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1.
Plant J ; 111(4): 1052-1068, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35710867

RESUMEN

Plants respond to low temperatures by altering the mRNA abundance of thousands of genes contributing to numerous physiological and metabolic processes that allow them to adapt. At the post-transcriptional level, these cold stress-responsive transcripts undergo alternative splicing, microRNA-mediated regulation and alternative polyadenylation, amongst others. Recently, m6 A, m5 C and other mRNA modifications that can affect the regulation and stability of RNA were discovered, thus revealing another layer of post-transcriptional regulation that plays an important role in modulating gene expression. The importance of m6 A in plant growth and development has been appreciated, although its significance under stress conditions is still underexplored. To assess the role of m6 A modifications during cold stress responses, methylated RNA immunoprecipitation sequencing was performed in Arabidopsis seedlings esposed to low temperature stress (4°C) for 24 h. This transcriptome-wide m6 A analysis revealed large-scale shifts in this modification in response to low temperature stress. Because m6 A is known to affect transcript stability/degradation and translation, we investigated these possibilities. Interestingly, we found that cold-enriched m6 A-containing transcripts demonstrated the largest increases in transcript abundance coupled with increased ribosome occupancy under cold stress. The significance of the m6 A epitranscriptome on plant cold tolerance was further assessed using the mta mutant in which the major m6 A methyltransferase gene was mutated. Compared to the wild-type, along with the differences in CBFs and COR gene expression levels, the mta mutant exhibited hypersensitivity to cold treatment as determined by primary root growth, biomass, and reactive oxygen species accumulation. Furthermore, and most importantly, both non-acclimated and cold-acclimated mta mutant demonstrated hypersensitivity to freezing tolerance. Taken together, these findings suggest a critical role for the epitranscriptome in cold tolerance of Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Frío , Congelación , Regulación de la Expresión Génica de las Plantas/genética , ARN Mensajero/genética
2.
Front Neuroendocrinol ; 66: 100995, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35421511

RESUMEN

INTRODUCTION: Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS) is a complex multisystem disease characterised by severe and disabling new-onset symptoms of post-exertional malaise (PEM), fatigue, brain fog, and sleep dysfunction that lasts for at least six months. Accumulating evidence suggests that sex and endocrine events have a significant influence on symptom onset and moderation of ME/CFS, with female sex being one of the most consistent and credible predictive risk factors associated with diagnosis. Such sex differences suggest sex chromosomes and sex steroids may play a part in the development of the condition or moderation of symptoms, although this has yet to be explored in detail. METHODS/AIMS: This narrative review outlines sex differences in ME/CFS in terms of vulnerability factors and clinical phenotype and explores the known sex differences in neuroendocrine systems affected in ME/CFS and how this may relate to disease risk, onset, pathophysiology, and potential treatment avenues. CONCLUSIONS: There is clear evidence of a sex dimorphism with regards to prevalence (3:1 female preponderance), clinical phenotypes, and aetiological triggers prior to symptom onset of ME/CFS. Endocrinological events, particularly those throughout the female lifespan, are associated with ME/CFS and include reproductive menstrual cycle fluctuations, pregnancy, post-partum and perimenopause. Further, there is evidence for gonadal sex, adrenal stress and renal neuroendocrine systems as implicated in ME/CFS, including changes in estrogen, progesterone compounds, aldosterone, and cortisol levels, of which there are established sex differences. The broad effects of steroid hormones on the physiological systems may also speak to the diversity of ME/CFS symptomatology observed in patients. Further attention must be paid to sex, age, and steroid biology in ME/CFS.


Asunto(s)
Síndrome de Fatiga Crónica , Síndrome de Fatiga Crónica/diagnóstico , Síndrome de Fatiga Crónica/epidemiología , Síndrome de Fatiga Crónica/etiología , Femenino , Hormonas , Humanos , Masculino , Sistemas Neurosecretores , Caracteres Sexuales
3.
Bioorg Med Chem ; 78: 117131, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36571976

