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1.
J Chem Phys ; 160(17)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38748001

RESUMEN

In this work, we introduce variational umbrella seeding, a novel technique for computing nucleation barriers. This new method, a refinement of the original seeding approach, is far less sensitive to the choice of order parameter for measuring the size of a nucleus. Consequently, it surpasses seeding in accuracy and umbrella sampling in computational speed. We test the method extensively and demonstrate excellent accuracy for crystal nucleation of nearly hard spheres and two distinct models of water: mW and TIP4P/ICE. This method can easily be extended to calculate nucleation barriers for homogeneous melting, condensation, and cavitation.

2.
Neurosurg Focus ; 56(5): E9, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38691864

RESUMEN

OBJECTIVE: Chordomas are rare tumors of the skull base and spine believed to arise from the vestiges of the embryonic notochord. These tumors are locally aggressive and frequently recur following resection and adjuvant radiotherapy. Proton therapy has been introduced as a tissue-sparing option because of the higher level of precision that proton-beam techniques offer compared with traditional photon radiotherapy. This study aimed to compare recurrence in patients with chordomas receiving proton versus photon radiotherapy following resection by applying tree-based machine learning models. METHODS: The clinical records of all patients treated with resection followed by adjuvant proton or photon radiotherapy for chordoma at Mayo Clinic were reviewed. Patient demographics, type of surgery and radiotherapy, tumor recurrence, and other variables were extracted. Decision tree classifiers were trained and tested to predict long-term recurrence based on unseen data using an 80/20 split. RESULTS: Fifty-three patients with a mean ± SD age of 55.2 ± 13.4 years receiving surgery and adjuvant proton or photon therapy to treat chordoma were identified; most patients were male. Gross-total resection was achieved in 54.7% of cases. Proton therapy was the most common adjuvant radiotherapy (84.9%), followed by conventional or external-beam radiation therapy (9.4%) and stereotactic radiosurgery (5.7%). Patients receiving proton therapy exhibited a 40% likelihood of having recurrence, significantly lower than the 88% likelihood observed in those treated with nonproton therapy. This was confirmed on logistic regression analysis adjusted for extent of tumor resection and tumor location, which revealed that proton adjuvant radiotherapy was associated with a decreased risk of recurrence (OR 0.1, 95% CI 0.01-0.71; p = 0.047) compared with photon therapy. The decision tree algorithm predicted recurrence with an accuracy of 90% (95% CI 55.5%-99.8%), with the lowest risk of recurrence observed in patients receiving gross-total resection with adjuvant proton therapy (23%). CONCLUSIONS: Following resection, adjuvant proton therapy was associated with a lower risk of chordoma recurrence compared with photon therapy. The described machine learning models were able to predict tumor progression based on the extent of tumor resection and adjuvant radiotherapy modality used.


Asunto(s)
Cordoma , Recurrencia Local de Neoplasia , Fotones , Terapia de Protones , Neoplasias de la Columna Vertebral , Humanos , Cordoma/radioterapia , Cordoma/cirugía , Masculino , Femenino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/radioterapia , Terapia de Protones/métodos , Radioterapia Adyuvante/métodos , Adulto , Anciano , Neoplasias de la Columna Vertebral/radioterapia , Neoplasias de la Columna Vertebral/cirugía , Fotones/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento
3.
J Clin Neurosci ; 124: 109-114, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38696975

RESUMEN

INTRODUCTION: The prevalence of intracranial aneurysms (IA) in patients with acute ischemic stroke (AIS) requiring mechanical thrombectomy (MT) is unclear. OBJECTIVE: To describe the prevalence of IA in patients with AIS and their influence on MT. MATERIALS & METHODS: This is a retrospective cohort study on all patients admitted with a diagnosis of AIS from January 2008 to March 2022 at a tertiary academic center. The records were reviewed for demographic, clinical, imaging, and outcomes data. Only patients who had CTA at admission were included in this analysis. RESULTS: Among 2265 patients admitted with AIS, this diagnosis was confirmed in 2113 patients (93.3 %). We included 1111 patients (52.6 %) who had head CTA and 321 (28.9 %) who underwent MT. The observed prevalence of aneurysms on CTA was 4.5 % (50/1111 patients), and 8 (16 %) had multiple aneurysms. MT was performed in 7 patients harboring IAs: 6 ipsilateral (5 proximal and 1 distal to the occlusion)and 1 contralateral aneurysm.. The patient with a contralateral aneurysm had a TICI 2B score In patients with ipsilateral aneurysms, TICI 2B or 3 was achieved in 3 cases (50 %), which is significantly lower than historical control of MT (91.6 %) without IA (p = 0.01). No aneurysms ruptured during MT. The aneurysm noted distal to the occlusion was mycotic. CONCLUSION: In this analysis, the observed prevalence of IA in patients with AIS was 4.5%. Ipsilateral aneurysms (proximal or distal to the occlusion site) deserve particular attention, given the potential risk of rupture during MT. Aneurysms located distal to the occlusion were mycotic and the rate of recanization in patients with ipsilateral aneurysms was low compared to historical controls. Further studies are needed to improve the outcomes in patients with IA requiring MT.


