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1.
Braz. j. biol ; 83: e249911, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339366

RESUMO

Abstract Hematological and hematopoietic cells malignancies of the genes and hematopoietic cells are associated with the genetic mutation, often at the chromosomal level. The standard cytogenetic study is widely accepted as one of the main diagnostics and prognostic determinants in patients. Therefore, the current descriptive and cross-sectional study sought to determine the cytogenetic analysis of frequent hematological malignancies in Pakistan. A total of 202 peripheral bone marrow or blood samples from patients with benign and malignant hematological malignancy were taken using a conventional G-banding technique. Among enrolled patients, the mean age was 21.5 years ± 23.4, and gender-wise distribution showed a marked predominance of the male 147 (73%) population compared to the female 55 (27%). Patients in the age group (2-10 years) had the highest frequency, 48 (24%), of hematological neoplasms, followed by age (11-20 years) with 40 (20%). Normal karyotypes (46, XX/46, XY) was found in 51% (n=103) patients. Furthermore, the frequency of complex karyotype was 30 (15%), while normal was seen in 171 (85%) patients. Pre-B Acute Lymphoblastic Leukemia (Pre-B ALL) was the most prevalent malignancy of 66 (33%), followed by Chronic Myelogenous Leukemia (CML) of 41 (20%) and Acute Lymphocytic Leukemia of 29 (14%). Translocation was the most prevalent 50 (25%), followed by hypotriploidy 14 (7%) and monosomy 8 (4%) on chromosome aberration analysis. In addition, t(9:22) translocation was found to be 20 (10%) in CML, with the majority in the age group (31-40 years). This study recommends that karyotyping should be tested frequently in hematological conditions because it may provide insight into the relative chromosomal changes associated with particular malignancies.


Resumo As neoplasias hematológicas e de células hematopoiéticas dos genes e as células hematopoiéticas estão associadas à mutação genética, geralmente em nível cromossômico. O estudo citogenético padrão é amplamente aceito como um dos principais determinantes diagnósticos e prognósticos em pacientes. Portanto, o presente estudo descritivo e transversal buscou determinar a análise citogenética de neoplasias hematológicas frequentes no Paquistão. Um total de 202 amostras de medula óssea periférica ou sangue de pacientes com malignidade hematológica benigna e maligna foi coletado usando uma técnica convencional de banda G. Entre os pacientes inscritos, a média de idade foi de 21,5 anos ± 23,4, e a distribuição por gênero mostrou uma marcada predominância da população masculina de 147 (73%) em comparação com a feminina de 55 (27%). Pacientes na faixa etária (2-10 anos) tiveram a maior frequência, 48 (24%), de neoplasias hematológicas, seguida da idade (11-20 anos) com 40 (20%). Cariótipos normais (46, XX / 46, XY) foram encontrados em 51% (n = 103) dos pacientes. Além disso, a frequência de cariótipo complexo foi de 30 (15%), enquanto normal foi observada em 171 (85%) pacientes. Leucemia linfoblástica aguda pré-B (LLA Pré-B) foi a doença maligna mais prevalente de 66 (33%), seguida por leucemia mieloide crônica (LMC) de 41 (20%) e leucemia linfocítica aguda de 29 (14%). A translocação foi o 50 mais prevalente (25%), seguido por hipotriploidia 14 (7%) e monossomia 8 (4%) na análise de aberração cromossômica. Além disso, a translocação t (9:22) encontrada foi de 20 (10%) na LMC, com a maioria na faixa etária (31-40 anos). Este estudo recomenda que o cariótipo deve ser testado com frequência em condições hematológicas porque pode fornecer informações sobre as alterações cromossômicas relativas associadas a doenças malignas específicas.

