity and distribution of a coral reef-associated RNA virus. vAMPirus is streamlined within Nextflow, offering straightforward scalability, standardization and communication of virus lineage-specific analyses. The vAMPirus framework is designed to be adaptable; community-driven analytical standards will continue to be incorporated as the field advances. vAMPirus supports researchers in revealing patterns of virus diversity and population dynamics in nature, while promoting study reproducibility and comparability.

4.
J Neurosci Res ; 102(4): e25331, 2024 Apr.
Article En | MEDLINE | ID: mdl-38651314

Circadian rhythms synchronize to light through the retinohypothalamic tract (RHT), which is a bundle of axons coming from melanopsin retinal ganglion cells, whose synaptic terminals release glutamate to the ventral suprachiasmatic nucleus (SCN). Activation of AMPA-kainate and NMDA postsynaptic receptors elicits the increase in intracellular calcium required for triggering the signaling cascade that ends in phase shifts. During aging, there is a decline in the synchronization of circadian rhythms to light. With electrophysiological (whole-cell patch-clamp) and immunohistochemical assays, in this work, we studied pre- and postsynaptic properties between the RHT and ventral SCN neurons in young adult (P90-120) and old (P540-650) C57BL/6J mice. Incremental stimulation intensities (applied on the optic chiasm) induced much lesser AMPA-kainate postsynaptic responses in old animals, implying a lower recruitment of RHT fibers. Conversely, a higher proportion of old SCN neurons exhibited synaptic facilitation, and variance-mean analysis indicated an increase in the probability of release in RHT terminals. Moreover, both spontaneous and miniature postsynaptic events displayed larger amplitudes in neurons from aged mice, whereas analysis of the NMDA and AMPA-kainate components (evoked by RHT electrical stimulation) disclosed no difference between the two ages studied. Immunohistochemistry revealed a bigger size in the puncta of vGluT2, GluN2B, and GluN2A of elderly animals, and the number of immunopositive particles was increased, but that of PSD-95 was reduced. All these synaptic adaptations could be part of compensatory mechanisms in the glutamatergic signaling to ameliorate the loss of RHT terminals in old animals.


Aging , Glutamic Acid , Mice, Inbred C57BL , Suprachiasmatic Nucleus , Synaptic Transmission , Animals , Mice , Suprachiasmatic Nucleus/physiology , Suprachiasmatic Nucleus/metabolism , Synaptic Transmission/physiology , Aging/physiology , Glutamic Acid/metabolism , Male , Excitatory Postsynaptic Potentials/physiology , Visual Pathways/physiology , Vesicular Glutamate Transport Protein 2/metabolism , Patch-Clamp Techniques , Receptors, N-Methyl-D-Aspartate/metabolism , Disks Large Homolog 4 Protein/metabolism
5.
Article En | MEDLINE | ID: mdl-38520044

BACKGROUND/PURPOSE: There is uncertainty about the role of prophylactic intra-abdominal drains after distal pancreatectomy. In the present study, we aimed to describe the long-term outcomes of postoperative pancreatic collections in patients who underwent a minimally invasive distal pancreatectomy (MIDP) without surgical drain placement. METHODS: From 2018 to 2022, consecutive patients who underwent a MIDP were recorded. Patients were followed at 90 days, 6 months, and in the long term. The use of interventional procedures and antibiotic therapy were documented, and the overall evolution of the collections was assessed. RESULTS: A total of 91 patients underwent MIDP; 11 were excluded; 80 were analyzed. Median age was 63 (51-73) years; 61.3% were women. Most lesions (71.3%) were malignant; 15 patients received neoadjuvant therapy. Procedures were laparoscopic (87.5%) or robotic (12.5%). Incidence of postoperative pancreatic collections was 33%; 10 patients were symptomatic. Interventional endoscopic (n = 3) or percutaneous (n = 3) procedures were required. At a follow-up of 24 (17.5-33.1) months, 18 collections resolved completely, eight partially, and one increased. CONCLUSIONS: Patients who undergo MIDP without surgical drain placement develop well-tolerated pancreatic collections. Although a minority may require endoscopic or percutaneous drainage, the majority can be managed conservatively and resolve spontaneously in the long term.

