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2.
BMC Health Serv Res ; 24(1): 291, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448911

RESUMO

BACKGROUND: Adults with sickle cell disease (SCD) suffer early mortality and high morbidity. Many are not affiliated with SCD centers, defined as no ambulatory visit with a SCD specialist in 2 years. Negative social determinants of health (SDOH) can impair access to care. HYPOTHESIS: Negative SDOH are more likely to be experienced by unaffiliated adults than adults who regularly receive expert SCD care. METHODS: Cross-sectional analysis of the SCD Implementation Consortium (SCDIC) Registry, a convenience sample at 8 academic SCD centers in 2017-2019. A Distressed Communities Index (DCI) score was assigned to each registry member's zip code. Insurance status and other barriers to care were self-reported. Most patients were enrolled in the clinic or hospital setting. RESULTS: The SCDIC Registry enrolled 288 Unaffiliated and 2110 Affiliated SCD patients, ages 15-45y. The highest DCI quintile accounted for 39% of both Unaffiliated and Affiliated patients. Lack of health insurance was reported by 19% of Unaffiliated versus 7% of Affiliated patients. The most frequently selected barriers to care for both groups were "previous bad experience with the healthcare system" (40%) and "Worry about Cost" (17%). SCD co-morbidities had no straightforward trend of association with Unaffiliated status. The 8 sites' results varied. CONCLUSION: The DCI economic measure of SDOH was not associated with Unaffiliated status of patients recruited in the health care delivery setting. SCDIC Registrants reside in more distressed communities than other Americans. Other SDOH themes of affordability and negative experiences might contribute to Unaffiliated status. Recruiting Unaffiliated SCD patients to care might benefit from systems adopting value-based patient-centered solutions.


Assuntos
Anemia Falciforme , Determinantes Sociais da Saúde , Adulto , Humanos , Estudos Transversais , Emoções , Anemia Falciforme/epidemiologia , Anemia Falciforme/terapia , Sistema de Registros
3.
Infection ; 52(3): 1125-1141, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38388854
4.
Hematol Oncol ; 42(1): e3240, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38050405

RESUMO

Patients affected by multiple myeloma (MM) have an increased risk of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection and subsequent coronavirus (20)19 disease (COVID-19)-related death. The changing epidemiological and therapeutic scenarios suggest that there has been an improvement in severity and survival of COVID-19 during the different waves of the pandemic in the general population, but this has not been investigated yet in MM patients. Here we analyzed a large cohort of 1221 patients with MM and confirmed SARS-CoV-2 infection observed between February 2020, and August 2022, in the EPICOVIDEHA registry from 132 centers around the world. Median follow-up was 52 days for the entire cohort and 83 days for survivors. Three-hundred and three patients died (24%) and COVID-19 was the primary reason for death of around 89% of them. Overall survival (OS) was significantly higher in vaccinated patients with both stable and active MM versus unvaccinated, while only a trend favoring vaccinated patients was observed in subjects with responsive MM. Vaccinated patients with at least 2 doses showed a better OS than those with one or no vaccine dose. Overall, according to pandemic waves, mortality rate decreased over time from 34% to 10%. In multivariable analysis, age, renal failure, active disease, hospital, and intensive care unit admission, were independently associated with a higher number of deaths, while a neutrophil count above 0.5 × 109 /L was found to be protective. This data suggests that MM patients remain at risk of SARS-CoV-2 infection even in the vaccination era, but their clinical outcome, in terms of OS, has progressively improved throughout the different viral phases of the pandemic.


Assuntos
COVID-19 , Mieloma Múltiplo , Humanos , SARS-CoV-2 , Pandemias , Mieloma Múltiplo/terapia , Sistema de Registros
5.
Leuk Lymphoma ; 65(2): 199-208, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37966980

RESUMO

Since the beginning of the COVID-19 pandemic, there has been an overall improvement in patient mortality. However, haematological malignancy patients continue to experience significant impacts from COVID-19, including high rates of hospitalization, intensive care unit (ICU) admissions, and mortality. In comparison to other haematological malignancy patients, individuals with chronic myeloid leukemia (CML) generally have better prognosis. This study, conducted using a large haematological malignancy patient database (EPICOVIDEHA), demonstrated that the majority of CML patients experienced mild infections. The decline in severe and critical infections over the years can largely be attributed to the widespread administration of vaccinations and the positive response they elicited. Notably, the mortality rate among CML patients was low and exhibited a downward trend in subsequent years. Importantly, our analysis provided confirmation of the effectiveness of vaccinations in CML patients.


