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1.
Arq Bras Oftalmol ; 87(3): e20230038, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537047

RESUMO

PURPOSE: To assess the effect of the Coronavirus disease 2019 (COVID-19) pandemic on cataract surgery by residents who had mandatory surgical simulator training during residency. METHODS: In this retrospective, observational analytical study, the total number of cataract surgeries and surgical complications by all senior residents of 2019 (2019 class; prepandemic) and 2020 (2020 class; affected by the reduced number of elective surgeries due to the COVID-19 pandemic) were collected and compared. All residents had routine mandatory cataract surgery training on a virtual surgical simulator during residency. The total score obtained by these residents on cataract challenges of the surgical simulator was also evaluated. RESULTS: The 2020 and 2019 classes performed 1275 and 2561 cataract surgeries, respectively. This revealed a reduction of 50.2% in the total number of procedures performed by the 2020 class because of the pandemic. The incidence of surgical complications was not statistically different between the two groups (4.2% in the 2019 class and 4.9% in the 2020 class; p=0.314). Both groups also did not differ in their mean scores on the simulator's cataract challenges (p<0.696). CONCLUSION: Despite the reduction of 50.2% in the total number of cataract surgeries performed by senior residents of 2020 during the COVID-19 pandemic, the incidence of surgical complications did not increase. This suggests that surgical simulator training during residency mitigated the negative effects of the reduced surgical volume during the pandemic.


Assuntos
COVID-19 , Catarata , Internato e Residência , Humanos , Pandemias/prevenção & controle , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Competência Clínica
2.
Arq. bras. oftalmol ; 87(2): e2023, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1533798

RESUMO

ABSTRACT Purpose: To assess the effect of the coronavirus disease 2019 (COVID-19) pandemic on cataract surgery by residents who had mandatory surgical simulator training during residency. Methods: In this retrospective, observational analytical study, the total number of cataract surgeries and surgical complications by all senior residents of 2019 (2019 class; prepandemic) and 2020 (2020 class; affected by the reduced number of elective surgeries due to the COVID-19 pandemic) were collected and compared. All residents had routine mandatory cataract surgery training on a virtual surgical simulator during residency. The total score obtained by these residents on cataract challenges of the surgical simulator was also evaluated. Results: The 2020 and 2019 classes performed 1275 and 2561 cataract surgeries, respectively. This revealed a reduction of 50.2% in the total number of procedures performed by the 2020 class because of the pandemic. The incidence of surgical complications was not statistically different between the two groups (4.2% in the 2019 class and 4.9% in the 2020 class; p=0.314). Both groups also did not differ in their mean scores on the simulator's cataract challenges (p<0.696). Conclusion: Despite the reduction of 50.2% in the total number of cataract surgeries performed by senior residents of 2020 during the COVID-19 pandemic, the incidence of surgical complications did not increase. This suggests that surgical simulator training during residency mitigated the negative effects of the reduced surgical volume during the pandemic.

3.
Int J Biol Macromol ; 253(Pt 2): 126782, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37690638

RESUMO

Latex is a colloidal suspension derived from the Hevea brasiliensis tree, derived from natural rubber, poly(isoprene), and assorted constituents including proteins and phospholipids. These constituents are inherent to both natural rubber and latex serum. This investigation was undertaken to examine the impact of the deproteinization process on chemical and biological dynamics of natural rubber latex. Natural Rubber (NR) extracted from the pure latex (LNCP) was obtained through centrifugation, followed by six rounds of solvent purification (LP6). The structure was characterized using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), swelling test, surface zeta potential (ζ), scanning electron microscopy (SEM) and in vitro assay. The results revealed that the LP6 group presented decreased swelling kinetics, reduced cell adhesion and proliferation, and a smoother surface with decreased negative surface charge. Conversely, the LNCP group shown accelerated swelling, heightened adhesion and cellular growth, and a more negatively charged and rougher surface. As such, the attributes of latex serum and proteins have potential usage across numerous biomedical applications.


