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1.
Curr Cardiol Rep ; 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39276266

RESUMEN

PURPOSE OF REVIEW: To discuss the evolution in the approach to pericardial effusions and drainage from a historical perspective, the present state, and pathways for future innovative therapies. RECENT FINDINGS: Incorporation of advanced imaging tools has dramatically improved the safety profile of pericardial interventions. Outcome data allow for refined approaches to management of pericardial disease in special populations, such as pulmonary arterial hypertension. Consideration of intrapericardial interventions and pharmacotherapy represent novel and promising approaches to management of pericardial effusions moving forward. Although the impact of excess or rapidly accumulating pericardial fluid on hemodynamics has been recognized for centuries, the therapeutic approaches have only recently become more refined with the routine incorporation of such tools as echocardiography and fluoroscopy. The most utilized approaches for pericardiocentesis include the apical, subxiphoid, and parasternal, and the most favorable approach is that in which the pericardial fluid is closest to the body surface, where intervening vital structures are least likely to be damaged. With the notable exception of patients with pre-existing pulmonary hypertension, complete decompression of pericardial fluid with careful drain management reduces likelihood of pericardial effusion recurrence. In addition, percutaneous balloon pericardiotomies have been demonstrated to reduce recurrence in nonmalignant effusions.

2.
ACS Appl Mater Interfaces ; 16(27): 35447-35462, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38940537

RESUMEN

Membranous nephropathy (MN) is a common immune-mediated glomerular disease that requires the development of safe and highly effective therapies. Celastrol (CLT) has shown promise as a therapeutic molecule candidate, but its clinical use is currently limited due to off-target toxicity. Given that excess levels of reactive oxygen species (ROS) contributing to podocyte damage is a key driver of MN progression to end-stage renal disease, we rationally designed ROS-responsive cationic polymeric nanoparticles (PPS-CPNs) with a well-defined particle size and surface charge by employing poly(propylene sulfide)-polyethylene glycol (PPS-PEG) and poly(propylene sulfide)-polyethylenimine (PPS-PEI) to selectively deliver CLT to the damaged glomerulus for MN therapy. Experimental results show that PPS-CPNs successfully crossed the fenestrated endothelium, accumulated in the glomerular basement membrane (GBM), and were internalized by podocytes where rapid drug release was triggered by the overproduction of ROS, thereby outperforming nonresponsive CLT nanotherapy to alleviate subepithelial immune deposits, podocyte foot process effacement, and GBM expansion in a rat MN model. Moreover, the ROS-responsive CLT nanotherapy was associated with significantly lower toxicity to major organs than free CLT. These results suggest that encapsulating CLT into PPS-CPNs can improve efficacy and reduce toxicity as a promising treatment option for MN.


Asunto(s)
Glomerulonefritis Membranosa , Nanopartículas , Triterpenos Pentacíclicos , Podocitos , Especies Reactivas de Oxígeno , Animales , Especies Reactivas de Oxígeno/metabolismo , Nanopartículas/química , Glomerulonefritis Membranosa/tratamiento farmacológico , Glomerulonefritis Membranosa/patología , Ratas , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/farmacología , Podocitos/efectos de los fármacos , Podocitos/metabolismo , Polietilenglicoles/química , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/patología , Glomérulos Renales/metabolismo , Ratas Sprague-Dawley , Humanos , Masculino , Polímeros/química , Polímeros/farmacología , Sulfuros/química , Sulfuros/farmacología , Sulfuros/uso terapéutico , Polietileneimina/química , Portadores de Fármacos/química
3.
Proc Natl Acad Sci U S A ; 121(17): e2321989121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38625941