Asunto(s)
Aneurisma Intracraneal , Accidente Cerebrovascular Isquémico , Centros de Atención Terciaria , Trombectomía , Humanos , Aneurisma Intracraneal/epidemiología , Aneurisma Intracraneal/cirugía , Aneurisma Intracraneal/complicaciones , Masculino , Femenino , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/cirugía , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Prevalencia , Trombectomía/métodos , Anciano de 80 o más Años
4.
J Phys Chem Lett ; 15(16): 4477-4485, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38634502

RESUMEN

Non-polarizable force fields fail to accurately predict free energies of aqueous electrolytes without compromising the predictive ability for densities and transport properties. A new approach is presented in which (1) TIP4P/2005 water and scaled charge force fields are used to describe the interactions in the liquid phase and (2) an additional Effective Charge Surface (ECS) is used to compute free energies at zero additional computational expense. The ECS is obtained using a single temperature-independent charge scaling parameter per species. Thereby, the chemical potential of water and the free energies of hydration of various aqueous salts (e.g., NaCl and LiCl) are accurately described (deviations less than 5% from experiments), in sharp contrast to calculations where the ECS is omitted (deviations larger than 20%). This approach enables accurate predictions of free energies of aqueous electrolyte solutions using non-polarizable force fields, without compromising liquid-phase properties.

5.
Database (Oxford) ; 20242024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38537198

RESUMEN

Curation of biomedical knowledge into systems biology diagrammatic or computational models is essential for studying complex biological processes. However, systems-level curation is a laborious manual process, especially when facing ever-increasing growth of domain literature. New findings demonstrating elaborate relationships between multiple molecules, pathways and cells have to be represented in a format suitable for systems biology applications. Importantly, curation should capture the complexity of molecular interactions in such a format together with annotations of the involved elements and support stable identifiers and versioning. This challenge calls for novel collaborative tools and platforms allowing to improve the quality and the output of the curation process. In particular, community-based curation, an important source of curated knowledge, requires support in role management, reviewing features and versioning. Here, we present Biological Knowledge Curation (BioKC), a web-based collaborative platform for the curation and annotation of biomedical knowledge following the standard data model from Systems Biology Markup Language (SBML). BioKC offers a graphical user interface for curation of complex molecular interactions and their annotation with stable identifiers and supporting sentences. With the support of collaborative curation and review, it allows to construct building blocks for systems biology diagrams and computational models. These building blocks can be published under stable identifiers and versioned and used as annotations, supporting knowledge building for modelling activities.


Asunto(s)
Programas Informáticos , Biología de Sistemas , Curaduría de Datos
6.
J Drugs Dermatol ; 23(3): e81-e82, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38443117

RESUMEN

Mastocytosis is a group of disorders characterized by the pathologic accumulation of mast cells in various tissues. One example of mastocytosis is urticaria pigmentosa, which presents with mastocytomas that can cause hives and, when irritated, pruritus. To our knowledge, we are describing the first case of urticaria pigmentosa without pruritus. The patient had a positive Darier's sign, stated that they never felt itchy, and denied ever using a topical steroid or antihistamine. Although our patient declined additional testing, patients like this may benefit from a detailed evaluation of their sensory system through both quantitative sensory testing and genetic analysis. J Drugs Dermatol. 2024;23(3):     doi:10.36849/JDD.7558e.


