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1.
Immunity ; 44(4): 875-88, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27096318

RESUMEN

Gut microbiota profoundly affect gut and systemic diseases, but the mechanism whereby microbiota affect systemic diseases is unclear. It is not known whether specific microbiota regulate T follicular helper (Tfh) cells, whose excessive responses can inflict antibody-mediated autoimmunity. Using the K/BxN autoimmune arthritis model, we demonstrated that Peyer's patch (PP) Tfh cells were essential for gut commensal segmented filamentous bacteria (SFB)-induced systemic arthritis despite the production of auto-antibodies predominantly occurring in systemic lymphoid tissues, not PPs. We determined that SFB, by driving differentiation and egress of PP Tfh cells into systemic sites, boosted systemic Tfh cell and auto-antibody responses that exacerbated arthritis. SFB induced PP Tfh cell differentiation by limiting the access of interleukin 2 to CD4(+) T cells, thereby enhancing Tfh cell master regulator Bcl-6 in a dendritic cell-dependent manner. These findings showed that gut microbiota remotely regulated a systemic disease by driving the induction and egress of gut Tfh cells.


Asunto(s)
Artritis/inmunología , Diferenciación Celular/inmunología , Movimiento Celular/inmunología , Microbioma Gastrointestinal/inmunología , Ganglios Linfáticos Agregados/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/inmunología , Linfocitos B/inmunología , Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/inmunología , Células Dendríticas/inmunología , Interleucina-2/inmunología , Subunidad alfa del Receptor de Interleucina-2/genética , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Ganglios Linfáticos Agregados/citología , Proteínas Proto-Oncogénicas c-bcl-6 , Receptores de Antígenos de Linfocitos T/genética , Linfocitos T Colaboradores-Inductores/citología
2.
J Phys Chem A ; 128(8): 1543-1549, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38359462

RESUMEN

Quantum chemical methods dealing with challenging systems while retaining low computational costs have attracted attention. In particular, many efforts have been devoted to developing new methods based on second-order perturbation that may be the simplest correlated method beyond Hartree-Fock. We have recently developed a self-consistent perturbation theory named one-body Møller-Plesset second-order perturbation theory (OBMP2) and shown that it can resolve issues caused by the noniterative nature of standard perturbation theory. In this work, we extend the method by introducing spin-opposite scaling to the double-excitation amplitudes, resulting in the O2BMP2 method. We assess the O2BMP2 performance on the triple-bond N2 dissociation, singlet-triplet gaps, and ionization potentials. O2BMP2 performs much better than standard MP2 and reaches the accuracy of coupled-cluster methods in all cases considered in this work.

3.
Int J Mol Sci ; 25(11)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38892466

RESUMEN

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults, with few effective treatments. EGFR alterations, including expression of the truncated variant EGFRvIII, are among the most frequent genomic changes in these tumors. EGFRvIII is known to preferentially signal through STAT5 for oncogenic activation in GBM, yet targeting EGFRvIII has yielded limited clinical success to date. In this study, we employed patient-derived xenograft (PDX) models expressing EGFRvIII to determine the key points of therapeutic vulnerability within the EGFRvIII-STAT5 signaling axis in GBM. Our findings reveal that exogenous expression of paralogs STAT5A and STAT5B augments cell proliferation and that inhibition of STAT5 phosphorylation in vivo improves overall survival in combination with temozolomide (TMZ). STAT5 phosphorylation is independent of JAK1 and JAK2 signaling, instead requiring Src family kinase (SFK) activity. Saracatinib, an SFK inhibitor, attenuates phosphorylation of STAT5 and preferentially sensitizes EGFRvIII+ GBM cells to undergo apoptotic cell death relative to wild-type EGFR. Constitutively active STAT5A or STAT5B mitigates saracatinib sensitivity in EGFRvIII+ cells. In vivo, saracatinib treatment decreased survival in mice bearing EGFR WT tumors compared to the control, yet in EGFRvIII+ tumors, treatment with saracatinib in combination with TMZ preferentially improves survival.


Asunto(s)
Benzodioxoles , Proliferación Celular , Receptores ErbB , Glioblastoma , Quinazolinas , Factor de Transcripción STAT5 , Temozolomida , Factor de Transcripción STAT5/metabolismo , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/genética , Humanos , Animales , Quinazolinas/farmacología , Quinazolinas/uso terapéutico , Benzodioxoles/farmacología , Benzodioxoles/uso terapéutico , Ratones , Receptores ErbB/metabolismo , Fosforilación/efectos de los fármacos , Línea Celular Tumoral , Temozolomida/farmacología , Proliferación Celular/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Transducción de Señal/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Apoptosis/efectos de los fármacos , Familia-src Quinasas/metabolismo , Proteínas Supresoras de Tumor
4.
Int J Mol Sci ; 24(20)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37894830