Assuntos
COVID-19 , Neoplasias Hematológicas , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Pandemias , Leucemia Mielogênica Crônica BCR-ABL Positiva/epidemiologia , Hospitalização
6.
EClinicalMedicine ; 58: 101939, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37041967

RESUMO

Background: Nirmatrelvir/ritonavir treatment decreases the hospitalisation rate in immunocompetent patients with COVID-19, but data on efficacy in patients with haematological malignancy are scarce. Here, we describe the outcome of nirmatrelvir/ritonavir treatment in a large cohort of the latter patients. Methods: This is a retrospective cohort study from the multicentre EPICOVIDEHA registry (NCT04733729) on patients with haematological malignancy, who were diagnosed with COVID-19 between January and September 2022. Patients receiving nirmatrelvir/ritonavir were compared to those who did not. A logistic regression was run to determine factors associated with nirmatrelvir/ritonavir administration in our sample. Mortality between treatment groups was assessed with Kaplan-Meier survival plots after matching all the patients with a propensity score. Additionally, a Cox regression was modelled to detect factors associated with mortality in patients receiving nirmatrelvir/ritonavir. Findings: A total of 1859 patients were analysed, 117 (6%) were treated with nirmatrelvir/ritonavir, 1742 (94%) were treated otherwise. Of 117 patients receiving nirmatrelvir/ritonavir, 80% had received ≥1 anti-SARS-CoV-2 vaccine dose before COVID-19 onset, 13% of which received a 2nd vaccine booster. 5% were admitted to ICU. Nirmatrelvir/ritonavir treatment was associated with the presence of extrapulmonary symptoms at COVID-19 onset, for example anosmia, fever, rhinitis, or sinusitis (aOR 2.509, 95%CI 1.448-4.347) and 2nd vaccine booster (aOR 3.624, 95%CI 1.619-8.109). Chronic pulmonary disease (aOR 0.261, 95%CI 0.093-0.732) and obesity (aOR 0.105, 95%CI 0.014-0.776) were not associated with nirmatrelvir/ritonavir use. After propensity score matching, day-30 mortality rate in patients treated with nirmatrelvir/ritonavir was 2%, significantly lower than in patients with SARS-CoV-2 directed treatment other than nirmatrelvir/ritonavir (11%, p = 0.036). No factor was observed explaining the mortality difference in patients after nirmatrelvir/ritonavir administration. Interpretation: Haematological malignancy patients were more likely to receive nirmatrelvir/ritonavir when reporting extrapulmonary symptoms or 2nd vaccine booster at COVID-19 onset, as opposed to chronic pulmonary disease and obesity. The mortality rate in patients treated with nirmatrelvir/ritonavir was lower than in patients with targeted drugs other than nirmatrelvir/ritonavir. Funding: EPICOVIDEHA has received funds from Optics COMMIT (COVID-19 Unmet Medical Needs and Associated Research Extension) COVID-19 RFP program by GILEAD Science, United States (Project 2020-8223).

7.
J Hematol Oncol ; 16(1): 32, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37005697

RESUMO

Only few studies have analyzed the efficacy of tixagevimab/cilgavimab to prevent severe Coronavirus disease 2019 (COVID-19) and related complications in hematologic malignancies (HM) patients. Here, we report cases of breakthrough COVID-19 after prophylactic tixagevimab/cilgavimab from the EPICOVIDEHA registry). We identified 47 patients that had received prophylaxis with tixagevimab/cilgavimab in the EPICOVIDEHA registry. Lymphoproliferative disorders (44/47, 93.6%) were the main underlying HM. SARS-CoV-2 strains were genotyped in 7 (14.9%) cases only, and all belonged to the omicron variant. Forty (85.1%) patients had received vaccinations prior to tixagevimab/cilgavimab, the majority of them with at least two doses. Eleven (23.4%) patients had a mild SARS-CoV-2 infection, 21 (44.7%) a moderate infection, while 8 (17.0%) had severe infection and 2 (4.3%) critical. Thirty-six (76.6%) patients were treated, either with monoclonal antibodies, antivirals, corticosteroids, or with combination schemes. Overall, 10 (21.3%) were admitted to a hospital. Among these, two (4.3%) were transferred to intensive care unit and one (2.1%) of them died. Our data seem to show that the use of tixagevimab/cilgavimab may lead to a COVID-19 severity reduction in HM patients; however, further studies should incorporate further HM patients to confirm the best drug administration strategies in immunocompromised patients.


