WorldWideScience

Sample records for derivatives causative agents

  1. Voltage-Gated Channels as Causative Agents for Epilepsies

    Directory of Open Access Journals (Sweden)

    Mutasem Abuhamed

    2008-01-01

    Full Text Available Problem statement: Epilepsy is a common neurological disorder that afflicts 1-2% of the general population worldwide. It encompasses a variety of disorders with seizures. Approach: Idiopathic epilepsies were defined as a heterogeneous group of seizure disorders that show no underlying cause .Voltage-gated ion channels defect were recognized etiology of epilepsy in the central nervous system. The aim of this article was to provide an update on voltage-gated channels and their mutation as causative agents for epilepsies. We described the structures of the voltage-gated channels, discuss their current genetic studies, and then review the effects of voltage-gated channels as causative agents for epilepsies. Results: Channels control the flow of ions in and out of the cell causing depolarization and hyper polarization of the cell. Voltage-gated channels were classified into four types: Sodium, potassium calcium ands chloride. Voltage-gated channels were macromolecular protein complexes within the lipid membrane. They were divided into subunits. Each subunit had a specific function and was encoded by more than one gen. Conclusion: Current genetic studies of idiopathic epilepsies show the importance of genetic influence on Voltage-gated channels. Different genes may regulate a function in a channel; the channel defect was directly responsible for neuronal hyper excitability and seizures.

  2. A compendium of causative agents of occupational asthma.

    Science.gov (United States)

    Baur, Xaver

    2013-05-24

    The objective is to provide an evidence-based compendium of allergenic and irritant agents that are known to cause occupational asthma in order to improve diagnostics and disease management. Two previously published reviews from our group utilized database searches to identify studies which were then rated according to the Scottish Intercollegiate Guideline Network (SIGN) grading system. The evidence level for each causative agent or worksite was graded using the Royal College of General Practitioners (RCGP) three-star system. Approximately 3,000 relevant papers were identified, which covered 372 different causes of allergic and 184 different causes of irritant occupational asthma. The highest level achieved using the SIGN grading system was 2++, indicating a high quality study with a very low risk of confounding or bias and a high probability of a causal relationship. Using the modified RCGP three-star grading system, the strongest evidence of association with an individual agent or worksite ('***') was found for exposure to laboratory animals. Associations with moderate evidence level ('**') were obtained for a) the allergenic agents or worksites: alpha-amylase from Aspergillus oryzae, various enzymes from Bacillus subtilis, papain, bakeries, western red cedar, latex, psyllium, storage mites, rat, carmine, egg proteins, Atlantic salmon, fishmeal, Norway lobster, prawn, snow crab, seafood, trout and turbot, reactive dyes, b) the irritant agents or worksites: benzene-1,2,4-tricarboxylic acid, 1,2- anhydride [trimellitic anhydride], chlorine, cobalt, cement, environmental tobacco smoke, grain, welding fumes, construction work, swine confinement, World Trade Center disaster 2001, and c) agents or worksites causing allergic as well as irritant occupational asthma, included farming, poultry confinement, various isocyanates and platinum salts. A low evidence level (RCGP) was obtained for 84 agents or worksites (42 from each group), providing a total of 141 conditions

  3. [Sensitivity of nosocomial purulent-septic infection causative agents to disinfection agents and antibiotics].

    Science.gov (United States)

    Sergevnin, V I; Kliukina, T V; Kliuchareva, N M; Volkova, E O; Kudriavtseva, L G

    2014-01-01

    Study the sensitivity of nosocomial purulent-septic infection (PSI) causative agents to disinfectants (DA) and antibiotics (AB). Sensitivity to DA and AB of 209 PSI causative agent strains isolated from patients and the environment of 2 obstetric and 3 surgical hospitals was studied in 2009-2011. Sensitivity to DA of 94 strains and to AB of 189 strains of Pseudomonas aeruginosa isolated from patients with signs of PSI of reanimation and intensive therapy and surgical departments of a multi-field hospital was studied in 2012. Sensitivity to DA was determined on test-surfaces and in solution according to guidelines by V.V. Shkarin et al., 2010; sensitivity to AB - by disc-diffusion method. Among PSI causative agents resistant to DA the portion of poly-antibiotic resistant strains is higher than among microorganisms sensitive to DA, and among antibiotic resistant bacteria the number of strains resistant to DA is higher than among sensitive to antibiotics. The increase of resistance to DA and AB of P. aeruginosa strains is observed in parallel to the increase of volume of the antibacterial preparations used. The results obtained give evidence of the possibility of formation of combined (associated) resistance to DA and AB by nosocomial PSI causative agents against the background of increase of their consumption.

  4. Interaction between mycotoxins and causative agents of swine infective diseases

    Directory of Open Access Journals (Sweden)

    Prodanov-Radulović Jasna Z.

    2011-01-01

    Full Text Available Mycotoxins are secondary metabolites of fungi that can contaminate animal feeds at all stages of food production chain. Consumption of feed contaminated with mycotoxins may result in immunosuppression, which represents a predisposing factor for occurence of infectious diseases in livestock. The influence on immune system is of special interest in swine industry. The technology on swine farms demands frequent vaccinations, which may be a problem in the case of immunocompromised animals. The aim of this paper was evaluation of mycotoxin influence on swine farms, as secondary factors for destabilization of animals’ immunological system. Material for this research included the samples from five swine farms, where health disorders, i.e. clinical and patomorphological signs resembling the problem with infectious diseases in different swine categories, were detected. The applied research methods included: epidemiological and clinical evaluation, pathomorphological examination, laboratory testing of bacteriological and virusological tissue originating from dead animals, and microbiological feed testing in order to examine the presence of fungi and mycotoxins. The obtained results indicated the existence of positive interaction between mycotoxins and causative agents of swine infective diseases. Despite continual pharmaco- and immunoprophylaxis in swine, the health problems of bacterial ethiology (colibacilosis, enteroxemia, dysentery, pneumonia, endometritis were detected. From an epidemiological point of view, the presence of mycotoxins in animal feed may induce a breakdown of active immunity and occurrence of disease even in properly vaccinated animals.

  5. Mycetoma in Iran: Causative Agents and Geographic Distribution

    Science.gov (United States)

    Bassiri-Jahromi, Shahindokht

    2014-01-01

    Background: Mycetoma is a chronic granulomatous disease caused by true fungi (eumycetoma) or filamentous bacteria (actinomycetoma). It usually involves the subcutaneous tissue after a traumatic inoculation of the causative organism. We reviewed retrospectively 13 patients with mycetoma. Materials and Methods: This study reports the etiologic agents and distribution of mycetoma in 35 cases from 1994 to2009 in Iran. The diagnostic of mycetoma were confirmed by histopathology and direct preparation, culture techniques, and histopathology of granules and surgical biopsies, radiological examination of the affected site. Results: Mycetoma was identified in 35 patients of 168 suspected patients (20.8%). They occurred in 22 male and 13 females. Their ages ranged from 14 to 80 years. The duration of the disease ranged from two months to 38 years. Sixteen patients had eumycetoma, and 19 patients had actinomycetoma, one of them had mix infections by eumycetoma and actinomycetoma. The majority of the patients were from central and states in south and north of Iran. The feet were most affected site (65.7%) of the cases, followed by hands (25.7%), face (2.8%), and trunk (2.8%), and buttock (2.8%). Most patients (68.5%) were more than 40 year-old. The male to female ratio was 5:3. The disease was abundant among housewife in urban and farmer in rural area of Iran. The most common prevalent mycetoma agents in this study were Actinomyces sp. There was a history of risk factors in 28.6% of patients in this study. Conclusion: Mycetoma occasionally occurs particularly in the South, Central, and North of Iran, and seen most often in persons, who live in hot, humid climates. If there are risk factors for invasive fungal infections traumatic inoculation with any fungus may result in rapid local spread and systemic disease, often with fatal outcome. PMID:25284877

  6. Mycetoma in Iran: Causative agents and geographic distribution

    Directory of Open Access Journals (Sweden)

    Shahindokht Bassiri-Jahromi

    2014-01-01

    Full Text Available Background: Mycetoma is a chronic granulomatous disease caused by true fungi (eumycetoma or filamentous bacteria (actinomycetoma. It usually involves the subcutaneous tissue after a traumatic inoculation of the causative organism. We reviewed retrospectively 13 patients with mycetoma. Materials and Methods: This study reports the etiologic agents and distribution of mycetoma in 35 cases from 1994 to2009 in Iran. The diagnostic of mycetoma were confirmed by histopathology and direct preparation, culture techniques, and histopathology of granules and surgical biopsies, radiological examination of the affected site. Results: Mycetoma was identified in 35 patients of 168 suspected patients (20.8%. They occurred in 22 male and 13 females. Their ages ranged from 14 to 80 years. The duration of the disease ranged from two months to 38 years. Sixteen patients had eumycetoma, and 19 patients had actinomycetoma, one of them had mix infections by eumycetoma and actinomycetoma. The majority of the patients were from central and states in south and north of Iran. The feet were most affected site (65.7% of the cases, followed by hands (25.7%, face (2.8%, and trunk (2.8%, and buttock (2.8%. Most patients (68.5% were more than 40 year-old. The male to female ratio was 5:3. The disease was abundant among housewife in urban and farmer in rural area of Iran. The most common prevalent mycetoma agents in this study were Actinomyces sp. There was a history of risk factors in 28.6% of patients in this study. Conclusion: Mycetoma occasionally occurs particularly in the South, Central, and North of Iran, and seen most often in persons, who live in hot, humid climates. If there are risk factors for invasive fungal infections traumatic inoculation with any fungus may result in rapid local spread and systemic disease, often with fatal outcome.

  7. Mycetoma in iran: causative agents and geographic distribution.

    Science.gov (United States)

    Bassiri-Jahromi, Shahindokht

    2014-09-01

    Mycetoma is a chronic granulomatous disease caused by true fungi (eumycetoma) or filamentous bacteria (actinomycetoma). It usually involves the subcutaneous tissue after a traumatic inoculation of the causative organism. We reviewed retrospectively 13 patients with mycetoma. This study reports the etiologic agents and distribution of mycetoma in 35 cases from 1994 to2009 in Iran. The diagnostic of mycetoma were confirmed by histopathology and direct preparation, culture techniques, and histopathology of granules and surgical biopsies, radiological examination of the affected site. Mycetoma was identified in 35 patients of 168 suspected patients (20.8%). They occurred in 22 male and 13 females. Their ages ranged from 14 to 80 years. The duration of the disease ranged from two months to 38 years. Sixteen patients had eumycetoma, and 19 patients had actinomycetoma, one of them had mix infections by eumycetoma and actinomycetoma. The majority of the patients were from central and states in south and north of Iran. The feet were most affected site (65.7%) of the cases, followed by hands (25.7%), face (2.8%), and trunk (2.8%), and buttock (2.8%). Most patients (68.5%) were more than 40 year-old. The male to female ratio was 5:3. The disease was abundant among housewife in urban and farmer in rural area of Iran. The most common prevalent mycetoma agents in this study were Actinomyces sp. There was a history of risk factors in 28.6% of patients in this study. Mycetoma occasionally occurs particularly in the South, Central, and North of Iran, and seen most often in persons, who live in hot, humid climates. If there are risk factors for invasive fungal infections traumatic inoculation with any fungus may result in rapid local spread and systemic disease, often with fatal outcome.

  8. APPROUSH TO SPECIFIC DIAGNOSTICS OF CAUSATIVE AGENTS OF INFECTIOUS ENDOCARDIDIS

    Directory of Open Access Journals (Sweden)

    Katsapov D.V.

    2015-05-01

    Full Text Available Introduction. Increased level of morbidity of infective endocarditis (IE connected with new risk factors: intravenous drug use, cardiosurgical interventions, hemodialysis brought new clinical forms of the disease. As it shown in a literature main pathogenetic factors of IE are bacteraemia, trauma of endocardium and invasive medical procedures. Very typical pathogens are streptococci and staphylococci. Most typically mitral and aortal valves are affected with spreading of vegetations on surrounding media. Discussion. IE is polyetiologic disease caused by more than 128 microorganisms, and still a challenge for medical professionals. Detection a causative agent is critical for proper specific treatment. In different sources data on percentage of proven cases very according to country and different medical centres reflecting different local epidemiology of IE, diagnostic criteria and protocols. Culture negative infectious endocarditis (CNIE is considered in case of obtaining of three negative results of cultivation of samples on a standard blood agar during 7 days and subculturing. CNIE incidence very form 2% to 33% according to different researches and higher in cases of community acquired infection and reseeding antibacterial treatment. Some of cases of CNIE caused by gram - negative fastidious microorganisms - Haemophilus parainfluenzae, Actinobacillus, Actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, Kingella kingae, with united in HACEK group according to their properties to colonize oropharynx and requirement in special conditions and duration of incubation. Detection of some intracellular bacteria, such as C. burnetti and Bartonella spp. require immunological methods of detection, histological methods and of PCR. Conclusion. In case of diagnostics of patients with CNIE it is necessary to use a combination of prolonged subculturing of serum, emboli and histologic material on blood agar with microscopy by Warthin

  9. Rapid identification of black grain eumycetoma causative agents using rolling circle amplification

    NARCIS (Netherlands)

    Ahmed, Sarah A; Gerrits van den Ende, Bert; Fahal, Ahmed H; van de Sande, Wendy W J; de Hoog, G S

    2014-01-01

    Accurate identification of mycetoma causative agent is a priority for treatment. However, current identification tools are far from being satisfactory for both reliable diagnosis and epidemiological investigations. A rapid, simple, and highly efficient molecular based method for identification of

  10. Causative agents of superficial mycoses in Istanbul, Turkey: retrospective study.

    Science.gov (United States)

    Koksal, Fatma; Er, Emine; Samasti, Mustafa

    2009-09-01

    The aim of the present study was to determine the percentage of agents, which can give rise to superficial fungal infections in Istanbul, Turkey. Between 2000 and 2007, the clinical samples collected from 8,200 patients attending the outpatient Dermatology Clinic at Mihrimahsultan Medical Center were examined by direct microscopy and culture. Pathogen fungi were detected in 5,722 of the patients. Of the isolates were 4,218 (74%) dermatophytes, 1,196 (21%) Candida sp., 170 (3%) Malassezia furfur, and 138 (2%) Trichosporon sp. Among the dermatophytes, Trichophyton sp. was the most common isolate followed by Epidermophyton floccosum (243) and Microsporum sp. Among the Candida species, C. albicans (549) was also frequently found. Onychomycosis was the most prevalent type of infection, followed by tinea pedis, tinea cruris, tinea corporis, and tinea capitis. In conclusion, our study showed that the most common isolated agents from superficial infections were T. rubrum being Candida sp. the second most prevalent.

  11. Fusarium solani : A causative agent of skin and nail infections

    Directory of Open Access Journals (Sweden)

    Thomas S Kuruvilla

    2012-01-01

    Full Text Available Fusarium spp are non-dermatophytic hyaline moulds found as saprophytes and plant pathogens. Human infections are probably a result of various precipitating predisposing factors of impaired immune status. Immunocompetent individuals of late are also vulnerable to various unassuming saprophytic and plant pathogens. To stress the need to identify correctly and institute appropriate antifungal therapy in newly emerging human fungal infectious agents. Repeated mycological sampling of the skin and nails of the suspected fungal infection were processed as per the standard format including direct microscopy and fungal culture on Sabouraud′s dextrose agar. The fungus was isolated as Fusarium solani. Fusarium is an important plant pathogen and soil saprophyte. Infection is acquired by direct inoculation or inhalation of spores. It is associated with a variety of diseases like keratitis, onychomycosis, eumycetoma, skin lesions and disseminated diseases.

  12. Respiratory picornaviruses and respiratory syncytial virus as causative agents of acute expiratory wheezing in children

    NARCIS (Netherlands)

    T. Jartti; P. Lehtinen; T. Vuorinen; A.D.M.E. Osterhaus (Albert); O. Ruuskanen; R. Österback (Riika); B.G. van den Hoogen (Bernadette)

    2004-01-01

    textabstractWe studied the viral etiology of acute expiratory wheezing (bronchiolitis, acute asthma) in 293 hospitalized children in a 2-year prospective study in Finland. A potential causative viral agent was detected in 88% of the cases. Eleven different viruses were represented. Respiratory

  13. [Some properties of plasmocoagulase of the causative agents of glanders and melioidosis].

    Science.gov (United States)

    Narbutovich, N I; Lomova, L V; Ageeva, N P; Kucheriaeva, V T; Seimova, I K

    2005-01-01

    Criteria for the evaluation of the plasmocoagulase activity of natural isolates and mutant strains of the causative agents of glanders and melioidosis were worked out, which made it possible to subdivide them by this sign into pathogens with high, moderate and low activity. Plasmocoagulase produced by pathogenic Burkholderia was shown to be a thermolabile enzyme, comparatively stable with respect to the action of such chemico-biological agents as hydrogen peroxide and chloramine.

  14. [Molecular-genetic approaches to diagnosis and intraspecific typing of causative agents of glanders and melioidosis].

    Science.gov (United States)

    Antonov, V A; Iliukhin, V I

    2005-01-01

    Pathogenic Burkholderia--Burkholderia mallei and Burkholderia pseudomallei--are causative agents of glanders and melioidosis, severe infectious diseases of man and animals. They are regarded as potential agents of bioterrorism. The existing bacteriological and immunological methods of identification of B. mallei and B. pseudomallei are not efficient enough for the rapid diagnosis and typing of strains. Described in the paper are molecular methods of detection of the agents by PCR, hybridization and strain typing made on the basis of bacterial total cell protein profiles, RAPD, ribotyping as well as of plasmid and DNA microrestriction analyses.

  15. [Formation of microbial biofilms in causative agents of acute and chronic pyelonephritis].

    Science.gov (United States)

    Lagun, L V; Atanasova, Iu V; Tapal'skiĭ, D V

    2013-01-01

    Study the intensity of formation of microbial biofilms by Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus strains isolated during various forms of pyelonephritis. 150 clinical isolates of microorganisms isolated from urine ofpatientswith acute and chronic pyelonephritiswere included into the study. Determination of intensity of film-formation was carried out by staining of the formed biofilms by crystal violet with consequent extraction of the dye and measurement of its concentration in washout solution. Among causative agents ofpyelonephritis P. aeruginosa isolates had the maximum film-forming ability. The intensity of biofilm formation of these isolates was 2-3 time higher than staphylococcus and enterobacteria strains. Strains isolated from patients with chronic pyelonephritis by ability to form biofilms significantly surpassed strains isolated from acute pyelonephritis patients. A higher ability to form microbial biofilms for microorganisms--causative agents of pyelonephritis progressing against the background ofurolithiasis was noted. The ability to form biofilms is determined by both causative agent species and character of the infectious process in which this microorganism participates. Intensive formation of biofilms by E. coli, P. aeruginosa, K. pneumoniae, S. aureus clinical isolates may be an important factor of chronization of urinary tract infections.

  16. [Identification of the causative agents of glanders and melioidosis by polymerase chain reaction].

    Science.gov (United States)

    Tkachenko, G A; Antonov, V A; Zamaraev, V S; Iliukhin, V I

    2003-01-01

    Burkholderia mallei and B. pseudomallei are causative agents of glanders and melioidosis, respectively, i.e. severe and fatal infection diseases of man and animal. The computer-based analysis of the 23S rRNA gene sites was used for selecting the primers. Two pairs of primers were chosen for the identification of B. mallei and Bpseudomallei. DNAs from 48 B. pseudomallei and 15 strains of B. mallei, unlike from other geterological bacteria, were positively amplified. Therefore, the method of polymerase chain reaction can be used in laboratory diagnosis of glanders and melioidosis.

  17. Identification of the causative agent of cutaneous leishmaniasis in Chichaoua province, Morocco

    Directory of Open Access Journals (Sweden)

    Rhajaoui M.

    2012-02-01

    Full Text Available Cutaneous leishmaniasis (CL in Morocco is caused by three species, Leishmania major, L. tropica and L. infantum. CL has been known in Chichaoua province since 2000. Using DNA extracted from microscopic slides and parasite cultures, collected in the years 2006 and 2009, we identified for the first time L. tropica as the causative agent of CL in this region. Species identification was achieved by performing the ITS1-PCR-RFLP approach. By using this method it was possible to identify parasites in Giemsa stained slides containing less than five parasites per oil-immersion field even they were conserved for up to four months.

  18. Metal-dependent gene regulation in the causative agent of Lyme disease

    OpenAIRE

    2013-01-01

    Borrelia burgdorferi (Bb) is the causative agent of Lyme disease transmitted to humans by ticks of the Ixodes spp. Bb is a unique bacterial pathogen because it does not require iron (Fe2+) for its metabolism. Bb encodes a ferritin-like Dps homolog called NapA (also called BicA), which can bind Fe or copper (Cu2+), and a manganese (Mn2+) transport protein, Borrelia metal transporter A (BmtA); both proteins are required for colonization of the tick vector, but BmtA is also required for the muri...

  19. A new unifying hypothesis for lathyrism, konzo and tropical ataxic neuropathy: nitriles are the causative agents.

    Science.gov (United States)

    Llorens, Jordi; Soler-Martín, Carla; Saldaña-Ruíz, Sandra; Cutillas, Blanca; Ambrosio, Santiago; Boadas-Vaello, Pere

    2011-03-01

    Konzo and lathyrism are associated with consumption of cassava and grass pea, respectively. Cassava consumption has also been associated with a third disease, tropical ataxic neuropathy (TAN). This review presents a new unifying hypothesis on the causative agents for these diseases: namely, that they are nitriles, compounds containing cyano groups. The diseases may be caused by different but similar nitriles through direct neurotoxic actions not mediated by systemic cyanide release. Both cassava and Lathyrus contain nitriles, and other unidentified nitriles can be generated during food processing or in the human body. Available data indicate that several small nitriles cause a variety of neurotoxic effects. In experimental animals, 3,3'-iminodipropionitrile (IDPN), allylnitrile and cis-crotononitrile cause sensory toxicity, whereas hexadienenitrile and trans-crotononitrile induce selective neuronal degeneration in discrete brain regions. IDPN also induces a neurofilamentous axonopathy, and dimethylaminopropionitrile is known to cause autonomic (genito-urinary) neurotoxicity in both humans and rodents. Some of these actions depend on metabolic bioactivation of the parental nitriles, and sex- and species-dependent differences in susceptibility have been recorded. Recently, neuronal degeneration has been found in rats exposed to acetone cyanohydrin. Taken together, the neurotoxic properties of nitriles make them excellent candidates as causative agents for konzo, lathyrism and TAN. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. The genome sequence of Clostridium tetani, the causative agent of tetanus disease.

    Science.gov (United States)

    Bruggemann, Holger; Baumer, Sebastian; Fricke, Wolfgang Florian; Wiezer, Arnim; Liesegang, Heiko; Decker, Iwona; Herzberg, Christina; Martinez-Arias, Rosa; Merkl, Rainer; Henne, Anke; Gottschalk, Gerhard

    2003-02-04

    Tetanus disease is one of the most dramatic and globally prevalent diseases of humans and vertebrate animals, and has been reported for over 24 centuries. The manifestation of the disease, spastic paralysis, is caused by the second most poisonous substance known, the tetanus toxin, with a human lethal dose of approximately 1 ng/kg. Fortunately, this disease is successfully controlled through immunization with tetanus toxoid; nevertheless, according to the World Health Organization, an estimated 400,000 cases still occur each year, mainly of neonatal tetanus. The causative agent of tetanus disease is Clostridium tetani, an anaerobic spore-forming bacterium, whose natural habitat is soil, dust, and intestinal tracts of various animals. Here we report the complete genome sequence of toxigenic C. tetani E88, a variant of strain Massachusetts. The genome consists of a 2,799,250-bp chromosome encoding 2,372 ORFs. The tetanus toxin and a collagenase are encoded on a 74,082-bp plasmid, containing 61 ORFs. Additional virulence-related factors could be identified, such as an array of surface-layer and adhesion proteins (35 ORFs), some of them unique to C. tetani. Comparative genomics with the genomes of Clostridium perfringens, the causative agent of gas gangrene, and Clostridium acetobutylicum, a nonpathogenic solvent producer, revealed a remarkable capacity of C. tetani: The organism can rely on an extensive sodium ion bioenergetics. Additional candidate genes involved in the establishment and maintenance of a pathogenic lifestyle of C. tetani are presented.

  1. Rapid Identification of Black Grain Eumycetoma Causative Agents Using Rolling Circle Amplification

    Science.gov (United States)

    Ahmed, Sarah A.; van den Ende, Bert H. G. Gerrits; Fahal, Ahmed H.; van de Sande, Wendy W. J.; de Hoog, G. S.

    2014-01-01

    Accurate identification of mycetoma causative agent is a priority for treatment. However, current identification tools are far from being satisfactory for both reliable diagnosis and epidemiological investigations. A rapid, simple, and highly efficient molecular based method for identification of agents of black grain eumycetoma is introduced, aiming to improve diagnostic in endemic areas. Rolling Circle Amplification (RCA) uses species-specific padlock probes and isothermal DNA amplification. The tests were based on ITS sequences and developed for Falciformispora senegalensis, F. tompkinsii, Madurella fahalii, M. mycetomatis, M. pseudomycetomatis, M. tropicana, Medicopsis romeroi, and Trematosphaeria grisea. With the isothermal RCA assay, 62 isolates were successfully identified with 100% specificity and no cross reactivity or false results. The main advantage of this technique is the low-cost, high specificity, and simplicity. In addition, it is highly reproducible and can be performed within a single day. PMID:25474355

  2. Rapid identification of black grain eumycetoma causative agents using rolling circle amplification.

    Directory of Open Access Journals (Sweden)

    Sarah A Ahmed

    2014-12-01

    Full Text Available Accurate identification of mycetoma causative agent is a priority for treatment. However, current identification tools are far from being satisfactory for both reliable diagnosis and epidemiological investigations. A rapid, simple, and highly efficient molecular based method for identification of agents of black grain eumycetoma is introduced, aiming to improve diagnostic in endemic areas. Rolling Circle Amplification (RCA uses species-specific padlock probes and isothermal DNA amplification. The tests were based on ITS sequences and developed for Falciformispora senegalensis, F. tompkinsii, Madurella fahalii, M. mycetomatis, M. pseudomycetomatis, M. tropicana, Medicopsis romeroi, and Trematosphaeria grisea. With the isothermal RCA assay, 62 isolates were successfully identified with 100% specificity and no cross reactivity or false results. The main advantage of this technique is the low-cost, high specificity, and simplicity. In addition, it is highly reproducible and can be performed within a single day.

  3. Rapid identification of black grain eumycetoma causative agents using rolling circle amplification.

    Science.gov (United States)

    Ahmed, Sarah A; van den Ende, Bert H G Gerrits; Fahal, Ahmed H; van de Sande, Wendy W J; de Hoog, G S

    2014-12-01

    Accurate identification of mycetoma causative agent is a priority for treatment. However, current identification tools are far from being satisfactory for both reliable diagnosis and epidemiological investigations. A rapid, simple, and highly efficient molecular based method for identification of agents of black grain eumycetoma is introduced, aiming to improve diagnostic in endemic areas. Rolling Circle Amplification (RCA) uses species-specific padlock probes and isothermal DNA amplification. The tests were based on ITS sequences and developed for Falciformispora senegalensis, F. tompkinsii, Madurella fahalii, M. mycetomatis, M. pseudomycetomatis, M. tropicana, Medicopsis romeroi, and Trematosphaeria grisea. With the isothermal RCA assay, 62 isolates were successfully identified with 100% specificity and no cross reactivity or false results. The main advantage of this technique is the low-cost, high specificity, and simplicity. In addition, it is highly reproducible and can be performed within a single day.

  4. Respiratory picornaviruses and respiratory syncytial virus as causative agents of acute expiratory wheezing in children.

    Science.gov (United States)

    Jartti, Tuomas; Lehtinen, Pasi; Vuorinen, Tytti; Osterback, Riika; van den Hoogen, Bernadette; Osterhaus, Albert D M E; Ruuskanen, Olli

    2004-06-01

    We studied the viral etiology of acute expiratory wheezing (bronchiolitis, acute asthma) in 293 hospitalized children in a 2-year prospective study in Finland. A potential causative viral agent was detected in 88% of the cases. Eleven different viruses were represented. Respiratory syncytial virus (RSV) (27%), enteroviruses (25%), rhinovirus (24%), and nontypable rhino/enterovirus (16%) were found most frequently. In infants, RSV was found in 54% and respiratory picornaviruses (rhinovirus and enteroviruses) in 42% of the cases. In older children, respiratory picornaviruses dominated (65% of children ages 1-2 years and 82% of children ages > or =3 years). Human metapneumovirus was detected in 4% of all children and in 11% of infants. To prevent and treat acute expiratory wheezing illnesses in children, efforts should be focused on RSV, enterovirus, and rhinovirus infections.

  5. [Etiological structure and resistance to antibacterial drugs of causative agents of cross infection in Donetsk].

    Science.gov (United States)

    Varenko, Iu S; Klochkov, A E; Revenko, T A; Tkachenko, S V; Fedorchenko, A M; Elagina, A B; Lebedeva, N Iu

    1991-02-01

    Tests for hemocultures were performed in 51 patients with clinical diagnoses of sepsis treated in a reanimation unit. Microbial cultures were isolated from 30 patients (58.9 per cent). Staphylococci in pure cultures and associations were the causative agents of sepsis in 26 patients (86.4 per cent). The cultures of E. coli, Y. enterocolitica and Streptococcus faecalis were isolated from 2, 1 and 1 patients, respectively. Pus specimens from 111 patients with postinjection suppuration were tested and staphylococci in pure cultures and associations were detected in 90 patients (81.8 per cent). The cultures of P. vulgaris, Streptococcus pyogenes, E. coli, Str. faecalis, Enterobacter spp. and Pseudomonas aeruginosa were isolated from 10, 5, 3, 1, 1 and 1 patients, respectively. The results showed that Staphylococci played the leading role in development of the hospital infections. Treatment of such patients should be performed with an account of antibioticograms since many strains are resistant to various antibiotics.

  6. Community-acquired urinary tract infections: Causative agents and their resistance to antimicrobial drugs

    Directory of Open Access Journals (Sweden)

    Đorđević Zorana

    2016-01-01

    Full Text Available Background/Aim. Urinary tract infections (UTIs are among the most common infections in outpatients. The aim of this study was to define the causative agents of urinary tract infections and their resistance to antimicrobial drugs in the urban area of central Serbia, as well as to evaluate eventual differences associated with age and gender of the patients. Methods. This retrospective study analysed data taken from routine, consecutively collected urine cultures of outpatients with symptomatic UTIs, collected from the Department of Microbiology, Institute of Public Health in Kragujevac, Serbia, from January 2009 to December 2013. Results. There were 71,905 urine cultures, and 24,713 (34.37% of them were positive for bacterial pathogens. The most common pathogen was Escherichia coli (E. coli (56.56%, followed by Klebsiella spp. (16.20%, Proteus spp. (14.68%, Enterococcus spp. (5.29% and Pseudomonas aeruginosa (3.74%. E. coli and Enterococcus spp. isolation rates were lower in males ≥ 60 years old (23.71% and 4.87%, respectively, while Klebsiella spp. was more prevalent in this group (32.06%. The most common causative agents isolated from 15–29 years old male patients were Enterococcus spp. and Pseudomonas aeruginosa (13.28% each. Among women, the isolation rate of E.coli was high in all age groups (around 70%. Proteus spp. was frequently isolated from females ≤ 14 years old (13.27%, while Klebsiella spp. was the most frequent in the oldest age female group (10.99%. Conclusion. Choice of antibiotics for treatment of UTIs should be governed not only by the local resistance patterns, but also by gender and age of patients.

  7. A novel antiamoebic agent against Acanthamoeba sp. - A causative agent for eye keratitis infection

    Science.gov (United States)

    Kusrini, Eny; Hashim, Fatimah; Azmi, Wan Nor Nadhirah Wan Noor; Amin, Nakisah Mat; Estuningtyas, Ari

    2016-01-01

    The terbium trinitrate.trihydrate.18-crown ether-6, Tb(NO3)3(OH2)3.(18C6) complex has been characterized by elemental analysis, photoluminescence and single X-ray diffraction. The IC50 values were determined based on MTT assay while light and fluorescence microscopy imaging were employed to evaluate the cellular morphological changes. Alkaline comet assay was performed to analyze the DNA damage. The photoluminescence spectrum of the Tb complex excited at 325 nm displayed seven luminescence peaks corresponding to the 5D4 → 7F0, 1, 2, 3, 4, 5, 6 transitions. The cytotoxicity and genotoxicity studies indicated that the Tb(NO3)3(OH2)3.(18C6) complex and its salt form as well as the 18C6 molecule have excellent anti-amoebic activity with very low IC50 values are 7, 2.6 and 1.2 μg/mL, respectively, with significant decrease (p Acanthamoeba viability when the concentration was increased from 0 to 30 μg/mL. The mode of cell death in Acanthamoeba cells following treatment with the Tb complex was apoptosis. This is in contrast to the Tb(NO3)3.6H2O salt- and 18C6 molecule-treated Acanthamoeba, which exhibited necrotic type cells. The percentage of DNA damage following treatment with all the compounds at the IC25 values showed high percentage of type 1 with the % nuclei damage are 14.15 ± 2.4; 46.00 ± 4.2; 36.36 ± 2.4; 45.16 ± 0.6%, respectively for untreated, treated with Tb complex, Tb salt and 18C6 molecule. The work features promising potential of Tb(NO3)3(OH2)3.(18C6) complex as anti-amoebic agent, representing a therapeutic option for Acanthamoeba keratitis infection.

  8. A novel antiamoebic agent against Acanthamoeba sp.--A causative agent for eye keratitis infection.

    Science.gov (United States)

    Kusrini, Eny; Hashim, Fatimah; Azmi, Wan Nor Nadhirah Wan Noor; Amin, Nakisah Mat; Estuningtyas, Ari

    2016-01-15

    The terbium trinitrate.trihydrate.18-crown ether-6, Tb(NO3)3(OH2)3.(18C6) complex has been characterized by elemental analysis, photoluminescence and single X-ray diffraction. The IC50 values were determined based on MTT assay while light and fluorescence microscopy imaging were employed to evaluate the cellular morphological changes. Alkaline comet assay was performed to analyze the DNA damage. The photoluminescence spectrum of the Tb complex excited at 325 nm displayed seven luminescence peaks corresponding to the (5)D4→(7)F(0, 1, 2, 3, 4, 5, 6) transitions. The cytotoxicity and genotoxicity studies indicated that the Tb(NO3)3(OH2)3.(18C6) complex and its salt form as well as the 18C6 molecule have excellent anti-amoebic activity with very low IC50 values are 7, 2.6 and 1.2 μg/mL, respectively, with significant decrease (pAcanthamoeba viability when the concentration was increased from 0 to 30 μg/mL. The mode of cell death in Acanthamoeba cells following treatment with the Tb complex was apoptosis. This is in contrast to the Tb(NO3)3.6H2O salt- and 18C6 molecule-treated Acanthamoeba, which exhibited necrotic type cells. The percentage of DNA damage following treatment with all the compounds at the IC25 values showed high percentage of type 1 with the % nuclei damage are 14.15±2.4; 46.00±4.2; 36.36±2.4; 45.16±0.6%, respectively for untreated, treated with Tb complex, Tb salt and 18C6 molecule. The work features promising potential of Tb(NO3)3(OH2)3.(18C6) complex as anti-amoebic agent, representing a therapeutic option for Acanthamoeba keratitis infection.

  9. Evidence for a close phylogenetic relationship between Melissococcus pluton, the causative agent of European foulbrood disease, and the genus Enterococcus.

    Science.gov (United States)

    Cai, J; Collins, M D

    1994-04-01

    The 16S rRNA gene sequence of Melissococcus pluton, the causative agent of European foulbrood disease, was determined in order to investigate the phylogenetic relationships between this organism and other low-G + C-content gram-positive bacteria. A comparative sequence analysis revealed that M. pluton is a close phylogenetic relative of the genus Enterococcus.

  10. Metal-dependent gene regulation in the causative agent of Lyme disease

    Directory of Open Access Journals (Sweden)

    Bryan eTroxell

    2013-11-01

    Full Text Available Borrelia burgdorferi (Bb is the causative agent of Lyme disease transmitted to humans by ticks of the Ixodes spp. Bb is a unique bacterial pathogen because it does not require iron (Fe2+ for its metabolism. Bb encodes a ferritin-like Dps homolog called NapA (also called BicA, which can bind Fe or copper (Cu2+, and a manganese (Mn2+ transport protein, BmtA; both proteins are required for colonization of the tick vector, but BmtA is also required for the murine host. This demonstrates that Bb’s metal homeostasis is a critical facet of the complex enzootic life cycle between the arthropod and murine hosts. Although metals are known to influence the expression of virulence determinants during infection, it is unknown how or if metals regulate virulence in Bb. Recent evidence demonstrates that Bb modulates the intracellular Mn2+ and zinc (Zn2+ content and, in turn, these metals regulate gene expression through influencing the Ferric Uptake Regulator (Fur homolog Borrelia Oxidative Stress Regulator (BosR. This mini-review focuses on the burgeoning study of metal-dependent gene regulation within Bb.

