Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 496
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nat Mater ; 22(8): 985-991, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37349393

RESUMO

The origin of nematicity in FeSe remains a critical outstanding question towards understanding unconventional superconductivity in proximity to nematic order. To understand what drives the nematicity, it is essential to determine which electronic degree of freedom admits a spontaneous order parameter independent from the structural distortion. Here we use X-ray linear dichroism at the Fe K pre-edge to measure the anisotropy of the 3d orbital occupation as a function of in situ applied stress and temperature across the nematic transition. Along with using X-ray diffraction to precisely quantify the strain state, we reveal a lattice-independent, spontaneously ordered orbital polarization within the nematic phase, as well as an orbital polarizability that diverges as the transition is approached from above. These results provide strong evidence that spontaneous orbital polarization serves as the primary order parameter of the nematic phase.

2.
Retina ; 44(4): 723-730, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37973042

RESUMO

PURPOSE: To evaluate the predictive characteristics of fellow-eye geographic atrophy (GA) without neovascularization in patients with unilateral Type 3 macular neovascularization. METHODS: This retrospective study included 84 patients who were diagnosed with unilateral Type 3 macular neovascularization. Patients who developed fellow-eye neovascularization and those exhibiting GA without neovascularization at the final follow-up were included in the neovascularization and GA groups, respectively. The patient demographics and baseline fellow-eye characteristics were compared between the two groups. RESULTS: The mean follow-up period was 40.5 ± 11.5 months after diagnosis. Patients included in the GA group (n = 28) were significantly older (mean 77.4 ± 5.2 years vs. 74.2 ± 5.8 years, P = 0.016), had significantly thinner subfoveal choroidal thickness (mean 109.4 ± 36.8 µ m vs. 173.1 ± 77.6 µ m, P < 0.001), and had a significantly higher incidence of baseline GA (39.3% vs. 16.1%, P = 0.019) than those included in the neovascularization group (n = 56). In the multivariate analysis, subfoveal choroidal thickness showed a close negative association with the risk of GA rather than neovascularization ( P = 0.004, ß = 0.982, 95% confidence interval = 0.970-0.994). CONCLUSION: In patients with unilateral Type 3 macular neovascularization, older age, the presence of GA, and a thin choroid in the fellow eye were found to be indicative of a higher probability of progression toward fellow-eye GA instead of neovascularization may be potential candidates for future complement inhibitor treatments targeting fellow-eye GA.


Assuntos
Neovascularização de Coroide , Atrofia Geográfica , Degeneração Macular , Humanos , Atrofia Geográfica/diagnóstico , Estudos Retrospectivos , Neovascularização de Coroide/diagnóstico , Angiofluoresceinografia , Degeneração Macular/diagnóstico , Seguimentos
3.
Nano Lett ; 23(24): 11409-11415, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38095312

RESUMO

A prominent characteristic of 2D magnetic systems is the enhanced spin fluctuations, which reduce the ordering temperature. We report that a magnetic field of only 1000th of the Heisenberg superexchange interaction can induce a crossover, which for practical purposes is the effective ordering transition, at temperatures about 6 times the Néel transition in a site-diluted two-dimensional anisotropic quantum antiferromagnet. Such a strong magnetic response is enabled because the system directly enters the antiferromagnetically ordered state from the isotropic disordered state, skipping the intermediate anisotropic stage. The underlying mechanism is achieved on a pseudospin-half square lattice realized in the [(SrIrO3)1/(SrTiO3)2] superlattice thin film that is designed to linearly couple the staggered magnetization to external magnetic fields by virtue of the rotational symmetry-preserving Dzyaloshinskii-Moriya interaction. Our model analysis shows that the skipping of the anisotropic regime despite finite anisotropy is due to the enhanced isotropic fluctuations under moderate dilution.