RESUMEN

To follow up on our previous report on bivalent compounds exhibiting potent co-operative binding at dopamine D2 receptors, we modified the structure of the linker in our earlier bivalent molecules (S)-6-((9-(((R)-5-hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)(propyl)amino)nonyl)-(propyl)amino)-5,6,7,8-tetrahydronaphthalen-1-ol (Ia) and (S)-6-((10-(((R)-5-hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)(propyl)amino)decyl)(propyl)amino)-5,6,7,8-tetrahydronaphthalen-1-ol (Ib) (Fig. 1) connecting the two pharmaophoric moieties to observe any tolerance in maintaining similar affinities and potencies. Specifically, we introduced aromatic and piperazine moieties in the linker to explore their effect. Overall, similar activities at D2 receptors as observed in our earlier study was maintained in the new molecules e.g. (6S,6'S)-6,6'-((1,4-phenylenebis(ethane-2,1-diyl))bis(propylazanediyl))bis(5,6,7,8-tetrahydronaphthalen-1-ol) (D-382) (Ki, D2 = 3.88 nM). The aromatic moiety in D-382 was next functionalized by introducing hydroxyl groups to mimic polyhydroxy natural products which are known to interact with amyloidogenic proteins. Such a transformation resulted in development of compounds like 2,5-bis(2-(((S)-5-hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)(propyl)amino)ethyl)benzene-1,4-diol (D-666) (Ki, D2 = 7.62 nM) which retained similar affinity and potency at D2 receptors. Such dihydroxyl compounds turned out to be potent inhibitors against aggregation and toxicity of recombinant alpha synuclein protein. The work reported here is in line with our overall goal to develop multifunctional dopamine agonist for symptomatic and disease modifying treatment of Parkinson's disease.


Asunto(s)
Agonistas de Dopamina , Receptores de Dopamina D2 , alfa-Sinucleína , Agonistas de Dopamina/farmacología , Agonistas de Dopamina/química , Piperazinas/farmacología , Receptores de Dopamina D1 , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/agonistas
4.
Front Neuroendocrinol ; 63: 100946, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34481858

RESUMEN

Stress homeostatic mediators are the most consistently anomalous biomarkers observed in suicide and may therefore point to a common 'core biology' of stress susceptibility, and suicidal behaviour. Previously reported meta-analyses have demonstrated aberrant levels of stress cortisol and inflammatory cytokines in suicide patients compared to controls, and significant associations between the stress regulator FK506-binding protein 51 (FKBP5) gene and suicidal behaviour. Although these independent studies were investigated as separate entities in suicide, stress mediators interact in a dynamic system, collectively giving rise to system changes physiologically, and ultimately psychologically and behaviourally. It is therefore important to study the dynamic network these stress mediators. Network meta-analysis allows for the simultaneous comparison of more than two biological mediators, and for comparisons to be made between mediators that have not been directly compared before, using previously reported, pooled meta data. Such network approaches may help study the complex biological phenomena of suicide and may provide better prediction of biological risk of suicidal states. METHODS: This study aimed to establish the comparative relationships between key stress mediators in suicidal patients compared to non-suicidal controls using a random-effects network meta-analysis approach.. The key stress mediators included cortisol, six inflammatory markers (interleukin-6 (IL-6), interleukin-4 (IL-4), interleukin-2 (IL-2), tumour necrosis factor-a (TNF-α), interferon (IFN-y) and transforming growth factor ß (TGF-ß), and the FKBP5 single nucleotide polymorphism (SNP) allele. Data was derived from three previously published meta-analysis. The study population comprised of 1348 suicidal patients, defined as suicide attempters, completers, or patients with severe suicidal ideation, and 1750 non-suicidal controls, defined as healthy controls and psychiatric patients without suicidal ideation or previous attempts. RESULTS: Pair-wise indirect effects of stress mediators in suicide compared to controls demonstrated that relative to the effect of the FKBP5 risk SNP allele on suicide risk, the magnitude of differences (suicide vs control) for the levels of IL-2 (SMD -0.72; 95% CI, -0.135 to -0.09 and IL-4 (SMD -0.71; 95% CI, -1.34 to -0.08) were significantly smaller (with 95% confidence intervals not crossing the null). The comparative relationships between stress mediators in suicidal behaviour demonstrates that the dynamic stress network relationship is dysregulated in suicide patients when compared to controls. CONCLUSIONS: This model suggests that a genetic stress susceptibility with downstream abnormal cortisol stress axis functioning, together with anomalous interactions between the inflammatory system, may be one of the neurobiological correlates of suicide behaviour. This biological state may leave the individual physiologically susceptible and unable to cope with environmental stressors, which is consistent with the stress-diathesis hypothesis of suicide behaviour.


