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1.
J Arthroplasty ; 2024 May 24.
Article in English | MEDLINE | ID: mdl-38797448

ABSTRACT

INTRODUCTION: Venous thromboembolism (VTE) poses a major clinical concern due to its life-threatening nature, and obese and morbidly obese patients are thought to be at an increased risk for VTE. The aims of this study were twofold; first, to explore VTE rates in patients who have a body mass index > 40 undergoing primary and revision total joint arthroplasty (TJA), and second, to investigate aspirin (ASA) efficacy and safety. METHODS: We identified all patients (n = 4,672) who had a BMI > 40 who underwent primary and revision TJA from 2016 to 2022 at a single academic tertiary care center. Patients were stratified by BMI groups: 40 to 44.9 (n = 3,462), 45 to 49.9 (n = 935), and 50+ (n = 275). The primary outcome was any venous thromboembolism (VTE) event within 90 days postoperatively. The secondary outcome consisted of wound complications within 90 days postoperatively. RESULTS: The total VTE rate was 0.4% (n = 21) and did not differ statistically between the BMI groups (0.4 versus 0.4 versus 0.7%, P = 0.669). The VTEs consisted of six deep venous thromboses (DVT), fourteen pulmonary embolisms (PE), and one concomitant DVT and PE. The VTE rates were not statistically different between patients who received aspirin 325 mg 0.5% (n = 9), aspirin 81 mg 0.2% (n = 1), aspirin + anticoagulant 0.5% (n = 6), and anticoagulant alone 0.4% (n = 5) (P = 0.954). In addition, wound complications did not differ significantly between patients who received ASA 325 mg, ASA 81mg, ASA + anticoagulant, or anticoagulant alone (1.6 versus 1.0 versus 1.8 versus 1.1%, P = 0.351). CONCLUSION: The use of aspirin 325 mg and 81 mg was found to have similar VTE rates as aspirin + anticoagulants and anticoagulants alone, with no significant increase in wound complications. In patients who have a BMI > 40, the use of aspirin is a safe option for VTE prophylaxis and should be prescribed in the context of the patient who has other risk factors for VTE.

2.
Antimicrob Agents Chemother ; : e0042024, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38780261

ABSTRACT

Capsid assembly mediated by hepatitis B virus (HBV) core protein (HBc) is an essential part of the HBV replication cycle, which is the target for different classes of capsid assembly modulators (CAMs). While both CAM-A ("aberrant") and CAM-E ("empty") disrupt nucleocapsid assembly and reduce extracellular HBV DNA, CAM-As can also reduce extracellular HBV surface antigen (HBsAg) by triggering apoptosis of HBV-infected cells in preclinical mouse models. However, there have not been substantial HBsAg declines in chronic hepatitis B (CHB) patients treated with CAM-As to date. To investigate this disconnect, we characterized the antiviral activity of tool CAM compounds in HBV-infected primary human hepatocytes (PHHs), as well as in HBV-infected human liver chimeric mice and mice transduced with adeno-associated virus-HBV. Mechanistic studies in HBV-infected PHH revealed that CAM-A, but not CAM-E, induced a dose-dependent aggregation of HBc in the nucleus which is negatively regulated by the ubiquitin-binding protein p62. We confirmed that CAM-A, but not CAM-E, induced HBc-positive cell death in both mouse models via induction of apoptotic and inflammatory pathways and demonstrated that the degree of HBV-positive cell loss was positively correlated with intrahepatic HBc levels. Importantly, we determined that there is a significantly lower level of HBc per hepatocyte in CHB patient liver biopsies than in either of the HBV mouse models. Taken together, these data confirm that CAM-As have a unique secondary mechanism with the potential to kill HBc-positive hepatocytes. However, this secondary mechanism appears to require higher intrahepatic HBc levels than is typically observed in CHB patients, thereby limiting the therapeutic potential.