4.
Phys Rev Lett ; 131(18): 186701, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37977621

RESUMO

The Fe intercalated transition metal dichalcogenide (TMD), Fe_{1/3}NbS_{2}, exhibits remarkable resistance switching properties and highly tunable spin ordering phases due to magnetic defects. We conduct synchrotron x-ray scattering measurements on both underintercalated (x=0.32) and overintercalated (x=0.35) samples. We discover a new charge order phase in the overintercalated sample, where the excess Fe atoms lead to a zigzag antiferromagnetic order. The agreement between the charge and magnetic ordering temperatures, as well as their intensity relationship, suggests a strong magnetoelastic coupling as the mechanism for the charge ordering. Our results reveal the first example of a charge order phase among the intercalated TMD family and demonstrate the ability to stabilize charge modulation by introducing electronic correlations, where the charge order is absent in bulk 2H-NbS_{2} compared to other pristine TMDs.

5.
Graefes Arch Clin Exp Ophthalmol ; 261(2): 401-408, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36112220

RESUMO

PURPOSE: To compare the characteristics and incidence rates of lesion reactivation after anti-vascular endothelial growth factor (VEGF) treatment in type 3 macular neovascularization (MNV) with and without subretinal fluid (SRF) at baseline. METHODS: This retrospective study included 95 patients diagnosed with type 3 MNV. After the initial loading injections, re-treatment was performed when lesion reactivation occurred defined as the re-accumulation of subretinal or intraretinal fluid or the new development of a retinal/subretinal hemorrhage. The differences in the baseline characteristics and the incidence rates of lesion reactivation were compared between patients with SRF (SRF group, n = 42) and those without SRF (non-SRF group, n = 53). RESULTS: At diagnosis, the mean visual acuity was worse (0.68 ± 0.41 vs 0.50 ± 0.36; P = 0.032), mean central retinal thickness was greater (515.4 ± 145.9 µm vs 383.8 ± 105.5 µm; P < 0.001), and the incidence of focal retinal hemorrhages was higher (90.5% vs 66.0%; P = 0.005) in the SRF group than in the non-SRF group. In the SRF group, the first lesion reactivation was noted in 89.7% at a mean of 5.8 ± 4.4 months after the third injection. In the non-SRF group, the first lesion reactivation was noted in 70.6% at a mean of 6.1 ± 3.8 months. There was a significant difference in lesion reactivation between the two groups (P = 0.019). CONCLUSIONS: The difference in the baseline characteristics and incidence of lesion reactivation between type 3 MNV with and without SRF suggests that the presence of SRF may be indicative of more advanced disease with a high risk of visual deterioration. This result also suggests the need for more active treatment to preserve vision in patients with SRF.


Assuntos
Ranibizumab , Degeneração Macular Exsudativa , Humanos , Inibidores da Angiogênese , Fator A de Crescimento do Endotélio Vascular , Líquido Sub-Retiniano , Estudos Retrospectivos , Injeções Intravítreas , Neovascularização Patológica/tratamento farmacológico , Tomografia de Coerência Óptica , Degeneração Macular Exsudativa/complicações , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico
6.
Graefes Arch Clin Exp Ophthalmol ; 261(11): 3139-3148, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37314523

RESUMO

PURPOSE: We aim to evaluate the factors associated with the incidence of lesion reactivation after initial loading injections in patients with neovascular age-related macular degeneration (AMD). METHODS: This retrospective study included patients diagnosed with treatment-naïve neovascular AMD who received three loading injections of either ranibizumab or aflibercept. After the initial treatment, patients were followed up every 1-2 months during the first year and the follow-up interval was extended to 4 months during the second year. Retreatment was administered on an as-needed basis. The incidence and timing of lesion reactivation at 24 months after diagnosis were identified. In addition, Cox's proportional hazard model was used to evaluate the association of baseline factors with lesion reactivation. Lesion reactivation was defined re-accumulation of subretinal fluid/intraretinal fluid or the development of subretinal/intraretinal hemorrhage. RESULTS: A total of 284 patients (173 men and 111 women) were included in the study. The mean age of the patients was 70.5 ± 8.8 years. During the 24-month follow-up period, lesion reactivation was observed in 216 eyes (76.1%) at a mean of 8.2 ± 4.4 months after diagnosis. The incidence of lesion reactivation was 62.5% in extrafoveal macular neovascularization (MNV), 75.0% in juxtafoveal MNV, and 79.5% in subfoveal MNV. The extrafoveal MNV showed significantly lower incidence of lesion reactivation than subfoveal MNV (P = 0.041, hazard ratio = 0.64). CONCLUSIONS: Extrafoveal MNVs showed a lower incidence of lesion reactivation after initial treatment than subfoveal MNVs. This result should be considered when interpreting the results of clinical trials with different eligibility criteria regarding lesion location.