2.
Braz. j. biol ; 82: e239991, 2022. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1278503

RESUMO

Abstract High resistance to antimicrobials is associated with biofilm formation responsible for infectious microbes to withstand severe conditions. Therefore, new alternatives are necessary as biofilm inhibitors to control infections. In this study, the antimicrobial and antibiofilm activities of Fagonia indica extracts were evaluated against MDR clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica has antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against multidrug resistant (MDR) clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica had antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against MDR isolates. The maximum inhibitory effects of Fagonia indica chloroform extract on biofilm formation was observed on Staphylococcus aureus (71.84%) followed by Klebsiella pneumoniae (70.83%) after 48 hrs showing that inhibition is also time dependent. Our results about bacterial cell protein leakage indicated that MDR isolates treated with chloroform extract of Fagonia indica showed maximum protein leakage of K. pneumoniae (59.14 µg mL-1) followed by S. aureus (56.7 µg mL-1). Cell attachment assays indicated that chloroform extract resulted in a 43.5-53.5% inhibition of cell adherence to a polystyrene surface. Our results revealed that extracts of Fagonia indica significantly inhibited biofilm formation among MDR clinical isolates, therefore, could be applied as antimicrobial agents and cost effective biofilm inhibitor against these MDR isolates.


Resumo A alta resistência aos antimicrobianos está associada à formação de biofilme responsável por micróbios infecciosos para suportar condições severas. Portanto, novas alternativas são necessárias como inibidores de biofilme para controlar infecções. Neste estudo, as atividades antimicrobiana e antibiofilme dos extratos de Fagonia indica foram avaliadas contra isolados clínicos MDR. O extrato exibiu seu efeito antibiofilme ao alterar a aderência e a desintegração da parede celular bacteriana. Fagonia indica tem efeito antibacteriano com valores de concentração inibitória mínima (CIM) variando de 125 a 500 µg mL-1, e valor de concentração bactericida mínima (MBC) de 500-3000 µg mL-1 contra isolados clínicos multirresistentes (MDR). O extrato exibiu seu efeito antibiofilme ao alterar a aderência e a desintegração da parede celular bacteriana. Fagonia indica teve efeito antibacteriano com valores de concentração inibitória mínima (CIM) variando de 125 a 500 µg mL-1, e concentração bactericida mínima (MBC) de 500-3000 µg mL-1 contra isolados MDR. Os efeitos inibitórios máximos do extrato de clorofórmio Fagonia indica na formação de biofilme foi observada em Staphylococcus aureus (71,84%), seguido por Klebsiella pneumoniae (70,83%) após 48 horas, mostrando que a inibição também é dependente do tempo. Nossos resultados sobre extravasamento de proteínas de células bacterianas indicaram que isolados MDR tratados com extrato clorofórmico de Fagonia indica apresentaram vazamento máximo de proteínas de K. pneumoniae (59,14 µg mL-1), seguido por S. aureus (56,7 µg mL-1). Ensaios de fixação de células indicaram que o extrato de clorofórmio resultou em uma inibição de 43,5-53,5% da aderência das células a uma superfície de poliestireno. Nossos resultados revelaram que extratos de Fagonia indica inibiram significativamente a formação de biofilme entre isolados clínicos MDR, portanto, poderiam ser aplicados como agentes antimicrobianos e inibidores de biofilme de baixo custo contra esses isolados MDR.

3.
Braz J Biol ; 83: e249911, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669802

RESUMO

Hematological and hematopoietic cells malignancies of the genes and hematopoietic cells are associated with the genetic mutation, often at the chromosomal level. The standard cytogenetic study is widely accepted as one of the main diagnostics and prognostic determinants in patients. Therefore, the current descriptive and cross-sectional study sought to determine the cytogenetic analysis of frequent hematological malignancies in Pakistan. A total of 202 peripheral bone marrow or blood samples from patients with benign and malignant hematological malignancy were taken using a conventional G-banding technique. Among enrolled patients, the mean age was 21.5 years ± 23.4, and gender-wise distribution showed a marked predominance of the male 147 (73%) population compared to the female 55 (27%). Patients in the age group (2-10 years) had the highest frequency, 48 (24%), of hematological neoplasms, followed by age (11-20 years) with 40 (20%). Normal karyotypes (46, XX/46, XY) was found in 51% (n=103) patients. Furthermore, the frequency of complex karyotype was 30 (15%), while normal was seen in 171 (85%) patients. Pre-B Acute Lymphoblastic Leukemia (Pre-B ALL) was the most prevalent malignancy of 66 (33%), followed by Chronic Myelogenous Leukemia (CML) of 41 (20%) and Acute Lymphocytic Leukemia of 29 (14%). Translocation was the most prevalent 50 (25%), followed by hypotriploidy 14 (7%) and monosomy 8 (4%) on chromosome aberration analysis. In addition, t(9:22) translocation was found to be 20 (10%) in CML, with the majority in the age group (31-40 years). This study recommends that karyotyping should be tested frequently in hematological conditions because it may provide insight into the relative chromosomal changes associated with particular malignancies.