RESUMEN

The potential of standard methods of radiation therapy is limited by the dose that can be safely delivered to the tumor, which could be too low for radical treatment. The dose efficiency can be increased by using radiosensitizers. In this study, we evaluated the sensitizing potential of biocompatible iron oxide nanoparticles coated with a dextran shell in A172 and Gl-Tr glioblastoma cells in vitro. The cells preincubated with nanoparticles for 24 h were exposed to ionizing radiation (X-ray, gamma, or proton) at doses of 0.5-6 Gy, and their viability was assessed by the Resazurin assay and by staining of the surviving cells with crystal violet. A statistically significant effect of radiosensitization by nanoparticles was observed in both cell lines when cells were exposed to 35 keV X-rays. A weak radiosensitizing effect was found only in the Gl-Tr line for the 1.2 MeV gamma irradiation and there was no radiosensitizing effect in both lines for the 200 MeV proton irradiation at the Bragg peak. A slight (ca. 10%) increase in the formation of additional reactive oxygen species after X-ray irradiation was found when nanoparticles were present. These results suggest that the nanoparticles absorbed by glioma cells can produce a significant radiosensitizing effect, probably due to the action of secondary electrons generated by the magnetite core, whereas the dextran shell of the nanoparticles used in these experiments appears to be rather stable under radiation exposure.


Asunto(s)
Glioma , Nanopartículas del Metal , Nanopartículas , Fármacos Sensibilizantes a Radiaciones , Humanos , Fármacos Sensibilizantes a Radiaciones/farmacología , Fármacos Sensibilizantes a Radiaciones/química , Dextranos/química , Protones , Glioma/radioterapia , Glioma/patología , Línea Celular Tumoral , Nanopartículas Magnéticas de Óxido de Hierro , Nanopartículas del Metal/química
5.
Antimicrob Agents Chemother ; 66(11): e0032122, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36197095

RESUMEN

Critically ill patients are characterized by substantial pathophysiological changes that alter the pharmacokinetics (PK) of hydrophilic antibiotics, including carbapenems. Meropenem is a key antibiotic for multidrug-resistant Gram-negative bacilli, and such pathophysiological alterations can worsen treatment outcomes. This study aimed to determine the population PK of meropenem and to propose optimized dosing regimens for the treatment of multidrug-resistant Klebsiella pneumoniae in critically ill patients. Two plasma samples were collected from eligible patients over a dosing interval. Nonparametric population PK modeling was performed using Pmetrics. Monte Carlo simulations were applied to different dosing regimens to determine the probability of target attainment and the cumulative fraction of response, taking into account the local MIC distribution for K. pneumoniae. The targets of 40% and 100% for the fraction of time that free drug concentrations remained above the MIC (ƒT>MIC) were tested, as suggested for critically ill patients. A one-compartment PK model using data from 27 patients showed high interindividual variability. Significant PK covariates were the 8-h creatinine clearance for meropenem and the presence of an indwelling catheter for pleural, abdominal, or cerebrospinal fluid drainage for the meropenem volume of distribution. The target 100% ƒT>MIC for K. pneumoniae, with a MIC of ≤2 mg/liter, could be attained by the use of a continuous infusion of 2.0 g/day. Meropenem therapy in critically ill patients could be optimized for K. pneumoniae isolates with an MIC of ≤2 mg/liter by using a continuous infusion in settings with more than 50% isolates have a MIC of ≥32mg/L.


Asunto(s)
Enfermedad Crítica , Klebsiella pneumoniae , Humanos , Meropenem/farmacocinética , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Método de Montecarlo
6.
Nucleic Acids Res ; 48(19): 11068-11082, 2020 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-33035335

RESUMEN

tRNAs play a central role during the translation process and are heavily post-transcriptionally modified to ensure optimal and faithful mRNA decoding. These epitranscriptomics marks are added by largely conserved proteins and defects in the function of some of these enzymes are responsible for neurodevelopmental disorders and cancers. Here, we focus on the Trm11 enzyme, which forms N2-methylguanosine (m2G) at position 10 of several tRNAs in both archaea and eukaryotes. While eukaryotic Trm11 enzyme is only active as a complex with Trm112, an allosteric activator of methyltransferases modifying factors (RNAs and proteins) involved in mRNA translation, former studies have shown that some archaeal Trm11 proteins are active on their own. As these studies were performed on Trm11 enzymes originating from archaeal organisms lacking TRM112 gene, we have characterized Trm11 (AfTrm11) from the Archaeoglobus fulgidus archaeon, which genome encodes for a Trm112 protein (AfTrm112). We show that AfTrm11 interacts directly with AfTrm112 similarly to eukaryotic enzymes and that although AfTrm11 is active as a single protein, its enzymatic activity is strongly enhanced by AfTrm112. We finally describe the first crystal structures of the AfTrm11-Trm112 complex and of Trm11, alone or bound to the methyltransferase inhibitor sinefungin.