RESUMEN

Type IVa pili (T4aP) are ubiquitous cell surface filaments important for surface motility, adhesion to surfaces, DNA uptake, biofilm formation, and virulence. T4aP are built from thousands of copies of the major pilin subunit and tipped by a complex composed of minor pilins and in some systems also the PilY1 adhesin. While major pilins of structurally characterized T4aP have lengths of <165 residues, the major pilin PilA of Myxococcus xanthus is unusually large with 208 residues. All major pilins have a conserved N-terminal domain and a variable C-terminal domain, and the additional residues of PilA are due to a larger C-terminal domain. We solved the structure of the M. xanthus T4aP (T4aPMx) at a resolution of 3.0 Å using cryo-EM. The T4aPMx follows the structural blueprint of other T4aP with the pilus core comprised of the interacting N-terminal α1-helices, while the globular domains decorate the T4aP surface. The atomic model of PilA built into this map shows that the large C-terminal domain has more extensive intersubunit contacts than major pilins in other T4aP. As expected from these greater contacts, the bending and axial stiffness of the T4aPMx is significantly higher than that of other T4aP and supports T4aP-dependent motility on surfaces of different stiffnesses. Notably, T4aPMx variants with interrupted intersubunit interfaces had decreased bending stiffness, pilus length, and strongly reduced motility. These observations support an evolutionary scenario whereby the large major pilin enables the formation of a rigid T4aP that expands the environmental conditions in which the T4aP system functions.


Asunto(s)
Proteínas Fimbrias , Myxococcus xanthus , Proteínas Fimbrias/metabolismo , Myxococcus xanthus/genética , Myxococcus xanthus/metabolismo , Fimbrias Bacterianas/metabolismo , Estructura Secundaria de Proteína , Virulencia
4.
Open Heart ; 11(1)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38663889

RESUMEN

OBJECTIVES: We sought to determine the relationship between the degree of left ventricular ejection fraction (LVEF) impairment and the frequency and type of bleeding events after percutaneous coronary intervention (PCI). DESIGN: This was an observational retrospective cohort analysis. Patients who underwent PCI from 2009 to 2017 were identified from our institutional National Cardiovascular Disease Registry (NCDR) CathPCI database. Patients were stratified by pre-PCI LVEF: preserved (≥50%), mildly reduced (41%-49%) and reduced (≤40%) LVEF. PRIMARY OUTCOME MEASURES: The outcome was major bleeding, defined by NCDR criteria. Events were classified based on bleeding aetiology and analysed by multivariable logistic regression. RESULTS: Among 13 537 PCIs, there were 817 bleeding events (6%). The rate of bleeding due to any cause, blood transfusion, gastrointestinal bleeding and coronary artery perforation or tamponade each increased in a stepwise fashion comparing preserved, mildly reduced and reduced LVEF reduction (p<0.05 for all comparisons). However, there were no differences in bleeding due to asymptomatic drops in haemoglobin, access site haematoma or retroperitoneal bleeding. After multivariable adjustment, mildly reduced and reduced LVEF remained independent predictors of bleeding events (OR 1.36, 95% CI 1.06 to 1.74, p<0.05 and OR 1.73, 95% CI 1.45 to 2.06, p<0.0001). CONCLUSIONS: The degree of LV dysfunction is an independent predictor of post-PCI major bleeding events. Patients with mildly reduced or reduced LVEF are at greatest risk of post-PCI bleeding, driven by an increased need for blood transfusion, major GI bleeding events and coronary artery perforation or tamponade. Pre-PCI LV dysfunction does not predict asymptomatic declines in haemoglobin, access site haematoma or retroperitoneal bleeding.


Asunto(s)
Insuficiencia Cardíaca , Intervención Coronaria Percutánea , Sistema de Registros , Volumen Sistólico , Función Ventricular Izquierda , Humanos , Intervención Coronaria Percutánea/efectos adversos , Masculino , Femenino , Estudios Retrospectivos , Volumen Sistólico/fisiología , Anciano , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Función Ventricular Izquierda/fisiología , Factores de Riesgo , Persona de Mediana Edad , Medición de Riesgo/métodos , Incidencia , Estados Unidos/epidemiología , Resultado del Tratamiento , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/cirugía , Enfermedad de la Arteria Coronaria/terapia , Estudios de Seguimiento , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/diagnóstico , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/epidemiología , Hemorragia Posoperatoria/diagnóstico , Factores de Tiempo
5.
Nat Chem ; 16(5): 800-808, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38316987