  11. Acanthamoeba genotypes T3 and T4 as causative agents of amoebic keratitis in Mexico.

    Science.gov (United States)

    Omaña-Molina, Maritza; Vanzzini-Zago, Virginia; Hernandez-Martinez, Dolores; Gonzalez-Robles, Arturo; Salazar-Villatoro, Lizbeth; Ramirez-Flores, Elizabeth; Oregon-Miranda, Eric; Lorenzo-Morales, Jacob; Martinez-Palomo, Adolfo

    2016-02-01

    Free-living amoebae (FLA) are widely distributed worldwide. Some genera included in this group act as opportunistic pathogens causing fatal encephalitis and Acanthamoeba keratitis (AK), a sight-threatening infection of the cornea associated with the use of soft contact lenses that could even end in blindness if an early diagnosis and treatment are not achieved. Furthermore, the numbers of AK cases keep rising worldwide mainly due to an increase of contact lens wearers and lack of hygiene in the maintenance of lenses and their cases. In Mexico, no cases of AK have been described so far although the isolation of other pathogenic FLA such as Naegleria fowleri and Balamuthia mandrillaris from both clinical and environmental sources has been reported. The present study reports two cases of Acanthamoeba keratitis diagnosed in two patients admitted to the Hospital "Luis Sánchez Bulnes" for Blindness Prevention in Mexico City, Mexico. Corneal scrapes and contact lenses were checked for the presence of Acanthamoeba strains in both patients. Strains were axenized after initial isolation to classify at the genotype level. After sequencing the diagnostic fragment 3 (DF3) region located on the 18S ribosomal DNA (rDNA) gene of Acanthamoeba, genotype T3 and genotype T4 were identified in clinical case 1 and 2, respectively. To our knowledge, these are the first reported cases of AK in Mexico in the literature and the first description of Acanthamoeba genotypes T3 and T4 as causative agents of amoebic infection.

  12. Metal-dependent gene regulation in the causative agent of Lyme disease.

    Science.gov (United States)

    Troxell, Bryan; Yang, X Frank

    2013-01-01

    Borrelia burgdorferi (Bb) is the causative agent of Lyme disease transmitted to humans by ticks of the Ixodes spp. Bb is a unique bacterial pathogen because it does not require iron (Fe(2+)) for its metabolism. Bb encodes a ferritin-like Dps homolog called NapA (also called BicA), which can bind Fe or copper (Cu(2+)), and a manganese (Mn(2+)) transport protein, Borrelia metal transporter A (BmtA); both proteins are required for colonization of the tick vector, but BmtA is also required for the murine host. This demonstrates that Bb's metal homeostasis is a critical facet of the complex enzootic life cycle between the arthropod and murine hosts. Although metals are known to influence the expression of virulence determinants during infection, it is unknown how or if metals regulate virulence in Bb. Recent evidence demonstrates that Bb modulates the intracellular Mn(2+) and zinc (Zn(2+)) content and, in turn, these metals regulate gene expression through influencing the Ferric Uptake Regulator (Fur) homolog Borrelia Oxidative Stress Regulator (BosR). This mini-review focuses on the burgeoning study of metal-dependent gene regulation within Bb.

  13. Pathology of camel tuberculosis and molecular characterization of its causative agents in pastoral regions of Ethiopia.

    Directory of Open Access Journals (Sweden)

    Gezahegne Mamo

    Full Text Available A cross sectional study was conducted on 906 apparently healthy camels slaughtered at Akaki and Metehara abattoirs to investigate the pathology of camel tuberculosis (TB and characterize its causative agents using postmortem examination, mycobacteriological culturing, and multiplex polymerase chain reaction (PCR, region of difference-4 (RD4-based PCR and spoligotyping. The prevalence of camel TB was 10.04% (91/906 on the basis of pathology and it was significantly higher in females (χ(2 = 4.789; P = 0.029. The tropism of TB lesions was significantly different among the lymph nodes (χ(2 = 22.697; P = 0.002 and lung lobes (χ(2 = 17.901; P = 0.006. Mycobacterial growth was observed in 34% (31/91 of camels with grossly suspicious TB lesions. Upon further molecular characterization using multiplex PCR, 68% (21/31 of the colonies showed a positive signal for the genus Mycobacterium, of which two were confirmed Mycobacterium bovis (M. bovis by RD4 deletion typing. Further characterization of the two M. bovis at strains level revealed that one of the strains was SB0133 while the other strain was new and had not been reported to the M. bovis database prior to this study. Hence, it has now been reported to the database, and designated as SB1953. In conclusion, the results of the present study have shown that the majority of camel TB lesions are caused by mycobacteria other than Mycobacterium tuberculosis complex. And hence further identification and characterization of these species would be useful towards the efforts made to control TB in camels.

  14. Long-Term Trends in the Epidemiology of Neonatal Sepsis and Antibiotic Susceptibility of Causative Agents

    NARCIS (Netherlands)

    van den Hoogen, Agnes; Gerards, Leo J.; Verboon-Maciolek, Malgorzata A.; Fleer, Andre; Krediet, Tannette G.

    2010-01-01

    Background: In an era with increased maternal antibiotic use, patterns in early- and late-onset sepsis and antibiotic susceptibility may have changed. Objectives: To identify longitudinal trends in causative microorganisms for neonatal sepsis and analyze antibiotic susceptibility of all blood

  15. Long-Term Trends in the Epidemiology of Neonatal Sepsis and Antibiotic Susceptibility of Causative Agents

    NARCIS (Netherlands)

    van den Hoogen, Agnes; Gerards, Leo J.; Verboon-Maciolek, Malgorzata A.; Fleer, Andre; Krediet, Tannette G.

    2010-01-01

    Background: In an era with increased maternal antibiotic use, patterns in early- and late-onset sepsis and antibiotic susceptibility may have changed. Objectives: To identify longitudinal trends in causative microorganisms for neonatal sepsis and analyze antibiotic susceptibility of all blood isolat

  16. Penetratin and derivatives acting as antifungal agents

    NARCIS (Netherlands)

    Masman, Marcelo F.; Rodriguez, Ana M.; Raimondi, Marcela; Zacchino, Susana A.; Luiten, Paul G. M.; Somlai, Csaba; Kortvelyesi, Tamas; Penke, Botond; Enriz, Ricardo D.

    2009-01-01

    The synthesis, in vitro evaluation, and conformational study of RQIKTWFQNRRMKWKK-NH(2) (penetratin) and related derivatives acting as antifungal agents are reported. Penetratin and some of its derivatives displayed antifungal activity against the human opportunistic pathogenic standardized ATCC stra

  17. An efficient hybrid causative event-based approach for deriving the annual flood frequency distribution

    Science.gov (United States)

    Thyer, Mark; Li, Jing; Lambert, Martin; Kuczera, George; Metcalfe, Andrew

    2015-04-01

    Flood extremes are driven by highly variable and complex climatic and hydrological processes. Derived flood frequency methods are often used to predict the flood frequency distribution (FFD) because they can provide predictions in ungauged catchments and evaluate the impact of land-use or climate change. This study presents recent work on development of a new derived flood frequency method called the hybrid causative events (HCE) approach. The advantage of the HCE approach is that it combines the accuracy of the continuous simulation approach with the computational efficiency of the event-based approaches. Derived flood frequency methods, can be divided into two classes. Event-based approaches provide fast estimation, but can also lead to prediction bias due to limitations of inherent assumptions required for obtaining input information (rainfall and catchment wetness) for events that cause large floods. Continuous simulation produces more accurate predictions, however, at the cost of massive computational time. The HCE method uses a short continuous simulation to provide inputs for a rainfall-runoff model running in an event-based fashion. A proof-of-concept pilot study that the HCE produces estimates of the flood frequency distribution with similar accuracy as the continuous simulation, but with dramatically reduced computation time. Recent work incorporated seasonality into the HCE approach and evaluated with a more realistic set of eight sites from a wide range of climate zones, typical of Australia, using a virtual catchment approach. The seasonal hybrid-CE provided accurate predictions of the FFD for all sites. Comparison with the existing non-seasonal hybrid-CE showed that for some sites the non-seasonal hybrid-CE significantly over-predicted the FFD. Analysis of the underlying cause of whether a site had a high, low or no need to use seasonality found it was based on a combination of reasons, that were difficult to predict apriori. Hence it is recommended

  18. Eumycetoma and actinomycetoma--an update on causative agents, epidemiology, pathogenesis, diagnostics and therapy.

    Science.gov (United States)

    Nenoff, P; van de Sande, W W J; Fahal, A H; Reinel, D; Schöfer, H

    2015-10-01

    Mycetoma is a chronic putrid infection of the cutaneous and subcutaneous tissue concerning predominantly the feet, and more rarely other body parts. Mycetoma can be caused by both fungi (eumycetoma) and bacteria (actinomycetoma). Mode of infection is an inoculation of the causative microorganism via small injuries of the skin. The clinical correlate of both forms of mycetoma is tumescence with abscesses, painless nodules, sinuses and discharge. The latter is commonly serous-purulent and contains grains (filamentous granules) which can be expressed for diagnostic purposes. Distinctive for both eumycetoma and actinomycetoma, are the formation of grains. Grains represent microcolonies of the microorganism in vivo in the vital tissue. The most successful treatment option for eumycetomas offers itraconazole in a dosage of 200 mg twice daily. This triazole antifungal is considered as 'gold standard' for eumycetomas. Alternatively, the cheaper ketoconazole was widely used, however, it was currently stopped by the FDA. Actinomycetomas should be treated by the combination of trimethoprim-sulphamethoxazole (co-trimoxazole 80/400 to 160/800 mg per day) and amikacin 15 mg/kg body weight per day. Mycetomas are neglected infections of the poor. They are more than a medical challenge. In rural areas of Africa, Asia and South America mycetomas lead to socio-economic consequences involving the affected patients, their families and the society in general. © 2015 European Academy of Dermatology and Venereology.

  19. Draft Genome Sequence of Fonsecaea nubica Strain CBS 269.64, Causative Agent of Human Chromoblastomycosis.

    Science.gov (United States)

    Costa, Flávia F; de Hoog, Sybren; Raittz, Roberto T; Weiss, Vinicius A; Leão, Aniele C R; Bombassaro, Amanda; Sun, Jiufeng; Moreno, Leandro F; Souza, Emanuel M; Pedrosa, Fabio O; Steffens, Maria Berenice R; Baura, Valter; Tadra-Sfeir, Michele Z; Balsanelli, Eduardo; Najafzadeh, M Javad; Gomes, Renata R; Felipe, Maria S; Teixeira, Marcus; Santos, Germana D; Xi, Liyan; Alves de Castro, Mauro Antônio; Vicente, Vânia A

    2016-08-04

    On the basis of multilocus phylogenetic data, Fonsecaea nubica was described in 2010 as a molecular sibling of F. monophora, an established agent of the human skin disease chomoblastomycosis in tropical zones. Genome analysis of these pathogens is mandatory to identify genes involved in the interaction with host and virulence. Copyright © 2016 Costa et al.

  20. Genetic diversity of the causative agent of ice-ice disease of the seaweed Kappaphycus alvarezii from Karimunjawa island, Indonesia

    Science.gov (United States)

    Syafitri, E.; Prayitno, S. B.; Ma’ruf, W. F.; Radjasa, O. K.

    2017-02-01

    An essential step in investigating the bacterial role in the occurrence of diseases in Kappaphycus alvarezii is the characterization of bacteria associated with this seaweed. A molecular characterization was conducted on the genetic diversity of the causative agents of ice-ice disease associated with K. alvarezii widely known as the main source of kappa carrageenan. K. alvrezii infected with ice-ice were collected from the Karimunjawa island, North Java Sea, Indonesia. Using Zobell 2216E marine agar medium, nine bacterial species were isolated from the infected seaweed. The molecular characterizations revealed that the isolated bacteria causing ice-ice disease were closely related to the genera of Alteromonas, Bacillus, Pseudomonas, Pseudoalteromonas, Glaciecola, Aurantimonas, and Rhodococcus. In order to identify the symptoms causative organisms, the isolated bacterial species were cultured and were evaluated for their pathogenity. Out of 9 species, only 3 isolates were able to cause the ice-ice symptoms and consisted of Alteromonas macleodii, Pseudoalteromonas issachenkonii and Aurantimonas coralicida. A. macleodii showed the highest pathogenity.

  1. Adverse cutaneous drug reactions: Clinical pattern and causative agents in a tertiary care center in South India

    Directory of Open Access Journals (Sweden)

    Pudukadan David

    2004-01-01

    Full Text Available Background: Adverse cutaneous drug reactions (ACDRs are caused by a wide variety of agents. Aims: Our objective was to ascertain the clinical spectrum of ACDRs and the causative drugs in this part of India and to find any risk factors. Methods: Ninety patients with adverse cutaneous drug reactions were recruited for this study during 2001-2003. Hematological and biochemical investigations were done in all of them. The VDRL and HIV (ELISA tests were performed where the underlying risk factors were present. Patch testing, intradermal testing and oral provocation tests were done wherever feasible. Results: The mean age of the patients with cutaneous drug eruptions was 37.06 years. Most of them (52.2% were in the age group of 20-39 years. The male to female ratio was 0.87: 1. The most common eruptions observed were fixed drug eruption (31.1% and maculopapular rash (12.2%, and the most common causes were co-trimoxazole (22.2% and dapsone (17.7%. Conclusion: The pattern of ACDRs and the drugs causing them is remarkably different in our population. Knowledge of these drug eruptions, the causative drugs and the prognostic indicators is essential for the clinician.

  2. IN VITRO STUDY OF ENTAMOEBA HISTOLYTICA CAUSATIVE AGENT OF AMOEBIASIS WITH LEMON JUICE AT DIFFERENT CONCENTRATION SHOWED ANTIAMOEBIC PROPERTIES

    Directory of Open Access Journals (Sweden)

    Shrivastava Bhanu

    2011-09-01

    Full Text Available A species of parasite protozoa Entamoeba histolytica causing amoebiasis and amoebic dysentery characteristic include a single nucleus containing a small central karyosome and peripheral chromatin that is finely and regularly beaded. This is a single celled parasitic animal, that infects predominantly humans and other primates. Amoebic infection was first described by Fedor Losch in 1875 in St. Petersburg. In 1890, Sir William Osler reported the first North American case of amoebiasis when he observed amoebae in stool in abscess fluid from physician who previously resided in Panama. So we used the Lemon juice (Citrus at different concentration against Entamoeba histolytica to treat the amoebiasis disease. Entamoeba histolytica shows the variety of growth due to the effect of Lemon juice (Citrus. Lemon juice is ingredient and it has antiamoebic properties against Entamoeba histolytica a causative agent of amoebiasis.

  3. Helminth parasites of cats from the Vientiane Province, Laos, as indicators of the occurrence of causative agents of human parasitoses

    Directory of Open Access Journals (Sweden)

    Scholz T.

    2003-12-01

    Full Text Available A total of 55 domestic cats (Felis calus f. domestico and one wild (Bengal cat (Prionailurus bengalensis from the Vientiane Province, central Laos, were examined for helminth parasites with emphasis given to potential human parasites. The following species were found (parasites infective to man marked with an asterisk: Opisthorchis viverrini*, Haplorchis pumilio*,H. laichui*,H. yokogawai*, Stellantchasmus falcatus* (Digenea; Spirometra sp.*, Dipylidium caninum*, Taenia taeniaeformis (Cestoda; Capillariidae gen. sp., Toxocara canis*, T. cati*, Ancylostoma ceylanicum*, A. tubaeforme, Gnathostoma spinigerum*, Physaloptera preputials (Nematoda; and Oncicola sp. (Acanthocephala. This study demonstrated that examination of cats may provide useful data on the occurrence of helminths which are potential causative agents of human diseases.

  4. Infection of Parainfluenza type 3 (PI-3 as one of the causative agent of pneumonia in sheep and goats

    Directory of Open Access Journals (Sweden)

    Indrawati Sendow

    2002-03-01

    Full Text Available Serological survey was conducted to obtain the prevalence of Parainfluenza type 3 (PI-3 reactor as one of the causative agent of pneumonia in sheep and goats in abatoir at Jakarta and some small holder farms in Indonesia. Serological test using serum neutralization from 724 goat sera and 109 sheep sera indicated that only 1% of goats were serologically reactors and none of sheep sera had antibodies against PI-3 virus. Isolation of the virus from 56 bronchus and trachea swab and 345 lungs indicated that only one sampel from lung showed cythopathic effect (CPE in Madin Darby Bovine Kidney (MDBK cell lines identification of the virus using serum neutralization test indicated that the virus neutralized reference PI-3 antisera. The isolate came from one lung (7% of 24 that showed histopathologically pneumonia intertitialis that usually caused by viral infection.

  5. Multilocus sequence typing and evolutionary relationships among the causative agents of melioidosis and glanders, Burkholderia pseudomallei and Burkholderia mallei.

    Science.gov (United States)

    Godoy, Daniel; Randle, Gaynor; Simpson, Andrew J; Aanensen, David M; Pitt, Tyrone L; Kinoshita, Reimi; Spratt, Brian G

    2003-05-01

    A collection of 147 isolates of Burkholderia pseudomallei, B. mallei, and B. thailandensis was characterized by multilocus sequence typing (MLST). The 128 isolates of B. pseudomallei, the causative agent of melioidosis, were obtained from diverse geographic locations, from humans and animals with disease, and from the environment and were resolved into 71 sequence types. The utility of the MLST scheme for epidemiological investigations was established by analyzing isolates from captive marine mammals and birds and from humans in Hong Kong with melioidosis. MLST gave a level of resolution similar to that given by pulsed-field gel electrophoresis and identified the same three clones causing disease in animals, each of which was also associated with disease in humans. The average divergence between the alleles of B. thailandensis and B. pseudomallei was 3.2%, and there was no sharing of alleles between these species. Trees constructed from differences in the allelic profiles of the isolates and from the concatenated sequences of the seven loci showed that the B. pseudomallei isolates formed a cluster of closely related lineages that were fully resolved from the cluster of B. thailandensis isolates, confirming their separate species status. However, isolates of B. mallei, the causative agent of glanders, recovered from three continents over a 30-year period had identical allelic profiles, and the B. mallei isolates clustered within the B. pseudomallei group of isolates. Alleles at six of the seven loci in B. mallei were also present within B. pseudomallei isolates, and B. mallei is a clone of B. pseudomallei that, on population genetics grounds, should not be given separate species status.

  6. Hypercalcemia and calcinosis in Florida horses: implication of the shrub, Cestrum diurnum, as the causative agent.

    Science.gov (United States)

    Krook, L; Wasserman, R H; Shively, J N; Tashjian, A H; Brokken, T D; Morton, J F

    1975-01-01

    A chronic debilitating disease is described in Florida horses. There is progress weight loss and lameness of increasing severity. Plasma calcium is elevated to moderate or severe degree. Anatomical changes include dystrophic calcinosis of elastic tissues, viz. major arteries, tendons and ligaments. A generalized osteopetrosis is present and may be related to hypoparathyroidsim and hypercalcitoninism. The presence of Cestrum diurnum (day-blooming jessamine, day cestrum, wild jasmin) in areas accessible to affected animals, the observation that leaves of the plant were stripped in these areas, and the finding of a potent, active vitamin D-like substance in this plant constitute strong evidence that Cestrum diurnum is the agent causing the abnormalities of mineral metabolism.

  7. Inhibition of Xanthomonas fragariae, Causative Agent of Angular Leaf Spot of Strawberry, through Iron Deprivation

    Directory of Open Access Journals (Sweden)

    Peter Henry

    2016-10-01

    Full Text Available In commercial production settings, few options exist to prevent or treat angular leaf spot of strawberry, a disease of economic importance and caused by the bacterial pathogen Xanthomonas fragariae (Xfr. In the process of isolating and identifying Xfr bacteria from symptomatic plants, we observed growth inhibition of Xfr by bacterial isolates from the same leaf macerates. Identified as species of Pseudomonas and Rhizobium, these isolates were confirmed to suppress growth of Xfr in agar overlay plates and in microtiter plate cultures, as did our reference strain Pseudomonas putida KT2440. Screening of a transposon mutant library of KT2440 revealed that disruption of the biosynthetic pathway for the siderophore pyoverdine resulted in complete loss of Xfr antagonism, suggesting iron competition as a mode of action. Antagonism could be replicated on plate and in culture by addition of purified pyoverdine or by addition of the chelating agents tannic acid and dipyridyl, while supplementing the medium with iron negated the inhibitory effects of pyoverdine, tannic acid and dipyridyl. When co-inoculated with tannic acid onto strawberry plants, Xfr’s ability to cause foliar symptoms was greatly reduced, suggesting a possible opportunity for iron-based management of angular leaf spot. We discuss our findings in the context of ‘nutritional immunity’, the idea that plant hosts restrict pathogens access to iron, either directly, or indirectly through their associated microbiota.

  8. Growth of Ehrlichia canis, the causative agent of canine monocytic ehrlichiosis, in vector and non-vector ixodid tick cell lines.

    Science.gov (United States)

    Ferrolho, Joana; Simpson, Jennifer; Hawes, Philippa; Zweygarth, Erich; Bell-Sakyi, Lesley

    2016-06-01

    Canine monocytic ehrlichiosis is caused by Ehrlichia canis, a small gram-negative coccoid bacterium that infects circulating monocytes. The disease is transmitted by the brown dog tick Rhipicephalus sanguineus s.l. and is acknowledged as an important infectious disease of dogs and other members of the family Canidae worldwide. E. canis is routinely cultured in vitro in the canine monocyte-macrophage cell line DH82 and in non-vector Ixodes scapularis tick cell lines, but not in cells derived from its natural vector. Here we report infection and limited propagation of E. canis in the tick cell line RSE8 derived from the vector R. sanguineus s.l., and successful propagation through six passages in a cell line derived from the experimental vector Dermacentor variabilis. In addition, using bacteria semi-purified from I. scapularis cells we attempted to infect a panel of cell lines derived from non-vector species of the tick genera Amblyomma, Dermacentor, Hyalomma, Ixodes and Rhipicephalus with E. canis and, for comparison, the closely-related Ehrlichia ruminantium, causative agent of heartwater in ruminants. Amblyomma and non-vector Dermacentor spp. cell lines appeared refractory to infection with E. canis but supported growth of E. ruminantium, while some, but not all, cell lines derived from Hyalomma, Ixodes and Rhipicephalus spp. ticks supported growth of both pathogens. We also illustrated and compared the ultrastructural morphology of E. canis in DH82, RSE8 and I. scapularis IDE8 cells. This study confirms that E. canis, like E. ruminantium, is able to grow not only in cell lines derived from natural and experimental tick vectors but also in a wide range of other cell lines derived from tick species not known to transmit this pathogen.

  9. Reptile infection with Anaplasma phagocytophilum, the causative agent of granulocytic anaplasmosis.

    Science.gov (United States)

    Nieto, Nathan C; Foley, Janet E; Bettaso, Jamie; Lane, Robert S

    2009-10-01

    Granulocytic anaplasmosis (GA) is a potentially fatal tick-borne rickettsial disease that occurs sporadically in the far western United States. We evaluated the prevalence of Anaplasma phagocytophilum in multiple species of lizards and snakes from enzootic sites in northern California, described the infestation prevalence of its tick vector Ixodes pacificus on reptiles, and conducted an experimental challenge of western fence lizards (Sceloporus occidentalis) and Pacific gopher snakes (Pituophis catenifer) with A. phagocytophilum delivered via needle inoculation or tick bite. Both serologically and polymerase-chain reaction (PCR)-positive lizards (seroprevalence = 10.8%, PCR prevalence = 10.2%) and snakes (seroprevalence = 5.8%, PCR prevalence = 11.7%) were detected among wild-caught animals. A DNA sequence of the A. phagocytophilum groESL gene from a PCR-positive snake was 100% homologous to that of the human-derived A. phagocytophilum. Experimental attempts to infect naïve animals were unsuccessful for snakes (n = 2), but 1 of 12 lizards became infected for 1 wk only by tick bite. Xenodiagnostic I. pacificus larvae that fed on a PCR-positive lizard did not acquire or transmit rickettsiae. Our findings suggest that lizards and snakes are exposed to A. phagocytophilum by infected ticks, but that they do not serve as primary reservoir hosts of this rickettsia.

  10. A comparison of DNA extraction procedures for the detection of Mycobacterium ulcerans, the causative agent of Buruli ulcer, in clinical and environmental specimens

    DEFF Research Database (Denmark)

    Durnez, Lies; Stragier, Pieter; Roebben, Karen

    2008-01-01

    Mycobacterium ulcerans is the causative agent of Buruli ulcer, the third most common mycobacterial disease in humans after tuberculosis and leprosy. Although the disease is associated with aquatic ecosystems, cultivation of the bacillus from the environment is difficult to achieve. Therefore...

  11. Antifungal activity of essential oils of lemon balm, manuka and tansy to the causative agents of otomycosis

    Directory of Open Access Journals (Sweden)

    Jovanović Đorđe

    2016-01-01

    Full Text Available Introduction: Otomycosis is a superficial fungal infection of the external ear canal. One of the therapeutic approaches that became topical in treatment of otomycosis is the application of essential oils, which is shown to have different biological properties, including the antimicrobial effect. Aim: The objective of the research is to examine antimycotic effects of essential oils of lemon balm (Melissa officinalis, manuka (Leptospermum scoparium and tansy (Tanacetum vulgare on the causative agents of otomycosis. Materials and Methods: In this study, we investigated the sensitivity of 20 randomly selected strains of Candida spp. and Aspergillus spp. isolated from swabs taken from the external ear canal of patients with signs and symptoms of otitis externa. Antifungal activity of essential oils of lemon balm, manuka and tansy was tested by using the microdilution method by determining the value of the Minimum inhibitory concentration (MIC and Minimum fungicidal concentration (MFC. Results: MIC values of lemon balm were in the range of 0.39- 50 μl/ml, manuka of 0.39-50 μL/mL and tansy of 1.56-50 μL/mL. The MFC values were 2-4 times higher than the MIC values, except in the case of a strain of Aspergillus niger, which was tolerant of the lemon balm essential oil. Conclusion: The investigation has shown that essential oil activities of lemon balm, manuka and tansy to the strains of Candida spp. and Aspergillus spp, using the microdilution method, have antifungal effect.

  12. Clinicoepidemiologic pattern of cutaneous leishmaniasis and molecular characterization of its causative agent in Hajjah governorate, northwest of Yemen.

    Science.gov (United States)

    Mogalli, Nabil M; El Hossary, Shabaan S; Khatri, Mishri Lal; Mukred, Abdualdaim M; Kassem, Hala A; El Sawaf, Bahira M; Ramadan, Nadia F

    2016-11-01

    The clinicoepidemiologic profile of 143 cases (93 males and 50 females) with cutaneous leishmaniasis from 18 villages of Hajjah governorate, Yemen was studied. Dry-type lesions were seen in 98.6% and wet-type lesions in 1.4% of patients. Lesions were localized in all cases with different morphological patterns. Microscopic examination of Giemsa-stained slit smears revealed amastigotes in 74.1% of patients with dry-type lesions and 0% in patients with wet-type lesions. The burden of the parasites in the lesions was high indicating active transmission of the disease. Most cases were from villages with moderate altitude range (8001-1600m). All age groups were affected, but most cases were seen in ages from 5 to 15 years. Leishmania species identification was done for all cases by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The biopsic material was scraped from both Giemsa-stained and methanol-fixed smears. The molecular characterization of Leishmania species revealed Leishmania tropica as the causative agent of cutaneous leishmaniasis in Hajjah, Yemen. The risk factors associated with the transmission of the disease and recommendations for improving case detection were discussed.

  13. Identification of actinomycetes from plant rhizospheric soils with inhibitory activity against Colletotrichum spp., the causative agent of anthracnose disease.

    Science.gov (United States)

    Intra, Bungonsiri; Mungsuntisuk, Isada; Nihira, Takuya; Igarashi, Yasuhiro; Panbangred, Watanalai

    2011-04-01

    Colletotrichum is one of the most widespread and important genus of plant pathogenic fungi worldwide. Various species of Colletotrichum are the causative agents of anthracnose disease in plants, which is a severe problem to agricultural crops particularly in Thailand. These phytopathogens are usually controlled using chemicals; however, the use of these agents can lead to environmental pollution. Potential non-chemical control strategies for anthracnose disease include the use of bacteria capable of producing anti-fungal compounds such as actinomycetes spp., that comprise a large group of filamentous, Gram positive bacteria from soil. The aim of this study was to isolate actinomycetes capable of inhibiting the growth of Colletotrichum spp, and to analyze the diversity of actinomycetes from plant rhizospheric soil. A total of 304 actinomycetes were isolated and tested for their inhibitory activity against Colletotrichum gloeosporioides strains DoA d0762 and DoA c1060 and Colletotrichum capsici strain DoA c1511 which cause anthracnose disease as well as the non-pathogenic Saccharomyces cerevisiae strain IFO 10217. Most isolates (222 out of 304, 73.0%) were active against at least one indicator fungus or yeast. Fifty four (17.8%) were active against three anthracnose fungi and 17 (5.6%) could inhibit the growth of all three fungi and S. cerevisiae used in the test. Detailed analysis on 30 selected isolates from an orchard at Chanthaburi using the comparison of 16S rRNA gene sequences revealed that most of the isolates (87%) belong to the genus Streptomyces sp., while one each belongs to Saccharopolyspora (strain SB-2) and Nocardiopsis (strain CM-2) and two to Nocardia (strains BP-3 and LK-1). Strains LC-1, LC-4, JF-1, SC-1 and MG-1 exerted high inhibitory activity against all three anthracnose fungi and yeast. In addition, the organic solvent extracts prepared from these five strains inhibited conidial growth of the three indicator fungi. Preliminary analysis of crude

  14. Development and Evaluation of a Molecular Diagnostic Method for Rapid Detection of Histoplasma capsulatum var. farciminosum, the Causative Agent of Epizootic Lymphangitis, in Equine Clinical Samples

    OpenAIRE

    Scantlebury, C. E.; Pinchbeck, G.L.; Loughnane, P.; Aklilu, N.; Ashine, T.; Stringer, A. P.; Gordon, L.; Marshall, M; Christley, R.M.; McCarthy, A. J.

    2016-01-01

    Histoplasma capsulatum var. farciminosum, the causative agent of epizootic lymphangitis (EZL), is endemic in parts of Africa. Diagnosis based on clinical signs and microscopy lacks specificity and is a barrier to further understanding this neglected disease. Here, a nested PCR method targeting the internal transcribed spacer (ITS) region of the rRNA operon was validated for application to equine clinical samples. Twenty-nine horses with signs of EZL from different climatic regions of Ethiopia...

  15. The complete genome sequence of Yersinia pseudotuberculosis IP31758, the causative agent of Far East scarlet-like fever.

    Directory of Open Access Journals (Sweden)

    Mark Eppinger

    2007-08-01

    Full Text Available The first reported Far East scarlet-like fever (FESLF epidemic swept the Pacific coastal region of Russia in the late 1950s. Symptoms of the severe infection included erythematous skin rash and desquamation, exanthema, hyperhemic tongue, and a toxic shock syndrome. The term FESLF was coined for the infection because it shares clinical presentations with scarlet fever caused by group A streptococci. The causative agent was later identified as Yersinia pseudotuberculosis, although the range of morbidities was vastly different from classical pseudotuberculosis symptoms. To understand the origin and emergence of the peculiar clinical features of FESLF, we have sequenced the genome of the FESLF-causing strain Y. pseudotuberculosis IP31758 and compared it with that of another Y. pseudotuberculosis strain, IP32953, which causes classical gastrointestinal symptoms. The unique gene pool of Y pseudotuberculosis IP31758 accounts for more than 260 strain-specific genes and introduces individual physiological capabilities and virulence determinants, with a significant proportion horizontally acquired that likely originated from Enterobacteriaceae and other soil-dwelling bacteria that persist in the same ecological niche. The mobile genome pool includes two novel plasmids phylogenetically unrelated to all currently reported Yersinia plasmids. An icm/dot type IVB secretion system, shared only with the intracellular persisting pathogens of the order Legionellales, was found on the larger plasmid and could contribute to scarlatinoid fever symptoms in patients due to the introduction of immunomodulatory and immunosuppressive capabilities. We determined the common and unique traits resulting from genome evolution and speciation within the genus Yersinia and drew a more accurate species border between Y. pseudotuberculosis and Y. pestis. In contrast to the lack of genetic diversity observed in the evolutionary young descending Y. pestis lineage, the population

  16. Characterization of glycans in the developmental stages of Myxobolus cerebralis (Myxozoa), the causative agent of whirling disease.

    Science.gov (United States)

    Kaltner, H; Stippl, M; Knaus, M; El-Matbouli, M

    2007-11-01

    Glycans and sugar-binding molecules (lectins) form an interactive recognition system, which may enable parasitic organisms to adhere to host cells and migrate into target tissues. The aim of the present study was to analyse surface-associated glycans in the developmental stages of Myxobolus cerebralis (Hofer), the causative agent of whirling disease. A panel of biotin-labelled plant lectins was used to detect a broad spectrum of glycan motifs with high specificity. Binding sites were detected histochemically in the tissue sections of infected rainbow trout, Oncorhynchus mykiss (Walbaum), and infected Tubifex tubifex (Müller), and were characterized by light, fluorescence and transmission electron microscopy. With mannose-specific lectins [Lens culinaris agglutinin, Pisum sativum agglutinin, Canavalia ensiformis agglutinin (LCA, PSA, CanA)] mannose-containing glycans were detected in all the developmental stages and host tissues. No binding sites for galactose-specific lectins were present in M. cerebralis spores but reactivity with host tissues occurred. Diversity in glycans was detected by N-acetyl-D-galactosamine-specific lectins in sporoplasm cells of M. cerebralis and triactinomyxon spores. In the group of lectins with monosaccharide-specificity for N-acetyl-D-glucosamine (GlcNAc), the reactivity of Datura stramonium agglutinin (DSA), Lycopersicon esculentum agglutinin (LEA) and Solanum tuberosum agglutinin (STA) was restricted to polar capsules whereas Griffonia simplicifolia agglutinin II (GSA II) also bound to sporoplasm cells of stages in the fish host but not in those present in infected T. tubifex. Moreover, Triticum vulgaris (wheat germ) agglutinin (WGA) and succinylated WGA indicated the presence of N-acetyl-D-glucosamine polymers in polar capsules. No specificity for spores was observed concerning 'bisected'N-glycans and no reactivity in parasitic stages was observed with the fucose-binding lectin Ulex europaeus agglutinin (UEA) I, Sambucus nigra

  17. The In Vitro Antifungal Activity of Sudanese Medicinal Plants against Madurella mycetomatis, the Eumycetoma Major Causative Agent

    NARCIS (Netherlands)

    H. Elfadil (Hassabelrasoul); A.H. Fahal (Ahmed); W. Kloezen (Wendy); E.M. Ahmed (Elhadi M.); W.W.J. van de Sande (Wendy)

    2015-01-01

    textabstractEumycetoma is a debilitating chronic inflammatory fungal infection that exists worldwide but it is endemic in many tropical and subtropical regions. The major causative organism is the fungus Madurella mycetomatis. The current treatment of eumycetoma is suboptimal and characterized by lo

  18. The In Vitro Antifungal Activity of Sudanese Medicinal Plants against Madurella mycetomatis, the Eumycetoma Major Causative Agent

    NARCIS (Netherlands)

    H. Elfadil (Hassabelrasoul); A.H. Fahal (Ahmed); W. Kloezen (Wendy); E.M. Ahmed (Elhadi M.); W.W.J. van de Sande (Wendy)

    2015-01-01

    textabstractEumycetoma is a debilitating chronic inflammatory fungal infection that exists worldwide but it is endemic in many tropical and subtropical regions. The major causative organism is the fungus Madurella mycetomatis. The current treatment of eumycetoma is suboptimal and characterized by lo

  19. Representing Causation

    Science.gov (United States)

    Wolff, Phillip

    2007-01-01

    The dynamics model, which is based on L. Talmy's (1988) theory of force dynamics, characterizes causation as a pattern of forces and a position vector. In contrast to counterfactual and probabilistic models, the dynamics model naturally distinguishes between different cause-related concepts and explains the induction of causal relationships from…

  20. Sensitivities of major causative organisms isolated from patients with acute uncomplicated cystitis against various antibacterial agents: results of subanalysis based on the presence of menopause.

    Science.gov (United States)

    Matsumoto, Tetsuro; Hamasuna, Ryoichi; Ishikawa, Kiyohito; Takahashi, Satoshi; Yasuda, Mitsuru; Hayami, Hiroshi; Tanaka, Kazushi; Muratani, Tetsuro; Monden, Koichi; Arakawa, Soichi; Yamamoto, Shingo

    2012-08-01

    We investigated whether the presence of menopause influenced the species and distribution of causative bacteria isolated from patients with acute uncomplicated cystitis (the most common urinary tract infection), and we also investigated the sensitivity of the isolated species to antibacterial agents. Using multivariate analysis, we also investigated risk factors for infection with quinolone-resistant Escherichia coli, because its frequency has increased and it is now a clinical problem in Japan. Six hundred and thirty-four strains were isolated from 489 premenopausal patients (mean age 32.3 ± 10.1 years). Major causative bacteria detected were Escherichia coli (65.0 %), Enterococcus faecalis (12.0 %), Streptococcus agalactiae (5.5 %), and Klebsiella pneumoniae (1.6 %). From 501 postmenopausal patients (mean age 68.7 ± 10.29 years), 657 strains were isolated, and the major causative bacteria detected were E. coli (61.5 %), E. faecalis (13.7 %), K. pneumoniae (5.2 %), and S. agalactiae (4.0 %). The sensitivities to fluoroquinolones (FQs) and cephems of E. coli isolated from premenopausal patients were both ≥90 %, while the sensitivities to FQs of E. coli isolated from postmenopausal patients were about 5 % lower. In regard to infection with quinolone-resistant E. coli (minimal inhibitory concentration of levofloxacin [LVFX] ≥4 μg/mL), significant risk factors were observed in patients with more than two episodes of cystitis within a year (p = 0.0002), patients to whom antibacterial agents were used previously for this episode of cystitis (p = 0.0175), and patients who had a history of FQ administration within 1 month. Although the species and distribution of causative bacteria of acute uncomplicated cystitis were the same regardless of the presence of menopause, the sensitivities to FQs of E. coli detected in postmenopausal patients were significantly lower than those in the premenopausal women. The major risk factors for infection with quinolone-resistant E

  1. Potential causative agents of acute gastroenteritis in households with preschool children : prevalence, risk factors, clinical relevance and household transmission

    NARCIS (Netherlands)

    Heusinkveld, M.; Mughini-Gras, L.; Pijnacker, R.; Vennema, H.; Scholts, R.; van Huisstede-Vlaanderen, K. W.; Kortbeek, T.; Kooistra-Smid, M.; van Pelt, W.

