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https://www.readbyqxmd.com/read/28817272/cysteine-isocyanide-in-multicomponent-reaction-synthesis-of-peptido-mimetic-1-3-azoles
#1
Thimmalapura M Vishwanatha, Katarzyna Kurpiewska, Justyna Kalinowska-Tłuścik, Alexander Dömling
An alternative approach towards the simple and robust synthesis of highly substituted peptidic thiazole derivatives by using Ugi-multicomponent reaction (U-MCR) is described. Thus, we introduced the enantiopure (R)-2-methyl-2-isocyano-3-(tritylthio)propanoate as novel class of isocyanide in MCR. This bifunctional isocyanide was found to undergo mild cyclodehydration to afford thiazole containing peptidomimetics in a short synthetic sequence. Several examples of bis-heterocyclic rings were also synthesized through the proper choice of the aldehyde component in the U-4CR...
August 17, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28798285/is-the-aims-65-score-useful-in-prepdicting-clinical-outcomes-in-korean-patients-with-variceal-and-nonvariceal-upper-gastrointestinal-bleeding
#2
Jung Wan Choe, Seung Young Kim, Jong Jin Hyun, Sung Woo Jung, Young Kul Jung, Ja Seol Koo, Hyung Joon Yim, Sang Woo Lee
Background/Aims: Various clinical scoring systems, including the Glasgow-Blatchford score (GBS), Rockall risk score (RS), and AIMS65 score (AIMS65), have been validated to predict the clinical outcomes in patients with upper gastrointestinal bleeding (UGIB). We compared the performance of these three scoring systems in predicting clinical outcomes in patients with UGIB in Korea. Methods: We retrospectively evaluated 286 patients with UGIB who visited emergency department...
August 14, 2017: Gut and Liver
https://www.readbyqxmd.com/read/28790233/functional-dyspepsia-with-helicobacter-pylori-infection
#3
Rabbinu Rangga Pribadi, Ari Fahrial Syam, Ening Krisnuhoni
Helicobacter pylori infection is commonly found worldwide. In Indonesia, the prevalence of H. pylori infection is 22.1%. The bacteria are responsible for gastritis, peptic ulcer disease (PUD), and gastric cancer.Helicobacter pylori may also has a role in functional dyspepsia. Diagnostic approach consists of noninvasive and invasive examinations. One of the invasive strategy is upper gastrointestinal (UGI) endoscopy and gastric mucosa biopsy.
April 2017: Acta Medica Indonesiana
https://www.readbyqxmd.com/read/28780855/direct-surface-and-droplet-microsampling-for-electrospray-ionization-mass-spectrometry-analysis-with-an-integrated-dual-probe-microfluidic-chip
#4
Cong-Min Huang, Ying Zhu, Di-Qiong Jin, Ryan T Kelly, Qun Fang
Ambient mass spectrometry (MS) has revolutionized the way of MS analysis and broadened its application in various fields. This paper describes the use of microfluidic techniques to simplify the setup and improve the functions of ambient MS by integrating the sampling probe, electrospray emitter probe, and online mixer on a single glass microchip. Two types of sampling probes, including a parallel-channel probe and a U-shaped channel probe, were designed for dry-spot and liquid-phase droplet samples, respectively...
August 15, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28776354/multidisciplinary-approach-to-refractory-upper-gastrointestinal-bleeding-case-series-of-angiographic-embolization
#5
Ko Eun Lee, Ki Nam Shim, Chung Hyun Tae, Min Sun Ryu, Sun Young Choi, Chang Mo Moon, Seong Eun Kim, Hey Kyung Jung, Sung Ae Jung
Although medical and endoscopic hemostasis is now considered as the first-line therapy for nonvariceal upper gastrointestinal (UGI) bleeding, refractory bleeding still occurs in 5%-10% of the patients. In these patients, transcatheter arterial embolization (TAE) or surgery is required, but research on embolization for unmanageable UGI bleeding in Korea is scanty. We reviewed the medical records of 518 patients who underwent endoscopic hemostasis during 4 years. Among these subjects, 8 patients who required embolization due to failure of endoscopic hemostasis were enrolled...