RESUMEN

Cryo-electron microscopy has delivered a resolution revolution for biological self-assemblies, yet only a handful of structures have been solved for synthetic supramolecular materials. Particularly for chromophore supramolecular aggregates, high-resolution structures are necessary for understanding and modulating the long-range excitonic coupling. Here, we present a 3.3 Å structure of prototypical biomimetic light-harvesting nanotubes derived from an amphiphilic cyanine dye (C8S3-Cl). Helical 3D reconstruction directly visualizes the chromophore packing that controls the excitonic properties. Our structure clearly shows a brick layer arrangement, revising the previously hypothesized herringbone arrangement. Furthermore, we identify a new non-biological supramolecular motif-interlocking sulfonates-that may be responsible for the slip-stacked packing and J-aggregate nature of the light-harvesting nanotubes. This work shows how independently obtained native-state structures complement photophysical measurements and will enable accurate understanding of (excitonic) structure-function properties, informing materials design for light-harvesting chromophore aggregates.

6.
bioRxiv ; 2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37503255

RESUMEN

Type IV pili (T4P) are ubiquitous bacterial cell surface filaments important for surface motility, adhesion to biotic and abiotic surfaces, DNA uptake, biofilm formation, and virulence. T4P are built from thousands of copies of the major pilin subunit and tipped by a complex composed of minor pilins and in some systems also the PilY1 adhesin. While the major pilins of structurally characterized T4P have lengths of up to 161 residues, the major pilin PilA of Myxococcus xanthus is unusually large with 208 residues. All major pilins have a highly conserved N-terminal domain and a highly variable C-terminal domain, and the additional residues in the M. xanthus PilA are due to a larger C-terminal domain. We solved the structure of the M. xanthus T4P (T4P Mx ) at a resolution of 3.0 Å using cryo-electron microscopy (cryo-EM). The T4P Mx follows the structural blueprint observed in other T4P with the pilus core comprised of the extensively interacting N-terminal α1-helices while the globular domains decorate the T4P surface. The atomic model of PilA built into this map shows that the large C-terminal domain has much more extensive intersubunit contacts than major pilins in other T4P. As expected from these greater contacts, the bending and axial stiffness of the T4P Mx is significantly higher than that of other T4P and supports T4P-dependent motility on surfaces of different stiffnesses. Notably, T4P Mx variants with interrupted intersubunit interfaces had decreased bending stiffness and strongly reduced motility on all surfaces. These observations support an evolutionary scenario whereby the large major pilin enables the formation of a rigid T4P that expands the environmental conditions in which the T4P system functions.

8.
J Soc Cardiovasc Angiogr Interv ; 2(1): 100536, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-39132520

RESUMEN

Out-of-hospital cardiac arrest (OHCA) is among the most common causes of death in the United States. Early coronary angiography (CAG) and percutaneous coronary intervention (PCI) have been associated with improved long-term outcomes in patients with ST-segment elevation (STE) on prearrest or postarrest electrocardiograms. However, data on the utility of catheterization and PCI for improving outcomes after OHCA in patients without STE on electrocardiograms are heterogeneous, with variable results. Although older data have suggested that there is a benefit, recent randomized controlled trials have demonstrated that performing early CAG in patients with OHCA without STE on electrocardiograms may not improve outcomes. In recognition that neurologic devastation and multiorgan failure are common in these patients, physicians face the challenge of selecting appropriate patients for cardiac catheterization and PCI. This review aims to summarize the current data on this topic, with the goal to guide decision making regarding the timing and appropriateness of CAG in patients with OHCA without STE on electrocardiograms, utilizing an evidence-based approach to streamline the patient selection process.