3.
J Arthroplasty ; 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38677347

ABSTRACT

BACKGROUND: Cefazolin is the standard of care for perioperative antibiotic prophylaxis in total joint arthroplasty (TJA) in the United States. The potential allergic cross-reactivity between cefazolin and penicillin causes uncertainty regarding optimal antibiotic choice in patients who have a reported penicillin allergy (rPCNA). The purpose of this study was to determine the safety of perioperative cefazolin in PCNA patients undergoing primary TJA. METHODS: We identified all patients (n = 49,842) undergoing primary total hip arthroplasty (n = 25,659) or total knee arthroplasty (n = 24,183) from 2016 to 2022 who received perioperative intravenous antibiotic prophylaxis. Patients who had an rPCNA (n = 5,508) who received cefazolin (n = 4,938, 89.7%) were compared to rPCNA patients who did not (n = 570, 10.3%), and to patients who did not have an rPCNA (n = 43,359). The primary outcome was the rate of allergic reactions within 72 hours postoperatively. Secondary outcomes included the rates of superficial infections, deep infections, and Clostridioides difficile infections within 90 days. RESULTS: The rate of allergic reactions was 0.1% (n = 5) in rPCNA patients who received cefazolin, compared to 0.2% (n = 1) in rPCNA patients who did not (P = .48) and 0.02% (n = 11) in patients who have no rPCNA (P = .02). Allergic reactions were mild in all 5 rPCNA patients who received cefazolin and were characterized by cutaneous symptoms (n = 4) or dyspnea in the absence of respiratory distress (n = 1) that resolved promptly with antibiotic discontinuation and administration of antihistamines and/or corticosteroids. We observed no differences in the rates of superficial infections (0.1 versus 0.2%, P = .58), deep infections (0.3 versus 0.4%, P = .68), or C difficile infections (0.04% versus 0%, P = .99) within 90 days in rPCNA patients who received cefazolin versus alternative perioperative antibiotics. CONCLUSIONS: In this series of more than 5,500 patients who had an rPCNA undergoing primary TJA, perioperative prophylaxis with cefazolin resulted in a 0.1% incidence of allergic reactions that were clinically indolent. Cefazolin can be safely administered to most patients, independent of rPCNA severity. LEVEL OF EVIDENCE: III.

4.
Am J Otolaryngol ; 45(4): 104278, 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38604100

ABSTRACT

BACKGROUND: Merkel cell carcinoma (MCC) is an aggressive and rare neuroendocrine tumor, accounting for less than 1% of skin cancers. Metastasis primarily manifests in the cervical lymph nodes but rarely affect the thyroid. METHODS: We report a case of primary head and neck cutaneous MCC with metastasis to the thyroid gland. A review of the literature of MCC with thyroid metastasis was conducted. RESULTS: We identified five cases of MCC with thyroid metastasis. Primary sites included the distal upper and lower extremities, axilla, buttock, and groin. Treatment courses varied including thyroidectomy, immunotherapy, and expectant palliative measures. Time from initial diagnosis to thyroid metastasis ranged from four months to four years. Tissue diagnosis was achieved in 5 of 6 cases. CONCLUSIONS: MCC with thyroid metastasis is rare and likely represents aggressive disease. Despite advances in treatment and surveillance, outcomes for MCC remain poor. Ongoing research may establish predictors for treatment response.

5.
J Toxicol ; 2024: 3769933, 2024.
Article in English | MEDLINE | ID: mdl-38633362

ABSTRACT

Although herbal drugs are often considered safe for consumption, there is increasing evidence that some can generate undesirable health effects. However, polyphenols found in certain plants have been shown to provide a range of benefits for human health. In previous work, a standardized and quantified extract (P2Et) obtained from Caesalpinia spinosa (Dividivi) plant showed promising antioxidant, immunomodulatory, and anti-inflammatory properties in animal models of cancer and COVID-19 patients. The extract has also been subjected to genotoxicity, mutagenicity, and 28-day oral chronic toxicity evaluations, demonstrating a good safety profile. To advance preclinical and clinical development, further acute and chronic toxicity evaluations of the P2Et extract were performed. Acute toxicity tests were performed orally in Wistar rats at a dose of 2000 mg/kg, indicating that the lethal dose 50% (LD50) value exceeded 2000 mg/kg and classifying the P2Et extract as category 5 according to the Globally Harmonized System of Classification (GHS). In this work, chronic toxicity tests were conducted for 180 days on Wistar rats and New Zealand rabbits at a dose of 1000 mg/kg under Good Laboratory Practice (GLP) conditions. No weight loss or alterations in biochemical and hematological parameters associated with treatment were observed in the animals, suggesting the absence of toxicity in the assessed parameters. These results indicate that the P2Et extract is safe for oral administration at doses up to 1000 mg/kg body weight over a six-month period.