Asunto(s)
Ideación Suicida , Suicidio , Biomarcadores , Citocinas , Humanos , Metaanálisis en Red
5.
J Public Health Manag Pract ; 28(4): 425-429, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35121712

RESUMEN

The Cherokee Nation Cancer Registry (CNCR) is the only tribally operated Surveillance, Epidemiology, and End Results program registry. As registries, including the CNCR, lack detailed data characterizing health behavior or comorbidity, we aimed to enrich the CNCR by linking it with Cherokee Nation's electronic medical record (EMR). We describe the process of a tribal-academic partnership and linking records between the CNCR and the EMR for American Indian people diagnosed with cancer from 2015 to 2020. Prior to data linkage, our team worked with the Cherokee Nation Governance Board and Institutional Review Board to ensure tribal data sovereignty was maintained. While not all persons in the CNCR receive health care at Cherokee Nation, 63% linked with an EMR. We observed differences (P < .001) between cancer site, year at diagnosis, age at diagnosis, and gender by EMR linkage status. Once we further validate linkages and assess data completeness, we will evaluate relationships between behavioral risk factors, comorbidities, and cancer outcomes.


Asunto(s)
Indígenas Norteamericanos , Neoplasias , Atención a la Salud/métodos , Registros Electrónicos de Salud , Conductas Relacionadas con la Salud , Humanos , Neoplasias/epidemiología , Sistema de Registros
6.
Surg Endosc ; 33(9): 3001-3007, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30386988

RESUMEN

INTRODUCTION: Bariatric surgery has been shown to be a safe and durable intervention for patients struggling with obesity and metabolic syndrome, including hypertension. Buchwald et al. reported hypertension resolution rates in 67.1% and improvement in 78.5% following aggregate bariatric surgery. The laparoscopic sleeve gastrectomy (LSG) is becoming increasingly utilized as a primary bariatric surgery, but lacks long-term outcome data. There are a growing number of studies reporting outcome data beyond 5 years. OBJECTIVE: This study aims to systematically evaluate the efficacy of laparoscopic sleeve gastrectomy on hypertension amongst obese patients. MATERIALS AND METHODS: A comprehensive literature search was conducted through Medline, Embase, Scopus, Web of Science, Dare, Cochrane library, and HTA database. The search terms used were broad: sleeve gastrectomy AND hypertension OR blood pressure. Adult patients undergoing LSG with follow-up hypertension outcome results of at least 5 years were included. Revisional surgeries were excluded. Two independent reviewers were used. RESULTS: Fourteen studies were included in this systematic review, which included 3550 subjects in total. Mean age was 41.1 ± 10.7 years. Mean pre-operative BMI and weight were 47.7 ± 8.83 kg/m2 and 272.8 ± 48.4 lb, respectively. Pre-operative prevalence of hypertension was 36.5% (range 6.7-91%) which dropped to 14.79% (range 0-33.3%) at approximately 5-year follow-up. Hypertension resolved in 62.17% (range 0-100%) of patients and improved in 35.7% (range 13.3-76.9%) at a mean of 5.35 years of follow-up. CONCLUSION: From this systematic review, LSG is an effective intervention for bariatric patients with hypertension. In addition to the observed reduction in the incidence of hypertension, it is likely that LSG may lead to additional health system benefits such as cost savings due to reductions in antihypertensive medications. Further prospective studies should include estimates of cost savings associated with reductions in chronic antihypertensive medication usage.


Asunto(s)
Presión Sanguínea/fisiología , Gastrectomía/métodos , Hipertensión/complicaciones , Laparoscopía/métodos , Obesidad Mórbida/cirugía , Estudios de Seguimiento , Humanos , Hipertensión/fisiopatología , Obesidad Mórbida/complicaciones , Estudios Prospectivos , Factores de Tiempo
7.
Can J Surg ; 61(4): 237-243, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30067181

RESUMEN

BACKGROUND: Emergency general surgery (EGS) services are gaining popularity in Canada as systems-based approaches to surgical emergencies. Despite the high volume, acuity and complexity of the patient populations served by EGS services, little has been reported about the services' structure, processes, case mix or outcomes. This study begins a national surveillance effort to define and advance surgical quality in an important and diverse surgical population. METHODS: A national cross-sectional study of EGS services was conducted during a 24-hour period in January 2017 at 14 hospitals across 7 Canadian provinces recruited through the Canadian Association of General Surgeons Acute Care Committee. Patients admitted to the EGS service, new consultations and off-service patients being followed by the EGS service during the study period were included. Patient demographic information and data on operations, procedures and complications were collected. RESULTS: Twelve sites reported resident coverage. Most services did not include trauma. Ten sites had protected operating room time. Overall, 393 patient encounters occurred during the study period (195/386 [50.5%] operative and 191/386 [49.5%] nonoperative), with a mean of 3.8 operations per service. The patient population was complex, with 136 patients (34.6%) having more than 3 comorbidities. There was a wide case mix, including gallbladder disease (69 cases [17.8%]) and appendiceal disease (31 [8.0%]) as well as complex emergencies, such as obstruction (56 [14.5%]) and perforation (23 [5.9%]). CONCLUSION: The characteristics and case mix of these Canadian EGS services are heterogeneous, but all services are busy and provide comprehensive operative and nonoperative care to acutely ill patients with high levels of comorbidity.