Assuntos
COVID-19 , Neoplasias Hematológicas , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/tratamento farmacológico , Anticorpos Monoclonais , Imunização Passiva , Sistema de Registros
8.
J Am Coll Cardiol ; 81(16): 1553-1564, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36889610

RESUMO

BACKGROUND: MK-0616 is an oral macrocyclic peptide inhibitor of proprotein convertase subtilisin/kexin type 9 (PCSK9) in development for the treatment of hypercholesterolemia. OBJECTIVES: This Phase 2b, randomized, double-blind, placebo-controlled, multicenter trial aimed to evaluate the efficacy and safety of MK-0616 in participants with hypercholesterolemia. METHODS: This trial was planned to include 375 adult participants with a wide range of atherosclerotic cardiovascular disease risk. Participants were assigned randomly (1:1:1:1:1 ratio) to MK-0616 (6, 12, 18, or 30 mg once daily) or matching placebo. The primary endpoints included percentage change from baseline in low-density lipoprotein cholesterol (LDL-C) at Week 8 and the proportion of participants with adverse events (AEs) and study intervention discontinuations due to AEs; participants were monitored for AEs for an additional 8 weeks after the 8-week treatment period. RESULTS: Of the 381 participants randomized, 49% were female, and the median age was 62 years. Among 380 treated participants, all doses of MK-0616 demonstrated statistically significant (P < 0.001) differences in least squares mean percentage change in LDL-C from baseline to Week 8 vs placebo: -41.2% (6 mg), -55.7% (12 mg), -59.1% (18 mg), and -60.9% (30 mg). AEs occurred in a similar proportion of participants in the MK-0616 arms (39.5% to 43.4%) as placebo (44.0%). Discontinuations due to AEs occurred in 2 or fewer participants in any treatment group. CONCLUSIONS: MK-0616 demonstrated statistically significant and robust, dose-dependent placebo-adjusted reductions in LDL-C at Week 8 of up to 60.9% from baseline and was well tolerated during 8 weeks of treatment and an additional 8 weeks of follow-up. (A Study of the Efficacy and Safety of MK-0616 [Oral PCSK9 Inhibitor] in Adults With Hypercholesterolemia [MK-0616-008]; NCT05261126).


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , LDL-Colesterol , Método Duplo-Cego , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/uso terapêutico , Serina Endopeptidases/uso terapêutico , Resultado do Tratamento
9.
Haematologica ; 108(1): 22-33, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35545919

RESUMO

Patients with acute myeloid leukemia (AML) are at high risk of dying from coronavirus disease 2019 (COVID-19). The optimal management of AML patients with COVID-19 has not been established. Our multicenter study included 388 adult AML patients diagnosed with COVID-19 between February 2020 and October 2021. The vast majority were receiving or had received AML treatment in the preceding 3 months. COVID-19 was severe in 41.2% and critical in 21.1% of cases. The chemotherapeutic schedule was modified in 174 patients (44.8%), delayed in 68 and permanently discontinued in 106. After a median follow-up of 325 days, 180 patients (46.4%) had died; death was attributed to COVID-19 (43.3%), AML (26.1%) or to a combination of both (26.7%), whereas in 3.9% of cases the reason was unknown. Active disease, older age, and treatment discontinuation were associated with death, whereas AML treatment delay was protective. Seventy-nine patients had a simultaneous AML and COVID-19 diagnosis, with better survival when AML treatment could be delayed (80%; P<0.001). Overall survival in patients with a diagnosis of COVID-19 between January 2020 and August 2020 was significantly lower than that in patients diagnosed between September 2020 and February 2021 and between March 2021 and September 2021 (39.8% vs. 60% vs. 61.9%, respectively; P=0.006). COVID-19 in AML patients was associated with a high mortality rate and modifications of therapeutic algorithms. The best approach to improve survival was to delay AML treatment, whenever possible.


