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1.
Nature ; 603(7903): 949-956, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35322233

RESUMEN

Membrane fusion triggered by Ca2+ is orchestrated by a conserved set of proteins to mediate synaptic neurotransmitter release, mucin secretion and other regulated exocytic processes1-4. For neurotransmitter release, the Ca2+ sensitivity is introduced by interactions between the Ca2+ sensor synaptotagmin and the SNARE complex5, and sequence conservation and functional studies suggest that this mechanism is also conserved for mucin secretion6. Disruption of Ca2+-triggered membrane fusion by a pharmacological agent would have therapeutic value for mucus hypersecretion as it is the major cause of airway obstruction in the pathophysiology of respiratory viral infection, asthma, chronic obstructive pulmonary disease and cystic fibrosis7-11. Here we designed a hydrocarbon-stapled peptide that specifically disrupts Ca2+-triggered membrane fusion by interfering with the so-called primary interface between the neuronal SNARE complex and the Ca2+-binding C2B domain of synaptotagmin-1. In reconstituted systems with these neuronal synaptic proteins or with their airway homologues syntaxin-3, SNAP-23, VAMP8, synaptotagmin-2, along with Munc13-2 and Munc18-2, the stapled peptide strongly suppressed Ca2+-triggered fusion at physiological Ca2+ concentrations. Conjugation of cell-penetrating peptides to the stapled peptide resulted in efficient delivery into cultured human airway epithelial cells and mouse airway epithelium, where it markedly and specifically reduced stimulated mucin secretion in both systems, and substantially attenuated mucus occlusion of mouse airways. Taken together, peptides that disrupt Ca2+-triggered membrane fusion may enable the therapeutic modulation of mucin secretory pathways.


Asunto(s)
Calcio , Hidrocarburos , Fusión de Membrana , Mucinas , Proteínas SNARE , Animales , Calcio/metabolismo , Hidrocarburos/química , Fusión de Membrana/fisiología , Ratones , Mucinas/metabolismo , Neurotransmisores/metabolismo , Péptidos/farmacología , Mucosa Respiratoria , Proteínas SNARE/metabolismo
2.
Genome Res ; 32(7): 1328-1342, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34162697

RESUMEN

Broad domains of H3K4 methylation have been associated with consistent expression of tissue-specific, cell identity, and tumor suppressor genes. Here, we identified broad domain-associated genes in healthy human thymic T cell populations and a collection of T cell acute lymphoblastic leukemia (T-ALL) primary samples and cell lines. We found that broad domains are highly dynamic throughout T cell differentiation, and their varying breadth allows the distinction between normal and neoplastic cells. Although broad domains preferentially associate with cell identity and tumor suppressor genes in normal thymocytes, they flag key oncogenes in T-ALL samples. Moreover, the expression of broad domain-associated genes, both coding and noncoding, is frequently deregulated in T-ALL. Using two distinct leukemic models, we showed that the ectopic expression of T-ALL oncogenic transcription factor preferentially impacts the expression of broad domain-associated genes in preleukemic cells. Finally, an H3K4me3 demethylase inhibitor differentially targets T-ALL cell lines depending on the extent and number of broad domains. Our results show that the regulation of broad H3K4me3 domains is associated with leukemogenesis, and suggest that the presence of these structures might be used for epigenetic prioritization of cancer-relevant genes, including long noncoding RNAs.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Epigénesis Genética , Histonas/metabolismo , Humanos , Oncogenes , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética
3.
Ann Neurol ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39056308

RESUMEN

OBJECTIVE: Susac syndrome (SuS), multiple sclerosis (MS), and primary angiitis of the central nervous system (PACNS) present diagnostic challenges due to overlapping clinical features. We aimed to enhance diagnostic precision by developing the SPAMS (SuS, PACNS, MS) score, a practical radiological tool. METHODS: This multicenter study included 99 patients (43 SuS, 37 MS, 19 PACNS) from South American countries. Relevant MRI features were identified through an elastic-net model determined key variables. RESULTS: The SPAMS score assigned 2 points for snowball lesions, 1 point for spokes-like lesions, or if there are more than 4 lesions in the corpus callosum, corpus callosum involvement, or cerebellar involvement. It subtracted 1 point if gadolinium-enhancing lesions or 4 points if Dawson's fingers are present. Bootstrapping validated the optimal cutoff at 2 points, exhibiting a diagnostic performance of area under the curve = 0.931, sensitivity = 88%, specificity = 89%, positive predictive value = 88%, negative predictive value = 89%, and accuracy = 88%. INTERPRETATION: When specific MRI findings coexisted, the SPAMS score differentiated SuS from MS and PACNS. Access to MRI and standard protocol sequences makes it a valuable tool for timely diagnosis and treatment, potentially preventing disability progression and severe clinical outcomes. ANN NEUROL 2024.