Assuntos
Hevea , Borracha , Borracha/química , Látex/química , Hevea/metabolismo , Fosfolipídeos/química , Microscopia Eletrônica de Varredura , Proteínas de Plantas/química
4.
Int J Biol Macromol ; 244: 125359, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37321441

RESUMO

Natural Rubber (NR), extracted from Hevea brasiliensis rubber trees, is a biocompatible biopolymer with properties that support in the tissue repair process. However, its biomedical applications are limited due to the presence of allergenic proteins, hydrophobicity, and unsaturated bonds. To overcome these limitations and contribute to the development of new biomaterials, this study aims to deproteinize, epoxidize, and subject NR to copolymerization by grafting with hyaluronic acid (HA), which is widely recognized for its bioactive properties in the medical field. The deproteinization, epoxidation, and graft copolymerization through the esterification reaction were confirmed by Fourier Transform Infrared Spectroscopy and Hydrogen Nuclear Magnetic Resonance Spectroscopy analysis. Thermogravimetry and Differential Scanning Calorimetry demonstrated that the grafted sample exhibited a lower degradation rate and a higher glass transition temperature, indicating strong intermolecular interactions. Moreover, contact angle measurement revealed that the grafted NR exhibited a high hydrophilic character. The results obtained suggest the formation of a novel material with great potential for application in biomaterials involved in tissue repair processes.


Assuntos
Hevea , Borracha , Borracha/química , Ácido Hialurônico , Materiais Biocompatíveis , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Endocr Connect ; 12(8)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37166408

RESUMO

Context: Congenital hypopituitarism is a genetically heterogeneous condition. Whole exome sequencing (WES) is a promising approach for molecular diagnosis of patients with this condition. Objectives: The aim of this study is to conduct WES in a patient with congenital hypopituitarism born to consanguineous parents, CDH2 screening in a cohort of patients with congenital hypopituitarism, and functional testing of a novel CDH2 variant. Design: Genomic DNA from a proband and her consanguineous parents was analyzed by WES. Copy number variants were evaluated. The genetic variants were filtered for population frequency (ExAC, 1000 genomes, gnomAD, and ABraOM), in silico prediction of pathogenicity, and gene expression in the pituitary and/or hypothalamus. Genomic DNA from 145 patients was screened for CDH2 by Sanger sequencing. Results: One female patient with deficiencies in growth hormone, thyroid-stimulating hormone, adrenocorticotropic hormone, luteinizing hormone, and follicle-stimulating hormone and ectopic posterior pituitary gland contained a rare homozygous c.865G>A (p.Val289Ile) variant in CDH2. To determine whether the p.Val289Ile variant in CDH2 affects cell adhesion properties, we stably transfected L1 fibroblast lines, labeled the cells with lipophilic dyes, and quantified aggregation. Large aggregates formed in cells expressing wildtype CDH2, but aggregation was impaired in cells transfected with variant CDH2 or non-transfected. Conclusion: A homozygous CDH2 allelic variant was found in one hypopituitarism patient, and the variant impaired cell aggregation function in vitro. No disease-causing variants were found in 145 other patients screened for CDH2 variants. Thus, CDH2 is a candidate gene for hypopituitarism that needs to be tested in different populations. Significance statement: A female patient with hypopituitarism was born from consanguineous parents and had a homozygous, likely pathogenic, CDH2 variant that impairs cell aggregation in vitro. No other likely pathogenic variants in CDH2 were identified in 145 hypopituitarism patients.

6.
Antibiotics (Basel) ; 12(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37237801

RESUMO

Drug delivery systems of natural antimicrobial compounds, such as copaiba oil (CO), have become relevant in the scientific community due to the recent prevalence of the public health complications related to antibiotic resistance. Electrospun devices act as an efficient drug delivery system for these bioactive compounds, reducing systemic side effects and increasing the effectiveness of the treatment. In this way, the present study aimed to evaluate the synergistic and antimicrobial effect of the direct incorporation of different concentrations of CO in a poly(L-co-D,L lactic acid) and natural rubber (NR) electrospun membrane. It was observed that CO showed bacteriostatic and antibacterial effects against S. aureus in antibiogram assays. The prevention of biofilm formation was confirmed via scanning electron microscopy. The test with crystal violet demonstrated strong bacteria inhibition in membranes with 75% CO. A decrease in hydrophilicity, observed in the swelling test, presented that the addition of CO promotes a safe environment for the recovery of injured tissue while acting as an antimicrobial agent. In this way, the study showed strong bacteriostatic effects of the CO incorporation in combination with electrospun membranes, a suitable feature desired in wound dressings in order to promote a physical barrier with prophylactic antimicrobial properties to avoid infections during tissue healing.