6.
JCI Insight ; 9(6)2024 Feb 06.
Article En | MEDLINE | ID: mdl-38319712

Dedifferentiation or phenotype switching refers to the transition from a proliferative to an invasive cellular state. We previously identified a 122-gene epigenetic gene signature that classifies primary melanomas as low versus high risk (denoted as Epgn1 or Epgn3). We found that the transcriptomes of the Epgn1 low-risk and Epgn3 high-risk cells are similar to the proliferative and invasive cellular states, respectively. These signatures were further validated in melanoma tumor samples. Examination of the chromatin landscape revealed differential H3K27 acetylation in the Epgn1 low-risk versus Epgn3 high-risk cell lines that corroborated with a differential super-enhancer and enhancer landscape. Melanocytic lineage genes (MITF, its targets and regulators) were associated with super-enhancers in the Epgn1 low-risk state, whereas invasiveness genes were linked with Epgn3 high-risk status. We identified the ITGA3 gene as marked by a super-enhancer element in the Epgn3 invasive cells. Silencing of ITGA3 enhanced invasiveness in both in vitro and in vivo systems, suggesting it as a negative regulator of invasion. In conclusion, we define chromatin landscape changes associated with Epgn1/Epgn3 and phenotype switching during early steps of melanoma progression that regulate transcriptional reprogramming. This super-enhancer and enhancer-driven epigenetic regulatory mechanism resulting in major changes in the transcriptome could be important in future therapeutic targeting efforts.


Histones , Melanoma , Humans , Histones/genetics , Histones/metabolism , Melanoma/pathology , Cell Dedifferentiation/genetics , Acetylation , Cell Line, Tumor , Chromatin/genetics
7.
Adv Radiat Oncol ; 9(4): 101431, 2024 Apr.
Article En | MEDLINE | ID: mdl-38406389

Purpose: Retroperitoneal sarcomas (RPS) have varied treatment practices with regard to the use of radiation therapy (RT). Preoperative RT ∼50 Gy is commonly used, but the Surgery With or Without Radiation Therapy in Untreated Nonmetastatic Retroperitoneal Sarcoma (STRASS-1) randomized trial demonstrated no improvement in abdominal recurrence-free survival with preoperative RT. Dose escalation has been proposed to improve the efficacy of preoperative RT. We analyzed RPS treated with preoperative intensity modulated proton therapy (IMPT) to an escalated dose of 63 Gy at a single institution. Methods and Materials: Patients who received preoperative RT with IMPT with RPS between January 2015 and October 2021 were reviewed. IMPT 63 Gy in 28 fractions to the clinical target volume high-risk and 50.4 Gy in 28 fractions to clinical target volume low-risk was used. Patient baseline characteristics, RT dose parameters, toxicities, margin status, and recurrence patterns were recorded. Local control was computed by Fine-Gray analysis and overall survival by Kaplan-Meier analysis. Results: Sixteen patients met the study criteria (n = 16): 12 primary and 4 isolated local recurrences. Median age was 62 years (IQR, 43.5-66 years) and 62.5% were male; 10 were liposarcoma. The median maximum tumor diameter was 19.9 cm (IQR, 12-24 cm). With a median follow-up of 18 months (IQR, 11.5-37 months), the estimated 3-year freedom from local failure rate was 68.2% (95% CI, 41.7%-94.7%); 3-year overall survival (OS) rate was 68.8% (95% CI, 41.9%-95.8%). No Radiation Therapy Oncology Group grade ≥3 acute or late toxicities were noted. Conclusions: In our RPS cohort, preoperative dose-escalated RT to 63 Gy demonstrated comparable local control without G3 acute toxicities. Given the high local recurrence rates of RPS, this approach warrants further study to validate these results and identify patients most likely to benefit from therapy.