    2016-01-01

    Acute gastroenteritis (AGE) morbidity remains high amongst preschool children, posing a significant societal burden. Empirical data on AGE-causing agents is needed to gauge their clinical relevance and identify agent-specific targets for control. We assessed the prevalence, risk factors and associat

  2. Potential causative agents of acute gastroenteritis in households with preschool children : prevalence, risk factors, clinical relevance and household transmission

    NARCIS (Netherlands)

    Heusinkveld, M.; Mughini-Gras, L.; Pijnacker, R.; Vennema, H.; Scholts, R.; van Huisstede-Vlaanderen, K. W.; Kortbeek, T.; Kooistra-Smid, M.; van Pelt, W.

    2016-01-01

    Acute gastroenteritis (AGE) morbidity remains high amongst preschool children, posing a significant societal burden. Empirical data on AGE-causing agents is needed to gauge their clinical relevance and identify agent-specific targets for control. We assessed the prevalence, risk factors and

  3. Potential causative agents of acute gastroenteritis in households with preschool children : prevalence, risk factors, clinical relevance and household transmission

    NARCIS (Netherlands)

    Heusinkveld, M.; Mughini-Gras, L.; Pijnacker, R.; Vennema, H.; Scholts, R.; van Huisstede-Vlaanderen, K. W.; Kortbeek, T.; Kooistra-Smid, M.; van Pelt, W.

    2016-01-01

    Acute gastroenteritis (AGE) morbidity remains high amongst preschool children, posing a significant societal burden. Empirical data on AGE-causing agents is needed to gauge their clinical relevance and identify agent-specific targets for control. We assessed the prevalence, risk factors and associat

  4. Cutaneous adverse drug reactions: clinical pattern and causative agents--a 6 year series from Chandigarh, India.

    Directory of Open Access Journals (Sweden)

    Sharma V

    2001-04-01

    Full Text Available AIM: To study the different clinical spectrum of cutaneous adverse drug reactions (ADR and to determine the causative drugs. MATERIALS & METHODS: A prospective, hospital based study was carried out over a period of 6 years recording various cutaneous ADR. RESULTS: A total of 500 patients with cutaneous ADR were enrolled in the study. The most common types of cutaneous ADR patterns were maculopapular rash (34.6%, fixed drug eruption (FDE (30% and urticaria (14%. The drugs most often incriminated for the various cutaneous ADR were antimicrobials (42.6%, anticonvulsants (22.2% and NSAIDs (18%. Anticonvulsants were implicated in 41.6% of maculopapular rashes. Sulfonamides accounted for 43.3% and NSAIDs for 30.7% of FDE. Urticaria was caused mainly by NSAIDs(24.3% and penicillins(20%. Anticonvulsants were responsible for 43.8% of life-threatening toxic epidermal necrolysis and Stevens Johnson syndrome. CONCLUSIONS: The clinical pattern and drugs causing cutaneous ADR are similar to those observed in other countries except for minor variations. Cutaneous ADR patterns and the drugs causing various reactions are changing every year, which may be due to the emergence of newer molecules and changing trends in the use of drugs.

  5. Identification of Clostridium tyrobutyricum as the causative agent of late blowing in cheese by species-specific PCR amplification.

    Science.gov (United States)

    Klijn, N; Nieuwenhof, F F; Hoolwerf, J D; van der Waals, C B; Weerkamp, A H

    1995-08-01

    Butyric acid fermentation, the late-blowing defect in cheese, caused by the outgrowth of clostridial spores present in raw milk, can create considerable loss of product, especially in the production of semihard cheeses like Gouda cheese, but also in grana and Gruyère cheeses. To demonstrate the causative relationship between Clostridium tyrobutyricum and late blowing in cheese, many cheesemaking experiments were performed to provoke this defect by using spores from several strains of the major dairy-related clostridia. A method of PCR amplification of a part of the 16S rRNA gene in combination with hybridization with species-specific DNA probes was developed to allow the specific detection of clostridial sequences in DNAs extracted from cheeses. The sensitivity was increased by using nested PCR. Late blowing was provoked in experimental cheeses with 28 of the 32 C. tyrobutyricum strains tested, whereas experimental cheeses made with spores from C. beijerinckii, C. butyricum, and C. sporogenes showed no signs of butyric acid fermentation. In all experimental and commercial cheeses with obvious signs of late blowing, DNA from C. tyrobutyricum was detected; in some cheeses, signals for C. beijerinckii were also found. It was concluded that only C. tyrobutyricum strains are able to cause butyric acid fermentation in cheese.

  6. Loop-mediated isothermal amplification as an emerging technology for detection of Yersinia ruckeri the causative agent of enteric red mouth disease in fish

    Directory of Open Access Journals (Sweden)

    Soliman Hatem

    2008-08-01

    Full Text Available Abstract Background Enteric Redmouth (ERM disease also known as Yersiniosis is a contagious disease affecting salmonids, mainly rainbow trout. The causative agent is the gram-negative bacterium Yersinia ruckeri. The disease can be diagnosed by isolation and identification of the causative agent, or detection of the Pathogen using fluorescent antibody tests, ELISA and PCR assays. These diagnostic methods are laborious, time consuming and need well trained personnel. Results A loop-mediated isothermal amplification (LAMP assay was developed and evaluated for detection of Y. ruckeri the etiological agent of enteric red mouth (ERM disease in salmonids. The assay was optimised to amplify the yruI/yruR gene, which encodes Y. ruckeri quorum sensing system, in the presence of a specific primer set and Bst DNA polymerase at an isothermal temperature of 63°C for one hour. Amplification products were detected by visual inspection, agarose gel electrophoresis and by real-time monitoring of turbidity resulted by formation of LAMP amplicons. Digestion with HphI restriction enzyme demonstrated that the amplified product was unique. The specificity of the assay was verified by the absence of amplification products when tested against related bacteria. The assay had 10-fold higher sensitivity compared with conventional PCR and successfully detected Y. ruckeri not only in pure bacterial culture but also in tissue homogenates of infected fish. Conclusion The ERM-LAMP assay represents a practical alternative to the microbiological approach for rapid, sensitive and specific detection of Y. ruckeri in fish farms. The assay is carried out in one hour and needs only a heating block or water bath as laboratory furniture. The advantages of the ERM-LAMP assay make it a promising tool for molecular detection of enteric red mouth disease in fish farms.

  7. Ludwik Fleck and the causative agent of syphilis: sociology or pathology of science? A rejoider to Jean Lindenmann

    NARCIS (Netherlands)

    Belt, van den H.

    2002-01-01

    In 1905 two different microbes were proposed to fill the vacant role of etiologic agent for syphilis, one, the Cytorrhyctes luis, by John Siegel, the other, Spirochaeta pallida, by Fritz Schaudinn. After gathering and reviewing the evidence the majority of medical scientists decided in favor of

  8. Causative agent distribution and antibiotic therapy assessment among adult patients with community acquired pneumonia in Chinese urban population

    Directory of Open Access Journals (Sweden)

    Liu Yong

    2009-03-01

    Full Text Available Abstract Background Knowledge of predominant microbial patterns in community-acquired pneumonia (CAP constitutes the basis for initial decisions about empirical antimicrobial treatment, so a prospective study was performed during 2003–2004 among CAP of adult Chinese urban populations. Methods Qualified patients were enrolled and screened for bacterial, atypical, and viral pathogens by sputum and/or blood culturing, and by antibody seroconversion test. Antibiotic treatment and patient outcome were also assessed. Results Non-viral pathogens were found in 324/610 (53.1% patients among whom M. pneumoniae was the most prevalent (126/610, 20.7%. Atypical pathogens were identified in 62/195 (31.8% patients carrying bacterial pathogens. Respiratory viruses were identified in 35 (19% of 184 randomly selected patients with adenovirus being the most common (16/184, 8.7%. The nonsusceptibility of S. pneumoniae to penicillin and azithromycin was 22.2% (Resistance (R: 3.2%, Intermediate (I: 19.0% and 79.4% (R: 79.4%, I: 0%, respectively. Of patients (312 from whom causative pathogens were identified and antibiotic treatments were recorded, clinical cure rate with β-lactam antibiotics alone and with combination of a β-lactam plus a macrolide or with fluoroquinolones was 63.7% (79/124 and 67%(126/188, respectively. For patients having mixed M. pneumoniae and/or C. pneumoniae infections, a better cure rate was observed with regimens that are active against atypical pathogens (e.g. a β-lactam plus a macrolide, or a fluoroquinolone than with β-lactam alone (75.8% vs. 42.9%, p = 0.045. Conclusion In Chinese adult CAP patients, M. pneumoniae was the most prevalent with mixed infections containing atypical pathogens being frequently observed. With S. pneumoniae, the prevalence of macrolide resistance was high and penicillin resistance low compared with data reported in other regions.

  9. The In Vitro Antifungal Activity of Sudanese Medicinal Plants against Madurella mycetomatis, the Eumycetoma Major Causative Agent

    Science.gov (United States)

    Elfadil, Hassabelrasoul; Fahal, Ahmed; Kloezen, Wendy; Ahmed, Elhadi M.; van de Sande, Wendy

    2015-01-01

    Eumycetoma is a debilitating chronic inflammatory fungal infection that exists worldwide but it is endemic in many tropical and subtropical regions. The major causative organism is the fungus Madurella mycetomatis. The current treatment of eumycetoma is suboptimal and characterized by low cure rate and high recurrence rates. Hence, an alternative therapy is needed to address this. Here we determined the antifungal activity of seven Sudanese medicinal plant species against Madurella mycetomatis. Of these, only three species; Boswellia papyrifera, Acacia nubica and Nigella sativa, showed some antifungal activity against M. mycetomatis and were further studied. Crude methanol, hexane and defatted methanol extracts of these species were tested for their antifungal activity. B. papyrifera had the highest antifungal activity (MIC50 of 1 ug/ml) and it was further fractionated. The crude methanol and the soluble ethyl acetate fractions of B. papyrifera showed some antifungal activity. The Gas-Liquid-Chromatography hybrid Mass-Spectrophotometer analysis of these two fractions showed the existence of beta-amyrin, beta-amyrone, beta-Sitosterol and stigmatriene. Stigmatriene had the best antifungal activity, compared to other three phytoconstituents, with an MIC-50 of 32 μg/ml. Although the antifungal activity of the identified phytoconstituents was only limited, the antifungal activity of the complete extracts is more promising, indicating synergism. Furthermore these plant extracts are also known to have anti-inflammatory activity and can stimulate wound-healing; characteristics which might also be of great value in the development of novel therapeutic drugs for this chronic inflammatory disease. Therefore further exploration of these plant species in the treatment of mycetoma is encouraging. PMID:25768115

  10. The in vitro antifungal activity of sudanese medicinal plants against Madurella mycetomatis, the eumycetoma major causative agent.

    Directory of Open Access Journals (Sweden)

    Hassabelrasoul Elfadil

    2015-03-01

    Full Text Available Eumycetoma is a debilitating chronic inflammatory fungal infection that exists worldwide but it is endemic in many tropical and subtropical regions. The major causative organism is the fungus Madurella mycetomatis. The current treatment of eumycetoma is suboptimal and characterized by low cure rate and high recurrence rates. Hence, an alternative therapy is needed to address this. Here we determined the antifungal activity of seven Sudanese medicinal plant species against Madurella mycetomatis. Of these, only three species; Boswellia papyrifera, Acacia nubica and Nigella sativa, showed some antifungal activity against M. mycetomatis and were further studied. Crude methanol, hexane and defatted methanol extracts of these species were tested for their antifungal activity. B. papyrifera had the highest antifungal activity (MIC50 of 1 ug/ml and it was further fractionated. The crude methanol and the soluble ethyl acetate fractions of B. papyrifera showed some antifungal activity. The Gas-Liquid-Chromatography hybrid Mass-Spectrophotometer analysis of these two fractions showed the existence of beta-amyrin, beta-amyrone, beta-Sitosterol and stigmatriene. Stigmatriene had the best antifungal activity, compared to other three phytoconstituents, with an MIC-50 of 32 μg/ml. Although the antifungal activity of the identified phytoconstituents was only limited, the antifungal activity of the complete extracts is more promising, indicating synergism. Furthermore these plant extracts are also known to have anti-inflammatory activity and can stimulate wound-healing; characteristics which might also be of great value in the development of novel therapeutic drugs for this chronic inflammatory disease. Therefore further exploration of these plant species in the treatment of mycetoma is encouraging.

  11. The in vitro antifungal activity of sudanese medicinal plants against Madurella mycetomatis, the eumycetoma major causative agent.

    Science.gov (United States)

    Elfadil, Hassabelrasoul; Fahal, Ahmed; Kloezen, Wendy; Ahmed, Elhadi M; van de Sande, Wendy

    2015-03-01

    Eumycetoma is a debilitating chronic inflammatory fungal infection that exists worldwide but it is endemic in many tropical and subtropical regions. The major causative organism is the fungus Madurella mycetomatis. The current treatment of eumycetoma is suboptimal and characterized by low cure rate and high recurrence rates. Hence, an alternative therapy is needed to address this. Here we determined the antifungal activity of seven Sudanese medicinal plant species against Madurella mycetomatis. Of these, only three species; Boswellia papyrifera, Acacia nubica and Nigella sativa, showed some antifungal activity against M. mycetomatis and were further studied. Crude methanol, hexane and defatted methanol extracts of these species were tested for their antifungal activity. B. papyrifera had the highest antifungal activity (MIC50 of 1 ug/ml) and it was further fractionated. The crude methanol and the soluble ethyl acetate fractions of B. papyrifera showed some antifungal activity. The Gas-Liquid-Chromatography hybrid Mass-Spectrophotometer analysis of these two fractions showed the existence of beta-amyrin, beta-amyrone, beta-Sitosterol and stigmatriene. Stigmatriene had the best antifungal activity, compared to other three phytoconstituents, with an MIC-50 of 32 μg/ml. Although the antifungal activity of the identified phytoconstituents was only limited, the antifungal activity of the complete extracts is more promising, indicating synergism. Furthermore these plant extracts are also known to have anti-inflammatory activity and can stimulate wound-healing; characteristics which might also be of great value in the development of novel therapeutic drugs for this chronic inflammatory disease. Therefore further exploration of these plant species in the treatment of mycetoma is encouraging.

  12. In vitro antibiotic susceptibilities of Burkholderia mallei (causative agent of glanders) determined by broth microdilution and E-test.

    Science.gov (United States)

    Heine, H S; England, M J; Waag, D M; Byrne, W R

    2001-07-01

    In vitro susceptibilities to 28 antibiotics were determined for 11 strains of Burkholderia mallei by the broth microdilution method. The B. mallei strains demonstrated susceptibility to aminoglycosides, macrolides, quinolones, doxycycline, piperacillin, ceftazidime, and imipenem. For comparison and evaluation, 17 antibiotic susceptibilities were also determined by the E-test. E-test values were always lower than the broth dilution values. Establishing and comparing antibiotic susceptibilities of specific B. mallei strains will provide reference information for assessing new antibiotic agents.

  13. In vitro susceptibility of Haemophilus equigenitalis, the causative organism of contagious equine metritis 1977, to antimicrobial agents.

    OpenAIRE

    DABERNAT, H.J.; Delmas, C F; Tainturier, D J; Lareng, M B

    1980-01-01

    The in vitro susceptibility of recent clinical isolates of Haemophilus equigenitalis to various antimicrobial agents was determined by the disk diffusion test and the World Health Organization-International Collaborative Study agar dilution procedure. Ampicillin and tetracycline were the most active drugs. All strains were susceptible to beta-lactam antibiotics, chloramphenicol, trimethoprim-sulfamethoxazole, nalidixic acid, nitrofurantoin (Furadantin), and bacitracin. All but two strains wer...

  14. The reliability of serogroup determination in the detection of Escherichia coli as a causative agent of sporadic and epidemic occurrence of enterocolitis

    Directory of Open Access Journals (Sweden)

    Stojanović Valentina

    2002-01-01

    Full Text Available The purpose of this study was to determine the presence of virulence factors (heat-labile, heat-stable enterotoxin, verotoxin, invasiveness, localized, aggregative and diffuse adherence among E. coli strains isolated from sporadic cases and outbreaks of enterocolitis, which belonged to serogroups characteristic for enteropathogenic E. coli. Serogroup was determined in 57.2% of 622 strains isolated from sporadic cases, and among them virulence factors were detected in 23.6%. Serogroup was also determined in 73.3% of 90 outbreaks isolates tested and virulence factors were detected in 97% of them. The detection rate of virulence factors rarely exceeded 50% among strains belonging to any of serogroup that was determined. The obtained data suggested that the identification of E. coli as a causative agent of enterocolitis by serogroup determination was a reliable method in outbreaks, but not in sporadic cases of this disease.

  15. Genomic Patterns of Pathogen Evolution Revealed by Comparison of Burkholderia pseudomallei, the Causative Agent of Melioidosis, to Avirulent Burkholderia thailandensis

    Science.gov (United States)

    2006-05-26

    structure derived using Structural Classification of Proteins ( SCOP ) defined structural folds. We used SUPERFAMILY analysis to classify and compare...produced 3706 Bt sequences with 721 unique SCOP superfamilies and 3645 Bp sequences with 705 unique SCOP superfamilies. The top 20 structural families...electrophoresis. SUPERFAMILY assignment SUPERFAMILY (release 1.69) is a library of HMM models based on SCOP and contains 1539 known structural superfamilies [33

  16. Detection and molecular characterization of canine babesiosis causative agent Babesia canis in the naturally infected dog in Lithuania.

    Science.gov (United States)

    Paulauskas, Algimantas; Radzijevskaja, Jana; Karvelienė, Birutė; Grigonis, Aidas; Aleksandravičienė, Asta; Zamokas, Gintaras; Babickaitė, Lina; Sabūnas, Vytautas; Petkevičius, Saulius

    2014-10-15

    Canine babesiosis caused by Babesia canis is an emerging infectious disease in Europe. Although previously uncommon, canine babesiosis has become quite frequent in Lithuania during the past decade. In the last few years an increasing number of cases with a wide variety of clinical signs have been recorded throughout the country. In Lithuania the identification of the disease agent in veterinarian clinics is based on a microscopic analysis of size and morphology. To date, no data on the genetic characterization of Babesia species in dogs have been documented for Lithuania. A total of 123 blood samples from dogs showing clinical signs of babesiosis on the basis of veterinary examination were tested for the presence of babesial parasites. Babesia isolated from dogs were detected and characterized by nested-PCR and sequence analysis of a fragment of the 18S rRNA gene. Babesia parasites were detected in blood smears of 94 dogs (76.4%). The molecular analysis revealed the presence of B. canis in 108 dogs (87.8%). Two genotypes of B. canis were distinguished on the basis on two nucleotide (GA → AG) substitutions observed in 18S rRNA gene sequences. The results of the present study provide knowledge of the distribution of B. canis genotypes in dogs in Lithuania, and show the necessity to use a molecular analysis for an accurate diagnosis of canine babesiosis.

  17. Molecular detection and investigation of the presence of dirofilariosis causative agent in dogs on the territory of Belgrade

    Directory of Open Access Journals (Sweden)

    Davitkov Dajana

    2016-01-01

    Full Text Available Dirofilariosis in dogs is a parasitic disease caused by the strains Dirofilaria immitis and D. Repens. Dirofilaria immitis parasitizes in the right side of the heart and pulmonary artery, causing considerable functional impairment of the heart, while adult forms of D. repens mostly parasitize in subcutaneous tissue causing minor skin damage. In this investigation, during the period from May to November 2015, 60 dogs of different race from the territory of Belgrade were examined. Ater the clinical examination, the blood was sampled for microfilariae detection by Knott test, as well as for molecular detection of the agent. Main clinical signs were: fatigue during exersise, shortness of breath and dry cough, anorexia, rapid heartbeat and skin changes. Microfilariae were detected in 22 dogs (37% by modified Knott test. By molecular genetic method there was determined the prevalence of D. immitis 42%, and D. repens 22%. In this investigation 7 dogs were negative on Knott test, but by PCR method they showed a positive reaction on the presence of species of the genus Dirofilaria. On the basis of the obtained results, the application of molecular-genetic methods is justified in accurate and reliable species identification of Dirofilaria genus.

  18. Clinical signs, seasonal occurrence and causative agents of canine babesiosis in France: results of a multiregional study.

    Science.gov (United States)

    René-Martellet, M; Chêne, J; Chabanne, L; Chalvet-Monfray, K; Bourdoiseau, G

    2013-10-18

    Canine babesiosis (or piroplasmosis) is an emerging tick-borne disease caused by intraerythrocytic protozoa of the genera Babesia and Theileria. In dogs, infection by these parasites usually induces a haemolytic syndrome that can be fatal when complicated. Canine babesiosis prevalence is high in France, with Babesia canis thought to be the main etiological agent of the disease. This article presents the results of a multiregional prospective longitudinal survey on canine babesiosis conducted in France from October 2006 to December 2007. A total of 836 cases were reported by veterinarians using a multiple choice questionnaire and blood samples from 70 dogs were analyzed using PCR-RFLP to identify species responsible for canine babesiosis cases across the country. The main clinical signs reported were lethargy (98%), anorexia (98%) and hyperthermia ≥ 39 °C (80%) followed by pale mucous membranes (54%), modification of urine aspect (45%) and splenomegaly (33%). The dog population at risk was mainly represented by young dogs living in rural areas. Twenty-five out of the 70 blood samples (36%) tested by diagnostic PCR were found to contain Babesia/Theileria genus-specific DNA and all had profiles similar to that of Babesia canis genomic DNA after restriction fragment length polymorphism analyses. The survey results provide a reference for further molecular studies to assess the species and vectors involved in the transmission of the disease in France and across the Mediterranean basin. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Inhibition by Dications of in vitro growth of Leishmania major and Leishmania tropica: causative agents of old world cutaneous leishmaniasis.

    Science.gov (United States)

    Rosypal, Alexa C; Werbovetz, Karl A; Salem, Manar; Stephens, Chad E; Kumar, Arvind; Boykin, David W; Hall, James E; Tidwell, Richard R

    2008-06-01

    Old World cutaneous leishmaniasis is caused by infection with Leishmania major and Leishmania tropica. Pentamidine and related dications exhibit broad spectrum antiprotozoal activity. Based on the previously reported efficacy of these compounds against related organisms, 18 structural analogs of pentamidine were evaluated for in vitro antileishmanial activity, using pentamidine as the standard reference drug for comparison. Furan analogs and reversed amidine compounds were examined for activity against L. major and L. tropica promastigotes. The most active compounds against both Leishmania species were in the reversed amidine series. DB745 and DB746 exhibited the highest activity against L. major and DB745 was the most active compound against L. tropica. Both of these compounds exhibited 50% inhibitory concentrations (IC50) below 1 nM for L. major. Ten reversed amidines were also tested for their ability to inhibit growth in an axenic amastigote model. Nine of 10 reversed amidine analogs were active at concentrations below 1 nM. These results justify further study of dicationic compounds as potential new agents for treating cutaneous leishmaniasis.

  20. Screening and Functional Analysis of the Peroxiredoxin Specifically Expressed in Bursaphelenchus xylophilus—The Causative Agent of Pine Wilt Disease

    Directory of Open Access Journals (Sweden)

    Han-Yu Fu

    2014-06-01

    Full Text Available The pine wood nematode, Bursaphelenchus xylophilus, is the causal agent of pine wilt disease. Accurately differentiating B. xylophilus from other nematodes species, especially its related species B. mucronatus, is important for pine wood nematode detection. Thus, we attempted to identify a specific protein in the pine wood nematode using proteomics technology. Here, we compared the proteomes of B. xylophilus and B. mucronatus using Two-dimensional gel electrophoresis (2-DE and matrix-assisted laser desorption/ionization -time-of-flight/time-of-flight (MALDI-TOF/TOF-MS technologies. In total, 15 highly expressed proteins were identified in B. xylophilus compared with B. mucronatus. Subsequently, the specificity of the proteins identified was confirmed by PCR using the genomic DNA of other nematode species. Finally, a gene encoding a specific protein (Bx-Prx was obtained. This gene was cloned and expressed in E. coli. The in situ hybridisation pattern of Bx-Prx showed that it was expressed strongly in the tail of B. xylophilus. RNAi was used to assess the function of Bx-Prx, the results indicated that the gene was associated with the reproduction and pathogenicity of B. xylophilus. This discovery provides fundamental information for identifying B. xylophilus via a molecular approach. Moreover, the purified recombinant protein has potential as a candidate diagnostic antigen of pine wilt disease, which may lead to a new immunological detection method for the pine wood nematode.

  1. Anion inhibition studies of the α-carbonic anhydrase from the protozoan pathogen Trypanosoma cruzi, the causative agent of Chagas disease.

    Science.gov (United States)

    Pan, Peiwen; Vermelho, Alane Beatriz; Scozzafava, Andrea; Parkkila, Seppo; Capasso, Clemente; Supuran, Claudiu T

    2013-08-01

    The protozoan pathogen Trypanosoma cruzi, the causative agent of Chagas disease, encodes an α-class carbonic anhydrase (CA, EC 4.2.1.1), TcCA, which was recently shown to be crucial for its life cycle. Thiols, a class of strong TcCA inhibitors, were also shown to block the growth of the pathogen in vitro. Here we report the inhibition of TcCA by inorganic and complex anions and other molecules interacting with zinc proteins, such as sulfamide, sulfamic acid, phenylboronic/arsonic acids. TcCA was inhibited in the low micromolar range by iodide, cyanate, thiocyanate, hydrogensulfide and trithiocarbonate (KIs in the range of 44-93 μM), but the best inhibitor was diethyldithiocarbamate (KI=5 μM). Sulfamide showed an inhibition constant of 120 μM, but sulfamic acid was much less effective (KI of 10.6 mM). The discovery of diethyldithiocarbamate as a low micromolar TcCA inhibitor may be useful to detect leads for developing anti-Trypanosoma agents with a diverse mechanism of action compared to clinically used drugs (benznidazole, nifurtimox) for which significant resistance emerged.

  2. Cobalt Derivatives as Promising Therapeutic Agents

    Science.gov (United States)

    Heffern, Marie C.; Yamamoto, Natsuho; Holbrook, Robert J.; Eckermann, Amanda L.; Meade, Thomas J.

    2013-01-01

    Inorganic complexes are versatile platforms for the development of potent and selective pharmaceutical agents. Cobalt possesses a diverse array of properties that can be manipulated to yield promising drug candidates. Investigations into the mechanism of cobalt therapeutic agents can provide valuable insight into the physicochemical properties that can be harnessed for drug development. This review presents examples of bioactive cobalt complexes with special attention to their mechanisms of action. Specifically, cobalt complexes that elicit biological effects through protein inhibition, modification of drug activity, and bioreductive activation are discussed. Insights gained from these examples reveal features of cobalt that can be rationally tuned to produce therapeutics with high specificity and improved efficacy for the biomolecule or pathway of interest. PMID:23270779

  3. Synthesis of metronidazole derivatives as antigiardiasis agents

    Directory of Open Access Journals (Sweden)

    Khabnadideh S.

    2007-04-01

    Full Text Available Metronidazole (MTZ and its derivatives have been extensively used to treat infections caused by protozoa and anaerobic bacteria. In this investigation several novel imidazole and nitroimidazol derivatives namely: 2-(1H-1-imidazolyl-1-phenyl-1-ethanol 1a, 2-(2-methyl-1H-1-imidazolyl-1-phenyl-1-ethanol 1b, 2-(2-methyl-4-nitro-1H-1-imidazolyl-1-phenyl-1-ethanol 1c, 2-(1H-1-imidazolyl-1-cyclohexanol 2d and 2-(2-methyl-4-nitro-1H-1-imidazolyl-1-cyclohexanol 2e were prepared by the reaction of the corresponding imidazoles with styrene oxide or cyclohexene oxide respectively and their biological activity against Giardia lamblia cyst in compareison with MTZ were determined by flotation technique based on Bingham method. These compounds were less active than metronidazole but showed significant antigiardiasis activity.

  4. 4'-Acetamidochalcone Derivatives as Potential Antinociceptive Agents

    Directory of Open Access Journals (Sweden)

    Valdir Cechinel-Filho

    2007-04-01

    Full Text Available Nine acetamidochalcones were synthesized and evaluated as antinociceptive agents using the mice writhing test. Given intraperitoneally all the compounds were more effective than the two reference analgesic drugs (acetylsalicylic acid and acetaminophen used for comparison. N-{4-[(2E-3-(4-nitrophenylprop-2-enoyl]phenyl}acetamide (6 was the most effective compound and was therefore selected for more detailed studies. It caused dose-related inhibition in the writhing test, being about 32 to 34-fold more potent than the standard drugs. It was also effective in the second phase of the formalin test and the capsaicin test. These acetamidochalcones, especially compound 6, might be further used as models to obtain new and more potent analgesic drugs.

  5. Chalcone derivatives as potential antifungal agents: Synthesis, and antifungal activity

    Directory of Open Access Journals (Sweden)

    Deepa Gupta

    2015-01-01

    Full Text Available Much research has been carried out with the aim to discover the therapeutic values of chalcone derivatives. Chalcones possess wide range of pharmacological activity such as antibacterial, antimalarial, antiprotozoal, antitubercular, anticancer, and antifungal agents etc. The presence of reactive α,β-unsaturated keto group in chalcones is found to be responsible for their biological activity. The rapid developments of resistance to antifungal agents, led to design, and synthesize the new antifungal agents. The derivatives of chalcones were prepared using Claisen-Schmidt condensation scheme with appropriate tetralone and aldehyde derivatives. Ten derivatives were synthesized and were biologically screened for antifungal activity. The newly synthesized derivatives of chalcone showed antifungal activity against fungal species, Microsporum gypseum. The results so obtained were superior or comparable to ketoconazole. It was observed that none of the compounds tested showed positive results for fungi Candida albicans nor against fungi Aspergillus niger. Chalcone derivatives showed inhibitory effect against M. gypseum species of fungus. It was found that among the chalcone derivatives so synthesized, two of them, that is, 4-chloro derivative, and unsubstituted derivative of chalcone showed antifungal activity superior to ketoconazole. Thus, these can be the potential new molecule as antifungal agent.

  6. Variability in triactinomyxon production from Tubifex tubifex populations from the same mitochondrial DNA lineage infected with Myxobolus cerebralis, the causative agent of whirling disease in salmonids

    Science.gov (United States)

    Rasmussen, C.; Zickovich, J.; Winton, J.R.; Kerans, B.L.

    2008-01-01

    Myxobolus cerebralis, the causative agent of whirling disease, infects both salmonid fish and an aquatic oligochaete, Tubifex tubifex. Although M. cerebralis has been detected in river drainages throughout the United States, disease severity among wild fish populations has been highly variable. Tubifex tubifex populations have been genetically characterized using sequences from the 16S mitochondrial DNA (mtDNA) gene, the 18S ribosomal RNA gene, the internal transcribed spacer region 1 (ITS1), and randomly amplified polymorphic DNA (RAPD). Our earlier work indicated that large differences in compatibility between the parasite and populations of T. tubifex may play a substantial role in the distribution of whirling disease and resulting mortality in different watersheds. In the present study, we examined 4 laboratory populations of T. tubifex belonging to 16S mtDNA lineage III and 1 population belonging to 16S mtDNA lineage I for triactinomyxon (TAM) production after infection with M. cerebralis myxospores. All 4 16S mtDNA lineage III populations produced TAMs, but statistically significant differences in TAM production were observed. Most individuals in the 16S mtDNA lineage III-infected populations produced TAMs. The 16S mtDNA lineage I population produced few TAMs. Further genetic characterization of the 16S mtDNA lineage III populations with RAPD markers indicated that populations producing similar levels of TAMs had more genetic similarity. ?? American Society of Parasitologists 2008.

  7. Soluble material secreted from Penicillium chrysogenum isolate exhibits antifungal activity against Cryphonectria parasitica- the causative agent of the American Chestnut Blight

    Science.gov (United States)

    Florjanczyk, Aleksandr; Barnes, Rebecca; Kenney, Adam; Horzempa, Joseph

    2016-01-01

    The American chestnut (Castanea dentata) was once the dominant canopy tree along the eastern region of the United States. Cryphonectria parasitica, the causative agent of chestnut blight, was introduced from Asia in the early 1900's, and obliterated the chestnut population within 50 years. We sought to identify environmental microbes capable of producing factors that were fungicidal or inhibited growth of C. parasitica in the hopes developing a biological control of chestnut blight. We isolated a filamentous fungus that significantly inhibited the growth of C. parasitica upon co-cultivation. Extracellular fractions of this fungal isolate prevented C. parasitica growth, indicating that a potential fungicide was produced by the novel isolate. Sequence analysis of 18S rRNA identified this inhibitory fungus as Penicillium chrysogenum. Furthermore, these extracellular fractions were tested as treatments for blight in vivo using chestnut saplings. Scarred saplings that were treated with the P. chrysogenum extracellular fractions healed subjectively better than those without treatment when inoculated with C. parasitica. These data suggest that material secreted by P. chrysogenum could be used as a treatment for the American chestnut blight. This work may assist the reclamation of the American chestnut in association with breeding programs and blight attenuation. Specifically, treatment of small groves under the right conditions may allow them to remain blight free. Future work will explore the mechanism of action and specific target of the extracellular fraction. PMID:27274909

  8. Molecular identification of the causative agent of human strongyloidiasis acquired in Tanzania: dispersal and diversity of Strongyloides spp. and their hosts.

    Science.gov (United States)

    Hasegawa, Hideo; Sato, Hiroshi; Fujita, Shiho; Nguema, Pierre Philippe Mbehang; Nobusue, Kenichi; Miyagi, Kei; Kooriyama, Takanori; Takenoshita, Yuji; Noda, Shohei; Sato, Akiko; Morimoto, Azusa; Ikeda, Yatsukaho; Nishida, Toshisada

    2010-09-01

    In order to identify the causative agent of imported strongyloidiasis found in a Japanese mammalogist, who participated in a field survey in Tanzania, the hyper-variable region IV (HVR-IV) of 18S ribosomal DNA and partial mitochondrial cytochrome c-oxidase subunit 1 gene (cox1) were analyzed and compared with Strongyloides fuelleborni collected from apes and monkeys of Africa and Japan, and S. stercoralis from humans, apes and dogs. The HVR-IV and cox1 of the patient's worms were identical to or only slightly differed from those of worms parasitic in Tanzanian chimpanzees and yellow baboons, demonstrating that the patient acquired the infection during her field survey in Tanzania. Phylogenetic analysis with the maximum-likelihood method largely divided isolates of S. fuelleborni into three groups, which corresponded to geographical localities but not to host species. Meanwhile, isolates of S. stercoralis were grouped by the phylogenetic analysis into dog-parasitic and primate-parasitic clades, and not to geographical regions. It is surmised that subspeciation has occurred in S. fuelleborni during the dispersal of primates in Africa and Asia, while worldwide dispersal of S. stercoralis seems to have occurred more recently by migration and the activities of modern humans.

  9. Cloning, characterization, and sulfonamide and thiol inhibition studies of an α-carbonic anhydrase from Trypanosoma cruzi, the causative agent of Chagas disease.

    Science.gov (United States)

    Pan, Peiwen; Vermelho, Alane Beatriz; Capaci Rodrigues, Giseli; Scozzafava, Andrea; Tolvanen, Martti E E; Parkkila, Seppo; Capasso, Clemente; Supuran, Claudiu T

    2013-02-28

    An α-carbonic anhydrase (CA, EC 4.2.1.1) has been identified, cloned, and characterized from the unicellular protozoan Trypanosoma cruzi, the causative agent of Chagas disease. The enzyme (TcCA) has a very high catalytic activity for the CO2 hydration reaction, being similar kinetically to the human (h) isoform hCA II, although it is devoid of the His64 proton shuttle. A large number of aromatic/heterocyclic sulfonamides and some 5-mercapto-1,3,4-thiadiazoles were investigated as TcCA inhibitors. The aromatic sulfonamides were weak inhibitors (K(I) values of 192 nM to 84 μM), whereas some heterocyclic compounds inhibited the enzyme with K(I) values in the range 61.6-93.6 nM. The thiols were the most potent in vitro inhibitors (K(I) values of 21.1-79.0 nM), and some of them also inhibited the epimastigotes growth of two T. cruzi strains in vivo.

  10. Polymerase chain reaction detection of Leishmania DNA in skin biopsy samples in Sri Lanka where the causative agent of cutaneous leishmaniasis is Leishmania donovani.