6.
ACS Chem Biol ; 19(2): 407-418, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38301282

ABSTRACT

Mixed lineage kinase domain-like (MLKL) is a key signaling protein of necroptosis. Upon activation by phosphorylation, MLKL translocates to the plasma membrane and induces membrane permeabilization, which contributes to the necroptosis-associated inflammation. Membrane binding of MLKL is initially initiated by electrostatic interactions between the protein and membrane phospholipids. We previously showed that MLKL and its phosphorylated form (pMLKL) are S-acylated during necroptosis. Here, we characterize the acylation sites of MLKL and identify multiple cysteines that can undergo acylation with an interesting promiscuity at play. Our results show that MLKL and pMLKL undergo acylation at a single cysteine, with C184, C269, and C286 as possible acylation sites. Using all-atom molecular dynamic simulations, we identify differences that the acylation of MLKL causes at the protein and membrane levels. Through investigations of the S-palmitoyltransferases that might acylate pMLKL in necroptosis, we showed that zDHHC21 activity has the strongest effect on pMLKL acylation, inactivation of which profoundly reduced the pMLKL levels in cells and improved membrane integrity. These results suggest that blocking the acylation of pMLKL destabilizes the protein at the membrane interface and causes its degradation, ameliorating the necroptotic activity. At a broader level, our findings shed light on the effect of S-acylation on MLKL functioning in necroptosis and MLKL-membrane interactions mediated by its acylation.


Subject(s)
Necroptosis , Protein Kinases , Protein Kinases/metabolism , Phosphorylation , Cell Membrane/metabolism , Apoptosis
7.
Nat Commun ; 15(1): 267, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38267429

ABSTRACT

Ultrafast photoinduced phase transitions at room temperature, driven by a single laser shot and persisting long after stimuli, represent emerging routes for ultrafast control over materials' properties. Time-resolved studies provide fundamental mechanistic insight into far-from-equilibrium electronic and structural dynamics. Here we study the photoinduced phase transformation of the Rb0.94Mn0.94Co0.06[Fe(CN)6]0.98 material, designed to exhibit a 75 K wide thermal hysteresis around room temperature between MnIIIFeII tetragonal and MnIIFeIII cubic phases. We developed a specific powder sample streaming technique to monitor by ultrafast X-ray diffraction the structural and symmetry changes. We show that the photoinduced polarons expand the lattice, while the tetragonal-to-cubic photoinduced phase transition occurs within 100 ps above threshold fluence. These results are rationalized within the framework of the Landau theory of phase transition as an elastically-driven and cooperative process. We foresee broad applications of the streaming powder technique to study non-reversible and ultrafast dynamics.

8.
Am J Physiol Endocrinol Metab ; 326(3): E207-E214, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38170165

ABSTRACT

Mitochondrial open reading frame of the 12S ribosomal RNA type-c (MOTS-c), a mitochondrial microprotein, has been described as a novel regulator of glucose and lipid metabolism. In addition to its role as a metabolic regulator, MOTS-c prevents skeletal muscle atrophy in high fat-fed mice. Here, we examined the preventive effect of MOTS-c on skeletal muscle mass, using an immobilization-induced muscle atrophy model, and explored its underlying mechanisms. Male C57BL/6J mice (10 wk old) were randomly assigned to one of the three experimental groups: nonimmobilization control group (sterilized water injection), immobilization control group (sterilized water injection), and immobilization and MOTS-c-treated group (15 mg/kg/day MOTS-c injection). We used casting tape for the immobilization experiment. After 8 days of the experimental period, skeletal muscle samples were collected and used for Western blotting, RNA sequencing, and lipid and collagen assays. Immobilization reduced ∼15% of muscle mass, whereas MOTS-c treatment attenuated muscle loss, with only a 5% reduction. MOTS-c treatment also normalized phospho-AKT, phospho-FOXO1, and phospho-FOXO3a expression levels and reduced circulating inflammatory cytokines, such as interleukin-1b (IL-1ß), interleukin-6 (IL-6), chemokine C-X-C motif ligand 1 (CXCL1), and monocyte chemoattractant protein 1 (MCP-1), in immobilized mice. Unbiased RNA sequencing and its downstream analyses demonstrated that MOTS-c modified adipogenesis-modulating gene expression within the peroxisome proliferator-activated receptor (PPAR) pathway. Supporting this observation, muscle fatty acid levels were lower in the MOTS-c-treated group than in the casted control mice. These results suggest that MOTS-c treatment inhibits skeletal muscle lipid infiltration by regulating adipogenesis-related genes and prevents immobilization-induced muscle atrophy.NEW & NOTEWORTHY MOTS-c, a mitochondrial microprotein, attenuates immobilization-induced skeletal muscle atrophy. MOTS-c treatment improves systemic inflammation and skeletal muscle AKT/FOXOs signaling pathways. Furthermore, unbiased RNA sequencing and subsequent assays revealed that MOTS-c prevents lipid infiltration in skeletal muscle. Since lipid accumulation is one of the common pathologies among other skeletal muscle atrophies induced by aging, obesity, cancer cachexia, and denervation, MOTS-c treatment could be effective in other muscle atrophy models as well.