7.
Methods Mol Biol ; 2658: 53-64, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37024695

RESUMO

Candidiasis, infections caused by Candida spp., represents one of the most common nosocomial infections afflicting an expanding number of compromised patients. Antifungal therapeutic options are few and show limited efficacy. Moreover, biofilm formation is frequently associated with different manifestations of candidiasis and further complicates therapy. Thus, there is an urgent need for new effective therapeutic agents, particularly those with anti-biofilm activity. Here we describe the development of a novel, simple, fast, economical, and highly reproducible 384-well microtiter plate model for the formation of both Candida albicans and Candida auris biofilms and its application in high-throughput screening (HTS) techniques.


Assuntos
Candida , Candidíase , Humanos , Ensaios de Triagem em Larga Escala/métodos , Candida albicans , Antifúngicos/farmacologia , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Biofilmes , Testes de Sensibilidade Microbiana
8.
Nucleic Acids Res ; 51(8): 3770-3792, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36942484

RESUMO

During every cell cycle, both the genome and the associated chromatin must be accurately replicated. Chromatin Assembly Factor-1 (CAF-1) is a key regulator of chromatin replication, but how CAF-1 functions in relation to the DNA replication machinery is unknown. Here, we reveal that this crosstalk differs between the leading and lagging strand at replication forks. Using biochemical reconstitutions, we show that DNA and histones promote CAF-1 recruitment to its binding partner PCNA and reveal that two CAF-1 complexes are required for efficient nucleosome assembly under these conditions. Remarkably, in the context of the replisome, CAF-1 competes with the leading strand DNA polymerase epsilon (Polϵ) for PCNA binding. However, CAF-1 does not affect the activity of the lagging strand DNA polymerase Delta (Polδ). Yet, in cells, CAF-1 deposits newly synthesized histones equally on both daughter strands. Thus, on the leading strand, chromatin assembly by CAF-1 cannot occur simultaneously to DNA synthesis, while on the lagging strand these processes may be coupled. We propose that these differences may facilitate distinct parental histone recycling mechanisms and accommodate the inherent asymmetry of DNA replication.


Assuntos
Cromatina , Histonas , Histonas/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Fator 1 de Modelagem da Cromatina/genética , Fator 1 de Modelagem da Cromatina/metabolismo , Cromatina/genética , Replicação do DNA , DNA/genética
9.
J Refract Surg ; 39(1): 56-60, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36630436

RESUMO

PURPOSE: To assess anterior, posterior, and total corneal astigmatism in a large sample of Brazilian patients. METHODS: In this retrospective cross-sectional study, all patients whose corneas were imaged with the Galilei G6 (Ziemer Ophthalmology) between January 2017 and February 2019 at HOPE Eye Hospital, in Recife, Brazil, were eligible to participate. Anterior, posterior, and total corneal astigmatism values were collected and analyzed. RESULTS: The study included 3,253 eyes of 1,919 patients. The mean magnitude of the anterior, posterior, and total corneal astigmatism was 1.50 ± 1.11, 0.34 ± 0.15, and 1.29 ± 0.98 diopters (D), respectively. Corneal astigmatism was greater than 0.50 D in the anterior cornea of 86.3% of eyes (2,807 eyes) and in the posterior cornea of 13.2% of eyes (429 eyes). Vertical alignment of the steepest corneal meridian was observed in the anterior cornea of 74.5% of eyes (2,423 eyes) and in the posterior cornea of 93.1% of eyes (3,029 eyes). The correlation between the astigmatism magnitude of the anterior and posterior cornea was strong when the steep anterior meridian was aligned vertically (r = 0.720; P < .001), and absent when it was aligned horizontally (r = 0.102; P = .036). CONCLUSIONS: Corneal astigmatism values in the Brazilian population were similar to those found in other ethnicities, suggesting that toric calculators, nomograms, coefficients of adjustment, and formulas that were developed based on astigmatism values of other populations may be used in Brazilian patients with comparable accuracy. [J Refract Surg. 2023;39(1):56-60.].


