Zeolites are one of humanity's most important synthetic products. These aluminosilicate-based materials represent a large segment of the global economy. Indeed, the value of zeolites used in petroleum refining as catalysts and in detergents as water softeners is estimated at $350 billion per year.
View Article and Find Full Text PDFRecently, it has been shown that in K(+) solution the human telomeric sequence d[TAGGG(TTAGGG)(3)] forms a (3 + 1) intramolecular G-quadruplex, while the Bombyx mori telomeric sequence d[TAGG(TTAGG)(3)], which differs from the human counterpart only by one G deletion in each repeat, forms a chair-type intramolecular G-quadruplex, indicating an effect of G-tract length on the folding topology of G-quadruplexes. To explore the effect of loop length and sequence on the folding topology of G-quadruplexes, here we examine the structure of the four-repeat Giardia telomeric sequence d[TAGGG(TAGGG)(3)], which differs from the human counterpart only by one T deletion within the non-G linker in each repeat. We show by NMR that this sequence forms two different intramolecular G-quadruplexes in K(+) solution.
View Article and Find Full Text PDFBackground: Anemia is prevalent in patients with heart failure and an independent prognostic sign of poor outcome. The current report is a meta-analysis of published clinical trials assessing the use of erythropoeisis stimulating agents (ESA) in heart failure (HF) patients with anemia.
Methods: Literature and Medline search was performed to identify studies with control groups (case-control, cohort or randomized controlled trials) that examined the effect of ESA therapy in patients with HF and anemia.
Background: A recent nonrandomized interinstitutional study reported that adjuvant mitotane following surgery for adrenocortical carcinoma (ACC) was associated with decreased recurrence. Because of the limitations of this study, we investigated the influences of surgery and adjuvant mitotane in a large series of ACC patients evaluated and treated at a single referral center.
Study Design: Retrospective evaluation of patients followed at a single institution after surgery for ACC.
The quality of DNA affects the accuracy and repeatability of quantitative PCR results. Different DNA extraction and purification methods were compared for quantification of Roundup Ready (RR) soybean (event 40-3-2) by real-time PCR. DNA was extracted using cetylmethylammonium bromide (CTAB), DNeasy Plant Mini Kit, and Wizard Magnetic DNA purification system for food.
View Article and Find Full Text PDFPediatr Dermatol
December 2009
Scabies is a common human parasitic infection in infants and children. But diagnosis pitfalls are frequent in infants, in whom the clinical presentation is usually atypical and different from adults. We report a misleading case of a 5-month-old child, who presented with pruritic brown-red macules of the trunk showing a positive Darier's sign, suggestive of an urticaria pigmentosa.
View Article and Find Full Text PDFShort contiguous arrays of variant CTAGGG repeats in the human telomere are unstable in the male germline and somatic cells, suggesting formation of unusual structures by this repeat type. Here, we report on the structure of an intramolecular G-quadruplex formed by DNA sequences containing four human telomeric variant CTAGGG repeats in potassium solution. Our results reveal a new robust antiparallel G-quadruplex fold involving two G-tetrads sandwiched between a G.
View Article and Find Full Text PDFA number of different processes that impact on telomere length dynamics have been identified but factors that affect the turnover of repeats located proximally within the telomeric DNA are poorly defined. We have identified a particular repeat type (CTAGGG) that is associated with an extraordinarily high mutation rate (20% per gamete) in the male germline. The mutation rate is affected by the length and sequence homogeneity of the (CTAGGG)n array.
View Article and Find Full Text PDFTex Heart Inst J
September 2009
Anemia is prevalent in heart-failure patients, and it has been associated with increased mortality rates. In a retrospective study, we evaluated the effects of anemia on long-term survival in patients who experienced purely diastolic heart failure.Heart-failure patients with preserved systolic function (left ventricular ejection fraction, > or =0.
View Article and Find Full Text PDFA two and a half day meeting on G-quadruplexes was held in Louisville, KY, USA (April 18-21, 2009). A specific goal of this conference was to promote discussion on the biology of G-quadruplexes. In practice this was represented in four main ways, namely in biophysics, bio/nanotechnology, therapeutics, and what might be termed "intrinsic biology".