Assuntos
Aberrações Cromossômicas , Neoplasias Hematológicas , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/genética , Humanos , Cariotipagem , Masculino , Paquistão/epidemiologia , Adulto Jovem
4.
Braz J Biol ; 82: e239991, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34190801

RESUMO

High resistance to antimicrobials is associated with biofilm formation responsible for infectious microbes to withstand severe conditions. Therefore, new alternatives are necessary as biofilm inhibitors to control infections. In this study, the antimicrobial and antibiofilm activities of Fagonia indica extracts were evaluated against MDR clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica has antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against multidrug resistant (MDR) clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica had antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against MDR isolates. The maximum inhibitory effects of Fagonia indica chloroform extract on biofilm formation was observed on Staphylococcus aureus (71.84%) followed by Klebsiella pneumoniae (70.83%) after 48 hrs showing that inhibition is also time dependent. Our results about bacterial cell protein leakage indicated that MDR isolates treated with chloroform extract of Fagonia indica showed maximum protein leakage of K. pneumoniae (59.14 µg mL-1) followed by S. aureus (56.7 µg mL-1). Cell attachment assays indicated that chloroform extract resulted in a 43.5-53.5% inhibition of cell adherence to a polystyrene surface. Our results revealed that extracts of Fagonia indica significantly inhibited biofilm formation among MDR clinical isolates, therefore, could be applied as antimicrobial agents and cost effective biofilm inhibitor against these MDR isolates.


Assuntos
Extratos Vegetais , Staphylococcus aureus , Bactérias , Biofilmes , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
6.
J Appl Microbiol ; 130(5): 1721-1729, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32966644

RESUMO

AIMS: This study was designed to analyse the prevalence of class 1 and class 2 integron integrase genes among antibiotic-resistant coliform bacteria isolated from paper currency circulating in Pakistan. METHODS AND RESULTS: A total of 500 individual currency notes were collected from different food vending sites at Lahore, Pakistan. Bacterial population were identified by biochemical and PCR techniques. Antimicrobial susceptibility testing was performed by disc diffusion assay. The highest bacterial population on currency was found from street vendors and butcher shops. Escherichia coli was found to be the most prevalent coliform bacteria followed by Klebsiella sp. and Enterobacter sp. PCR amplification of antimicrobial resistance gene showed the presence of ampC, blaTEM , blaNDM-1 , qnrA, tet(A) and tet(B) genes among coliform isolates. A total of 47 integron integrase bearing strains of coliform bacteria were analysed. Sequence analysis showed the presence of dfrA1-aadA1, dfrA1, dfrA5, dfrA7, aadA1, aadA4 cassette arrays in class 1 integron and dfrA1-sat2-aadA1 in class 2 integrase genes. CONCLUSION: Circulating currency was heavily contaminated with antimicrobial-resistant coliform bacteria bearing class 1 and class 2 integron integrase genes. SIGNIFICANCE AND IMPACT OF THE STUDY: This study describes a potential threat of severe bacterial infections due to improper hand hygiene and community sanitation when dealing with the currency notes.


Assuntos
Farmacorresistência Bacteriana , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Integrases/genética , Integrons/genética , Papel , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Comércio , DNA Bacteriano , Enterobacteriaceae/efeitos dos fármacos , Higiene , Testes de Sensibilidade Microbiana , Paquistão , Reação em Cadeia da Polimerase
7.
ACS Nano ; 12(4): 3551-3556, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29641896

