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https://www.readbyqxmd.com/read/30107623/acute-administration-of-tibolone-prevents-oxidative-stress-in-ovariectomized-rats-fed-high-fat-and-fructose-diet
#1
Norma Angélica Estrada Cruz, Julio César Almanza Pérez, Ángeles Fortis Barrera, Juan Manuel Gallardo, Leticia Manuel Apolinar, Julia Jeanett Segura Uribe, Sandra Orozco Suárez, Angélica Coyoy Salgado, Christian Guerra Araiza
In addition to oxidative stress due to the increase of free radicals, estrogen deficiency is associated with changes in enzymatic activity, glutathione redox ratio (GSH/GSSG), and the content of oxidative markers such as malondialdehyde. Tibolone, a synthetic steroid, has been used as an elective treatment for the relief of menopausal symptoms. However, the acute effects of hormonal therapy with tibolone on metabolic parameters and oxidative stress markers associated with the first stages of estrogen deficiency are still unknown...
August 14, 2018: Experimental and Clinical Endocrinology & Diabetes
https://www.readbyqxmd.com/read/30107333/enhanced-photocatalytic-activity-of-cds-sns-2-nanocomposite-with-highly-efficient-charge-transfer-and-visible-light-utilization-for-selective-reduction-of-4-nitroaniline
#2
Lei Zhang, Cheng-Gang Niu, Xiao-Ju Wen, Hai Guo, Xiu-Fei Zhao, Chao Liang, Guang-Ming Zeng
Photocatalytic reduction can be an effective and promising technology for the selective reduction of aromatic nitro organics. In this paper, a novel Z-scheme CdS/SnS2 photocatalyst was well-designed and fabricated via simple in-site reaction process containing thioacetamide as a sulfur sources and cubic CdSnO3 as template. The resulting CdS/SnS2 composite has well-constructed cubic nanostructure of strong adhesion between CdS and SnS2 , presenting high absorption to visible light. Importantly, strong charge transfer between the contacting regions of CdS and SnS2 through the intermediate sulfur atoms combined with both metals was generated, which speeds up separation of photogenerated electron and hole...
August 9, 2018: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/30107097/beyond-friedel-and-crafts-directed-alkylation-of-c-h-bonds-in-arenes
#3
Gwilherm Evano, Cédric Theunissen
The alkylation of arenes is one of the most fundamental transformations in chemical synthesis leading to privileged scaffolds in many areas of science. Classical methods for the introduction of alkyl groups to arenes are mostly based on the Friedel-Crafts reaction, radical additions, metallation or pre-functionalization of the arene: these methods however suffer from limitations in scope, efficiency and selectivity. Moreover, they are based on the innate reactivity of the starting arene, favoring the alkylation at a certain position and rendering the introduction of alkyl chains at other positions much more challenging...
August 14, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/30107077/beyond-friedel-and-crafts-innate-alkylation-of-c-h-bonds-in-arenes
#4
Gwilherm Evano, Cédric Theunissen
Alkylated arenes are ubiquitous molecules and building blocks commonly utilized in most areas of science where there is a need for small organic molecules. Despite its apparent simplicity, the regioselective alkylation of arenes is still a challenging transformation in a lot of cases. Classical methods for the introduction of alkyl groups on arenes, which include the venerable Friedel-Crafts reaction, radical additions, metallation or pre-functionalization of the arene, as well as alternatives such as the directed alkylation of C-H bonds, still suffer from severe limitations in terms of scope, efficiency and selectivity...
August 14, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/30107051/gold-nanoparticles-for-enhanced-ionization-and-fragmentation-of-biomolecules-using-ldi-ms
#5
Cody D Sacks, Katherine A Stumpo
New applications for gold nanoparticles (AuNPs) in Laser Desorption Ionization Mass Spectrometry (LDI-MS) are presented here. This work expands on previous biomolecule studies and introduces carbohydrates, steroids, bile acids, and other small molecules as a focus. Broad trends in ionization are observed and specifically of interest are new species that have not previously been reported from AuNPs (e.g., [M+Au]+ ). Interesting fragmentation effects have been observed for diphenhydramine, including similarity to Electron Impact mass spectra and possible radical driven reactions, providing insight into the mechanism of ionization when using AuNPs...