9.
Phys Med Biol ; 68(1)2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36546347

RESUMEN

Objective. Proton dosimetric uncertainties resulting from the patient's daily setup errors in rotational directions exist even with advanced image-guided radiotherapy techniques. Thus, we developed a new rotational robust optimization SPArc algorithm (SPArcrot) to mitigate the dosimetric impact of the rotational setup error in Raystation ver. 6.02 (RaySearch Laboratory AB, Stockholm, Sweden).Approach.The initial planning CT was rotated ±5° simulating the worst-case setup error in the roll direction. The SPArcrotuses a multi-CT robust optimization framework by taking into account of such rotational setup errors. Five cases representing different disease sites were evaluated. Both SPArcoriginaland SPArcrotplans were generated using the same translational robust optimized parameters. To quantitatively investigate the mitigation effect from the rotational setup errors, all plans were recalculated using a series of pseudo-CT with rotational setup error (±1°/±2°/±3°/±5°). Dosimetric metrics such as D98% of CTV, and 3D gamma analysis were used to assess the dose distribution changes in the target and OARs.Main results.The magnitudes of dosimetric changes in the targets due to rotational setup error were significantly reduced by the SPArcrotcompared to SPArc in all cases. The uncertainties of the max dose to the OARs, such as brainstem, spinal cord and esophagus were significantly reduced using SPArcrot. The uncertainties of the mean dose to the OARs such as liver and oral cavity, parotid were comparable between the two planning techniques. The gamma passing rate (3%/3 mm) was significantly improved for CTV of all tumor sites through SPArcrot.Significance.Rotational setup error is one of the major issues which could lead to significant dose perturbations. SPArcrotplanning approach can consider such rotational error from patient setup or gantry rotation error by effectively mitigating the dose uncertainties to the target and in the adjunct series OARs.


Asunto(s)
Terapia de Protones , Radioterapia de Intensidad Modulada , Humanos , Órganos en Riesgo , Protones , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Errores de Configuración en Radioterapia , Radioterapia de Intensidad Modulada/métodos , Terapia de Protones/métodos , Osteonectina
10.
Cell ; 185(19): 3487-3500.e14, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36057255

RESUMEN

The supercoiling of bacterial and archaeal flagellar filaments is required for motility. Archaeal flagellar filaments have no homology to their bacterial counterparts and are instead homologs of bacterial type IV pili. How these prokaryotic flagellar filaments, each composed of thousands of copies of identical subunits, can form stable supercoils under torsional stress is a fascinating puzzle for which structural insights have been elusive. Advances in cryoelectron microscopy (cryo-EM) make it now possible to directly visualize the basis for supercoiling, and here, we show the atomic structures of supercoiled bacterial and archaeal flagellar filaments. For the bacterial flagellar filament, we identify 11 distinct protofilament conformations with three broad classes of inter-protomer interface. For the archaeal flagellar filament, 10 protofilaments form a supercoil geometry supported by 10 distinct conformations, with one inter-protomer discontinuity creating a seam inside of the curve. Our results suggest that convergent evolution has yielded stable superhelical geometries that enable microbial locomotion.


Asunto(s)
Flagelos , Flagelina , Archaea , Bacterias , Microscopía por Crioelectrón , Fimbrias Bacterianas/química , Subunidades de Proteína/análisis
11.
Allergy Asthma Clin Immunol ; 18(1): 66, 2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35927714

RESUMEN

BACKGROUND: Several miRNAs are now known to have clear connections to the pathogenesis of asthma. The present study focused on the potential role of miR-3934 during asthma development. METHODS: miR-3934 was detected as a down-regulated miRNA in basophils by sequencing analysis. Next, the expression levels of miR-3934 in peripheral blood mononuclear cells of 50 asthma patients and 50 healthy volunteers were examined by RT-qPCR methods. The basophils were then treated with AGEs and transfected with miR-3934 mimics. The apoptosis levels were examined by flow cytometry assay; and the expression levels of cytokines were detected using the ELISA kits. Finally, the Western blot was performed to examined the expression of key molecules in the TGF-ß/Smad signaling pathway. RESULTS: miR-3934 was down-regulated in the basophils of asthmatic patients. The expression of the pro-inflammatory cytokines IL-6, IL-8 and IL-33 was enhanced in basophils from asthmatic patients, and this effect was partially reversed by transfection of miR-3934 mimics. Furthermore, receiver operating characteristics analysis showed that miR-3934 levels can be used to distinguish asthma patients from healthy individuals. miR-3934 partially inhibited advanced glycation end products-induced increases in basophil apoptosis by suppressing expression of RAGE. CONCLUSION: Our results indicate that miR-3934 acts to mitigate the pathogenesis of asthma by targeting RAGE and suppressing TGF-ß/Smad signaling.