    Science.gov (United States)

    Ranasinghe, Shalindra; Wickremasinghe, Renu; Hulangamuwa, Sanjeeva; Sirimanna, Ganga; Opathella, Nandimithra; Maingon, Rhaiza D C; Chandrasekharan, Vishvanath

    2015-12-01

    Leishmania donovani is the known causative agent of both cutaneous (CL) and visceral leishmaniasis in Sri Lanka. CL is considered to be under-reported partly due to relatively poor sensitivity and specificity of microscopic diagnosis. We compared robustness of three previously described polymerase chain reaction (PCR) based methods to detect Leishmania DNA in 38 punch biopsy samples from patients presented with suspected lesions in 2010. Both, Leishmania genus-specific JW11/JW12 KDNA and LITSR/L5.8S internal transcribed spacer (ITS)1 PCR assays detected 92% (35/38) of the samples whereas a KDNA assay specific forL. donovani (LdF/LdR) detected only 71% (27/38) of samples. All positive samples showed a L. donovani banding pattern upon HaeIII ITS1 PCR-restriction fragment length polymorphism analysis. PCR assay specificity was evaluated in samples containing Mycobacterium tuberculosis, Mycobacterium leprae, and human DNA, and there was no cross-amplification in JW11/JW12 and LITSR/L5.8S PCR assays. The LdF/LdR PCR assay did not amplify M. leprae or human DNA although 500 bp and 700 bp bands were observed in M. tuberculosis samples. In conclusion, it was successfully shown in this study that it is possible to diagnose Sri Lankan CL with high accuracy, to genus and species identification, using Leishmania DNA PCR assays.

  11. Inhibitors incorporating zinc-binding groups target the GlcNAc-PI de-N-acetylase in Trypanosoma brucei, the causative agent of African sleeping sickness.

    Science.gov (United States)

    Abdelwahab, Nuha Z; Crossman, Arthur T; Sullivan, Lauren; Ferguson, Michael A J; Urbaniak, Michael D

    2012-03-01

    Disruption of glycosylphosphatidylinositol biosynthesis is genetically and chemically validated as a drug target against the protozoan parasite Trypanosoma brucei, the causative agent of African sleeping sickness. The N-acetylglucosamine-phosphatidylinositol de-N-acetylase (deNAc) is a zinc metalloenzyme responsible for the second step of glycosylphosphatidylinositol biosynthesis. We recently reported the synthesis of eight deoxy-2-C-branched monosaccharides containing carboxylic acid, hydroxamic acid, or N-hydroxyurea substituents at the C2 position that may act as zinc-binding groups. Here, we describe the synthesis of a glucocyclitol-phospholipid incorporating a hydroxamic acid moiety and report the biochemical evaluation of the monosaccharides and the glucocyclitol-phospholipid as inhibitors of the trypanosome deNAc in the cell-free system and against recombinant enzyme. Monosaccharides with carboxylic acid or hydroxamic acid substituents were found to be the inhibitors of the trypanosome deNAc with IC(50) values 0.1-1.5mM and the glucocyclitol-phospholipid was found to be a dual inhibitor of the deNAc and the α1-4-mannose transferase with an apparent IC(50)= 19±0.5μm. © 2011 John Wiley & Sons A/S.

  12. Bioaccumulation of stentorin, the probable causative agent for discolored (“purple”) eggs and ovaries in blue catfish (Ictalurus furcatus) from Eufaula Lake, Oklahoma, USA

    Science.gov (United States)

    Gale, Robert W.; Papoulias, Diana M.; Schmitt, Christopher J.

    2015-01-01

    Observations of reddish to “purple” discolored eggs in the ovaries of adult female blue catfish (Ictalurus furcatus) from the northern arm of Eufaula Lake, a eutrophic multiuse impoundment in east-central Oklahoma, were first reported in 2006. Blue catfish eggs are normally cream to light yellow. Reports peaked in 2007–2008 and declined through 2009–2010; purple eggs have not been reported between 2010 and 2014. In the laboratory, all tissues and fluids of affected fish were strongly orange-red fluorescent under UV illumination, with the fluorescence most apparent in the lipid-rich ovaries and eggs. The causative agent was isolated chromatographically and confirmed by mass spectrometry as stentorin (1,3,4,6,8,10,11,13-octahydroxy-2,5-diisopropyl-phenanthro[1,10,9,8,o,p,q,r,a]perylene-7,14-dione), the fluorescent, lipophilic pigment associated with the photoreceptor protein of the ciliated protozoan Stentor coeruleus (Heterotrichea; Stentoridae). Larval medaka (Orizias latipes) readily consumed S. coeruleus in the laboratory and were observed to fluoresce in the same manner as the affected blue catfish. Potential deleterious effects of stentorin bioaccumulation remain to be determined, as do the geographic extent and the identities of other fluorescent compounds isolated from catfish eggs and ovaries.

  13. Testing of four Leishmania vaccine candidates in a mouse model of infection with Leishmania (Viannia) braziliensis, the main causative agent of cutaneous leishmaniasis in the New World.

    Science.gov (United States)

    Salay, G; Dorta, M L; Santos, N M; Mortara, R A; Brodskyn, C; Oliveira, C I; Barbiéri, C L; Rodrigues, M M

    2007-09-01

    We evaluated whether four recombinant antigens previously used for vaccination against experimental infection with Leishmania (Leishmania) major could also induce protective immunity against a challenge with Leishmania (Viannia) braziliensis, the species responsible for 90% of the 28,712 annual cases of cutaneous and mucocutaneous leishmaniasis recorded in Brazil during the year of 2004. Initially, we isolated the homolog genes encoding four L. (V.) braziliensis antigens: (i) homologue of receptor for activated C kinase, (ii) thiol-specific antioxidant, (iii) Leishmania elongation and initiation factor, and (iv) L. (L.) major stress-inducible protein 1. At the deduced amino acid level, all four open reading frames had a high degree of identity with the previously described genes of L. (L.) major being expressed on promastigotes and amastigotes of L. (V.) braziliensis. These genes were inserted into the vector pcDNA3 or expressed as bacterial recombinant proteins. After immunization with recombinant plasmids or proteins, BALB/c mice generated specific antibody or cell-mediated immune responses (gamma interferon production). After an intradermal challenge with L. (V.) braziliensis infective promastigotes, no significant reduction on the lesions was detected. We conclude that the protective immunity afforded by these four vaccine candidates against experimental cutaneous leishmaniasis caused by L. (L.) major could not be reproduced against a challenge with L. (V.) braziliensis. Although negative, we consider our results important since they suggest that studies aimed at the development of an effective vaccine against L. (V.) braziliensis, the main causative agent of cutaneous leishmaniasis in the New World, should be redirected toward distinct antigens or different vaccination strategies.

  14. Development and Evaluation of a Molecular Diagnostic Method for Rapid Detection of Histoplasma capsulatum var. farciminosum, the Causative Agent of Epizootic Lymphangitis, in Equine Clinical Samples.

    Science.gov (United States)

    Scantlebury, C E; Pinchbeck, G L; Loughnane, P; Aklilu, N; Ashine, T; Stringer, A P; Gordon, L; Marshall, M; Christley, R M; McCarthy, A J

    2016-12-01

    Histoplasma capsulatum var. farciminosum, the causative agent of epizootic lymphangitis (EZL), is endemic in parts of Africa. Diagnosis based on clinical signs and microscopy lacks specificity and is a barrier to further understanding this neglected disease. Here, a nested PCR method targeting the internal transcribed spacer (ITS) region of the rRNA operon was validated for application to equine clinical samples. Twenty-nine horses with signs of EZL from different climatic regions of Ethiopia were clinically examined. Blood samples and aspirates of pus from cutaneous nodules were taken, along with blood from a further 20 horses with no cutaneous EZL lesions. Among the 29 horses with suspected cases of EZL, H. capsulatum var. farciminosum was confirmed by extraction of DNA from pus and blood samples from 25 and 17 horses, respectively. Positive PCR results were also obtained with heat-inactivated pus (24 horses) and blood (23 horses) spotted onto Whatman FTA cards. Two positive results were obtained among blood samples from 20 horses that did not exhibit clinical signs of EZL. These are the first reports of the direct detection of H. capsulatum var. farciminosum in equine blood and at high frequency among horses exhibiting cutaneous lesions. The nested PCR outperformed conventional microscopic diagnosis, as characteristic yeast cells could be observed only in 14 pus samples. The presence of H. capsulatum var. farciminosum DNA was confirmed by sequencing the cloned PCR products, and while alignment of the ITS amplicons showed very little sequence variation, there was preliminary single nucleotide polymorphism-based evidence for the existence of two subgroups of H. capsulatum var. farciminosum This molecular diagnostic method now permits investigation of the epidemiology of EZL.

  15. Essential Oils of Myrtaceae Species Growing Wild in Tunisia: Chemical Variability and Antifungal Activity Against Biscogniauxia mediterranea, the Causative Agent of Charcoal Canker.

    Science.gov (United States)

    Yangui, Islem; Zouaoui Boutiti, Meriem; Boussaid, Mohamed; Messaoud, Chokri

    2017-07-01

    The chemical composition of five Eucalyptus species and five Myrtus communis L. populations was investigated using GC/MS and GC-FID. For Eucalyptus essential oils, 32 compounds, representing 88.56 - 96.83% of the total oil according to species, were identified. The main compounds were 1,8-cineole, α-pinene, p-cymene, γ-gurjunene, α-aromadendrene, and β-phellandrene. For Myrtle essential oils, 26 compounds, representing 93.13 - 98.91% of the total oil were identified. α-Pinene, 1,8-cineole, linalool, and myrtenyl acetate were found to be the major compounds. Principal component analysis (PCA) showed chemical differentiation between Eucalyptus species and between Myrtle populations. Biscogniauxia mediterranea, the causative agent of charcoal canker, was identified according to its morphological and molecular characteristics. Essential oils of the investigated Eucalyptus species and Myrtle populations were tested for their antifungal capacity against this fungus. The antifungal activity varied according to the essential oil composition. Biscogniauxia mediterranea exhibited powerful resistance to some essential oils including them of Eucalyptus lehmannii and Eucalyptus sideroxylon but it was very sensitive to Eucalyptus camaldulensis oil (IC50  = 3.83 mg/ml) and M. communis oil from Zaghouan (IC50  = 1 mg/ml). This sensitivity was found to be correlated to some essential oil compounds such as p-cymene, carvacrol, cuminaldehyde, and linalool. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  16. Testing of Four Leishmania Vaccine Candidates in a Mouse Model of Infection with Leishmania (Viannia) braziliensis, the Main Causative Agent of Cutaneous Leishmaniasis in the New World▿

    Science.gov (United States)

    Salay, G.; Dorta, M. L.; Santos, N. M.; Mortara, R. A.; Brodskyn, C.; Oliveira, C. I.; Barbiéri, C. L.; Rodrigues, M. M.

    2007-01-01

    We evaluated whether four recombinant antigens previously used for vaccination against experimental infection with Leishmania (Leishmania) major could also induce protective immunity against a challenge with Leishmania (Viannia) braziliensis, the species responsible for 90% of the 28,712 annual cases of cutaneous and mucocutaneous leishmaniasis recorded in Brazil during the year of 2004. Initially, we isolated the homolog genes encoding four L. (V.) braziliensis antigens: (i) homologue of receptor for activated C kinase, (ii) thiol-specific antioxidant, (iii) Leishmania elongation and initiation factor, and (iv) L. (L.) major stress-inducible protein 1. At the deduced amino acid level, all four open reading frames had a high degree of identity with the previously described genes of L. (L.) major being expressed on promastigotes and amastigotes of L. (V.) braziliensis. These genes were inserted into the vector pcDNA3 or expressed as bacterial recombinant proteins. After immunization with recombinant plasmids or proteins, BALB/c mice generated specific antibody or cell-mediated immune responses (gamma interferon production). After an intradermal challenge with L. (V.) braziliensis infective promastigotes, no significant reduction on the lesions was detected. We conclude that the protective immunity afforded by these four vaccine candidates against experimental cutaneous leishmaniasis caused by L. (L.) major could not be reproduced against a challenge with L. (V.) braziliensis. Although negative, we consider our results important since they suggest that studies aimed at the development of an effective vaccine against L. (V.) braziliensis, the main causative agent of cutaneous leishmaniasis in the New World, should be redirected toward distinct antigens or different vaccination strategies. PMID:17626159

  17. Potent Inhibition of Pseudogymnoascus destructans, the Causative Agent of White-Nose Syndrome in Bats, by Cold-Pressed, Terpeneless, Valencia Orange Oil.

    Directory of Open Access Journals (Sweden)

    Nicholas Boire

    Full Text Available The causative agent of White-nose Syndrome (WNS, Pseudogymnoascus destructans, has been shown to be fatal to several species of bats in North America. To date, no compounds or chemical control measures have been developed which eliminates the growth of the fungus in the environment or in affected animals. In the current study, we evaluated the activity of cold-pressed, terpeneless orange oil (CPT against multiple isolates of P. destructans in vitro. For all assays, a modified Kirby-Bauer disk diffusion assay was used. Standardized spore suspensions were prepared, adjusted to a specific optical density, and used to plate fungal lawns. Plates were incubated at either 15°C or 4°C for up to 6 months and checked at regular intervals for growth. Once controls had grown, zones of inhibition were measured (mm on test plates and compared to those obtained using current antifungal drugs. All P. destructans isolates were completely inhibited by 100% CPT (10 μL at 1 month of incubation regardless of temperature (4°C and 15°C. Complete inhibition persisted up to 6 months following a single exposure at this concentration. Of the standard antifungals, only amphotericin B demonstrated any activity, resulting in zone diameters ranging from 58 mm to 74 mm. CPT, at the highest concentration tested (100%, had no significant effect against a variety of other environmental organisms including various filamentous fungi, bacteria and aerobic actinomycetes. Given that CPT is relatively non-toxic, the possibility exists that the all-natural, mixture could be used as an environmental pre-treatment to eradicate P. destructans from bat habitats. Additional studies are needed to assess any undesirable effects of CPT on bat behavior and health and overall impacts on other members of the interconnected ecosystem(s.

  18. Study of the Prevalence of Causative Bacterial&Protozoal Agents of in Stool Samples of 470 Gastroenteritis Patients Referring to the Nikoopour Clinic in Yazd,Iran

    Directory of Open Access Journals (Sweden)

    MR Sharifi

    2004-04-01

    Full Text Available Interoduction: Gasteroenteritis is one of the problems worth consideration all over the world. It is one of the important causes of mortality, especially in children < 5 years of age, in developing countries including Iran. The aim of this descriptive study was to determine the demographic conditions influencing the presence of causative bacteria and protozoa, followed by antibiograms of isolated bacteria from stool samples of patients with gasteroenteritis referring to Nikoopour Clinic in the city of Yazd, Iran from 1998 – 2001. Materials and method: A total of 470 samples were microbiologically examined by direct method, culture and then antibiogramed. In order to isolate the possible bacteria, differential and selected media were used. Also, wet – mount technique was applied for detection of protozoa. Results: Results revealed that 272 samples (57.9% were infected by pathogenic bacteria or protozoa. 138 (50.8% pathogenic specimens were from male patients and the remaining 134(49.3% were from female patients. Isolated species were: Enteropathogenic E.coli 117(43%, Shigella 51(18.8%, Salmonella.interetidis 25(9.2%, C.jejuni 16(5.9%, Giardia lambdia 51(18.8% and Amoebae spp 12(4.4%. The most commonly detected shigella species was dysenteriae, (74.5% while boydii with 2% was the least common type observed in the specimens. Except shigella, all the other bacteria were more common in males than female, but insignificant statistically. In order to determine the sensitivity and/or resistance of pathogenic bacteria, antibiogram test was performed using selected antibiotic disks such as Ampicillin, Nalidixic Acid, Ciprofloxacin, Gentamycin and Sulfamethaxazole. Conclusion: Results revealed that some patients were probably infected by pathogenic factors other than bacteria or protozoa. Since all viruses and parasites are almost resistant to antibiotics and on the other hand, administration of antibiotics may lead to resistance of bacterial agents

  19. 260例浅部真菌病及致病菌种分析%Aanlysis on 260 cases of superficial mycosis and its causative agents

    Institute of Scientific and Technical Information of China (English)

    米拉; 帕丽达·阿布利孜; 刘旭; 董潇阳; 哈德丽亚; 周珊

    2011-01-01

    Objective To investigate the etiologic agents of superficial mycosis in Urmuqi and its distribution.Methods Direct microscopic check and fungi cultivation were performed on illness hairs, scales, nail debris of suspected superficial mycosis patients in the Department of Dermatology of the First Affiliated Hospital of Xinjiang Medical University during February 2004 to August 2010. For culture positive samples, bassed on the morphologic identification, the sequences of ITS region of ribosomal DNA (rDNA) were identified. The results were analysed by SPSS 17.0 statistical software. Results There were 260 cases showed positive results in both direct checking and cultivation. The positive rate of Tinea capitis culture was the highest (33. 1% ), followed by tinea corporis and cruris (28. 8% ), onychomycosis (21.5%) , and tinea manus and tinea pedis (16.5%). Strain identification revealed that Trichophyton (T.) rubrum was the most common agent in this study ( 28.5% ), followed by T. mentagrophytes ( 22.3% ), Microsporun ( M. ) canis ( 18.8% ) and T. tonsurans ( 10.0% ). M. canis was the most common causative agent of tinea capitis ( 16.2% ). Statistical analysis showed that in different genders and nations, tinea corporis and cruris, tinea manus and tinea pedis had statistical difference ( P < 0.05 ); those disease were all common for men, with the incidence in Han people higher than in Uyghur people. In different ages, tinea capitis, onychomycosis, tinea corporis and cruris, tinea manus and tinea pedis had statistical difference ( P < 0.05 ). Onychomycosis, tinea corporis and cruris, tinea manus and tinea pedis were common in middle-aged people, while tinea capitis was common in children. Conclusion T. rubrum is the main etiologic agent of superficial mycosis in Urmuqi. Tinea capitis is the moat important superficial mycosis for children in this area. M. canis is the most common causative agent of tinea capitis.%目的 了解新疆乌鲁木齐市

  20. Pyrazole derivatives as antitumor, anti-inflammatory and antibacterial agents.

    Science.gov (United States)

    Liu, Jia-Jia; Zhao, Meng-Yue; Zhang, Xin; Zhao, Xin; Zhu, Hai-Liang

    2013-11-01

    Within the past years, many researches on the synthesis, structure-activity relationships (SAR), antitumor, antiinflammatory and anti-bacterial activities of the pyrazole derivatives have been reported. Several pyrazole derivatives possess important pharmacological activities and they have been proved useful materials in drug research. Pyrazole derivatives play an important role in antitumor agents because of their good inhibitory activity against BRAF(V600E), EGFR, telomerase, ROS Receptor Tyrosine Kinase and Aurora-A kinase. In addition, pyrazole derivatives also show good antiinflammatory and anti-bacterial activities. In this review, the bioactivities of the pyrazole derivatives mentioned above will be summarized in detail. We sincerely hope that increasing knowledge of the SAR and cellular processes underlying the bioactivity of pyrazole derivatives will be beneficial to the rational design of new generation of small molecule drugs.

  1. Plant-Derived Agents for Counteracting Cisplatin-Induced Nephrotoxicity

    Science.gov (United States)

    Venkataraman, Balaji; Kurdi, Amani; Mahgoub, Eglal; Sadek, Bassem

    2016-01-01

    Cisplatin (CSP) is a chemotherapeutic agent commonly used to treat a variety of malignancies. The major setback with CSP treatment is that its clinical efficacy is compromised by its induction of organ toxicity, particular to the kidneys and ears. Despite the significant strides that have been made in understanding the mechanisms underlying CSP-induced renal toxicity, advances in developing renoprotective strategies are still lacking. In addition, the renoprotective approaches described in the literature reveal partial amelioration of CSP-induced renal toxicity, stressing the need to develop potent combinatorial/synergistic agents for the mitigation of renal toxicity. However, the ideal renoprotective adjuvant should not interfere with the anticancer efficacy of CSP. In this review, we have discussed the progress made in utilizing plant-derived agents (phytochemicals) to combat CSP-induced nephrotoxicity in preclinical studies. Furthermore, we have also presented strategies to utilize phytochemicals as prototypes for the development of novel renoprotective agents for counteracting chemotherapy-induced renal damage.

  2. Synthesis of substituted flavone derivatives as potent antimicrobial agents

    Directory of Open Access Journals (Sweden)

    T. Maruthavanan

    2011-12-01

    Full Text Available The biological activity of flavone has been enhanced by introducing heteroaryl moiety in C-2 position of chromone derivatives. Thus, 2-(1H-Indol-3-yl-4H-chromen-4-one derivatives (6a-e and 2-(2-chloroquinolin-3-yl-4H-chromen-4-one derivatives (7a-e were synthesized from corresponding chalcone. They were structurally confirmed by analytical and spectral data and evaluated for their antimicrobial activities. The results showed that this skeletal framework exhibited marked potency as antimicrobial agents.

  3. Benzothiazole Derivatives as Potential Anti-Infective Agents.

    Science.gov (United States)

    Sharma, Prabodh Chander; Bansal, Kushal Kumar; Deep, Aakash; Pathak, Meenakshi

    2017-01-01

    Severity of microbial infections and escalating resistance towards antibiotics has created a deep necessity for discovery of novel anti-infective agents. Heterocyclic chemistry of benzothiazole has become one of the most prolific areas in the field of drug discovery and development that has attracted great attention in recent time due to its increasing importance in the field of pharmaceuticals. The importance of benzothiazole and derivatives as potential antimicrobial agents has been well established and a large number of papers have been published in this regard. The present communication is an earnest attempt to review the chemistry, synthetic aspects including click chemistry and antimicrobial activities of benzothiazole derivatives reported in recent scientific literature. The scientific information of this manuscript may be worthwhile in encouraging the prospective researchers working on this heterocyclic scaffold.

  4. Mefloquine-oxazolidine derivatives: a new class of anticancer agents.

    Science.gov (United States)

    Rodrigues, Felipe A R; Bomfim, Igor da S; Cavalcanti, Bruno C; Pessoa, Claudia; Goncalves, Raoni S B; Wardell, James L; Wardell, Solange M S V; de Souza, Marcus V N

    2014-01-01

    A series of 23 racemic mefloquine-oxazolidine derivatives, 4-[3-(aryl)hexahydro[1,3]oxazolo[3,4-a]pyridin-1-yl]-2,8-bis(trifluoromethyl)quinolines, derived from (R*, S*)-(±)-mefloquine and arenealdehydes, have been evaluated for their activity against four cancer cell lines (HCT-8, OVCAR-8, HL-60, and SF-295). Good cytotoxicities have been determined with IC50 values ranging from 0.59 to 4.79 μg/mL. In general compounds with aryl groups having strong electron-releasing substituents, such as HO and MeO, or electron-rich heteroaryl groups, for example imidazol-2-y-l, are active. However, other factors such as steric effects may play a role. As both the active and non-active conformations of the mefloquine-oxazolidine derivatives are similar, it is concluded that molecular conformations do not play a significant role either. This study is the first to evaluate mefloquine derivatives as antitumor agents. The mefloquine-oxazolidine derivatives are considered to be useful leads for the rational design of new antitumor agents.

  5. Amphiphilic chitosan derivatives as carrier agents for rotenone

    Science.gov (United States)

    Kamari, Azlan; Aljafree, Nurul Farhana Ahmad

    2017-08-01

    In the present study, the feasibility of amphiphilic chitosan derivatives, namely oleoyl carboxymethyl chitosan (OCMCs), N,N-dimethylhexadecyl carboxymethyl chitosan (DCMCs) and deoxycholic acid carboxymethyl chitosan (DACMCs) as carrier agents for rotenone in water-insoluble pesticide formulations was investigated. Fourier Transform Infrared (FTIR) Spectrometer, CHN-O Elemental Analyser (CHN-O) and Transmission Electron Microscope (TEM) were used to characterise amphiphilic chitosan derivatives. The critical micelle concentration (CMC) of amphiphilic chitosan derivatives was determined using a Fluorescence Spectrometer. A High Performance Liquid Chromatography (HPLC) was used to determine the ability of OCMCs, DCMCs and DACMCs to load and release rotenone in an in vitro system. Based on TEM analysis, results have shown that amphiphilic chitosan derivatives formed self-assembly and exhibited spherical shape. The CMC values determined for OCMCs, DCMCs and DACMCs were 0.093, 0.098 and 0.468 mg/mL, respectively. The encapsulation efficiency (EE) values for the materials were more than 97.0%, meanwhile the loading capacity (LC) values were greater than 0.90%. OCMCs, DCMCs and DACMCs micelles exhibited an excellent ability to control the release of rotenone, of which 90.0% of rotenone was released within 40 to 52 h. In conclusion, OCMCs, DCMCs and DACMCs possess several key features to act as effective carrier agents for rotenone. Overall, amphiphilic chitosan derivatives produced in this study were successfully increased the solubility of rotenone by 49.0 times higher than free rotenone.

  6. Natural chromenes and chromene derivatives as potential anti-trypanosomal agents.

    Science.gov (United States)

    Batista, João Marcos; Lopes, Adriana Aparecida; Ambrósio, Daniela Luz; Regasini, Luis Octávio; Kato, Massuo Jorge; Bolzani, Vanderlan da Silva; Cicarelli, Regina Maria Barretto; Furlan, Maysa

    2008-03-01

    The aim of the study was to investigate the anti-trypanocidal activities of natural chromene and chromene derivatives. Five chromenes were isolated from Piper gaudichaudianum and P. aduncum, and a further seven derivatives were prepared using standard reduction, methylation and acetylation procedures. These compounds were assayed in vitro against epimastigote forms of Trypanosoma cruzi, the causative agent of Chagas disease. The results showed that the most of the compounds, especially those possessing electron-donating groups as substituents on the aromatic ring, showed potent trypanocidal activity. The most active compound, [(2S)-methyl-2-methyl-8-(3''-methylbut-2''-enyl)-2-(4'-methylpent-3'-enyl)-2H-chromene-6-carboxylate], was almost four times more potent than benznidazole (the positive control) and showed an IC50 of 2.82 microM. The results reveal that chromenes exhibit significant anti-trypanocidal activities and indicate that this class of natural product should be considered further in the development of new and more potent drugs for use in the treatment of Chagas disease.

  7. Plant-Derived Agents for Counteracting Cisplatin-Induced Nephrotoxicity

    Directory of Open Access Journals (Sweden)

    Shreesh Ojha

    2016-01-01

    Full Text Available Cisplatin (CSP is a chemotherapeutic agent commonly used to treat a variety of malignancies. The major setback with CSP treatment is that its clinical efficacy is compromised by its induction of organ toxicity, particular to the kidneys and ears. Despite the significant strides that have been made in understanding the mechanisms underlying CSP-induced renal toxicity, advances in developing renoprotective strategies are still lacking. In addition, the renoprotective approaches described in the literature reveal partial amelioration of CSP-induced renal toxicity, stressing the need to develop potent combinatorial/synergistic agents for the mitigation of renal toxicity. However, the ideal renoprotective adjuvant should not interfere with the anticancer efficacy of CSP. In this review, we have discussed the progress made in utilizing plant-derived agents (phytochemicals to combat CSP-induced nephrotoxicity in preclinical studies. Furthermore, we have also presented strategies to utilize phytochemicals as prototypes for the development of novel renoprotective agents for counteracting chemotherapy-induced renal damage.

  8. Thymol and eugenol derivatives as potential antileishmanial agents.

    Science.gov (United States)

    de Morais, Selene Maia; Vila-Nova, Nadja Soares; Bevilaqua, Claudia Maria Leal; Rondon, Fernanda Cristina; Lobo, Carlos Henrique; de Alencar Araripe Noronha Moura, Arlindo; Sales, Antônia Débora; Rodrigues, Ana Paula Ribeiro; de Figuereido, José Ricardo; Campello, Claudio Cabral; Wilson, Mary E; de Andrade, Heitor Franco

    2014-11-01

    In Northeastern Brazil visceral leishmaniasis is endemic with lethal cases among humans and dogs. Treatment is toxic and 5-10% of humans die despite treatment. The aim of this work was to survey natural active compounds to find new molecules with high activity and low toxicity against Leishmania infantum chagasi. The compounds thymol and eugenol were chosen to be starting compounds to synthesize acetyl and benzoyl derivatives and to test their antileishmanial activity in vitro and in vivo against L. i. chagasi. A screening assay using luciferase-expressing promastigotes was used to measure the growth inhibition of promastigotes, and an ELISA in situ was performed to evaluate the growth inhibition of amastigote. For the in vivo assay, thymol and eugenol derivatives were given IP to BALB/c mice at 100mg/kg/day for 30 days. The thymol derivatives demonstrated the greater activity than the eugenol derivatives, and benzoyl-thymol was the best inhibitor (8.67 ± 0.28 μg/mL). All compounds demonstrated similar activity against amastigotes, and acetyl-thymol was more active than thymol and the positive control drug amphotericin B. Immunohistochemistry demonstrated the presence of Leishmania amastigote only in the spleen but not the liver of mice treated with acetyl-thymol. Thus, these synthesized derivatives demonstrated anti-leishmanial activity both in vitro and in vivo. These may constitute useful compounds to generate new agents for treatment of leishmaniasis.

  9. Evaluation of labdane derivatives as potential anti-inflammatory agents.

    Science.gov (United States)

    Girón, Natalia; Pérez-Sacau, Elisa; López-Fontal, Raquel; Amaro-Luis, Juan M; Hortelano, Sonsoles; Estevez-Braun, Ana; de Las Heras, Beatriz

    2010-07-01

    In the present study, a series of labdane derivatives (2-9) were prepared from labdanediol (1) and their potential as anti-inflammatory agents were evaluated on lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. All compounds were able to inhibit LPS-induced nitric oxide (NO), although compounds 1, 2, 5, 8 and 9 exhibited the most potent effects with a range of IC(50) values of 5-15 microM. Similarly to the inhibitory effects on NO release, these labdane derivatives also inhibited prostaglandin E(2) (PGE(2)) production. However, analysis of cell viability demonstrated that effects on NO release and (PGE(2)) production of compounds 1, 8 and 9 were due to citotoxicity, whereas compound 2 and 5 did not show any effect in the survival of RAW 264.7 macrophages. In addition to these in vitro data, compound 5 also showed anti-inflammatory activity in vivo, when tested in mice. They prevented the extent of swelling in the TPA-induced ear edema model and inhibited MPO activity, showing similar potency to that of the widely used anti-inflammatory drug indomethacin. These results indicate that compound 2 and in particular compound 5 might be used for the design of new anti-inflammatory agents. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

  10. Chemokine-Derived Peptides: Novel Antimicrobial and Antineoplasic Agents

    Science.gov (United States)

    Valdivia-Silva, Julio; Medina-Tamayo, Jaciel; Garcia-Zepeda, Eduardo A.

    2015-01-01

    Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP) with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer. PMID:26062132

  11. Chemokine-Derived Peptides: Novel Antimicrobial and Antineoplasic Agents

    Directory of Open Access Journals (Sweden)

    Julio Valdivia-Silva

    2015-06-01

    Full Text Available Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/ chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer.

  12. Evaluation of natural anthracene-derived compounds as antimitotic agents.

    Science.gov (United States)

    Badria, Farid A; Ibrahim, Ahmed S

    2013-04-01

    Plants that contain anthracene-derived compounds such as anthraquinones have been reported to act as anticancer besides their use for millennia to treat constipation, but the mechanism of action is still unfolding. Therefore we pursue this study to explore a new horizon in the anticancer property of these agents with relevance to mitotic arrest. To achieve this goal, the antimitotic activity of a series of naturally occurring anthracene-derived anthraquinones including anthrone, alizarin (1,2-dihydroxyanthraquinone), quinizarin (1,4-dihydroxyanthraquinone), rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid), emodin (1,6,8-trihydroxy-3-methylanthraquinone), and aloe emodin (1,8-dihydroxy-3-hydroxymethylanthraquinone) were evaluated using Allium cepa root tips. Initial results revealed that the mitosis was inhibited after 3, 6, and 24 h, respectively, of incubation with 500, 250, and 125 ppm of each compound in a dose-dependent manner. Furthermore, alizarin at 500 ppm was proved to be the most active compound to arrest the mitosis after 24 h followed by emodin, aloe emodin, rhein, and finally quinizarin. Interestingly, this inhibition of mitosis was irreversible in root tips incubated with each compound at concentration of 500 ppm but not with 250 ppm or 125 ppm, where the roots regained their normal mitotic activity after 96 h post-incubation in water. This re-evaluation of an old remedy suggests that several bioactive anthraquinones possess promising anti-mitotic activity that may have the potential to be lead compounds for the development of a new class of multifaceted natural anticancer/antimitotic agents.

  13. Pyridine-grafted chitosan derivative as an antifungal agent.

    Science.gov (United States)

    Jia, Ruixiu; Duan, Yunfei; Fang, Qiang; Wang, Xiangyang; Huang, Jianying

    2016-04-01

    Pyridine moieties were introduced into chitosan by nucleophilic substitution to afford N-(1-carboxybutyl-4-pyridinium) chitosan chloride (pyridine chitosan). The resulting chitosan derivative was well characterized, and its antifungal activity was examined, based on the inhibition of mycelial growth and spore germination. The results indicated that pyridine chitosan exhibited enhanced antifungal activity by comparison with pristine chitosan. The values of the minimum inhibitory concentration and the minimal fungicidal concentration of pyridine chitosan against Fulvia fulva were 0.13 mg/ml and 1 mg/ml, respectively, while the corresponding values against Botrytis cinerea were 0.13 mg/ml and 4 mg/ml, respectively. Severe morphological changes of pyridine chitosan-treated B. cinerea were observed, indicative that pyridine chitosan could damage and deform the structure of fungal hyphae and subsequently inhibit strain growth. Non-toxicity of pyridine chitosan was demonstrated by an acute toxicity study. These results are beneficial for assessing the potential utilization of this chitosan derivative and for exploring new functional antifungal agents with chitosan in the food industry.

  14. Fixed drug eruption induced by an iodinated non-ionic X-ray contrast medium: a practical approach to identify the causative agent and to prevent its recurrence

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Ingrid; Block, Wolfgang; Schild, Hans H. [University of Bonn, Department of Radiology, Bonn (Germany); Medina, Jesus; Prieto, Pilar [JUSTESA IMAGEN SA, Biological R and D Department, Madrid (Spain)

    2007-02-15

    We describe the case of a 61-year-old physician who developed a fixed drug eruption (FDE) after i.v. administration of a non-ionic monomeric iodinated X-ray contrast medium (CM) (iopromide). During CM injection, a sensation of heat occurred, which was most intense in the right inguinal region. Four hours later, the FDE arose with a red macule of approximately 2 cm in diameter covering a dermal infiltration in the right inguinal region, and enlarged up to a final size of 15 x 8 cm, accompanied by a burning sensation. The patient's history revealed a similar reaction in the same localization and of the same clinical appearance after CM injection 1 year before. Patch testing 4 months later revealed positive reactions to iomeprol and iohexol. Iopamidol injection for another CT examination 23 months later was well tolerated. Based on these results, we suggest patch testing after CM-induced FDE, which could help to select a CM for future CT examinations. Late onset of adverse CM reactions may manifest as FDE. Patch testing within the previous skin reaction area is the diagnostic tool that should be used to confirm the suspected agent, possible cross-reacting agents and well-tolerated agents. (orig.)

  15. Polycyclic propargylamine and acetylene derivatives as multifunctional neuroprotective agents.

    Science.gov (United States)

    Zindo, Frank T; Barber, Quinton R; Joubert, Jacques; Bergh, Jacobus J; Petzer, Jacobus P; Malan, Sarel F

    2014-06-10

    The aim of this study was to design drug-like molecules with multiple neuroprotective mechanisms which would ultimately inhibit N-methyl-D-aspartate (NMDA) receptors, block L-type voltage gated calcium channels (VGCC) and inhibit apoptotic processes as well as the monoamine oxidase-B (MAO-B) enzyme in the central nervous system. These types of compounds may act as neuroprotective and symptomatic drugs for disorders such as Alzheimer's and Parkinson's disease. In designing the compounds we focused on the structures of rasagiline and selegiline, two well known MAO-B inhibitors and proposed neuroprotective agents. Based on this consideration, the compounds synthesised all contain the propargylamine functional group of rasagiline and selegiline or a derivative thereof, conjugated to various polycyclic cage moieties. Being non-polar, these polycyclic moieties have been shown to aid in the transport of conjugated compounds across the blood-brain barrier, as well as cell membranes and have secondary positive neuroprotective effects. All novel synthesised polycyclic derivatives proved to have significant anti-apoptotic activity (p < 0.05) which was comparable to the positive control, selegiline. Four compounds (12, 15 and 16) showed promising VGCC and NMDA receptor channel inhibitory activity ranging from 18% to 59% in micromolar concentrations and compared favourably to the reference compounds. In the MAO-B assay, 8-phenyl-ethynyl-8-hydroxypentacycloundecane (10), exhibited MAO-B inhibition of 73.32% at 300 μM. This compound also reduced the percentage of apoptotic cells by as much as 40% when compared to the control experiments.

  16. Probabilistic Causation without Probability.

    Science.gov (United States)

    Holland, Paul W.

    The failure of Hume's "constant conjunction" to describe apparently causal relations in science and everyday life has led to various "probabilistic" theories of causation of which the study by P. C. Suppes (1970) is an important example. A formal model that was developed for the analysis of comparative agricultural experiments…

  17. The filamentous phage XacF1 causes loss of virulence in Xanthomonas axonopodis pv. citri, the causative agent of citrus canker disease

    Directory of Open Access Journals (Sweden)

    Abdelmonim Ali Ahmad

    2014-07-01

    Full Text Available In this study, filamentous phage XacF1, which can infect Xanthomonas axonopodis pv. citri (Xac strains, was isolated and characterized. Electron microscopy showed that XacF1 is a member of the family Inoviridae and is about 1000 nm long and 16 nm in width. The genome of XacF1 is 7325 nucleotides in size, containing 13 predicted open reading frames (ORFs, some of which showed significant homology to Ff-like phage proteins such as ORF1 (pII, ORF2 (pV, ORF6 (pIII, and ORF8 (pVI. XacF1 showed a relatively wide host range, infecting seven out of 11 strains tested in this study. Frequently, XacF1 was found to be integrated into the genome of Xac strains. This integration occurred at the host dif site (attB and was mediated by the host XerC/D recombination system. The attP sequence was identical to that of Xanthomonas phage Cf1c. Interestingly, infection by XacF1 phage caused several physiological changes to the bacterial host cells, including lower levels of extracellular polysaccharide production, reduced motility, slower growth rate, and a dramatic reduction in virulence. In particular, the reduction in virulence suggested possible utilization of XacF1 as a biological control agent against citrus canker disease.