August 14, 2018: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/30106980/optimization-of-total-phenolic-content-from-terminalia-chebula-retz-fruits-using-response-surface-methodology-and-evaluation-of-their-antioxidant-activities
#6
Zunlai Sheng, Jiahong Zhao, Ishfaq Muhammad, Ying Zhang
Ultrasonic-assisted extraction (UAE), using aqueous ethanol as the solvent, was firstly applied to extract phenolic compounds from Terminalia chebula Retz. fruits (T. chebula fruits). In this study, ethanol concentration (%), ultrasonic intensity (W/cm2), particle diameter (mm), extraction temperature (°C), ultrasonic time (min), liquid-solid ratio (mL/g) and extraction cycle were investigated by single-factor experiment and then optimized using a Box-Behnken design. The optimized result for UAE was 68% ethanol concentration, ultrasonic intensity of 3...
2018: PloS One
https://www.readbyqxmd.com/read/30106608/progression-to-chronic-kidney-disease-in-patients-undergoing-nephrectomy-for-small-renal-masses-a-price-to-pay-for-a-therapeutic-success
#7
Tomasz Charytoniuk, Maciej Małyszko, Jan Bączek, Piotr Fiedorczyk, Karolina Siedlaczek, Jolanta Małyszko
Nephrectomy, which constitutes a gold-standard procedure for the treatment of renal-cell carcinoma (RCC), has been widely discussed in the past decade as a significant risk factor of the development of chronic kidney disease (CKD). RCC is the third most common genitourinary cancer in the United States, with an estimated more than 65,000 new cases and 14,970 deaths. The aim of this review was to precisely and comprehensively summarize the status of current knowledge in chronic kidney disease risk factors after nephrectomy, the advantages of minimally invasive vs...
August 14, 2018: Postgraduate Medicine
https://www.readbyqxmd.com/read/30106603/curative-effect-of-digestive-tract-reconstruction-after-radical-gastrectomy-for-distal-gastric-cancer
#8
Ting Li, Xiang-Ling Meng
OBJECTIVE: Short-term complications and long-term prognoses of three kinds of digestive tract reconstructions after radical gastrectomy for distal gastric cancer were compared. MATERIALS AND METHODS: Patients who underwent radical gastrectomy for distal gastric cancer were divided into three groups according to the type of digestive tract reconstruction: Billroth I, Billroth II, and Roux-en-Y anastomosis. Clinicopathological characteristics, intraoperative conditions, short-term complications, and long-term prognoses were compared among the three groups...
August 14, 2018: Journal of Laparoendoscopic & Advanced Surgical Techniques. Part A
https://www.readbyqxmd.com/read/30106574/qm-mm-study-of-tungsten-dependent-benzoyl-coenzyme-a-reductase-rationalization-of-regioselectivity-and-predication-of-w-vs-mo-selectivity
#9
Hui-Xia Qian, Rong-Zhen Liao
The class II benzoyl-coenzyme A reductase (BCR) is a tungsten-dependent enzyme that catalyzes the Birch reduction of benzoyl-CoA to a cyclic diene. The reaction mechanism and regioselectivity of benzoyl-CoA were explored through QM/MM calculations using two different QM regions (124 atoms and 223 atoms) on the solvated enzyme. The reduction reaction involves two major chemical steps that both proceed in the triplet state or in the broken-symmetry singlet state. First, the tungsten-bound water molecule delivers a proton to the C4 of the benzoyl-CoA substrate, coupled with an electron transfer from the WIV center to the substrate...
August 14, 2018: Inorganic Chemistry
https://www.readbyqxmd.com/read/30106572/off-to-the-races-comparison-of-excited-state-dynamics-in-vitamin-b-12-derivatives-hydroxocobalamin-and-aquocobalamin
#10
Theodore E Wiley, Nicholas A Miller, William R Miller, Danielle L Sofferman, Piotr Lodowski, Megan J Toda, Maria Jaworska, Pawel M Kozlowski, Roseanne J Sension
Ultrafast time-resolved spectroscopy was used to study the photochemistry of hydroxocobalamin (HOCbl) and aquocobalamin (H2 OCbl+ ) in solution. Spectroscopic measurements and TD-DFT simulations provide a consistent picture of the spectroscopy and photochemistry. Excitation of H2 OCbl+ results in formation of an excited state followed by rapid internal conversion to the ground state (0.35 ± 0.15 ps) through an S1 /S0 seam at a slightly elongated Co-O bond length and a significantly elongated Co-NIm bond length...