Asunto(s)
Proteínas Arqueales , Archaeoglobus fulgidus/enzimología , ARN de Archaea/metabolismo , ARN de Transferencia/metabolismo , ARNt Metiltransferasas , Proteínas Arqueales/química , Proteínas Arqueales/metabolismo , Modelos Moleculares , Estructura Molecular , Unión Proteica , Conformación Proteica , Procesamiento Proteico-Postraduccional , ARNt Metiltransferasas/química , ARNt Metiltransferasas/metabolismo
7.
Adv Exp Med Biol ; 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35389201

RESUMEN

INTRODUCTION: In recent years, both stromal vascular fraction (SVF) from adipose tissue and mesenchymal stem cells (MSC) from adipose tissues were extensively used in both preclinical and clinical treatment for various diseases. Some studies reported differences in treatment efficacy between SVFs and MSCs in animals as well as in humans. Therefore, this study is aimed to evaluate the immune modulation and angiogenic potential of SVFs and MSCs from the same SVF samples to support an explanation when SVFs or MSCs should be used. METHODS: The adipose tissue samples from ten female donors with consent forms were collected. SVFs from these samples were isolated according to the published protocols. The existence of mesenchymal cells that positive with CD44, CD73, CD90, and CD105 and endothelial progenitor cells that positive with CD31 and CD34 was determined using flow cytometry. Three samples of SVFs with similar percentages of mesenchymal cell portion and endothelial progenitor cell portion were used to isolate MSCs. Obtained MSCs were confirmed as MSCs using the ISCT minimal criteria. To compare the immune modulation of SVF and MSCs, the mixed lymphocyte assay was used. The lymphocyte proliferation, as well as IFN-gamma and TNF-alpha concentrations, were determined. To compare the angiogenic potential, the angiogenesis in quail embryo assay was used. The angiogenesis efficacy was measured based on the vessel areas formed in the embryos after 7 days. RESULTS: The results showed that all SVF samples contained the portions of mesenchymal cells and endothelial progenitor cells. MSCs from SVFs meet all minimal criteria of MSCs that suggested by ISCT. MSCs from SVFs efficiently suppressed the immune cell proliferation compared to the SVFs, especially at ratios of 1:4 (1 MSCs: 4 immune cells). MSCs also inhibited the IFN-gamma and TNF-alpha production more efficiently than SVFs (p < 0.05). However, in quail embryo models, SVFs triggered the angiogenesis and neovessel formation better than MSCs with more significant vessel areas after 7 days (p < 0.05). CONCLUSION: This study suggested that SVFs and MSCs have different potentials for immune modulation and angiogenesis. SVFs help the angiogenesis better than MSCs, while MSCs displayed the more significant immune modulation. These results can guide the usage of SVFs or MSCs in disease treatment.

8.
Medicina (Kaunas) ; 58(2)2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35208549

RESUMEN

Obstructive sleep apnea (OSA) remains a prominent disease state characterized by the recurrent collapse of the upper airway while sleeping. To date, current treatment may include continuous positive airway pressure (CPAP), lifestyle changes, behavioral modification, mandibular advancement devices, and surgical treatment. However, due to the desire for a more convenient mode of management, pharmacological treatment has been thoroughly investigated as a means for a potential alternative in OSA treatment. OSA can be distinguished into various endotypic or phenotypic classes, allowing pharmacological treatment to better target the root cause or symptoms of OSA. Some medications available for use include antidepressants, CNS stimulants, nasal decongestants, carbonic anhydrase inhibitors, and potassium channel blockers. This review will cover the findings of currently available and future study medications that could potentially play a role in OSA therapy.


Asunto(s)
Avance Mandibular , Apnea Obstructiva del Sueño , Presión de las Vías Aéreas Positiva Contínua , Humanos , Ferulas Oclusales , Sueño , Apnea Obstructiva del Sueño/tratamiento farmacológico
9.
Glia ; 69(9): 2199-2214, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33991013

RESUMEN

High-grade gliomas (HGGs) are aggressive, treatment-resistant, and often fatal human brain cancers. The TNF-like weak inducer of apoptosis (TWEAK)/fibroblast growth factor-inducible 14 (Fn14) signaling axis is involved in tissue repair after injury and constitutive signaling has been implicated in the pathogenesis of numerous solid cancers. The Fn14 gene is expressed at low levels in the normal, uninjured brain but is highly expressed in primary isocitrate dehydrogenase wild-type and recurrent HGGs. Fn14 signaling is implicated in numerous aspects of glioma biology including brain invasion and chemotherapy resistance, but whether Fn14 overexpression can directly promote tumor malignancy has not been reported. Here, we used the replication-competent avian sarcoma-leukosis virus/tumor virus A system to examine the impact of Fn14 expression on glioma development and pathobiology. We found that the sole addition of Fn14 to an established oncogenic cocktail previously shown to generate proneural-like gliomas led to the development of highly invasive and lethal brain cancer with striking biological features including extensive pseudopalisading necrosis, constitutive canonical and noncanonical NF-κB pathway signaling, and high plasminogen activator inhibitor-1 (PAI-1) expression. Analyses of HGG patient datasets revealed that high human PAI-1 gene (SERPINE1) expression correlates with shorter patient survival, and that the SERPINE1 and Fn14 (TNFRSF12A) genes are frequently co-expressed in bulk tumor tissues, in tumor subregions, and in malignant cells residing in the tumor microenvironment. These findings provide new insights into the potential importance of Fn14 in human HGG pathobiology and designate both the NF-κB signaling node and PAI-1 as potential targets for therapeutic intervention. MAIN POINTS: This work demonstrates that elevated levels of the TWEAK receptor Fn14 in tumor-initiating, neural progenitor cells leads to the transformation of proneural-like gliomas into more aggressive and lethal tumors that exhibit constitutive NF-κB pathway activation and plasminogen activator inhibitor-1 overexpression.