8.
Geobiology ; 22(1): e12586, 2024.
Article En | MEDLINE | ID: mdl-38385602

The formation of skeletal structures composed of different calcium carbonate polymorphs (e.g. aragonite and calcite) appears to be both biologically and environmentally regulated. Among environmental factors influencing aragonite and calcite precipitation, changes in seawater conditions-primarily in the molar ratio of magnesium and calcium during so-called 'Calcite' (mMg:mCa below 2) or 'Aragonite' seas (mMg:mCa above 2)-have had profound impacts on the distribution and performance of marine calcifiers throughout Earth's history. Nonetheless, the fossil record shows that some species appear to have counteracted such changes and kept their skeleton polymorph unaltered. Here, the aragonitic octocoral Heliopora coerulea and the aragonitic scleractinian Montipora digitata were exposed to Calcite Sea-like mMg:mCa with various levels of magnesium and calcium concentration, and changes in both the mineralogy (i.e. CaCO3 polymorph) and gene expression were monitored. Both species maintained aragonite deposition at lower mMg:mCa ratios, while concurrent calcite presence was only detected in M. digitata. Despite a strong variability between independent experimental replicates for both species, the expression for a set of putative calcification-related genes, including known components of the M. digitata skeleton organic matrix (SkOM), was found to consistently change at lower mMg:mCa. These results support the previously proposed involvements of the SkOM in counteracting decreases in seawater mMg:mCa. Although no consistent expression changes in calcium and magnesium transporters were observed, down-regulation calcium channels in H. coerulea in one experimental replicate and at an mMg:mCa of 2.5, pointing to a possible active calcium uptake regulation by the corals under altered mMg:mCa.


Anthozoa , Calcium Carbonate , Animals , Calcium Carbonate/analysis , Calcium/metabolism , Anthozoa/chemistry , Anthozoa/metabolism , Magnesium/analysis , Oceans and Seas
9.
Adv Mater ; 36(8): e2307858, 2024 Feb.
Article En | MEDLINE | ID: mdl-38063841

4D printing is an emerging field where 3D printing techniques are used to pattern stimuli-responsive materials to create morphing structures, with time serving as the fourth dimension. However, current materials utilized for 4D printing are typically soft, exhibiting an elastic modulus (E) range of 10-4 to 10 MPa during shape change. This restricts the scalability, actuation stress, and load-bearing capabilities of the resulting structures. To overcome these limitations, multiscale heterogeneous polymer composites are introduced as a novel category of stiff, thermally responsive 4D printed materials. These inks exhibit an E that is four orders of magnitude greater than that of existing 4D printed materials and offer tunable electrical conductivities for simultaneous Joule heating actuation and self-sensing capabilities. Utilizing electrically controllable bilayers as building blocks, a flat geometry that morphs into a 3D self-standing lifting robot is designed and printed, setting new records for weight-normalized load lifted and actuation stress when compared to other 3D printed actuators. Furthermore, this ink palette is employed to create and print planar lattice structures that transform into various self-supporting complex 3D shapes. Finally these inks are integrated into a 4D printed electrically controlled multigait crawling robotic lattice structure that can carry 144 times its own weight.

10.
Emerg Infect Dis ; 30(1): 136-140, 2024 Jan.
Article En | MEDLINE | ID: mdl-38147063

We assessed tuberculosis (TB) diagnostic delays among patients with TB and COVID-19 in California, USA. Among 58 persons, 43% experienced TB diagnostic delays, and a high proportion (83%) required hospitalization for TB. Even when viral respiratory pathogens circulate widely, timely TB diagnostic workup for at-risk persons remains critical for reducing TB-related illness.


COVID-19 , Tuberculosis , Humans , Delayed Diagnosis , COVID-19/diagnosis , California/epidemiology , Treatment Outcome , Tuberculosis/diagnosis , Tuberculosis/drug therapy , Tuberculosis/epidemiology , COVID-19 Testing
11.
Am J Trop Med Hyg ; 109(6): 1303-1310, 2023 12 06.
Article En | MEDLINE | ID: mdl-37972312

Surveillance methods that permit rapid detection of circulating pathogens in low-resource settings are desperately needed. In this study, we evaluated a mosquito bloodmeal-based surveillance method ("xenosurveillance") in rural Guatemala. Twenty households from two villages (Los Encuentros and Chiquirines) in rural southwest Guatemala were enrolled and underwent weekly prospective surveillance from August 2019 to December 2019 (16 weeks). When febrile illness was reported in a household, recently blood-fed mosquitoes were collected from within dwellings and blood samples taken from each member of the household. Mosquitoes were identified to species and blood sources identified by sequencing. Shotgun metagenomic sequencing was used to identify circulating viruses. Culex pipiens (60.9%) and Aedes aegypti (18.6%) were the most abundant mosquitoes collected. Bloodmeal sources were most commonly human (32.6%) and chicken (31.6%), with various other mammal and avian hosts detected. Several mosquito-specific viruses were detected, including Culex orthophasma virus. Human pathogens were not detected. Therefore, xenosurveillance may require more intensive sampling to detect human pathogens in Guatemala and ecologically similar localities in Central America.


