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1.
Nanomaterials (Basel) ; 13(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37887943

RESUMO

Gas sensing is of significant importance in a wide range of disciplines, including industrial safety and environmental monitoring. In this work, a low-cost SILAR (Successive Ionic Layer Adsorption and Reaction) technique was employed to fabricate pure CuO, Zn-doped CuO, and Na-doped CuO nanotextured films to efficiently detect CO2 gas. The structures, morphologies, chemical composition, and optical properties of all films are characterized using different tools. All films exhibit a crystalline monoclinic phase (tenorite) structure. The average crystallite size of pure CuO was 83.5 nm, whereas the values for CuO/Zn and CuO/Na were 73.15 nm and 63.08 nm, respectively. Subsequently, the gas-sensing capabilities of these films were evaluated for the detection of CO2 in terms of sensor response, selectivity, recovery time, response time, and limits of detection and quantification. The CuO/Na film offered the most pronounced sensitivity towards CO2 gas, as evidenced by a sensor response of 12.8% at room temperature and a low limit of detection (LoD) of 2.36 SCCM. The response of this sensor increased to 64.5% as the operating temperature increased to 150 °C. This study thus revealed a brand-new CuO/Na nanostructured film as a highly effective and economically viable sensor for the detection of CO2.

2.
Sci Rep ; 13(1): 18398, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884608

RESUMO

For the sake of people's health and the safety of the environment, more efforts should be directed towards the fabrication of gas sensors that can operate effectively at room temperature (RT). In this context, increased attention has been paid to developing gas sensors based on rare-earth (RE)-doped transparent conducting oxides (TCO). In this report, lanthanum-doped zinc oxide (La-doped ZnO) films were fabricated by sol-gel and spin-coating techniques. XRD analysis revealed the hexagonal structure of the ZnO films, with preferred growth along the (002) direction. The crystallite size was decreased from 33.21 to 26.41 nm with increasing La content to 4.0 at.%. The UV-vis-NIR indicating that the films are highly transparent (˃ 80%), La-doping increased the UV blocking ability of the films and narrowed the optical band gap (Eg) from 3.275 to 3.125 eV. Additionally, La-doping has influenced the refractive index of the samples. Gas sensing measurements were performed at ambient temperature (30 °C) and a relative humidity (RH) of 30%, employing different flow rates of carbon dioxide (CO2) gas used synthetically with air. Among the evaluated sensors, the ZnO: 4.0 at.% La sensor exhibited the most significant gas response, with a value of 114.22%. This response was observed when the sensor was subjected to a flow rate of 200 SCCM of CO2 gas. Additionally, the sensor revealed a response time of 24.4 s and a recovery time of 44 s. The exceptional performance exhibited by the sensor makes it very appropriate for a wide range of industrial applications. Additionally, we assessed the effect of humidity, selectivity, reusability, repeatability, detection limit, and limit of quantification.

3.
J Clin Med ; 12(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37109267

RESUMO

PURPOSE: To investigate the outcomes of accelerated (A-CXL) and iontophoresis (I-CXL) corneal crosslinking in a large retrospective cohort with progressive keratoconus. METHODS: This retrospective observational cohort study included consecutive patients treated by A-CXL (9 mW/5.4 J/cm2) or I-CXL with a minimal follow-up of 12 months. Visual acuity, manifest refraction, topography, specular microscopy, and corneal optical coherence tomography (OCT) were evaluated at baseline and at the last visit. Progression was defined as an increase in the maximum topographic keratometry (Kmax) of 1D. RESULTS: 302 eyes of 241 patients with a mean age of 25.2 ± 7.5 years were included from 2012 to 2019: 231 and 71 eyes in the A-CXL and I-CXL groups, respectively. The mean follow-up was 27.2 ± 13.2 months (maximum: 85.7 months). Preoperatively, the mean Kmax was 51.8 ± 4.0D, with no differences between groups. Mean topographic measurements and spherical equivalent remained stable during the follow-up. At the last visit, CXL failure was reported in 60 eyes (19.9%): 40 (14.7%) versus 20 (28.2%) in A-CXL versus I-CXL, respectively, p = 0.005. The likelihood of progression after CXL was significantly higher following I-CXL: RR = 1.62, CI95 = [1.02 to 2.59], p = 0.04. Demarcation line presence at 1 month was positively correlated with higher efficacy of CXL, p = 0.03. No endothelial damage was reported, especially in 51 thin corneas (range = 342-399 µm). CONCLUSIONS: A-CXL seems more effective than I-CXL in stabilizing keratoconus; this is to be taken into account when a therapeutic indication is posed according to the aggressiveness of the keratoconus.