View Article and Find Full Text PDFFront Neuroendocrinol
October 2009
We reviewed oxytocin (OT), arginine-vasopressin (AVP) and gonadal hormone involvement in various modes of social information processing in mice and rats. Gonadal hormones regulate OT and AVP mediation of social recognition and social learning. Estrogens foster OT-mediated social recognition and the recognition and avoidance of parasitized conspecifics via estrogen receptor (ER) alpha (ERalpha) and ERbeta.
View Article and Find Full Text PDFPatients with persistent chest pain and no obstructive coronary artery disease are often labeled as having noncardiac pain and not offered further cardiologic testing or treatment. Diagnostic uncertainty for persistent chest pain is associated with adverse quality of life, morbidity, and health care costs. Two underdiagnosed cardiac causes for persistent chest pain include microvascular coronary disease and abnormal cardiac nociception.
View Article and Find Full Text PDFPreviously, it has been reported that human telomeric DNA sequences could adopt in different experimental conditions four different intramolecular G-quadruplexes each involving three G-tetrad layers, namely, Na(+) solution antiparallel-stranded basket form, K(+) crystal parallel-stranded propeller form, K(+) solution (3 + 1) Form 1, and K(+) solution (3 + 1) Form 2. Here we present a new intramolecular G-quadruplex adopted by a four-repeat human telomeric sequence in K(+) solution (Form 3). This structure is a basket-type G-quadruplex with only two G-tetrad layers: loops are successively edgewise, diagonal, and edgewise; glycosidic conformations of guanines are syn x syn x anti x anti around each tetrad.
View Article and Find Full Text PDFHeart failure (HF) with preserved ejection fraction (EF) has a high prevalence in the geriatric population, and this cohort may be at risk of complications caused by polypharmacy. Effects of commonly used cardiac medications on long-term survival of patients >80 years with HF and preserved left ventricular EF were assessed. One hundred forty-two patients were evaluated.
View Article and Find Full Text PDFOncology (Williston Park)
December 2008
The diagnosed incidence rate of neuroendocrine tumors (NETs) is on the rise. Prevalence calculations show NETs to be more common then previously thought. Although generally thought to be indolent, advanced NETs remain incurable and are resistant to most cytotoxic agents.
View Article and Find Full Text PDFVery recent studies showed that mammalian telomeres were transcribed into telomeric-repeat-containing RNAs and suggested that these RNA molecules were biologically important. Here we report on a structural study of RNA G-quadruplexes formed by human telomeric RNA sequences in K(+) solution. Our data indicated that these sequences formed propeller-type parallel-stranded RNA G-quadruplexes.
View Article and Find Full Text PDFRecently, the human telomeric d[TAGGG(TTAGGG)(3)] sequence has been shown to form in K(+) solution an intramolecular (3+1) G-quadruplex structure, whose G-tetrad core contains three strands oriented in one direction and the fourth in the opposite direction. Here we present a study on the structure of the Bombyx mori telomeric d[TAGG(TTAGG)(3)] sequence, which differs from the human counterpart only by one G deletion in each repeat. We found that this sequence adopted multiple G-quadruplex structures in K(+) solution.
View Article and Find Full Text PDFContext: von Hippel-Lindau disease is characterized by highly vascularized tumors of multiple organs.
Evidence Acquisition: We present a patient with von Hippel-Lindau disease with multiple renal and pancreatic tumors and a malignant pheochromocytoma infiltrative of the sacrum and associated with lymph nodule metastases. The pheochromocytoma expressed high protein level of vascular endothelial growth factor and platelet-derived growth factor-beta receptor.
Am J Physiol Heart Circ Physiol
December 2008
Clinical and experimental evidence has shown that myocardial ischemia activates cardiac spinal afferents that mediate sympathoexcitatory reflex responses. During myocardial ischemia, thromboxane A2 (TxA2) is released in large quantities by activated platelets in the coronary circulation of patients with coronary artery disease. We hypothesized that endogenous TxA2 contributes to sympathoexcitatory reflexes during myocardial ischemia through stimulation of TxA2/prostaglandin endoperoxide (TP) receptors.
View Article and Find Full Text PDFAnn Dermatol Venereol
October 2008
Background: Lymphomatoid papulosis (LyP) is a rare lymphoproliferative disorder. It is now included in the World Health Organisation (WHO) classification of cutaneous lymphomas. Although frequently described in adults, there have been only a few reported cases of LyP in children; diagnosis is often difficult in this population and no clear guidelines have been established regarding management or monitoring.
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