Aedes , Culex , Viruses , Animals , Humans , Guatemala/epidemiology , Prospective Studies , Mosquito Vectors , Mammals , Chickens
12.
JMIR Res Protoc ; 12: e48210, 2023 Nov 13.
Article En | MEDLINE | ID: mdl-37955959

BACKGROUND: Early identification of mental disorder symptoms is crucial for timely treatment and reduction of recurring symptoms and disabilities. A tool to help individuals recognize warning signs is important. We posit that such a tool would have to rely on longitudinal analysis of patterns and trends in the individual's daily activities and mood, which can now be captured through data from wearable activity trackers, speech recordings from mobile devices, and the individual's own description of their mental state. In this paper, we describe such a tool developed by our team to detect early signs of depression, anxiety, and stress. OBJECTIVE: This study aims to examine three questions about the effectiveness of machine learning models constructed based on multimodal data from wearables, speech, and self-reports: (1) How does speech about issues of personal context differ from speech while reading a neutral text, what type of speech data are more helpful in detecting mental health indicators, and how is the quality of the machine learning models influenced by multilanguage data? (2) Does accuracy improve with longitudinal data collection and how, and what are the most important features? and (3) How do personalized machine learning models compare against population-level models? METHODS: We collect longitudinal data to aid machine learning in accurately identifying patterns of mental disorder symptoms. We developed an app that collects voice, physiological, and activity data. Physiological and activity data are provided by a variety of off-the-shelf fitness trackers, that record steps, active minutes, duration of sleeping stages (rapid eye movement, deep, and light sleep), calories consumed, distance walked, heart rate, and speed. We also collect voice recordings of users reading specific texts and answering open-ended questions chosen randomly from a set of questions without repetition. Finally, the app collects users' answers to the Depression, Anxiety, and Stress Scale. The collected data from wearable devices and voice recordings will be used to train machine learning models to predict the levels of anxiety, stress, and depression in participants. RESULTS: The study is ongoing, and data collection will be completed by November 2023. We expect to recruit at least 50 participants attending 2 major universities (in Canada and Mexico) fluent in English or Spanish. The study will include participants aged between 18 and 35 years, with no communication disorders, acute neurological diseases, or history of brain damage. Data collection complied with ethical and privacy requirements. CONCLUSIONS: The study aims to advance personalized machine learning for mental health; generate a data set to predict Depression, Anxiety, and Stress Scale results; and deploy a framework for early detection of depression, anxiety, and stress. Our long-term goal is to develop a noninvasive and objective method for collecting mental health data and promptly detecting mental disorder symptoms. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/48210.

13.
Oncogenesis ; 12(1): 48, 2023 Oct 26.
Article En | MEDLINE | ID: mdl-37884500

Sustained chronic inflammation of the large intestine leads to tissue damage and repair, which is associated with an increased incidence of colitis-associated colorectal cancer (CAC). The genetic makeup of CAC is somewhat similar to sporadic colorectal carcinoma (sCRC), but there are differences in the sequence and timing of alterations in the carcinogenesis process. Several models have been developed to explain the development of CAC, particularly the "field cancerization" model, which proposes that chronic inflammation accelerates mutagenesis and selects for the clonal expansion of phenotypically normal, pro-tumorigenic cells. In contrast, the "Big Bang" model posits that tumorigenic clones with multiple driver gene mutations emerge spontaneously. The details of CAC tumorigenesis-and how they differ from sCRC-are not yet fully understood. In this Review, we discuss recent genetic, epigenetic, and environmental findings related to CAC pathogenesis in the past five years, with a focus on unbiased, high-resolution genetic profiling of non-dysplastic field cancerization in the context of inflammatory bowel disease (IBD).