12.
Magn Reson Imaging ; 93: 135-144, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35973572

RESUMEN

PURPOSE: To find magnetic resonance imaging (MRI) precursors of spontaneous intracerebral hemorrhage in stroke-prone spontaneously hypertensive rats (SHRSP). METHOD: SHRSP rats were used with both a low/high salt (n = 18 or 11) Japanese diet and salty drinking water to generate spontaneous intracerebral hemorrhage (ICH). Various MRI sequences, and in particular, susceptibility weighted imaging (SWI), were used and combined with a gadolinium (Gd) contrast agent or oxygen gas to identify the rupture of the blood brain barrier (BBB) and the temporal ICH. RESULTS: Most rats developed hypertensive ICH stroke in the high salt group during the 10-13 week period compared to only one third of rats in the low salt group during the 14-18 week period. The location of stroke for both the low/high-salt groups was highest in the striatum (58%/43%), followed by the cortex (21%/30%). The edematous enhancement on T2 weighted (T2W) imaging or Gd based T1 weighted (Gd-T1W) imaging due to the ruptured BBB preceded the striatal hemorrhages seen on SWI. The most recent bleeds were observed on temporal SWI or on oxygen-enhanced SWI. The mode of the volume of bleeds was 0.4 mm3. A positive correlation between susceptibility x volume and R2* x volume of the bleeds was observed. CONCLUSIONS: SHRSP rats with the high salt diet effectively generated a hypertensive hemorrhagic stroke which could be monitored by various MRI sequences. The venous dilation on SWI may precede any abnormality on T2W or Gd-T1W imaging. The edematous enhancement on T2W or Gd-T1W indicated a BBB breakdown that may precede striatal ICH by several days. This suggests the need for immediate treatment to improve outcome if this finding is observed. The use of oxygen with SWI was able to help differentiate old bleeds from very recent bleeds.


Asunto(s)
Hipertensión , Accidente Cerebrovascular , Animales , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/diagnóstico por imagen , Gadolinio , Hipertensión/complicaciones , Hipertensión/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Oxígeno , Ratas , Ratas Endogámicas SHR , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/patología
13.
Int J Gen Med ; 15: 6549-6560, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35974801

RESUMEN

Purpose: This study aims to establish a risk prediction model for muscular calf vein thrombosis (MCVT) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods: The research sample consisted of 248 patients with AECOPD and all of them underwent vascular ultrasounds of both lower limbs in this retrospective study. Univariate analysis and multivariate logistic regression analysis were conducted on factors with significant group differences to screen for the independent risk factors of MCVT. A nomogram to predict the risk of MCVT was constructed and validated with bootstrap resampling. Results: According to the exclusion criteria, 240 patients were included for analysis, divided into the MCVT group (n = 81) and the non-MCVT group (n = 159). Multivariate logistic regression analyses showed that hypertension, elevated MPV, reduced albumin (ALB), elevated D-dimer and bed rest ≥3 days were independent risk factors for MCVT in AECOPD. A nomogram model for predicting AECOPD with MCVT was established based on them. The area under the curve (AUC) of receiver operating characteristic (ROC) curve for the prediction model and the simplified Wells score was 0.784 (95% CI: 0.722-0.847) and 0.659 (95% CI: 0.583-0.735), respectively. The cut-off value and Youden index of prediction model were 0.248 and 0.454, respectively. At the same time, the sensitivity, specificity, positive predictive value, and negative predictive value of the prediction model were 85.9%, 59.5%, 84.6%, and 77.4%, respectively. The sensitivity and specificity of the simplified Wells score were 67.9% and 56.3%, respectively. Validation by the use of bootstrap resampling revealed optimal discrimination and calibration, and the decision analysis curve (DAC) suggested that this prediction model involved high clinical practicability. Conclusion: We developed a nomogram that can predict the risk of MCVT for AECOPD patients. This model has the potential to assist clinicians in making treatment recommendations and formulating corresponding prevention measures.