4.
J Urol ; 211(3): 400-406, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38194487

RESUMEN

PURPOSE: There have been conflicting studies on the association between phosphodiesterase type 5 inhibitor (PDE5i) use and biochemical recurrence (BCR) following radical prostatectomy (RP). Our aim was to determine whether PDE5i drug exposure after RP increases the risk of BCR in patients undergoing RP. MATERIALS AND METHODS: An institutional database of prostate cancer patients treated between January 2009 and December 2020 was reviewed. BCR was defined as 2 PSA measurements greater than 0.1 ng/mL. PDE5i exposure was defined using a 0 to 3 scale, with 0 representing never use, 1 sometimes use, 2 regularly use, and 3 routinely use. The risk of BCR with any PDE5i exposure, the quantity of exposure, and the duration of PDE5i exposure were assessed by multivariable Cox proportional hazards models. RESULTS: The sample size included 4630 patients to be analyzed, with 776 patients having BCR. The median follow-up for patients without BCR was 27 (IQR 12, 49) months. Eighty-nine percent reported taking a PDE5i at any time during the first 12 months after RP, and 60% reported doing so for 6 or more months during the year after RP. There was no evidence of an increase in the risk of BCR associated with any PDE5i use (HR 1.05, 95% CI 0.84, 1.31, P = .7) or duration of PDE5i use in the first year (HR 0.98 per 1 month duration, 95% CI 0.96, 1.00, P = .055). Baseline oncologic risk was lower in patients using PDE5i, but differences between groups were small, suggesting that residual confounding is unlikely to obscure any causal association with BCR. CONCLUSIONS: Prescription of PDE5i to men after RP can be based exclusively on quality of life considerations. Patients receiving PDE5is can be reassured that their use does not increase the risk of BCR.


Asunto(s)
Inhibidores de Fosfodiesterasa 5 , Neoplasias de la Próstata , Humanos , Masculino , Inhibidores de Fosfodiesterasa 5/efectos adversos , Calidad de Vida , Próstata , Prostatectomía/efectos adversos , Neoplasias de la Próstata/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Antígeno Prostático Específico , Estudios Retrospectivos
5.
Chemistry ; 30(30): e202400479, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38545936

RESUMEN

The chemical synthesis of complex oligosaccharides relies on efficient and highly reproducible glycosylation reactions. The outcome of a glycosylation is contingent upon several environmental factors, such as temperature, acidity, the presence of residual moisture, as well as the steric, electronic, and conformational aspects of the reactants. Each glycosylation proceeds rapidly and with a high yield within a rather narrow temperature range. For better control over glycosylations and to ensure fast and reliable reactions, a systematic analysis of 18 glycosyl donors revealed the effect of reagent concentration, water content, protecting groups, and structure of the glycosyl donors on the activation temperature. With these insights, we parametrize the first step of the glycosylation reaction to be executed reliably and efficiently.