Asunto(s)
Urticaria Pigmentosa , Urticaria , Humanos , Urticaria Pigmentosa/diagnóstico , Prurito/diagnóstico , Prurito/etiología , Urticaria/diagnóstico , Mastocitos , Emociones
7.
World Neurosurg ; 185: 103-112, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38307200

RESUMEN

BACKGROUND: Flow diversion using the pipeline embolization device (PED) has been a paradigm shift for anterior circulation (AC) aneurysms. However, only a few studies report the long-term (≥1 year) angiographic and clinical outcomes for posterior circulation (PC) aneurysms. This study aims to compare the long-term safety and efficacy of treatment of AC and PC aneurysms with PED. METHODS: The databases included Ovid MEDLINE, Ovid EMBASE, Ovid Cochrane, and Scopus. Studies with at least 10 patients and 1-year follow-up were included. Twenty-four studies met our inclusion criteria. A random effect meta-analysis was performed to estimate the ischemic and hemorrhagic complications. A meta-analysis of proportions was performed to estimate the pooled rates of long-term complete aneurysmal occlusion, symptomatic stroke, aneurysmal rupture, and intracranial hemorrhage. RESULTS: There were 1952 aneurysms, of which 1547 (79.25%) were in the AC and 405 (20.75%) in the PC. The 1-year occlusion rate was 78% in AC compared to 73% in PC aneurysms (P < 0.01). The symptomatic infarct rate was 5% in AC compared to 13% in PC (P < 0.01). While the rupture rate was 1% in AC compared to 4% in PC (P = 0.01), the rate of intracranial hemorrhage was 2% for both (P = 0.99). CONCLUSIONS: The long-term occlusion rate after PED was higher in AC aneurysms, and the cumulative incidence of stroke and aneurysm rupture was higher in PC aneurysms.


Asunto(s)
Embolización Terapéutica , Aneurisma Intracraneal , Humanos , Embolización Terapéutica/métodos , Embolización Terapéutica/instrumentación , Embolización Terapéutica/efectos adversos , Aneurisma Intracraneal/terapia , Resultado del Tratamiento , Aneurisma Roto/terapia
8.
J Alzheimers Dis ; 97(2): 791-804, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38189752

RESUMEN

BACKGROUND: With continuously aging societies, an increase in the number of people with cognitive decline is to be expected. Aside from the development of causative treatments, the successful implementation of prevention strategies is of utmost importance to reduce the high societal burden caused by neurodegenerative diseases leading to dementia among which the most common cause is Alzheimer's disease. OBJECTIVE: The aim of the Luxembourgish "programme dementia prevention (pdp)" is to prevent or at least delay dementia in an at-risk population through personalized multi-domain lifestyle interventions. The current work aims to provide a detailed overview of the methodology and presents initial results regarding the cohort characteristics and the implementation process. METHODS: In the frame of the pdp, an extensive neuropsychological evaluation and risk factor assessment are conducted for each participant. Based on the results, individualized multi-domain lifestyle interventions are suggested. RESULTS: A total number of 450 participants (Mean age = 69.5 years; SD = 10.8) have been screened at different recruitment sites throughout the country, among whom 425 participants (94.4%) met the selection criteria. CONCLUSIONS: We provide evidence supporting the feasibility of implementing a nationwide dementia prevention program and achieving successful recruitment of the target population by establishing a network of different healthcare providers.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Luxemburgo/epidemiología , Disfunción Cognitiva/terapia , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/prevención & control , Estilo de Vida , Selección de Paciente
9.
World Neurosurg ; 181: e620-e627, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37898264

RESUMEN

INTRODUCTION: Skull-base chordomas are aggressive tumors with a propensity for recurrence/progression. Even with standard of care (SoC), 5-year recurrence rates are variable (19%-54%). This high recurrence/progression rate correlates with increased morbidity and mortality. We sought to analyze a multicenter cohort of skull base chordomas to identify predictors of progression in patients receiving SoC. METHODS: The [Blinded]-Neurosurgery data registry was queried for skull base chordomas treated from 2008-2020. Patients with the histopathologic diagnosis of chordoma were included. The cohort was composed of patients with preoperative and postoperative magnetic resonance imaging. Tumor volume and radiologic characteristics were obtained from axial T2 sequences using a Digital Imaging and Communications in Medicine viewer. Survival analysis was performed using Kaplan-Meier method, and time-to-event multivariate regression was performed to identify independent predictors of progression. RESULTS: The cohort included 195 patients, of which 66 patients met inclusion criteria; median age was 44, and 28 (42%) were females. Fifty-four (82%) received SoC, 7 (11%) resection only, and 5 (8%) radiotherapy only. Median preoperative and postoperative tumor volumes were 11.55 cm3 (0.33-54.89) and 0.34 cm3 (0-42.52), respectively. Recurrence rate with SoC was 37%. Postoperative tumor volume (P = 0.010) correlated with progression. A postoperative volume of >4.9 cm3 (P = 0.044), ≤81.3% of tumor resection (P = 0.02), and lower-clivus location (P < 0.005) correlated with decreased time to progression. CONCLUSIONS: Skull base chordomas can be challenging to resect. Even though maximal resection and radiotherapy improve rate of tumor progression, many of these lesions eventually recur. We have identified a postoperative tumor volume of ≥4.9 cm3 and extent of resection of ≤81.3% in this cohort as predictors of progression in patients receiving SoC.