Subject(s)
Micropeptides , Proto-Oncogene Proteins c-akt , Male , Mice , Animals , Proto-Oncogene Proteins c-akt/metabolism , Mice, Inbred C57BL , Muscular Atrophy/etiology , Muscular Atrophy/prevention & control , Muscle, Skeletal/metabolism , Transcription Factors/metabolism , Water , Lipids
9.
Mol Psychiatry ; 29(2): 505-517, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38167865

ABSTRACT

Mitochondrial DNA single nucleotide polymorphisms (mtSNPs) have been associated with a reduced risk of developing Parkinson's disease (PD), yet the underlying mechanisms remain elusive. In this study, we investigate the functional role of a PD-associated mtSNP that impacts the mitochondrial-derived peptide (MDP) Small Humanin-like Peptide 2 (SHLP2). We identify m.2158 T > C, a mtSNP associated with reduced PD risk, within the small open reading frame encoding SHLP2. This mtSNP results in an alternative form of SHLP2 (lysine 4 replaced with arginine; K4R). Using targeted mass spectrometry, we detect specific tryptic fragments of SHLP2 in neuronal cells and demonstrate its binding to mitochondrial complex 1. Notably, we observe that the K4R variant, associated with reduced PD risk, exhibits increased stability compared to WT SHLP2. Additionally, both WT and K4R SHLP2 show enhanced protection against mitochondrial dysfunction in in vitro experiments and confer protection against a PD-inducing toxin, a mitochondrial complex 1 inhibitor, in a mouse model. This study sheds light on the functional consequences of the m.2158 T > C mtSNP on SHLP2 and provides insights into the potential mechanisms by which this mtSNP may reduce the risk of PD.


Subject(s)
Mitochondria , Parkinson Disease , Polymorphism, Single Nucleotide , Parkinson Disease/genetics , Parkinson Disease/metabolism , Animals , Mice , Humans , Polymorphism, Single Nucleotide/genetics , Mitochondria/metabolism , DNA, Mitochondrial/genetics , Protective Factors , Mice, Inbred C57BL , Neurons/metabolism , Disease Models, Animal , Male , Electron Transport Complex I/metabolism , Electron Transport Complex I/genetics , Peptides/genetics , Peptides/metabolism , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Intracellular Signaling Peptides and Proteins
10.
Clin Cancer Res ; 30(7): 1409-1421, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-37939112

ABSTRACT

PURPOSE: Our goal was to demonstrate that lymphatic drainage fluid (lymph) has improved sensitivity in quantifying postoperative minimal residual disease (MRD) in locally advanced human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) compared with plasma, and leverage this novel biofluid for patient risk stratification. EXPERIMENTAL DESIGN: We prospectively collected lymph samples from neck drains of 106 patients with HPV (+) OPSCC, along with 67 matched plasma samples, 24 hours after surgery. PCR and next-generation sequencing were used to quantify cancer-associated cell-free HPV (cf-HPV) and tumor-informed variants in lymph and plasma. Next, lymph cf-HPV and variants were compared with TNM stage, extranodal extension (ENE), and composite definitions of high-risk pathology. We then created a machine learning model, informed by lymph MRD and clinicopathologic features, to compare with progression-free survival (PFS). RESULTS: Postoperative lymph was enriched with cf-HPV compared with plasma (P < 0.0001) and correlated with pN2 stage (P = 0.003), ENE (P < 0.0001), and trial-defined pathologic risk criteria (mean AUC = 0.78). In addition, the lymph mutation number and variant allele frequency were higher in pN2 ENE (+) necks than in pN1 ENE (+) (P = 0.03, P = 0.02) or pN0-N1 ENE (-) (P = 0.04, P = 0.03, respectively). The lymph MRD-informed risk model demonstrated inferior PFS in high-risk patients (AUC = 0.96, P < 0.0001). CONCLUSIONS: Variant and cf-HPV quantification, performed in 24-hour postoperative lymph samples, reflects single- and multifeature high-risk pathologic criteria. Incorporating lymphatic MRD and clinicopathologic feature analysis can stratify PFS early after surgery in patients with HPV (+) head and neck cancer. See related commentary by Shannon and Iyer, p. 1223.