Assuntos
Astigmatismo , Doenças da Córnea , Humanos , Astigmatismo/diagnóstico , Brasil/epidemiologia , Topografia da Córnea , Estudos Retrospectivos , Estudos Transversais , Córnea
10.
Microbes, Infection and Chemotherapy ; 3: e1855, 2023. tab, graf
Artigo em Inglês | CONASS, Coleciona SUS, Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1436776

RESUMO

Background. Chemokine and chemokine-receptor polymorphisms have been associated with protection against HIV infection and delayed progression to AIDS, whereas polymorphisms in IFNλ4 (formerly IL28B) have been associated with human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy (HAM) development. Evolutionary selection against ancestral genes differs among human populations, resulting in varying risks of acquiring and developing viral diseases. Methods. DNA samples from 434 patients infected with HIV-1 and/or co-infected with HTLV-1/-2, and samples from 74 HIV and HTLV non-infected individuals from São Paulo, Brazil, were divided into five groups: HIV-naïve, n=160; HIV-ART, n=180; HIV/HTLV-1, n=53; HIV/HTLV-2, n=41; and control, n=74. These samples were analyzed for CCR5-∆32deletion, CCR2-64I, SDF1-3'A, and IFNλ4 rs12979860 and rs8099917 single nucleotide polymorphisms using PCR and PCR-RFLP techniques. These polymorphisms' genotype and allele frequencies were calculated and compared among groups using logistic regression analysis. Results. All polymorphism profiles described in the literature were detected in this study. The wild-type genotype predominated in all genes analyzed except for IFNλ4 rs12979860. Statistical differences in allele frequencies among groups were detected in the CCR5 and CCR2 genes, with a high frequency of ∆32 in HIV-naïve vs. HIV-ART (OR 2.45, P=0.037) and a minus mutant allele A (CCR2-64I) in HIV-naïve vs. HIV/HTLV-1 (OR 1.90, P=0.048), HIV-ART vs. HIV/HTLV-1 (OR 2.62, P=0.003), and HIV/ART vs. HIV/HTLV-2 (OR 2.42, P=0.016). Conclusions. The polymorphism profiles detected in the study groups corroborate the profiles described in racial admixed populations. High CCR2-64I mutant allele frequencies were detected in HIV/HTLV-1/-2 co-infected individuals, and CCR5-∆32 showed predictive value for ART initiation. (AU)


Assuntos
Polimorfismo Genético , Brasil , Vírus Linfotrópico T Tipo 1 Humano , Vírus Linfotrópico T Tipo 2 Humano , HIV-1 , Quimiocinas , Receptores de Quimiocinas
11.
Sci Adv ; 8(30): eabo0517, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35895815

RESUMO

Nucleosome assembly requires the coordinated deposition of histone complexes H3-H4 and H2A-H2B to form a histone octamer on DNA. In the current paradigm, specific histone chaperones guide the deposition of first H3-H4 and then H2A-H2B. Here, we show that the acidic domain of DNA repair factor APLF (APLFAD) can assemble the histone octamer in a single step and deposit it on DNA to form nucleosomes. The crystal structure of the APLFAD-histone octamer complex shows that APLFAD tethers the histones in their nucleosomal conformation. Mutations of key aromatic anchor residues in APLFAD affect chaperone activity in vitro and in cells. Together, we propose that chaperoning of the histone octamer is a mechanism for histone chaperone function at sites where chromatin is temporarily disrupted.


Assuntos
Histonas , Nucleossomos , DNA/química , Reparo do DNA , Chaperonas de Histonas/genética , Chaperonas de Histonas/metabolismo , Histonas/metabolismo , Chaperonas Moleculares/genética
12.
Rev. esp. cardiol. (Ed. impr.) ; 75(5): 421-428, mayo 2022.
Artigo em Espanhol | IBECS | ID: ibc-205090

