Publications by authors named "Haike Zhang"

Background Administration of a gadolinium-based contrast material is widely considered obligatory for follow-up imaging of patients with multiple sclerosis (MS). However, advances in MRI have substantially improved the sensitivity for detecting new or enlarged lesions in MS. Purpose To investigate whether the use of contrast material has an effect on the detection of new or enlarged MS lesions and, consequently, the assessment of interval progression.

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Magnetic resonance imaging (MRI) scans play a pivotal role in the evaluation of patients presenting with a clinically isolated syndrome (CIS), as these may depict brain lesions suggestive of an inflammatory cause. We hypothesized that it is possible to predict the conversion from CIS to multiple sclerosis (MS) based on the baseline MRI scan by studying image features of these lesions. We analyzed 84 patients diagnosed with CIS from a prospective observational single center cohort.

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We developed a tool that performs longitudinal subtraction of 3D double inversion recovery (DIR) images in follow-up magnetic resonance (MR) examinations of patients with multiple sclerosis. As DIR sequences show a high lesion-to-parenchyma contrast, we hypothesized that such a tool might lead to increased sensitivity for new lesions as well as to speeding up the routine clinical work-up of follow-up MR imaging in multiple sclerosis by directly visualizing new lesions. DIR subtraction images of serial MR examinations were calculated in 106 patients with multiple sclerosis.

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1,2,3-Thiadiazoles, an important synthetic active substructure, are nowadays becoming one of the important branches in novel pesticide development. To develop pesticide candidates with diverse biological activities and probe their structure-activity relationship, three series of 5-methyl-1,2,3-thiadiazoles were rationally designed and synthesized using a simple and convenient one-step synthetic procedure via Ugi reaction. Biological activities of the target compounds including fungicidal activity, antivirus activity in vitro and in vivo, and systemic acquired resistance were systematically evaluated.

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Heterocyclic compounds play an important role as the main sources of lead molecules of agrochemicals. Synthesis and biological activity of thiadiazole-containing 1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles were seldom reported. To find novel lead compounds with various biological activities, a series of 6-substituted-3-(4-methyl-1,2,3-thiadiazolyl)[1,2,4]triazolo[3,4-b][1,3,4]thiadizoles were rationally designed and synthesized according to the principle of combinations of bioactive substructures by the condensation of 3-(4-methyl-1,2,3-thiadiazolyl)-4-amino-1,2,4-triazole-5-thione with various carboxylic acids and phosphorus oxychloride.

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The Ugi reaction is a green and rapid one-pot reaction for lead derivation. To develop novel candidate pesticides with diverse biological activities, two series of 4-methyl-1,2,3-thiadiazole derivatives containing active substructures of 3-chloro-4-methylphenyl or 3-fluoro-4-methylphenyl, respectively, were rationally designed and synthesized via Ugi reaction according to the principle of combinations of bioactive substructures. All of the structures of newly synthesized compounds were confirmed by proton nuclear magnetic resonance and high-resolution mass spectrometry.

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Elicitors provide a broad spectrum of systemic acquired resistance by altering the physical and physiological status of the host plants and, therefore, are among the most successful directions in modern pesticide development for plant protection. To develop a novel elicitor with highly systemic acquired resistance, two series of thiazole- and oxadiazole-containing thiadiazole derivatives were rationally designed and synthesized according to the principle of combination of bioactive substructures in this work. Their structures were characterized by (1)H nuclear magnetic resonance (NMR), infrared (IR), high-resolution mass spectrometry (HRMS), or elemental analysis.

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