6.
J Sex Med ; 21(5): 408-413, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38481019

RESUMEN

BACKGROUND: Testosterone (T) plays a crucial role in various physiological functions in men, and understanding the variations in T levels during the day is essential for diagnosing and treating testosterone deficiency (TD). AIM: We sought to evaluate the reduction in serum total T (TT) levels throughout the day in men with symptoms of testosterone deficiency and to determine the variables having an impact on the extent of this decline. METHODS: The study population consisted of a group of men who within 3 months of each other had all undergone both early morning and afternoon TT level measurements. We did not include patients with a history of a prior orchiectomy, testosterone levels below 100 ng/dL or above 1000 ng/dL, a history of androgen deprivation therapy, or patients on T therapy. Statistical analyses were conducted using descriptive statistics, t-tests, chi-square tests, and correlation calculations. Liquid chromatography-tandem mass spectrometry was used to measure TT, and a change in TT levels greater than 100 ng/dL was considered significant. Using multivariable and univariable analysis, we attempted to define predictors of a decrease in afternoon TT levels. OUTCOMES: The majority of men showed no significant difference in T levels between morning and afternoon. RESULTS: In total, 506 men with a median age of 65 years were analyzed. The most common comorbidities were hypertension and hyperlipidemia. Levels of TT were measured in the morning and afternoon, and no significant differences in mean T levels based on the time of the test were found. Age was not significantly associated with T levels. CLINICAL IMPLICATIONS: There was a weak negative correlation between age and the difference between morning and afternoon T levels, with younger men showing more significant variations in T levels. The most considerable differences in T levels were observed in men younger than 30 years. There were no predictors of the magnitude of the T decrease in the afternoon. STRENGTHS AND LIMITATIONS: Strengths of the study include the number of subjects and the use of liquid chromatography-tandem mass spectrometry for T measurement. Limitations include failure to measure morning and afternoon T levels on the same day, the retrospective nature of the study, and a smaller sample size of patients younger than 30 years. CONCLUSION: In this study we found no strong link between age and daily T fluctuation, but we observed a decrease in the magnitude of variation with aging. The group experiencing the most significant decline in daily T had higher morning and consistently normal afternoon T levels.


Asunto(s)
Ritmo Circadiano , Testosterona , Humanos , Masculino , Testosterona/sangre , Testosterona/deficiencia , Anciano , Ritmo Circadiano/fisiología , Persona de Mediana Edad , Hipogonadismo/sangre , Estudios Retrospectivos , Adulto , Espectrometría de Masas en Tándem
7.
Org Biomol Chem ; 22(7): 1395-1399, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38291974

RESUMEN

Herein we utilise automated glycan assembly to complete solid-phase synthesis of defined heparan sulfate oligosaccharides, employing challenging D-glucuronate disaccharide donors. Using an orthogonally protected D-GlcN-α-D-GlcA donor, milligram-scale synthesis of a heparan sulfate tetrasaccharide is completed in 18% yield over five steps. Furthermore, orthogonal protecting groups enabled regiospecific on-resin 6-O-sulfation. This methodology provides an important benchmark for the rapid assembly of biologically relevant heparan sulfate sequences.


Asunto(s)
Heparitina Sulfato , Oligosacáridos , Disacáridos , Glucuronatos , Ácido Glucurónico
8.
Molecules ; 29(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38893463

RESUMEN

Diverse methodologies exist to determine the chemical composition, proximate analysis, and calorific value of biomass. Researchers select and apply a specific methodology according to the lignocellulosic material they study and the budgetary resources available. In this project, we determined the primary chemical constitution and proximate analysis of Prosopis laevigata (Humb. & Bonpl.) Jonhst wood using a traditional chemical method and a novel procedure based on the deconvolution of the DTG signal produced by TGA. The highest calorific value was verified using a calorimetric pump based on mathematical models. We also conducted elemental analysis and a microanalysis of ash, and applied Fourier transform infrared spectroscopic analysis (FT-IR). The means of the results obtained by the chemical method and TGA-DTG, respectively, were: hemicelluloses 7.36%-(8.72%), cellulose 48.28%-(46.08%), lignin 30.57%-(32.44%), extractables 13.53%-(12.72%), moisture 2.03%-(4.96%), ash 1.77%-(1.90%), volatile matter 75.16%-(74.14%), and fixed carbon 23.05%-(18.93%). The procedure with the calorimetric pump generated a calorific value above 20.16 MJ/kg. The range generated by the various models was 18.23-21.07 MJ/kg. The results of the elemental analysis were: carbon 46.4%, hydrogen 6.79%, oxygen 46.43%, nitrogen 0.3%, and sulfur 0.5%. The microanalysis of ash identified 18 elements. The most abundant ones were potassium ˃ calcium ˃ sodium. Based on the infrared spectrum (FT-IR) of Prosopis laevigata wood, we detected the following functional groups: OH, C-H, C=O, CH2, CH3, C-O-C, C-OH, and C4-OH. Our conclusion is that the TGA-DTG method made it possible to obtain results in less time with no need for the numerous reagents that chemical procedures require. The calorific value of P. laevigata wood is higher than the standards. Finally, according to our results, proximate analysis provides the best model for calculating calorific value.