Asunto(s)
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Factores de Crecimiento de Fibroblastos , Glioma/patología , Humanos , Invasividad Neoplásica , Receptores del Factor de Necrosis Tumoral/genética , Receptores del Factor de Necrosis Tumoral/metabolismo , Receptor de TWEAK , Microambiente Tumoral
10.
Mol Med ; 27(1): 28, 2021 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33765907

RESUMEN

BACKGROUND: Glioblastoma is the most common primary brain tumor and remains uniformly fatal, highlighting the dire need for developing effective therapeutics. Significant intra- and inter-tumor heterogeneity and inadequate delivery of therapeutics across blood-brain barrier continue to be significant impediments towards developing therapies which can significantly enhance survival. We hypothesize that microRNAs have the potential to serve as effective therapeutics for glioblastoma as they modulate the activity of multiple signaling pathways, and hence can counteract heterogeneity if successfully delivered. METHODS: Using a computational approach, we identified microRNA-34a as a microRNA that maximally reduces the activation status of the three core signaling networks (the receptor tyrosine kinase, p53 and Rb networks) that have been found to be deregulated in most glioblastoma tumors. Glioblastoma cultures were transfected with microRNA-34a or control microRNA to assess biological function and therapeutic potential in vitro. Nanocells were derived from genetically modified bacteria and loaded with microRNA-34a for intravenous administration to orthotopic patient-derived glioblastoma xenografts in mice. RESULTS: Overexpression of microRNA-34a strongly reduced the activation status of the three core signaling networks. microRNA-34a transfection also inhibited the survival of multiple established glioblastoma cell lines, as well as primary patient-derived xenograft cultures representing the proneural, mesenchymal and classical subtypes. Transfection of microRNA-34a enhanced temozolomide (TMZ) response in in vitro cultures of glioblastoma cells with primary TMZ sensitivity, primary TMZ resistance and acquired TMZ resistance. Mechanistically, microRNA-34a downregulated multiple therapeutic resistance genes which are associated with worse survival in glioblastoma patients and are enriched in specific tumor spatial compartments. Importantly, intravenous administration of nanocells carrying miR-34a and targeted to epidermal growth factor receptor (EGFR) strongly enhanced TMZ sensitivity in an orthotopic patient-derived xenograft mouse model of glioblastoma. CONCLUSIONS: Targeted bacterially-derived nanocells are an effective vehicle for the delivery of microRNA-34a to glioblastoma tumors. microRNA-34a inhibits survival and strongly sensitizes a wide range of glioblastoma cell cultures to TMZ, suggesting that combination therapy of TMZ with microRNA-34a loaded nanocells may serve as a novel therapeutic approach for the treatment of glioblastoma tumors.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , MicroARNs/administración & dosificación , Nanoestructuras/administración & dosificación , Temozolomida/uso terapéutico , Animales , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/genética , Humanos , Ratones Desnudos
11.
Am J Pathol ; 190(10): 2165-2176, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32693062

RESUMEN

Glioblastoma (GBM) is the most common primary malignant brain cancer in adults. A hallmark of GBM is aggressive invasion of tumor cells into the surrounding normal brain. Both the current standard of care and targeted therapies have largely failed to specifically address this issue. Therefore, identifying key regulators of GBM cell migration and invasion is important. The leukemia-associated Rho guanine nucleotide exchange factor (LARG) has previously been implicated in cell invasion in other tumor types; however, its role in GBM pathobiology remains undefined. Herein, we report that the expression levels of LARG and ras homolog family members C (RhoC), and A (RhoA) increase with glial tumor grade and are highest in GBM. LARG and RhoC protein expression is more prominent in invading cells, whereas RhoA expression is largely restricted to cells in the tumor core. Knockdown of LARG by siRNA inhibits GBM cell migration in vitro and invasion ex vivo in organotypic brain slices. Moreover, siRNA-mediated silencing of RhoC suppresses GBM cell migration in vitro and invasion ex vivo, whereas depletion of RhoA enhances GBM cell migration and invasion, supporting a role for LARG and RhoC in GBM cell migration and invasion. Depletion of LARG increases the sensitivity of GBM cells to temozolomide treatment. Collectively, these results suggest that LARG and RhoC may represent unappreciated targets to inhibit glioma invasion.