RESUMO

Introducción y objetivos: Existe poca información sobre la dilatación de la aurícula izquierda (AI) y los parámetros electrocardiográficos en deportistas. Métodos: Estudio observacional multicéntrico en deportistas de competición y controles. La dilatación de la AI se definió como un volumen indexado por área de superficie corporal ≥ 34ml/m2. Se estudió su relación con parámetros electrocardiográficos auriculares. Resultados: Se incluyó en total a 356 sujetos: 308 deportistas de competición (media de edad, 36,4±11,6 años) y 48 controles (49,3±16,1 años). Los deportistas de competición tenían un mayor volumen medio indexado de la AI (29,8±8,6 frente a 25,6±8,0ml/m2; p=0,006) y una mayor prevalencia de dilatación de la AI (113 [36,7%] frente a 5 [10,4%]; p <0,001), sin diferencias relevantes en cuanto a la duración de la onda P (106,3±12,5 frente a 108,2±7,7 ms; p=0,31), la prevalencia de bloqueo interauricular (40 [13,0%] frente a 4 [8,3%]; p=0,36) ni la puntuación Morphology-Voltage-P-wave duration (1,8±0,84 frente a 1,5±0,8; p=0,71). El entrenamiento competitivo se asoció de manera independiente con la dilatación de la AI (OR=14,7; IC95%, 4,7-44,0; p < 0,001), pero no con la duración de la onda P (OR=1,02; IC95%, 0,99-1,04), el bloqueo interauricular (OR=1,4; IC95%, 0,7-3,1) o la puntuación Morphology-Voltage-P-wave duration (OR=1,4; IC95%, 0,9-2,2). Conclusiones: La dilatación de la AI es frecuente en deportistas de competición, pero no se acompaña de una modificación relevante en los parámetros electrocardiográficos (AU)


Introduction and objectives: There are scarce data on left atrial (LA) enlargement and electrophysiological features in athletes. Methods: Multicenter observational study in competitive athletes and controls. LA enlargement was defined as LA volume indexed to body surface area ≥ 34mL/m2. We analyzed its relationship with atrial electrocardiography parameters. Results: We included 356 participants, 308 athletes (mean age: 36.4±11.6 years) and 48 controls (mean age: 49.3±16.1 years). Compared with controls, athletes had a higher mean LA volume index (29.8±8.6 vs 25.6±8.0mL/m2, P=.006) and a higher prevalence of LA enlargement (113 [36.7%] vs 5 [10.4%], P <.001), but there were no relevant differences in P-wave duration (106.3±12.5ms vs 108.2±7.7ms; P=.31), the prevalence of interatrial block (40 [13.0%] vs 4 [8.3%]; P=.36), or morphology-voltage-P-wave duration score (1.8±0.84 vs 1.5±0.8; P=.71). Competitive training was independently associated with LA enlargement (OR, 14.7; 95%CI, 4.7-44.0; P <.001) but not with P-wave duration (OR, 1.02; 95%CI, 0.99-1.04), IAB (OR, 1.4; 95%CI, 0.7-3.1), or with morphology-voltage-P-wave duration score (OR, 1.4; 95%CI, 0.9-2.2). Conclusions: LA enlargement is common in adult competitive athletes but is not accompanied by a significant modification in electrocardiographic parameters (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Atletas , Fibrilação Atrial , Eletrofisiologia Cardíaca , Átrios do Coração/diagnóstico por imagem , Eletrocardiografia
13.
J Comp Pathol ; 193: 51-58, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35487622

RESUMO

The objective of this study was to investigate the immunolabelling of acetylated histones and histone desacetylase (HDAC) enzymes in canine soft tissue sarcomas (STSs) and to correlate them with histological and clinical features in order to identify possible prognostic and therapeutic targets in these neoplasms. Fifteen canine STS samples were evaluated and were submitted to immunohistochemistry for acetylated histones 3 (H3) and 4 (H4) and deacetylating enzymes (HDAC1, HDAC2 and HDAC6). Intense immunolabelling of H4 was seen in comparison with H3. A strong positive correlation was observed between the H3 intensity score and the number of mitotic figures (P = 0.004, r = 0.7). Intense immunolabelling of HDAC1 was found in comparison to the expression of HDAC2 and HDAC6 in the evaluated STSs. This finding suggests that HDAC1 may be a potential target for HDAC inhibitors in STSs in dogs.


Assuntos
Doenças do Cão , Sarcoma , Animais , Cães , Histona Desacetilases/metabolismo , Histonas/metabolismo , Imuno-Histoquímica , Prognóstico , Sarcoma/veterinária
14.
J Refract Surg ; 37(7): 466-471, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34236908