Asunto(s)
Lignina , Prosopis , Termogravimetría , Madera , Madera/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Prosopis/química , Lignina/química , Lignina/análisis , Biomasa , Celulosa/química , Celulosa/análisis , Polisacáridos
9.
Cancer Immunol Immunother ; 72(11): 3825-3838, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37736849

RESUMEN

Breast cancer is the leading malignancy in women worldwide, both in terms of incidence and mortality. Triple-negative breast cancer (TNBC) is the type with the worst clinical outcomes and with fewer therapeutic options than other types of breast cancer. GK-1 is a peptide that in the experimental model of the metastatic 4T1 breast cancer has demonstrated anti-tumor and anti-metastatic properties. Herein, GK-1 (5 mg/kg, i.v.) weekly administrated not only decreases tumor growth and the number of lung macro-metastases but also lung and lymph nodes micro-metastases. Histological analysis reveals that GK-1 reduced 57% of the intra-tumor vascular areas, diminished the leukemoid reaction's progression, and the spleens' weight and length. A significant reduction in VEGF-C, SDF-1, angiopoietin-2, and endothelin-1 angiogenic factors was induced. Moreover, GK-1 prevents T cell exhaustion in the tumor-infiltrating lymphocytes (TILs) decreasing PD-1 expression. It also increased IFN-γ and granzyme-B expression and the cytotoxic activity of CD8+ TILs cells against tumor cells. All these features were found to be associated with a better antitumor response and prognosis. Altogether, these results reinforce the potential of GK-1 to improve the clinical outcome of triple-negative breast cancer immunotherapy. Translation research is ongoing towards its evaluation in humans.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Animales , Ratones , Neoplasias de la Mama Triple Negativas/patología , Agotamiento de Células T , Linfocitos Infiltrantes de Tumor/metabolismo , Pronóstico , Antineoplásicos/uso terapéutico , Linfocitos T CD8-positivos/metabolismo
10.
Chembiochem ; 24(4): e202200607, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36382494

RESUMEN

The synthesis of defined oligosaccharides is a complex task. Several enabling technologies have been introduced in the last two decades to facilitate synthetic access to these valuable biomolecules. In this concept, we describe the technological solutions that have advanced glycochemistry using automated glycan assembly, flow chemistry and data science as examples. We highlight how the synergies between these different technologies can further advance the field, with progress toward the realization of a self-driving lab for glycan synthesis.


Asunto(s)
Ciencia de los Datos , Polisacáridos , Glicosilación , Secuencia de Carbohidratos , Polisacáridos/química , Oligosacáridos/química
11.
Mol Psychiatry ; 27(3): 1562-1572, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35027679

RESUMEN

Clinical guidelines currently recommend practitioners titrate stimulant medications, i.e., methylphenidate (MPH) and amphetamines (AMP), to the dose that maximizes symptom control without eliciting intolerable adverse events (AEs) when treating attention-deficit/hyperactivity disorder (ADHD) in school-aged children/adolescents. However, robust evidence-base regarding the effects of doses and dosing strategies of stimulants on clinical outcomes in the treatment of children/adolescents with ADHD is currently lacking and stimulants are often underdosed in clinical practice. To address this gap and provide rigorous evidence-base in relation to the dose and dosing strategy of stimulants, we conducted the largest systematic review and dose-response meta-analysis examining change in ADHD symptoms (efficacy), and treatment discontinuations due to AEs (tolerability) and any reason (acceptability). We conducted one-stage random-effects dose-response meta-analyses examining MPH and AMP separately, stratifying trials based on fixed-dose and flexible-dose design. Daily doses of stimulants were converted to MPH- and AMP-equivalent doses by adjusting for different pharmacokinetics across formulations. We also conducted pairwise meta-analyses to provide indirect comparisons between flexible-dose versus fixed-dose trials. Our study included 65 RCTs involving 7 877 children/adolescents. Meta-analyses of fixed-dose trials for both MPH and AMP demonstrated increased efficacy and increased likelihood of discontinuation due to AEs with increasing doses of stimulants. The incremental benefits of stimulants in terms of efficacy decreased beyond 30 mg of MPH or 20 mg of AMP in fixed-dosed trials. In contrast, meta-analyses of flexible-dose trials for both MPH and AMP demonstrated increased efficacy and reduced likelihood of discontinuations for any reason with increasing stimulant doses. The incremental benefits of stimulants in terms of efficacy remained constant across the FDA-licensed dose range for MPH and AMP in flexible-dose trials. Our results suggest that flexible titration as needed, i.e., considering the presence of ADHD symptoms, and tolerated, i.e., considering the presence of dose-limiting AEs, to higher doses of stimulants is associated with both improved efficacy and acceptability because practitioners can increase/reduce doses based on control of ADHD symptoms/dose-limiting AEs. Although fixed-dose trials that are required by the FDA are valuable to characterize dose-dependency, they may underestimate the true potential benefit of trialing dose-increases of stimulants in clinical practice by not allowing dose adjustment based on response and tolerability. Additional research is required to investigate potential long-term effects of using high doses of stimulants in clinical practice.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Estimulantes del Sistema Nervioso Central , Metilfenidato , Adolescente , Niño , Humanos , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/uso terapéutico , Metilfenidato/uso terapéutico , Resultado del Tratamiento
12.
Infection ; 51(5): 1273-1284, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36648627