Subject(s)
Head and Neck Neoplasms , Oropharyngeal Neoplasms , Papillomavirus Infections , Humans , Human Papillomavirus Viruses , Papillomavirus Infections/complications , Papillomavirus Infections/diagnosis , Papillomavirus Infections/surgery , Neoplasm, Residual/pathology , Prognosis , Neoplasm Staging , Oropharyngeal Neoplasms/diagnosis , Oropharyngeal Neoplasms/surgery , Oropharyngeal Neoplasms/pathology , Head and Neck Neoplasms/pathology , Squamous Cell Carcinoma of Head and Neck/diagnosis , Squamous Cell Carcinoma of Head and Neck/genetics , Squamous Cell Carcinoma of Head and Neck/surgery , Retrospective Studies
11.
Article in English | MEDLINE | ID: mdl-38092990

ABSTRACT

Major depressive disorder (MDD) and type 2 diabetes (T2D) are complex disorders whose comorbidity can be due to hypercortisolism and may be explained by dysfunction of the corticotropin-releasing hormone receptor 1 (CRHR1) and cortisol feedback within the hypothalamic-pituitary-adrenal axis (HPA axis). To investigate the role of the CRHR1 gene in familial T2D, MDD, and MDD-T2D comorbidity, we tested 152 CRHR1 single-nucleotide-polymorphisms (SNPs), via 2-point parametric linkage and linkage disequilibrium (LD; i.e., association) analyses using 4 models, in 212 peninsular families with T2D and MDD. We detected linkage/LD/association to/with MDD and T2D with 122 (116 novel) SNPs. MDD and T2D had 4 and 3 disorder-specific novel risk LD blocks, respectively, whose risk variants reciprocally confirm one another. Comorbidity was conferred by 3 novel independent SNPs. In silico analyses reported novel functional changes, including the binding site of glucocorticoid receptor-alpha [GR-α] on CRHR1 for transcription regulation. This is the first report of CRHR1 pleiotropic linkage/LD/association with peninsular familial MDD and T2D. CRHR1 contribution to MDD is stronger than to T2D and may antecede T2D onset. Our findings suggest a new molecular-based clinical entity of MDD-T2D and should be replicated in other ethnic groups.

12.
J Clin Med ; 12(24)2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38137584

ABSTRACT

The aim of this study was to assess the shear wave velocity by LUS elastography (SWE2D) for the evaluation of superficial lung stiffness after COVID-19 pneumonia, according to "fibrosis-like" signs found by Computed Tomography (CT), considering the respiratory function. Seventy-nine adults participated in the study 42 to 353 days from symptom onset. Paired evaluations (SWE2D and CT) were performed along with the assessment of arterial blood gases and spirometry, three times with 100 days in between. During the follow-up and within each evaluation, the SWE2D velocity changed over time (MANOVA, p < 0.05) according to the extent of "fibrosis-like" CT signs by lung lobe (ANOVA, p < 0.05). The variability of the SWE2D velocity was consistently related to the first-second forced expiratory volume and the forced vital capacity (MANCOVA, p < 0.05), which changed over time with no change in blood gases. Covariance was also observed with age and patients' body mass index, the time from symptom onset until hospital admission, and the history of diabetes in those who required intensive care during the acute phase (MANCOVA, p < 0.05). After COVID-19 pneumonia, SWE2D velocity can be related to the extent and regression of "fibrotic-like" involvement of the lung lobes, and it could be a complementary tool in the follow-up after COVID-19 pneumonia.