Asunto(s)
Movimiento Celular/fisiología , Glioblastoma/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Proteína rhoC de Unión a GTP/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Humanos , Transducción de Señal/fisiología
12.
J Vasc Surg ; 74(4): 1117-1124, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33848555

RESUMEN

OBJECTIVE: Symptomatic and ruptured abdominal aortic aneurysms (AAAs) are increasingly being managed with endovascular aneurysm repair (EVAR). We aimed to identify the outcomes of symptomatic and ruptured AAAs that had undergone EVAR with a chimney or snorkel technique (ChEVAR). METHODS: A retrospective cohort study was performed using the Vascular Quality Initiative registry from March 2013 to July 2019. All patients with symptomatic and ruptured AAAs with a proximal aortic zone of disease from 6 to 9 who had undergone ChEVAR were included. The outcomes were analyzed in accordance with the Society for Vascular Surgery reporting standards for EVAR. RESULTS: ChEVAR was performed in 77 patients (ruptured, 35 [45.5%]; symptomatic, 42 [54.5%]). The median age was 73.0 years (interquartile range [IQR], 67.0-81.0 years), and 54 patients (70.1%) were men. The median maximum aneurysm diameter was 67.5 mm (IQR, 54.5-83.3 mm). All patients had American Society of Anesthesiologists class ≥III. For the patients with ruptured AAAs, the mean lowest preoperative systolic blood pressure was 95.3 ± 29.3 mm Hg. The fluoroscopy time was 57.4 minutes (IQR, 41.2-79.0 minutes). The proximal aortic zone of disease was zone 6 in 9 (11.7%), zone 7 in 21 (27.3%), zone 8 in 36 (46.8%), and zone 9 in 11 (14.3%) patients. ChEVAR involved more than one vessel in 55 patients (71.4%). No significant difference was found in 30-day mortality between the patients with ruptured vs symptomatic AAAs (11.4% vs 7.1%; P = .695). Reintervention was required for 10 patients (13.0%) at a median of 9 postoperative days, 2 (20.0%) of whom died. Postoperatively, 31 patients (40.3%) had experienced a major complication. A type I endoleak had occurred in nine patients (11.7%), two (22.2%) of whom died. Long-term follow-up data were available for 38 patients (49.4%) at a median of 406.5 days (IQR, 326.8-602.0 days) postoperatively. Of the 18 patients with long-term radiographic data, sac growth was detected in 4 (22.2%). A total of 14 patients had died at a median of 26.5 days (IQR, 3.0-468.5 days). CONCLUSIONS: ChEVAR for symptomatic and ruptured AAAs can be performed with acceptable rates of morbidity and mortality. Long-term data are needed to determine the durability.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Rotura de la Aorta/cirugía , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/mortalidad , Rotura de la Aorta/diagnóstico por imagen , Rotura de la Aorta/mortalidad , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/mortalidad , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Masculino , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/terapia , Sistema de Registros , Retratamiento , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
13.
J Hum Evol ; 161: 103075, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34655947

RESUMEN

Tam Pà Ling, a cave site in northeastern Laos, has yielded the earliest skeletal evidence of Homo sapiens in mainland Southeast Asia. The reliance of Pleistocene humans in rainforest settings on plant or animal resources is still largely unstudied, mainly due to poor collagen preservation in fossils from tropical environments precluding stable nitrogen isotope analysis, the classical trophic level proxy. However, isotopic ratios of zinc (Zn) in bioapatite constitute a promising proxy to infer trophic and dietary information from fossil vertebrates, even under adverse tropical taphonomic conditions. Here, we analyzed the zinc isotope composition (66Zn/64Zn expressed as δ66Zn value) in the enamel of two teeth of the Late Pleistocene (63-46 ka) H. sapiens individual (TPL1) from Tam Pà Ling, as well as 76 mammal teeth from the same site and the nearby Nam Lot cave. The human individual exhibits relatively low enamel δ66Zn values (+0.24‰) consistent with an omnivorous diet, suggesting a dietary reliance on both plant and animal matter. These findings offer direct evidence of the broad utilization of resources from tropical rainforests by one of the earliest known anatomically modern humans in Southeast Asia.