RESUMEN

PURPOSE: Immunocompromised patients have a potentially increased risk for progression to severe COVID-19 and prolonged replication of SARS-CoV-2. This post hoc analysis examined outcomes among immunocompromised participants in the MOVe-OUT trial. METHODS: In phase 3 of MOVe-OUT, non-hospitalized at-risk adults with mild-to-moderate COVID-19 were randomized to receive molnupiravir 800 mg or placebo twice daily for 5 days. Immunocompromised participants were identified based on prior/concomitant medications and/or medical history. All-cause hospitalization/death, adverse events, SARS-CoV-2 titers, infectivity, and RNA sequences were compared between immunocompromised participants who received molnupiravir or placebo and with non-immunocompromised participants. RESULTS: Fifty-five of 1408 participants were considered immunocompromised. Compared to placebo, fewer molnupiravir-treated immunocompromised participants were hospitalized/died through Day 29 (22.6% [7/31] vs. 8.3% [2/24]), with fewer adverse events (45.2% [14/31] vs. 25.0% [6/24]). A larger mean change from baseline in SARS-CoV-2 RNA was observed with molnupiravir compared to placebo in non-immunocompromised participants (least squares mean [LSM] difference Day 5: - 0.31, 95% confidence interval [CI] - 0.47 to - 0.15), while the mean change was comparable between treatment groups in immunocompromised participants (LSM difference Day 5: 0.23, 95% CI - 0.71 to 1.17). Molnupiravir treatment was associated with increased clearance of infectious virus. Increased errors in viral nucleotide sequences in post-baseline samples compared to placebo support molnupiravir's mechanism of action and were not associated with observation of novel treatment-emergent amino acid substitutions in immunocompromised participants. CONCLUSION: Although the study population was small, these data suggest that molnupiravir treatment for mild-to-moderate COVID-19 in non-hospitalized immunocompromised adults is efficacious and safe and quickly reduces infectious SARS-CoV-2. GOV REGISTRATION NUMBER: NCT04575597.


Asunto(s)
COVID-19 , Adulto , Humanos , Tratamiento Farmacológico de COVID-19 , ARN Viral , SARS-CoV-2
13.
J Intensive Care Med ; 38(5): 472-478, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36594202