4.
Magn Reson Imaging ; 97: 13-23, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36581213

RESUMO

Magnetic Resonance Fingerprinting (MRF) is a new quantitative technique of Magnetic Resonance Imaging (MRI). Conventionally, MRF requires sequential correlation of the acquired MRF signals with all the signals of (a large sized) MRF dictionary. This is a computationally intensive matching process and is a major challenge in MRF image reconstruction. This paper introduces the use of clustering techniques (to reduce the effective size of MRF dictionary) by splitting MRF dictionary into multiple small sized MRF dictionary components called MRF signal groups. The proposed method has been further optimized for parallel processing to reduce the computation time of MRF pattern matching. A multi-core GPU based parallel framework has been developed that enables the MRF algorithm to process multiple MRF signals simultaneously. Experiments have been performed on human head and phantom datasets. The results show that the proposed method accelerates the conventional MRF (MATLAB based) reconstruction time up to 25× with single-core CPU implementation, 300× with multi- core CPU implementation and 1035× with the proposed multi-core GPU based framework by keeping the SNR of the resulting images in a clinically acceptable range. Furthermore, experimental results show that the memory requirements of MRF dictionary get significantly reduced (due to efficient memory utilization) in the proposed method.


Assuntos
Encéfalo , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Algoritmos , Imagens de Fantasmas
5.
Nanomaterials (Basel) ; 12(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35159796

RESUMO

Currently, hydrogen generation via photocatalytic water splitting using semiconductors is regarded as a simple environmental solution to energy challenges. This paper discusses the effects of the doping of noble metals, Ir (3.0 at.%) and Ni (1.5-4.5 at.%), on the structure, morphology, optical properties, and photoelectrochemical performance of sol-gel-produced SnO2 thin films. The incorporation of Ir and Ni influences the position of the peaks and the lattice characteristics of the tetragonal polycrystalline SnO2 films. The films have a homogeneous, compact, and crack-free nanoparticulate morphology. As the doping level is increased, the grain size shrinks, and the films have a high proclivity for forming Sn-OH bonds. The optical bandgap of the un-doped film is 3.5 eV, which fluctuates depending on the doping elements and their ratios to 2.7 eV for the 3.0% Ni-doped SnO2:Ir Photoelectrochemical (PEC) electrode. This electrode produces the highest photocurrent density (Jph = 46.38 mA/cm2) and PEC hydrogen production rate (52.22 mmol h-1cm-2 at -1V), with an Incident-Photon-to-Current Efficiency (IPCE% )of 17.43% at 307 nm. The applied bias photon-to-current efficiency (ABPE) of this electrode is 1.038% at -0.839 V, with an offset of 0.391% at 0 V and 307 nm. These are the highest reported values for SnO2-based PEC catalysts. The electrolyte type influences the Jph values of photoelectrodes in the order Jph(HCl) > Jph(NaOH) > Jph(Na2SO4). After 12 runs of reusability at -1 V, the optimized photoelectrode shows high stability and retains about 94.95% of its initial PEC performance, with a corrosion rate of 5.46 nm/year. This research provides a novel doping technique for the development of a highly active SnO2-based photoelectrocatalyst for solar light-driven hydrogen fuel generation.

6.
Nanomaterials (Basel) ; 11(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34835849

RESUMO

Thin films of ZnO and ZnO/carbon nanotubes (CNTs) are prepared and used as CO2 gas sensors. The spray pyrolysis method was used to prepare both ZnO and ZnO/CNTs films, with CNTs first prepared using the chemical vapor deposition method (CVD). The chemical structure and optical analyses for all the prepared nanomaterials were performed using X-ray diffraction (XRD), Fourier transformer infrared spectroscopy (FTIR), and UV/Vis spectrophotometer devices, respectively. According to the XRD analysis, the crystal sizes of ZnO and ZnO/CNTs were approximately 50.4 and 65.2 nm, respectively. CNTs have average inner and outer diameters of about 3 and 13 nm respectively, according to the transmitted electron microscope (TEM), and a wall thickness of about 5 nm. The detection of CO2 is accomplished by passing varying rates of the gas from 30 to 150 sccm over the prepared thin-film electrodes. At 150 sccm, the sensitivities of ZnO and ZnO/CNTs sensors are 6.8% and 22.4%, respectively. The ZnO/CNTs sensor has a very stable sensitivity to CO2 gas for 21 days. Moreover, this sensor has a high selectivity to CO2 in comparison with other gases, in which the ZnO/CNTs sensor has a higher sensitivity to CO2 compared to H2 and C2H2.