RESUMO

PURPOSE: To assess the incidence and risk factors of Descemet membrane detachment due to laser application in femtosecond laser-assisted cataract surgery (FLACS). METHODS: In this retrospective case series, all patients who underwent FLACS with the LenSx system (Alcon Laboratories, Inc) were eligible to participate. The medical records were reviewed to collect data regarding potential risk factors related to Descemet membrane detachment, including patients' demographics, laser parameters, and ocular measurements. The eyes were separated into two groups based on the clinical diagnosis of Descemet membrane detachment as the femto-second laser was performing the corneal incisions. RESULTS: Five hundred ten eyes (304 patients) were included. Descemet membrane detachment occurred in 20 (3.9%) eyes of 16 (5.3%) patients. Four (1.3%) patients had a detachment in both eyes. In 16 (3.1%) eyes, the Descemet membrane detachment occurred in the secondary incision site. The eyes that had a detachment had a statistically lower mean endothelial cell density (2,193.40 ± 313.37 versus 2,385.08 ± 357.80 cells/ mm2; P = .019), and a statistically higher prevalence of corneal guttata (25.0% versus 8.8%; P = .015). None of the other analyzed variables statistically differed between the groups (P > .05). The risk of having Descemet membrane detachment was statistically higher among eyes with guttata (odds ratio = 3.47; P = .015) and in those with an endothelial cell density of less than 2,000 cells/mm2 (odds ratio = 3.26; P = .014). CONCLUSIONS: The incidence of Descemet membrane detachment due to laser application in FLACS was 3.9%, with the associated risk factors being endothelial cell density of less than 2,000 cells/mm2 and corneal guttata. [J Refract Surg. 2021;37(7):466-471.].


Assuntos
Extração de Catarata , Catarata , Terapia a Laser , Extração de Catarata/efeitos adversos , Lâmina Limitante Posterior , Humanos , Incidência , Terapia a Laser/efeitos adversos , Lasers , Estudos Retrospectivos , Fatores de Risco
15.
Sci Rep ; 11(1): 13048, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193882

RESUMO

Apex predators are threatened globally, and their local extinctions are often driven by failures in sustaining prey acquisition under contexts of severe prey scarcity. The harpy eagle Harpia harpyja is Earth's largest eagle and the apex aerial predator of Amazonian forests, but no previous study has examined the impact of forest loss on their feeding ecology. We monitored 16 active harpy eagle nests embedded within landscapes that had experienced 0 to 85% of forest loss, and identified 306 captured prey items. Harpy eagles could not switch to open-habitat prey in deforested habitats, and retained a diet based on canopy vertebrates even in deforested landscapes. Feeding rates decreased with forest loss, with three fledged individuals dying of starvation in landscapes that succumbed to 50-70% deforestation. Because landscapes deforested by > 70% supported no nests, and eaglets could not be provisioned to independence within landscapes > 50% forest loss, we established a 50% forest cover threshold for the reproductive viability of harpy eagle pairs. Our scaling-up estimate indicates that 35% of the entire 428,800-km2 Amazonian 'Arc of Deforestation' study region cannot support breeding harpy eagle populations. Our results suggest that restoring harpy eagle population viability within highly fragmented forest landscapes critically depends on decisive forest conservation action.

16.
Theranostics ; 11(11): 5313-5329, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859749

RESUMO

Rationale: Hypoxic regions (habitats) within tumors are heterogeneously distributed and can be widely variant. Hypoxic habitats are generally pan-therapy resistant. For this reason, hypoxia-activated prodrugs (HAPs) have been developed to target these resistant volumes. The HAP evofosfamide (TH-302) has shown promise in preclinical and early clinical trials of sarcoma. However, in a phase III clinical trial of non-resectable soft tissue sarcomas, TH-302 did not improve survival in combination with doxorubicin (Dox), possibly due to a lack of patient stratification based on hypoxic status. Therefore, we used magnetic resonance imaging (MRI) to identify hypoxic habitats and non-invasively follow therapies response in sarcoma mouse models. Methods: We developed deep-learning (DL) models to identify hypoxia, using multiparametric MRI and co-registered histology, and monitored response to TH-302 in a patient-derived xenograft (PDX) of rhabdomyosarcoma and a syngeneic model of fibrosarcoma (radiation-induced fibrosarcoma, RIF-1). Results: A DL convolutional neural network showed strong correlations (>0.76) between the true hypoxia fraction in histology and the predicted hypoxia fraction in multiparametric MRI. TH-302 monotherapy or in combination with Dox delayed tumor growth and increased survival in the hypoxic PDX model (p<0.05), but not in the RIF-1 model, which had a lower volume of hypoxic habitats. Control studies showed that RIF-1 resistance was due to hypoxia and not other causes. Notably, PDX tumors developed resistance to TH-302 under prolonged treatment that was not due to a reduction in hypoxic volumes. Conclusion: Artificial intelligence analysis of pre-therapy MR images can predict hypoxia and subsequent response to HAPs. This approach can be used to monitor therapy response and adapt schedules to forestall the emergence of resistance.