RESUMEN

BACKGROUND: Members of racial and ethnic minority groups have been disproportionately impacted by coronavirus-2019 (COVID-19). The objective of the study is to describe associations between race and ethnicity on clinical outcomes such as need for mechanical ventilation and mortality. METHODS: Retrospective cohort study of patients with severe COVID-19 infection admitted within a large, not-for-profit healthcare system in the mid-Atlantic region between March and July, 2020. Patient demographic data and clinical outcomes were abstracted from the electronic health record. Logistic regressions were performed to estimate associations between race and ethnicity and the clinical outcomes. RESULTS: The study population (N = 2931) was stratified into 1 of 3 subgroups: non-Hispanic White (n = 466), non-Hispanic Black (n = 1611), and Hispanic (n = 654). The average age of White, Black, and Hispanic patients was 69 ± 17.06, 64 ± 15.9, and 50 ± 15.53 years old, respectively (P < .001). Compared to White patients, Black and Hispanic patients were at increased odds of needing mechanical ventilation due to COVID-19 pneumonia (odds ratio [OR] Black = 1.35, 95% confidence interval [CI] = 1.04 to 1.75, P < .05; OR Hispanic = 1.43, 95% CI = 1.06 to 1.93, P < .05). When compared to White patients, Hispanic patients were at decreased odds of death (OR = 0.45, 95% CI = 0.32 to 0.63, P < .001). However, when adjusting for age, there were no statistically significant differences in the odds of death between these groups (adjusted OR [aOR] Black = 1.05, 95% CI = 0.80 to 1.38, P = .71; aOR Hispanic = 1.10, 95% CI = 0.76 to 1.60, P = .62). CONCLUSION: Our analysis demonstrated that Hispanic patients were more likely require mechanical ventilation but had lower mortality when compared to White patients, with lower average age likely mediating this association. These findings emphasize the importance of outreach efforts to communities of color to increase prevention measures and vaccination uptake to reduce infection with COVID-19.


Asunto(s)
COVID-19 , Etnicidad , Humanos , Negro o Afroamericano , COVID-19/terapia , Grupos Minoritarios , Estudios Retrospectivos , Población Blanca , Hispánicos o Latinos
14.
J Pediatr Hematol Oncol ; 45(3): e345-e349, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36731067

RESUMEN

Few reports on clinical factors, treatment, and survival in children and adolescents with Central nervous system tumors in low-income and middle-income countries in Latin America exist. We retrospectively reviewed such data in all cases of patients younger than 18 years with brain tumors diagnosed in a single tertiary care center in Peru from 2007 through 2017. Variables were analyzed for association with overall survival and event-free survival by using the Kaplan-Meier method and the Cox hazards ratio regression. Seventy-five patients' data were analyzed (40 boys, 35 girls; mean age=7.7 y). The main clinical symptoms were headache, vomiting, difficulty walking, and visual disturbances. The most frequent clinical signs were hydrocephalus, cerebellar signs, visual abnormalities, and focal motor signs. The median time to diagnosis was 12 weeks. Tumor resection was performed in 68 patients, and 37 patients received postoperative radiotherapy. The most frequent histologic subtypes were low-grade gliomas and medulloblastomas. Overall survival rates at 1 and 5 years of disease were 78% (CI 95%, 0.67 to 0.86) and 74% (CI 95%, 0.62 to 0.82), respectively, and the 5-year event-free survival rate was 62% (CI 95%, 0.47 to 0.73). Although diagnosis occurred late in our cohort, the survival rate was higher than that in other Latin American countries.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Neoplasias Cerebelosas , Meduloblastoma , Niño , Masculino , Adolescente , Femenino , Humanos , Estudios Retrospectivos , Perú/epidemiología , Meduloblastoma/terapia , Neoplasias del Sistema Nervioso Central/epidemiología , Neoplasias del Sistema Nervioso Central/terapia , Neoplasias Cerebelosas/terapia
15.
J Chem Phys ; 159(23)2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38117018

RESUMEN

We investigate two limits in open-shell diradical systems: O3, in which the interesting orbitals are in close proximity to one another, and (C21H13)2, where there is a significant spatial separation between the two orbitals. In accord with earlier calculations, we find that standard density-functional approximations do not predict the open-shell character for the former case but uniformly predict the open-shell character for the latter case. We trace the qualitatively incorrect behavior in O3 predicted by these standard density functional approximations to self-interaction error and use the Fermi-Löwdin-orbital-self-interaction-corrected formalism to determine accurate triplet, closed-shell singlet, and open-shell broken-spin-symmetry electronic configurations. Analysis of the resulting many-electron overlap matrices allows us to unambiguously show that the broken-spin-symmetry configurations do not participate in the representation of the Ms = 0 triplet states and allows us to reliably extract the singlet-triplet splitting in O3 by analyzing the energy as a function of Fermi-orbital-descriptor permutations. The results of these analyses predict the percentage of open-shell character in O3, which agrees well with conventional wavefunction-based methods. While these techniques are expected to be required in cases near the Coulson-Fischer point, we find that they will be less necessary in diradical systems with well-separated electrons, such as (C21H13)2. Results based on energies from self-interaction-corrected generalized gradient, local density, and Hartree-Fock approximations and experimental results are in generally good agreement for O3. These results help form the basis for deriving extended Heisenberg-like Hamiltonians that are needed for descriptions of molecular magnets when there are competing low-energy electronic configurations.