September 2017: Journal of Korean Medical Science
https://www.readbyqxmd.com/read/28775673/the-image-data-resource-a-bioimage-data-integration-and-publication-platform
#6
Eleanor Williams, Josh Moore, Simon W Li, Gabriella Rustici, Aleksandra Tarkowska, Anatole Chessel, Simone Leo, Bálint Antal, Richard K Ferguson, Ugis Sarkans, Alvis Brazma, Rafael E Carazo Salas, Jason R Swedlow
Access to primary research data is vital for the advancement of science. To extend the data types supported by community repositories, we built a prototype Image Data Resource (IDR) that collects and integrates imaging data acquired across many different imaging modalities. IDR links data from several imaging modalities, including high-content screening, super-resolution and time-lapse microscopy, digital pathology, public genetic or chemical databases, and cell and tissue phenotypes expressed using controlled ontologies...
August 2017: Nature Methods
https://www.readbyqxmd.com/read/28768749/orientation-of-native-versus-translocated-juvenile-lesser-spotted-eagles-clanga-pomarina-on-the-first-autumn-migration
#7
Bernd-U Meyburg, Ugis Bergmanis, Torsten Langgemach, Kai Graszynski, Arno Hinz, Ingo Börner, Christiane Meyburg, Wouter M G Vansteelant
The ontogeny of migration routines used by wild birds remains unresolved. Here we investigated the migratory orientation of juvenile lesser spotted eagles (LSE; Clanga pomarina) based on translocation and satellite tracking. Between 2004 and 2016, 85 second-hatched juveniles (Abels) were reared in captivity for release into the declining German population, including 50 birds that were translocated 940 km from Latvia. In 2009, we tracked 12 translocated juveniles, as well as eight native juveniles and nine native adults, to determine how inexperienced birds come to use strategic migration routes...
August 1, 2017: Journal of Experimental Biology
https://www.readbyqxmd.com/read/28761690/duodenal-biopsies-for-the-diagnosis-of-coeliac-disease-are-we-adhering-to-current-guidance
#8
Nilofer Husnoo, Wafaa Ahmed, Muhammad Hanif Shiwani
BACKGROUND: The British Society of Gastroenterology guidelines recommend taking at least four duodenal biopsy specimens at the time of upper gastrointestinal (UGI) endoscopy if coeliac disease (CD) is suspected and it has been shown to increase the diagnostic yield of CD. We assessed the compliance to these guidelines within our institution. We then applied measures to improve our compliance rate and assessed the resulting impact on our diagnostic rate of CD. METHODS: We performed a retrospective audit of electronic records for all patients, with no prior diagnosis of CD, who underwent UGI endoscopy with duodenal biopsies between August 2014 and May 2015...
2017: BMJ Open Gastroenterology
https://www.readbyqxmd.com/read/28759143/facile-synthesis-of-in-chain-multicomponent-functionalized-polymers-via-living-anionic-copolymerization-through-the-ugi-four-component-reaction-ugi-4cr
#9
Heyu Shen, Hongwei Ma, Pibo Liu, Wei Huang, Li Han, Chao Li, Yang Li
By combining living anionic polymerization and the highly efficient Ugi four-component reaction (Ugi-4CR), in-chain, multicomponent, functionalized polymers are facilely synthesized with efficient conversation and abundant functionality. l-[4-[N,N-Bis(trimethylsilyl)-amino]phenyl]-l-phenylethylene, which is redefined as Ugi-DPE, is anionically copolymerized to synthesize the well-defined in-chain, multi-amino functionalized polystyrene (P(St/DPE-NH2 )), the backbone for the Ugi-4CR, via hydrolysis of the copolymerization (P(St/Ugi-DPE))...
July 31, 2017: Macromolecular Rapid Communications
https://www.readbyqxmd.com/read/28752138/is-duodenal-biopsy-appropriate-in-areas-endemic-for-helicobacter-pylori
#10
Abdurrahman Sahin, Gulcin Cihangiroglu, Yilmaz Bilgic, Turan Calhan, Mustafa Cengiz
OBJECTIVE: The primary reason for obtaining duodenal biopsy sample is to diagnose celiac disease. Helicobacter pylori (H. pylori) and drug injury are common causes of duodenitis. The aim of this retrospective study was to explore effects of H. pylori and drugs on duodenal mucosa. METHODS: Duodenal biopsy samples of patients who underwent upper gastrointestinal endoscopy (UGIE) between February 2014 and December 2014 were retrospectively examined. Clinical symptoms, referral indications, endoscopic findings, H...