CONTEXTE: Les services de chirurgie générale d'urgence (CGU) gagnent en popularité au Canada en tant qu'approches systémiques aux urgences chirurgicales. Malgré le volume élevé, le caractère urgent et la complexité des populations de patients desservies en CGU, peu de rapports ont porté sur la structure, les processus, les clientèles ou les résultats de ces services. La présente étude instaure une démarche de surveillance nationale qui servira à définir et à améliorer la qualité des chirurgies destinées à cette population importante et hétérogène. MÉTHODES: Une étude transversale nationale sur les services de CGU a été réalisée sur une période de 24 heures en janvier 2017 dans 14 hôpitaux de 7 provinces canadiennes recrutés par l'entremise du comité pour les soins aigus de l'Association canadienne des chirurgiens généraux. On y a inclus les patients admis dans les services de CGU, les nouvelles consultations et les patients de l'extérieur suivis par les services de CGU pendant la période de l'étude. On a recueilli les caractéristiques démographiques des patients et les données sur les interventions, les procédures et les complications. RÉSULTATS: Douze sites ont fait état de la couverture assurée par les résidents. La plupart des services ont exclu la traumatologie. Dix sites disposaient de temps protégé au bloc opératoire. En tout, 393 rencontres avec des patients ont eu lieu pendant la période de l'étude (195/386 [50,4 %] chirurgicales, 191/386 [49,5 %] non chirurgicales), avec une moyenne de 3,8 chirurgies par service. La population regroupait des cas complexes : 136 patients (34,6 %) présentaient plus de 3 comorbidités. La clientèle était diversifiée et comprenait des cas de maladie de la vésicule biliaire (69 cas [17,8 %]) et de l'appendice (31 [8,0 %]), de même que des situations d'urgence délicates, telle qu'obstruction (56 [14,5 %]) et perforation (23 [5,9 %]). CONCLUSION: Leurs caractéristiques et leurs clientèles sont hétérogènes, mais les services de CGU sont tous achalandés et ils offrent tous des soins chirurgicaux et non chirurgicaux complets à des patients gravement malades porteurs d'importantes comorbidités.


Asunto(s)
Cirugía General/organización & administración , Traumatología/organización & administración , Canadá , Estudios Transversales , Grupos Diagnósticos Relacionados , Humanos , Flujo de Trabajo
8.
Antimicrob Agents Chemother ; 59(9): 5511-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26124156

RESUMEN

There is a pressing need for new antimicrobial therapies to combat globally important drug-resistant human pathogens, including Plasmodium falciparum malarial parasites, Mycobacterium tuberculosis, and Gram-negative bacteria, including Escherichia coli. These organisms all possess the essential methylerythritol phosphate (MEP) pathway of isoprenoid biosynthesis, which is not found in humans. The first dedicated enzyme of the MEP pathway, 1-deoxy-d-xylulose 5-phosphate reductoisomerase (Dxr), is inhibited by the phosphonic acid antibiotic fosmidomycin and its analogs, including the N-acetyl analog FR900098 and the phosphoryl analog fosfoxacin. In order to identify mutations in dxr that confer resistance to these drugs, a library of E. coli dxr mutants was screened at lethal fosmidomycin doses. The most resistant allele (with the S222T mutation) alters the fosmidomycin-binding site of Dxr. The expression of this resistant allele increases bacterial resistance to fosmidomycin and other fosmidomycin analogs by 10-fold. These observations confirm that the primary cellular target of fosmidomycin is Dxr. Furthermore, cell lines expressing Dxr-S222T will be a powerful tool to confirm the mechanisms of action of future fosmidomycin analogs.