  18. Three Leishmania/L. species--L. infantum, L. major, L. tropica--as causative agents of mucosal leishmaniasis in Iran.

    Science.gov (United States)

    Shirian, Sadegh; Oryan, Ahmad; Hatam, Gholam Reza; Daneshbod, Yahya

    2013-07-01

    Cases of human oro-mucosal leishmaniasis are mainly reported in areas where Leishmania (Viannia) braziliensis perpetuates and the damages are mainly located at the cartilaginous nasal septum and frontal portions of the nasal fossa. In Iran, an area free of any L.(V) braziliensis, three Leishmania species are known to perpetuate through distinct (i) blood-feeding sand flies and (ii) rodents or (iii) canidae. Thus while establishing the diagnosis of any human oro-mucosal lesions, three Leishmania species - L. infantum, L. major, and L. tropica - must be considered as potential etiological agents of these damages. With these objectives in mind, features such as localization, extent, severity of oro-mucosal lesions, and duration of symptoms at the time of diagnosis were recorded from 11 patients with respect to the presence or absence of cutaneous lesions in other body parts. The biopsy samples were collected from the oro-mucosal and cutaneous lesions and were processed for further identification of the Leishmania species. The lesions ranged from mucosal nodules without ulceration, nodules with erosion, and shallow to deep ulcerations. Leishmania major was isolated from six (55%) cases showing lesions or scars. The scars were restricted to upper and lower extremities. For the other five patients who did not display any signs of former or active cutaneous leishmaniasis, L. major, L. tropica, and L. infantum were isolated from their lesions. In conclusion L. major, L. infantum, and L. tropica, regardless of common tropism, can be seen in mucosal tissues. However, L. major was the predominant species detected from the lesions in the nasal, gingival, and hard and soft palates, and L. tropica was isolated from the gingival and lower lip lesions. Leishmania infantum was isolated from two severe cases of deep mucosal damage displayed by the epiglottis, cricoarytenoid muscle, and laryngeal mucosa. One important finding was the association of L. major with active or scarred

  19. Identification and functional analysis of the S-layer protein SplA of Paenibacillus larvae, the causative agent of American Foulbrood of honey bees.

    Science.gov (United States)

    Poppinga, Lena; Janesch, Bettina; Fünfhaus, Anne; Sekot, Gerhard; Garcia-Gonzalez, Eva; Hertlein, Gillian; Hedtke, Kati; Schäffer, Christina; Genersch, Elke

    2012-01-01

    The gram-positive, spore-forming bacterium Paenibacillus larvae is the etiological agent of American Foulbrood (AFB), a globally occurring, deathly epizootic of honey bee brood. AFB outbreaks are predominantly caused by two genotypes of P. larvae, ERIC I and ERIC II, with P. larvae ERIC II being the more virulent genotype on larval level. Recently, comparative proteome analyses have revealed that P. larvae ERIC II but not ERIC I might harbour a functional S-layer protein, named SplA. We here determine the genomic sequence of splA in both genotypes and demonstrate by in vitro self-assembly studies of recombinant and purified SplA protein in combination with electron-microscopy that SplA is a true S-layer protein self-assembling into a square 2D lattice. The existence of a functional S-layer protein is novel for this bacterial species. For elucidating the biological function of P. larvae SplA, a genetic system for disruption of gene expression in this important honey bee pathogen was developed. Subsequent analyses of in vivo biological functions of SplA were based on comparing a wild-type strain of P. larvae ERIC II with the newly constructed splA-knockout mutant of this strain. Differences in cell and colony morphology suggest that SplA is a shape-determining factor. Marked differences between P. larvae ERIC II wild-type and mutant cells with regard to (i) adhesion to primary pupal midgut cells and (ii) larval mortality as measured in exposure bioassays corroborate the assumption that the S-layer of P. larvae ERIC II is an important virulence factor. Since SplA is the first functionally proven virulence factor for this species, our data extend the knowledge of the molecular differences between these two genotypes of P. larvae and contribute to explaining the observed differences in virulence. These results present an immense advancement in our understanding of P. larvae pathogenesis.

  20. Fusarium keratitis in South India: causative agents, their antifungal susceptibilities and a rapid identification method for the Fusarium solani species complex.

    Science.gov (United States)

    Homa, Mónika; Shobana, Coimbatore S; Singh, Yendrembam R B; Manikandan, Palanisamy; Selvam, Kanesan P; Kredics, László; Narendran, Venkatapathy; Vágvölgyi, Csaba; Galgóczy, László

    2013-09-01

    Seventy Fusarium isolates derived from human keratomycosis were identified based on partial sequences of the β-tubulin (β-TUB) and translation elongation factor 1α (EF-1α) genes. Most of the isolates were confirmed as members of the F. solani species complex (75.71%), followed by the F. dimerum species complex (8.57%), the F. fujikuroi species complex (8.57%), the F. oxysporum species complex (4.29%) and the F. incarnatum-equiseti species complex (2.86%). A combined phylogenetic tree was estimated including all the 70 isolates. Isolates belonging to different species complexes formed separate clades. In this study, we also report the first isolation of F. napiforme from human keratomycosis. A new method based on a specific EcoRI restriction site in the EF-1α gene was developed for the rapid identification of F. solani. In vitro antifungal susceptibilities of the isolates to seven antifungals were determined by broth microdilution method. Terbinafine, natamycin and amphotericin B proved to be the most effective drugs, followed by voriconazole. The minimal inhibitory concentrations of clotrimazole, econazole and itraconazole were generally high (≥64 μg ml(-1) ). The interactions between the two most effective antifungals (natamycin and terbinafine) were determined by checkerboard microdilution method. Synergism (71.8%) or no interaction (28.2%) was revealed between the two compounds. © 2013 Blackwell Verlag GmbH.

  1. Causation and International State Responsibility

    NARCIS (Netherlands)

    Castellanos-Jankiewicz, L.

    2012-01-01

    This work studies causation in the law of international State responsibility. It is submitted that the absence of causation as an element of the internationally wrongful act owes more to the structure of international law, than to the inadequateness of causation as a conceptual and legal construct t

  2. Comparison of the susceptibility of brown trout (Salmo trutta) and four rainbow trout (Oncorhynchus mykiss) strains to the myxozoan Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease (PKD).

    Science.gov (United States)

    Grabner, Daniel S; El-Matbouli, Mansour

    2009-11-12

    Differences in susceptibility to the myxozoan parasite Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease (PKD), between four strains of rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta) were evaluated. Fish were exposed to water enzootic for the parasite in the field for 5 days and were subsequently transferred to the laboratory. Relative parasite load was determined after 2, 3 and 4 weeks post-exposure (wpe) by quantitative real-time PCR (qPCR) of kidney samples and number of parasite stages was determined in immunohistochemical stained sections of kidney, liver and spleen tissues. According to qPCR results, the highest amount of parasite DNA per equal amount of host tissue at all time points was measured in brown trout. Two of the rainbow trout strains showed lower relative parasite load than all other groups at the beginning of the experiment, but the parasite multiplied faster in these strains resulting in an equal level of relative parasite load for all rainbow trout strains at 4 wpe. A weak negative correlation of fish size and parasite load was detected. Only in samples of a few fish, single stages of T. bryosalmonae were found in sections stained by immunohistochemistry impeding quantitative evaluation of parasite numbers by this method. The results indicate a differential resistance to T. bryosalmonae between the rainbow trout strains investigated and between rainbow trout and brown trout.

  3. CAUSATIVE AGENTS OF KERATOMYCOSIS IN IBADAN: REVIEW ...

    African Journals Online (AJOL)

    boaz

    The media with no obvious growth after 3-4 weeks of incubation were regarded as negative. Results: A total of 48 ... corneal ulceration result in 1.5 to 2 million new cases of corneal ... fungal pathogens in South India is significantly greater than ...

  4. HELICOBACTER PYLORI: THE CAUSATIVE AGENT OF PEPTIC ...

    African Journals Online (AJOL)

    DR. AMINU

    some of the virulence factors possessed by the organism, its metabolism and growth .... lymphoma and some types of gastric adenocarcinoma .... carbon to the lungs, where the patient exhales it. .... pylori as a risk factor for cancer, Bailliere's.

  5. Synthesis of Polyfunctionally Substituted Fused Pyrimidine Derivatives as Antimicrobial Agents

    Institute of Scientific and Technical Information of China (English)

    EISSA, Abd EI-Monem Mohamed Farag

    2008-01-01

    A variety of pyrimidine derivatives 2--4 and annulated pyrimidine derivatives 5-17 have been synthesized via a sequence of heterocyclization reaction of readily available 6-naphthyl-4-oxo-2-thioxo-1,2,3,4-tetrahydroprimi-dine-5-carbonitrile (1) with different acidic and basic reagents. The new compounds were synthesized with the aim of study of their antimicrobial activity. The structures of all synthesized compounds were elucidated by elemental analysis and spectroscopic studies.

  6. Dihydroethanoanthracene Derivatives as In Vitro Malarial Chloroquine Resistance Reversal Agents

    Science.gov (United States)

    Millet, Julie; Torrentino-Madamet, Marylin; Alibert, Sandrine; Rogier, Christophe; Santelli-Rouvier, Christiane; Mosnier, Joel; Baret, Eric; Barbe, Jacques; Parzy, Daniel; Pradines, Bruno

    2004-01-01

    The ability of four 9,10-dihydroethanoanthracene derivatives (BG920, BG932, BG958, and BG996), as well as verapamil and promethazine, to reverse chloroquine resistance was assessed against 24 chloroquine-resistant and 10 chloroquine-susceptible strains of Plasmodium falciparum from different countries. The 9,10-dihydroethanoanthracene derivatives clearly increase chloroquine susceptibility only in chloroquine-resistant isolates. PMID:15215144

  7. Identification of novel and improved antimitotic agents derived from noscapine.

    Science.gov (United States)

    Anderson, James T; Ting, Anthony E; Boozer, Sherry; Brunden, Kurt R; Crumrine, Chris; Danzig, Joel; Dent, Tom; Faga, Laurel; Harrington, John J; Hodnick, William F; Murphy, Steven M; Pawlowski, Gary; Perry, Robert; Raber, Amy; Rundlett, Stephen E; Stricker-Krongrad, Alain; Wang, Jianmin; Bennani, Youssef L

    2005-11-17

    Analogues of the natural product noscapine were synthesized and their potential as antitumor agents evaluated. The discovery of a novel regioselective O-demethylation facilitated the synthesis of the potent aniline 6, which arrests mammalian cells in the G2/M phase of the cell cycle at 0.1 microM and also affects tubulin polymerization. Aniline 6 is orally bioavailable and is 250-fold more potent than noscapine in reducing cell proliferation in rapidly dividing cells.

  8. Synthesis and Biological Evaluation of Hydrazone Derivatives as Antifungal Agents

    Directory of Open Access Journals (Sweden)

    Bruna B. Casanova

    2015-05-01

    Full Text Available Emerging yeasts are among the most prevalent causes of systemic infections with high mortality rates and there is an urgent need to develop specific, effective and non-toxic antifungal agents to respond to this issue. In this study 35 aldehydes, hydrazones and hydrazines were obtained and their antifungal activity was evaluated against Candida species (C. parapsilosis, C. tropicalis, C. krusei, C. albicans, C. glabrata and C. lusitaneae and Trichosporon asahii, in an in vitro screening. The minimum inhibitory concentrations (MICs of the active compounds in the screening was determined against 10 clinical isolates of C. parapsilosis and 10 of T. asahii. The compounds 4-pyridin-2-ylbenzaldehyde] (13a and tert-butyl-(2Z-2-(3,4,5-trihydroxybenzylidinehydrazine carboxylate (7b showed the most promising MIC values in the range of 16–32 μg/mL and 8–16 μg/mL, respectively. The compounds’ action on the stability of the cell membrane and cell wall was evaluated, which suggested the action of the compounds on the fungal cell membrane. Cell viability of leukocytes and an alkaline comet assay were performed to evaluate the cytotoxicity. Compound 13a was not cytotoxic at the active concentrations. These results support the discovery of promising candidates for the development of new antifungal agents.

  9. New 1-Aryl-3-Substituted Propanol Derivatives as Antimalarial Agents

    Directory of Open Access Journals (Sweden)

    Antonio Monge

    2009-10-01

    Full Text Available This paper describes the synthesis and in vitro antimalarial activity against a P. falciparum 3D7 strain of some new 1-aryl-3-substituted propanol derivatives. Twelve of the tested compounds showed an IC50 lower than 1 μM. These compounds were also tested for cytotoxicity in murine J774 macrophages. The most active compounds were evaluated for in vivo activity against P. berghei in a 4-day suppressive test. Compound 12 inhibited more than 50% of parasite growth at a dose of 50 mg/kg/day. In addition, an FBIT test was performed to measure the ability to inhibit ferriprotoporphyrin biocrystallization. This data indicates that 1-aryl-3-substituted propanol derivatives hold promise as a new therapeutic option for the treatment of malaria.

  10. Novel aryl carbamate derivatives of metronidazole as potential antiamoebic agents.

    Science.gov (United States)

    Hayat, Faisal; Wahedi, Hussain Mustatab; Park, Seonghyeok; Tariq, Saba; Azam, Amir; Shin, Dongyun

    2016-01-01

    A series of novel aryl carbamate derivatives of metronidazole (MNZ) were designed, synthesized, and screened for antiamoebic activity. As compared to MNZ, most of the derivatives exhibited moderate to excellent activity against the HM1:IMSS strain of Entamoeba histolytica. Compounds 7, 14, 16, 19, and 21 exhibited the most promising antiamoebic activity with IC50 values of 0.24, 0.08, 0.26, 0.26, and 0.15 μM, respectively, compared to that of MNZ (1.78 μM). Moreover, from the toxicological studies of these compounds on human melanocytes, the melan-a cell line revealed that the potent compounds are nontoxic at concentrations ranging from 2.5 to 50 μM.

  11. Synthesis of Some Oxadiazole Derivatives as New Anticandidal Agents

    Directory of Open Access Journals (Sweden)

    Zafer Asim Kaplancikli

    2011-09-01

    Full Text Available In this study, 5-[(pyrimidin-2-ylthiomethyl]-1,3,4-oxadiazole-2(3H-thione (3 was synthesized via the ring closure reaction of 2-(pyrimidin-2-ylthioacetohydrazide (2 with carbon disulphide. New oxadiazole derivatives 4a-f were obtained by the nucleophilic substitution reaction of compound 3 with various phenacyl bromides. The chemical structures of the compounds were elucidated by IR, 1H-NMR, 13C-NMR and FAB+-MS spectral data and elemental analyses. The newly synthesized derivatives 4a-f were tested in vitro by using a microbroth dilution method against C. albicans (clinical isolate, Osmangazi University, Faculty of Medicine, Eskişehir, Turkey, C. albicans (ATCC 90028, C. glabrata (clinical isolate, Osmangazi University, Faculty of Medicine, Eskişehir, Turkey, C. tropicalis (NRRL Y-12968, C. krusei (NRRL Y-7179, C. parapsilosis (NRRL Y- 12696, C. albicans (NRRL Y-12983, C. glabrata (clinical isolate, Anadolu University, Faculty of Science, Department of Biology, Eskişehir, Turkey. Among these compounds, compound 4a was found to be the most potent derivative (MIC = 0.007–0.06 versus ketoconazole: 0.001–0.007 mg/mL against Candida species, except C. tropicalis and C. krusei when compared with the standard antifungal ketoconazole.

  12. High-throughput Identification of Phage-derived Imaging Agents

    Directory of Open Access Journals (Sweden)

    Kimberly A. Kelly

    2006-01-01

    Full Text Available The use of phage-displayed peptide libraries is a powerful method for selecting peptides with desired binding properties. However, the validation and prioritization of “hits” obtained from this screening approach remains challenging. Here, we describe the development and testing of a new analysis method to identify and display hits from phage-display experiments and high-throughput enzyme-linked immunosorbent assay screens. We test the method using a phage screen against activated macrophages to develop imaging agents with higher specificity for active disease processes. The new methodology should be useful in identifying phage hits and is extendable to other library screening methods such as small-molecule and nanoparticle libraries.

  13. Synthesis of Novel Quinazoline Derivatives as Antimicrobial Agents

    Institute of Scientific and Technical Information of China (English)

    ALY,A.A

    2003-01-01

    Quinazoline isothiocyanate 1 reacts with various nucleophiles(nitrogen nucleophiles,oxygen nucleophiles and sulphur nucleophiles)to afford heterocyclic systemes 2-13,Also,the [4+2] cycloaddition reaction of 1 with phenyl isocyanate,benzylidene aryl amine and cinnamic acid derivatives gave novel heterocyclic compounds 14-16,Moreover,the reaction of 1 with active methylene compounds under Michael reaction conditions also was investigated to yield 17 and 18 and it was found that all these reactions proceede via isothiocyanate heterocyclization to furnish non-condensed heterocyclic compoundes,Some of the newly synthesized compounds were tested for their antimicrobial activities.

  14. Erythrocyte-derived optical nano-vesicles as theranostic agents

    Science.gov (United States)

    Mac, Jenny T.; Nunez, Vicente; Bahmani, Baharak; Guerrero, Yadir; Tang, Jack; Vullev, Valentine I.; Anvari, Bahman

    2015-07-01

    We have engineered nano-vesicles, derived from erythrocytes, which can be doped with various near infrared (NIR) organic chromophores, including the FDA-approved indocyanine green (ICG). We refer to these vesicles as NIR erythrocyte-mimicking transducers (NETS) since in response to NIR photo-excitation they can generate heat or emit fluorescent light. Using biochemical methods based on reduction amination, we have functionalized the surface of NET with antibodies to target specific biomolecules. We present results that demonstrate the effectiveness of NETs in targeted imaging of cancer cells that over-express the human epidermal growth factor receptor-2 (HER2).

  15. Onicomicosis: epidemiología, agentes causales y evaluación de los métodos diagnósticos de laboratorio Onychomycoses: epidemiology, causative agents and assessment of diagnostic laboratory methods

    Directory of Open Access Journals (Sweden)

    Javier R Nazar

    2012-03-01

    Full Text Available Desde marzo de 2007 hasta marzo de 2011 se estudiaron prospectivamente 414 pacientes con onicodistrofias en un laboratorio privado de Esquel. La prevalencia de onicomicosis de pie fue del 78 %; la de mano, del 58 %. Los principales agentes etiológicos fueron Trichophyton rubrum, Candida spp. y Trichophyton mentagrophytes. El desarrollo de dermatofitos prevaleció en las onicopatías de pie y el de Candida spp. en las de uñas de mano (ambos, p Since March 2007 to March 2011, 414 patients with onychopathies were prospectively analyzed. Prevalence of the toenail and fingernail mycoses was 78 % and 58 %, respectively. The major etiological agents were Trichophyton rubrum, Candida spp. and Trichophyton mentagrophytes. Dermatophytes were more frequently cultured from toenails, whereas Candida spp. from fingernails (both, p < 0.05. In candidal onychomycosis, species different from C. albicans were prevalent. A higher prevalence of toenail and fingernail mycoses, a predominance of T. rubrum in toenails (p < 0.05, and greater positivity in the direct examination (DE and in culture (both, p < 0.05 were more frequently observed in men than in women. The correlation between DE and culture was 68 %. DE and culture yields were associated with a greater size lesion. DE was more effective in onycodystrophies with duration of more than 5 years. Culture positivity was independent of nail affection chronicity.

  16. Small Peptides Derived from Penetratin as Antibacterial Agents.

    Science.gov (United States)

    Parravicini, Oscar; Somlai, Csaba; Andujar, Sebastián A; Garro, Adriana D; Lima, Beatriz; Tapia, Alejandro; Feresin, Gabriela; Perczel, Andras; Tóth, Gabor; Cascales, Javier López; Rodríguez, Ana M; Enriz, Ricardo D

    2016-04-01

    The synthesis, in vitro evaluation and conformational study of several small-size peptides acting as antibacterial agents are reported. Among the compounds evaluated, the peptides Arg-Gln-Ile-Lys-Ile-Trp-Arg-Arg-Met-Lys-Trp-Lys-Lys-NH2 , Arg-Gln-Ile-Lys-Ile-Arg-Arg-Met-Lys-Trp-Arg-NH2 , and Arg-Gln-Ile-Trp-Trp-Trp-Trp-Gln-Arg-NH2 exhibited significant antibacterial activity. These were found to be very active antibacterial compounds, considering their small molecular size. In order to better understand the antibacterial activity obtained for these peptides, an exhaustive conformational analysis was performed, using both theoretical calculations and experimental measurements. Molecular dynamics simulations using two different media (water and trifluoroethanol/water) were employed. The results of these theoretical calculations were corroborated by experimental circular dichroism measurements. A brief discussion on the possible mechanism of action of these peptides at molecular level is also presented. Some of the peptides reported here constitute very interesting structures to be used as starting compounds for the design of new small-size peptides possessing antibacterial activity.

  17. Thalidomide-derived immunomodulatory drugs as therapeutic agents.

    Science.gov (United States)

    Galustian, Christine; Labarthe, Marie-Christine; Bartlett, J Blake; Dalgleish, Angus G

    2004-12-01

    Thalidomide, a drug originally used to treat morning sickness, was removed from the market place in the early 1960s after it was found to cause serious congenital birth defects. However, thalidomide has recently been investigated in a new light following its activity in a number of chronic diseases. Moreover, like thalidomide itself, its second-generation immunomodulatory drug (IMiD) analogues have been shown to act as powerful anticancer agents and are clearly active in the treatment of patients with relapsed multiple myeloma. These new drugs, in particular the second-generation IMiDs, lenalidomide (CC-5013, REVLIMID; Celgene Corp., NJ, USA) and CC-4047 (ACTIMID; Celgene Corp.), offer improvements over thalidomide (a first-generation IMiD) in terms of efficacy and safety in human studies. The key to the therapeutic potential of IMiDs lies in the fact that the drugs have multiple mechanisms of action, which may produce both anti-inflammatory and antitumour effects. These effects are probably contextual, depending both on the cell type and the stimulus involved. Mechanisms associated with IMiD activity include TNF-alpha-inhibitory, T cell costimulatory and antiangiogenic activities. Studies of the mechanisms of action of these drugs are ongoing and will facilitate the continued development of this class of compound in a number of diseases.

  18. Causative and non-causative verbs in studying emotive vocabulary

    Directory of Open Access Journals (Sweden)

    Юлия Николаевна Эбзеева

    2011-12-01

    Full Text Available The article deals with causative and non-causative verbs in describing emotional states. The work reveals the relations among subject of the state, the emotional state and the reasons of this state in the works of contemporary French and English authors.

  19. Ammonium derivatives of chromenones and quinolinones as lead antimicrobial agents

    Indian Academy of Sciences (India)

    Shilpi Gupta; Seema Singh; Abha Kathuria; Manish Kumar; Sweta Sharma; Ram Kumar; Virinder S Parmar; Bharat Singh; Anjali Gupta; Erik Van Der Eycken; Gainda L Sharma; Sunil K Sharma

    2012-03-01

    A series of novel ammonium derivatives were synthesized and examined for their antimicrobial efficacy. Comparison of antimicrobial spectrum revealed that compounds 9, 11, 16 and 23 had strong potential against pathogens in vitro. Cytotoxicity results showed compound 9 to be least toxic, it is non-toxic to A549 and U87 cells in MTT assay and exhibits marginal toxicity (15-20%) to human erythrocytes at a concentration of 1000 g/ml as compared to 100% lysis of cells by 31.25 g/ml of the standard drug amphotericin B. This compound has MIC values in the range of 1.95-31.25 g/disc in DDA against different pathogens and may considered to be an important lead antimicrobial molecule for further exploration.

  20. Substituted urea derivatives: a potent class of antidepressant agents.

    Science.gov (United States)

    Perveen, Shahnaz; Mustafa, Sana; Khan, Muhammad A; Dar, Ahsana; Khan, Khalid M; Voelter, Wolfgang

    2012-05-01

    A series of fourteen (14) N-nitrophenyl-N'-(alkyl/aryl)urea and symmetrical 1,3-disubstituted urea derivatives were synthesized and evaluated for their antidepressant activity in mice. Among them, N-(4-nitrophenyl)-N'-(1'-phenylethyl)urea (1), demonstrated profound antidepressant property as reflected by significant reduction in the immobility time (89.83%), whereas compounds 2-6 showed activity values between 36 to 59% which were also larger than the standard phenelzine. Compounds 7-9 were less effective in reducing the immobility period of mice 26.20 to 31.01%). This variable magnitude of antidepressant activity appears to be related to the position of the nitro group to the parent molecules 1, 2, and 8. Compound 1 with the nitro group at para position showed to be the most effective antidepressant. However, the activity declined, if the nitro is attached to ortho and meta positions.

  1. Antiviral agents derived from novel 1-adamantyl singlet nitrenes.

    Science.gov (United States)

    Kesel, Andreas J; Weiss, Hans-Christoph; Schönleber, Andreas; Day, Craig W; Barnard, Dale L; Detorio, Mervi A; Schinazi, Raymond F

    2012-12-07

    Amantadine constitutes an interesting, diamond crystal lattice-shaped, antivirally active amine with an inhibitory effect on influenza A viruses causing common 'flu' in humans. Unfortunately, amantadine forfeited most of its therapeutic potential because of resistance development in recent influenza A virus isolates. The antiviral efficacy of amantadine congeners can be chemically modified, resulting in re-constitution, improvement and/or extension of antiviral activities mediated by amino-adamantyls. Newly synthesized compounds were evaluated towards HIV type-1 (HIV-1) replication in primary human lymphocytes. One N-phenacyl amantadine derivative was investigated for inhibiting the in vitro replication of respiratory viruses (influenza A viruses, influenza B virus, human parainfluenza virus type 3 and severe acute respiratory syndrome coronavirus). Two ketone-stabilized 1-adamantyl singlet nitrenes were discovered serendipitously. To our best knowledge these are the first persistently stable nitrenes to be reported. Their structure was proved by determining the X-ray single crystal structure of one hydrolytic elaboration product. This salt adduct revealed an incommensurately modulated crystal structure, which was solved by extensive computational refinement. We could show that ketone-stabilized 1-adamantyl singlet nitrenes are versatile synthons for the synthesis of antiviral drug candidates. An amantadine-folate conjugate was inhibitory on HIV-1 replication in primary human lymphocytes, and one N-phenacyl amantadine derivative was inhibitory towards low pathogenic avian influenza A virus (H5N1) replication in vitro. These results indicate that the aromatic-aliphatic ketone-stabilized 1-adamantyl singlet nitrenes, beyond being of fundamental interest in organic chemistry, represent versatile synthons for the synthesis of new amantadine-related potentially antiviral drugs.

  2. A review of the Mycrocylus ulei Ascomycetes fungus, causative agent of South American rubber-leaf blight Revisión sobre el hongo Microcyclus ulei, agente causal del mal suramericano de la hoja del caucho

    Directory of Open Access Journals (Sweden)

    Ancízar Aristizábar Fabio

    2006-12-01

    Full Text Available The Microcyclus ulei Ascomycetes fungus is the causal agent of south-American leaf blight (SALB, this being one of the most important diseases affecting the natural rubber tree (Hevea brasiliensis in Latina-America and has been responsible for numerous economic losses. This fungus has presented high physiological variability, suggesting its great adaptability. HCN tolerance has been described as being one of the mechanisms associated with its virulence. Resistant Hevea clones have been obtained by genetic improvement; however, the mechanisms associated with this are still not well known. Greater knowledge of this pathogen will lead to developing new control strategies and better understanding of the mechanisms associated with host resistance. Key words: Microcyclus ulei, SALB, Hevea brasiliensis.El hongo ascomycete Microcyclus ulei es el agente causal del SALB que es una de las enfermedades más importan­tes del árbol de caucho natural (Hevea brasiliensis en América Latina y ha sido responsable de numerosas pérdidas económicas. Este hongo ha presentado alta variabilidad fisiológica y se sugiere su alta adaptabilidad, dentro de los mecanismos asociados a su virulencia se ha descrito la tolerancia al HCN. Se han obtenido clones de Hevea resistentes mediante mejoramiento genético, sin embargo, aun no son bien conocidos los mecanismos asociados a ésta. Un mayor conocimiento de este patógeno permitirá el desarrollo de nuevas estrategias de control así como el mayor entendimiento de los mecanismos asociados a resistencia del hospedero. Palabras clave: Microcyclus ulei, SALB, Hevea brasiliensis.

  3. Risk Minimization and Optimal Derivative Design in a Principal Agent Game

    CERN Document Server

    Horst, U

    2007-01-01

    We consider the problem of Adverse Selection and optimal derivative design within a Principal-Agent framework. The principal's income is exposed to non-hedgeable risk factors arising, for instance, from weather or climate phenomena. She evaluates her risk using a coherent and law invariant risk measure and tries minimize her exposure by selling derivative securities on her income to individual agents. The agents have mean-variance preferences with heterogeneous risk aversion coefficients. An agent's degree of risk aversion is private information and hidden to the principal who only knows the overall distribution. We show that the principal's risk minimization problem has a solution and illustrate the effects of risk transfer on her income by means of two specific examples. Our model extends earlier work of Barrieu and El Karoui (2005) and Carlier, Ekeland and Touzi (2007).

  4. Licensing of Instrumental Case in Hindi/Urdu Causatives

    Directory of Open Access Journals (Sweden)

    Gillian Ramchand

    2011-12-01

    Full Text Available In this paper, I revisit the licensing and interpretation of instrumental case-marked nominals in Hindi/Urdu causative constructions to argue against the hypothesis that the se-marked phrase corresponds to a demoted agent. Rather, I will argue that a more unified analysis of se-phrases can be achieved through an event-structural analysis, in line with the standard interpretation of other adverbials in the syntax. Since the ‘intermediate agent’ interpretation is only possible with indirect causatives in Hindi/Urdu, the event structural analysis proposed here also has implications for the direct vs. indirect causation distinction in the syntax.

  5. Synthesis and biological evaluation of andrographolide derivatives as potent anti-HIV agents

    Institute of Scientific and Technical Information of China (English)

    Bin Wang; Jing Li; Wen Long Huang; Hui Bin Zhang; Hai Qian; Yong Tang Zheng

    2011-01-01

    A series of Andro derivatives were described and evaluated for their anti-HIV activity in vitro. Compound 10 and 16b, of which TI were >10, had some anti-HTV-1 activity in vitro. Therein, compound 10 which was the best potent compound, could serve as a new lead for further development of anti-AIDS agents.

  6. PRENYLATED BENZOIC ACID DERIVATIVES FROM PIPER SPECIES AS SOURCE OF ANTI-INFECTIVE AGENTS

    Directory of Open Access Journals (Sweden)

    Ibrahim Malami

    2012-06-01

    Full Text Available A number of prenylated benzoic acids derivatives with interesting biological activities have been previously isolated and characterized from different species of piperaceae family. Several Piper species contained structurally similar compounds with diverse biological activities such as anti-bacterial, anti-fungal, insecticidal as well as anti-parasitic all of which produces compounds that can be classified as prenylated benzoic acid derivatives. Piper sp has proven to serve as a source of potential anti-infective agents by developing a biosynthetic route to the synthesis of prenylated benzoic acids derivative natural products as their chemical defense system. Despite the frequent isolation of these interesting compounds with strong biological activity, yet none have been taking into consideration for development into therapeutic agents.

  7. Design, synthesis and evaluation of 4-dimethylamine flavonoid derivatives as potential multifunctional anti-Alzheimer agents.

    Science.gov (United States)

    Luo, Wen; Wang, Ting; Hong, Chen; Yang, Ya-Chen; Chen, Ying; Cen, Juan; Xie, Song-Qiang; Wang, Chao-Jie

    2016-10-21

    A new series of 4-dimethylamine flavonoid derivatives were designed and synthesized as potential multifunctional anti-Alzheimer agents. The inhibition of cholinesterase activity, self-induced β-amyloid (Aβ) aggregation, and antioxidant activity by these derivatives was investigated. Most of the compounds exhibited potent acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity. A Lineweaver-Burk plot and molecular modeling study showed that these compounds targeted both the catalytic active site (CAS) and peripheral anionic site (PAS) of AChE. The derivatives showed potent self-induced Aβ aggregation inhibition and peroxyl radical absorbance activity. Moreover, compound 6d significantly protected PC12 neurons against H2O2-induced cell death at low concentrations. Thus, these compounds could become multifunctional agents for further development for the treatment of AD. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. Recognising Top-Down Causation

    CERN Document Server

    Ellis, George F R

    2012-01-01

    One of the basic assumptions implicit in the way physics is usually done is that all causation flows in a bottom up fashion, from micro to macro scales. However this is wrong in many cases in biology, and in particular in the way the brain functions. Here I make the case that it is also wrong in the case of digital computers - the paradigm of mechanistic algorithmic causation - and in many cases in physics, ranging from the origin of the arrow of time to the process of state vector preparation. I consider some examples from classical physics, as well as the case of digital computers, and then explain why this is possible without contradicting the causal powers of the underlying microphysics. Understanding the emergence of genuine complexity out of the underlying physics depends on recognising this kind of causation.

  9. View of Causation for CSCW

    DEFF Research Database (Denmark)

    Christensen, Lars R.; Bertelsen, Olav W.

    2015-01-01

    In this chapter, we attempt to achieve a better understanding of how cooperative work is partly accomplished by virtue of the actors’ manipulation and control of causal relationships central to their material field of work. Previous CSCW studies have not focused extensively on causation in cooper......In this chapter, we attempt to achieve a better understanding of how cooperative work is partly accomplished by virtue of the actors’ manipulation and control of causal relationships central to their material field of work. Previous CSCW studies have not focused extensively on causation...

  10. Synthesis and biological evaluation of the pirfenidone derivatives as antifibrotic agents.

    Science.gov (United States)

    Ma, Zhen; Pan, Youlu; Huang, Wenhai; Yang, Yewei; Wang, Zunyuan; Li, Qin; Zhao, Yin; Zhang, Xinyue; Shen, Zhengrong

    2014-01-01

    A total of 24 pirfenidone derivatives were designed, synthesized and evaluated for their inhibitory activity against the human lung fibroblast cell line MRC-5. These compounds showed the remarkable proliferation inhibition against MRC-5 compared to pirfenidone as the positive control. The possible mechanism of this kind of derivatives as antifibrotic agents was explored. The molecular docking and p38 binding affinity assays demonstrated that the antifibrotic potential of the pirfenidone derivatives was possibly through the inhibition of p38 MAPK signaling pathway. The data from this study suggested that p38 might be a potential therapeutic target for the new generation antifibrotics. All the pirfenidone derivatives are reported here for the first time.

  11. Design and synthesis of novel soluble 2,5-diketopiperazine derivatives as potential anticancer agents.

    Science.gov (United States)

    Liao, Shengrong; Qin, Xiaochu; Li, Ding; Tu, Zhengchao; Li, Jinsheng; Zhou, Xuefeng; Wang, Junfeng; Yang, Bin; Lin, Xiuping; Liu, Juan; Yang, Xianwen; Liu, Yonghong

    2014-08-18

    Non-protected 2,5-diketopiperazine derivatives have poor solubility thus with negative impact on their bioavailability. In the present study, twenty-one novel soluble mono-protected, and three non-protected 2,5-diketopiperazine derivatives were designed and synthesized. Their anticancer activity to ten cell lines were evaluated by using CCK8 assay, and the results showed that about half of the mono-protected derivatives had broad-spectrum anticancer activity. Among allyl-protected derivatives, compound 4m had strong activity to all the cell lines (IC50 = 0.5-4.5 μM), especially to the cancer cell lines U937 (IC50 = 0.5 μM) and K562 (IC50 = 0.9 μM). Compound 4m could become a lead compound for further development for anticancer agents.

  12. Molecular docking of ZSTK474 derivatives as potential PI3K-delta inhibitory agents

    Directory of Open Access Journals (Sweden)

    Liudmyla K. Sviatenko

    2014-12-01

    Full Text Available The phosphatidylinositol 3-kinase delta (PI3Kd controls a range of cellular processes. Its overexpression is found in many human tumors. PI3Kd inhibitors are potential anticancer agents and anti-inflammatory agents for treatment of rheumatoid arthritis. Derivatives of ZSTK474, an effective inhibitor of PI3Kd, were screened virtually by computational docking for inhibitory activity towards PI3Kd. Some of modeled compounds showed better docking energies than ZSTK474 indicating that the former could be potent enzyme inhibitors. Additional binding energy was provided by extra ligand-protein interactions. Substituents in morpholine and benzimidazole rings cause increase and decrease of ligand-protein binding, respectively. Energetically favorable ZSTK474 derivatives satisfy Lipinski’s Rule of five which testifies to their druglikeness (absorption, distribution, metabolism and excretion and possible pharmacological activity.