RESUMO

Commercial III-Nitride LEDs and lasers spanning visible and ultraviolet wavelengths are based on epitaxial films. Alternatively, nanowire-based III-Nitride optoelectronics offer the advantage of strain compliance and high crystalline quality growth on a variety of inexpensive substrates. However, nanowire LEDs exhibit an inherent property distribution, resulting in uneven current spreading through macroscopic devices that consist of millions of individual nanowire diodes connected in parallel. Despite being electrically connected, only a small fraction of nanowires, sometimes <1%, contribute to the electroluminescence (EL). Here, we show that a population of electrical shorts exists in the devices, consisting of a subset of low-resistance nanowires that pass a large portion of the total current in the ensemble devices. Burn-in electronic conditioning is performed by applying a short-term overload voltage; the nanoshorts experience very high current density, sufficient to render them open circuits, thereby forcing a new current path through more nanowire LEDs in an ensemble device. Current-voltage measurements of individual nanowires are acquired using conductive atomic force microscopy to observe the removal of nanoshorts using burn-in. In macroscopic devices, this results in a 33× increase in peak EL and reduced leakage current. Burn-in conditioning of nanowire ensembles therefore provides a straightforward method to mitigate nonuniformities inherent to nanowire devices.

8.
Microsc Microanal ; 24(2): 93-98, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29699596

RESUMO

The ability to characterize recombination and carrier trapping processes in group-III nitride-based nanowires is vital to further improvements in their overall efficiencies. While advances in scanning transmission electron microscope (STEM)-based cathodoluminescence (CL) have offered some insight into nanowire behavior, inconsistencies in nanowire emission along with CL detector limitations have resulted in the incomplete understanding in nanowire emission processes. Here, two nanowire heterostructures were explored with STEM-CL: a polarization-graded AlGaN nanowire light-emitting diode (LED) with a GaN quantum disk and a polarization-graded AlGaN nanowire with three different InGaN quantum disks. Most nanowires explored in this study did not emit. For the wires that did emit in both structures, they exhibited asymmetrical emission consistent with the polarization-induced electric fields in the barrier regions of the nano-LEDs. In the AlGaN/InGaN sample, two of the quantum disks exhibited no emission potentially due to the three-dimensional landscape of the sample or due to limitations in the CL detection.

9.
Nanoscale ; 8(15): 8024-32, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27019949

RESUMO

By quantum confining GaN at monolayer thickness with AlN barriers inside of a nanowire, deep ultraviolet LEDs are demonstrated. Full three-dimensional strain dependent energy band simulations are carried out within multiple quantum disk (MQD) GaN/AlN nanowire superlattice heterostructures. It is found that, even within the same nanowire MQD, the emission energy of the ultrathin GaN QDs varies from disk to disk due to the changing strain distribution and polarization charge induced energy band bending along the axial nanowire direction. MQD heterostructures are grown by plasma-assisted molecular beam epitaxy to form self-assembled catalyst-free nanowires with 1 to 2 monolayer thick GaN insertions within an AlN matrix. Photoluminescence peaks are observed at 295 nm and 283 nm from the 2 ML and 1 ML thick MQD samples, respectively. Polarization-doped nanowire LEDs are grown incorporating 1 ML thick GaN MQD active regions from which we observe deep ultraviolet electroluminescence. The shortest LED wavelength peak observed is 240 nm and attributed to electron hole recombination within 1 ML thick GaN QDs.

10.
Small ; 11(40): 5402-8, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26307552

RESUMO

Bottom-up nanowires are attractive for realizing semiconductor devices with extreme heterostructures because strain relaxation through the nanowire sidewalls allows the combination of highly lattice mismatched materials without creating dislocations. The resulting nanowires are used to fabricate light-emitting diodes (LEDs), lasers, solar cells, and sensors. However, expensive single crystalline substrates are commonly used as substrates for nanowire heterostructures as well as for epitaxial devices, which limits the manufacturability of nanowire devices. Here, nanowire LEDs directly grown and electrically integrated on metal are demonstrated. Optical and structural measurements reveal high-quality, vertically aligned GaN nanowires on molybdenum and titanium films. Transmission electron microscopy confirms the composition variation in the polarization-graded AlGaN nanowire LEDs. Blue to green electroluminescence is observed from InGaN quantum well active regions, while GaN active regions exhibit ultraviolet emission. These results demonstrate a pathway for large-scale fabrication of solid state lighting and optoelectronics on metal foils or sheets.