7.
Biomed Opt Express ; 12(7): 4478-4495, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34457427

RESUMO

Laser Doppler holography (LDH) is a full-field blood flow imaging technique able to reveal human retinal and choroidal blood flow with high temporal resolution. We here report on using LDH in the anterior segment of the eye without making changes to the instrument. Blood flow in the bulbar conjunctiva and episclera as well as in corneal neovascularization can be effectively imaged. We additionally demonstrate simultaneous holographic imaging of the anterior and posterior segments by simply adapting the numerical propagation distance to the plane of interest. We used this feature to track the movements of the retina and pupil with high temporal resolution. Finally, we show that the light backscattered by the retina can be used for retro-illumination of the anterior segment. Hence digital holography can reveal opacities caused by absorption or diffusion in the cornea and eye lens.

8.
Orphanet J Rare Dis ; 16(1): 55, 2021 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-33516254

RESUMO

BACKGROUND: Thygeson's superficial punctate keratitis (TSPK) is a rare and still poorly understood disease of the ocular surface, responsible for recurrent episodes of photophobia and eye pain. While TSPK is considered as a benign condition, a subset of patients has frequent recurrences or even chronic disease, two situations in which there are currently no therapeutic guidelines. We used a preexisting Facebook TSPK patient support group to assess the clinical journey and the burden of disease of TSPK. RESULTS: An online survey was sent to the patient support group. The first part of the questionnaire gathered information on demographics and the patient's clinical journey [diagnostic modalities, symptoms, duration and frequency of recurrent episodes (RE), efficacy and tolerance to treatments]. The second part focused on quality of life (QoL) using the Ocular Surface Disease-QoL (OSD-QoL) questionnaire. Seventy-two patients out of 595 members of the support group completed the questionnaire during the 3-months study period. Eighty percent of patients developed symptoms before 30 years old, and 47% reported a delay in the diagnosis above 1 year. Sixty percent of patients reported over 5 RE yearly, and 18% of RE lasted more than 3 months. Forty percent of all patients used cyclosporine eyedrops (50% of those with > 5 episodes/year) and it was perceived as effective by 72% of these patients. The impact on daily life activities was judged as severe by 22% of patients, while 38% reported reduced professional activity and 80% were deeply saddened by their eye condition. CONCLUSION: TSPK patients may present with frequent recurrences and/or chronic disease, that result in a severe impact on QoL, and an off-label use of topical immunomodulatory eye drops, suggesting the urgent need for controlled studies. The utility of using social networks for rare ophthalmic disease research includes, faster data collection, data from patients across the globe, and also raises relevant questions about their real needs.


Assuntos
Ceratite , Qualidade de Vida , Adulto , Efeitos Psicossociais da Doença , Humanos , Doenças Raras/tratamento farmacológico , Rede Social
10.
Am J Hypertens ; 34(1): 30-33, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32840289

RESUMO

BACKGROUND: Malignant hypertension is macrovascular and microvascular endothelial injury responsible for multiple organ damage. Considering the anatomical and functional homologies between the posterior pole of the eye and the kidney, ophthalmological explorations may inform clinicians on the mechanisms underpinning concurrent kidney injury in this condition. More specifically, we investigated whether the wall-to-lumen ratio (WLR) of retinal arterioles measured by adaptive optics ophthalmoscopy could be correlated to WLR of kidney arterioles as determined by pathology. We sought to estimate the incidence of retinal arteriole occlusion a supposedly uncommon complication of malignant hypertension. METHODS: All patients hospitalized in our renal Intensive Care Unit for malignant hypertension between 2016 and 2019 were referred to ophthalmological examinations. RESULTS: Twenty-seven patients were included. Median retinal WLR was 0.39 [0.31-0.47] and was correlated with initial systolic (r = 0.56, P = 0.003) and mean blood pressure (r = 0.46, P = 0.02) upon admission. The retinal WLR was not correlated to renal pathological findings, as assessed by juxtaglomerular WLR (r = 0.38, P = 0.2), ratio of glomerulosclerosis (r = -0.39, P = 0.2), or tubulointerstitial fibrosis (r = -0.45, P = 0.08). Retinal WLR was not associated with neurological or cardiovascular end-organ damage. Branch retinal artery occlusion was detected in 18.5% of patients and exudative retinal detachment (ERD) in 29.6% of patients, without any significant correlation with canonical signs of retinal hypertension including optic disc swelling. CONCLUSIONS: In the setting of malignant hypertension, we failed to demonstrate a significant relationship between WLR and other meaningful end-organ injuries. However, branch retinal artery occlusion and ERD may have been hitherto underestimated.