Assuntos
COVID-19 , Hematologia , Leucemia Mieloide Aguda , Humanos , Adulto , Seguimentos , Teste para COVID-19 , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/tratamento farmacológico
10.
Blood ; 140(26): 2773-2787, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36126318

RESUMO

Limited data are available on breakthrough COVID-19 in patients with hematologic malignancy (HM) after anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. Adult patients with HM, ≥1 dose of anti-SARS-CoV-2 vaccine, and breakthrough COVID-19 between January 2021 and March 2022 were analyzed. A total of 1548 cases were included, mainly lymphoid malignancies (1181 cases, 76%). After viral sequencing in 753 cases (49%), the Omicron variant was prevalent (517, 68.7%). Most of the patients received ≤2 vaccine doses before COVID-19 (1419, 91%), mostly mRNA-based (1377, 89%). Overall, 906 patients (59%) received COVID-19-specific treatment. After 30-day follow-up from COVID-19 diagnosis, 143 patients (9%) died. The mortality rate in patients with the Omicron variant was 7.9%, comparable to other variants, with a significantly lower 30-day mortality rate than in the prevaccine era (31%). In the univariable analysis, older age (P < .001), active HM (P < .001), and severe and critical COVID-19 (P = .007 and P < .001, respectively) were associated with mortality. Conversely, patients receiving monoclonal antibodies, even for severe or critical COVID-19, had a lower mortality rate (P < .001). In the multivariable model, older age, active disease, critical COVID-19, and 2-3 comorbidities were correlated with a higher mortality, whereas monoclonal antibody administration, alone (P < .001) or combined with antivirals (P = .009), was protective. Although mortality is significantly lower than in the prevaccination era, breakthrough COVID-19 in HM is still associated with considerable mortality. Death rate was lower in patients who received monoclonal antibodies, alone or in combination with antivirals.


Assuntos
COVID-19 , Neoplasias Hematológicas , Adulto , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Teste para COVID-19 , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Anticorpos Monoclonais , Antivirais , Anticorpos Antivirais
12.
J Migr Health ; 6: 100110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35540795

RESUMO

Introduction: In the context of a health contingency such as the current COVID-19 pandemic, some groups may remain invisible, so that their health needs go unnoticed. These groups include migrants, asylum seekers, and refugees (MAR). In Mexico there is a network of migrant shelters (casas del migrante-CM) that provide humanitarian assistance, including access to heath care. Given the major role of the CM in caring for migrants, it was important to identify the main elements of their internal capacities, and of the external resources in the cities in which they are located, that contributed to their role in protecting MRA`s health during the COVID-19 pandemic. Methods: we use a comparative case study approach to understand, explain, and compare how internal capacities and external resources available to four CM in the north of Mexico, influenced the development and implementation of COVID-19 related strategies to protect MRA. The project took place during 2021 in Saltillo and Piedras Negras in Coahuila; Ciudad Juarez, Chihuahua, and in Monterrey, Nuevo Leon. A total of 18 in-depth interviews were performed with key actors from the CM, academia, health care services and international agencies. Results: We found a range from a total closure of one CM, to the continuation of operation of three of them, with differences in the strategies developed to provide services and avoid infections within the facilities. MARs' still face multiple barriers to exercise their right to health, and the response of local governments towards migration and health impacts the response that CM were able to implement. Conclusion: There is a need to strengthening the preparedness and response capacities and coordination mechanisms of local, state and federal authorities to attain their responsibilities in the provision of services directed to MAR, including access to health care.