  13. Synthesis and biological activity of trans-tiliroside derivatives as potent anti-diabetic agents.

    Science.gov (United States)

    Zhu, Yujin; Zhang, Yanjun; Liu, Yi; Chu, Hongwan; Duan, Hongquan

    2010-12-10

    A set of novel trans-tiliroside derivatives were synthesized. The structures of the derivatives were identified by their IR, 1H-NMR, and MS spectra analysis. Their anti-diabetic activities were evaluated on the insulin resistant (IR) HepG2 cell model. As a result, compounds 7a, 7c, 7h, and trans-tiliroside exhibited significant glucose consumption-enhancing effects in IR-HepG2 cells compared with the positive control (metformin). This research provides useful clues for further design and discovery of anti-diabetic agents.

  14. Synthesis and Biological Activity of trans-Tiliroside Derivatives as Potent Anti-Diabetic Agents

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2010-12-01

    Full Text Available A set of novel trans-tiliroside derivatives were synthesized. The structures of the derivatives were identified by their IR, 1H-NMR, and MS spectra analysis. Their anti-diabetic activities were evaluated on the insulin resistant (IR HepG2 cell model. As a result, compounds 7a, 7c, 7h, and trans-tiliroside exhibited significant glucose consumption-enhancing effects in IR-HepG2 cells compared with the positive control (metformin. This research provides useful clues for further design and discovery of anti-diabetic agents.

  15. Synthesis, Antifungal Activities and Qualitative Structure Activity Relationship of Carabrone Hydrazone Derivatives as Potential Antifungal Agents

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2014-03-01

    Full Text Available Aimed at developing novel fungicides for relieving the ever-increasing pressure of agricultural production caused by phytopathogenic fungi, 28 new hydrazone derivatives of carabrone, a natural bioactive sesquisterpene, in three types were designed, synthesized and their antifungal activities against Botrytis cinerea and Colletotrichum lagenarium were evaluated. The result revealed that all the derivatives synthesized exhibited considerable antifungal activities in vitro and in vivo, which led to the improved activities for carabrone and its analogues and further confirmed their potential as antifungal agents.

  16. Crocetin: an agent derived from saffron for prevention and therapy for cancer

    OpenAIRE

    Gutheil, William G.; Reed, Gregory; Ray, Amitabha; Dhar, Animesh

    2012-01-01

    Cancer is one of the leading causes of death in the United States and accounts for approximately 8 million deaths per year worldwide. Although there is an increasing number of therapeutic options available for patients with cancer, their efficacy is time-limited and non-curative. Approximately 50-60% of cancer patients in the United States utilize agents derived from different parts of plants or nutrients (complementary and alternative medicine), exclusively or concurrently with traditional t...

  17. Evidence-based toxicology: a comprehensive framework for causation.

    Science.gov (United States)

    Guzelian, Philip S; Victoroff, Michael S; Halmes, N Christine; James, Robert C; Guzelian, Christopher P

    2005-04-01

    This paper identifies deficiencies in some current practices of causation and risk evaluation by toxicologists and formulates an evidence-based solution. The practice of toxicology focuses on adverse health events caused by physical or chemical agents. Some relations between agents and events are identified risks, meaning unwanted events known to occur at some frequency. However, other relations that are only possibilities--not known to occur (and may never be realized)--also are sometimes called risks and are even expressed quantitatively. The seemingly slight differences in connotation among various uses of the word 'risk' conceal deeply philosophic differences in the epistemology of harm. We label as 'nomological possibilities' (not as risks) all predictions of harm that are known not to be physically or logically impossible. Some of these nomological possibilities are known to be causal. We term them 'epistemic'. Epistemic possibilities are risks. The remaining nomological possibilities are called 'uncertainties'. Distinguishing risks (epistemic relationships) from among all nomological possibilities requires knowledge of causation. Causality becomes knowable when scientific experiments demonstrate, in a strong, consistent (repeatable), specific, dose-dependent, coherent, temporal and predictive manner that a change in a stimulus determines an asymmetric, directional change in the effect. Many believe that a similar set of characteristics, popularly called the 'Hill Criteria', make it possible, if knowledge is robust, to infer causation from only observational (nonexperimental) studies, where allocation of test subjects or items is not under the control of the investigator. Until the 1980s, medical decisions about diagnosis, prevention, treatment or harm were often made authoritatively. Rather than employing a rigorous evaluation of causal relationships and applying these criteria to the published knowledge, the field of medicine was dominated by authority

  18. Acetylcholinesterase in Biofouling Species: Characterization and Mode of Action of Cyanobacteria-Derived Antifouling Agents.

    Science.gov (United States)

    Almeida, Joana R; Freitas, Micaela; Cruz, Susana; Leão, Pedro N; Vasconcelos, Vitor; Cunha, Isabel

    2015-07-24

    Effective and ecofriendly antifouling (AF) compounds have been arising from naturally produced chemicals. The objective of this study is to use cyanobacteria-derived agents to investigate the role of acetylcholinesterase (AChE) activity as an effect and/or mode of action of promising AF compounds, since AChE inhibitors were found to inhibit invertebrate larval settlement. To pursue this objective, in vitro quantification of AChE activity under the effect of several cyanobacterial strain extracts as potential AF agents was performed along with in vivo AF (anti-settlement) screening tests. Pre-characterization of different cholinesterases (ChEs) forms present in selected tissues of important biofouling species was performed to confirm the predominance of AChE, and an in vitro AF test using pure AChE activity was developed. Eighteen cyanobacteria strains were tested as source of potential AF and AChE inhibitor agents. Results showed effectiveness in selecting promising eco-friendly AF agents, allowing the understanding of the AF biochemical mode of action induced by different compounds. This study also highlights the potential of cyanobacteria as source of AF agents towards invertebrate macrofouling species.

  19. Lead optimization through VLAK protocol: new annelated pyrrolo-pyrimidine derivatives as antitumor agents.

    Science.gov (United States)

    Lauria, Antonino; Patella, Chiara; Abbate, Ilenia; Martorana, Annamaria; Almerico, Anna Maria

    2012-09-01

    The chemometric protocol VLAK was applied to predict improvement of the biological activity of pyrrolo-pyrimidine derivatives as anticancer agents, by using the NCI ACAM Database as depository of antitumor drugs with a known mechanism of action. Among the selected compounds two of these showed a good increase in the antitumor activity. These new pyrrolo-pyrimidine compounds were demonstrated effective against the full panels of NCI DTP tumour human cell lines. The derivative 8-[3-(piperidino)propyl]-4,10-dimethyl-9-phenyl-6-(methylsulfanyl)-3,4-dihydropyrimido[1,2-c]pyrrolo[3,2-e]pyrimidin-2(8H)-one reveled efficacious against the leukemia subpanel, in particular the RPMI cell line resulted the most sensitive (pGI(50) = 6.68). Moreover the derivative 7-(3-Chloropropyl)-9-methyl-5-(methylsulfanyl)-8-phenyl-3H-imidazo[1,2-c]pyrrolo[3,2-e]pyrimidin-2(7H)-one showed a good antitumor activity against the leukemia subpanel with a low cytotoxic activity, above all against the HCT11 human tumour cell line. The VLAK protocol revealed a good method to design new molecules with good antitumor activity, starting from low active compounds. Moreover this protocol focused on the pyrrolo-pyrimidine derivatives as useful starting point for further development to obtain more potent antitumor agents.

  20. Can Some Marine-Derived Fungal Metabolites Become Actual Anticancer Agents?

    Science.gov (United States)

    Gomes, Nelson G M; Lefranc, Florence; Kijjoa, Anake; Kiss, Robert

    2015-06-19

    Marine fungi are known to produce structurally unique secondary metabolites, and more than 1000 marine fungal-derived metabolites have already been reported. Despite the absence of marine fungal-derived metabolites in the current clinical pipeline, dozens of them have been classified as potential chemotherapy candidates because of their anticancer activity. Over the last decade, several comprehensive reviews have covered the potential anticancer activity of marine fungal-derived metabolites. However, these reviews consider the term "cytotoxicity" to be synonymous with "anticancer agent", which is not actually true. Indeed, a cytotoxic compound is by definition a poisonous compound. To become a potential anticancer agent, a cytotoxic compound must at least display (i) selectivity between normal and cancer cells (ii) activity against multidrug-resistant (MDR) cancer cells; and (iii) a preferentially non-apoptotic cell death mechanism, as it is now well known that a high proportion of cancer cells that resist chemotherapy are in fact apoptosis-resistant cancer cells against which pro-apoptotic drugs have more than limited efficacy. The present review thus focuses on the cytotoxic marine fungal-derived metabolites whose ability to kill cancer cells has been reported in the literature. Particular attention is paid to the compounds that kill cancer cells through non-apoptotic cell death mechanisms.

  1. Novel quinoxaline 1,4-di-N-oxide derivatives as new potential antichagasic agents.

    Science.gov (United States)

    Torres, Enrique; Moreno-Viguri, Elsa; Galiano, Silvia; Devarapally, Goutham; Crawford, Philip W; Azqueta, Amaia; Arbillaga, Leire; Varela, Javier; Birriel, Estefanía; Di Maio, Rossanna; Cerecetto, Hugo; González, Mercedes; Aldana, Ignacio; Monge, Antonio; Pérez-Silanes, Silvia

    2013-08-01

    As a continuation of our research and with the aim of obtaining new agents against Chagas disease, an extremely neglected disease which threatens 100 million people, eighteen new quinoxaline 1,4-di-N-oxide derivatives have been synthesized following the Beirut reaction. The synthesis of the new derivatives was optimized through the use of a new and more efficient microwave-assisted organic synthetic method. The new derivatives showed excellent in vitro biological activity against Trypanosoma cruzi. Compound 17, which was substituted with fluoro groups at the 6- and 7-positions of the quinoxaline ring, was the most active and selective in the cytotoxicity assay. The electrochemical study showed that the most active compounds, which were substituted by electron-withdrawing groups, possessed a greater ease of reduction of the N-oxide groups.

  2. Preparation and in vitro evaluation of benzylsulfanyl benzoxazole derivatives as potential antituberculosis agents.

    Science.gov (United States)

    Klimesová, Vera; Kocí, Jan; Waisser, Karel; Kaustová, Jarmila; Möllmann, Ute

    2009-05-01

    A set of 2-benzylsulfanyl derivatives of benzoxazole was synthesized and evaluated for their in vitro antimycobacterial activity against Mycobacterium tuberculosis, non-tuberculous mycobacteria and multidrug-resistant M. tuberculosis. The activities were expressed as the minimum inhibitory concentration (MIC) in mmol/L. The substances showed similar activity against all tested strains. The lead compounds in the set, dinitro derivatives exhibited significant activity against both sensitive and resistant strains of M. tuberculosis and also against non-tuberculous mycobacteria. To facilitate drug design of benzoxazole as potential antituberculosis agent, we have explored the quantitative structure-activity relationship (QSAR). We demonstrated that lower lipophilicity has significant contribution to activity. Dinitrobenzylsulfanyl derivative of benzoxazole represents the promising small-molecule synthetic antimycobacterials.

  3. Recent developments of C-4 substituted coumarin derivatives as anticancer agents.

    Science.gov (United States)

    Dandriyal, Jyoti; Singla, Ramit; Kumar, Manvendra; Jaitak, Vikas

    2016-08-25

    Cancer is a prominent cause of death in global. Currently, the numbers of drugs that are in clinical practice are having a high prevalence of side effect and multidrug resistance. Researchers have made an attempt to expand a suitable anticancer drug that has no MDR and side effect. Coumarin scaffold became an attractive subject due to their broad spectrum of pharmacological activities. Coumarin derivatives extensively explored for anticancer activities as it possesses minimum side effect along with multi-drug reversal activity. Coumarin derivatives can act by various mechanisms on different tumor cell lines depending on substitution pattern of the core structure of coumarin. Substitution on coumarin nucleus leads to the search for more potent compounds. In this review, we have made an effort to give a synthetic strategy for the preparation of C-4 substituted coumarin derivatives as anticancer agents based on their mechanism of action and also discuss the SAR of the most active compound.

  4. Synthetic biology and genetic causation.

    Science.gov (United States)

    Oftedal, Gry; Parkkinen, Veli-Pekka

    2013-06-01

    Synthetic biology research is often described in terms of programming cells through the introduction of synthetic genes. Genetic material is seemingly attributed with a high level of causal responsibility. We discuss genetic causation in synthetic biology and distinguish three gene concepts differing in their assumptions of genetic control. We argue that synthetic biology generally employs a difference-making approach to establishing genetic causes, and that this approach does not commit to a specific notion of genetic program or genetic control. Still, we suggest that a strong program concept of genetic material can be used as a successful heuristic in certain areas of synthetic biology. Its application requires control of causal context, and may stand in need of a modular decomposition of the target system. We relate different modularity concepts to the discussion of genetic causation and point to possible advantages of and important limitations to seeking modularity in synthetic biology systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Adding pharmacogenomics to the development of new marine-derived anticancer agents

    Directory of Open Access Journals (Sweden)

    Aracil Miguel

    2006-01-01

    Full Text Available Abstract Nature has always been a highly productive tool in the development of anticancer therapies. Renewed interest in the potential of this tool has recently been sparked by the realization that the marine ecosystem can be used for the discovery and development of new compounds with clinical potential in advanced resistant tumors. These compounds can be incorporated into combination approaches in a chronic therapy scenario. Our marine anticancer program is using the sea to develop new agents with activity in resistant solid tumors and to identify new cellular targets for therapeutic intervention. This review describes the integration of different pharmacogenomic tools in the development of Yondelis™, Aplidin® and Kahalalide F, three marine-derived compounds currently in Phase II or III development. Our results are reinforcing the targeted selectivity of these agents and opening the gates for customized therapies in cancer patients in the near future.

  6. ONIOM studies of interaction between single-walled carbon nanotube and gallates derivatives as anticancer agents

    Directory of Open Access Journals (Sweden)

    Nosrat Madadi Mahani

    2017-01-01

    Full Text Available Objective(s: The novel 7-hydroxycoumarinyl gallates derivatives are detected in many pharmaceutical compounds like anticancer and antimicrobial agents. Whereas carbon nanotubes (CNTs have been discussed for nanomedicine applications and in particular as drug delivery systems. The capability of armchair (5, 5 SWCNT -based drug delivery system in the therapy of anticancer has been investigated by quantum mechanics/molecular mechanics method.Materials and Methods: Theoretical investigation of the interaction between armchair (5, 5 SWCNT with gallates derivatives has been fulfilled by quantum mechanics/molecular mechanics (QM/MM method by ONIOM2 (DFT: UFF using the program of GAUSSIAN 03 suite.Results: The results derived from this study, demonstrate  that armchair (5, 5 SWCNT has weak interaction that these interactions contain Vander Waals interactions and indicated clearly that these systems have relatively low durability and so armchair (5, 5 SWCNT is appropriate drug delivery that have been investigated for anti-cancer drug.Conclusion: Analysis of ONIOM2 calculations and the interaction energies of the armchair (5, 5 SWCNT and gallates derivatives represented that this carrier can be utilized to improve the biological and anti-cancer activity of gallates derivatives.

  7. Salicylic acid and some of its derivatives as antibacterial agents for viscose fabric.

    Science.gov (United States)

    Kantouch, A; El-Sayed, A Atef; Salama, M; El-Kheir, A Abou; Mowafi, S

    2013-11-01

    Salicylic acid and three of its derivatives were used to provide antibacterial properties to viscose fabrics. The four bactericides used were bonded to the viscose fabrics using epichlorohydrin or polymer binders. Optimization of the salicylic acid and its derivatives as well as the concentration of polymers was reported. The ability of the polymer binders to attract and bind the four bactericides was observed. The overall results show that the antibacterial reactivity of salicylic acid and its derivatives are in the following order 5-bromosalicylic acid>salicylic acid>5-chlorosalicylic acid>4-chlorosalicylic acid. Using epichlorohydrin as a binding agent, unfortunately, inhibits the bactericidal activity of the four bactericides. The FTIR study concludes that the reaction between salicylic acid as well as its derivatives with epichlorohydrin takes place through the phenolic group of the acids. The unexpected deterioration in the bactericidal properties of salicylic acid and its derivatives as a result of the treatment with epichlorohydrin could be due to the nature of interaction between the epichlorohydrin molecule and the acids molecules. PVP and PU show superior ability to sustain the four bactericides used even after 10 washing cycles.

  8. Peroxidase catalyzed nitration of tryptophan derivatives. Mechanism, products and comparison with chemical nitrating agents.

    Science.gov (United States)

    Sala, Alberto; Nicolis, Stefania; Roncone, Raffaella; Casella, Luigi; Monzani, Enrico

    2004-07-01

    The enzymatic nitration of tryptophan derivatives by oxidation of nitrite has been studied using lactoperoxidase and horseradish peroxidase, and compared with the chemical nitration produced by nitrogen dioxide and peroxynitrite. HPLC, mass spectra and NMR analysis of the mixture of products clearly show that nitration occurs at position 4-, 6-, 7-, and N1 of the indole ring, and nitrosation at position N1. Kinetic studies performed on peroxidase/NO2-/H2O2 systems showed substrate saturation behavior with all the tryptophan derivatives employed. The rate dependence on nitrite concentration was found to be linear with horseradish peroxidase while it exhibited saturation behavior with lactoperoxidase. The composition of the product mixture depends on the nitrating agent. While the production of 4-nitro, 6-nitro, 7-nitro and N1-nitro derivatives follows a similar trend, indicating that they are formed according to a similar mechanism, the ratio between the N1-nitroso derivative and other derivatives depends markedly on the nitrite concentration when tryptophan modification is performed by the peroxidase/H2O2/nitrite systems. Analysis of the data indicates that at low nitrite concentration the enzymatic reaction occurs through the classical peroxidase cycle. At high nitrite concentration the reaction proceeds through a different intermediate that we assume to be a protein bound peroxynitrite species.

  9. Spasmolytic agents. 2. 1,2,3,4-Tetrahydro-2-naphthylamine derivatives.

    Science.gov (United States)

    Kanao, M; Hashizume, T; Ichikawa, Y; Irie, K; Isoda, S

    1982-11-01

    N-[(Benzoyloxy)alkyl]-1,2,3,4-tetrahydro-2-naphthylamine derivatives were synthesized from 1,2,3,4-tetrahydro-2-naphthylamines and evaluated for their spasmolytic. Some of these compounds showed a nerve-selective effect on colon rather than stomach in anesthetized dogs and were found to be equal to or more active than the reference drug (mebeverine). The biological data have indicated some structure-activity relationships. Among these compounds, N-ethyl-N-[6-(3,4-dimethoxybenzoyl)oxy]hexyl]-1,2,3,4-tetrahydro-6-methoxy-2- napththylamine hydrochloride (63) was found to be the most active spasmolytic agent.

  10. Synthesis and Biological Evaluation of Novel Tricyclic Oximino Derivatives as Antitumor Agents

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A series of novel alkylthio/sulfinyl-8H-thieno[2,3-b]pyrrolizin-8-oximino derivatives Ⅴ1-Ⅷ15 were designed and synthesized as antitumor agents. Their structures were confirmed using IR, 1H NMR, elemental analysis,and MS. The antitumor activities of all the target compounds were tested by the MTT method in vitro against Bel-7402,HT-1080, SGC-7901, and A549 Cell Lines. Among them, compound Ⅵ9 displayed a promising antitumor activity superior to that of Cisplatin.

  11. Evolution in medicinal chemistry of ursolic acid derivatives as anticancer agents.

    Science.gov (United States)

    Chen, Haijun; Gao, Yu; Wang, Ailan; Zhou, Xiaobin; Zheng, Yunquan; Zhou, Jia

    2015-03-06

    Currently, there is a renewed interest in common dietaries and plant-based traditional medicines for the prevention and treatment of cancer. In the search for potential anticancer agents from natural sources, ursolic acid (UA), a pentacyclic triterpenoid widely found in various medicinal herbs and fruits, exhibits powerful biological effects including its attractive anticancer activity against various types of cancer cells. However, the limited solubility, rapid metabolism and poor bioavailability of UA restricted its further clinical applications. In the past decade, with substantial progress toward the development of new chemical entities for the treatment of cancer, numerous UA derivatives have been designed and prepared to overcome its disadvantages. Despite extensive effort, discovery of effective UA derivatives has so far met with only limited success. This review summarizes the current status of the structural diversity and evolution in medicinal chemistry of UA analogues and provides a detailed discussion of future direction for further research in the chemical modifications of UA.

  12. Discovery and development of natural product-derived chemotherapeutic agents based on a medicinal chemistry approach.

    Science.gov (United States)

    Lee, Kuo-Hsiung

    2010-03-26

    Medicinal plants have long been an excellent source of pharmaceutical agents. Accordingly, the long-term objectives of the author's research program are to discover and design new chemotherapeutic agents based on plant-derived compound leads by using a medicinal chemistry approach, which is a combination of chemistry and biology. Different examples of promising bioactive natural products and their synthetic analogues, including sesquiterpene lactones, quassinoids, naphthoquinones, phenylquinolones, dithiophenediones, neo-tanshinlactone, tylophorine, suksdorfin, DCK, and DCP, will be presented with respect to their discovery and preclinical development as potential clinical trial candidates. Research approaches include bioactivity- or mechanism of action-directed isolation and characterization of active compounds, rational drug design-based modification and analogue synthesis, and structure-activity relationship and mechanism of action studies. Current clinical trial agents discovered by the Natural Products Research Laboratories, University of North Carolina, include bevirimat (dimethyl succinyl betulinic acid), which is now in phase IIb trials for treating AIDS. Bevirimat is also the first in a new class of HIV drug candidates called "maturation inhibitors". In addition, an etoposide analogue, GL-331, progressed to anticancer phase II clinical trials, and the curcumin analogue JC-9 is in phase II clinical trials for treating acne and in development for trials against prostate cancer. The discovery and development of these clinical trial candidates will also be discussed.

  13. Comparison of enamel matrix derivative versus formocresol as pulpotomy agents in the primary dentition.

    Science.gov (United States)

    Sabbarini, Jumana; Mohamed, Ahmed; Wahba, Nadia; El-Meligy, Omar; Dean, Jeffrey

    2008-03-01

    The purpose of this study was to compare the clinical and radiographic success rates of two different pulpotomy agents: one novel agent, the biologically active odontogenic protein enamel matrix derivative (EMD) versus formocresol (FC). A randomized, single-blind, split-mouth study was used with a sample of 15 children aged 4 to 7 years (mean age, 5 +/- 0.73 years). A total of 15 pairs of teeth, 1 pair per child, were selected for treatment. One tooth from each pair was randomly assigned to either the EMD pulpotomy group or the FC pulpotomy group. All teeth were followed up clinically and radiographically at 2, 4, and 6 months. After 6 months, the clinical success rates for the FC and EMD groups were 67% and 93%, respectively. Although most likely clinically relevant, the clinical success rate difference after 6 months was not statistically significant. After 6 months, the radiographic success rates for the FC and EMD groups were 13% and 60 %, respectively. There was a statistically significant difference at p < or = 0.05. The clinical and radiographic assessment of EMD pulpotomized teeth in this study offers preliminary evidence that EMD is a promising material which may be as successful, or more so, than other pulpotomy agents.

  14. Can Some Marine-Derived Fungal Metabolites Become Actual Anticancer Agents?

    Directory of Open Access Journals (Sweden)

    Nelson G. M. Gomes

    2015-06-01

    Full Text Available Marine fungi are known to produce structurally unique secondary metabolites, and more than 1000 marine fungal-derived metabolites have already been reported. Despite the absence of marine fungal-derived metabolites in the current clinical pipeline, dozens of them have been classified as potential chemotherapy candidates because of their anticancer activity. Over the last decade, several comprehensive reviews have covered the potential anticancer activity of marine fungal-derived metabolites. However, these reviews consider the term “cytotoxicity” to be synonymous with “anticancer agent”, which is not actually true. Indeed, a cytotoxic compound is by definition a poisonous compound. To become a potential anticancer agent, a cytotoxic compound must at least display (i selectivity between normal and cancer cells (ii activity against multidrug-resistant (MDR cancer cells; and (iii a preferentially non-apoptotic cell death mechanism, as it is now well known that a high proportion of cancer cells that resist chemotherapy are in fact apoptosis-resistant cancer cells against which pro-apoptotic drugs have more than limited efficacy. The present review thus focuses on the cytotoxic marine fungal-derived metabolites whose ability to kill cancer cells has been reported in the literature. Particular attention is paid to the compounds that kill cancer cells through non-apoptotic cell death mechanisms.

  15. Synthesis and In Vitro Evaluation of New Thiosemicarbazone Derivatives as Potential Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Zafer Asım Kaplancıklı

    2016-01-01

    Full Text Available In an effort to develop potent antimicrobial agents, new thiosemicarbazone derivatives were synthesized via the reaction of 4-[4-(trifluoromethylphenyl]thiosemicarbazide with aromatic aldehydes. The compounds were evaluated for their inhibitory effects on pathogenic bacteria and yeasts using the CLSI broth microdilution method. Microplate Alamar Blue Assay was also carried out to determine the antimycobacterial activities of the compounds against Mycobacterium tuberculosis H37Rv. Among these derivatives, compounds 5 and 11 were more effective against Enterococcus faecalis (ATCC 29212 than chloramphenicol, whereas compounds 1, 2, and 12 and chloramphenicol showed the same level of antibacterial activity against E. faecalis. Moreover, compound 2 and chloramphenicol exhibited the same level of antibacterial activity against Staphylococcus aureus. On the other hand, the most potent anticandidal derivatives were found as compounds 2 and 5. These derivatives and ketoconazole exhibited the same level of antifungal activity against Candida glabrata. According to the Microplate Alamar Blue Assay, the tested compounds showed weak to moderate antitubercular activity.

  16. Evaluation of guar gum derivatives as gelling agents for microbial culture media.

    Science.gov (United States)

    Gangotri, Waikhom; Jain-Raina, Ruchi; Babbar, Shashi B

    2012-05-01

    Guar gum, a galactomannan, has been reported to be an inexpensive substitute of agar for microbial culture media. However, its use is restricted probably because of (1) its highly viscous nature even at high temperatures, making dispensing of the media to Petri plates difficult and (2) lesser clarity of the guar gum gelled media than agar media due to impurities present in guar gum. To overcome these problems, three guar gum derivatives, carboxymethyl guar, carboxymethyl hydroxypropyl guar and hydroxypropyl guar, were tested as gelling agents for microbial growth and differentiation. These were also evaluated for their suitability for other routine microbiological methods, such as, enumeration, use of selective and differential media, and antibiotic sensitivity test. For evaluation purpose, growth and differentiation of eight fungi and eight bacteria grown on the media gelled with agar (1.5%), guar gum (4%) or one of the guar gum derivatives (4%), were compared. All fungi and bacteria exhibited normal growth and differentiation on all these media. Generally, growth of most of the fungi was better on guar gum derivatives gelled medium than on agar medium. The enumeration carried out for Serratia sp. and Pseudomonas aeruginosa by serial dilution and pour plate method yielded similar counts in all the treatments. Likewise, the selective succinate medium, specific for P. aeruginosa, did not allow growth of co-inoculated Bacillus sp. even if gelled with guar gum derivatives. The differential medium, Congo red mannitol agar could not differentiate between Agrobacterium tumefaciens and Rhizobium meliloti on color basis, if gelled with guar gum or any of its derivatives However, for antibiotic sensitivity tests for both Gram-positive and -negative bacteria, guar gum and its derivatives were as effective as agar.

  17. Organic causation of morbid jealousy.

    Science.gov (United States)

    Kuruppuarachchi, K A L A; Seneviratne, A N

    2011-12-01

    This article describes the organic contribution to morbid jealousy. Although the true prevalence of morbid jealousy is unknown, organic factors contribute significantly to its development. We present an assortment of five case histories to highlight the importance of organic causation in this phenomenon. The first two cases portray organic delusional disorder arising as an aftermath of cerebral infarcts. They are both associated with left sided brain lesions. Though organic processes generally respond poorly to treatment, case 3 (patient with head injury), is unusual as it describes a young man whose symptoms resolve on recovering from the effects of a head injury. Likewise, case 4 (patient with a meningioma) who made a complete recovery following surgery, emphasizes the need for early detection of reversible causes. The difficulty in identifying the common substrate for a phenomenon with such a wide variety of causations is amply displayed by the abundance of theories forwarded. The blurred demarcation between normal jealousy and pathological jealousy leads to further uncertainty. The excess representation of morbid jealousy in organic conditions is not enlightened by these theories. Organic pathology, by affecting the higher centers of the brain, may remove the control over instinctual behaviour. Evidence for this is hard to establish but the evolutionary perspective of jealousy akin to that of the animal kingdom alludes to possible explanations.

  18. In search of a cytostatic agent derived from the alkaloid lycorine: synthesis and growth inhibitory properties of lycorine derivatives.

    Science.gov (United States)

    Evdokimov, Nikolai M; Lamoral-Theys, Delphine; Mathieu, Véronique; Andolfi, Anna; Frolova, Liliya V; Pelly, Stephen C; van Otterlo, Willem A L; Magedov, Igor V; Kiss, Robert; Evidente, Antonio; Kornienko, Alexander

    2011-12-01

    As a continuation of our studies aimed at the development of a new cytostatic agent derived from an Amaryllidaceae alkaloid lycorine, we synthesized 32 analogues of this natural product. This set of synthetic analogues included compounds incorporating selective derivatization of the C1 versus C2 hydroxyl groups, aromatized ring C, lactamized N6 nitrogen, dihydroxylated C3-C3a olefin functionality, transposed olefin from C3-C3a to C2-C3 or C3a-C4, and C1 long-chain fatty esters. All synthesized compounds were evaluated for antiproliferative activities in vitro in a panel of tumor cell lines including those exhibiting resistance to proapoptotic stimuli and representing solid cancers associated with dismal prognoses, such as melanoma, glioblastoma, and non-small-cell lung cancer. Most active analogues were not discriminatory between cancer cells displaying resistance or sensitivity to apoptosis, indicating that these compounds are thus able to overcome the intrinsic resistance of cancer cells to pro-apoptotic stimuli. 1,2-Di-O-allyllycorine was identified as a lycorine analogue, which is 100 times more potent against a U373 human glioblastoma model than the parent natural product. Furthermore, a number of synthetic analogues were identified as promising for the forthcoming in vivo studies.

  19. Chiral lactic hydrazone derivatives as potential bioactive antibacterial agents: Synthesis, spectroscopic, structural and molecular docking studies

    Science.gov (United States)

    Noshiranzadeh, Nader; Heidari, Azam; Haghi, Fakhri; Bikas, Rahman; Lis, Tadeusz

    2017-01-01

    A series of novel chiral lactic-hydrazone derivatives were synthesized by condensation of (S)-lactic acid hydrazide with salicylaldehyde derivatives and characterized by elemental analysis and spectroscopic studies (FT-IR, 1H NMR and 13C NMR spectroscopy). The structure of one compound was determined by single crystal X-ray analysis. Antibacterial activity of the synthesized compounds was studied against Staphylococcus aureus, Streptococcus pneumonia, Escherichia coli and Pseudomonas aeruginosa as bacterial cultures by broth microdilution method. All of the synthesized compounds showed good antibacterial activity with MIC range of 64-512 μg/mL. Compounds (S,E)-2-hydroxy-N-(2-hydroxy-5-nitrobenzylidene)propanehydrazide (5) and (S,E)-2-hydroxy-N-((3-hydroxy-5-(hydroxymethyl)-2-methylpyridin-4-yl)propanehydrazide (7) were the most effective antibacterial derivatives against S. aureus and E. coli respectively with a MIC value of 64 μg/mL. Bacterial biofilm formation assay showed that these compounds significantly inhibited biofilm formation of P. aeruginosa. Also, in silico molecular docking studies were performed to show lipoteichoic acid synthase (LtaS) inhibitory effect of lactic hydrazone derivatives. The association between electronic and structural effects of some substituents on the benzylidene moiety and the biological activity of these chiral compounds were studied. Structural studies show that compound with higher hydrogen bonding interactions show higher antibacterial activity. The results show chiral hydrazone derivatives based on lactic acid hydrazide could be used as potential lead compounds for developing novel antibacterial agents.

  20. Novel platinum(IV) complexes conjugated with a wogonin derivative as multi-targeted anticancer agents.

    Science.gov (United States)

    Qin, Xiaodong; Xu, Gang; Chen, Feihong; Fang, Lei; Gou, Shaohua

    2017-04-15

    Platinum-based complexes like cisplatin and oxaliplatin are well known the mainstay of chemotherapy regimens on clinic. Wogonin, a natural product that possesses wide biological activities, is now in phase I clinical test as an anticancer agent in China. Herein reported are a series of novel Pt(IV) complexes that conjugated a wogonin derivative (compound 3) to the axial position via a linker group. After being tethered to the platinum(IV) complexes, the wogonin derivative provided multiple anticancer effects, especially in compound 10, a fusion containing wogonin and cisplatin units. Compound 10 not only inherited the genotoxicity from cisplatin, but also obtained the COX inhibitory property from the wogonin derivative. Further mechanistic investigation revealed that compound 10 caused the accumulation of ROS, decreased the mitochondrial membrane potential (ΔΨm) and then activated the p53 pathway. Overall, the research demonstrates that the "integrative" prodrug can be an effective strategy to promote the anticancer potency of Pt-based drugs for cancer treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Synthesis and Biological Activity of Isoflavone Derivatives from Chickpea as Potent Anti-Diabetic Agents

    Directory of Open Access Journals (Sweden)

    Pengshou Li

    2015-09-01

    Full Text Available A set of novel isoflavone derivatives from chickpea were synthesized. The structures of derivatives were identified by proton nuclear magnetic resonance (1H-NMR, carbon-13 (13C-NMR and mass spectrometry (MS spectral analyses. Their anti-diabetic activities were evaluated using an insulin-resistant (IR HepG2 cell model. Additionally, the structure-activity relationships of these derivatives were briefly discussed. Compounds 1c, 2h, 3b, and 5 and genistein exhibited significant glucose consumption-enhancing effects in IR-HepG2 cells. In addition, the combinations of genistein, 2h, and 3b (combination 6 and of 3b, genistein, and 1c (combination 10 exhibited better anti-diabetic activity than the individual compounds. At the same dosage, there was no difference in effect between the combination 10 and the positive control (p > 0.05. Aditionally, we found the differences between the combination 10 and combination 6 for the protective effect of HUVEC (human umbilical vein endothelial cells under high glucose concentration. The protective effects of combination 10 was stronger than combination 6, which suggested that combination 10 may have a better hypoglycemic activity in future studies. This study provides useful clues for the further design and discovery of anti-diabetic agents.

  2. Synthesis and Pharmacological Evaluation of Novel Benzenesulfonamide Derivatives as Potential Anticonvulsant Agents

    Directory of Open Access Journals (Sweden)

    Zhiming Wang

    2015-09-01

    Full Text Available A novel series of benzenesulfonamide derivatives containing 4-aminobenzenesul-fonamide and α-amides branched valproic acid or 2,2-dimethylcyclopropanecarboxylic acid moieties were synthesized and screened for their anticonvulsant activities in mice maximal electroshock seizure (MES and subcutaneous pentylenetetrazole (scPTZ test. The activity experimental study showed that 2,2-dipropyl-N1-(4-sulfamoylphenylmalonamide (18b had the lowest median effective dose (ED50 of 16.36 mg/kg in MES test, and 2,2-dimethyl-N-(4-sulfamoylphenylcyclopropane-1,1-dicarboxamide (12c had the lowest ED50 of 22.50 mg/kg in scPTZ test, which resulted in the protective indexe (PI of 24.8 and 20.4, respectively. These promising data suggest the new compounds have good potential as new class of anticonvulsant agents with high effectiveness and low toxicity for the treatment of epilepsy.

  3. Synthesis and biological evaluation of some novel quinoxaline derivatives as anticonvulsant agents.

    Science.gov (United States)

    Elhelby, Abdelghany Aly; Ayyad, Rezk Rezk; Zayed, Mohamed Fathalla

    2011-01-01

    In view of their expected anticonvulsant activity, some new derivatives of quinonxaline (V1-7) were designed and synthesized by condensation of different aromatic aldehydes with 2-(2-oxo-3-phenylquinoxalin-1(2H)-yl)acetohydrazide (IV). All synthesized compounds were isolated and confirmed by IR, 1H-NMR, MS, elemental analysis and then tested as anticonvulsant agents. Compound V3 and V1 showed the highest anticonvulsant effect with anticonvulsant potency relative to phenobarbital sodium of 0.8 and 0.75 whereas compound V5 exhibited the lowest relative potency of 0.09. The other compounds showed variable activity between these values as follows: V2 = 0.19, V4 = 0.41, V6 = 0.1 and V7 = 0.15. All compounds showed less activity than the reference compound phenobarbital. But the compounds provided a basis for further optimization.

  4. Synthesis and in vitro antitumor activity of substituted quinazoline and quinoxaline derivatives: search for anticancer agent.

    Science.gov (United States)

    Noolvi, Malleshappa N; Patel, Harun M; Bhardwaj, Varun; Chauhan, Ankit

    2011-06-01

    The synthesis of some 2-furano-4(3H)-quinazolinones, diamides (open ring quinazolines), quinoxalines and their biological evaluation as antitumor agents using National Cancer Institute (NCI) disease oriented antitumor screen protocol are investigated. Among the synthesize compounds, seventeen compounds were granted NSC code and screened at National Cancer Institute (NCI), USA for anticancer activity at a single high dose (10(-5) M) in full NCI 60 cell panel. Among the selected compounds, 3-(2-chloro benzylideneamine)-2-(furan-2-yl) quinazoline-4(3h)-one 21 was found to be the most active candidate of the series at five dose level screening against Ovarian OVCAR-4 and Non-small cell lung cancer NCI-H522 with GI50 1.82 & 2.14 μM respectively. Rational approach and QSAR techniques enabled the understanding of the pharmacophoric requirement for quinazoline, diamides and quinoxaline derivatives.