13.
Front Mol Biosci ; 10: 1235160, 2023.
Article in English | MEDLINE | ID: mdl-38028534

ABSTRACT

Acute leukemias (AL) are aggressive neoplasms with high mortality rates. Metabolomics and oxidative status have emerged as important tools to identify new biomarkers with clinical utility. To identify the metabolic differences between healthy individuals (HI) and patients with AL, a multiplatform untargeted metabolomic and lipidomic approach was conducted using liquid and gas chromatography coupled with quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS or GC-QTOF-MS). Additionally, the total antioxidant capacity (TAC) was measured. A total of 20 peripheral blood plasma samples were obtained from patients with AL and 18 samples from HI. Our analysis revealed 135 differentially altered metabolites in the patients belonging to 12 chemical classes; likewise, the metabolic pathways of glycerolipids and sphingolipids were the most affected in the patients. A decrease in the TAC of the patients with respect to the HI was evident. This study conducted with a cohort of Colombian patients is consistent with observations from other research studies that suggest dysregulation of lipid compounds. Furthermore, metabolic differences between patients and HI appear to be independent of lifestyle, race, or geographic location, providing valuable information for future advancements in understanding the disease and developing more global therapies.

14.
J Homosex ; : 1-22, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-37976200

ABSTRACT

The representation of gays and lesbians on Chilean television has increased steadily over the last decades. This paper offers an analysis of the role these images had in the processes of sexual identification of a sample of 25 members of the audience who identify as gays or lesbians. Through a thematic analysis of semi-structured interviews, it is shown that the respondents believed that the televisual representations of homosexuality have contributed to further marginalize gay and lesbian lives. This strengthened damaging feelings that fed into a sense of shame that was originating from multiple institutions and texts, thus complicating their processes of self-recognition and self-acceptance during their childhood and adolescence. Taking examples of how participants described their relationship with these representations and the ways in which they circulated socially, it is argued that they could only articulate their identification as gays or lesbians by disassociating themselves from these images and establishing a clear difference in regard to them. This was in a process in which several other informational and experiential opportunities came into play, which allowed them to resignify the categories gay/lesbian and lead less conflictive processes of identification.

15.
Front Physiol ; 14: 1286808, 2023.
Article in English | MEDLINE | ID: mdl-38033343

ABSTRACT

CaVγ2 (Stargazin or TARPγ2) is a protein expressed in various types of neurons whose function was initially associated with a decrease in the functional expression of voltage-gated presynaptic Ca2+ channels (CaV) and which is now known to promote the trafficking of the postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPAR) towards the cell membrane. Alterations in CaVγ2 expression has been associated with several neurological disorders, such as absence epilepsy. However, its regulation at the transcriptional level has not been intensively addressed. It has been reported that the promoter of the Cacng2 gene, encoding the rat CaVγ2, is bidirectional and regulates the transcription of a long non-coding RNA (lncRNA) in the antisense direction. Here, we investigate the proximal promoter region of the human CACNG2 gene in the antisense direction and show that this region includes two functional cAMP response elements that regulate the expression of a lncRNA called CACNG2-DT. The activity of these sites is significantly enhanced by forskolin, an adenylate cyclase activator, and inhibited by H89, a protein kinase A (PKA) antagonist. Therefore, this regulatory mechanism implies the activation of G protein-coupled receptors and downstream phosphorylation. Interestingly, we also found that the expression of CACNG2-DT may increase the levels of the CaVγ2 subunit. Together, these data provide novel information on the organization of the human CACNG2-DT gene promoter, describe modulatory domains and mechanisms that can mediate various regulatory inputs, and provide initial information on the molecular mechanisms that regulate the functional expression of the CaVγ2 protein.

16.
Nature ; 624(7991): 433-441, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38030726

ABSTRACT

FOXP3 is a transcription factor that is essential for the development of regulatory T cells, a branch of T cells that suppress excessive inflammation and autoimmunity1-5. However, the molecular mechanisms of FOXP3 remain unclear. Here we here show that FOXP3 uses the forkhead domain-a DNA-binding domain that is commonly thought to function as a monomer or dimer-to form a higher-order multimer after binding to TnG repeat microsatellites. The cryo-electron microscopy structure of FOXP3 in a complex with T3G repeats reveals a ladder-like architecture, whereby two double-stranded DNA molecules form the two 'side rails' bridged by five pairs of FOXP3 molecules, with each pair forming a 'rung'. Each FOXP3 subunit occupies TGTTTGT within the repeats in a manner that is indistinguishable from that of FOXP3 bound to the forkhead consensus motif (TGTTTAC). Mutations in the intra-rung interface impair TnG repeat recognition, DNA bridging and the cellular functions of FOXP3, all without affecting binding to the forkhead consensus motif. FOXP3 can tolerate variable inter-rung spacings, explaining its broad specificity for TnG-repeat-like sequences in vivo and in vitro. Both FOXP3 orthologues and paralogues show similar TnG repeat recognition and DNA bridging. These findings therefore reveal a mode of DNA recognition that involves transcription factor homomultimerization and DNA bridging, and further implicates microsatellites in transcriptional regulation and diseases.