7.
Retina ; 43(8): 1264-1273, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36977322

RESUMO

PURPOSE: To evaluate the incidence and timing of pigment epithelial detachment (PED) and subretinal fluid (SRF) development in type 3 macular neovascularization. METHODS: This retrospective study included 84 patients who were diagnosed with treatment-naïve type 3 macular neovascularization who did not show SRF at diagnosis. All patients were initially treated with three loading injections of ranibizumab or aflibercept. After the initial loading injections, as-needed regimen was performed for retreatment. The development of either PED or SRF was identified. The incidence and timing of PED development in patients without PED at diagnosis and that of SRF development in patients with PED at diagnosis were evaluated. RESULTS: The mean follow-up period was 41.3 ± 20.7 months after diagnosis. Among the 32 patients without serous PED at diagnosis, PED developed in 20 (62.5%) at a mean of 10.9 ± 5.1 months after diagnosis. PED development was noted within 12 months in 15 patients (46.8%; 75.0% among the PED development cases). In 52 patients with serous PED and without SRF at diagnosis, 15 developed SRF (28.8%) at a mean of 11.2 ± 6.4 months after diagnosis. SRF development was noted within 12 months in nine patients (17.3%; 66.6% among the SRF development cases). CONCLUSION: PED and SRF developed in a substantial proportion of patients with type 3 macular neovascularization. The average period of development of these pathologic findings was within 12 months of diagnosis, suggesting the need for active treatment during the early treatment period to improve treatment outcomes.


Assuntos
Degeneração Macular , Descolamento Retiniano , Humanos , Inibidores da Angiogênese , Líquido Sub-Retiniano , Estudos Retrospectivos , Incidência , Injeções Intravítreas , Acuidade Visual , Ranibizumab , Degeneração Macular/diagnóstico , Descolamento Retiniano/diagnóstico , Neovascularização Patológica/tratamento farmacológico , Tomografia de Coerência Óptica
8.
Retina ; 43(8): 1274-1281, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36996466

RESUMO

PURPOSE: To analyze the clinical characteristics of drusenoid pigment epithelial detachment (PED) with subretinal fluid (SRF) and to evaluate the impact of SRF on the long-term visual and anatomical outcomes. METHODS: Forty-seven eyes with drusenoid PED (47 patients) who completed >24 months of follow-up were retrospectively analyzed. Intergroup comparisons of the visual and anatomical outcomes with and without SRF were made. RESULTS: The mean duration of follow-up was 32.9 ± 18.7 months. The group with drusenoid PED with SRF (14 eyes) showed significantly higher PED height (468 ± 130 µ m vs. 313 ± 88 µ m, P < 0.001), larger PED diameter (2,328 ± 953 µ m vs. 1,227 ± 882 µ m, P < 0.001), and larger PED volume (1.88 ± 1.73 mm 3 vs. 1.12 ± 1.35 mm 3 , P = 0.021) than that in the group with drusenoid PED without SRF (33 eyes) at baseline. No significant intergroup difference was found regarding the best-corrected visual acuity at the final visit. In addition, the incidence of complete retinal pigment epithelial and outer retinal atrophy (cRORA; 21.4%) and the development of macular neovascularization (MNV; 7.1%) for the group with drusenoid PED with SRF showed no difference compared with those (39.4% for cRORA development and 9.1% for MNV development) with drusenoid PED without SRF. CONCLUSION: The size, height, and volume of drusenoid PED were associated with the development of SRF. The SRF in drusenoid PED did not affect the visual prognosis or the development of macular atrophy during long-term follow-up.