Assuntos
Hipóxia/tratamento farmacológico , Nitroimidazóis/farmacologia , Mostardas de Fosforamida/farmacologia , Pró-Fármacos/farmacologia , Sarcoma/tratamento farmacológico , Animais , Inteligência Artificial , Linhagem Celular Tumoral , Aprendizado Profundo , Modelos Animais de Doenças , Doxorrubicina/farmacologia , Ecossistema , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Camundongos , Camundongos Endogâmicos C3H , Camundongos SCID , Neoplasias de Tecidos Moles/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
17.
Food Chem ; 339: 127818, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32854038

RESUMO

Native extracts from orange peels were obtained by a conventional method using acetone and, an alternative method using ionic liquid (1-butyl-3-methylimidazolium chloride ([C4mim]Cl)). The bioaccessibilities and cellular uptakes of carotenoids, esters and chlorophylls were evaluated, since the influence of esterification on bioaccessibility and bioavailability is not well established. For this, the extracts were emulsified, submitted to in vitro simulated digestion model according to the INFOGEST protocol, followed by uptake by Caco-2 cells. Compounds were separated, identified and quantified by HPLC-PDA-MS/MS. After digestion, 22.0% and 26.2% of the total carotenoids and 45.9% and 68.7% of the chlorophylls were bioaccessible from the acetone and [C4mim]Cl extracts, respectively. The bioaccessibilities of xanthophylls and carotenes were significantly higher than those of the mono- and diesters. The uptake by Caco-2 cells varied from 130.2 to 131.9 ng/mg cell protein for total carotenoids and from 243.8 to 234.2 ng/mg cell protein for chlorophylls in the acetone and [C4mim]Cl extracts, respectively. In general, xanthophylls and esters were better absorbed than carotenes.


Assuntos
Carotenoides/farmacocinética , Fracionamento Químico/métodos , Clorofila/farmacocinética , Citrus sinensis/química , Disponibilidade Biológica , Células CACO-2 , Carotenoides/análise , Carotenoides/isolamento & purificação , Clorofila/análise , Clorofila/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Digestão , Ésteres/farmacocinética , Frutas/química , Humanos , Líquidos Iônicos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacocinética , Espectrometria de Massas em Tandem , Xantofilas/análise , Xantofilas/isolamento & purificação , Xantofilas/farmacocinética
18.
Int J Mol Sci ; 23(1)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35008721

RESUMO

Deficiency of 21-hydroxylase enzyme (CYP21A2) represents 90% of cases in congenital adrenal hyperplasia (CAH), an autosomal recessive disease caused by defects in cortisol biosynthesis. Computational prediction and functional studies are often the only way to classify variants to understand the links to disease-causing effects. Here we investigated the pathogenicity of uncharacterized variants in the CYP21A2 gene reported in Brazilian and Portuguese populations. Physicochemical alterations, residue conservation, and effect on protein structure were accessed by computational analysis. The enzymatic performance was obtained by functional assay with the wild-type and mutant CYP21A2 proteins expressed in HEK293 cells. Computational analysis showed that p.W202R, p.E352V, and p.R484L have severely impaired the protein structure, while p.P35L, p.L199P, and p.P433L have moderate effects. The p.W202R, p.E352V, p.P433L, and p.R484L variants showed residual 21OH activity consistent with the simple virilizing phenotype. The p.P35L and p.L199P variants showed partial 21OH efficiency associated with the non-classical phenotype. Additionally, p.W202R, p.E352V, and p.R484L also modified the protein expression level. We have determined how the selected CYP21A2 gene mutations affect the 21OH activity through structural and activity alteration contributing to the future diagnosis and management of CYP21A2 deficiency.