Asunto(s)
Isomerasas Aldosa-Cetosa/genética , Antibacterianos/farmacología , Fosfomicina/análogos & derivados , Mycobacterium tuberculosis/enzimología , Profármacos/farmacología , Fosfomicina/farmacología , Pruebas de Sensibilidad Microbiana , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética
9.
Antimicrob Agents Chemother ; 59(10): 6203-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26248369

RESUMEN

Malaria and HIV infection are coendemic in a large portion of the world and remain a major cause of morbidity and mortality. Growing resistance of Plasmodium species to existing therapies has increased the need for new therapeutic approaches. The Plasmodium glucose transporter PfHT is known to be essential for parasite growth and survival. We have previously shown that HIV protease inhibitors (PIs) act as antagonists of mammalian glucose transporters. While the PI lopinavir is known to have antimalarial activity, the mechanism of action is unknown. We report here that lopinavir blocks glucose uptake into isolated malaria parasites at therapeutically relevant drug levels. Malaria parasites depend on a constant supply of glucose as their primary source of energy, and decreasing the available concentration of glucose leads to parasite death. We identified the malarial glucose transporter PfHT as a target for inhibition by lopinavir that leads to parasite death. This discovery provides a mechanistic basis for the antimalarial effect of lopinavir and provides a direct target for novel drug design with utility beyond the HIV-infected population.


Asunto(s)
Glucosa/antagonistas & inhibidores , Inhibidores de la Proteasa del VIH/farmacología , Lopinavir/farmacología , Proteínas de Transporte de Monosacáridos/antagonistas & inhibidores , Plasmodium falciparum/efectos de los fármacos , Proteínas Protozoarias/antagonistas & inhibidores , Antimaláricos/química , Antimaláricos/farmacología , Transporte Biológico , Reposicionamiento de Medicamentos , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Eritrocitos/parasitología , Expresión Génica , Glucosa/metabolismo , Células HEK293 , Inhibidores de la Proteasa del VIH/química , Humanos , Concentración 50 Inhibidora , Lopinavir/química , Proteínas de Transporte de Monosacáridos/genética , Proteínas de Transporte de Monosacáridos/metabolismo , Plasmodium falciparum/genética , Plasmodium falciparum/crecimiento & desarrollo , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad
10.
Environ Sci Technol ; 49(3): 1286-93, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25535652

RESUMEN

This work presents the findings of a long-term plutonium (Pu) study at Savannah River Site (SRS) conducted between 2003 and 2013. Terrestrial environmental samples were obtained at the Savannah River National Laboratory (SRNL) in the A-Area. Plutonium content and isotopic abundances were measured over this time period by α particle and thermal ionization mass spectrometry (3STIMS). We detail the complete process of the sample collection, radiochemical separation, and measurement procedure specifically targeted to trace plutonium in bulk environmental samples. Total plutonium activities were determined to be not significantly above atmospheric global fallout. However, the (238)Pu/(239+240)Pu activity ratios attributed to SRS are substantially different than fallout due to past (238)Pu production on the site. The (240)Pu/(239)Pu atom ratios are reasonably consistent from year to year and are lower than fallout indicating an admixture of weapons-grade material, while the (242)Pu/(239)Pu atom ratios are higher than fallout values, again due to actinide production activities. Overall, the plutonium signatures obtained in this study reflect a distinctive mixture of weapons-grade, heat source, and higher burn-up plutonium with fallout material. This study provides a unique opportunity for developing and demonstrating a blue print for long-term low-level monitoring of trace plutonium in the environment.


Asunto(s)
Sedimentos Geológicos/química , Plutonio/análisis , Monitoreo de Radiación/métodos , Ríos , Contaminantes Radiactivos del Suelo/análisis , Estudios Longitudinales , Espectrometría de Masas/métodos , Radioisótopos/análisis , Estados Unidos
11.
Proc Natl Acad Sci U S A ; 109(6): 1874-7, 2012 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-22308442

RESUMEN

The Fukushima-Daiichi nuclear accident brought together compromised irradiated fuel and large amounts of seawater in a high radiation field. Based on newly acquired thermochemical data for a series of uranyl peroxide compounds containing charge-balancing alkali cations, here we show that nanoscale cage clusters containing as many as 60 uranyl ions, bonded through peroxide and hydroxide bridges, are likely to form in solution or as precipitates under such conditions. These species will enhance the corrosion of the damaged fuel and, being thermodynamically stable and kinetically persistent in the absence of peroxide, they can potentially transport uranium over long distances.