Asunto(s)
Cordoma , Neoplasias de la Base del Cráneo , Femenino , Humanos , Masculino , Cordoma/diagnóstico por imagen , Cordoma/cirugía , Cordoma/patología , Estudios de Seguimiento , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Base del Cráneo/patología , Neoplasias de la Base del Cráneo/diagnóstico por imagen , Neoplasias de la Base del Cráneo/cirugía , Neoplasias de la Base del Cráneo/patología , Análisis de Supervivencia , Resultado del Tratamiento , Adulto
10.
J Neurosurg ; 140(2): 319-327, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37877961

RESUMEN

Oncolytic viral therapy is quickly emerging as a promising subset of immunotherapy, which theoretically can target tumor cells while sparing surrounding healthy cells by harnessing the replication machinery of viruses with tropism for tumor cells, resulting in direct oncolysis, and by transforming immunologically "cold" tumor into areas that elicit the host's immune response. This review provides an overview of oncolytic viral therapy until the present day, starting with the original concept in 1912. The general mechanism of oncolytic viruses (OVs) depends on selectively integrating them into tumor cells based on genetic engineering of viral genomic material, inducing oncolysis and eliciting the host's innate immune response. Moreover, a major component of oncolytic viral therapy has been herpes simplex virus, with talimogene laherparepvec being the only FDA-approved oncolytic viral therapy for the treatment of melanomas. This review explores the characteristics, advantages, disadvantages, and therapeutic uses of several DNA and RNA viral families. A snapshot of the oncolytic viral treatments used in the most recent and advanced clinical trials is also provided. Lastly, the challenges of implementing oncolytic viral therapy are explored, both at a molecular and clinical level, with a highlight of promising future directions. In particular, the lack of an optimal delivery method based on tumor type for oncolytic viral therapy poses a significant obstacle, even in clinical studies. Intrathecal continuous delivery of OVs is a promising prospect, potentially by adapting the novel continuous irrigation and drainage IRRAflow catheter. Further exploration and testing of the IRRAflow catheter should be undertaken.


Asunto(s)
Melanoma , Neoplasias , Viroterapia Oncolítica , Virus Oncolíticos , Humanos , Viroterapia Oncolítica/métodos , Melanoma/patología , Virus Oncolíticos/genética , Neoplasias/terapia , Inmunoterapia/métodos
11.
Acta Trop ; 249: 107048, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37931342

RESUMEN

Rickettsia species are obligate intracellular bacteria that can cause mild to severe human disease. Based on phylogeny, clinical symptoms, and antigenic properties, rickettsiae are classified into four groups. Infections by these agents are characterized by clinical symptoms ranging from self-limited to severe and even fatal febrile illnesses, depending on the Rickettsia spp. involved, the patient's predisposition, and timely medical care. The present study aimed to characterize rickettsial diseases in Yucatan according to clinical and laboratory features appearing in medical records corresponding to 427 samples taken between 2015 and 2018. A study was conducted over the period 2015-2018 on 427 samples. Clinical and laboratory features were documented from the patients' medical records. For molecular diagnosis, blood was collected in 3.8 % sodium citrate as anticoagulant, and DNA was extracted. Single-step and nested PCR amplification was performed using genus-specific primers for the rickettsial 17kDa and ompB genes. The amplicons obtained were purified and sequenced. A total of 22.7 % (97/427) positive cases of Rickettsia spp. were identified by PCR from 14.15 % (15/106) of the municipalities in Yucatan. 75.2 % (73/97) of the cases were from the city of Merida during the autumn (September-December). The age groups with the highest frequency of confirmed cases were pediatric (5-14 years) (57.7 %) and adults (25-49 years) (42.2 %). There were six fatal cases in children, one associated with R. typhi and five with R. rickettsii. In non-fatal cases, 32.9 % (32/97) corresponded to the spotted fever group (SFG), and 60.8 % (59/97) to the typhus group (TG). Significant differences in signs, and laboratory data, were observed between the pediatric and adult populations. For the treatment of patients, oral and intravenous doxycycline was used in severe hospitalized cases. Typhus group and spotted fever group Rickettsiae are endemic pathological agents found in urban and rural areas of our region. Molecular identification allows for greater diagnostic accuracy and timely treatment and consequently a better prognosis. It is necessary to implement or reinforce measures focused on the dissemination of knowledge regarding rickettsial diseases and their prevention.