14.
Mol Ecol ; 2023 Sep 16.
Article En | MEDLINE | ID: mdl-37715558

Spatial competition in the intertidal zones drives the community structure in marine benthic habitats. Organisms inhabiting these areas not only need to withstand fluctuations in temperature, water level, pH, and salinity but also need to compete for the best available space. Sponges are key members of the intertidal zones, and their life history processes (e.g. growth, reproduction, and regeneration) are affected by competition. Here, we used transcriptomics to investigate the effects of interspecific competition between the tetillid sponge Cinachyrella cf. cavernosa, the zoantharid Zoanthus sansibaricus and the macroalgae Dictyota ciliolata in the field. The analysis of differentially expressed genes showed that Z. sansibaricus was the more stressful competitor to C. cf. cavernosa, which showed an upregulation of cellular respiration under stress of competition. Similarly, an upregulation of energy metabolism, lipid metabolism and the heat-shock protein (HSP) 70 was also observed along with an increase in viral load and decreased ability to synthesize protein. A downregulation of purine and pyrimidine metabolism indicated a reduction in the physiological activities of the competing sponges. Moreover, a putative case of possible kleptocnidism, not previously reported in C. cf. cavernosa, was also observed. This study offers a glimpse into the inner workings of marine organisms competing for spatial resources using transcriptome data.

15.
J Gastrointest Surg ; 27(12): 3001-3013, 2023 Dec.
Article En | MEDLINE | ID: mdl-37550590

BACKGROUND: Lymphatic spread of intrahepatic cholangiocarcinoma (iCCA) is common and negatively impacts survival. However, the precise role of lymph node dissection (LND) in oncologic outcomes for patients with intrahepatic cholangiocarcinoma remains to be established. METHODS: Updated evidence on the preoperative diagnosis and prognostic value of lymph node metastasis is reviewed, as well as the potential benefit of LND in patients with iCCA. RESULTS: The ability to accurately determine nodal status for iCCA with current imaging modalities is equivocal. LND has prognostic value for both survival and disease recurrence. However, execution rates of LND are highly varied in the literature, ranging from 26.9 to 100%. At least 6 lymph nodes should be examined from nodal stations of the hepatoduodenal ligament and hepatic artery as well as based on the location of the primary tumor. Neoadjuvant therapies may be beneficial if lymph node metastases at diagnosis are suspected. Surgeons performing a minimally invasive approach should focus on increasing LND rates and harvesting ≥ 6 lymph nodes. Lymph node negativity is required in patients with iCCA being considered for liver transplantation under investigational protocols. CONCLUSION: Despite an upward trend in the LND rate, the reality is that only 10% of patients with iCCA receive an adequate LND. This review underscores the importance of routinely increasing the rate of adequate LND in these patients in order to achieve accurate staging, appropriately select patients for adjuvant therapy, and improve the prognosis of clinical outcomes. While prospective data is lacking, the therapeutic impact of LND remains unknown.


Bile Duct Neoplasms , Cholangiocarcinoma , Humans , Prospective Studies , Neoplasm Recurrence, Local/pathology , Lymph Node Excision/methods , Lymph Nodes/surgery , Lymph Nodes/pathology , Prognosis , Bile Ducts, Intrahepatic/surgery , Lymphatic Metastasis/pathology , Bile Duct Neoplasms/pathology , Neoplasm Staging , Retrospective Studies
16.
Epigenetics Chromatin ; 16(1): 29, 2023 Jul 06.
Article En | MEDLINE | ID: mdl-37415185

Super-enhancers are large, densely concentrated swaths of enhancers that regulate genes critical for cell identity. Tumorigenesis is accompanied by changes in the super-enhancer landscape. These aberrant super-enhancers commonly form to activate proto-oncogenes, or other genes upon which cancer cells depend, that initiate tumorigenesis, promote tumor proliferation, and increase the fitness of cancer cells to survive in the tumor microenvironment. These include well-recognized master regulators of proliferation in the setting of cancer, such as the transcription factor MYC which is under the control of numerous super-enhancers gained in cancer compared to normal tissues. This Review will cover the expanding cell-intrinsic and cell-extrinsic etiology of these super-enhancer changes in cancer, including somatic mutations, copy number variation, fusion events, extrachromosomal DNA, and 3D chromatin architecture, as well as those activated by inflammation, extra-cellular signaling, and the tumor microenvironment.