Assuntos
Arteríolas , Hipertensão Maligna , Sistema Justaglomerular/diagnóstico por imagem , Nefropatias , Oclusão da Artéria Retiniana , Descolamento Retiniano , Arteríolas/diagnóstico por imagem , Arteríolas/patologia , Determinação da Pressão Arterial/métodos , Determinação da Pressão Arterial/estatística & dados numéricos , Correlação de Dados , Feminino , França/epidemiologia , Humanos , Hipertensão Maligna/complicações , Hipertensão Maligna/diagnóstico , Hipertensão Maligna/epidemiologia , Hipertensão Maligna/fisiopatologia , Incidência , Nefropatias/diagnóstico , Nefropatias/epidemiologia , Nefropatias/etiologia , Masculino , Pessoa de Meia-Idade , Oftalmoscopia/métodos , Retina/diagnóstico por imagem , Oclusão da Artéria Retiniana/diagnóstico , Oclusão da Artéria Retiniana/epidemiologia , Oclusão da Artéria Retiniana/etiologia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/epidemiologia , Descolamento Retiniano/etiologia , Vasos Retinianos/patologia , Vasos Retinianos/fisiopatologia
11.
Ocul Surf ; 18(2): 231-236, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31759182

RESUMO

PURPOSE: To determine neurotrophic keratitis (NK) frequency, etiologies and prognostic factors, and evaluate the outcome of its management. METHODS: In this retrospective epidemiologic study, we reviewed the electronic records of all patients consulting our tertiary referral eye hospital between November 2009 and October 2017. NK was defined as corneal hypoesthesia or anesthesia associated with epithelial irregularities. RESULTS: Among the 305,351 patients' files screened for eligibility, 335 (354 eyes) were included, yielding an NK frequency of 11/10,000 (0.11%). Their mean ± SD age was 63.1 ± 21.0 years. Eyes were equally divided among the Mackie classification 3 stages. The most frequent etiology was herpetic eye disease (114 eyes; 32.2%). A multifactorial cause was found for 121 (34.2%) eyes. Surgery required for 118 eyes (33.3%). Respective success rates for amniotic membrane transplantation (AMT) or matrix-regeneration of stages 2 and 3, and autologous serum of stage 1 were 57.2%, 63.6% and 21.7%, with mean healing times of 15.0, 16.3 and 85 days. The overall healing rate was 79.5%, with a mean of 44.8 days to healing. Advanced initial stage, diminished corrected-distance visual acuity (CDVA) and advanced age correlated with worse final CDVA. CONCLUSIONS: NK was more frequent than previously reported in the literature. Delayed diagnoses indicated we must increase ophthalmologists' awareness of this disease for patients with decreased corneal sensitivity and abnormal epithelium. To improve prognosis and final CDVA, NK-specific treatment should be initiated as soon as the diagnosis is suspected. Patient-centered combinations of different therapeutic components and close monitoring achieved promising results.


Assuntos
Distrofias Hereditárias da Córnea , Ceratite Herpética , Doenças do Nervo Trigêmeo , Adulto , Idoso , Idoso de 80 Anos ou mais , Âmnio/transplante , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Genome Biol Evol ; 10(11): 2947-2960, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239696