Asunto(s)
Hominidae , Isótopos de Zinc , Animales , Asia Sudoriental , Isótopos de Carbono/análisis , Fósiles , Humanos , Isótopos de Nitrógeno/análisis , Isótopos de Zinc/análisis
14.
J Endovasc Ther ; 28(4): 567-574, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33970044

RESUMEN

PURPOSE: Percutaneous lower extremity revascularization is being performed via upper extremity, pedal, or popliteal access with increasing frequency. This study aimed to compare periprocedural outcomes of popliteal (POA) and upper extremity (UEA) access for the treatment of isolated superficial femoral artery (SFA) occlusive disease. MATERIALS AND METHODS: A retrospective cohort study compared the outcomes of patients undergoing primary percutaneous intervention of SFA occlusive disease with POA or UEA using the Vascular Quality Initiative database from December 2010 to June 2019. Our primary endpoint was technical success. Secondary endpoints included factors associated with perioperative complications. RESULTS: A total of 349 patients underwent isolated SFA intervention through the popliteal, radial, or brachial artery. UEA was performed in 188 (53.9%) patients and POA in 161 (46.1%). Technical success with TASC A lesions was 95.8% and with TASC D lesions, 65.0%. POA had a higher proportion of TASC D lesions (24.8% vs 10.6%, p<0.001), and larger (≥7 Fr) sheath size (14.3% vs 2.7%, p<0.001). UEA had a higher proportion of no calcification (27.1% vs 11.2%, p<0.001), and smaller (4-5 Fr) sheath size (46.8% vs 34.8%, p=0.023). There was no difference in technical success between UEA and POA (88.8% vs 84.5%, p=0.230), which was also seen on multivariable analysis (p=0.985). Univariate analysis revealed technical failure was associated with TASC D lesions (45.7% vs 12.9%, p<0.001) and the presence of severe calcifications (39.1% vs 17.5%, p=0.002). Multivariable analysis confirmed technical failure was associated with degree of calcification (OR, 2.4; 95% CI, 1.18 to 4.89; p=0.016) and TASC D lesions (OR, 5.01; 95% CI, 2.45 to 10.24; p<0.001). Postoperative complications were associated with UEA on univariate (p=0.041) and multivariate analysis (OR, 2.08; 95% CI, 0.80 to 5.37; p=0.016). Access site complications were also associated with UEA compared to POA (4.3% vs 0.0%, p=0.027). CONCLUSIONS: There is no difference in technical success between UEA and POA when treating isolated SFA occlusive disease, and UEA is associated with a higher complication rate. Technical success is dependent on calcification and TASC II classification. Based on similar technical success rates and low complication rates, POA should be considered as a viable alternative to UEA when planning endovascular interventions.


Asunto(s)
Arteriopatías Oclusivas , Arteria Femoral , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/cirugía , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Humanos , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/cirugía , Estudios Retrospectivos , Stents , Resultado del Tratamiento , Extremidad Superior , Grado de Desobstrucción Vascular
15.
Ann Vasc Surg ; 72: 529-534, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32927045

RESUMEN

BACKGROUND: Patients with critical limb ischemia (CLI) often require lower extremity bypass surgery for limb salvage. A myocardial infarction (MI) is a major postoperative risk. Our objective is to assess the utility of preoperative stress test in determining patient outcomes. METHODS: This is a retrospective study utilizing the national Vascular Quality Initiative database. We collected data from 2013-2018 on all patients undergoing lower extremity bypass for CLI and assessed whether or not they had a preoperative stress test. Rates of an MI were then compared between groups of patients who either did not receive a stress test, had a normal stress test or a positive stress test. An MI was distinguished as troponin only and electrocardiogram (EKG)/clinical. Our secondary end point was in-hospital mortality. Univariate and multivariate analysis with the stress test as a covariate was used to determine significance. RESULTS: During this time period, 29,937 bypasses were performed on 27,219 patients. The average age was 67.5 years (±11.09), 66.3% were men, and 17.3% were African American. Risk factors included hypertension (89.5%), diabetes (55.9%), congestive heart failure (20%), coronary artery disease (32.5%), coronary artery bypass graft (22.2%), and percutaneous coronary intervention (21%). 19,108 patients (64.1%) did not undergo the stress test before bypass, 6,830 (22.9%) had a normal stress test, and 2,898 (9.7%) had a positive stress test. Overall rate of an MI was 4%, with 2% being troponin only and 2% EKG/clinical. The positive stress test had a higher rate of troponin only (2.85%) as well as EKG/clinical (3.37%) MI. For every 10 year increase in age, the odds of having a postoperative MI increased by 27% (P < 0.0001). Overall in-hospital mortality was 1.4%. Patients with positive stress tests had a 2.6% mortality compared with normal/not performed at 1.3%. Of the patients who died, 21.5% had an EKG/clinical MI. Of those patients, 50% did not have a stress test, 12% had normal stress tests, and 23% had positive stress tests. When comparing rates of patients who died or had an MI, there was no difference between patients who had no or a normal stress test (7.29%) versus those who had a positive stress test (7.58%), (P = 0.11). CONCLUSIONS: A positive stress test before lower extremity bypass is a significant predictor of a postoperative MI. However, mortality increase was minimal in patients with a positive stress test. Therefore, the stress test result should not delay care for patients needing urgent revascularization.