16.
Am J Respir Crit Care Med ; 206(9): 1081-1095, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35776514

RESUMEN

Rationale: MUC5AC (mucin 5AC, oligomeric gel-forming) and MUC5B (mucin 5B, oligomeric gel-forming) are the predominant secreted polymeric mucins in mammalian airways. They contribute differently to the pathogenesis of various muco-obstructive and interstitial lung diseases, and their genes are separately regulated, but whether they are packaged together or in separate secretory granules is not known. Objectives: To determine the packaging of MUC5AC and MUC5B within individual secretory granules in mouse and human airways under varying conditions of inflammation and along the proximal-distal axis. Methods: Lung tissue was obtained from mice stimulated to upregulate mucin production by the cytokines IL-1ß and IL-13 or by porcine pancreatic elastase. Human lung tissue was obtained from donated normal lungs, biopsy samples of transplanted lungs, and explanted lungs from subjects with chronic obstructive pulmonary disease. MUC5AC and MUC5B were labeled with antibodies from different animal species or, in mice only, by transgenic chimeric mucin-fluorescent proteins and imaged using widefield deconvolution or Airyscan fluorescence microscopy. Measurements and Main Results: In both mouse and human airways, most secretory granules contained both mucins interdigitating within the granules. Smaller numbers of granules contained MUC5B alone, and even fewer contained MUC5AC alone. Conclusions: MUC5AC and MUC5B are variably stored both in the same and in separate secretory granules of both mice and humans. The high fraction of granules containing both mucins under a variety of conditions makes it unlikely that their secretion can be differentially controlled as a therapeutic strategy. This work also advances knowledge of the packaging of mucins within secretory granules to understand mechanisms of epithelial stress in the pathogenesis of chronic lung diseases.


Asunto(s)
Mucina 5B , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Ratones , Animales , Porcinos , Mucina 5AC , Pulmón/metabolismo , Vesículas Secretoras/metabolismo , Mamíferos/metabolismo
17.
Int J Mol Sci ; 24(18)2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37762475

RESUMEN

Stressed organisms identify intracellular molecules released from damaged cells due to trauma or pathogen infection as components of the innate immune response. These molecules called DAMPs (Damage-Associated Molecular Patterns) are extracellular ATP, sugars, and extracellular DNA, among others. Animals and plants can recognize their own DNA applied externally (self-exDNA) as a DAMP with a high degree of specificity. However, little is known about the microalgae responses to damage when exposed to DAMPs and specifically to self-exDNAs. Here we compared the response of the oilseed microalgae Neochloris oleoabundans to self-exDNA, with the stress responses elicited by nonself-exDNA, methyl jasmonate (MeJA) and sodium bicarbonate (NaHCO3). We analyzed the peroxidase enzyme activity related to the production of reactive oxygen species (ROS), as well as the production of polyphenols, lipids, triacylglycerols, and phytohormones. After 5 min of addition, self-exDNA induced peroxidase enzyme activity higher than the other elicitors. Polyphenols and lipids were increased by self-exDNA at 48 and 24 h, respectively. Triacylglycerols were increased with all elicitors from addition and up to 48 h, except with nonself-exDNA. Regarding phytohormones, self-exDNA and MeJA increased gibberellic acid, isopentenyladenine, and benzylaminopurine at 24 h. Results show that Neochloris oleoabundans have self-exDNA specific responses.