Subject(s)
DNA , Forkhead Transcription Factors , Microsatellite Repeats , Base Sequence , Consensus Sequence , Cryoelectron Microscopy , DNA/chemistry , DNA/genetics , DNA/metabolism , DNA/ultrastructure , Forkhead Transcription Factors/chemistry , Forkhead Transcription Factors/metabolism , Forkhead Transcription Factors/ultrastructure , Microsatellite Repeats/genetics , Mutation , Nucleotide Motifs , Protein Domains , Protein Multimerization , T-Lymphocytes, Regulatory/metabolism
17.
Toxicol Rep ; 11: 396-404, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37955035

ABSTRACT

The genus Passiflora (Passifloraceae) comprises about 500 species. The Passiflora edulis stands out because of its economic and medicinal importance. It is widely planted in tropical and subtropical regions worldwide, especially in South America, the Caribbean, South Africa, and Asia. The aqueous extract of Passiflora edulis Sims f. edulis (Gulupa) leaves is used in traditional medicine for its soothing and tranquilizing effects on the central nervous system. Therefore, evaluating its safety for human use is a fundamental requirement to continue the development of new therapies within the framework of regulatory, preclinical, and clinical guidelines. Here, the sub-acute toxicity study was conducted following the Organization for Economic Cooperation and Development (OECD) guideline 407 for 28 days in Wistar albino rats. The study showed that 1000 mg/kg/day of the aqueous extract in 10 adult Wistar rats (five males and five females) was well tolerated. The hematological results are at normal levels. However, monocytopenia and eosinopenia were observed with a significant difference (P < 0,05) for both male and female rats treated with the aqueous extract of Passiflora edulis. The results show that liver and kidney function profiles were conserved. However, an increase in ALT is observed with significant differences between male and female rats treated with the extract compared to the controls. Study findings were limited to non-adverse histopathological results of a slightly increased incidence of focal periportal lymphocytic infiltrate in the liver and focal corticomedullary nephrocalcinosis in the kidney compared to control. Therefore, the aqueous extract of Passiflora edulis has a good safety profile in oral administration, was well tolerated, and did not cause any lethality or adverse effects in the sub-acute toxicity study in male and female rats. The NOAEL (no observed adverse effect level) for the 28-day subacute toxicity study was considered to be 1000 mg/kg.

18.
bioRxiv ; 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37986949

ABSTRACT

FoxP3 is a transcription factor (TF) essential for development of regulatory T cells (Tregs), a branch of T cells that suppress excessive inflammation and autoimmunity 1-5 . Molecular mechanisms of FoxP3, however, remain elusive. We here show that FoxP3 utilizes the Forkhead domain--a DNA binding domain (DBD) that is commonly thought to function as a monomer or dimer--to form a higher-order multimer upon binding to T n G repeat microsatellites. A cryo-electron microscopy structure of FoxP3 in complex with T 3 G repeats reveals a ladder-like architecture, where two double-stranded DNA molecules form the two "side rails" bridged by five pairs of FoxP3 molecules, with each pair forming a "rung". Each FoxP3 subunit occupies TGTTTGT within the repeats in the manner indistinguishable from that of FoxP3 bound to the Forkhead consensus motif (FKHM; TGTTTAC). Mutations in the "intra-rung" interface impair T n G repeat recognition, DNA bridging and cellular functions of FoxP3, all without affecting FKHM binding. FoxP3 can tolerate variable "inter-rung" spacings, explaining its broad specificity for T n G repeat-like sequences in vivo and in vitro . Both FoxP3 orthologs and paralogs show similar T n G repeat recognition and DNA bridging. These findings thus reveal a new mode of DNA recognition that involves TF homo-multimerization and DNA bridging, and further implicates microsatellites in transcriptional regulation and diseases.