14.
Int J Mol Sci ; 23(13)2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35806028

RESUMEN

Due to its essential role in cellular processes, actin is a common target for bacterial toxins. One such toxin, TccC3, is an effector domain of the ABC-toxin produced by entomopathogenic bacteria of Photorhabdus spp. Unlike other actin-targeting toxins, TccC3 uniquely ADP-ribosylates actin at Thr-148, resulting in the formation of actin aggregates and inhibition of phagocytosis. It has been shown that the fully modified F-actin is resistant to depolymerization by cofilin and gelsolin, but their effects on partially modified actin were not explored. We found that only F-actin unprotected by tropomyosin is the physiological TccC3 substrate. Yet, ADP-ribosylated G-actin can be produced upon cofilin-accelerated F-actin depolymerization, which was only mildly inhibited in partially modified actin. The affinity of TccC3-ADP-ribosylated G-actin for profilin and thymosin-ß4 was weakened moderately but sufficiently to potentiate spontaneous polymerization in their presence. Interestingly, the Arp2/3-mediated nucleation was also potentiated by T148-ADP-ribosylation. Notably, even partially modified actin showed reduced bundling by plastins and α-actinin. In agreement with the role of these and other tandem calponin-homology domain actin organizers in the assembly of the cortical actin network, TccC3 induced intense membrane blebbing in cultured cells. Overall, our data suggest that TccC3 imposes a complex action on the cytoskeleton by affecting F-actin nucleation, recycling, and interaction with actin-binding proteins involved in the integration of actin filaments with each other and cellular elements.


Asunto(s)
Photorhabdus , ADP Ribosa Transferasas/química , Citoesqueleto de Actina/metabolismo , Factores Despolimerizantes de la Actina/metabolismo , Actinas/metabolismo , Adenosina Difosfato/metabolismo
15.
Front Oncol ; 12: 804036, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35664795

RESUMEN

Purpose: To explore the role of using Pencil Beam Scanning (PBS) proton beam therapy in single lesion brain stereotactic radiosurgery (SRS), we developed and validated a dosimetric in silico model to assist in the selection of an optimal treatment approach among the conventional Volumetric Modulated Arc Therapy (VMAT), Intensity Modulated Proton Therapy (IMPT) and Spot-scanning Proton Arc (SPArc). Material and Methods: A patient's head CT data set was used as an in silico model. A series of targets (volume range from 0.3 cc to 33.03 cc) were inserted in the deep central and peripheral region, simulating targets with different sizes and locations. Three planning groups: IMPT, VMAT, and SPArc were created for dosimetric comparison purposes and a decision tree was built based on this in silico model. Nine patients with single brain metastases were retrospectively selected for validation. Multiple dosimetric metrics were analyzed to assess the plan quality, such as dose Conformity Index (CI) (ratio of the target volume to 100% prescription isodose volume); R50 (ratio of 50% prescription isodose volume to the target volume); V12Gy (volume of brain tissue minus GTV receiving 12 Gy), and mean dose of the normal brain. Normal tissue complication probability (NTCP) of brain radionecrosis (RN) was calculated using the Lyman-Kutcher-Burman (LKB) model and total treatment delivery time was calculated. Six physicians from different institutions participated in the blind survey to evaluate the plan quality and rank their choices. Results: The study showed that SPArc has a dosimetric advantage in the V12Gy and R50 with target volumes > 9.00 cc compared to VMAT and IMPT. A significant clinical benefit can be found in deep centrally located lesions larger than 20.00 cc using SPArc because of the superior dose conformity and mean dose reduction in healthy brain tissue. Nine retrospective clinical cases and the blind survey showed good agreement with the in silico dosimetric model and decision tree. Additionally, SPArc significantly reduced the treatment delivery time compared to VMAT (SPArc 184.46 ± 59.51s vs. VMAT: 1574.78 ± 213.65s). Conclusion: The study demonstrated the feasibility of using Proton beam therapy for single brain metastasis patients utilizing the SPArc technique. At the current stage of technological development, VMAT remains the current standard modality of choice for single lesion brain SRS. The in silico dosimetric model and decision tree presented here could be used as a practical clinical decision tool to assist the selection of the optimal treatment modality among VMAT, IMPT, and SPArc in centers that have both photon and proton capabilities.