August 14, 2018: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/30106298/substrate-controlled-generation-of-3-sulfonylated-1-indenones-and-3-arylated-z-indenes-via-cu-catalyzed-radical-cyclization-cascades-of-o-alkynylbenzonitriles
#11
Xiao-Tong Zhu, Qiu-Li Lu, Xiang Wang, TIan-Shu Zhang, Wen-Juan Hao, Shu-Jiang Tu, Bo Jiang
Substrate-controlled generation of 3-sulfonylated 1-indenones and 3-arylated ( Z)-indenes through radical cyclization cascades of o-alkynylbenzonitriles with sulfonyl hydrazides was established by combining copper(II) with tert-butyl hydroperoxide (TBHP) as catalytic oxidative system. With installation of the aryl group (R1 ) into the alkynyl unit, sulfonyl radicals triggered addition-cyclization cascades to access 3-sulfonylated 1-indenones with good yields by using Cu/TBHP system, whereas a series of new functionalized 3-arylated ( Z)-indenes were obtained in good yields when o-alkynylbenzonitriles bearing the alkyl group in the alkynyl unit were subjected with arylsulfonyl hydrazides with electron-rich nature under the above conditions...
August 14, 2018: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/30106278/hybrid-of-resveratrol-and-glucosamine-an-approach-to-enhance-antioxidant-effect-against-dna-oxidation
#12
Liang-Liang Bao, Zai-Qun Liu
Resveratrol exhibits various pharmacological activities, which are dependent upon phenolic hydroxyl groups. In this work, glucosamine, lipoic acid, or adamantanamine moiety was applied for attaching to ortho-position of hydroxyl group in resorcinol moiety of resveratrol (known as position-2). Antioxidant effects of the obtained hybrids were characterized using DNA oxidative systems mediated by • OH, Cu2+ /glutathione (GSH), and 2,2'-azobis(2-amidinopropanehydrochloride) (AAPH), respectively. The glucosyl-appended imine and amine at position-2 of resveratrol were found to show higher inhibitory effects than other resveratrol derivatives against AAPH-induced DNA oxidation...
August 14, 2018: Chemical Research in Toxicology
https://www.readbyqxmd.com/read/30106229/melatonin-supplementation-during-prolonged-in-vitro-maturation-improves-the-quality-and-development-of-poor-quality-porcine-oocytes-via-anti-oxidative-and-anti-apoptotic-effects
#13
Tao Lin, Jae Eun Lee, Jeong Won Kang, Reza K Oqani, Eun Seok Cho, Seong Bok Kim, Dong Il Jin
Poor-quality oocytes (those with 1 to 2 layers of cumulus cells) typically possess low meiotic competence and development. Prolonging the duration of in vitro maturation (IVM; 52 h) can enhance the maturation rate of poor-quality oocytes, but it does not improve subsequent embryonic development. This likely reflects the increased reactive oxygen species (ROS) production and apoptosis seen in these oocytes compared with the non-prolonged IVM (44 h) group. Melatonin is a free radical scavenger, anti-oxidant and anti-apoptotic agent that reported to enhance the quality of embryos by inhibiting ROS generation and apoptosis...
August 14, 2018: Molecular Reproduction and Development
https://www.readbyqxmd.com/read/30106074/effect-of-nanosilver-surfaces-on-peptide-reactivity-towards-reactive-oxygen-species
#14
Erik Jacques, Manuel Ahumada, Brianna Rector, Goonay Yousefalizadeh, Constanza Galaz-Araya, Rodrigo Recabarren, Kevin Stamplecoskie, Horacio Poblete, Emilio I Alarcon
The interaction of a terminal tryptophan residue within collagen mimetic peptides when tethered to nanometric silver surfaces was studied using a combination of steady state spectroscopy, ultrafast spectroscopy, and molecular dynamics experiments. Our findings indicate that the effective interaction between the tryptophan and the metal surface occurs in short-time scales (ps) and it is responsible for improving the colloidal stability of the nanoparticles exposed to free radicals. The extent and efficiency of the interaction depends on factors beyond the peptide length that include conformation and distance from the terminal tryptophan to the metal surface...
August 14, 2018: Nanoscale
https://www.readbyqxmd.com/read/30106026/comparative-study-of-laparoscopic-radical-gastrectomy-and-open-radical-gastrectomy
#15
Jie Jiao, Shaozhuang Liu, Cheng Chen, A Maimaiti, Qingsi He, Sanyuan Hu, Wenbin Yu
Introduction: At present, the main treatment of gastric cancer is surgical resection combined with radiotherapy and chemotherapy, the most important part of which is radical gastrectomy. Laparoscopic radical gastrectomy for advanced gastric cancer is difficult to operate, and whether it can achieve the same curative effect with the laparotomy is still controversial. Materials and Methods: This study retrospectively analysed the clinical data of 269 gastric cancer patients surgically treated by our medical team from May 2011 to December 2015 for comparative analysis of the clinical efficacy of laparoscopic-assisted radical gastrectomy and traditional open radical gastrectomy...