13.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1385827

RESUMO

ABSTRACT: The present in vitro study determined the antibacterial effect of Coconut (Cocus nucifera) oil on Streptococcus mutans ATCC 25175. Cross-sectional and experimental study. Streptococcus mutans strain ATCC 25175 was seeded on Müeller- Hinton Blood Agar. The effect was determined by inhibition halo and the minimum inhibitory concentration, using procaine penicillin G as a positive control and standard suspension of Streptococcus mutans as a negative control. Twelve replicates per Coconut oil concentration (25 %, 50 % and 75 %) were performed. Coconut oil concentration at 25 % generated an inhibitory mean of 17 mm and 2.23x102 CFU, at 50 % a mean of 21.75 mm and 0.17 x 102 CFU, at 75 % a mean of 22 mm and 0 CFU, procaine penicillin G a mean of 14.25 mm and 0 CFU, the negative control gave a mean of 2.8 x 10 5 CFU. The Kruskal-Wallis non-parametric test detected a highly significant statistical difference of the three concentrations of Coconut oil (p < 0.01). The Mann-Whitney test with Bonferroni adjustment determined that the 50 % and 75 % concentration had similar inhibitory action and that both the 75 % concentration and procaine penicillin G gave a mean of 0 CFU. All concentrations of Coconut oil showed inhib itory action on Streptococcus mutans ATCC 25175. 75 % concentration showed the highest inhibitory mean and was the minimum inhibitory concentration that completely eliminated CFU.


RESUMEN: El presente estudio in vitro determinó el efecto antibacteriano del aceite de coco sobre Streptococcus mutans ATCC 25175. Estudio transversal y experimental. La cepa de Streptococcus mutans ATCC 25175 se sembró en Agar Sangre Müeller-Hinton. El efecto se determinó mediante el halo de inhibición y la concentración inhibitoria, utilizando la penicilina G procaína como control positivo y la suspensión estándar de Streptococcus mutans como control negativo. Se realizaron doce réplicas por cada concentración de aceite de coco (25 %, 50 % y 75 %). La concentración de aceite de coco al 25 % generó una media inhibitoria de 17 mm y 2,23 x 102 UFC, al 50 % una media de 21,75 mm y 0,17 x 102 UFC, al 75 % una media de 22 mm y 0 UFC, la penicilina G procaína una media de 14,25 mm y 0 UFC, el control negativo dio una media de 2,8 x 10 5 UFC. La prueba no paramétrica de Kruskal-Wallis detectó una diferencia estadística altamente significativa de las tres concentraciones de aceite de coco (p < 0,01). La prueba de Mann-Whitney con ajuste de Bonferroni determinó que las concentraciones del 50 % y del 75 % tenían una acción inhibidora similar y que tanto la concentración del 75 % como la penicilina G procaína daban una media de 0 UFC. Todas las concentraciones de aceite de coco mostraron una acción inhibitoria sobre Streptococcus mutans ATCC 25175. La concentración del 75 % mostró la media inhibitoria más alta y fue la concentración inhibitoria mínima que eliminó completamente las UFC.

14.
Arq. bras. neurocir ; 40(2): 113-119, 15/06/2021.
Artigo em Inglês | LILACS | ID: biblio-1362174

RESUMO

Objective The purpose of the present study is to demonstrate the usefulness of intraoperative ultrasound guidance as a technique for the assessment, in real time, of tumor resection and as a navigation aid during intra-axial brain lesion removal on patients admitted in the Neurosurgical Department at the Hospital Universitario de Caracas, Caracas, Venezuela, in 2018. Methods A total of 10 patients were enrolled, each with intra-axial brain lesions with no previous neurosurgical procedures and a mean age of 49 years old, ranging from 29 to 59 years old. Results A male predominance was observed with 7 cases (70%) over 3 female cases (30%). Six patients had lesions in the dominant hemisphere. The frontal lobe was the most commonly affected,with 5 cases, followed by the parietal lobe,with 4 cases. After craniotomy, ultrasound evaluation was performed previously to dural opening, during tumor resection and after tumor removal. The mean tumor size in axial, coronal and sagittal views was 3.72 cm, 3.08 cm and 3.00 cm, respectively, previously to dural opening with intraoperative ultrasound. The average tumor depth was 1.73 cm from the cerebral cortex. The location and removal duration from the beginning of the approach (ultrasound usage time) was 83.60 minutes, and the average surgery duration was 201 minutes. Navigation with intraoperative ultrasound served to resect intra-axial tumors more precisely and safely. There was no postoperative complication associated with the surgery in this series of cases. Conclusions Intraoperative ultrasound guidance for intra-axial subcortical tumor resection is a technique that serves as a surgical and anatomical orientation tool.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias Encefálicas/cirurgia , Monitorização Intraoperatória/métodos , Ultrassonografia , Neuronavegação/métodos , Glioma/cirurgia , Neoplasias Encefálicas/diagnóstico por imagem , Epidemiologia Descritiva , Procedimentos Neurocirúrgicos/métodos , Craniotomia/métodos , Glioma/fisiopatologia , Glioma/diagnóstico por imagem
15.
Appl Opt ; 59(27): 8160-8166, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32976396