Asunto(s)
Infecciones por Rickettsia , Rickettsia , Rickettsiosis Exantemáticas , Tifus Epidémico Transmitido por Piojos , Adulto , Humanos , Niño , Preescolar , Adolescente , México/epidemiología , Infecciones por Rickettsia/diagnóstico , Infecciones por Rickettsia/epidemiología , Infecciones por Rickettsia/microbiología , Rickettsiosis Exantemáticas/epidemiología
12.
J Chem Phys ; 159(22)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38063225

RESUMEN

The importance of nitrate and ammonium salts both in the environment and in biological processes cannot be questioned. In this work, using the TIP4P/2005 water model, aqueous solutions of nitrate and ammonium electrolytes are parametrized using scaled charges while keeping a rigid structure and nonpolarizable charge distributions. The models are optimized by systematically testing a set of properties for twelve electrolytes-eight nitrate and four ammonium salts-thus, enlarging the number of potential chemical species encompassed within the Madrid-2019 force field for ions. The capacity of the force field for predicting densities, ion-ion and ion-solvent structures, and transport properties of the solutions comprised by the trial batch of salts was tested and discussed. Both the dependence of the densities with the salt concentration and the solution structure were nicely reproduced by the models in the whole concentration range without any trace of precipitating events and with improved accuracy in comparison with recently reported models, while the agreement of the simulated transport properties with experimental data ranges from good to reasonable, depending on the ion/counterion pair. These scaled charge models might be considered as force fields embodying a reasonable compromise between exactness and general applicability and also as an important step in the development of accurate models for polyatomic ions.

13.
Mayo Clin Proc Innov Qual Outcomes ; 7(6): 534-543, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38035051

RESUMEN

Objective: To describe the safety and feasibility of a fast-track pathway for neurosurgical craniotomy patients receiving care in a neurosciences progressive care unit (NPCU). Patients and Methods: Traditionally, most craniotomy patients are admitted to the neurosciences intensive care unit (NSICU) for postoperative follow-up. Decreased availability of NSICU beds during the coronavirus disease-2019 delta surge led our team to establish a de-novo NPCU to preserve capacity for patients requiring high level of care and would bypass routine NSICU admissions. Patients were selected a priori by treating neurosurgeons on the basis of the potential need for high-level ICU services. After operation, selected patients were transferred to the postoperative care unit, where suitability for NPCU transfer was reassessed with checklist-criteria. This process was continued after the delta surge. Results: From July 1, 2021 to September 30, 2022, 57 patients followed the NPCU protocol. Thirty-four (59.6%) were women, and the mean age was 56 years. Fifty-seven craniotomies for 34 intra-axial and 23 extra-axial lesions were performed. After assessment and application of the checklist-criteria, 55 (96.5%) were transferred to NPCU, and only 2 (3.5%) were transferred to ICU. All 55 patients followed in NPCU had good safety outcomes without requiring NSICU transfer. This saved $143,000 and led to 55 additional ICU beds for emergent admissions. Conclusion: This fast-track craniotomy protocol provides early experience that a surgeon-selected group of patients may be suitably monitored outside the traditional NSICU. This system has the potential to reduce overall health care expenses, increase capacity for NSICU bed availability, and change the paradigm of NSICU admission.

14.
Neurosurg Rev ; 46(1): 284, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37882896

RESUMEN

Flow diversion with the pipeline embolization device (PED) is increasingly used to treat intracranial aneurysms with high obliteration rates and low morbidity. However, long-term (≥ 1 year) angiographic and clinical outcomes still require further investigation. The aim of this study was to compare the occlusion and complication rates for small (< 10 mm) versus large (10-25 mm) aneurysms at long-term following treatment with PED. A systematic review and meta-analysis were performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We conducted a comprehensive search of English language databases including Ovid MEDLINE and Epub Ahead of Print, In-Process, and Daily, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. Our studies included a minimum of 10 patients treated with PED for small vs. large aneurysms and with at least 12 months of follow-up. The primary safety endpoint was the rate of clinical complications measured by the occurrence of symptomatic stroke (confirmed clinically and radiographically), intracranial hemorrhage, or aneurysmal rupture. The primary efficacy endpoint was the complete aneurysm occlusion rate. Our analysis included 19 studies with 1277 patients and 1493 aneurysms. Of those, 1378 aneurysms met our inclusion criteria. The mean age was 53.9 years, and most aneurysms were small (89.75%; N = 1340) in women (79.1%; N = 1010). The long-term occlusion rate was 73% (95%, CI 65 to 80%) in small compared to 84% (95%, CI 76 to 90%) in large aneurysms (p < 0.01). The symptomatic thromboembolic complication rate was 5% (95%, CI 3 to 9%) in small compared to 7% (95%, CI 4 to 13%) in large aneurysms (p = 0.01). The rupture rate was 2% vs. 4% (p = 0.92), and the rate of intracranial hemorrhage was 2% vs. 4% (p = 0.96) for small vs. large aneurysms, respectively; however, these differences were not statistically significant. The long-term occlusion rate after PED treatment is higher in large vs. small aneurysms. Symptomatic thromboembolic rates with stroke are also higher in large vs. small aneurysms. The difference in the rates of aneurysm rupture and intracranial hemorrhage was insignificant. Although the PED seems a safe and effective treatment for small and large aneurysms, further studies are required to clarify how occlusion rate and morbidity are affected by aneurysm size.


