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1.
Appl Opt ; 62(14): 3567-3573, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37706971

RESUMO

In this paper, a photonic crystal (PhC) based 1×2 demultiplexer is designed to work efficiently at 1550n m, which is the operating wavelength of optical communication. In designing a 1×2 demultiplexer, the PhC structure employs Y-shaped square-lattice silicon rods with air as its basis in accordance with the principle of beam interference. This study presents a 15×15 rod-based PhC optimized structure with air as its background. Several distinct phase studies are carried out making use of a wide variety of lattice constant and refractive index values of PhCs. The design achieves enhanced performance in accordance with parameters such as having higher contrast ratio of 15.64 dB, high transmission efficiency of 77.92%, fast response time of 15.03 fs, and low insertion loss of 1.08 dB with optimal values for refractive index (RI), silicon rod radius, and lattice constant. The results of the simulation that used the finite-difference-time-domain technique illustrate the good performance of this structure, which exhibits a higher contrast ratio and bit rate, average transmitted power, and fewer power losses.

4.
Case Rep Hematol ; 2020: 8822670, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33489389

RESUMO

Acute myeloid leukemia (AML) with inv(16)(p13.1q22) resulting in CBFB-MYH11 fusion is associated with a favorable prognosis. The presence of a KIT mutation modifies it to an intermediate prognosis. Additionally, inv(16) can cooperate with other genetic aberrations to further increase cell proliferation. Coexistence of inv(16) and t(9;22) is extremely rare (20 cases). We present a case of a 55-year-old male with elevated white blood cell count. Bone marrow evaluation and flow cytometry analysis were compatible with AML with monocytic features. Cytogenetic studies revealed two-related clones, a minor clone with inv(16) and a major clone with concurrent inv(16) and t(9;22) rearrangements. Fluorescent in situ hybridization studies confirmed these rearrangements. Molecular analysis detected a p190 BCR-ABL1 transcript protein. KIT mutations were negative. The patient was initially treated with standard induction regimen; 7 daily doses of cytarabine from day 1-day 7, 3 daily doses of daunorubicin from day 1-day 3, and 1 dose of Mylotarg (gemtuzumab ozogamicin) on day 1. The detection of t(9;22) led to the addition of daily doses of dasatinib (tyrosine kinase inhibitor) from day 7 onwards. The patient achieved complete remission on day 45. During his treatment course, he acquired disseminated Fusarium infection. Day 180 bone marrow evaluation revealed florid relapse with 64% blasts. Cytogenetic study showed clonal evolution of the inv(16) clone with no evidence of the t(9;22) subclone. Eventually, bone marrow transplantation was contraindicated, and the patient was transferred to palliative care. Literature review revealed that AML with co-occurrence of CBFB-MYH11 and BCR-ABL1 gene rearrangements was involved by only a small number of cases with de novo and therapy-related AML. Most cases were in myeloid blast crisis of chronic myeloid leukemia (CML). Treatment and prognosis among the de novo AML cases varied and majority of them achieved clinical remission. In contrast, these cytogenetic abnormalities in the blast phase of CML had a poor prognosis. As the prognosis and management of AML is dependent upon the underlying genetic characteristics of the neoplasm, it is imperative to include clinical outcome with such rare combinations of genetic alterations.

5.
Case Rep Cardiol ; 2019: 5404365, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428481

RESUMO

Takotsubo cardiomyopathy (TCM), also known as broken heart syndrome or stress-induced cardiomyopathy, is a rare condition with an estimated incidence of 0.02% of all hospitalizations in United States and 2% of all acute coronary syndrome presentations. TCM predominately presents as a transient wall motion abnormality of the left ventricular apex due to emotional or physical stress. Cardiac rupture in the setting of TCM is an extremely rare phenomenon with limited published case reports. We present a case of a 75-year-old female who had cardiac rupture secondary to TCM and performed a literature review using Ovid MEDLINE for published cases showing this association. After the literature review, we found 20 cases showing this association, which are listed in a tabular fashion.

6.
J Atr Fibrillation ; 11(2): 2094, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30505385

RESUMO

BACKGROUND: There is limited data regarding effect of prolonged radiation exposure during electrophysiological (EP) procedures on direct DNA damage. Comet test has shown to assess DNA damage following radiation exposure. METHODS: We performed a single-center prospective observational study assessing direct DNA damage using the quantitative comet assay in patients undergoing cardiac resynchronization (CRT) and atrial fibrillation (AF) catheter ablation procedures. Venous comet assay was performed pre, immediately post procedure and at 3-month duration in twenty-two (N=22) patients who underwent catheter ablation for symptomatic AF and fourteen (N=14) patients who underwent CRT implantation. RESULTS: The median [interquartile range (IQR)] fluoroscopy time, radiation dose and dose area product (DAP) were 34.3 (27.97 - 45.48) minutes, 853.07 (611.36 - 1334.76) mGy and 16,994.10 (9,023.65 - 58,845.00) UGym2 in the ablation group and 30.05 (18.75 - 37.33) minutes, 345.00 (165.09 - 924.79) mGy and 11,837.20 [7182.67 - 35567.75] UGym2 in the CRT group. When compared with pre-procedure, there was a statistically significant increase in median (IQR) DNA migration on comet assay in the ablation group immediately post procedure [+6.55 µm (0.78, 10.25, p=0.02)] that subsequently decreased at 3 months [-1.00 µm (-2.20, 0.78), p=0.03] but not in the CRT group. CONCLUSION: There was a significant increase in DNA damage as detected by comet assay immediately post procedure that normalized at 3 months in patients undergoing AF ablation. Further large prospective studies are warranted to evaluate the impact of this prolonged radiation exposure and DNA damage on long-term follow up.

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