Assuntos
Descolamento Retiniano , Líquido Sub-Retiniano , Humanos , Estudos Retrospectivos , Seguimentos , Epitélio Pigmentado da Retina/patologia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Descolamento Retiniano/tratamento farmacológico , Atrofia/patologia , Tomografia de Coerência Óptica , Inibidores da Angiogênese/uso terapêutico , Injeções Intravítreas
9.
BMC Ophthalmol ; 23(1): 282, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37332012

RESUMO

BACKGROUND: Information regarding incidence of treatment plan changes may be useful when discussing postoperative treatment plans for patients. Moreover, it may help establish a standardized postoperative treatment plan. This study aimed to evaluate the incidence of early complications requiring treatment plan changes in patients following vitreoretinal surgery and investigate its risk factors. METHODS: This single-center retrospective study included 465 patients who had undergone vitreoretinal surgery. The reasons, incidence, and timing of treatment plan changes within 14 days of surgery were identified. Potential factors associated with the changes, such as patient demographics, surgeon's experience, diagnoses, and type of surgery were also analyzed. RESULTS: The treatment plan was changed in 76 patients (16.3%) at a mean of 4.0 ± 3.2 days after vitreoretinal surgery. The reasons for the plan changes were increased intraocular pressure (IIOP) in 66(86.8%), intraocular inflammation in 2(2.6%), corneal edema in 3(3.9%), leakage from the sclerotomy wound in 3(3.9%) patients, and combined IIOP and intraocular inflammation in 2(2.6%). The date of discharge was postponed because of treatment plan changes in 17 patients (22.4%). The incidence of plan changes was higher in patients who underwent gas or oil tamponade (P < 0.001) and those who underwent surgery performed by less experienced surgeons (P = 0.034). CONCLUSIONS: Treatment plan was changed in 16.3% of patients after vitreoretinal surgery. The risk of treatment plan changes was associated with the surgeon's experience in vitreoretinal surgery and the type of surgery. These results should be considered when establishing standardized care plans for patients who require vitreoretinal surgery.


Assuntos
Glaucoma , Cirurgia Vitreorretiniana , Humanos , Estudos Retrospectivos , Cirurgia Vitreorretiniana/métodos , Incidência , Vitrectomia/métodos , Glaucoma/etiologia , Inflamação , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
10.
Proc Natl Acad Sci U S A ; 117(35): 21170-21174, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817559

RESUMO

Fe-based superconductors exhibit a diverse interplay between charge, orbital, and magnetic ordering. Variations in atomic geometry affect electron hopping between Fe atoms and the Fermi surface topology, influencing magnetic frustration and the pairing strength through changes of orbital overlap and occupancies. Here, we experimentally demonstrate a systematic approach to realize superconductivity without chemical doping in BaFe2As2, employing geometric design within an epitaxial heterostructure. We control both tetragonality and orthorhombicity in BaFe2As2 through superlattice engineering, which we experimentally find to induce superconductivity when the As-Fe-As bond angle approaches that in a regular tetrahedron. This approach to superlattice design could lead to insights into low-dimensional superconductivity in Fe-based superconductors.

11.
Proc Natl Acad Sci U S A ; 117(51): 32433-32442, 2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33288688

RESUMO

Ferroptosis is an iron-dependent regulated necrosis mediated by lipid peroxidation. Cancer cells survive under metabolic stress conditions by altering lipid metabolism, which may alter their sensitivity to ferroptosis. However, the association between lipid metabolism and ferroptosis is not completely understood. In this study, we found that the expression of elongation of very long-chain fatty acid protein 5 (ELOVL5) and fatty acid desaturase 1 (FADS1) is up-regulated in mesenchymal-type gastric cancer cells (GCs), leading to ferroptosis sensitization. In contrast, these enzymes are silenced by DNA methylation in intestinal-type GCs, rendering cells resistant to ferroptosis. Lipid profiling and isotope tracing analyses revealed that intestinal-type GCs are unable to generate arachidonic acid (AA) and adrenic acid (AdA) from linoleic acid. AA supplementation of intestinal-type GCs restores their sensitivity to ferroptosis. Based on these data, the polyunsaturated fatty acid (PUFA) biosynthesis pathway plays an essential role in ferroptosis; thus, this pathway potentially represents a marker for predicting the efficacy of ferroptosis-mediated cancer therapy.