  5. Quantitative structure-activity relationship study on some benzodiazepine derivatives as anti-Alzheimer agents.

    Science.gov (United States)

    Debnath, Bikash; Gayen, Shovanlal; Basu, Anindya; Srikanth, Kolluru; Jha, Tarun

    2004-12-01

    A QSAR study was performed in an attempt to explore the pharmacophore of some benzodiazepine derivatives as anti-Alzheimer agents for the inhibition of gamma-secretase. The study, which used the electrotopological state atom (ETSA) index, which encodes electronic and topological information, reveals the importance of two phenyl rings-one substituted and another unsubstituted, for the inhibition of the enzyme. Fluorine substitution on the substituted phenyl ring has an important contribution to the activity. R-configurations of the aliphatic chain substituents provide the exact conformation of the molecules to enter into the binding pockets of the receptor(s). [figure: see text]. General structure of benzodiazepine containing gamma-secretase inhibitors.

  6. Synthesis of Tertiary and Quaternary Amine Derivatives from Wood Resin as Chiral NMR Solvating Agents

    Directory of Open Access Journals (Sweden)

    Tiina Laaksonen

    2015-11-01

    Full Text Available Chiral tertiary and quaternary amine solvating agents for NMR spectroscopy were synthesized from the wood resin derivative (+-dehydroabietylamine (2. The resolution of enantiomers of model compounds [Mosher’s acid (3 and its n-Bu4N salt (4] (guests by (+-dehydroabietyl-N,N-dimethylmethanamine (5 and its ten different ammonium salts (hosts was studied. The best results with 3 were obtained using 5 while with 4 the best enantiomeric resolution was obtained using (+-dehydroabietyl-N,N-dimethylmethanaminium bis(trifluoromethane-sulfonimide (6. The compounds 5 and 6 showed a 1:1 complexation behaviour between the host and guest. The capability of 5 and 6 to recognize the enantiomers of various α-substituted carboxylic acids and their n-Bu4N salts in enantiomeric excess (ee determinations was demonstrated. A modification of the RES-TOCSY NMR pulse sequence is described, allowing the enhancement of enantiomeric discrimination when the resolution of multiplets is insufficient.

  7. Synthesis of Some Unique Carbamate Derivatives bearing 2-Furoyl-1-piperazine as a Valuable Therapeutic Agents.

    Science.gov (United States)

    Abbasi, Athar; Hussain, Ghulam; Rehman, Aziz Ur; Siddiqui, Zahra; Shah, Adnan Ali; Lodhi, Arif; Khan, Ali; Ashraf, Muhammad; Ain, Qurat Ul; Ahmad, Irshad; Malik, Rabia; Shahid, Muhammad; Mushtaq, Zahid

    2017-01-01

    The aim of the research work was to synthesize different biologically active carbamate derivatives bearing 2-furoyl-1-piperazine and having modest toxicity. The synthesis was completed as a multiple sequence. The structural confirmation of all the synthesized compounds was obtained by EI-MS, IR and 1H-NMR spectral data. The enzyme inhibition and antibacterial potential of the synthesized compounds was evaluated. To find the utility of the prepared compounds as possible therapeutic agents their cytotoxicity was also checked. All the compounds were active against acetylcholinesterase enzyme, especially 12 and 14 showed very good inhibitory potential relative to Eserine, a reference standard. Almost all the compounds showed good activities against both Gram-positive and Gram-negative bacterial strains.

  8. Chiral trans-1,2-diaminocyclohexane derivatives as chiral solvating agents for carboxylic acids

    Indian Academy of Sciences (India)

    Mariappan Periasamy; Manasi Dalai; Meduri Padmaja

    2010-07-01

    Efficient use of the readily accessible chiral 2-symmetric acyclic diamines (1-2) as well as macrocyclic amines (3-5) containing trans-1,2-diaminocyclohexyl moiety as chiral solvating agents (CSA) for the determination of enantiomeric excess of representative carboxylic acids (6-7) and an amino acid derivative (8) is illustrated. The enantiomeric composition of different carboxylic acids estimated here by the 1H NMR method, based on the integration of the corresponding methine proton signals are in good correlation with that determined using HPLC method. The data are in accordance with the formation of multimolecular diastereomeric complexes in solution, which render good splitting of NMR signals for the enantiomers of representative carboxylic acids as well as for -Ts-phenylglycine (up to = 0.295 ppm, 118 Hz).

  9. A theory of biological relativity: no privileged level of causation.

    Science.gov (United States)

    Noble, Denis

    2012-02-06

    Must higher level biological processes always be derivable from lower level data and mechanisms, as assumed by the idea that an organism is completely defined by its genome? Or are higher level properties necessarily also causes of lower level behaviour, involving actions and interactions both ways? This article uses modelling of the heart, and its experimental basis, to show that downward causation is necessary and that this form of causation can be represented as the influences of initial and boundary conditions on the solutions of the differential equations used to represent the lower level processes. These insights are then generalized. A priori, there is no privileged level of causation. The relations between this form of 'biological relativity' and forms of relativity in physics are discussed. Biological relativity can be seen as an extension of the relativity principle by avoiding the assumption that there is a privileged scale at which biological functions are determined.

  10. Optimization of biguanide derivatives as selective antitumor agents blocking adaptive stress responses in the tumor microenvironment.

    Science.gov (United States)

    Narise, Kosuke; Okuda, Kensuke; Enomoto, Yukihiro; Hirayama, Tasuku; Nagasawa, Hideko

    2014-01-01

    Adaptive cellular responses resulting from multiple microenvironmental stresses, such as hypoxia and nutrient deprivation, are potential novel drug targets for cancer treatment. Accordingly, we focused on developing anticancer agents targeting the tumor microenvironment (TME). In this study, to search for selective antitumor agents blocking adaptive responses in the TME, thirteen new compounds, designed and synthesized on the basis of the arylmethylbiguanide scaffold of phenformin, were used in structure activity relationship studies of inhibition of hypoxia inducible factor (HIF)-1 and unfolded protein response (UPR) activation and of selective cytotoxicity under glucose-deprived stress conditions, using HT29 cells. We conducted luciferase reporter assays using stable cell lines expressing either an HIF-1-responsive reporter gene or a glucose-regulated protein 78 promoter-reporter gene, which were induced by hypoxia and glucose deprivation stress, respectively, to screen for TME-targeting antitumor drugs. The guanidine analog (compound 2), obtained by bioisosteric replacement of the biguanide group, had activities comparable with those of phenformin (compound 1). Introduction of various substituents on the phenyl ring significantly affected the activities. In particular, the o-methylphenyl analog compound 7 and the o-chlorophenyl analog compound 12 showed considerably more potent inhibitory effects on HIF-1 and UPR activation than did phenformin, and excellent selective cytotoxicity under glucose deprivation. These compounds, therefore, represent an improvement over phenformin. They also suppressed HIF-1- and UPR-related protein expression and secretion of vascular endothelial growth factor-A. Moreover, these compounds exhibited significant antiangiogenic effects in the chick chorioallantoic membrane assay. Our structural development studies of biguanide derivatives provided promising candidates for a novel anticancer agent targeting the TME for selective cancer

  11. Preventative and Curative Effects of Several Plant Derived Agents Against Powdery Mildew Disease of Okra

    Directory of Open Access Journals (Sweden)

    Moustafa Hemdan Ahmed MOHARAM

    2012-08-01

    Full Text Available The preventative and curative effects of some plant derived agents based on plant extracts or essential oils were studied at different concentrations against Erysiphe cichoracearum DC. ex Merat, the causal pathogen of okra powdery mildew by the detached leaf-disk and potted plants bioassays. Through detached leaf-disk assay, the highest mean preventative effect (97.74% was recorded by neem seed oil followed by jojoba oil (89.82% and extract of Rynoutria sachalinensis (82.77%. Neem seed oil at 1% was the most effective agent followed by jojoba oil and extract of R. sachalinensis at 1.5% and 2%, respectively, where they suppressed E. cichoracearum completely. Potted plants assay revealed that neem seed oil, jojoba oil and extract of R. sachalinensis as well as the fungicide (active ingredient dinocap showed higher preventative efficacy at all leaf olds treated after 7 and 14 days of inoculation as compared with extracts of henna and garlic. Moreover, the preventative efficacy partly remained apparent after 14 days of inoculation at all leaf olds tested. In field trials through 2010 and 2011 growing seasons, when the first symptoms of powdery mildew appeared naturally, 1.5% jojoba oil, 2% extract of R. sachalinensis and 1% neem seed oil were sprayed individually twice on grown plants to evaluate their efficacy on controlling powdery mildew, growth and yield of okra. Resulted showed that neem seed oil was the most effective agent and highly decreased the disease severity to 29.92%, recorded the highly curative effect (68.15% and also improved plant growth and pods yield.

  12. Diametral tensile strength and film thickness of an experimental dental luting agent derived from castor oil

    Directory of Open Access Journals (Sweden)

    Juliana Cabrini Carmello

    2012-02-01

    Full Text Available The need to develop new dental luting agents in order to improve the success of treatments has greatly motivated research. OBJECTIVE: The aim of this study was to evaluate the diametral tensile strength (DTS and film thickness (FT of an experimental dental luting agent derived from castor oil (COP with or without addition of different quantities of filler (calcium carbonate - CaCO3. MATERIAL AND METHODS: Eighty specimens were manufactured (DTS N=40; FT N=40 and divided into 4 groups: Pure COP; COP 10%; COP 50% and zinc phosphate (control. The cements were mixed according to the manufacturers' recommendations and submitted to the tests. The DTS test was performed in the MTS 810 testing machine (10 KN, 0.5 mm/min. For FT test, the cements were sandwiched between two glass plates (2 cm² and a load of 15 kg was applied vertically on the top of the specimen for 10 min. The data were analyzed by means of one-way ANOVA and Tukey's test (α=0.05. RESULTS: The values of DTS (MPa were: Pure COP- 10.94±1.30; COP 10%- 30.06±0.64; COP 50%- 29.87±0.27; zinc phosphate- 4.88±0.96. The values of FT (µm were: Pure COP- 31.09±3.16; COP 10%- 17.05±4.83; COP 50%- 13.03±4.83; Zinc Phosphate- 20.00±0.12. One-way ANOVA showed statistically significant differences among the groups (DTS - p=1.01E-40; FT - p=2.4E-10. CONCLUSION: The experimental dental luting agent with 50% of filler showed the best diametral tensile strength and film thickness.

  13. Synthesis and tissue distribution of substituted [{sup 125}I]iodophenylamine derivatives: Possible brain imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Ghaffari, M.A.; Ali, H.; Rousseau, J.; Lier, J.E. van

    1997-02-01

    The synthesis and brain uptake in mice of the radioidinated derivatives of N,N-dimethyl-N'-(idodimethoxyphenyl)-1,3-propanediamine, as well as the N-substituted derivatives of (iodoalkylphenyl)isopropyl, iodoalkylphenylethylamine and 3,4-(methylenedioxy)phenyl-amphetamine (MDA) are described. These compounds contain structural features of both IMP and HIPDM, the cerebral perfusion agents currently in clinical use. The radiolabeled analogs were obtained via the [{sup 125}I]I exchange method, or by [{sup 125}I]NaI treatment of the iodo-free precursor in the presence of an oxidant. Following intravenous injection in mice, all compounds showed important radioactivity concentrations in the lungs and kidneys. The N-substituted (iodoalkylphenyl)isopropyl and iodoalkylphenyl-ethylamine derivatives displayed a high initial brain uptake (>10%IDg{sup -1}) followed by a rapid clearance phase, resulting in lower brain-to-blood ratios as those reported for IMP and HIPDM. In contrast, N,N-dimethyl-N'-(iododimethoxyphenyl)-1,3-propanediamine derivatives featuring the iodo substituent on the benzene carbon adjacent to the methyl amine group and the methoxy substituents on the 2,5- or 2,4-positions, showed low but more persistant brain uptake. Combined with fast blood clearance, this resulted in high brain-to-blood ratios at later time points. Among all compounds tested, the highest brain-to-blood ratio was observed with compound N,N-dimethyl-N'-(6-iodo-3,4-dimethoxyphenyl)-1,3-propanediamine (27e), reaching a maximum of >20 at 12 h post-injection.

  14. Design, Synthesis, Molecular Docking, and Antibacterial Evaluation of Some Novel Flouroquinolone Derivatives as Potent Antibacterial Agent

    Directory of Open Access Journals (Sweden)

    Mehul M. Patel

    2014-01-01

    Full Text Available Objective. Quinolone moiety is an important class of nitrogen containing heterocycles widely used as key building blocks for medicinal agents. It exhibits a wide spectrum of pharmacophores and has bactericidal, antiviral, antimalarial, and anticancer activities. In view of the reported antimicrobial activity of various fluoroquinolones, the importance of the C-7 substituents is that they exhibit potent antimicrobial activities. Our objective was to synthesize newer quinolone analogues with increasing bulk at C-7 position of the main 6-fluoroquinolone scaffold to produce the target compounds which have potent antimicrobial activity. Methods. A novel series of 1-ethyl-6-fluoro-4-oxo-7-{4-[2-(4-substituted phenyl-2-(substituted-ethyl]-1-piperazinyl}-1,4-dihydroquinoline-3-carboxylic acid derivatives were synthesized. To understand the interaction of binding sites with bacterial protein receptor, the docking study was performed using topoisomerase II DNA gyrase enzymes (PDB ID: 2XCT by Schrodinger’s Maestro program. In vitro antibacterial activity of the synthesized compounds was studied and the MIC value was calculated by the broth dilution method. Results. Among all the synthesized compounds, some compounds showed potent antimicrobial activity. The compound 8g exhibited good antibacterial activity. Conclusion. This investigation identified the potent antibacterial agents against certain infections.

  15. Synthesis and biological evaluation of oxindole linked indolyl-pyrimidine derivatives as potential cytotoxic agents.

    Science.gov (United States)

    Prajapti, Santosh Kumar; Nagarsenkar, Atulya; Guggilapu, Sravanthi Devi; Gupta, Keshav Kumar; Allakonda, Lingesh; Jeengar, Manish Kumar; Naidu, V G M; Babu, Bathini Nagendra

    2016-07-01

    In our endeavor towards the development of effective cytotoxic agents, a series of oxindole linked indolyl-pyrimidine derivatives were synthesized and characterized by IR, (1)H NMR, (13)C NMR and Mass spectral analysis. All the newly synthesized target compounds were assessed against PA-1 (ovarian), U-87MG (glioblastoma), LnCaP (prostate), and MCF-7 (Breast) cancer cell lines for their cytotoxic potential, with majority of them showing inhibitory activity at low micro-molar concentrations. Significantly, compound 8e was found to be most potent amongst all the tested compounds with an IC50 value of (2.43±0.29μM) on PA-1 cells. The influence of the most active cytotoxic compound 8e on the cell cycle distribution was assessed on the PA-1 cell line, exhibiting a cell cycle arrest at the G2/M phase. Moreover, acridine orange/ethidium bromide staining and annexin V binding assay confirmed that compound 8e can induce cell apoptosis in PA-1 cells. These preliminary results persuade further investigation on the synthesized compounds aiming to the development of potential cytotoxic agents.

  16. Synthesis and Evaluation of New Benzodioxole- Based Thiosemicarbazone Derivatives as Potential Antitumor Agents

    Directory of Open Access Journals (Sweden)

    Mehlika Dilek Altıntop

    2016-11-01

    Full Text Available New benzodioxole-based thiosemicarbazone derivatives were synthesized and evaluated for their cytotoxic effects on A549 human lung adenocarcinoma, C6 rat glioma and NIH/3T3 mouse embryonic fibroblast cells. In order to examine the correlation between anticancer activity and cholinesterases, the compounds were evaluated for their inhibitory effects on AChE and BuChE. The most effective anticancer agents were investigated for their effects on DNA synthesis, apoptosis and mitochondrial membrane potential. 4-(1,3-Benzodioxol-5-yl-1-([1,1′-biphenyl]-4-ylmethylenethiosemicarbazide (5 was identified as the most promising anticancer agent against C6 and A549 cell lines due to its inhibitory effects on C6 and A549 cells and low toxicity to NIH/3T3 cells. Compound 5 increased early and late apoptosis in A549 and C6 cells. Compound 5 also caused disturbance on mitochondrial membrane potential and showed DNA synthesis inhibitory activity in A549 and C6 cells. Compound 5 was investigated for SIRT1 inhibitory activity to provide mechanistic insight and for that purpose docking studies were also performed for this compound on SIRT1. On the other hand, compound 5 did not show any inhibitory activity against AChE and BuChE. This outcome pointed out that there is no relationship between anticancer activity of compound 5 and cholinesterases.

  17. Synthesis and Evaluation of Ester Derivatives of 10-Hydroxycanthin-6-one as Potential Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Fei Zhao

    2016-03-01

    Full Text Available As part of our continuing research on canthin-6-one antimicrobial agents, a new series of ester derivatives of 10-hydroxycanthin-6-one were synthesized using a simple and effective synthetic route. The structure of each compound was characterized by NMR, ESI-MS, FT-IR, UV, and elemental analysis. The antimicrobial activity of these compounds against three phytopathogenic fungi (Alternaria solani, Fusarium graminearum, and Fusarium solani and four bacteria (Bacillus cereus, Bacillus subtilis, Ralstonia solanacearum, and Pseudomonas syringae were evaluated using the mycelium linear growth rate method and micro-broth dilution method, respectively. The structure-activity relationship is discussed. Of the tested compounds, 4 and 7s displayed significant antifungal activity against F. graminearum, with inhibition rates of 100% at a concentration of 50 μg/mL. Compounds 5, 7s, and 7t showed the best inhibitory activity against all the tested bacteria, with minimum inhibitory concentrations (MICs between 3.91 and 31.25 μg/mL. Thus, 7s emerged as a promising lead compound for the development of novel canthine-6-one antimicrobial agents.

  18. Synthesis and Evaluation of Ester Derivatives of 10-Hydroxycanthin-6-one as Potential Antimicrobial Agents.

    Science.gov (United States)

    Zhao, Fei; Dai, Jiang-Kun; Liu, Dan; Wang, Shi-Jun; Wang, Jun-Ru

    2016-03-21

    As part of our continuing research on canthin-6-one antimicrobial agents, a new series of ester derivatives of 10-hydroxycanthin-6-one were synthesized using a simple and effective synthetic route. The structure of each compound was characterized by NMR, ESI-MS, FT-IR, UV, and elemental analysis. The antimicrobial activity of these compounds against three phytopathogenic fungi (Alternaria solani, Fusarium graminearum, and Fusarium solani) and four bacteria (Bacillus cereus, Bacillus subtilis, Ralstonia solanacearum, and Pseudomonas syringae) were evaluated using the mycelium linear growth rate method and micro-broth dilution method, respectively. The structure-activity relationship is discussed. Of the tested compounds, 4 and 7s displayed significant antifungal activity against F. graminearum, with inhibition rates of 100% at a concentration of 50 μg/mL. Compounds 5, 7s, and 7t showed the best inhibitory activity against all the tested bacteria, with minimum inhibitory concentrations (MICs) between 3.91 and 31.25 μg/mL. Thus, 7s emerged as a promising lead compound for the development of novel canthine-6-one antimicrobial agents.

  19. Plants-Derived Neuroprotective Agents: Cutting the Cycle of Cell Death through Multiple Mechanisms

    Directory of Open Access Journals (Sweden)

    Taiwo Olayemi Elufioye

    2017-01-01

    Full Text Available Neuroprotection is the preservation of the structure and function of neurons from insults arising from cellular injuries induced by a variety of agents or neurodegenerative diseases (NDs. The various NDs including Alzheimer’s, Parkinson’s, and Huntington’s diseases as well as amyotropic lateral sclerosis affect millions of people around the world with the main risk factor being advancing age. Each of these diseases affects specific neurons and/or regions in the brain and involves characteristic pathological and molecular features. Hence, several in vitro and in vivo study models specific to each disease have been employed to study NDs with the aim of understanding their underlying mechanisms and identifying new therapeutic strategies. Of the most prevalent drug development efforts employed in the past few decades, mechanisms implicated in the accumulation of protein-based deposits, oxidative stress, neuroinflammation, and certain neurotransmitter deficits such as acetylcholine and dopamine have been scrutinized in great detail. In this review, we presented classical examples of plant-derived neuroprotective agents by highlighting their structural class and specific mechanisms of action. Many of these natural products that have shown therapeutic efficacies appear to be working through the above-mentioned key multiple mechanisms of action.

  20. Recent progress in the drug development of coumarin derivatives as potent antituberculosis agents.

    Science.gov (United States)

    Keri, Rangappa S; Sasidhar, B S; Nagaraja, Bhari Mallanna; Santos, M Amélia

    2015-07-15

    Tuberculosis (TB) is still a challenging worldwide health problem and mycobacterium tuberculosis (MTB) remains one of the most deadly human pathogens. TB is the second leading infectious cause of mortality today behind only HIV/AIDS. The impetus for developing new structural classes of antituberculosis drugs comes from the emergence of multi-drug resistant (MDR) strains. The development of MDR strains to commonly used drugs is due to, longer durations of therapy as results of resistance, and the resurgence of the disease in immune compromised patients. Therefore, there is an urgent need to explore new antitubercular (anti-TB) agents. Ironically, the low number of potentially new chemical entities which can act as anti-TB candidates is of great importance at present situation. Considering the severity of the problem, WHO has prepared a strategic plan in Berlin declaration 2007 to stop TB, globally. Among the oxygen heterocycles, coumarin derivatives are important motifs, which can be widely found in many natural products, and many of them displaying diverse biological activities. This spectacular spectrum of applications has intrigued organic and medicinal chemists for decades to explore the natural coumarins or their synthetic analogs for their applicability as anti-TB drugs. To pave the way for the future research, there is a need to collect the latest information in this promising area. In the present review, we collated published reports on coumarin derivatives to shed light on the insights on different types of methods reported for their preparations, characterizations and anti-TB applications, so that its full therapeutic potential class of compounds can be utilized for the treatment of tuberculosis. Therefore, the objective of this review is to focus on important coumarin analogs with anti-TB activities, and structure-activity relationships (SAR) for designing the better anti-TB agents. It is hoped that, this review will be helpful for new thoughts in the

  1. Synthesis and Evaluation of Aminothiazole-Paeonol Derivatives as Potential Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Chia-Ying Tsai

    2016-01-01

    Full Text Available In this study, novel aminothiazole-paeonol derivatives were synthesized and characterized using 1H-NMR, 13C-NMR, IR, mass spectroscopy, and high performance liquid chromatography. All the new synthesized compounds were evaluated according to their anticancer effect on seven cancer cell lines. The experimental results indicated that these compounds possess high anticancer potential regarding human gastric adenocarcinoma (AGS cells and human colorectal adenocarcinoma (HT-29 cells. Among these compounds, N-[4-(2-hydroxy-4-methoxyphenylthiazol-2-yl]-4-methoxybenzenesulfonamide (13c had the most potent inhibitory activity, with IC50 values of 4.0 µM to AGS, 4.4 µM to HT-29 cells and 5.8 µM to HeLa cells. The 4-fluoro-N-[4-(2-hydroxy-4-methoxyphenylthiazol-2-yl]benzenesulfonamide (13d was the second potent compound, showing IC50 values of 7.2, 11.2 and 13.8 µM to AGS , HT-29 and HeLa cells, respectively. These compounds are superior to 5-fluorouracil (5-FU for relatively higher potency against AGS and HT-29 human cancer cell lines along with lower cytotoxicity to fibroblasts. Novel aminothiazole-paeonol derivatives in this work might be a series of promising lead compounds to develop anticancer agents for treating gastrointestinal adenocarcinoma.

  2. Marinopyrrole Derivatives as Potential Antibiotic Agents against Methicillin-Resistant Staphylococcus aureus (II

    Directory of Open Access Journals (Sweden)

    Rongshi Li

    2013-08-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA continues to be a major problem, causing severe and intractable infections worldwide. MRSA is resistant to all beta-lactam antibiotics, and alternative treatments are limited. A very limited number of new antibiotics have been discovered over the last half-century, novel agents for the treatment of MRSA infections are urgently needed. Marinopyrrole A was reported to show antibiotic activity against MRSA in 2008. After we reported the first total synthesis of (±-marinopyrrole A, we designed and synthesized a series of marinopyrrole derivatives. Our structure activity relationship (SAR studies of these novel derivatives against a panel of Gram-positive pathogens in antibacterial assays have revealed that a para-trifluoromethyl analog (33 of marinopyrrole A is ≥63-, 8-, and 4-fold more potent than vancomycin against methicillin-resistant Staphylococcus epidermidis (MRSE, methicillin-susceptible Staphylococcus aureus (MSSA and MRSA, respectively. The results provide valuable information in the search for new-generation antibiotics.

  3. Understanding the mode of action of a pterostilbene derivative as anti-inflammatory agent.

    Science.gov (United States)

    Nikhil, Kumar; Sharan, Shruti; Palla, Srinivasa Rao; Sondhi, Sham M; Peddinti, Rama Krishna; Roy, Partha

    2015-09-01

    Inflammatory response plays an important role not only in the normal physiology, but also in the pathology of certain diseases such as cancers. In our previous study, we found a novel derivative of pterostilbene (PTER), to be an effective inducer of apoptosis in human breast and prostate cancer cells affecting various cellular targets. Herein, we further attempted to investigate its anti-inflammatory potential followed by its probable mode of action. The newly developed compound was tested for its anti-inflammatory actions in lipopolysaccharide (LPS) stimulated RAW264.7 macrophages and carrageenan induced rat paw edema models. Our data showed that the derivative inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) as well as the downstream products like nitric oxide (NO) and PGE2, at much lower doses as compared to PTER. This effect was found to be associated with the inhibition of phosphorylation/degradation of IκB-α and nuclear translocation of the p-NFκB p65. Moreover, inhibition of mitogen-activated protein kinases (MAPKs) and activator protein-1 (AP-1) was also observed. In addition, the newly developed compound also reduced the paw edema, the tissue content of NO, PGE2 and expression of iNOS and COX-2 proteins within the tissues after λ-carrageenan stimulation. Taken together, our findings provide the possibility that the PTER derivative might have enhanced cancer chemopreventive potential based on its stronger anti-NFκB and anti-inflammatory activities as compared to its natural counterpart, i.e., PTER. Thus, this compound can be used towards the development of an effective anti-inflammatory agent.

  4. Plant-derived anticancer agents: a promising treatment for bone metastasis

    Science.gov (United States)

    Juárez, Patricia

    2014-01-01

    Bone metastasis is a very frequent complication of advanced cancer, and it remains an incurable disease. Current therapies that have been approved for the treatment of bone metastases delay the occurrence of skeletal-related events and can extend the patient's lifespan by a few years. However, they will not cure or cause the regression of established bone metastases, and new side effects are emerging after prolonged treatment. Thus, new therapies are severely needed. There are compelling evidences from in vitro and in vivo preclinical studies that support the use of compounds derived from plants to treat several forms of cancers including bone metastasis. More than 25% of the drugs used during the past 20 years were directly derived from plants, whereas another 25% are chemically altered natural products. Still, only 5–15% of the ∼250 000 higher plants have ever been investigated for bioactive compounds. There is a growing interest for the study of anticancer drugs with relatively low side effects that target specific key signaling pathways that control the establishment and progression of the cancer metastasis. Therefore, further studies are needed to identify new natural compounds with high efficiency in cancer prevention and treatment. Extensive reviews about plant-derived agents and their use in cancer have been published, but none when it comes to the treatment of bone metastases. Only a few of these compounds have been evaluated for the treatment of bone metastasis; here we describe some of the most prominent ones that are having the potential to reach the clinic soon.

  5. Rational design of biaryl pharmacophore inserted noscapine derivatives as potent tubulin binding anticancer agents

    Science.gov (United States)

    Santoshi, Seneha; Manchukonda, Naresh Kumar; Suri, Charu; Sharma, Manya; Sridhar, Balasubramanian; Joseph, Silja; Lopus, Manu; Kantevari, Srinivas; Baitharu, Iswar; Naik, Pradeep Kumar

    2015-03-01

    We have strategically designed a series of noscapine derivatives by inserting biaryl pharmacophore (a major structural constituent of many of the microtubule-targeting natural anticancer compounds) onto the scaffold structure of noscapine. Molecular interaction of these derivatives with α,β-tubulin heterodimer was investigated by molecular docking, molecular dynamics simulation, and binding free energy calculation. The predictive binding affinity indicates that the newly designed noscapinoids bind to tubulin with a greater affinity. The predictive binding free energy (ΔGbind, pred) of these derivatives (ranging from -5.568 to -5.970 kcal/mol) based on linear interaction energy (LIE) method with a surface generalized Born (SGB) continuum solvation model showed improved binding affinity with tubulin compared to the lead compound, natural α-noscapine (-5.505 kcal/mol). Guided by the computational findings, these new biaryl type α-noscapine congeners were synthesized from 9-bromo-α-noscapine using optimized Suzuki reaction conditions for further experimental evaluation. The derivatives showed improved inhibition of the proliferation of human breast cancer cells (MCF-7), human cervical cancer cells (HeLa) and human lung adenocarcinoma cells (A549), compared to natural noscapine. The cell cycle analysis in MCF-7 further revealed that these compounds alter the cell cycle profile and cause mitotic arrest at G2/M phase more strongly than noscapine. Tubulin binding assay revealed higher binding affinity to tubulin, as suggested by dissociation constant (Kd) of 126 ± 5.0 µM for 5a, 107 ± 5.0 µM for 5c, 70 ± 4.0 µM for 5d, and 68 ± 6.0 µM for 5e compared to noscapine (Kd of 152 ± 1.0 µM). In fact, the experimentally determined value of ΔGbind, expt (calculated from the Kd value) are consistent with the predicted value of ΔGbind, pred calculated based on LIE-SGB. Based on these results, one of the derivative 5e of this series was used for further toxicological

  6. Discovery and Development of Natural Product-derived Chemotherapeutic Agents Based on a Medicinal Chemistry Approach⊥†

    OpenAIRE

    Lee, Kuo-Hsiung

    2010-01-01

    Medicinal plants have long been an excellent source of pharmaceutical agents. Accordingly, the long term objectives of the author's research program are to discover and design new chemotherapeutic agents based on plant-derived compound leads by using a medicinal chemistry approach, which is a combination of chemistry and biology. Different examples of promising bioactive natural products and their synthetic analogs, including sesquiterpene lactones, quassinoids, naphthoquinones, phenylquinolo...

  7. Discovery and Development of Natural Product-derived Chemotherapeutic Agents Based on a Medicinal Chemistry Approach⊥†

    OpenAIRE

    Lee, Kuo-Hsiung

    2010-01-01

    Medicinal plants have long been an excellent source of pharmaceutical agents. Accordingly, the long term objectives of the author's research program are to discover and design new chemotherapeutic agents based on plant-derived compound leads by using a medicinal chemistry approach, which is a combination of chemistry and biology. Different examples of promising bioactive natural products and their synthetic analogs, including sesquiterpene lactones, quassinoids, naphthoquinones, phenylquinolo...

  8. Synthetic 2-aroylindole derivatives as a new class of potent tubulin-inhibitory, antimitotic agents.

    Science.gov (United States)

    Mahboobi, S; Pongratz, H; Hufsky, H; Hockemeyer, J; Frieser, M; Lyssenko, A; Paper, D H; Bürgermeister, J; Böhmer, F D; Fiebig, H H; Burger, A M; Baasner, S; Beckers, T

    2001-12-20

    A new class of simple synthetic antimitotic compounds based on 2-aroylindoles was discovered. (5-Methoxy-1H-2-indolyl)-phenylmethanone (1) as well as analogous 3-fluorophenyl- (36) and 3-methoxyphenyl (3) derivatives displayed high cytotoxicity of IC(50) = 20 to 75 nM against the human HeLa/KB cervical, SK-OV-3 ovarian, and U373 astrocytoma carcinoma cell lines. The inhibition of proliferation correlated with the arrest in the G2/M phase of the cell cycle. In in vitro assays with tubulin isolated from bovine brain, in general antiproliferative activity correlated with inhibition of tubulin polymerization. Thus, the antimitotic activity of 2-aroylindoles is explained by interference with the mitotic spindle apparatus and destabilization of microtubules. In contrast to colchicine, vincristine, nocodazole, or taxol, 1 did not significantly affect the GTPase activity of beta-tubulin. Interestingly, selected compounds inhibited angiogenesis in the chorioallantoic membrane (CAM) assay. In xenograft experiments, 1 was highly active after oral administration at 200 mg/kg against the human amelanocytic melanoma MEXF 989 in athymic nude mice. We conclude, that 2-aroylindoles constitute an interesting new class of antitubulin agents with the potential to be clinically developed for cancer treatment.

  9. Synthesis and Biological Evaluation of 2-Aminobenzamide Derivatives as Antimicrobial Agents: Opening/Closing Pharmacophore Site

    Directory of Open Access Journals (Sweden)

    Yahia N. Mabkhot

    2014-03-01

    Full Text Available A series of new 2-aminobenzamide derivatives (1–10 has been synthesized in good to excellent yields by adopting both conventional and/or a time-efficient microwave assisted methodologies starting from isatoic anhydride (ISA and characterized on the basis of their physical, spectral and microanalytical data. Selected compounds of this series were then tested against various bacterial (Bacillus subtilis (RCMB 000107 and Staphylococcus aureus (RCMB 000106. Pseudomonas aeruginosa (RCMB 000102 and Escherichia coli (RCMB 000103 and fungal strains (Saccharomyces cerevisiae (RCMB 006002, Aspergillus fumigatus (RCMB 002003 and Candida albicans (RCMB 005002 to explore their potential as antimicrobial agents. Compound 5 was found to be the most active compound among those tested, which showed excellent antifungal activity against Aspergillus fumigatus (RCMB 002003 more potent than standard Clotrimazole, and moderate to good antibacterial and antifungal activity against most of the other strains of bacteria and fungi. Furthermore, potential pharmacophore sites were identified and their activity was related with the structures in the solution.

  10. Synthesis and Biological Evaluation of Novel 2-Methoxypyridylamino-Substituted Riminophenazine Derivatives as Antituberculosis Agents

    Directory of Open Access Journals (Sweden)

    Dongfeng Zhang

    2014-04-01

    Full Text Available Clofazimine, a member of the riminophenazine class, is one of the few antibiotics that are still active against multidrug-resistant Mycobacterium tuberculosis (M. tuberculosis. However, the clinical utility of this agent is limited by its undesirable physicochemical properties and skin pigmentation potential. With the goal of maintaining potent antituberculosis activity while improving physicochemical properties and lowering skin pigmentation potential, a series of novel riminophenazine derivatives containing a 2-methoxypyridylamino substituent at the C-2 position of the phenazine nucleus were designed and synthesized. These compounds were evaluated for antituberculosis activity against M. tuberculosis H37Rv and screened for cytotoxicity. Riminophenazines bearing a 3-halogen- or 3,4-dihalogen-substituted phenyl group at the N-5 position exhibited potent antituberculosis activity, with MICs ranging from 0.25~0.01 μg/mL. The 3,4-dihalogen- substituted compounds displayed low cytotoxicity, with IC50 values greater than 64 μg/mL. Among these riminophenazines, compound 15 exhibited equivalent in vivo efficacy against M. tuberculosis infection and reduced skin discoloration potential in an experimental mouse infection model as compared to clofazimine. Compound 15, as compared to clofazimine, also demonstrated improved physicochemical properties and pharmacokinetic profiles with a short half-life and less drug tissue accumulation. This compound is being evaluated as a potential drug candidate for the treatment of multidrug resistant tuberculosis.

  11. Statin derivatives as therapeutic agents for castration-resistant prostate cancer.

    Science.gov (United States)

    Ingersoll, Matthew A; Miller, Dannah R; Martinez, October; Wakefield, C Brent; Hsieh, Kuan-Chan; Simha, M Vijaya; Kao, Chai-Lin; Chen, Hui-Ting; Batra, Surinder K; Lin, Ming-Fong

    2016-12-01

    Despite recent advances in modern medicine, castration-resistant prostate cancer remains an incurable disease. Subpopulations of prostate cancer cells develop castration-resistance by obtaining the complete steroidogenic ability to synthesize androgens from cholesterol. Statin derivatives, such as simvastatin, inhibit cholesterol biosynthesis and may reduce prostate cancer incidence as well as progression to advanced, metastatic phenotype. In this study, we demonstrate novel simvastatin-related molecules SVA, AM1, and AM2 suppress the tumorigenicity of prostate cancer cell lines including androgen receptor-positive LNCaP C-81 and VCaP as well as androgen receptor-negative PC-3 and DU145. This is achieved through inhibition of cell proliferation, colony formation, and migration as well as induction of S-phase cell-cycle arrest and apoptosis. While the compounds effectively block androgen receptor signaling, their mechanism of inhibition also includes suppression of the AKT pathway, in part, through disruption of the plasma membrane. SVA also possess an added effect on cell growth inhibition when combined with docetaxel. In summary, of the compounds studied, SVA is the most potent inhibitor of prostate cancer cell tumorigenicity, demonstrating its potential as a promising therapeutic agent for castration-resistant prostate cancer.

  12. Synthesis and bioactivity of novel triazole incorporated benzothiazinone derivatives as antitubercular and antioxidant agent.