19.
Rev Med Inst Mex Seguro Soc ; 61(Suppl 3): S492-S496, 2023 Oct 02.
Article in Spanish | MEDLINE | ID: mdl-37935013

ABSTRACT

Background: Fusarium infection in the central nervous system is a rare pathology generally reported in patients with hematological malignancies. Clincal case: A patient with Fusarium meningoencephalitis during the late postpartum period is presented. The patient's main symptom was holocranial headache with poor response to analgesics, adding dysarthria and blurred vision. Initially, it was classified as aseptic meningitis due to the absence of bacterial isolation, however, 8 weeks after the onset of the symptoms, Fusarium development was obtained in cerebrospinal fluid cultures. Targeted treatment with liposomal amphotericin and voriconazole was established, with partial improvement at first; however, at 16 weeks from the onset of the clinical picture, the patient presented sudden deterioration of alertness, an ischemic area was found in the occipital lobe by imaging study, which quickly led the patient to a fatal outcome. Conclusion: Despite the fact that in recent years Fusarium spp infection has been detected more frequently in the population, the treatment is still not well established, making management of the Central Nervous System a challenge.


Introducción: la infección por Fusarium en el sistema nervioso central es una patología rara, reportada generalmente en pacientes con neoplasias hematológicas. Caso clínico: se presenta una paciente con meningoencefalitis por Fusarium durante el periodo de puerperio tardío. El síntoma principal de la paciente fue cefalea holocraneana con baja respuesta a analgésicos, agregándose disartria y visión borrosa. De manera inicial, se catalogó como meningitis aséptica por ausencia de aislamiento bacteriano, no obstante, a las 8 semanas posterior al inicio del cuadro se obtuvo desarrollo de Fusarium en los cultivos de líquido cefalorraquídeo. Se estableció tratamiento dirigido con anfotericina liposomal y voriconazol, con mejoría parcial en un inicio; sin embargo, la paciente a las 16 semanas desde el inicio del cuadro clínico presentó deterioro súbito del estado de alerta, se evidenció zona isquémica en el lóbulo occipital por estudio de imagen, lo que rápidamente llevó a la paciente a un desenlace fatal. Conclusión: a pesar de que en los últimos años la infección por Fusarium spp se ha detectado con mayor frecuencia en la población, el tratamiento aún no se encuentra bien establecido ocasionando que sea un reto el manejo en Sistema Nervioso Central.


Subject(s)
Fusarium , Meningoencephalitis , Female , Humans , Antifungal Agents/therapeutic use , Voriconazole/therapeutic use , Meningoencephalitis/diagnosis , Meningoencephalitis/drug therapy
20.
BMC Complement Med Ther ; 23(1): 309, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37670337

ABSTRACT

BACKGROUND: Chemotherapy in breast cancer is effective but can generate significant toxicity and lead to tumor resistance. Joint treatment with standardized plant extracts can be an alternative to improve the response and allow an effective activation of the antitumor immune response that favors recovery in the short and long term. The P2Et extract of Caesalpinia spinosa presents antitumor activity in cells and animal models of breast cancer, improves the tumor microenvironment, and induces activation of the specific immune response against the tumor and is synergistic when used together with anthracyclines, which makes it a good candidate for evaluation in patients. METHODS: Conducted at a single center, this phase II study is a randomized, double-blind, placebo-controlled trial aimed at assessing the safety and efficacy of P2Et extract in patients diagnosed with stage II and III breast cancer, who are eligible for neoadjuvant treatment. The study aims to determine the safety profile at the previously established optimal biological dose from phase I trial while investigating various efficacy outcomes. These outcomes include improvements in quality of life, immunomodulation, metabolic profile, microbiome, as well as clinical indicators such as tumor reduction, disease-free survival, and pathological response, assessed at different stages of the treatment regimen. DISCUSSION: Treatment with the P2Et extract in breast cancer patients is hypothesized to enhance overall well-being, positively influencing their quality of life, while also triggering an antitumor immune response and enhancing immune infiltration. These combined effects have the potential to contribute to improved long-term survival outcomes for patients receiving the phytomedicine alongside neoadjuvant chemotherapy treatment. TRIAL REGISTRATION: This trial was registered in the US National Library of Medicine with identifier NCT05007444. First Registered August 16th, 2021. Last Updated: August 9th, 2022.


Subject(s)
Caesalpinia , Neoplasms , United States , Animals , Quality of Life , Cyclic S-Oxides , Morpholines , Randomized Controlled Trials as Topic , Clinical Trials, Phase II as Topic , Clinical Trials, Veterinary as Topic
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