Asunto(s)
Prueba de Esfuerzo , Isquemia/cirugía , Extremidad Inferior/irrigación sanguínea , Infarto del Miocardio/epidemiología , Isquemia Miocárdica/diagnóstico , Enfermedad Arterial Periférica/cirugía , Procedimientos Quirúrgicos Vasculares/efectos adversos , Anciano , Comorbilidad , Enfermedad Crítica , Bases de Datos Factuales , Electrocardiografía , Femenino , Mortalidad Hospitalaria , Humanos , Isquemia/diagnóstico por imagen , Isquemia/mortalidad , Recuperación del Miembro , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/mortalidad , Isquemia Miocárdica/mortalidad , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/mortalidad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/mortalidad
16.
Nucleic Acids Res ; 47(15): 7719-7733, 2019 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-31328227

RESUMEN

N6-methyladenosine (m6A) has recently been found abundantly on messenger RNA and shown to regulate most steps of mRNA metabolism. Several important m6A methyltransferases have been described functionally and structurally, but the enzymes responsible for installing one m6A residue on each subunit of human ribosomes at functionally important sites have eluded identification for over 30 years. Here, we identify METTL5 as the enzyme responsible for 18S rRNA m6A modification and confirm ZCCHC4 as the 28S rRNA modification enzyme. We show that METTL5 must form a heterodimeric complex with TRMT112, a known methyltransferase activator, to gain metabolic stability in cells. We provide the first atomic resolution structure of METTL5-TRMT112, supporting that its RNA-binding mode differs distinctly from that of other m6A RNA methyltransferases. On the basis of similarities with a DNA methyltransferase, we propose that METTL5-TRMT112 acts by extruding the adenosine to be modified from a double-stranded nucleic acid.


Asunto(s)
Adenosina/química , Regulación Neoplásica de la Expresión Génica , Metiltransferasas/química , ARN Mensajero/química , ARN Ribosómico 18S/química , Adenosina/genética , Adenosina/metabolismo , Secuencia de Bases , Sitios de Unión , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas , Línea Celular Tumoral , Cristalografía por Rayos X , Eliminación de Gen , Células HCT116 , Humanos , Metiltransferasas/genética , Metiltransferasas/metabolismo , Modelos Moleculares , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Estabilidad Proteica , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Ribosómico 18S/genética , ARN Ribosómico 18S/metabolismo , Transducción de Señal , Especificidad por Sustrato
17.
Health Res Policy Syst ; 19(Suppl 2): 44, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34380491

RESUMEN

BACKGROUND: One Health approaches such as the Joint human and animal vaccination programmes (JHAVP) are shown to be feasible and to increase health care access to hard-to-reach communities such as mobile pastoralists. However, the financial sustainability and the integration into the public health systems at the district level of such programmes are still challenging. The main objective of the present study was to give insight to the feasibility and financial sustainability of JHAVP integrated as part of the public health system in Chad. METHODS: We conducted a mixed methods study using semi-structured key informant interviews, focus group discussions and budget impact analysis. Strengths, weaknesses, opportunities, and threats were analysed regarding the feasibility and sustainability of the implementation of JHAVP in Danamadji health district in Chad. Feasibility was further analysed using three dimensions: acceptability, implementation, and adaptation. Financial sustainability of JHAVP was analysed through budget impact analysis of implementation of the programme at district level. RESULTS: The acceptability of this approach was regularly assessed by immunization campaign teams through evaluation meetings which included pastoralists. The presence of authorities in the meetings and workshops of the programme had an incentive effect since they represent a mark of consideration these populations generally declared to be lacking. The coordination between the public health and veterinary services at central and decentralized level seemed to be a key element in the success of the implementation of the programme. Regarding financial sustainability, the total incremental budget impact was 27% slightly decreasing to 26% after five years, which accounts for up to one third of the total budget of the district health office. Also, given that most of the costs for each round are recurrent costs, efficiency gains from scale effects over time are limited. CONCLUSION: Based on these findings, we conclude that for JHAVP to be routinely delivered at the district health level, a considerable increase in financial resources would be required. The district could benefit from joint immunization to maintain contact with mobile pastoralists to promote the use of available immunization services at district level.