2017: Northern Clinics of Istanbul
https://www.readbyqxmd.com/read/28741925/an-efficient-one-pot-synthesis-of-densely-functionalized-fused-quinolines-via-sequential-ugi4cc-and-acid-mediated-povarov-type-reaction
#11
Anirban Ghoshal, Doddapaneni Yugandhar, Jagadeesh Babu Nanubolu, Ajay Kumar Srivastava
A divergent synthesis of fused-quinolines has been explored by performing Ugi four-component condensation and sulfuric acid promoted deprotection/Povarov-type reaction in one-pot. The process involves Ugi condensation of propiolic acids, aldehydes/ketones, aminoaldehyde acetals and isocyanides followed by sulfuric acid promoted deprotection and Povarov-type reaction with anilines in ethanol. This method enables straightforward access to the structurally diverse 2,3-dihydro-1H-pyrrolo[3,4-b]quinolin-1-ones (DHPQ), 3,4-dihydrobenzo[b][1,6]naphthyridin-1(2H)-ones (DHBN) and 2,3,4,5-tetrahydro-1H-azepino[4,3-b]quinolin-1-ones (THAQ), starting from readily available starting materials...
July 25, 2017: ACS Combinatorial Science
https://www.readbyqxmd.com/read/28741888/old-dog-new-tricks-in-the-antibiotic-toolbox-%C3%AF-lactam-synthesis-through-diodomethane-addition-onto-amide-dianions
#12
Laurent El Kaim, Alaa Zidan, Julian Garrec, Marie Cordier, Ali Khalil Ali, Abeer El-Naggar, Nour Eldein Abdel-Sattar, Mohamed Ali Hassan
We propose a novel route for the quick and easy synthesis of a broad range of -lactams. The synthesis involves a [3+1] cyclization of amide dianions with diiodomethane. In opposition to the seminal work of Hirai et al, the reaction proved to be a general and efficient approach towards azetidinones. The easiness of the process was confirmed by DFT calculations and its power demonstrated by a diversity oriented synthesis of -lactams with 4 point of diversity brought by the choice of Ugi adducts as starting materials...
July 25, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28728898/kbe009-an-antimalarial-bestatin-like-inhibitor-of-the-plasmodium-falciparum-m1-aminopeptidase-discovered-in-an-ugi-multicomponent-reaction-derived-peptidomimetic-library
#13
Jorge González-Bacerio, Sarah El Chamy Maluf, Yanira Méndez, Isel Pascual, Isabelle Florent, Pollyana M S Melo, Alexandre Budu, Juliana C Ferreira, Ernesto Moreno, Adriana K Carmona, Daniel G Rivera, Maday Alonso Del Rivero, Marcos L Gazarini
Malaria is a global human parasitic disease mainly caused by the protozoon Plasmodium falciparum. Increased parasite resistance to current drugs determines the relevance of finding new treatments against new targets. A novel target is the M1 alanyl-aminopeptidase from P. falciparum (PfA-M1), which is essential for parasite development in human erythrocytes and is inhibited by the pseudo-peptide bestatin. In this work, we used a combinatorial multicomponent approach to produce a library of peptidomimetics and screened it for the inhibition of recombinant PfA-M1 (rPfA-M1) and the in vitro growth of P...
July 4, 2017: Bioorganic & Medicinal Chemistry
https://www.readbyqxmd.com/read/28717373/diagnostic-value-of-alarm-symptoms-for-upper-gi-malignancy-in-patients-referred-to-gi-clinic-a-7-years-cross-sectional-study
#14
Mohammad Hasan Emami, Masoud Ataie-Khorasgani, Nasim Jafari-Pozve
BACKGROUND: Early upper gastrointestinal (UGI) cancer detection had led to organ-preserving endoscopic therapy. Endoscopy is a suitable method of early diagnosis of UGI malignancies. In Iran, exclusion of malignancy is the most important indication for endoscopy. This study is designed to see whether using alarm symptoms can predict the risk of cancer in patients. MATERIALS AND METHODS: A total of 3414 patients referred to a tertiary gastrointestinal (GI) clinic in Isfahan, Iran, from 2009 to 2016 with dyspepsia, gastroesophageal reflux disease (GERD), and alarm symptoms, such as weight loss, dysphagia, GI bleeding, vomiting, positive familial history for cancer, and anorexia...
2017: Journal of Research in Medical Sciences: the Official Journal of Isfahan University of Medical Sciences
https://www.readbyqxmd.com/read/28707691/with-unprotected-amino-acids-to-tetrazolo-peptidomimetics
#15
Rudrakshula Madhavachary, Qian Wang, Alexander Dömling
Here we describe the direct usage of C,N-unprotected amino acids in Ugi-tetrazole reactions to produce a novel class of acid-tetrazole compounds. Surprisingly, only the tetrazole Ugi product is found and not traces of other possible Ugi type reactions. Based on this reaction pathway we have designed the synthesis of novel tetrazole-peptidomimetics. A high level of structural diversity can be achieved using this isocyanide based multicomponent reaction (IMCR), providing a platform for the production of functionalized building blocks for novel bioactive molecules and nontraditional scaffolds which previously were not accessible...