16.
Infect Drug Resist ; 15: 2813-2824, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35677528

RESUMEN

Purpose: Metagenomic next-generation sequencing (mNGS) is a novel technique of pathogens detection that plays an increasingly important role in clinical practice. In this study, we explored the application value of mNGS in pulmonary infection combined with pleural effusion applied to samples of pleural effusion fluid. Patients and Methods: We reviewed 80 cases of pulmonary infection with pleural effusion between August 2020 and October 2021. Among them, 40 patients were placed in the mNGS group and underwent both culture and mNGS testing; the patients in the control group were only subjected to culture test. The effectiveness of mNGS was evaluated for microbial composition and diagnostic accuracy in every pleural effusion specimen type. Results: We found that the positive rate of mNGS was 70% (28/40). The comparison between mNGS and culture method resulted that the sensitivity was 100% (95% CI: 29.2-100%) and the specificity was 64.9% (95% CI: 47.5-79.8%). The positive predictive value of mNGS was 18.8% (95% CI, 13.0-26.3%), and the negative predictive value was 100%. The most commonly identified potential pathogens were bacteria, such as Streptococcus, Prevotella, Parvimonas, Porphyromonas and Gemella. The most detected fungal infection was Candida and Pneumocystis. A total of 11 patients were identified as mixed infection by mNGS. Treatment regimen adjustments were made according to mNGS results and the overall length of hospital stay in the mNGS group was shorter compared to that of the control group. Conclusion: In this study, mNGS produced higher positive rates than the culture method in detecting pathogens in the pleural effusion specimens. The technology performed satisfactorily, providing more diagnostic evidence and reducing the length of hospital stay.

17.
Nat Struct Mol Biol ; 29(6): 519-528, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35589838

RESUMEN

Plastins/fimbrins are conserved actin-bundling proteins contributing to motility, cytokinesis and other cellular processes by organizing strikingly different actin assemblies as in aligned bundles and branched networks. We propose that this ability of human plastins stems from an allosteric communication between their actin-binding domains (ABD1/2) engaged in a tight spatial association. Here we show that ABD2 can bind actin three orders of magnitude stronger than ABD1, unless the domains are involved in an equally strong inhibitory engagement. A mutation mimicking physiologically relevant phosphorylation at the ABD1-ABD2 interface greatly weakened their association, dramatically potentiating actin cross-linking. Cryo-EM reconstruction revealed the ABD1-actin interface and enabled modeling of the plastin bridge and domain separation in parallel bundles. We predict that a strong and tunable allosteric inhibition between the domains allows plastins to modulate the cross-linking strength, contributing to remodeling of actin assemblies of different morphologies defining the unique place of plastins in actin organization.


Asunto(s)
Actinas , Proteínas de Microfilamentos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Regulación Alostérica , Humanos , Glicoproteínas de Membrana/metabolismo , Proteínas de Microfilamentos/metabolismo
18.
Radiat Oncol ; 17(1): 87, 2022 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-35525993

RESUMEN

BACKGROUND: A new compact superconducting synchrocyclotron single-room proton solution delivers pulsed proton beams to each spot through several irradiation bursts calculated by an iterative layer delivery algorithm. Such a mechanism results in a new beam parameter, burst switching time (BST) in the total beam delivery time (BDT) which has never been studied before. In this study, we propose an experimental approach to build an accurate BDT and sequence prediction model for this new proton solution. METHODS: Test fields and clinical treatment plans were used to investigate each beam delivery parameter that impacted BDT. The machine delivery log files were retrospectively analyzed to quantitatively model energy layer switching time (ELST), spot switching time (SSWT), spot spill time (SSPT), and BST. A total of 102 clinical IMPT treatment fields' log files were processed to validate the accuracy of the BDT prediction model in comparison with the result from the current commercial system. Interplay effect is also investigated as a clinical application by comparing this new delivery system model with a conventional cyclotron accelerator model. RESULTS: The study finds that BST depends on the amount of data to be transmitted between two sequential radiation bursts, including a machine irradiation log file of the previous burst and a command file to instruct the proton system to deliver the next burst. The 102 clinical treatment fields showed that the accuracy of each component of the BDT matches well between machine log files and BDT prediction model. More specifically, the difference of ELST, SSWT, SSPT, and BST were (- 3.1 ± 5.7)%, (5.9 ± 3.9)%, (2.6 ± 8.7)%, and (- 2.3 ± 5.3)%, respectively. The average total BDT was about (2.1 ± 3.0)% difference compared to the treatment log files, which was significantly improved from the current commercial proton system prediction (58 ± 15)%. Compared to the conventional cyclotron system, the burst technique from synchrocyclotron effectively reduced the interplay effect in mobile tumor treatment. CONCLUSION: An accurate BDT and sequence prediction model was established for this new clinical compact superconducting synchrocyclotron single-room proton solution. Its application could help users of similar facilities better assess the interplay effect and estimate daily patient treatment throughput.