Assuntos
Genética Populacional , Mutação/genética , Esteroide 21-Hidroxilase/genética , Adolescente , Sequência de Aminoácidos , Brasil , Pré-Escolar , Simulação por Computador , Sequência Conservada , Feminino , Humanos , Lactente , Cinética , Masculino , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/genética , Portugal , Reprodutibilidade dos Testes , Esteroide 21-Hidroxilase/química
19.
J Feline Med Surg ; 23(2): 86-97, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32684120

RESUMO

OBJECTIVES: The aim of this study was to establish the safety and efficacy of a novel multidrug lomustine-based chemotherapeutic protocol for cats with high-grade multicentric or mediastinal lymphoma, in an area endemic for feline leukemia virus (FeLV). METHODS: This prospective study included owned cats, diagnosed (cytologically) with multicentric or mediastinal lymphoma and treated with the LOPH (lomustine, vincristine [Oncovin; Antibióticos do Brasil], prednisolone and hydroxydaunorubicin [doxorubicin]) protocol. A complete blood count was performed before every chemotherapy session and any significant abnormalities recorded as possible related toxicities. Median survival time (MST) and disease-free interval were estimated by Kaplan-Meier curves. RESULTS: Twenty-one cats were included in this study. Nineteen (90.5%) tested positive for FeLV and were therefore considered to have persistent viremia. Complete response was reported in 81% (n = 17/21), while three had partial remission and one had no response. Seven cats finished the induction protocol within 20-31 weeks (23.1 ± 4.5; median 20) and all seven received a maintenance protocol. The MST (lymphoma-related survival) for the 21 cats was 214 days. The MST was 214 days for cats with mediastinal lymphoma (n = 13), but it was not reached for multicentric lymphoma (n = 8; P = 0.9). The MST of cats with persistent FeLV antigenemia was 171 days. Grade I anorexia and vomiting occurred in 19% of the cats (n = 4/21). Hematologic toxicity was found in 100% of the cats at some point during their treatment, but it was mostly grade I or II. Neutropenia, thrombocytopenia and anemia occurred in 16/21, 21/21 and 15/21 cats, respectively. CONCLUSIONS AND RELEVANCE: The LOPH protocol was well tolerated by cats with lymphoma and persistent FeLV viremia, and resulted in a better MST than similar studies with other protocols. Novel studies and controlled trials are necessary in order to evaluate the efficacy of different protocols according to the lymphoma subtype, anatomic form and FeLV status.


Assuntos
Doenças do Gato , Leucemia Felina , Linfoma , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doenças do Gato/tratamento farmacológico , Gatos , Vírus da Leucemia Felina , Leucemia Felina/tratamento farmacológico , Leucemia Felina/epidemiologia , Linfoma/tratamento farmacológico , Linfoma/veterinária , Estudos Prospectivos , Vincristina
20.
J Cataract Refract Surg ; 45(7): 915-918, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31174986

RESUMO

PURPOSE: To assess the prevalence of macular abnormalities not suspected by the biomicroscopic fundus examination and identified only by macular optical coherence tomography (OCT) in the preoperative evaluation for cataract surgery in a large series of Brazilian patients. SETTING: Private practice, Recife, Brazil. DESIGN: Retrospective case series. METHODS: All eyes that had cataract surgery by the same physician between August 2014 and July 2016 were eligible. Excluded were eyes with a previous diagnosis of macular abnormalities, with a suspicious biomicroscopic fundus examination, and without OCT results. Based on the preoperative macular OCT, patients were divided into the following 2 groups: those with a normal OCT and those with an abnormal OCT. RESULTS: Nine hundred fifty-two eyes (614 patients) were included in the study. Macular OCT identified abnormalities in 47 eyes (4.9%) of 44 patients (7.2%). Thirty-one eyes (3.3%) had epiretinal membrane, 7 (0.7%) had age-related macular degeneration, 4 (0.4%) had intraretinal cysts, 4 (0.4%) had a lamellar hole, and 1 (0.1%) had a macular hole. Patients with an abnormal OCT had a statistically significant higher mean age (P = .004). CONCLUSION: In the preoperative evaluation for cataract surgery in Brazilian patients, 7.2% of those with a normal biomicroscopic fundus examination had macular abnormalities that were identified only by OCT.


Assuntos
Catarata/complicações , Macula Lutea/patologia , Doenças Retinianas/epidemiologia , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Extração de Catarata , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Prevalência , Doenças Retinianas/etiologia , Estudos Retrospectivos , Microscopia com Lâmpada de Fenda , Acuidade Visual , Adulto Jovem
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