RESUMO

Methods for measuring variations in diffuse surfaces using electronic speckle pattern interferometry (ESPI) are widely used and well known. In this research, we present an out-of-plane ESPI system coupled to a Michelson configuration to generate simultaneous parallel interferograms with different phase shifts. The system uses circular polarization states to generate parallel phase shifted interferograms. Due to the polarization states, the fringes do not experience a contrast reduction, thus avoiding measurement errors that affect spatial or temporal phase-shifting in interferometry. The basic operating principle of polarization modulation is described, and results that represent the temporal evolution of an aluminum plate are presented. The generation of two simultaneous patterns allows one to track the dynamic performance of the plate.

16.
Appl Opt ; 59(20): 6005-6011, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32672742

RESUMO

We have demonstrated a speckle out-of-plane interferometer that employs phase-stepping procedures by means of polarization modulation. The system generates circular polarization states with opposite signs at each arm of the system, which overlap at the output of the interferometer, to generate phase shifts operating a conventional linear polarizer; the emerging polarization states have been analyzed to obtain the shifts needed to process the optical phase. The phase-stepping technique is demonstrated with a two-step algorithm to measure out-of-plane displacement on a flat metal plate.

17.
Appl Opt ; 59(13): D148-D154, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400637

RESUMO

In this work, we present an optical and mechanical characterization of the behavior of an inhomogeneous biopolymer sample through the use of an in-plane electronic speckle pattern interferometer with a pulling system along the $y$y direction. The characterization of the sample subjected to stress comprised the acquisition of speckle patterns for 1360 states. Displacement maps and their corresponding strain maps were computed for every state. Since the information of the maps changes with size due to the sample being pulled at the upper end while it is clamped at the lower end, a scaling method to relate the maps to each other, point-to-point, is presented. The method allows the correct evaluation of sequential strain maps, which depicts the mechanical evolution of the material. Upon managing to relate the strain maps, it is possible to extract strain values for zones of interest from every map in order to build the respective stress-strain curves. Three stress-strain curves associated with three zones in the sample (upper, middle, and bottom) are constructed. When sequential displacement and deformation maps are optically obtained by the interferometer, we present a full-field characterization, along with the obtention stress-strain curves associated with the three zones of strain maps. The curves represent the inhomogeneous performance of the sample. Three different elastic moduli (${E_u} = 2.59\;{\rm MPa}$Eu=2.59MPa, ${E_m} = 1.97\;{\rm MPa}$Em=1.97MPa, and ${E_{b}} = 1.67\;{\rm MPa}$Eb=1.67MPa), associated with three respective zones, were obtained. The experimental results for a biopolymer sample here presented show that the technique, in conjunction with the scaling method, is a novel proposal to characterize inhomogeneous materials.


Assuntos
Fenômenos Biomecânicos , Biopolímeros/química , Interferometria/instrumentação , Interferometria/métodos , Algoritmos , Celulose/química , Simulação por Computador , Módulo de Elasticidade , Imagem Óptica , Estresse Mecânico
18.
J Clin Oncol ; 37(31): 2875-2882, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31536438