Asunto(s)
Inmunización , Salud Pública , Animales , Chad , Estudios de Factibilidad , Humanos , Vacunación
18.
Health Res Policy Syst ; 19(Suppl 2): 52, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34380523

RESUMEN

BACKGROUND: In 2006, Uganda adopted the Reaching Every District strategy with the goal of attaining at least 80% coverage for routine immunizations in every district. The development and utilization of health facility/district immunization microplans is the key to the strategy. A number of reports have shown suboptimal development and use of microplans in Uganda. This study explores factors associated with suboptimal development and use of microplans in two districts in Uganda to pinpoint challenges encountered during the microplanning process. METHODS: A qualitative study was conducted comparing two districts: Kapchorwa, with low immunization coverage, and Luwero with high immunization coverage. Data were collected through multilevel observation of health facilities, planning sessions and planning meetings; records review of microplans, micromaps and meeting minutes; 57 interviews with health workers at the ministry level and lower-level health facility workers. Data were analysed using NVivo 8 qualitative text analysis software. Transcripts were coded, and memos and display matrices were developed to examine the process of developing and utilizing microplans, including experiences of health workers (implementers). RESULTS: Three key findings emerged from this study. First, there are significant knowledge gaps with regard to the microplanning process among health workers at all levels (community and district health facility and nationally). Limited knowledge about communities and programme catchment areas greatly hinders the planning process by limiting the ability to identify hard-to-reach areas and to prioritize areas according to need. Secondly, the microplanning tool is bulky and complex. Finally, microplanning is being implemented in the context of already overtasked health personnel who have to conduct several other activities as part of their daily routines. CONCLUSIONS: In order to achieve quality improvement as outlined in the Reaching Every District campaign, the microplanning process should be revised. Health workers' misunderstanding and limited knowledge about the microplanning process, especially at peripheral health facilities, coupled with the complex, bulky nature of the microplanning tool, reduces the effectiveness of microplanning in improving routine immunization in Uganda. This study reveals the need to reduce the complexity of the tool and to identify ways to train and support workers in the use of the revised tool, including support in incorporating the microplanning process into their busy schedules.


Asunto(s)
Inmunización , Vacunación , Instituciones de Salud , Humanos , Programas de Inmunización , Uganda
19.
Bioinformatics ; 35(19): 3812-3814, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30825371

RESUMEN

SUMMARY: We present MetaMarker, a pipeline for discovering metagenomic biomarkers from whole-metagenome sequencing samples. Different from existing methods, MetaMarker is based on a de novo approach that does not require mapping raw reads to a reference database. We applied MetaMarker on whole-metagenome sequencing of colorectal cancer (CRC) stool samples from France to discover CRC specific metagenomic biomarkers. We showed robustness of the discovered biomarkers by validating in independent samples from Hong Kong, Austria, Germany and Denmark. We further demonstrated these biomarkers could be used to build a machine learning classifier for CRC prediction. AVAILABILITY AND IMPLEMENTATION: MetaMarker is freely available at https://bitbucket.org/mkoohim/metamarker under GPLv3 license. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Metagenoma , Biomarcadores de Tumor , Neoplasias Colorrectales , Bases de Datos Factuales , Humanos , Metagenómica , Programas Informáticos
20.
J Vasc Surg ; 72(1): 144-153, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31831312

RESUMEN

INTRODUCTION: Open abdominal aortic aneurysm (oAAA) repair in the era of advanced endovascular aortic techniques is used in challenging anatomy. The impact of the location of the proximal aortic cross-clamp (suprarenal [SR] vs infrarenal [IR]) on outcomes remains to be determined. The aim of this study was to analyze the effect of proximal aortic cross-clamp location on short-term and overall survival after oAAA repair in a contemporary series. METHODS: A retrospective cohort study was performed comparing the outcomes of patients undergoing oAAA repair with SR and IR aortic cross-clamping using the Vascular Quality Initiative registry from January 2003 to September 2018. Our primary end point was short-term mortality. RESULTS: There were 7601 patients who underwent oAAA repair. Their mean age was 69.3 ± 8.5 years and 5555 patients (73.1%) were male. The aortic cross-clamp location was IR in 4044 patients (53.2%). The SR group had increased maximum AAA diameter (58 mm vs 56 mm; P < .0001), hypertension (85.5% vs 82.0%; P < .0001), preoperative creatinine (1.11 vs 1.08; P = .001), and were more likely to be in American Society of Anesthesiologists class IV (37.4% vs 30.6%; P < .0001). Postoperative renal failure occurred significantly more often in the SR group (24.4 vs 11.4%; P < .0001). Short-term mortality was 2.7% in the IR group and 4.7% in the SR group (P < .0001). Kaplan-Meier survival estimates were 93.7% and 83.8% in the IR group and 90.9% and 81.2% in the SR group at 1 and 5 years, respectively (P = .007). Multivariable analysis demonstrated that SR cross-clamping was significantly associated with short-term mortality (hazard ratio, 1.38; 95% confidence interval, 1.07-1.78; P = .01); however, it did not affect overall survival (hazard ratio, 1.13; 95% confidence interval, 1.00-1.28; P = .06). CONCLUSIONS: A SR cross-clamp location is associated with an increased short-term mortality in patients undergoing oAAA repair. Overall survival is not affected by a SR cross-clamp location.


Asunto(s)
Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/cirugía , Procedimientos Quirúrgicos Vasculares , Anciano , Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/mortalidad , Constricción , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos , Procedimientos Quirúrgicos Vasculares/mortalidad
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