Asunto(s)
Energía Nuclear , Agua de Mar/química , Compuestos de Uranio/análisis , Corrosión , Iones , Modelos Moleculares , Termodinámica
12.
Proc Natl Acad Sci U S A ; 108(36): 14775-9, 2011 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-21852572

RESUMEN

The ε-Al(13) Keggin aluminum hydroxide clusters are essential models in establishing molecular pathways for geochemical reactions. Enthalpies of formation are reported for two salts of aluminum centered ε-Keggin clusters, Al(13) selenate, (Na(AlO(4))Al(12)(OH)(24)(SeO(4))(4)•12H(2)O) and Al(13) sulfate, (NaAlO(4)Al(12)(OH)(24)(SO(4))(4)•12H(2)O). The measured enthalpies of solution, ΔH(sol), at 28 °C in 5 N HCl for the ε-Al(13) selenate and sulfate are -924.57 (± 3.83) and -944.30 ( ± 5.66) kJ·mol(-1), respectively. The enthalpies of formation from the elements, ΔH(f,el), for Al(13) selenate and sulfate are -19,656.35 ( ± 67.30) kJ·mol(-1), and -20,892.39 ( ± 70.01) kJ·mol(-1), respectively. In addition, ΔH(f,el) for sodium selenate decahydrate was calculated using data from high temperature oxide melt solution calorimetry measurements: -4,006.39 ( ± 11.91) kJ·mol(-1). The formation of both ε-Al(13) Keggin cluster compounds is exothermic from oxide-based components but energetically unfavorable with respect to a gibbsite-based assemblage. To understand the relative affinity of the ε-Keggin clusters for selenate and sulfate, the enthalpy associated with two S-Se exchange reactions was calculated. In the solid state, selenium is favored in the Al(13) compound relative to the binary chalcogenate, while in 5 N HCl, sulfur is energetically favored in the cluster compound compared to the aqueous solution. This contribution represents the first thermodynamic study of ε-Al(13) cluster compounds and establishes a method for other such molecules, including the substituted versions that have been created for kinetic studies. Underscoring the importance of ε-Al(13) clusters in natural and anthropogenic systems, these data provide conclusive thermodynamic evidence that the Al(13) Keggin cluster is a crucial intermediate species in the formation pathway from aqueous aluminum monomers to aluminum hydroxide precipitates.

13.
Trends Mol Med ; 30(5): 443-458, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38443223

RESUMEN

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating chronic illness often triggered by an initiating acute event, mainly viral infections. The transition from acute to chronic disease remains unknown, but interest in this phenomenon has escalated since the COVID-19 pandemic and the post-COVID-19 illness, termed 'long COVID' (LC). Both ME/CFS and LC share many clinical similarities. Here, we present recent findings in ME/CFS research focussing on proposed disease pathologies shared with LC. Understanding these disease pathologies and how they influence each other is key to developing effective therapeutics and diagnostic tests. Given that ME/CFS typically has a longer disease duration compared with LC, with symptoms and pathologies evolving over time, ME/CFS may provide insights into the future progression of LC.


Asunto(s)
COVID-19 , Síndrome de Fatiga Crónica , Síndrome Post Agudo de COVID-19 , SARS-CoV-2 , Humanos , COVID-19/complicaciones , COVID-19/virología , Síndrome de Fatiga Crónica/virología
14.
Nat Genet ; 34(1): 35-41, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12679813

RESUMEN

To verify the genome annotation and to create a resource to functionally characterize the proteome, we attempted to Gateway-clone all predicted protein-encoding open reading frames (ORFs), or the 'ORFeome,' of Caenorhabditis elegans. We successfully cloned approximately 12,000 ORFs (ORFeome 1.1), of which roughly 4,000 correspond to genes that are untouched by any cDNA or expressed-sequence tag (EST). More than 50% of predicted genes needed corrections in their intron-exon structures. Notably, approximately 11,000 C. elegans proteins can now be expressed under many conditions and characterized using various high-throughput strategies, including large-scale interactome mapping. We suggest that similar ORFeome projects will be valuable for other organisms, including humans.


Asunto(s)
Caenorhabditis elegans/genética , Genoma , Empalme Alternativo , Animales , Clonación Molecular , ADN Complementario/genética , ADN de Helmintos/genética , Bases de Datos Genéticas , Exones , Etiquetas de Secuencia Expresada , Expresión Génica , Genes de Helminto , Genómica , Proteínas del Helminto/genética , Humanos , Intrones , Sistemas de Lectura Abierta , Proteoma , Proteómica
15.
ACS Chem Neurosci ; 14(5): 885-896, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36749600