Asunto(s)
Terapia de Protones , Ciclotrones , Humanos , Terapia de Protones/métodos , Protones , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Estudios Retrospectivos
19.
Biochem Biophys Res Commun ; 601: 137-145, 2022 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-35247767

RESUMEN

Acute myeloid leukemia (AML) is the most common acute leukemia in adults, associated with poor prognosis and easy relapse of disease. Circular RNAs (circRNAs) were detected to be m6A modified and the role of m6A circRNAs has been reported in other diseases including cancers, however, their role has not been elucidated in AML yet. In the present study, we aimed to investigate the expression profiling of m6A circRNAs in AML. We performed m6A circRNAs microarray analysis to identify differentially expressed m6A circRNAs in bone marrow samples from AML patients and healthy individuals (control). Furthermore, bioinformatics analysis predicted the potential functions and relevant pathways that may be associated with the m6A circRNAs. The circRNA m6A methylation levels were found to be positively associated with the circRNAs expression, suggesting circRNA m6A modification could contribute to circRNA regulation in AML. Further analysis demonstrated that circRNA m6A modification might influence the circRNA-miRNA-mRNA co-expression network that may contribute to the circRNA regulatory network in AML. Our findings provide evidence of the differential expression profile of m6A circRNAs in AML, and circRNA m6A modification may contribute to circRNA regulatory function in AML.


Asunto(s)
Leucemia Mieloide Aguda , MicroARNs , Adenosina/análogos & derivados , Adulto , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética
20.
J Clin Lipidol ; 16(2): 220-226, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35241398

RESUMEN

BACKGROUND: Elevated lipoprotein (a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD). As clinical LDL cholesterol [LDL-C] incorporates cholesterol from Lp(a) [Lp(a)-C], there is interest in quantifying the contribution of Lp(a)-C to LDL-C given implications for risk assessment, diagnosis, and treatment. Estimating Lp(a)-C is subject to inaccuracies; measuring Lp(a) particle number [Lp(a)-P] is more accurate. OBJECTIVE: To capture how Lp(a) contributes to the concentration of atherogenic particles, we demonstrate a particle-based approach using readily available measures of Lp(a)-P and apolipoprotein B (apoB). METHODS: Using the Very Large Database of Lipids (VLDbL), we compared Lp(a)-P (nmol/L) with all apoB containing particles ("apoB-P"). apoB-P was calculated by converting apoB mass to molar concentration using the preserved molecular weight of apoB100 (512 kg/mol). We calculated the percentage of Lp(a)-P relative to apoB-P by Lp(a)-P deciles and stratified by triglycerides, LDL-C, and non-HDL-C. RESULTS: 158,260 patients from the VLDbL were included. The fraction Lp(a)-P/apoB-P increased with rising Lp(a)-P. Lp(a)-P comprised on average 3% of apoB containing particles among the study population and 15% at the highest Lp(a)-P decile. Lp(a)-P/apoB-P decreased at higher levels of triglycerides and LDL-C owing to larger contributions from VLDL and LDL. CONCLUSIONS: We demonstrate a particle-based approach to quantify the contribution of Lp(a) to all apoB-containing particles using validated and widely available clinical assays. This approach keeps in line with recommendations to move away from mass-based measurements of Lp(a) and prioritize more accurate particle-based measurements. Future research applying this method could define clinically meaningful thresholds and inform use in risk assessment and management.


Asunto(s)
Aterosclerosis , Hiperlipidemias , Apolipoproteínas B , Colesterol , LDL-Colesterol , Humanos , Lipoproteína(a) , Triglicéridos
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