11.
Nano Lett ; 15(1): 332-8, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25487601

RESUMO

InGaN nanowires are suitable building blocks for many future optoelectronic devices. We show that a linear grading of the indium content along the nanowire axis from GaN to InN introduces an internal electric field evoking a photocurrent. Consistent with quantitative band structure simulations we observe a sign change in the measured photocurrent as a function of photon flux. This negative differential photocurrent opens the path to a new type of nanowire-based photodetector. We demonstrate that the photocurrent response of the nanowires is as fast as 1.5 ps.

12.
Nanotechnology ; 25(45): 455201, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25327762

RESUMO

In this report, we demonstrate band gap tuning of the active region emission wavelength from 365 nm to 250 nm in light emitting diodes fashioned from catalyst-free III-nitride nanowires. Optical characteristics of the nanowire heterostructures and fabricated devices are studied via electroluminescence (EL) and photoluminescence spectroscopy over a wide range of active region compositions. It is observed that for typical nanowire plasma assisted molecular beam epitaxy growth conditions, tuning of emission to wavelengths shorter than 300 nm is hampered by the presence of an optically active defect level. We show that by increasing the AlGaN nanowire growth temperatures this defect emission can be suppressed. These findings are applied to growth of the active region of a nanowire light emitting diode, resulting in a polarization-induced nanowire light emitting diode with peak EL at 250 nm.

13.
Annu Rev Biomed Eng ; 16: 455-81, 2014 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-25014789

RESUMO

Magnetic fields have the potential to noninvasively direct and focus therapy to disease targets. External magnets can apply forces on drug-coated magnetic nanoparticles, or on living cells that contain particles, and can be used to manipulate them in vivo. Significant progress has been made in developing and testing safe and therapeutic magnetic constructs that can be manipulated by magnetic fields. However, we do not yet have the magnet systems that can then direct those constructs to the right places, in vivo, over human patient distances. We do not yet know where to put the external magnets, how to shape them, or when to turn them on and off to direct particles or magnetized cells-in blood, through tissue, and across barriers-to disease locations. In this article, we consider ear and eye disease targets. Ear and eye targets are too deep and complex to be targeted by a single external magnet, but they are shallow enough that a combination of magnets may be able to direct therapy to them. We focus on how magnetic fields should be shaped (in space and time) to direct magnetic constructs to ear and eye targets.


Assuntos
Orelha/patologia , Olho/patologia , Campos Magnéticos , Fenômenos Fisiológicos Oculares , Animais , Cegueira/terapia , Complicações do Diabetes , Sistemas de Liberação de Medicamentos , Orelha Interna/patologia , Orelha Média/patologia , Fenômenos Eletromagnéticos , Endoftalmite/terapia , Desenho de Equipamento , Humanos , Degeneração Macular/terapia , Magnetismo , Doenças Retinianas/terapia , Retinite Pigmentosa/terapia
14.
ScientificWorldJournal ; 2014: 974104, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24707223

RESUMO

INTRODUCTION: Use of lead acid battery (LAB) in Bangladesh has risen with sharp rise of motor vehicles. As result, manufacture of LAB is increasing. Most of the lead used by these industries comes from recycling of LAB. Workers in LAB industry are at risk of exposure lead and thus development of lead toxicity. OBJECTIVE: The objective of this study was to measure the blood lead concentration and to assess the magnitude of health problems attributable to lead toxicity among the LAB manufacturing workers. METHODS: A cross-sectional study was conducted among the workers of LAB manufacturing industries located in Dhaka city. RESULT: Mean blood lead level (BLL) among the workers was found to be high. They were found to be suffering from a number of illnesses attributable to lead toxicity. The common illnesses were frequent headache, numbness of the limbs, colic pain, nausea, tremor, and lead line on the gum. High BLL was also found to be related to hypertension and anemia of the workers. CONCLUSION: High BLL and illnesses attributable to lead toxicity were prevalent amongst workers of the LAB manufacturing industries, and this requires attention especially in terms of occupational hygiene and safety.