July 27, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28704057/peptide-macrocyclization-assisted-by-traceless-turn-inducers-derived-from-ugi-peptide-ligation-with-cleavable-and-resin-linked-amines
#16
Alfredo R Puentes, Micjel C Morejón, Daniel G Rivera, Ludger A Wessjohann
A multicomponent approach enabling the installation of turn-inducing moieties that facilitate the macrocyclization of short and medium-size oligopeptides is described. The strategy comprises the Ugi ligation of peptide carboxylic acids and isocyanopeptides in the presence of aldehydes and acid or photolabile amines followed by cyclization and cleavage of the backbone N-substituents to render canonical cyclopeptides. Implementing the approach on solid phase with the use of Rink amide resins led to a new class of backbone amide linker strategy...
July 13, 2017: Organic Letters
https://www.readbyqxmd.com/read/28703181/association-between-helicobacter-pylori-infection-and-long-term-outcome-in-patients-with-drug-eluting-stent-implantation
#17
Rui Wang, Lei-Lei Chen, De-Zhao Wang, Bu-Xing Chen
To investigate the relationship between Helicobacter pylori (Hp) infection and the long-term outcome in acute coronary syndrome (ACS) patients with drug-eluting stent (DES) implantation and so as to explore the significance of Hp eradication therapy in preventing major adverse cardiac events (MACE) and upper gastrointestinal bleeding (UGIB). 539 ACS patients with DES implantation from January 1, 2010 to December 31, 2012 were analyzed. All the patients were divided into two groups according to the result of (13)C urea breath test...
July 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28702849/synthesis-of-formula-see-text-amino-1-3-dicarbonyl-compounds-via-ugi-flow-chemistry-reaction-access-to-functionalized-1-2-3-triazoles
#18
Stanley N S Vasconcelos, Evelin Fornari, Ignez Caracelli, Hélio A Stefani
The Ugi multicomponent reaction has been used as an important synthetic route to obtain compounds with potential biological activity. We present the rapid and efficient synthesis of [Formula: see text]-amino-1,3-dicarbonyl compounds in moderate to good yields via Ugi flow chemistry reactions performed with a continuous flow reactor. Such [Formula: see text]-amino-1,3-dicarbonyl compounds can act as precursors for the production of [Formula: see text]-amino acids via hydrolysis of the ethyl ester group as well as building blocks for the synthesis of novel compounds with the 1,2,3-triazole ring...
July 12, 2017: Molecular Diversity
https://www.readbyqxmd.com/read/28696114/total-synthesis-and-antibacterial-investigation-of-plusbacin-a3
#19
Akira Katsuyama, Atmika Paudel, Suresh Panthee, Hiroshi Hamamoto, Toru Kawakami, Hironobu Hojo, Fumika Yakushiji, Satoshi Ichikawa
The total synthesis of plusbacin A3 (1) has been accomplished using a solvent-dependent diastereodivergent Joullié-Ugi three-component reaction (JU-3CR) as a key step. Two trans-3-hydroxy-l-proline residues were constructed by combining the JU-3CR with a convertible isocyanide strategy. Subsequent peptide coupling and macrolactamization afforded plusbacin A3. Investigating the antibacterial activity of 1 compared with that of its dideoxy analogue revealed that the threo-β-hydroxyaspartic acid residues are essential for antibacterial activity...
July 11, 2017: Organic Letters
https://www.readbyqxmd.com/read/28691783/two-steps-towards-complex-and-artificial-medium-and-macrocycles
#20
Alexander Doemling, Rudrakshula Madhavachary, Eman M M Abdelraheem, Arianna Rossetti, Aleksandra Twarda-Clapa, Bogdan Musielak, Katarzyna Kurpiewska, Justyna Kalinowska-Tłuścik, Tad A Holak
The design and synthesis of head-to-tail linked artificial macrocycles using the Ugi-reaction has been developed. This synthetic approach in just two steps is unprecedented short, efficient and works over a wide range of medium and macrocyclic loop sizes. The substrate scope and functional group tolerance is exceptional. Using this approach, we have synthesized 39 novel macrocycles including for example tylosin and we incorporate glycosylated macrocycles as well by two or even one single synthetic operation...
July 10, 2017: Angewandte Chemie
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