Asunto(s)
Chlorophyceae , Microalgas , Animales , Reguladores del Crecimiento de las Plantas , Peroxidasa , Alarminas , Colorantes , ADN , Oxilipinas , Peroxidasas
18.
J Environ Manage ; 345: 118901, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37688958

RESUMEN

Increasing irrigation demand has heavily relied on groundwater use, especially in places with highly variable water supplies that are vulnerable to drought. Groundwater management in agriculture is becoming increasingly challenging given the growing effects from overdraft and groundwater depletion worldwide. However, multiple challenges emerge when seeking to develop sustainable groundwater management in irrigated systems, such as trade-offs between the economic revenues from food production and groundwater resources, as well as the broad array of uncertainties in food-water systems. In this study we explore the applicability of Evolutionary Multi-Objective Direct Policy Search (EMODPS) to identify adaptive irrigation policies that water agencies and farmers can implement including operational decisions related to land use and groundwater use controls as well as groundwater pumping fees. The EMODPS framework yields state-aware, adaptive policies that respond dynamically as system state conditions change, for example with variable surface water (e.g., shifting management strategies across wet versus dry years). For this study, we focus on the Semitropic Water Storage district located in the San Joaquin Valley, California to provide broader insights relevant to ongoing efforts to improve groundwater sustainability in the state. Our findings demonstrate that adaptive irrigation policies can achieve sufficiently flexible groundwater management to acceptably balance revenue and sustainability goals across a wide range of uncertain future scenarios. Among the evaluated policy decisions, pumping restrictions and reductions in inflexible irrigation demands from tree crops are actions that can support dry-year pumping while maximizing groundwater storage recovery during wet years. Policies suggest that an adaptive pumping fee is the most flexible decision to control groundwater pumping and land use.


Asunto(s)
Conservación de los Recursos Naturales , Agua Subterránea , Abastecimiento de Agua , Agricultura , Incertidumbre
19.
Rev Esp Enferm Dig ; 115(6): 346, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37232169

RESUMEN

A 68-year-old woman with stage IV pancreatic adenocarcinoma (liver and lymph node metastases) on first-line treatment with gemcitabine. As a non-oncological comorbidity, the patient was anticoagulated with enoxaparin 8000 IU/24 hours because she had a mitral valve prosthesis. The patient made a medical consultation for presenting vomits which looked like coffee grounds and melaena. In the complete blood count, a hemoglobin of 7.5 g/dL was detected. Transfusion support, pantoprazole infusion (80 mg in 500 cc of 0.9% SSF every 12 hours) and parenteral nutrition were prescribed. Tranexamic was not prescribed due to the patient's cardiological history.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Femenino , Humanos , Anciano , Neoplasias Pancreáticas/complicaciones , Adenocarcinoma/complicaciones , Duodeno , Hemorragia , Neoplasias Pancreáticas
20.
J Infect Dis ; 226(5): 778-787, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-35294530

RESUMEN

BACKGROUND: The impact of genetic variants in the expression of tumor necrosis factor-α (TNF-α) and its receptors in coronavirus disease 2019 (COVID-19) severity has not been previously explored. We evaluated the association of TNF (rs1800629 and rs361525), TNFRSF1A (rs767455 and rs1800693), and TNFRSF1B (rs1061622 and rs3397) variants with COVID-19 severity, assessed as invasive mechanical ventilation (IMV) requirement, and the plasma levels of soluble TNF-α, TNFR1, and TNFR2 in patients with severe COVID-19. METHODS: The genetic study included 1353 patients. Taqman assays were used to assess the genetic variants. ELISA was used to determine soluble TNF-α, TNFR1, and TNFR2 in plasma samples from 334 patients. RESULTS: Patients carrying TT (TNFRSF1B rs3397) exhibited lower PaO2/FiO2 levels than those with CT + CC genotypes. Differences in plasma levels of TNFR1 and TNFR2 were observed according to the genotype of TNFRSF1B rs1061622, TNF rs1800629, and rs361525. According to the studied genetic variants, there were no differences in the soluble TNF-α levels. Higher soluble TNFR1 and TNFR2 levels were detected in patients with COVID-19 requiring IMV. CONCLUSIONS: Genetic variants in TNF and TNFRSFB1 influence the plasma levels of soluble TNFR1 and TNFR2, implicated in COVID-19 severity.


Asunto(s)
COVID-19 , Receptores Tipo II del Factor de Necrosis Tumoral , COVID-19/genética , Genotipo , Humanos , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Receptores Tipo II del Factor de Necrosis Tumoral/genética , Factor de Necrosis Tumoral alfa/genética
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