Assuntos
Ácidos Graxos Insaturados/biossíntese , Ferroptose/fisiologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Ácido Araquidônico/genética , Ácido Araquidônico/metabolismo , Ácido Araquidônico/farmacologia , Carbolinas/farmacologia , Linhagem Celular Tumoral , Metilação de DNA , Dessaturase de Ácido Graxo Delta-5 , Elementos Facilitadores Genéticos , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Elongases de Ácidos Graxos/genética , Elongases de Ácidos Graxos/metabolismo , Ácidos Graxos Insaturados/genética , Ácidos Graxos Insaturados/metabolismo , Ferroptose/efeitos dos fármacos , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Metabolismo dos Lipídeos/genética , Regiões Promotoras Genéticas , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia
12.
Perfusion ; : 2676591231164878, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37083034

RESUMO

INTRODUCTION: Although thrombolytic therapy is the standard treatment for massive pulmonary thromboembolism (PTE), it is often ineffective in patients with circulatory collapse. Surgical embolectomy is another treatment option, but whether it is absolutely necessary is controversial. We sought to evaluate the outcomes of patients with massive PTE treated with intensive critical care including extracorporeal membrane oxygenation (ECMO) without thrombolytic therapy or surgical embolectomy. METHODS: We analyzed 39 patients who were treated for massive PTE from January 2011 to June 2019. Massive PTE was treated with anticoagulation and hemodynamic support at an intensive care unit. ECMO was applied in patients with circulatory collapse. The computed tomography (CT) obstruction index and the ratio of the right ventricle to left ventricle short-axis diameters (RV/LV) were measured using serial CT angiography to confirm changes in pulmonary emboli and RV strain. RESULTS: Twenty-one patients were in cardiogenic shock, and 15 of them needed cardiopulmonary resuscitation (CPR). Fifteen patients were treated with ECMO and nine of them were weaned successfully. The overall in-hospital mortality was 23% (9/39). On the follow-up CT scan after 6 months, residual PTE was observed in 10 patients and their median CT obstruction index was 6.25 % (range 2.5-35). The initial mean RV/LV ratio was 1.8 ± 0.47 and the value measured at follow-up CT decreased to less than 1 (0.9 ± 0.1). CONCLUSIONS: Intensive critical care with heparin alone and timely ECMO support without thrombolytic therapy could be an effective treatment option in patients with acute massive PTE.

13.
Clin Endocrinol (Oxf) ; 96(4): 521-530, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34647340

RESUMO

OBJECTIVE: This study aimed to investigate the impact of indices of adrenal venous sampling (AVS) on postsurgical outcomes in patients with primary aldosteronism (PA). DESIGN AND PATIENTS: This retrospective study determined biochemical and clinical outcomes based on ACTH-stimulated AVS parameters (lateralisation index [LI], contralateral ratio [CLR], and ipsilateral ratio [ILR]) in 251 patients with PA at 3 months after surgery. RESULTS: Modified complete biochemical success was achieved in 8 of 12 (66.7%) patients with LI = 3-4, 39 of 47 (83.0%) with LI = 4-10, and 155 of 169 (91.7%) with LI ≥ 10 (p = .004 for trend). Modified complete biochemical success was achieved in 29 of 38 (76.3%) patients with CLR ≥ 1 and ILR ≤ 2, 73 of 86 (84.9%) with CLR = 0.25-1 and ILR > 2, and 100 of 104 (96.2%) with CLR < 0.25 and ILR > 2 (p = .001 for trend). After adjusting for confounders, modified complete biochemical success was associated with an LI ≥ 10 (odds ratio [OR] = 6.32; 95% confidence interval [CI] = 1.33-29.93) using LI = 3-4 as a reference and combined CLR < 0.25 and ILR > 2 (OR = 11.49; 95% confidence interval [CI] = 2.49-53.01) using combined CLR ≥ 1 and ILR ≤ 2 as a reference. Using combined CLR ≥ 1 and ILR ≤ 2 as a reference, complete clinical success was associated with combined CLR < 0.25 and ILR > 2 (OR = 3.10; 95% CI = 1.03-9.28) and combined CLR = 0.25-1 and ILR > 2 (OR = 4.92; 95% CI = 1.64-14.76). CONCLUSION: LI ≥ 10 may be appropriate for achieving biochemical success. With ILR > 2, CLR < 0.25, and CLR < 1 may be appropriate for achieving biochemical and clinical success, respectively.