Asunto(s)
Aneurisma Roto , Aneurisma Intracraneal , Accidente Cerebrovascular , Humanos , Femenino , Persona de Mediana Edad , Aneurisma Roto/cirugía , Aneurisma Intracraneal/cirugía , Hemorragias Intracraneales , Angiografía
15.
Rev. Fac. Med. UNAM ; 66(5): 7-23, sep.-oct. 2023. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1535213

RESUMEN

Resumen La preeclampsia es una patología con alta morbimortalidad a nivel mundial. En esta enfermedad la placenta es un órgano de choque donde la inflamación y la respuesta inmunológica generan el daño que se traduce en el cuadro clínico característico. La tríada clásica en preeclampsia está integrada por hipertensión, edema y proteinuria, por lo que se piensa que el endotelio debe estar afectado por la actividad inflamatoria-inmunológica. El sistema inmunológico actúa en el desarrollo del embarazo y lo hace a diferentes tiempos y regulando de manera fisiológica. Tanto componentes celulares como humorales de la respuesta innata y adquirida han sido estudiados en pacientes con preeclampsia y se ha determinado que su participación es decisiva en la fisiopatología de esta enfermedad. La participación del sistema inmunológico en la fisiopatología de la preeclampsia alcanza un alto nivel de complejidad pues interacciona con otros sistemas (coagulación, renal, cardiovascular y endocrinológico entre otros) favoreciendo así la enfermedad. Es por esto que el tratamiento debe ser integral, con una visión holística del padecimiento y que requiere de un equipo multidisciplinario, que actué armónicamente para así alcanzar el mayor éxito terapéutico con la menor frecuencia de secuelas para el binomio madre-feto o madre-recién nacido. En la gestación se desarrolla la denominada "tolerancia inmunológica del embarazo", en ese estado de tolerancia inmunológica las células B y T pueden reconocer antígenos específicos (por ejemplo, los paternos) y posteriormente activarse y generar la respuesta inmunológica, por lo que la preeclampsia podría ser considerada como una patología autoinmune, donde la perdida de la tolerancia inmunológica sería la piedra angular en la fisiopatología, conocer como limitar o regular esta activación celular anómala podría servir para proponer nuevos acercamientos terapéuticos y controlar así esta enfermedad.


Abstract Preeclampsia is a pathology with high morbidity and mortality worldwide. In this disease, the placenta is an organ of shock where inflammation and the immune response generate the damage that results in the characteristic clinical scenario. The classic triad in preeclampsia is made up of hypertension, edema, and proteinuria, so it is thought that the endothelium must be affected by inflammatory-immunological activity. The immune system acts in the development of pregnancy and does so at different times and regulating physiologically. Both, cellular and humoral components of the innate and acquired response have been studied in patients with preeclampsia and it has been determined that their participation is decisive in the pathophysiology of this disease. The involvement of the immune system in the pathophysiology of preeclampsia reaches a high level of complexity since it interacts with other systems (coagulation, renal, cardiovascular and endocrinological among others) thus favoring the disease. For this reason, treatment must be comprehensive, with a holistic vision of the condition and requires a multidisciplinary team that acts harmoniously to achieve the greatest therapeutic success with the least frequency of sequelae for the mother-fetus or mother-newborn dyads. During pregnancy, the so-called "immunological tolerance of pregnancy" develops, in this state of immunological tolerance the B and T cells can recognize specific antigens (for example, the paternal ones) and later activate and generate the immune response, which is why preeclampsia could being considered an autoimmune pathology, where the loss of immunological tolerance would be the cornerstone of pathophysiology, knowing how to limit or regulate this abnormal cell activation could help to propose new therapeutic approaches and thus control this disease.