Assuntos
Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/epidemiologia , Chumbo/sangue , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Adolescente , Adulto , Bangladesh/epidemiologia , Estudos Transversais , Fontes de Energia Elétrica , Índices de Eritrócitos , Humanos , Pessoa de Meia-Idade , Vigilância em Saúde Pública , Fatores de Risco , Adulto Jovem
15.
Nano Lett ; 13(7): 3029-35, 2013 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-23756087

RESUMO

Polarization-induced nanowire light emitting diodes (PINLEDs) are fabricated by grading the Al composition along the c-direction of AlGaN nanowires grown on Si substrates by plasma-assisted molecular beam epitaxy (PAMBE). Polarization-induced charge develops with a sign that depends on the direction of the Al composition gradient with respect to the [0001] direction. By grading from GaN to AlN then back to GaN, a polarization-induced p-n junction is formed. The orientation of the p-type and n-type sections depends on the material polarity of the nanowire (i.e., Ga-face or N-face). Ga-face material results in an n-type base and a p-type top, while N-face results in the opposite. The present work examines the polarity of catalyst-free nanowires using multiple methods: scanning transmission electron microscopy (STEM), selective etching, conductive atomic force microscopy (C-AFM), and electroluminescence (EL) spectroscopy. Selective etching and STEM measurements taken in annular bright field (ABF) mode demonstrate that the preferred orientation for catalyst-free nanowires grown by PAMBE is N-face, with roughly 10% showing Ga-face orientation. C-AFM and EL spectroscopy allow electrical and optical differentiation of the material polarity in PINLEDs since the forward bias direction depends on the p-n junction orientation and therefore on nanowire polarity. Specifically, C-AFM reveals that the direction of forward bias for individual nanowire LEDs changes with the polarity, as expected, due to reversal of the sign of the polarization-induced charge. Electroluminescence measurements of mixed polarity PINLEDs wired in parallel show ambipolar emission due to the mixture of p-n and n-p oriented PINLEDs. These results show that, if catalyst-free III-nitride nanowires are to be used to form polarization-doped heterostructures, then it is imperative to understand their mixed polarity and to design devices using these nanowires accordingly.

16.
Tex Heart Inst J ; 39(2): 258-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22740747

RESUMO

Adenocarcinoma of the parotid gland metastatic to the right ventricle has rarely been reported in the medical literature. We describe the case of a 51-year-old man who had a right ventricular adenocarcinoma that metastasized from his right parotid gland. He had undergone incomplete resection of the parotid tumor, followed by radiotherapy, 5 years earlier. After resecting the cardiac adenocarcinoma with tumor-free margins, we reconstructed the ventricular septum and right ventricle, then performed coronary artery bypass grafting. At the patient's most recent follow-up examination 6 months later, he continued to do well and had a good quality of life.


Assuntos
Adenocarcinoma/secundário , Neoplasias Cardíacas/secundário , Neoplasias Parotídeas/patologia , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Ponte de Artéria Coronária , Neoplasias Cardíacas/cirurgia , Ventrículos do Coração/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/radioterapia , Neoplasias Parotídeas/cirurgia , Procedimentos Cirúrgicos Reconstrutivos , Resultado do Tratamento , Septo Interventricular/patologia
17.
J Magn Magn Mater ; 324(5): 742-754, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23335834

RESUMO

Optimization methods are presented to design Halbach arrays to maximize the forces applied on magnetic nanoparticles at deep tissue locations. In magnetic drug targeting, where magnets are used to focus therapeutic nanoparticles to disease locations, the sharp fall off of magnetic fields and forces with distances from magnets has limited the depth of targeting. Creating stronger forces at depth by optimally designed Halbach arrays would allow treatment of a wider class of patients, e.g. patients with deeper tumors. The presented optimization methods are based on semi-definite quadratic programming, yield provably globally optimal Halbach designs in 2 and 3-dimensions, for maximal pull or push magnetic forces (stronger pull forces can collect nano-particles against blood forces in deeper vessels; push forces can be used to inject particles into precise locations, e.g. into the inner ear). These Halbach designs, here tested in simulations of Maxwell's equations, significantly outperform benchmark magnets of the same size and strength. For example, a 3-dimensional 36 element 2000 cm(3) volume optimal Halbach design yields a ×5 greater force at a 10 cm depth compared to a uniformly magnetized magnet of the same size and strength. The designed arrays should be feasible to construct, as they have a similar strength (≤ 1 Tesla), size (≤ 2000 cm(3)), and number of elements (≤ 36) as previously demonstrated arrays, and retain good performance for reasonable manufacturing errors (element magnetization direction errors ≤ 5°), thus yielding practical designs to improve magnetic drug targeting treatment depths.