Assuntos
Hiperaldosteronismo , Glândulas Suprarrenais , Adrenalectomia , Hormônio Adrenocorticotrópico , Aldosterona , Humanos , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/cirurgia , Estudos Retrospectivos
14.
Phys Rev Lett ; 129(2): 027203, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867461

RESUMO

Symmetric anisotropic interaction can be ferromagnetic and antiferromagnetic at the same time but for different crystallographic axes. We show that the competition of anisotropic interactions of orthogonal irreducible representations can be a general route to obtain new exotic magnetic states. We demonstrate it here by observing the emergence of a continuously tunable 12-layer spatial spin modulation when distorting the square-lattice planes in the quasi-two-dimensional antiferromagnetic Sr_{2}IrO_{4} under in situ shear strain. This translation-symmetry-breaking phase is a result of an unusual strain-activated anisotropic interaction which is at the fourth order and competing with the inherent quadratic anisotropic interaction. Such a mechanism of competing anisotropy is distinct from that among the ferromagnetic, antiferromagnetic, and/or the Dzyaloshinskii-Moriya interactions, and it could be widely applicable and highly controllable in low-dimensional magnets.

15.
Phys Rev Lett ; 129(18): 187201, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36374692

RESUMO

The number of atomic layers confined in a two-dimensional structure is crucial for the electronic and magnetic properties. Single-layer and bilayer J_{eff}=1/2 square lattices are well-known examples where the presence of the extra layer turns the XY anisotropy to the c-axis anisotropy. We report on experimental realization of a hybrid SrIrO_{3}/SrTiO_{3} superlattice that integrates monolayer and bilayer square lattices in one layered structure. By synchrotron x-ray diffraction, resonant x-ray magnetic scattering, magnetization, and resistivity measurements, we found that the hybrid superlattice exhibits properties that are distinct from both the single-layer and bilayer systems and cannot be explained by a simple addition of them. In particular, the entire hybrid superlattice orders simultaneously through a single antiferromagnetic transition at temperatures similar to the bilayer system but with all the J_{eff}=1/2 moments mainly pointing in the ab plane similar to the single-layer system. The results show that bringing monolayer and bilayer with orthogonal properties in proximity to each other in a hybrid superlattice structure is a powerful way to stabilize a unique state not obtainable in a uniform structure.

16.
Biotechnol Bioeng ; 119(12): 3584-3595, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36109834

RESUMO

Modern biotechnological laboratories are equipped with advanced parallel mini-bioreactor facilities that can perform sophisticated cultivation strategies (e.g., fed-batch or continuous) and generate significant amounts of measurement data. These systems require not only optimal experimental designs that find the best conditions in very large design spaces, but also algorithms that manage to operate a large number of different cultivations in parallel within a well-defined and tightly constrained operating regime. Existing advanced process control algorithms have to be tailored to tackle the specific issues of such facilities such as: a very complex biological system, constant changes in the metabolic activity and phenotypes, shifts of pH and/or temperature, and metabolic switches, to name a few. In this study we implement a model predictive control (MPC) framework to demonstrate: (1) the challenges in terms of mathematical model structure, state, and parameter estimation, and optimization under highly nonlinear and stiff dynamics in biological systems, (2) the adaptations required to enable the application of MPC in high throughput bioprocess development, and (3) the added value of MPC implementations when operating parallel mini-bioreactors aiming to maximize the biomass concentration while coping with hard constrains on the dissolved oxygen tension profile.