RESUMO

Understanding the molecular evolutionary basis of social behavior is a major challenge in evolutionary biology. Social insects evolved a complex language of chemical signals to coordinate thousands of individuals. In the fire ant Solenopsis invicta, chemical signals are involved in the determination of a polymorphic social organization. Single-queen (monogyne) or multiqueen (polygyne) social structure is determined by the "social chromosome," a nonrecombining region containing ∼504 genes with two distinct haplotypes, SB and Sb. Monogyne queens are always SBB, while polygyne queens are always SBb. Workers discriminate monogyne from polygyne queens based on olfactory cues. Here, we took an evolutionary genomics approach to search for candidate genes in the social chromosome that could be responsible for this discrimination. We compared the SB and Sb haplotypes and analyzed the evolutionary rates since their divergence. Notably, we identified a cluster of 23 odorant receptors in the nonrecombining region of the social chromosome that stands out in terms of nonsynonymous changes in both haplotypes. The cluster includes twelve genes formed by recent Solenopsis-specific duplications. We found evidence for positive selection on several tree branches and significant differences between the SB and Sb haplotypes of these genes. The most dramatic difference is the complete deletion of two of these genes in Sb. These results suggest that the evolution of polygyne social organization involved adaptations in olfactory genes and opens the way for functional studies of the molecular mechanisms underlying social behavior.


Assuntos
Formigas/genética , Evolução Biológica , Cromossomos de Insetos , Receptores Odorantes/genética , Olfato/genética , Adaptação Biológica , Animais , Masculino , Polimorfismo Genético , Seleção Genética , Comportamento Social
13.
Genome Biol Evol ; 10(9): 2490-2500, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982411

RESUMO

Chemical communication is fundamental for the operation of insect societies. Their diverse vocabulary of chemical signals requires a correspondingly diverse set of chemosensory receptors. Insect olfactory receptors (ORs) are the largest family of chemosensory receptors. The OR family is characterized by frequent expansions of subfamilies, in which duplicated ORs may adapt to detect new signals through positive selection on their amino acid sequence. Ants are an extreme example with ∼400 ORs per genome-the highest number in insects. Presumably, this reflects an increased complexity of chemical communication. Here, we examined gene duplications and positive selection on ant ORs. We reconstructed the hymenopteran OR gene tree, including five ant species, and inferred positive selection along every branch using the branch-site test, a total of 3326 tests. We find more positive selection in branches following species-specific duplications. We identified amino acid sites targeted by positive selection, and mapped them onto a structural model of insect ORs. Seventeen sites were under positive selection in six or more branches, forming two clusters on the extracellular side of the receptor, on either side of a cleft in the structure. This region was previously implicated in ligand activation, suggesting that the concentration of positively selected sites in this region is related to adaptive evolution of ligand binding sites or allosteric transmission of ligand activation. These results provide insights into the specific OR subfamilies and individual residues that facilitated adaptive evolution of olfactory functions, potentially explaining the elaboration of chemical signaling in ant societies.


Assuntos
Formigas/genética , Proteínas de Insetos/genética , Filogenia , Receptores Odorantes/genética , Seleção Genética , Animais , Formigas/química , Sítios de Ligação , Evolução Molecular , Duplicação Gênica , Proteínas de Insetos/química , Ligantes , Modelos Moleculares , Conformação Proteica , Receptores Odorantes/química
14.
Transplantation ; 92(3): 341-5, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21659946

RESUMO

BACKGROUND: Because myeloproliferative disorders (MPDs) are a frequent cause of Budd-Chiari syndrome (BCS), treatment directed toward altering platelet production and function may be more rational and effective than anticoagulation after liver transplantation. METHODS: We reviewed data on 25 patients who received liver transplantation for BCS at our institution from 1987 to 2007. Posttransplant antithrombotic treatment was based on the cause of BCS: 17 patients with MPDs received hydroxyurea/aspirin; 5 received warfarin; and 3 (2 whose hypercoagulable disorder was corrected and 1 with sarcoidosis) received no therapy. RESULTS: Both graft survival (88% at 5 years) and patient survival (92% at 5 years) were superior in the BCS group compared with the 2609 patients who received liver transplants for other indications. Vascular complications included three instances of hepatic artery stenosis (NS compared with non-BCS liver recipients), one of portal vein thrombosis (nonsignificant [NS]), and one of portal vein stenosis (NS). All 25 patients underwent multiple liver biopsies with no bleeding complications. CONCLUSIONS: Using hydroxyurea and aspirin to treat patients with BCS caused by an MPD seems to be safe and effective and avoids the risks of anticoagulation with warfarin.