16.
J Neurosurg Spine ; 39(5): 652-660, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37728388

RESUMEN

OBJECTIVE: Chordomas are slow-growing tumors derived from notochord remnants. Despite margin-negative excision and postoperative radiation therapy, spinal chordomas (SCs) often progress. The potential of immunohistochemical (IHC) markers, such as epithelial membrane antigen (EMA), combined with machine learning algorithms to predict long-term (≥ 12 months) postoperative tumor progression, has been understudied. The authors aimed to identify IHC markers using trained tree-based algorithms to predict long-term (≥ 12 months) postoperative tumor progression. METHODS: The authors reviewed the records of patients who underwent resection of SCs between January 2017 and June 2021 across the Mayo Clinic enterprise. Demographics, type of treatment, histopathology, and other relevant clinical factors were abstracted from each patient's record. Low tumor progression was defined as more than a 94.3-mm3 decrease in the tumor size at the latest radiographic follow-up. Decision trees and random forest classifiers were trained and tested to predict the long-term volumetric progression after an 80/20 data split. RESULTS: Sixty-two patients diagnosed with and surgically treated for SC were identified, of whom 31 were found to have a more advanced tumor progression based on the tumor volume change cutoff of 94.3 mm3. The mean age was 54.3 ± 13.8 years, and most patients were male (62.9%) and White (98.4%). The most common treatment modality was subtotal resection with radiation therapy (35.5%), with proton beam therapy being the most common (71%). Most SCs were sacrococcygeal (41.9%), followed by cervical (32.3%). EMA-positive SCs had a postoperative progression risk of 67%. Pancytokeratin-positive SCs had a progression rate of 67%; however, patients with S100 protein-positive SCs had a 54% risk of progression. The accuracy of this model in predicting the progression of unseen test data was 66%. Pancytokeratin (mean minimal depth = 1.57), EMA (mean minimal depth = 1.58), cytokeratin A1/A3 (mean minimal depth = 1.59), and S100 protein (mean minimal depth = 1.6) predicted the long-term volumetric progression. Multiway variable importance plots show the relative importance of the top 10 variables based on three measures of varying significance and their predictive role. CONCLUSIONS: These IHC variables with tree-based machine learning tools successfully demonstrate a high capacity to identify a patient's tumor progression pattern with an accuracy of 66%. Pancytokeratin, EMA, cytokeratin A1/A3, and S100 protein were the IHC drivers of a low tumor progression. This shows the power of machine learning algorithms in analyzing and predicting outcomes of rare conditions in a small sample size.


Asunto(s)
Cordoma , Neoplasias de la Columna Vertebral , Humanos , Adulto , Persona de Mediana Edad , Anciano , Cordoma/cirugía , Cordoma/patología , Proteínas S100 , Recurrencia Local de Neoplasia/patología , Queratinas/metabolismo , Neoplasias de la Columna Vertebral/diagnóstico
17.
Science ; 381(6654): 216-221, 2023 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-37440632

RESUMEN

The domestication of forest trees for a more sustainable fiber bioeconomy has long been hindered by the complexity and plasticity of lignin, a biopolymer in wood that is recalcitrant to chemical and enzymatic degradation. Here, we show that multiplex CRISPR editing enables precise woody feedstock design for combinatorial improvement of lignin composition and wood properties. By assessing every possible combination of 69,123 multigenic editing strategies for 21 lignin biosynthesis genes, we deduced seven different genome editing strategies targeting the concurrent alteration of up to six genes and produced 174 edited poplar variants. CRISPR editing increased the wood carbohydrate-to-lignin ratio up to 228% that of wild type, leading to more-efficient fiber pulping. The edited wood alleviates a major fiber-production bottleneck regardless of changes in tree growth rate and could bring unprecedented operational efficiencies, bioeconomic opportunities, and environmental benefits.