RESUMEN

Aggregation of misfolded α-synuclein (α-syn) protein in the periphery and central nervous system (CNS) gives rise to a group of disorders, which are labeled collectively as synucleinopathies. These clinically distinct disorders are known as pure autonomic failure, Parkinson's disease (PD), Parkinson's disease dementia (PDD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). In the case of PD, it has been demonstrated that toxic aggregates of α-syn protein not only cause apoptosis of dopamine neurons but its accumulation in the neocortex and limbic area principally contributes to dementia. In our multifunctional drug discovery research for PD, we converted one of our catechol-containing lead dopamine agonist molecules D-520 into its prodrug D-685. The prodrug exhibited higher in vivo anti-Parkinsonian efficacy in a reserpinized PD animal model than the parent D-520 and exhibited facile brain penetration. In our study with an α-syn transgenic animal model (D line) for PD and dementia with Lewy bodies (DLB), we have shown that 1 month of chronic treatment with the compound D-685 was sufficient to reduce the accumulation of α-syn and phospho-α-syn in the cortex, hippocampus, and striatum areas significantly compared to the control tg mice. Furthermore, D-685 did not exhibit any deleterious effect in the CNS as was evident from the neuron and microglia studies. Future studies will further explore in depth the potential of D-685 to modify disease progression while addressing symptomatic deficits.


Asunto(s)
Demencia , Enfermedad por Cuerpos de Lewy , Enfermedad de Parkinson , Profármacos , Humanos , Ratones , Animales , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Modelos Animales de Enfermedad
16.
Front Immunol ; 14: 1178882, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38259473

RESUMEN

Introduction: Disturbances of energy metabolism contribute to the clinical manifestations of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Previously, we found that B cells from ME/CFS patients have an increased expression of CD24, a modulator of many cellular functions including those of cell stress. The relative ability of B cells from ME/CFS patients and healthy controls (HC) to respond to rapid changes in energy demand was compared. Methods: CD24, the ectonucleotidases CD39 and CD73, the NAD-degrading enzyme CD38, and mitochondrial mass (MM) were measured following cross-linking of the B cell receptor and costimulation with either T-cell-dependent or Toll-like-receptor-9-dependent agonists. The levels of metabolites consumed/produced were measured using 1H-NMR spectroscopy and analyzed in relation to cell growth and immunophenotype. Results: Proliferating B cells from patients with ME/CFS showed a lower mitochondrial mass and a significantly increased usage of essential amino acids compared with those from HC, with a significantly delayed loss of CD24 and an increased expression of CD38 following stimulation. Discussion: The immunophenotype results suggested the triggering of a stress response in ME/CFS B cells associated with the increased usage of additional substrates to maintain necessary ATP levels. Disturbances in energy metabolism in ME/CFS B cells were thus confirmed in a dynamic in vitro model, providing the basis for further mechanistic investigations.


Asunto(s)
Síndrome de Fatiga Crónica , Humanos , Linfocitos B , Metabolismo Energético , Receptores de Antígenos de Linfocitos B , Adyuvantes Inmunológicos , Antígeno CD24
17.
Metabolites ; 12(10)2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36295865

RESUMEN

Nuclear magnetic resonance (NMR) spectroscopy is one of the principal analytical techniques for metabolomics. It has the advantages of minimal sample preparation and high reproducibility, making it an ideal technique for generating large amounts of metabolomics data for biobanks and large-scale studies. Metabolomics is a popular "omics" technology and has established itself as a comprehensive exploratory biomarker tool; however, it has yet to reach its collaborative potential in data collation due to the lack of standardisation of the metabolomics workflow seen across small-scale studies. This systematic review compiles the different NMR metabolomics methods used for serum, plasma, and urine studies, from sample collection to data analysis, that were most popularly employed over a two-year period in 2019 and 2020. It also outlines how these methods influence the raw data and the downstream interpretations, and the importance of reporting for reproducibility and result validation. This review can act as a valuable summary of NMR metabolomic workflows that are actively used in human biofluid research and will help guide the workflow choice for future research.