RESUMO

PURPOSE: Treatment abandonment because of enucleation refusal is a limitation of improving outcomes for children with retinoblastoma in countries with limited resources. Furthermore, many children present with buphthalmos and a high risk of globe rupture during enucleation. To address these unique circumstances, the AHOPCA II protocol introduced neoadjuvant chemotherapy with delayed enucleation. PATIENTS AND METHODS: Patients with advanced unilateral intraocular disease (International Retinoblastoma Staging System [IRSS] stage I) were considered for upfront enucleation. Those with diffuse invasion of the choroid, postlaminar optic nerve, and/or anterior chamber invasion received six cycles of adjuvant chemotherapy (vincristine, carboplatin, and etoposide). Patients with buphthalmos and those with a perceived risk for enucleation refusal and/or abandonment were given two to three cycles of chemotherapy before scheduled enucleation followed by adjuvant chemotherapy to complete six cycles, regardless of pathology. RESULTS: A total of 161 patients had unilateral IRSS stage I disease; 102 underwent upfront enucleation, and 59 had delayed enucleation. The estimated 5-year abandonment-sensitive event-free and overall survival rates for the group were 0.81 ± 0.03 and 0.86 ± 0.03, respectively. The 5-year estimated abandonment-sensitive event-free survival rates for patients undergoing upfront and delayed enucleation were 0.89 ± 0.03 and 0.68 ± 0.06, respectively (P = .001). Compared with AHOPCA I, abandonment for patients with IRSS stage I retinoblastoma decreased from 16% to 4%. CONCLUSION: AHOPCA describes the results of advanced intraocular retinoblastoma treated with neoadjuvant chemotherapy. In eyes with buphthalmos and patients with risk of abandonment, neoadjuvant chemotherapy can be effective when followed by enucleation and adjuvant chemotherapy. Our study suggests that this approach can save patients with buphthalmos from ocular rupture and might reduce refusal of enucleation and abandonment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Enucleação Ocular , Terapia Neoadjuvante , Neoplasias da Retina/terapia , Retinoblastoma/terapia , Tempo para o Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , América Central , Quimioterapia Adjuvante , Criança , Pré-Escolar , Progressão da Doença , Etoposídeo/administração & dosagem , Enucleação Ocular/efeitos adversos , Enucleação Ocular/mortalidade , Feminino , Humanos , Lactente , Masculino , Terapia Neoadjuvante/efeitos adversos , Terapia Neoadjuvante/mortalidade , Estadiamento de Neoplasias , Intervalo Livre de Progressão , Estudos Prospectivos , Neoplasias da Retina/mortalidade , Neoplasias da Retina/patologia , Retinoblastoma/mortalidade , Retinoblastoma/patologia , Fatores de Risco , Fatores de Tempo , Recusa do Paciente ao Tratamento , Vincristina/administração & dosagem
19.
Appl Opt ; 58(18): 4963-4968, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503818

RESUMO

In this work the sensitivity vector is analyzed for collimated and divergent oblique illumination for an out-of-plane arrangement. In the case of collimated illumination, the variation of the sensitivity vector components was considered and a geometric model was proposed for its evaluation. The geometry of the optical setup used allowed us to find sensitivity mostly along the pulling direction; the other two components of the sensitivity vector were relatively small. We measured the displacement induced only along the pulling direction. Errors in the displacement measurement associated with divergent and collimated illumination can be predicted when the sensitivity vector is considered constant. Experimental and theoretical results are presented for the out-of-plane electronic speckle pattern interferometer. The analyzed object was an aluminum plate.

20.
Rev. bioméd. (México) ; 30(2): 59-65, may.-ago. 2019. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1020480

RESUMO

RESUMEN La espondilitis tuberculosa (enfermedad de Pott) representa del 1-5% de los casos de tuberculosis. Se presenta un caso clínico de una paciente femenina de 14 años de edad con esta patología complicada con fractura de cuerpos vertebrales T4, T7, T8 y T9; a quien se le realizó un abordaje por vía posterior, consistente en laminectomía completa bilateral de T3, T4, T7, T8, T9 preservando las articulaciones facetarias, mas artrodesis instrumentada con ganchos sublaminares en T1-T2, colocación de alambres sublaminares T5 y T6, tornillos transpediculares en T11 y dos barras de titanio. Con excelentes resultados postoperatorios. Además, se discuten las diferentes vías de abordaje quirúrgico de esta patología.


ABSTRACT Tuberculous spondylitis (Pott's disease) represent 1-5% of tuberculosis cases. We present a clinical case of a female patient of 14 years of age with tuberculous spondylitis (Pott's disease) complicated with vertebral body fracture T4, T7, T8 and T9, who underwent a posterior approach, bilateral complete laminectomy of T3, T4, T7, T8, T9 preserving the facet joints, more arthrodesis instrumented with sublaminar hooks in T1-T2 placement of sublaminar wires T5 and T6 placement of transpedicular screws in T11, and two titanium bars. With excellent postoperative results. In addition, the different surgical approaches to this pathology are discussed.

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