18.
Bangladesh Med Res Counc Bull ; 36(1): 1-3, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21280550

RESUMO

This cross-sectional study was carried out in some selected arsenic contaminated rural areas of Bangladesh to determine any clinical changes in oral cavity, among the arsenic exposed population through drinking water. Total 600 respondents (200 arsenicosis patients, 200 non-patients but having the history of taking arsenic contaminated water and another 200 arsenic non-exposed). 75.5% of arsenicosis patients had swelled vallate papillae whereas only 44.5% and 8.5% in case of arsenic exposure and non-exposure subjects respectively. The differences were found statistically significant (p < 0.001). This study suggests that there is a tendency of developing swelled vallate papillae among the arsenic exposed population.


Assuntos
Intoxicação por Arsênico/patologia , Arsênio/farmacologia , Língua/patologia , Adulto , Humanos , Pessoa de Meia-Idade , Língua/efeitos dos fármacos , Abastecimento de Água , Adulto Jovem
19.
Bangladesh Med Res Counc Bull ; 36(1): 23-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21280555

RESUMO

This cross-sectional study was carried out to assess and compare Ankle Brachial Systolic Pressure Index (ABSPI) amongst 120 arsenic exposed and 120 non-exposed populations of Samta village in Bangladesh. Abnormal ABSPI was more prevalent in arsenic exposed (13.3%) than in non-exposed (2.5%) group. The prevalence of abnormal ABSPI for respondents when adjusted for age, sex, BMI, blood pressure status and diabetic status, the prevalence remain significantly different. The findings suggest that those exposed to arsenic have increased chance of having abnormal ABSP and hence increased chance of peripheral arterial disease in Bangladesh.


Assuntos
Índice Tornozelo-Braço , Arsênio/efeitos adversos , Abastecimento de Água/análise , Adulto , Arsênio/análise , Intoxicação por Arsênico/etiologia , Intoxicação por Arsênico/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sístole
20.
Postgrad Med ; 121(3): 131-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19491551

RESUMO

Cardiac papillary fibroelastomas (PFEs) are the most common tumors of the cardiac valves and the third most common cardiac tumor. They are usually detected accidentally on echocardiography, but have the potential to manifest with catastrophic embolic phenomena, resulting in stroke and myocardial infarction. Echocardiography is currently the preferred diagnostic modality, while magnetic resonance imaging and computed tomography are helpful in the differential diagnosis of cardiac tumors. The management of PFEs is empiric, as no large randomized trials have been conducted to support specific treatment guidelines. The treatment of choice for PFEs with high-risk features for peripheral embolization is surgical resection. Anticoagulation is recommended in patients who are poor surgical candidates or who refuse surgery, although its duration and intensity are debatable. This review summarizes current knowledge on the epidemiology, pathology, pathophysiology, clinical manifestations, diagnosis, and treatment of PFEs. It also highlights the need for large randomized clinical trials that would delineate more specific guidelines for managing PFEs with anticoagulation.


Assuntos
Fibroelastose Endocárdica , Neoplasias Cardíacas , Papiloma , Procedimentos Cirúrgicos Cardíacos/métodos , Diagnóstico Diferencial , Ecocardiografia/métodos , Embolização Terapêutica/métodos , Fibroelastose Endocárdica/diagnóstico , Fibroelastose Endocárdica/epidemiologia , Fibroelastose Endocárdica/terapia , Feminino , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/epidemiologia , Neoplasias Cardíacas/terapia , Humanos , Incidência , Imageamento por Ressonância Magnética/métodos , Papiloma/diagnóstico , Papiloma/epidemiologia , Papiloma/terapia , Guias de Prática Clínica como Assunto , Prognóstico , Tomografia Computadorizada por Raios X/métodos
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