18.
Pharmacol Biochem Behav ; 221: 173485, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36302442

RESUMEN

The purpose of the present study was to evaluate the efficacy of rapastinel, an allosteric modulator of NMDA receptor function, to accelerate the loss of opioid withdrawal symptoms and blunt or prevent relapse to morphine conditioned place preference (CPP) in rats. Two studies were conducted. In study 1, adult and adolescent male and female rats were treated with increasing doses of morphine (5 mg/kg, bid to 25 mg/kg bid) for 5 days. On day 6 animals were treated with naloxone (1 mg/kg) and withdrawal was assessed. They were then treated with saline or rapastinel (5 mg/kg) on days 6 and 8, and withdrawal was assessed on day 9. Rapastinel treated animals exhibited significantly lower levels of withdrawal signs on day 9. No sex or age differences were observed. In Study 2, CPP for morphine was established in adult rats (males and females) by 4 daily pairings with saline and morphine (am/pm alternation). They were tested for CPP on day 5, and then treated with rapastinel (5 mg/kg) or saline daily on days 6-10 of extinction. On day 11 they received a final dose of rapastinel or saline followed by extinction trial. On day 12, animals received 1 mg/kg of morphine and were tested for relapse. Rapastinel did not affect extinction of CPP, but rapastinel-treated animals spent significantly less time in the previously morphine-paired side than saline-treated animals during the relapse trial. These findings of accelerated loss of withdrawal signs and blunted relapse to CPP suggest that rapastinel could provide an adjunctive therapy for opioid dependence during initiation of pharmacotherapy for opioid dependence.


Asunto(s)
Dependencia de Morfina , Trastornos Relacionados con Opioides , Síndrome de Abstinencia a Sustancias , Femenino , Masculino , Ratas , Animales , Morfina/efectos adversos , Ratas Sprague-Dawley , Recurrencia , Dependencia de Morfina/tratamiento farmacológico
19.
Mol Cancer Res ; 20(6): 841-853, 2022 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-35302608

RESUMEN

Inhibiting androgen signaling using androgen signaling inhibitors (ASI) remains the primary treatment for castrate-resistant prostate cancer. Acquired resistance to androgen receptor (AR)-targeted therapy represents a major impediment to durable clinical response. Understanding resistance mechanisms, including the role of AR expressed in other cell types within the tumor microenvironment, will extend the clinical benefit of AR-targeted therapy. Here, we show the ASI enzalutamide induces vascular catastrophe and promotes hypoxia and microenvironment adaptation. We characterize treatment-induced hypoxia, and subsequent induction of angiogenesis, as novel mechanisms of relapse to enzalutamide, highlighting the importance of two hypoxia-regulated cytokines in underpinning relapse. We confirmed AR expression in CD34+ vascular endothelium of biopsy tissue and human vascular endothelial cells (HVEC). Enzalutamide attenuated angiogenic tubule formation and induced cytotoxicity in HVECs in vitro, and rapidly induced sustained hypoxia in LNCaP xenografts. Subsequent reoxygenation, following prolonged enzalutamide treatment, was associated with increased tumor vessel density and accelerated tumor growth. Hypoxia increased AR expression and transcriptional activity in prostate cells in vitro. Coinhibition of IL8 and VEGF-A restored tumor response in the presence of enzalutamide, confirming the functional importance of their elevated expression in enzalutamide-resistant models. Moreover, coinhibition of IL8 and VEGF-A resulted in a durable, effective resolution of enzalutamide-sensitive prostate tumors. We conclude that concurrent inhibition of two hypoxia-induced factors, IL8 and VEGF-A, prolongs tumor sensitivity to enzalutamide in preclinical models and may delay the onset of enzalutamide resistance. IMPLICATIONS: Targeting hypoxia-induced signaling may extend the therapeutic benefit of enzalutamide, providing an improved treatment strategy for patients with resistant disease.


Asunto(s)
Antagonistas de Receptores Androgénicos , Neoplasias de la Próstata Resistentes a la Castración , Antagonistas de Andrógenos/farmacología , Antagonistas de Receptores Androgénicos/farmacología , Andrógenos/farmacología , Línea Celular Tumoral , Resistencia a Antineoplásicos , Células Endoteliales/metabolismo , Humanos , Hipoxia/tratamiento farmacológico , Interleucina-8/genética , Masculino , Recurrencia Local de Neoplasia/tratamiento farmacológico , Nitrilos/farmacología , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Microambiente Tumoral , Factor A de Crecimiento Endotelial Vascular/genética
20.
J Minim Invasive Gynecol ; 18(1): 123-5, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21195966

RESUMEN

An 18-year-old woman presented with a large right-sided ovarian cyst. After further evaluation and counselling, the patient underwent laparotomy and oophorectomy. The pathology report described a large mature cystic teratoma with a tubular structure consistent with a cross-section of ureter. Subsequent evaluation of the urinary tract system was normal indicating that the ureter was an element of the mature cystic teratoma.


Asunto(s)
Neoplasias Ováricas/patología , Teratoma/patología , Uréter/patología , Adolescente , Femenino , Humanos , Invasividad Neoplásica/patología , Neoplasias Ováricas/cirugía , Ovariectomía , Teratoma/cirugía
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