August 7, 2018: Journal of Minimal Access Surgery
https://www.readbyqxmd.com/read/30105917/adaptor-protein-p66shc-a-link-between-cytosolic-and-mitochondrial-dysfunction-in-the-development-of-diabetic-retinopathy
#16
Manish Mishra, Arul J Duraisamy, Sudarshan Bhattacharjee, Renu Kowluru
AIMS: Diabetes increases oxidative stress in the retina, and dysfunctions their mitochondria, accelerating capillary cell apoptosis. A 66kDa adaptor protein, p66Shc, is considered as a sensor of oxidative stress-induced apoptosis. In the pathogenesis of diabetic retinopathy, a progressive disease, ROS production by activation of a small molecular weight G-protein (Rac1)-Nox2 signaling precedes mitochondrial damage. Rac1 activation is facilitated by guanine exchange factors (GEFs), and p66Shc increases Rac1-specific GEF activity of Son of Sevenless (Sos1)...
August 14, 2018: Antioxidants & Redox Signaling
https://www.readbyqxmd.com/read/30105868/a-tethered-tolane-twist-the-excited-state
#17
Yuri Kozhemyakin, Maximilian Krämer, Frank Rominger, Andreas Dreuw, Uwe Heiko Bunz
We report the synthesis of a doubly bridged tolane. The target is obtained in a five-step synthesis, starting from commercially available 2-amino-meta-xylene by a combination of Sandmeyer reactions, radical bromination and Stille-type coupling, followed by double ring closing. The doubly tethered tolane is crystalline and shows both in solution and in the solid state a highly twisted conformation. Optical spectroscopy and quantum chemical calculations show that doubly bridged 7 is twisted not only in the ground state but also in the excited state, leading to emission from this state in solution and in the solid state, with strong phosphorescence at cryogenic temperatures...
August 13, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/30105863/effect-of-miconazole-nitrate-on-immunological-response-and-its-preventive-efficacy-in-labeo-rohita-fingerlings-against-oomycetes-saprolegnia-parasitica
#18
Mukta Singh, Ratan Kumar Saha, Himadri Saha, Janmejay Parhi
This study evaluated the effect of sublethal doses of antifungal drug miconazole nitrate (MCZ) on immunological responses and its role as a prophylactic drug against S. parasitica in Labeo rohita fingerlings. Fish were fed with sublethal doses of MCZ, that is, T1-6.30 mgMCZ kgBW-1 , T2-12.61 mgMCZ kgBW-1 and T3-25.22 mgMCZ kgBW-1 , and sampling was done at different time intervals for 240 hr. Immunological parameters viz. lysozyme activity, oxygen radical production and plasma antiprotease activity showed significant enhancement (p < 0...
August 13, 2018: Journal of Fish Diseases
https://www.readbyqxmd.com/read/30105858/lymphedema-in-patients-with-hidradenitis-suppurativa-a-systematic-review-of-published-literature
#19
Robert Micieli, Afsaneh Alavi
BACKGROUND: Lymphedema is a debilitating complication of hidradenitis suppurativa (HS) that can be therapeutically challenging. Systematic evaluation of the clinical presentation and management of this condition has yet to be performed. METHODS: OVID MEDLINE and EMBASE databases were searched along with a review of the references of searched articles for all English reports discussing lymphedema secondary to HS. RESULTS: Two case series and 15 case reports met inclusion criteria, representing 27 patients...
August 13, 2018: International Journal of Dermatology
https://www.readbyqxmd.com/read/30105638/incidental-gallbladder-cancer-how-residual-disease-affects-outcome-in-two-referral-hpb-centers-from-south-america
#20
Luis Gil, Xabier de Aretxabala, Javier Lendoire, Fernando Duek, Juan Hepp, Oscar Imventarza
BACKGROUND: Residual disease (RD) has been described as one of the most relevant prognostic factors after radical surgical resection for incidental gallbladder cancer (IGC). The purpose of the present study was to analyze patterns of RD and determinant prognostic factors in patients undergoing re-resection for IGC. METHODS: Patients undergoing re-exploration due to IGC between 1990 and 2014 were identified in two referral centers from different South-American countries...
August 13, 2018: World Journal of Surgery
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