Assuntos
Síndrome de Budd-Chiari/etiologia , Síndrome de Budd-Chiari/prevenção & controle , Fibrinolíticos/uso terapêutico , Transplante de Fígado/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Adolescente , Adulto , Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Síndrome de Budd-Chiari/mortalidade , Criança , Feminino , Seguimentos , Sobrevivência de Enxerto , Artéria Hepática , Humanos , Hidroxiureia/uso terapêutico , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Veia Porta , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/prevenção & controle , Trombose/etiologia , Trombose/mortalidade , Trombose/prevenção & controle , Varfarina/uso terapêutico , Adulto Jovem
15.
Cancer Genet ; 204(3): 162-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21504716

RESUMO

Distinguishing mantle cell lymphoma (MCL), from low-grade B-cell lymphoma is important because MCL is clinically more aggressive and is treated differently. Though most MCL overexpress cyclinD1 (CCND1) and have a t(11;14)(q13;q32), MCL that are negative for CCND1 exist. Some have translocations involving cyclinD2 (CCND2) and either the immunoglobulin heavy chain or kappa light chain locus. We present a CD5-positive, CCND1-negative B-cell lymphoma with a novel translocation involving CCND2 and the immunoglobulin lambda (IGL) gene. A 64-year-old male underwent resection of a polypoid mass of the ileum. Histology showed atypical, medium-sized lymphoid cells positive for CD20, CD5, CD43, and CCND2 by immunohistochemistry, and negative for CCND1, CCND3, and p27. Fluorescence in situ hybridization was negative for CCND1 abnormalities, but demonstrated a CCND2/IGL fusion. Clinical workup revealed stage IV disease. Current diagnostic criteria are insufficient for subclassifying this case, highlighting the need for additional studies on CCND2-translocated B-cell lymphomas to guide therapy appropriately.


Assuntos
Antígenos CD5/biossíntese , Ciclina D2/genética , Cadeias lambda de Imunoglobulina/genética , Linfoma de Células B/genética , Linfoma de Célula do Manto/genética , Neoplasias da Medula Óssea/diagnóstico , Neoplasias da Medula Óssea/genética , Neoplasias da Medula Óssea/metabolismo , Cromossomos Humanos Par 12 , Cromossomos Humanos Par 22 , Ciclina D1/metabolismo , Diagnóstico Diferencial , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/metabolismo , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Linfoma de Células B/diagnóstico , Linfoma de Células B/metabolismo , Linfoma de Célula do Manto/diagnóstico , Linfoma de Célula do Manto/metabolismo , Masculino , Pessoa de Meia-Idade , Translocação Genética
16.
Am J Dermatopathol ; 31(8): 814-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19786854

RESUMO

Kimura disease (KD) is a rare condition that predominantly affects young middle-aged Asian men. It is classically characterized by tumors in the head and neck region with associated eosinophilia and elevated serum immunoglobulin E levels. The exact pathogenesis of this condition remains unknown. Although some regard it as a reactive condition, others believe that it is a T-cell-mediated disease. T-cell clonality has been recently demonstrated in a few cases. We report a 37-year-old Lebanese woman who had both KD and mycosis fungoides (MF). T-cell receptor gene rearrangement studies using 2 different techniques did not detect any clonality for T-cell receptor in both KD and MF lesions. Due to the presence on histology of lymphoid follicles and the persistent high serum immunoglobulin E levels, we elected to attempt treatment with rituximab. Although the KD lesions persisted, they became softer and less nodular. As for the MF lesions, they flared transiently and then exhibited a sustained improvement over a follow-up period of 1 year.


Assuntos
Hiperplasia Angiolinfoide com Eosinofilia/complicações , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Micose Fungoide/complicações , Neoplasias Cutâneas/complicações , Adulto , Hiperplasia Angiolinfoide com Eosinofilia/tratamento farmacológico , Hiperplasia Angiolinfoide com Eosinofilia/patologia , Anticorpos Monoclonais Murinos , Feminino , Genes de Imunoglobulinas , Genes Codificadores dos Receptores de Linfócitos T , Humanos , Líbano , Micose Fungoide/tratamento farmacológico , Micose Fungoide/patologia , Rituximab , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia
17.
Clin Chem ; 55(4): 823-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19233910