Assuntos
Escherichia coli , Ensaios de Triagem em Larga Escala , Escherichia coli/genética , Reatores Biológicos , Biotecnologia , Biomassa
17.
Graefes Arch Clin Exp Ophthalmol ; 260(10): 3231-3239, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35612614

RESUMO

PURPOSE: To investigate the incidence, risk factors, and their influence on visual outcomes of subretinal hemorrhage (SRH) in patients with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy(PCV) who discontinue treatment. METHODS: This retrospective study included 148 patients with nAMD and PCV who discontinued treatment. The development of a 3-disc area or greater extent of SRH after treatment discontinuation was identified. Visual acuity at the final visit was compared between patients with and those without SRH. Factors associated with SRH were then analyzed. RESULTS: During the mean 56.8 ± 18.2 months of follow-up, treatment was discontinued at a mean 24.1 ± 16.3 months after diagnosis. SRH developed in 24 (16.2%) patients at a mean 21.5 ± 17.6 months after treatment discontinuation. The visual acuity at the final follow-up was significantly worse in patients with SRH than in those without SRH (P < 0.001). There was a significant difference in the incidence of SRH among the different types of macular neovascularization (MNV) (P = 0.024). In particular, the incidence of type 3 MNV was relatively high (36.0%). CONCLUSIONS: The development of SRH may lead to very poor visual prognosis in patients who discontinue treatment. The high risk of SRH in type 3 MNV suggests the need for caution when choosing treatment discontinuation in cases of type 3 MNV.


Assuntos
Neovascularização de Coroide , Degeneração Macular , Pólipos , Degeneração Macular Exsudativa , Corioide/irrigação sanguínea , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/epidemiologia , Angiofluoresceinografia , Humanos , Pólipos/diagnóstico , Pólipos/tratamento farmacológico , Hemorragia Retiniana/induzido quimicamente , Hemorragia Retiniana/diagnóstico , Hemorragia Retiniana/epidemiologia , Estudos Retrospectivos , Acuidade Visual , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico
18.
Graefes Arch Clin Exp Ophthalmol ; 260(3): 839-848, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34515840

RESUMO

PURPOSE: To evaluate morphologic changes of choroidal neovascularization (CNV) on optical coherence tomography angiography (OCTA) during the nonexudative period and to correlate the features and timing of recurrence in neovascular age-related macular degeneration. (AMD). METHODS: Two hundred thirty-eight eyes with type 1 CNV were retrospectively reviewed. For cases with exudative recurrence, OCTA images were tracked for analysis between the recurrences. Qualitative parameters of morphologic changes of CNV on OCTA, including tiny branching vessels, anastomotic loops, peripheral vascular arcade, and perilesional halo, were correlated with the features of exudative recurrence. RESULTS: Exudative recurrence was identified in 163 cases, and among them, nonexudative morphological changes in CNV were identified using OCTA in 45 cases. For the cases with nonexudative changes on OCTA, exudative recurrence eventually developed within 0.5-3.5 months (mean, 2.3 ± 2.0 months) after identifying morphologic changes OCTA. The following changes in CNV were revealed on OCTA: tiny branching vessels in 53.3% (24/45) of cases, anastomotic loops in 40.0% (18/45), peripheral vascular arcades in 44.4% (20/45), and perilesional halo in 35.6% (16/45). Among the morphologic parameters, development of tiny branching vessels was significantly associated with early exudative recurrence (1.5 ± 1.2 months, p = 0.019), higher incidence of intraretinal fluid (IRF) (p = 0.016), and subretinal or subretinal pigment epithelial hemorrhage (p = 0.023) at recurrence, compared with other morphologic changes. CONCLUSION: Development of tiny branching vessels of CNV on OCTA during the nonexudative period was associated with early exudative recurrence, including IRF or hemorrhage. Identifying the nonexudative changes of CNV on OCTA might predict exudative recurrence and provide additional parameters for monitoring neovascular AMD.