Asunto(s)
Edición Génica , Lignina , Populus , Madera , Carbohidratos/análisis , Lignina/genética , Madera/genética , Sistemas CRISPR-Cas , Populus/genética , Papel , Crecimiento Sostenible
18.
J Chem Theory Comput ; 19(16): 5380-5393, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37506381

RESUMEN

In this work, we computed electrical conductivities under ambient conditions of aqueous NaCl and KCl solutions by using the Einstein-Helfand equation. Common force fields (charge q = ±1 e) do not reproduce the experimental values of electrical conductivities, viscosities, and diffusion coefficients. Recently, we proposed the idea of using different charges to describe the potential energy surface (PES) and the dipole moment surface (DMS). In this work, we implement this concept. The equilibrium trajectories required to evaluate electrical conductivities (within linear response theory) were obtained by using scaled charges (with the value q = ±0.75 e) to describe the PES. The potential parameters were those of the Madrid-Transport force field, which accurately describe viscosities and diffusion coefficients of these ionic solutions. However, integer charges were used to compute the conductivities (thus describing the DMS). The basic idea is that although the scaled charge describes the ion-water interaction better, the integer charge reflects the value of the charge that is transported due to the electric field. The agreement obtained with experiments is excellent, as for the first time electrical conductivities (and the other transport properties) of NaCl and KCl electrolyte solutions are described with high accuracy for the whole concentration range up to their solubility limit. Finally, we propose an easy way to obtain a rough estimate of the actual electrical conductivity of the potential model under consideration using the approximate Nernst-Einstein equation, which neglects correlations between different ions.

19.
Am Surg ; 89(12): 5881-5890, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37220891

RESUMEN

INTRODUCTION: Pulmonary complications after liver transplantation (LT) have previously been associated with longer hospital stays and ventilator time, and higher mortality. This study reports the outcomes for a specific pulmonary complication, pleural effusion, in LT recipients. METHODS: Records from a single transplant center were analyzed retrospectively for all adult LT patients. Patients with documented pleural effusion by radiographic imaging within 30 days pre- or post-transplant were considered as cases. Outcomes included length of hospital stay, discharge disposition, hospital readmission, discharge with home oxygen, and 1-year survival. RESULTS: During the 4-year study period, 512 LTs were performed, with 107 patients (21%) developing a peri-transplant pleural effusion. In total, 49 patients (10%) had a pre-transplant effusion, 91 (18%) had a post-transplant effusion, and 32 (6%) had both. Characteristics associated with the presence of any pleural effusion included an increasing model for end-stage liver disease score, re-transplantation, diagnosis of alcoholic liver disease, low protein levels, and sarcopenia. Effusion patients had longer hospital stays (17 vs 9 days, P < .001) and higher likelihood of discharge to a care facility (48% vs 21%, P < .001). Ninety-day readmission occurred in 69% of effusion patients (vs 44%, P < .001). One-year patient survival with any effusion was 86% (vs 94%, P < .01). CONCLUSIONS: Overall, 21% of recipients developed a clinically significant peri-transplant pleural effusion. Pleural effusion was associated with worse outcomes for all clinical measures. Risk factors for the development of pleural effusion included higher MELD score (>20), re-transplantation, alcoholic liver disease, and poor nutrition status, including poor muscle mass.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Hepatopatías Alcohólicas , Trasplante de Hígado , Desnutrición , Derrame Pleural , Adulto , Humanos , Trasplante de Hígado/efectos adversos , Enfermedad Hepática en Estado Terminal/complicaciones , Enfermedad Hepática en Estado Terminal/cirugía , Enfermedad Hepática en Estado Terminal/diagnóstico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Derrame Pleural/etiología , Desnutrición/complicaciones
20.
J Chem Phys ; 158(18)2023 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-37158326

RESUMEN

In this paper, the solubility of carbon dioxide (CO2) in water along the isobar of 400 bar is determined by computer simulations using the well-known TIP4P/Ice force field for water and the TraPPE model for CO2. In particular, the solubility of CO2 in water when in contact with the CO2 liquid phase and the solubility of CO2 in water when in contact with the hydrate have been determined. The solubility of CO2 in a liquid-liquid system decreases as the temperature increases. The solubility of CO2 in a hydrate-liquid system increases with temperature. The two curves intersect at a certain temperature that determines the dissociation temperature of the hydrate at 400 bar (T3). We compare the predictions with T3 obtained using the direct coexistence technique in a previous work. The results of both methods agree, and we suggest 290(2) K as the value of T3 for this system using the same cutoff distance for dispersive interactions. We also propose a novel and alternative route to evaluate the change in chemical potential for the formation of hydrates along the isobar. The new approach is based on the use of the solubility curve of CO2 when the aqueous solution is in contact with the hydrate phase. It considers rigorously the non-ideality of the aqueous solution of CO2, providing reliable values for the driving force for nucleation of hydrates in good agreement with other thermodynamic routes used. It is shown that the driving force for hydrate nucleation at 400 bar is larger for the methane hydrate than for the carbon dioxide hydrate when compared at the same supercooling. We have also analyzed and discussed the effect of the cutoff distance of dispersive interactions and the occupancy of CO2 on the driving force for nucleation of the hydrate.

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