RESUMO

BACKGROUND: Patients differ in responses to warfarin, which is commonly prescribed to treat thromboembolic events. Genetic variations in the cytochrome P450, family 2, subfamily C, polypeptide 9 (CYP2C9), vitamin K epoxide reductase complex, subunit 1 (VKORC1), and gamma-glutamyl carboxylase (GGCX) genes have been shown to contribute to impaired metabolism of warfarin. METHODS: We designed a custom multiplex single-nucleotide polymorphism (SNP) panel to interrogate the CYP2C9 *2, *3, VKORC1 (-1639G-->A), and GGCX (1181T-->G) alleles simultaneously in a single sample by use of single-base extension and capillary electrophoresis after genomic DNA extraction and PCR amplification. RESULTS: Our assay successfully detected various genotypes from known controls and 24 unknown samples. It was found to be 100% concordant with sequencing results. CONCLUSIONS: Our multiplexed SNP panel can be successfully used in genotyping of patient blood samples. Results can be combined with other clinical parameters in an algorithm for warfarin dosing. These data provide a proof-in-principle of multiplexed SNP analysis using rapid single-base extension and capillary electrophoresis, and warrant additional validation using a larger cohort of patient samples.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Carbono-Carbono Ligases/genética , Técnicas Genéticas , Oxigenases de Função Mista/genética , Polimorfismo de Nucleotídeo Único/genética , Varfarina/metabolismo , Hidrocarboneto de Aril Hidroxilases/metabolismo , Carbono-Carbono Ligases/metabolismo , Citocromo P-450 CYP2C9 , Genótipo , Humanos , Oxigenases de Função Mista/metabolismo , Vitamina K Epóxido Redutases
18.
Clin Infect Dis ; 45(3): e25-8, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17599300

RESUMO

Invasive liver abscess syndrome, which is caused by hypervirulent Klebsiella pneumoniae subtypes, has been emerging worldwide over the past 2 decades. The syndrome is associated with the hypermucoviscosity phenotype of K. pneumoniae strains and with the magA and rmpA genes. We provide the first laboratory evidence of the presence of rmpA-positive K. pneumoniae in North America.


Assuntos
Proteínas de Bactérias/genética , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae , Abscesso Hepático/microbiologia , Povo Asiático , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/microbiologia , Amplificação de Genes , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Síndrome , Texas
19.
Liver Transpl ; 13(1): 157-61, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17192857

RESUMO

Graft-versus-host disease (GVHD) after liver transplantation is rare but associated with a very high mortality (over 85%). Most treatments focus on increasing immunosuppression, addition of antibody preparations such as OKT3 and antithymocyte globulin to eliminate the donor lymphocytes, and supporting myelopoiesis by use of cytokines. However, the results are very poor. We reasoned that a better therapeutic approach would be to reduce the immunosuppression and allow the patient's immune system an opportunity to reject the allograft donor T cells. We tested this novel therapeutic approach in 3 patients diagnosed with GVHD. Two patients had rapid loss of donor T cell chimerism and resolution of their symptoms. The other patient continued to progress to severe GVHD and died. The patients who responded to withdrawal of immunosuppression had a later onset of symptoms and a lower level of donor CD3+ T cells at the start of treatment. We conclude that larger studies are needed to further evaluate these results and to determine what factors may affect the likelihood that a patient may respond to this approach.


Assuntos
Colangite Esclerosante/terapia , Doença Enxerto-Hospedeiro/etiologia , Imunossupressores/uso terapêutico , Hepatopatias/terapia , Transplante de Fígado/métodos , Adulto , Biópsia , Complexo CD3/biossíntese , Colangite Esclerosante/cirurgia , Doença Enxerto-Hospedeiro/diagnóstico , Humanos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Pele/patologia , Linfócitos T/metabolismo
20.
Arch Pathol Lab Med ; 130(9): 1339-48, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16948522

RESUMO

CONTEXT: Diagnostic molecular pathology is rapidly becoming an indispensable tool for anatomic pathologists. Familiarity with some of the technologic principles and current, as well as upcoming, molecular diagnostic applications is greatly advantageous for today's practice of pathology. OBJECTIVES: To provide a discussion of the most common techniques currently used in molecular pathology laboratories and review their essential applications to diagnosis and management of neoplastic diseases. DATA SOURCES: A literature review and illustrative cases from the authors' molecular diagnostic practices. CONCLUSIONS: Applications such as clonality assays, molecular cytogenetics, and chimerism analysis are providing us with accurate tools to resolve difficult diagnostic and management decisions in hemato-oncology. This should serve as a future model to expand molecular applications into the wider field of solid tumors.


Assuntos
Diagnóstico , Biologia Molecular/tendências , Patologia/tendências , Coloração Cromossômica , Citogenética/tendências , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Patologia/métodos
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