DNA Copy Number Variations , Neoplasms , Humans , Enhancer Elements, Genetic , Neoplasms/genetics , Transcription Factors/genetics , Carcinogenesis/genetics , Tumor Microenvironment
17.
Cell Rep ; 42(5): 112536, 2023 05 30.
Article En | MEDLINE | ID: mdl-37210723

Here, we show that the tumor suppressor phosphatase and tensin homolog deleted from chromosome 10 (PTEN) sensitizes cells to ferroptosis, an iron-dependent form of cell death, by restraining the expression and activity of the cystine/glutamate antiporter system Xc- (xCT). Loss of PTEN activates AKT kinase to inhibit GSK3ß, increasing NF-E2 p45-related factor 2 (NRF2) along with transcription of one of its known target genes encoding xCT. Elevated xCT in Pten-null mouse embryonic fibroblasts increases the flux of cystine transport and synthesis of glutathione, which enhances the steady-state levels of these metabolites. A pan-cancer analysis finds that loss of PTEN shows evidence of increased xCT, and PTEN-mutant cells are resistant to ferroptosis as a consequence of elevated xCT. These findings suggest that selection of PTEN mutation during tumor development may be due to its ability to confer resistance to ferroptosis in the setting of metabolic and oxidative stress that occurs during tumor initiation and progression.


Cystine , Ferroptosis , Animals , Mice , Cystine/metabolism , Proto-Oncogene Proteins c-akt/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Glycogen Synthase Kinase 3 beta/metabolism , Fibroblasts/metabolism
18.
J Pediatr ; 259: 113419, 2023 08.
Article En | MEDLINE | ID: mdl-37044372

OBJECTIVES: To evaluate implementation of rifamycin-based regimens (RBR) for pediatric tuberculosis infection (TBI) treatment among 3 provider settings in a high-incidence county. STUDY DESIGN: A multicenter, retrospective observational study was performed across 3 sites in Los Angeles County: an academic center (AC), a general pediatrics federally qualified health center (FQHC), and department of public health (DPH) tuberculosis clinics. Patients initiated on TBI treatment age 1 months to 17 years between 2018 and 2020 were included. RBRs were defined as regimens: 3 months of weekly rifapentine and isoniazid, 4 months of daily rifampin, and 3 months of daily isoniazid and rifampin. RESULTS: We included 424 patients: 51 from AC, 327 from DPH, and 46 from FQHC. RBR use nearly doubled during the study period (from 43% in 2018 to 82% in 2020; P < .001). FQHC had the shortest time to chest radiograph and treatment initiation; however, AC and DPH were 4 times as likely to prescribe an RBR compared to FQHC (95% CI, 2.1-7.8). AC and DPH had similar completion rates (74%) and were 2.6 times as likely to complete treatment compared to FQHC (95% CI, 1.4-4.9). CONCLUSIONS: The use of RBRs for pediatric TBI varies significantly by clinical setting but is improving over time. Strategies are needed to improve RBR uptake, standardize care, and increase treatment completion, particularly among general pediatricians.


Latent Tuberculosis , Pediatrics , Tuberculosis , Humans , Child , Infant , Rifampin/therapeutic use , Isoniazid/therapeutic use , Antitubercular Agents/therapeutic use , Tuberculosis/drug therapy , Drug Therapy, Combination
20.
Pigment Cell Melanoma Res ; 36(5): 407-415, 2023 09.
Article En | MEDLINE | ID: mdl-37086018

In melanoma, immune cell infiltration into the tumor is associated with better patient outcomes and response to immunotherapy. T-cell non-inflamed tumors (cold tumors) are associated with tumor cell-intrinsic Wnt/ß-catenin activation, and are typically resistant to anti-PD-1 alone or in combination with anti-CTLA-4 therapy. Reversal of the 'cold tumor' phenotype and identifying new effective immunotherapies are challenges. We sought to investigate the role of a newer immunotherapy agent, B7-H3, in this setting. RNA sequencing was used to identify co-targeting strategies upon B7-H3 inhibition in a well-defined preclinical melanoma model driven by ß-catenin. We found that immune checkpoint molecule B7-H3 confers a suppressive tumor microenvironment by modulating antiviral signals and innate immunity. B7-H3 inhibition led to an inflamed microenvironment, up-regulation of CD47/SIRPa signaling, and together with blockade of the macrophage checkpoint CD47 resulted in additive antitumor responses. We found that the antitumor effects of the B7-H3/CD47 antibody combination were dependent on cytokine signaling pathways (CCR5/CCL5 and IL4).


Melanoma , Humans , B7-H1 Antigen , beta Catenin , CD47 Antigen , Immunosuppression Therapy , Immunotherapy/methods , Melanoma/therapy , Tumor Microenvironment
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