Assuntos
Neovascularização de Coroide , Degeneração Macular Exsudativa , Inibidores da Angiogênese/uso terapêutico , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/tratamento farmacológico , Angiofluoresceinografia/métodos , Humanos , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Fator A de Crescimento do Endotélio Vascular , Acuidade Visual , Degeneração Macular Exsudativa/complicações , Degeneração Macular Exsudativa/diagnóstico
19.
Retina ; 42(6): 1028-1037, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35152248

RESUMO

PURPOSE: To evaluate the incidence and characteristics of bacillary layer detachment (BALAD) in neovascular age-related macular degeneration. METHODS: This retrospective study was performed at Kim's Eye Hospital in South Korea. Patients who were diagnosed with neovascular age-related macular degeneration between January 2017 and December 2017 were included. The incidence of BALAD was compared among different types of macular neovascularization (MNV). The best-corrected visual acuity and central retinal thickness at diagnosis were compared between patients showing BALAD at diagnosis and those who did not. RESULTS: Among the 442 patients included, BALAD was observed in 20 patients (4.5%). There was a significant difference in the incidence of BALAD between Type 1 MNV (2.7%), Type 2 MNV (12.5%), and Type 3 MNV (0%) (P < 0.001). The best-corrected visual acuity was significantly worse (mean 1.26 ± 0.79 vs. 0.62 ± 0.50, P = 0.001), and the central retinal thickness was significantly greater (mean 648.2 ± 211.1 µm vs. 464.0 ± 175.5 µm, P < 0.001) in patients with BALAD than in those without it. After antivascular endothelial growth factor therapy, all BALADs resolved. CONCLUSION: This study first reported the incidence of the BALAD in neovascular age-related macular degeneration in a Korean population. The incidence of BALAD was the highest in Type 2 MNVs. Bacillary layer detachment generally develops in eyes with great macular thickness and poor visual acuity.


Assuntos
Degeneração Macular , Degeneração Macular Exsudativa , Inibidores da Angiogênese/uso terapêutico , Angiofluoresceinografia , Humanos , Injeções Intravítreas , Degeneração Macular/complicações , Degeneração Macular/diagnóstico , Degeneração Macular/epidemiologia , Neovascularização Patológica/tratamento farmacológico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular , Acuidade Visual , Degeneração Macular Exsudativa/complicações , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico
20.
Acta Radiol ; 63(1): 48-58, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33356351

RESUMO

BACKGROUND: The inferior phrenic artery (IPA) is the most common extrahepatic feeder for hepatocellular carcinoma (HCC) during transhepatic arterial chemoembolization (TACE). PURPOSE: To compare the incidence of diaphragmatic weakness in patients with HCC after TACE of the right IPA conducted using either N-butyl cyanoacrylate (NBCA) or gelatin sponge particles. MATERIAL AND METHODS: Medical records of 111 patients who underwent TACE of the right IPA using NBCA were retrospectively reviewed and compared with data from 135 patients with IPA embolization using gelatin sponge particles. RESULTS: The incidence of diaphragmatic weakness after the initial TACE procedure did not significantly differ between the groups (NBCA group 16.2%; gelatin sponge group 20.7%; P = 0.458). Five patients in the NBCA group and 11 in the gelatin sponge group showed spontaneous resolution of diaphragmatic weakness after a mean period of 3.5 months. Diaphragmatic weakness developed after the initial follow-up visit in 17 patients from the gelatin sponge group due to repeated TACE of the right IPA (mean 2.4 sessions; range 2-4 sessions), while it spontaneously developed without additional TACE procedures in one patient from the NBCA group. Permanent diaphragmatic weakness was less common in the NBCA than in the gelatin sponge group (12.6% and 25.2%, respectively; P = 0.017). The complete response rate did not significantly differ between the groups (NBCA group 16.2%; gelatin sponge group 25.9%; P = 0.065). CONCLUSION: Use of NBCA rather than gelatin sponge particles for TACE of the right IPA resulted in a lower incidence of permanent diaphragmatic weakness.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/efeitos adversos , Diafragma/irrigação sanguínea , Diafragma/fisiopatologia , Embucrilato/efeitos adversos , Esponja de Gelatina Absorvível/efeitos adversos , Neoplasias Hepáticas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA