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[This corrects the article DOI: 10.1155/2020/3646712.].
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Galega officinalis products have been used for the control of diabetes (type 2) across the world. Experimental and clinical evaluations of galegine substance produced by a medicinal plant (Galega officinalis) provided the pharmacological and chemical basis for metformin discovery which was confirmed for diabetes therapy. In this paper, the molecularly imprinted polymer (MIP) was synthesized for galegine, using galegine as a template molecule, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, azobisisobutyronitrile (AIBN) as a reaction initiator, and acetonitrile as a solvent. The assisted functional groups, morphology, topographic image of surface, and crystalline structure of synthesized MIP were characterized by FT-IR spectroscopy, field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) images, and XRD diffraction pattern techniques, respectively. Also, the performance of the mentioned electrode was quantified and qualified by the differential pulse voltammetry technique (DPV). The galegine amount was determined with the polarographic technique. In this research, the galegine extraction conditions were optimized and graphene nanoparticles were used to increase the adsorption. In addition, different parameters affecting extraction were investigated such as MIP adsorbent amount, pH of solution, effect of the surfactant, and ionic compound to achieve high recovery percent. The recovery percent, limit of detection (LOD), limit of quantification (LOQ), and relative standard deviation (RSD %) were 4.101 µg·mL-1, 12.427 µg·mL-1, and 1.199% (n = 3), respectively. The results show that the prepared MIP can be used as an effective and inexpensive adsorbent for preconcentration and galegine extraction from a natural sample. It is noteworthy that this developed method was used successfully to determine galegine extracted from Galega officinalis L.
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A quantum thermodynamic cycle with a chiral multiferroic working substance such as LiCu_{2}O_{2} is presented. Shortcuts to adiabaticity are employed to achieve an efficient, finite-time quantum thermodynamic cycle, which is found to depend on the spin ordering. The emergent electric polarization associated with the chiral spin order, i.e., the magnetoelectric coupling, renders possible steering of the spin order by an external electric field and hence renders possible an electric-field control of the cycle. Due to the intrinsic coupling between the spin and the electric polarization, the cycle performs an electromagnetic work. We determine this work's mean-square fluctuations, the irreversible work, and the output power of the cycle. We observe that the work mean-square fluctuations are increased with the duration of the adiabatic strokes, while the irreversible work and the output power of the cycle show a nonmonotonic behavior. In particular, the irreversible work vanishes at the end of the quantum adiabatic strokes. This fact confirms that the cycle is reversible. Our theoretical findings evidence the existence of a system inherent maximal output power. By implementing a Lindblad master equation we quantify the role of thermal relaxations on the cycle efficiency. We also discuss the role of entanglement encoded in the noncollinear spin order as a resource to affect the quantum thermodynamic cycle.
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Hemoglobin Constant Spring (HbCS) is the most common nondeletional alpha-thalassemia variant causing HbH disease, making its detection crucial in populations at risk. Universal newborn screening for HbH is carried out in California. Identification of alpha-thalassemia genotypes responsible for HbH and HbH-CS requires rapid, accurate and cost-effective genotyping methods suitable for population screening. We incorporated the HbCS mutation into our existing seven-plex genotyping assay for common alpha-thalassemia deletions. To assess the feasibility and diagnostic utility of this expanded multiplex gap-PCR assay, we determined genotypic frequencies of HbCS in samples referred for alpha-thalassemia testing between 1 January 2006 and 31 December 2008. During the 3-year study period, 1436 samples were genotyped for alpha-thalassemia. HbH-CS accounted for 23 (13%) of the 176 cases of HbH disease identified. In a subset of 145 newborns referred by the California NBS program with an elevated Hb Bart's level at birth, HbH disease was confirmed in 134 (93%) and HbH-CS identified in 13 (10%) of these. This expanded genotyping assay has proven to be a rapid, reliable and clinically useful diagnostic tool for the detection of HbH-CS disease.
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Hemoglobinas Anormais/genética , Reação em Cadeia da Polimerase/métodos , Deleção de Sequência/genética , Talassemia alfa/genética , California , Seguimentos , Genótipo , Humanos , Recém-Nascido , Talassemia alfa/sangue , Talassemia alfa/diagnósticoRESUMO
Certain beta globin gene mutations produce a thalassemia major phenotype in the heterozygous state. While most such patients have thalassemia intermedia, we describe a young Guatemalan child with a de novo mutation in the beta globin gene, codon 31 T --> G (Hemoglobin Hakkari), who developed severe anemia at the age of 10 months and remains transfusion-dependent. The substitution of B13 leucine with arginine in the beta globin results in alteration of a critical heme contact point resulting in an extremely unstable variant hemoglobin and a clinical picture that is characterized by ineffective erythropoiesis and numerous intracytoplasmic inclusions within the erythrocyte precursors of the bone marrow. .
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Hemoglobinas Anormais/genética , Mutação Puntual , Globinas beta/genética , Talassemia beta/genética , Guatemala , Humanos , Corpos de Inclusão , Lactente , Masculino , Talassemia beta/patologiaRESUMO
Triphenylphosphine reduction of saturated endoperoxides derived from 6,6-dimethylfulvene and spiro[2.4]hepta-4,6-diene in the presence of nucleophiles results in the formation of products that mainly stem from deoxygenation followed by carbocation formation. Nucleophilic attack by solvent proceeds by an S(N)1 like mechanism; allyl shifts and cyclopropylcarbinyl-cyclobutyl rearrangements also occur. With the systems lacking carbocation-stabilizing groups, the deoxygenation step is preceded by attack of H(2)O at the phosphorus.
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Acetatos/síntese química , Compostos Organofosforados/química , Peróxidos/química , Acetatos/química , Catálise , Estrutura Molecular , OxirreduçãoRESUMO
The hemoglobinopathies represent a genetically heterogeneous group of disorders. Clinically important hemoglobin variants have been increasingly reported in the USA. Consequently, rapid and accurate testing methods are needed to address the growing diagnostic challenges of identifying these variants. To evaluate the utility of the Luminex LabMAP system for hemoglobinopathy testing, we adapted single base primer extension (SBPE) to this platform to detect 11 clinically important hemoglobin variants. Clinical samples from 11 individuals were tested for five beta-globin mutations (C-Harlem, D-Iran, Fannin-Lubbock and Hope) and six alpha-globin mutations (J-Toronto, Hasharon, G-Philadelphia, G-Norfolk, Constant-Spring and Quong-Sze). Two separate multiplexed SBPE assays were developed. Biotinylated amplification products were hybridized to fluorescent microspheres tagged with allele-specific capture probes and analyzed by flow cytometry on the Luminex100 instrument. The median fluorescent intensity (MFI) ranged from 1255 to 7478 fluorescence units (FU) and from 282 to 2609 FU above background for all positive beta-globin and alpha-globin alleles, respectively. Using the highest background MFI + 3 SD as a conservative threshold, MFI values uniformly discriminated wild type from mutant alleles, and genotypes were correctly identified in all samples tested. This pilot study demonstrates the potential application of the Luminex LabMAP genotyping platform to newborn screening for definitive hemoglobinopathy testing.
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Testes Genéticos/métodos , Genótipo , Hemoglobinopatias/diagnóstico , Hemoglobinas Anormais/genética , Citometria de Fluxo/métodos , Globinas/genética , Hemoglobinopatias/sangue , Humanos , Reação em Cadeia da PolimeraseRESUMO
Newborn screening is an accepted public health measure to ensure that appropriate health care is provided in a timely manner to infants with hereditary/metabolic disorders. Alpha-thalassemia is a common hemoglobin (Hb) disorder, and causes Hb H (beta4) disease, and usually fatal homozygous alpha(0)-thalassemia, also known as Hb Bart's (gamma4) hydrops fetalis syndrome. In 1996, the State of California began to investigate the feasibility of universal newborn screening for Hb H disease. Initial screening was done on blood samples obtained by heel pricks from newborns, and stored as dried blood spots on filter paper. Hb Bart's levels were measured as fast-moving Hb by automated high-performance liquid chromatography (HPLC) identical to that currently used in newborn screening for sickle cell disease. Subsequent confirmation of Hb H disease was done by DNA-based diagnostics for alpha-globin genotyping. A criterion of 25% or more Hb Bart's as determined by HPLC detects most, if not all cases of Hb H disease, and few cases of alpha-thalassemia trait. From January, 1998, through June, 2000, 89 newborns were found to have Hb H disease. The overall prevalence for Hb H disease among all newborns in California is approximately 1 per 15,000. Implementation of this program to existing newborn hemoglobinopathy screening in populations with significant proportions of southeast Asians is recommended. The correct diagnosis would allow affected infants to be properly cared for, and would also raise awareness for the prevention of homozygous alpha(0)-thalassemia or Hb Bart's hydrops fetalis syndrome.
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Testes Genéticos , Hemoglobina H/análise , Hemoglobinas Anormais/análise , Triagem Neonatal , Talassemia alfa/epidemiologia , Sudeste Asiático/etnologia , Asiático , California , Cromatografia Líquida de Alta Pressão , Feminino , Frequência do Gene , Genótipo , Globinas/deficiência , Globinas/genética , Hemoglobina H/genética , Hemoglobinas Anormais/genética , Humanos , Hidropisia Fetal/genética , Hidropisia Fetal/prevenção & controle , Recém-Nascido , Masculino , Mutação de Sentido Incorreto , Prevalência , Deleção de Sequência , Talassemia alfa/diagnóstico , Talassemia alfa/etnologia , Talassemia alfa/genéticaRESUMO
BACKGROUND: Molecules that are highly expressed by human prostate cancers may serve as therapeutically relevant targets or tumor markers. Tyrosine kinases are frequently overexpressed in metastatic tumor cells and this prompted us to screen for tyrosine kinases that are overexpressed in prostate cancer cells. METHODS: Expression levels of the EphA2 receptor tyrosine kinase were determined by Western blot analysis in canine and human prostate cancer cell lines and in immortalized and transformed variants of 267B1 prostatic epithelial cells. EphA2 levels in benign human prostate and prostate cancers were also determined in formalin-fixed, paraffin-embedded tissues using immunohistochemical staining. RESULTS: Metastatic prostate cancer cells overexpressed EphA2 by 10-100 fold as compared with non-invasive prostatic epithelial cells. EphA2 immunoreactivity in vivo was also significantly greater in human prostate cancers as compared with benign prostate epithelium. CONCLUSIONS: The EphA2 receptor tyrosine kinase is differentially expressed in human and canine prostate cancer cell lines and overexpressed in human prostate cancers as compared with benign prostate tissues. Metastasis-derived canine prostate carcinoma cell lines overexpress EphA2 and may provide pre-clinical models to further evaluate the role of EphA2 in prostate carcinogenesis. Further investigations are needed to determine the utility of EphA2 as a tumor marker and a novel target in human prostate cancer.
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Carcinoma/enzimologia , Neoplasias da Próstata/enzimologia , Receptores Proteína Tirosina Quinases/biossíntese , Animais , Western Blotting , Cães , Humanos , Imuno-Histoquímica , Masculino , Hiperplasia Prostática/enzimologia , Receptor EphA2 , Células Tumorais Cultivadas , Regulação para CimaRESUMO
EphA2 is a member of the Eph family of receptor tyrosine kinases, which are increasingly understood to play critical roles in disease and development. We report here the regulation of EphA2 by E-cadherin. In nonneoplastic epithelia, EphA2 was tyrosine-phosphorylated and localized to sites of cell-cell contact. These properties required the proper expression and functioning of E-cadherin. In breast cancer cells that lack E-cadherin, the phosphotyrosine content of EphA2 was decreased, and EphA2 was redistributed into membrane ruffles. Expression of E-cadherin in metastatic cells restored a more normal pattern of EphA2 phosphorylation and localization. Activation of EphA2, either by E-cadherin expression or antibody-mediated aggregation, decreased cell-extracellular matrix adhesion and cell growth. Altogether, this demonstrates that EphA2 function is dependent on E-cadherin and suggests that loss of E-cadherin function may alter neoplastic cell growth and adhesion via effects on EphA2.
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Caderinas/fisiologia , Fatores de Transcrição/metabolismo , Neoplasias da Mama , Caderinas/análise , Adesão Celular/fisiologia , Divisão Celular/fisiologia , Efrina-A2 , Células Epiteliais/química , Células Epiteliais/citologia , Células Epiteliais/enzimologia , Humanos , Fosforilação , Fatores de Transcrição/análise , Células Tumorais Cultivadas , Tirosina/metabolismoRESUMO
Expression of mRNAs encoding ten laminin chain variants was studied by reverse transcription-polymerase chain reaction (RT-PCR) of mRNA extracted from cultured mouse blastocysts. alpha1, beta1 and gamma1 mRNAs, of which products form laminin-1, were the only chains expressed in blastocysts before hatching. alpha4 and alpha5 mRNAs were additionally expressed after attachment of blastocysts to culture dishes. alpha2 and beta2 mRNAs started to be expressed at the stage of allantois formation. Among ten laminin chains, only the mRNA encoding components of laminin-5 (alpha3, beta3 and gamma2) was missing in embryos up to the stage of allantois formation.
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Various diester analogues of nifedipine in which the ortho nitrophenyl group at position 4 is replaced by 1-methyl-2-methylsulfonyl-5-imidazolyl substituent, were synthesized and evaluated as calcium channel antagonists on guinea-pig ileal smooth muscle. Nifedipine was used as a standard. Compound 6n was found to be the most active.
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Bloqueadores dos Canais de Cálcio/síntese química , Ácidos Nicotínicos/síntese química , Nifedipino/análogos & derivados , Nifedipino/síntese química , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Cobaias , Íleo/efeitos dos fármacos , Íleo/metabolismo , Técnicas In Vitro , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Ácidos Nicotínicos/farmacologia , Nifedipino/farmacologiaRESUMO
The past theoretical contributions in Doppler ultrasonic imaging have borrowed heavily from the electromagnetic case. In these contributions, most points of departure between the ultrasonic and electromagnetic cases were taken care of by heuristic incorporation of factors in the derived formulas. A theory is presented that is more complete in the sense that it specifically accounts for the diffracted fields of the transducer aperture (assumed to be a source of a Gaussian focussed beam), the interaction of these fields with the scattering sites, and the interaction of the transducer aperture with the back scattered fields. The theoretical formulation was used to perform a series of computer simulation studies on Doppler ultrasound. The control afforded by the theory over different parameters of the system has allowed us to study the effect of the different signal bandwidths, tissue attenuation constants, and the role of transducer design in the ultrasound Doppler systems.
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Ultrassonografia/instrumentação , Sangue , Matemática , Modelos Teóricos , Transdutores , UltrassomRESUMO
In this paper, we have first presented a new computational procedure for the calculation of the "true" forward scattered fields of a multicomponent object. By "true" we mean fields that are not limited by the first-order approximations, such as those used in the first-order Born and Rytov calculations. Although the results shown will only include the second-order fields for a multicomponent object, the computational procedure can easily be generalized for higher order scattering effects. Using this procedure we have shown by computer simulation that even when each component of a two-component object is weakly scattering, the multiple scattering effects become important when the components are blocking each other. We have further shown that when strongly scattering components that are large compared to a wavelength are not blocking each other, the scattering effects can be ignored. Both these conclusions agree with intuitive reasoning. Since all the currently available diffraction tomography algorithms are based on the assumption that the object satisfies the first-order scattering assumption, it is interesting to test them under conditions when this assumption is violated. We have used the scattered fields obtained with the new computational procedure to test these algorithms, and shown the resulting artifacts. Our main conclusion drawn from this computer simulation study is that even when object inhomogeneities are as small as 5 percent of the background, multiple scattering can introduce severe distortions in multicomponent objects.
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The authors describe 7 cases of rupture of the Valsalva sinus. Until rupture the aneurysm is silent. Aortic insufficiency and left to right shunt are major components of this syndrome. Surgical treatment under extra-corporal circulation needs aortotomy and an approach of the ruptured extremity to close the defect and maintaining the integrity of the valvular structures.
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Valva Aórtica , Aneurisma Cardíaco/complicações , Adolescente , Adulto , Feminino , Aneurisma Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Ruptura EspontâneaRESUMO
The authors report personal experience of surgical treatment of 47 aneurysms of the thoracic aorta, showing that the symptoms, the etiology, the treatment and the prognosis are variable depending on the site of the aneurysm. One may note regression of syphilis as a cause and an increase in the number of degenerative and traumatic aneurysms. In aneurysms of the ascending aorta, total replacement of the ascending aorta with reimplantation of the coronary arteries, according to a simplified technic, seems to give the best immediate and long term results.