    Science.gov (United States)

    Shaikh, Mubarak H; Subhedar, Dnyaneshwar D; Arkile, Manisha; Khedkar, Vijay M; Jadhav, Nandadeep; Sarkar, Dhiman; Shingate, Bapurao B

    2016-01-15

    In search of new active molecules against Mycobacterium tuberculosis (MTB) H37Ra and M. bovis BCG, a small focused library of benzothiazinone based 1,2,3-triazoles has been efficiently prepared via click chemistry approach. Several derivatives were found to be promising inhibitors of MTB and M. bovis BCG characterized by lower MIC values (27.34-29.37μg/mL). Among all the synthesized compounds, 6c and 6e is the most active compound against MTB and M. bovis BCG. The compounds were further tested for anti-proliferative activity against HeLa, A549 and A431 cell lines using MTT assay and showed no significant cytotoxic activity at the maximum concentration evaluated. Further, the synthesized compounds were found to have potential antioxidant activity with IC50 range=14.14-47.11μg/mL. Furthermore, to rationalize the observed biological activity data, the molecular docking study also been carried out against a potential target MTB DprE1, which revealed a significant correlation between the binding score and biological activity for these compounds. The results of the in vitro and in silico study suggest that the triazole incorporated benzothiazinone may possess the ideal structural requirements for further development of novel therapeutic agents.

  13. Synthesis of dihydropyrazole sulphonamide derivatives that act as anti-cancer agents through COX-2 inhibition.

    Science.gov (United States)

    Qiu, Han-Yue; Wang, Peng-Fei; Li, Zhen; Ma, Jun-Ting; Wang, Xiao-Ming; Yang, Yong-Hua; Zhu, Hai-Liang

    2016-02-01

    COX-2 has long been exploited in the treatment of inflammation and relief of pain; however, research increasingly suggests COX-2 inhibitors might possess potential benefits to thwart tumour processes. In the present study, we designed a series of novel COX-2 inhibitors based on analysis of known inhibitors combined with an in silico scaffold modification strategy. A docking simulation combined with a primary screen in vitro were performed to filter for the lead compound, which was then substituted, synthesized and evaluated by a variety of bioassays. Derivative 4d was identified as a potent COX-2 enzyme inhibitor and exerted an anticancer effect through COX-2 inhibition. Further investigation confirmed that 4d could induce A549 cell apoptosis and arrest the cell cycle at the G2/M phase. Moreover, treatment with 4d reduced A549 cell adhesive ability and COX-2 expression. The morphological variation of treated cells was also visualized by confocal microscopy. Overall, the biological profile of 4d suggests that this compound may be developed as a potential anticancer agent.

  14. Synthesis and Biological Evaluation of New Ligustrazine Derivatives as Anti-Tumor Agents

    Directory of Open Access Journals (Sweden)

    Haimin Lei

    2012-04-01

    Full Text Available To discover new anti-cancer agents with multi-effect and low toxicity, a series of ligustrazine derivatives were synthesized using several effective anti-tumor ingredients of Shiquandabu Wan as starting materials. Our idea was enlightened by the “combination principle” in drug discovery. The ligustrazine derivatives’ anti-tumor activities were evaluated on the HCT-8, Bel-7402, BGC-823, A-549 and A2780 human cancer cell lines. In addition the angiogenesis activities were valued by the chick chorioallantoic membrane (CAM assay. 1,7-bis(4-(3,5,6-Trimethylpyrazin-2-yl-3-methoxyphenyl-1,6-heptadiene-3,5-dione (4 and 3 α,12 α-dihydroxy-5β-dholanic acid-3,5,6-trimethylpyrazin-2-methyl ester (5 not only displayed antiproliferative activities on these cancer cells, but also dramatically suppressed normal angiogenesis in CAM. The LD50 value of the compound 5 exceeded 3.0 g/kg by oral administration in mice.

  15. Evaluation of Chemical Warfare Agent Percutaneous Vapor Toxicity: Derivation of Toxicity Guidelines for Assessing Chemical Protective Ensembles.

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.

    2003-07-24

    Percutaneous vapor toxicity guidelines are provided for assessment and selection of chemical protective ensembles (CPEs) to be used by civilian and military first responders operating in a chemical warfare agent vapor environment. The agents evaluated include the G-series and VX nerve agents, the vesicant sulfur mustard (agent HD) and, to a lesser extent, the vesicant Lewisite (agent L). The focus of this evaluation is percutaneous vapor permeation of CPEs and the resulting skin absorption, as inhalation and ocular exposures are assumed to be largely eliminated through use of SCBA and full-face protective masks. Selection of appropriately protective CPE designs and materials incorporates a variety of test parameters to ensure operability, practicality, and adequacy. One aspect of adequacy assessment should be based on systems tests, which focus on effective protection of the most vulnerable body regions (e.g., the groin area), as identified in this analysis. The toxicity range of agent-specific cumulative exposures (Cts) derived in this analysis can be used as decision guidelines for CPE acceptance, in conjunction with weighting consideration towards more susceptible body regions. This toxicity range is bounded by the percutaneous vapor estimated minimal effect (EME{sub pv}) Ct (as the lower end) and the 1% population threshold effect (ECt{sub 01}) estimate. Assumptions of exposure duration used in CPE certification should consider that each agent-specific percutaneous vapor cumulative exposure Ct for a given endpoint is a constant for exposure durations between 30 min and 2 hours.

  16. Development of a New Folate-Derived Ga-68-Based PET Imaging Agent.

    Science.gov (United States)

    Brand, Christian; Longo, Valerie A; Groaning, Mike; Weber, Wolfgang A; Reiner, Thomas

    2017-02-13

    The folate receptor (FR) has emerged as an interesting diagnostic and therapeutic drug target with many potential applications in oncologic and inflammatory disorders. It was therefore the aim of this study to develop a folate-derived Ga-68-based positron emission tomography (PET) imaging tracer that is straightforward to radiolabel and could be broadly used in clinical studies. We validated its target binding affinity and specificity and compared it to [(99m)Tc]EC20, the folate single-photon emission computed tomography (SPECT) imaging tracer that has been most extensively studied clinically so far. The new folic acid-derived PET imaging agent is linked via a polyethyleneglycol linker to the chelator 1,4,7-triazacyclononane-1,4,7-trisacetic acid (NOTA). This new compound, NOTA-folate, was labeled with gallium-68. We tested the probe's stability in human plasma and its selectivity in vitro, using the FR-positive KB cell line as well as the FR-negative A549 cell line. The pharmacokinetic profile of [(68)Ga]NOTA-folate was evaluated in FR-positive KB mouse xenografts. Following intravenous injection of [(68)Ga]NOTA-folate (383 ± 53 μCi), PET/computed tomography (CT) imaging studies as well as biodistribution studies were performed using KB tumor-bearing mice (n = 3). In vitro as well as in vivo studies were performed in parallel with the SPECT imaging tracer [(99m)Tc]EC20. In comparison to [(99m)Tc]EC20 (radiochemical yield (RCY) = 82.0 ± 2.9 %, 91.8 ± 2.0 % purity), similar radiochemical yield (87.2 ± 6.9 %) and radiochemical purity (95.6 ± 1.8 %) could be achieved for [(68)Ga]NOTA-folate. For both tracers, we observed high affinity for FR-positive cells in vitro and high plasma stability. In PET/CT and biodistribution studies, [(68)Ga]NOTA-folate appeared to display slightly superior in vivo performance in comparison to [(99m)Tc]EC20. In detail, (68)Ga-NOTA-folate showed very good tumor uptake and retention (6.6 ± 1.1 %ID/g), relatively

  17. Avarol derivatives as competitive AChE inhibitors, non hepatotoxic and neuroprotective agents for Alzheimer's disease.

    Science.gov (United States)

    Tommonaro, Giuseppina; García-Font, Nuria; Vitale, Rosa Maria; Pejin, Boris; Iodice, Carmine; Cañadas, Sixta; Marco-Contelles, José; Oset-Gasque, María Jesús

    2016-10-21

    Avarol is a marine sesquiterpenoid hydroquinone, previously isolated from the marine sponge Dysidea avara Schmidt (Dictyoceratida), with antiinflammatory, antitumor, antioxidant, antiplatelet, anti-HIV, and antipsoriatic effects. Recent findings indicate that some thio-avarol derivatives exhibit acetylcholinesterase (AChE) inhibitory activity. The multiple pharmacological properties of avarol, thio-avarol and/or their derivatives prompted us to continue the in vitro screening, focusing on their AChE inhibitory and neuroprotective effects. Due to the complex nature of Alzheimer's disease (AD), there is a renewed search for new, non hepatotoxic anticholinesterasic compounds. This paper describes the synthesis and in vitro biological evaluation of avarol-3'-thiosalicylate (TAVA) and thiosalycil-prenyl-hydroquinones (TPHs), as non hepatotoxic anticholinesterasic agents, showing a good neuroprotective effect on the decreased viability of SHSY5Y human neuroblastoma cells induced by oligomycin A/rotenone and okadaic acid. A molecular modeling study was also undertaken on the most promising molecules within the series to elucidate their AChE binding modes and in particular the role played by the carboxylate group in enzyme inhibition. Among them, TPH4, bearing a geranylgeraniol substituent, is the most significant Electrophorus electricus AChE (EeAChE) inhibitor (IC50 = 6.77 ± 0.24 μM), also endowed with a moderate serum horse butyrylcholinesterase (eqBuChE) inhibitory activity, being also the least hepatotoxic and the best neuroprotective compound of the series. Thus, TPHs represents a new family of synthetic compounds, chemically related to the natural compound avarol, which has been discovered for the potential treatment of AD. Findings prove the relevance of TPHs as a new possible generation of competitive AChE inhibitors pointing out the importance of the salycilic substituents on the hydroquinone ring. Since these compounds do not belong to the class of

  18. Curcumin derivatives as metal-chelating agents with potential multifunctional activity for pharmaceutical applications.

    Science.gov (United States)

    Ferrari, Erika; Benassi, Rois; Sacchi, Stefania; Pignedoli, Francesca; Asti, Mattia; Saladini, Monica

    2014-10-01

    Curcuminoids represent new perspectives for the development of novel therapeutics for Alzheimer's disease (AD), one probable mechanism of action is related to their metal complexing ability. In this work we examined the metal complexing ability of substituted curcuminoids to propose new chelating molecules with biological properties comparable with curcumin but with improved stability as new potential AD therapeutic agents. The K2T derivatives originate from the insertion of a -CH2COOC(CH3)3 group on the central atom of the diketonic moiety of curcumin. They retain the diketo-ketoenol tautomerism which is solvent dependent. In aqueous solution the prevalent form is the diketo one but the addition of metal ion (Ga(3+), Cu(2+)) causes the dissociation of the enolic proton creating chelate complexes and shifting the tautomeric equilibrium towards the keto-enol form. The formation of metal complexes is followed by both NMR and UV-vis spectroscopy. The density functional theory (DFT) calculations on K2T21 complexes with Ga(3+) and Cu(2+) are performed and compared with those on curcumin complexes. [Ga(K2T21)2(H2O)2](+) was found more stable than curcumin one. Good agreement is detected between calculated and experimental (1)H and (13)C NMR data. The calculated OH bond dissociation energy (BDE) and the OH proton dissociation enthalpy (PDE), allowed to predict the radical scavenging ability of the metal ion complexed with K2T21, while the calculated electronic affinity (EA) and ionization potential (IP) represent yardsticks of antioxidant properties. Eventually theoretical calculations suggest that the proton-transfer-associated superoxide-scavenging activity is enhanced after binding metal ions, and that Ga(3+) complexes display possible superoxide dismutase (SOD)-like activity.

  19. Synthesis and Biological Evaluation of Norcantharidin Derivatives Possessing an Aromatic Amine Moiety as Antifungal Agents

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2015-12-01

    Full Text Available Based on the structure of naturally produced cantharidin, different arylamine groups were linked to the norcantharidin scaffold to provide thirty six compounds. Their structures were confirmed by melting point, 1H-NMR, 13C-NMR and HRMS-ESI studies. These synthetic compounds were tested as fungistatic agents against eight phytopathogenic fungi using the mycelium growth rate method. Of these thirty six derivatives, seven displayed stronger antifungal activity than did norcantharidin, seven showed higher activity than did cantharidin and three exhibited more significant activity than that of thiabendazole. In particular, 3-(3′-chloro-phenylcarbamoyl norcantharidate II-8 showed the most significant fungicidal activity against Sclerotinia fructigena and S. sclerotiorum, with IC50 values of 0.88 and 0.97 μg/mL, respectively. The preliminary structure-activity relationship data of these compounds revealed that: (1 the benzene ring is critical for the improvement of the spectrum of antifungal activity (3-phenylcarbamoyl norcantharidate II-1 vs norcantharidin and cantharidin; (2 among the three sites, including the C-2′, C-3′ and C-4′ positions of the phenyl ring, the presence of a halogen atom at the C-3′position of the benzene ring caused the most significant increase in antifungal activity; (3 compounds with strongly electron-drawing or electron-donating groups substitutions were found to have a poor antifungal activity; and (4 compared with fluorine, bromine and iodine, chlorine substituted at the C-3′ position of the benzene ring most greatly promoted fungistatic activity. Thus, compound II-8 has emerged as new lead structure for the development of new fungicides.

  20. Study on gadolinium complexes based on polysaccharide derivatives as a contrast agent for MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hashiguchi, Yuji; Seri, Shigemi; Kubomura, Kan; Abe, Yukiko; Kamimura, Kenji; Fujimoto, Chieko; Iguchi, Toshio; Iwai, Kumiko (Nihon Medi-Physics Co., Ltd., Sodegaura, Chiba (Japan))

    1993-05-01

    The authors report new gadolinium compounds, polysaccharide-gadolinium chelate, that have the enhancement property in magnetic resonance imaging (MRI) as well as a longer half-life time in blood. Dialdehyde starch (DAS ; mol. wt. 7 x 10[sup 3]) and dialdehyde amylose (DAA ; mol. wt. 3 x 10[sup 3]) were synthesized to increase the half-life time in blood. The binding of gadolinium to DAS or DAA was facilitated by the newly synthesized bifunctional chelating agents N-[2-bis(carboxymethyl)aminoethyl] -N-[2-bis(carboxymethyl)amino -2(p-benzyl)ethyl]glycine (ABDTPA) and 10-[N-(2-aminoethyl)carbamoyl]methyl-[alpha], [alpha]', [alpha]''-trimethyl-1,4,7,10 -tetraazacyclododecane-1,4,7-triacetic acid (DO 3 MA). The enhancement properties of resulting gadolinium compounds were evaluated for biodistribution, relaxivity and enhancement effect. Biodistribution was examined by use of [sup 111]In labelled complex. Relaxivity was measured at 0.5T and 1.5T. Enhancement effect was examined in vivo by using rats that have brain occlusions. Gadolinium(Gd) complexes with DAS or DAA were found to be staying in the blood vessel for a longer period of time than other existing enhancers. The half-life time of DAS-ABDTPA-Gd is 2h, while as DAA-ABDTPA-Gd is 55 min, eighty to ninety percent of gadolinium complexes bound to DAS or DAA were excreted in urine 24 h after administration. Relaxivities of the above gadolinium complexes were 1.2[approx]2 times as high as those of ABDTPA-Gd or DO 3 MA-Gd. These results demonstrate that gadolinium complexes based on polysaccharide derivatives are promising compounds for future use as MRI enhancers. (author).

  1. Synthesis of some pyrazolines and pyrimidines derived from polymethoxy chalcones as anticancer and antimicrobial agents.

    Science.gov (United States)

    Rostom, Sherif A F; Badr, Mona H; Abd El Razik, Heba A; Ashour, Hayam M A; Abdel Wahab, Abeer E

    2011-09-01

    The synthesis of a series of certain polymethoxy chalcones and some derived pyrazole, pyrimidine, and thiazolopyrimidine ring structures is reported. Eleven compounds 4, 6, 9, 11, 14-17, 22, 24, and 25 were selected by the National Cancer Institute (NCI) to be screened for their in-vitro anticancer activity, whereas all the synthesized compounds were evaluated for their in-vitro antimicrobial activity. Compounds 4, 6, and 11 were found to possess a significant broad spectrum antitumor potential against most of the tested subpanel tumor cell lines. The pyrazolines 4 and 6 displayed remarkable growth inhibitory activities (GI(50) MG-MID values of 2.10 and 1.38 µM, respectively), together with moderate cytostatic effects (TGI MG-MID values of 47.9 and 42.7 µM, respectively). Meanwhile, the pyrimidin-2-one 11 showed a noticeable overall tumor growth inhibitory activity, together with high cytostatic and cytotoxic efficacies (GI(50) , TGI and LC(50) MG-MID values of 3.39, 17.4, and 61.7 µM, respectively). On the other hand, compounds 3, 4, 13, 15, 19, 20, and 23 were found to be the most active antimicrobial members in this investigation with a broad spectrum of activity. Compound 23 was four times superior to ampicillin against Pseudomonas aeruginosa. The best antifungal activity was demonstrated by compounds 4, 5, and 11 which possessed almost half the activity of clotrimazole against Candida albicans. Collectively, the obtained biological results suggest that compound 4 could be considered as a possible dual antimicrobial-anticancer agent.

  2. Isatin Derived Spirocyclic Analogues with α-Methylene-γ-butyrolactone as Anticancer Agents: A Structure-Activity Relationship Study.

    Science.gov (United States)

    Rana, Sandeep; Blowers, Elizabeth C; Tebbe, Calvin; Contreras, Jacob I; Radhakrishnan, Prakash; Kizhake, Smitha; Zhou, Tian; Rajule, Rajkumar N; Arnst, Jamie L; Munkarah, Adnan R; Rattan, Ramandeep; Natarajan, Amarnath

    2016-05-26

    Design, synthesis, and evaluation of α-methylene-γ-butyrolactone analogues and their evaluation as anticancer agents is described. SAR identified a spirocyclic analogue 19 that inhibited TNFα-induced NF-κB activity, cancer cell growth and tumor growth in an ovarian cancer model. A second iteration of synthesis and screening identified 29 which inhibited cancer cell growth with low-μM potency. Our data suggest that an isatin-derived spirocyclic α-methylene-γ-butyrolactone is a suitable core for optimization to identify novel anticancer agents.

  3. Rationality, mental causation and social sciences

    Directory of Open Access Journals (Sweden)

    Mladenović Ivan

    2009-01-01

    Full Text Available The aim of this paper is to investigate the role of mental causation in the context of rational choice theory. The author defends psychological aspect of rational explanation against the challenge of contemporary reductive materialism.

  4. Proteomics Analysis of the Causative Agent of Typhoid Fever

    Energy Technology Data Exchange (ETDEWEB)

    Ansong, Charles; Yoon, Hyunjin; Norbeck, Angela D.; Gustin, Jean K.; McDermott, Jason E.; Mottaz, Heather M.; Rue, Joanne; Adkins, Joshua N.; Heffron, Fred; Smith, Richard D.

    2008-02-01

    Typhoid fever is a potentially fatal disease caused by the bacterial pathogen Salmonella enterica serovar Typhi (S. typhi). S. typhi infection is a complex process that involves numerous bacterially-encoded virulence determinants, and these are thought to confer both stringent human host specificity and a high mortality rate. In the present study we used a liquid chromatography-mass spectrometry (LC-MS) based proteomics strategy to investigate the proteome of logarithmic, stationary phase, and low pH/low magnesium (MgM) S. typhi cultures. This represents the first large scale comprehensive characterization of the S. typhi proteome. Our analysis identified a total of 2066 S. typhi proteins. In an effort to identify putative S. typhi-specific virulence factors, we then compared our S. typhi results to those obtained in a previously published study of the S. typhimurium proteome under similar conditions (Adkins J.N. et al (2006) Mol Cell Prot). Comparative proteomic analysis of S. typhi (strain Ty2) and S. typhimurium (strains LT2 and 14028) revealed a subset of highly expressed proteins unique to S. typhi that were exclusively detected under conditions that mimic the infective state in macrophage cells. These proteins included CdtB, HlyE, and a conserved protein encoded by t1476. The differential expression of selected proteins was confirmed by Western blot analysis. Taken together with the current literature, our observations suggest that this subset of proteins may play a role in S. typhi pathogenesis and human host specificity. In addition, we observed products of the biotin (bio) operon displayed a higher abundance in the more virulent strains S. typhi-Ty2 and S. typhimurium-14028 compared to the virulence attenuated S. typhimurium strain LT2, suggesting bio proteins may contribute to Salmonella pathogenesis.

  5. Voltage-Gated Channels as Causative Agents for Epilepsies

    OpenAIRE

    2008-01-01

    Problem statement: Epilepsy is a common neurological disorder that afflicts 1-2% of the general population worldwide. It encompasses a variety of disorders with seizures. Approach: Idiopathic epilepsies were defined as a heterogeneous group of seizure disorders that show no underlying cause .Voltage-gated ion channels defect were recognized etiology of epilepsy in the central nervous system. The aim of this article was to provide an update on voltage-gated ...

  6. Interaction between mycotoxins and causative agents of swine infective diseases

    OpenAIRE

    Prodanov-Radulović Jasna Z.; Došen Radoslav Đ.; Stojanov Igor M.; Pušić Ivan M.; Živkov-Baloš Milica M.; Ratajac Radomir D.

    2011-01-01

    Mycotoxins are secondary metabolites of fungi that can contaminate animal feeds at all stages of food production chain. Consumption of feed contaminated with mycotoxins may result in immunosuppression, which represents a predisposing factor for occurence of infectious diseases in livestock. The influence on immune system is of special interest in swine industry. The technology on swine farms demands frequent vaccinations, which may be a problem in the case of immunocompromised animals. ...

  7. APPROUSH TO SPECIFIC DIAGNOSTICS OF CAUSATIVE AGENTS OF INFECTIOUS ENDOCARDIDIS

    OpenAIRE

    Katsapov D.V.

    2015-01-01

    Introduction. Increased level of morbidity of infective endocarditis (IE) connected with new risk factors: intravenous drug use, cardiosurgical interventions, hemodialysis brought new clinical forms of the disease. As it shown in a literature main pathogenetic factors of IE are bacteraemia, trauma of endocardium and invasive medical procedures. Very typical pathogens are streptococci and staphylococci. Most typically mitral and aortal valves are affected with spreading...

  8. Salmonella Alachua: causative agent of a foodborne disease outbreak

    Directory of Open Access Journals (Sweden)

    Ivete Aparecida Zago Castanheira de Almeida

    2015-06-01

    Full Text Available Objectives: The aim of this study is to report the occurrence of the first outbreak of food poisoning caused by SalmonellaAlachua in Brazil, as well as the antimicrobial susceptibility and the genetic relatedness of SalmonellaAlachua strains isolated from clinical and food samples.Material and methods: To elucidate the outbreak, an epidemiological investigation was carried out, and two samples of common food were tested - mayonnaise salad and galinhada(a traditional Brazilian dish of chicken and rice - according to the Compendium of methods for the microbiological examination of foods. Five stool samples were tested employing classic methods for the isolation and identification of enterobacteria. Strains of Salmonella were characterized for antibiotic susceptibility according to the Clinical and Laboratory Stan- dards Institute guidelines (2013, and submitted to pulsed-field gel electrophoresis analysis, performed according to the Centers for Disease Control and Prevention PulseNet protocol.Results: A total of 94 people were interviewed after ingesting the food, 66 of whom had become ill. A 60-year old female patient who was hospitalized in a serious condition, developed septic shock and died two days after consuming the food. The presence of SalmonellaAlachua was confirmed in all the analyzed stool samples, and in the two types of food. The five strains showed higher than minimum inhibitory concentration values of nalidixic acid (≥256 µg/mL and reduced ciprofloxacin susceptibility (minimum inhibitory concentration = 0.5 µg/mL. The pulsed-field gel electrophoresis analysis revealed indistinguishable patterns in SalmonellaAlachua strains isolated from clinical and food samples.Conclusion: The data presented herein confirm the foodborne disease outbreak. They also allowed for the identification of the source of infection, and suggest that products from poultry are potential reservoirs for this serotype, reinforcing the importance of warning consumers about the danger of possible contamination.

  9. Effect of Silane Coupling Agent on Tribological Properties of Hemp Fiber-Reinforced Plant-Derived Polyamide 1010 Biomass Composites.

    Science.gov (United States)

    Nishitani, Yosuke; Kajiyama, Tetsuto; Yamanaka, Toshiyuki

    2017-09-05

    We have studied the effects of silane coupling agents used for the surface treatment of fiber on the tribological properties of hemp fiber (HF) reinforced plant-derived polyamide 1010 (PA1010) biomass composites. Hemp fibers were surface-treated by two surface treatment methods: (a) alkali treatment by sodium hydroxide solution and (b) surface treatment by silane coupling agents. Three types of silane coupling agents, namely aminosilane, epoxysilane and ureidosilane were used. These HF/PA1010 biomass composites were extruded using a twin extruder, and injection-molded. The mechanical and tribological properties were evaluated by the ring-on-plate type sliding wear test. It was found that tribological properties of HF/PA1010 biomass composites improved with the surface treatment by the silane coupling agent. This may be attributed to the change in the mode of friction and wear mechanism by the interfacial adhesion between fiber and matrix polymer according to the type of silane coupling agent used. In particular, the ureidosilane coupling agent showed the best improvement effect for the tribological properties of these biomass composites in this study.

  10. Plasma gasification of refuse derived fuel in a single-stage system using different gasifying agents.

    Science.gov (United States)

    Agon, N; Hrabovský, M; Chumak, O; Hlína, M; Kopecký, V; Masláni, A; Bosmans, A; Helsen, L; Skoblja, S; Van Oost, G; Vierendeels, J

    2016-01-01

    The renewable evolution in the energy industry and the depletion of natural resources are putting pressure on the waste industry to shift towards flexible treatment technologies with efficient materials and/or energy recovery. In this context, a thermochemical conversion method of recent interest is plasma gasification, which is capable of producing syngas from a wide variety of waste streams. The produced syngas can be valorized for both energetic (heat and/or electricity) and chemical (ammonia, hydrogen or liquid hydrocarbons) end-purposes. This paper evaluates the performance of experiments on a single-stage plasma gasification system for the treatment of refuse-derived fuel (RDF) from excavated waste. A comparative analysis of the syngas characteristics and process yields was done for seven cases with different types of gasifying agents (CO2+O2, H2O, CO2+H2O and O2+H2O). The syngas compositions were compared to the thermodynamic equilibrium compositions and the performance of the single-stage plasma gasification of RDF was compared to that of similar experiments with biomass and to the performance of a two-stage plasma gasification process with RDF. The temperature range of the experiment was from 1400 to 1600 K and for all cases, a medium calorific value syngas was produced with lower heating values up to 10.9 MJ/Nm(3), low levels of tar, high levels of CO and H2 and which composition was in good agreement to the equilibrium composition. The carbon conversion efficiency ranged from 80% to 100% and maximum cold gas efficiency and mechanical gasification efficiency of respectively 56% and 95%, were registered. Overall, the treatment of RDF proved to be less performant than that of biomass in the same system. Compared to a two-stage plasma gasification system, the produced syngas from the single-stage reactor showed more favourable characteristics, while the recovery of the solid residue as a vitrified slag is an advantage of the two-stage set-up.

  11. Food coloring agents and plant food supplements derived from Vitis vinifera: a new source of human exposure to ochratoxin A.

    Science.gov (United States)

    Solfrizzo, Michele; Piemontese, Luca; Gambacorta, Lucia; Zivoli, Rosanna; Longobardi, Francesco

    2015-04-08

    Grape pomaces are increasingly being used as starting material in the industrial production of plant food supplements (PFS), food coloring, and tartrates, but they are at risk of ochratoxin A (OTA) contamination, a mycotoxin with nephrotoxic and carcinogenic effects. We analyzed 24 commercial PFS and 13 food coloring samples derived from Vitis vinifera, mainly pomaces, using a HPLC-FLD method for OTA determination. OTA was found in 75% of PFS samples and 69% of food coloring samples at levels of food coloring agents derived from V. vinifera suggests that maximum permitted level(s) should be established for this mycotoxin in these products.

  12. Novel N-(pyrimidin-4-ylthiazol-2-amine derivatives as dual-action hypoglycemic agents that activate GK and PPARγ

    Directory of Open Access Journals (Sweden)

    Hui-peng Song

    2011-10-01

    Full Text Available A series of novel N-(pyrimidin-4-ylthiazol-2-amine derivatives have been synthesized and evaluated as glucokinase (GK activators. Ethyl 2-(6-(4-(2-hydroxyethylpiperazin-1-yl-2-methylpyrimidin-4-yl-aminothiazole-5-carboxylate was found to be a potent dual-acting hypoglycemic agent activating both GK and PPARγ. When given orally to normal mice, the compound demonstrated significant efficacy in decreasing the glucose level after oral glucose loading.

  13. Design, synthesis, and evaluation of carnosine derivatives as selective and efficient sequestering agents of cytotoxic reactive carbonyl species.

    Science.gov (United States)

    Vistoli, Giulio; Orioli, Marica; Pedretti, Alessandro; Regazzoni, Luca; Canevotti, Renato; Negrisoli, Gianpaolo; Carini, Marina; Aldini, Giancarlo

    2009-06-01

    Carnosine aryl derivatives as sequestering agents of RCS: Reactive carbonyl species (RCS) are cytotoxic mediators representing a novel drug target, as they are presumed to play a pathogenic role in several diseases. Carnosine is a selective RCS-sequestering agent, but is rapidly hydrolyzed by serum carnosinase. Herein we describe the in silico design, synthesis, and evaluation of a set of carnosine aryl derivatives.Reactive carbonyl species (RCS) are important cytotoxic mediators generated by lipid oxidation of polyunsaturated fatty acids (PUFAs) and represent a novel drug target, as they are presumed to play a pathogenic role in several diseases. L-Carnosine (L-CAR, beta-alanyl-L-histidine) is a specific detoxifying agent of RCS, but is rapidly hydrolyzed in human serum by carnosinase, a specific dipeptidase. Herein we describe the in silico design, synthesis, and biological evaluation of carnosine derivatives that are resistant to carnosinase and that have increased quenching efficacy. Stability against carnosinase-mediated turnover was achieved by isomerization of the histidine residue, leading to D-carnosine (D-CAR, beta-alanyl-D-histidine), which maintains the same quenching activity of L-carnosine. A molecular modeling approach was then used to design derivatives characterized by an increased quenching efficacy. The most promising candidates were synthesized, and their stability and quenching activity were evaluated. This study describes a set of aryl derivatives that are characterized by high stability in human plasma and a quenching activity toward 4-hydroxy-trans-2-nonenal (HNE), chosen as a model of RCS, up to threefold greater than D-carnosine.

  14. Iconicity of cohesion in Persian causative constructions

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Salmani Nodoushan

    2014-12-01

    Full Text Available This paper tries to show that Persian causative constructions are not only iconic in nature but also employ iconicity of cohesion in their syntactic structures productively. It starts with a description of iconicity and specifically focuses on the notion of conceptual distance as discussed by Haiman (1983. It then briefly reviews the formal typology of causative constructions (i. e., lexical, morphological, and periphrastic and summarizes the ideas proposed by Comrie (1989, Dixon (2000, Shibatani (1976, and Talmy (2003 to come up with a list of, and a table for, the semantic properties of causative constructions (i. e., directness, coercion, control, manipulation, separability, and clause structure. The paper then presents tangible evidence and examples from Persian to claim that the linguistic distance observed between [Vcause] and [Veffect] in different types of Persian causative constructions mirrors the conceptual distance between them, and concludes that the iconic nature of causative constructions in Persian can be explained on the basis of the principle of iconicity of cohesion. It lends support to the universality of the principles of functional-cognitive linguistics and shows that iconicity theory still has a high potential for explaining form-meaning relations in different syntactic structures.

  15. The synthesis of a water-soluble derivative of rutin as an antiradical agent

    Energy Technology Data Exchange (ETDEWEB)

    Pedriali, Carla Aparecida; Fernandes, Adjaci Uchoa [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Quimica. Dept. de Bioquimica]. E-mail: capedriali@hotmail.com; Bernusso, Leandra de Cassia; Polakiewicz, Bronislaw [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Tecnologia Bioquimico-Farmaceutica

    2008-07-01

    The purpose of this study was to synthesize a water-soluble derivative of rutin (compound 2) by introducing carboxylate groups on rutin's sugar moiety. The rutin derivative showed an almost 100-fold solubility increase in water. The antiradical capacity of compound 2 was evaluated using the luminol/AAPH system, and the derivative's activity was 1.5 times greater than that of Trolox. Despite the derivative's high solubility in water (log P = -1.13), lipid peroxidation of brain homogenate membranes was very efficiently inhibited (inhibition values were only 19% lower than the inhibition values of rutin). (author)

  16. Identification of myeloproliferative neoplasm drug agents via predictive simulation modeling: assessing responsiveness with micro-environment derived cytokines.

    Science.gov (United States)

    Kobayashi, Susumu S; Vali, Shireen; Kumar, Ansu; Singh, Neeraj; Abbasi, Taher; Sayeski, Peter P

    2016-06-14

    Previous studies have shown that the bone marrow micro-environment supports the myeloproliferative neoplasms (MPN) phenotype including via the production of cytokines that can induce resistance to frontline MPN therapies. However, the mechanisms by which this occurs are poorly understood. Moreover, the ability to rapidly identify drug agents that can act as adjuvants to existing MPN frontline therapies is virtually non-existent. Here, using a novel predictive simulation approach, we sought to determine the effect of various drug agents on MPN cell lines, both with and without the micro-environment derived inflammatory cytokines. We first created individual simulation models for two representative MPN cell lines; HEL and SET-2, based on their genomic mutation and copy number variation (CNV) data. Running computational simulations on these virtual cell line models, we identified a synergistic effect of two drug agents on cell proliferation and viability; namely, the Jak2 kinase inhibitor, G6, and the Bcl-2 inhibitor, ABT737. IL-6 did not show any impact on the cells due to the predicted lack of IL-6 signaling within these cells. Interestingly, TNFα increased the sensitivity of the single drug agents and their use in combination while IFNγ decreased the sensitivity. In summary, this study predictively identified two drug agents that reduce MPN cell viability via independent mechanisms that was prospectively validated. Moreover, their efficacy is either potentiated or inhibited, by some of the micro-environment derived cytokines. Lastly, this study has validated the use of this simulation based technology to prospectively determine such responses.

  17. Laws, Causation and Dynamics at Different Levels

    CERN Document Server

    Butterfield, Jeremy

    2014-01-01

    I have two main aims. The first is general, and more philosophical (Section 2). The second is specific, and more closely related to physics (Sections 3 and 4). The first aim is to state my general views about laws and causation at different 'levels'. The main task is to understand how the higher levels sustain notions of law and causation that 'ride free' of reductions to the lower level or levels. I endeavour to relate my views to those of other symposiasts. The second aim is to give a framework for describing dynamics at different levels, emphasising how the various levels' dynamics can mesh or fail to mesh. This framework is essentially that of elementary dynamical systems theory. The main idea will be, for simplicity, to work with just two levels, dubbed 'micro' and 'macro' which are related by coarse-graining. I use this framework to describe, in part, the first four of Ellis' five types of top-down causation.

  18. Structure-activity relationship analysis of novel derivatives of narciclasine (an Amaryllidaceae isocarbostyril derivative) as potential anticancer agents.

    Science.gov (United States)

    Ingrassia, Laurent; Lefranc, Florence; Dewelle, Janique; Pottier, Laurent; Mathieu, Véronique; Spiegl-Kreinecker, Sabine; Sauvage, Sébastien; El Yazidi, Mohamed; Dehoux, Mischaël; Berger, Walter; Van Quaquebeke, Eric; Kiss, Robert

    2009-02-26

    Narciclasine (1) is a plant growth regulator that has been previously demonstrated to be proapoptotic to cancer cells at high concentrations (> or = 1 microM). Data generated in the present study show that narciclasine displays potent antitumor effects in apoptosis-resistant as well as in apoptosis-sensitive cancer cells by impairing the organization of the actin cytoskeleton in cancer cells at concentrations that are not cytotoxic (IC(50) values of 30-90 nM). The current study further revealed that any chemical modification to the narciclasine backbone generally led to compounds of variable stability, weaker activity, or even the complete loss of antiproliferative effects in vitro. However, one hemisynthetic derivative of narciclasine, compound 7k, demonstrated by both the intravenous and oral routes higher in vivo antitumor activity in human orthotopic glioma models in mice when compared to narciclasine at nontoxic doses. Narciclasine and compound 7k may therefore be of potential use to combat brain tumors.

  19. Natural product derived antiprotozoal agents: synthesis, biological evaluation, and structure-activity relationships of novel chromene and chromane derivatives.

    Science.gov (United States)

    Harel, Dipak; Schepmann, Dirk; Prinz, Helge; Brun, Reto; Schmidt, Thomas J; Wünsch, Bernhard

    2013-09-26

    Various natural products with the chromane and chromene scaffold exhibit high antiprotozoal activity. The natural product encecalin (7) served as key intermediate for the synthesis of different ethers 9, amides 11, and amines 12. The chromane analogues 14 and the phenols 15 were obtained by reductive amination of ketones 13 and 6, respectively. Angelate 3, ethers 9, and amides 11 did not show considerable antiprotozoal activity. However, the chromene and chromane derived amines 12, 14, and 15 revealed promising antiprotozoal activity and represent novel lead compounds. Whereas benzylamine 12a and α-methylbenzylamine 12g were active against P. falciparum with IC50 values in the range of chloroquine, the analogous phenols 15a and 15b were unexpectedly 10- to 25-fold more potent than chloroquine with selectivity indexes of 6760 and 1818, respectively. The phenylbutylamine 14d based on the chromane scaffold has promising activity against T. brucei rhodesiense and L. donovani.

  20. Podophyllotoxin-derived insecticidal agents: part XIII--evaluation of insecticidal activity of podophyllotoxin derivatives against Brontispa longissima.

    Science.gov (United States)

    Liu, Ying-Qian; Feng, Gang; Yang, Liu; Jing-Zhang; Li, Hong-Yu

    2011-09-01

    In an attempt to find the biorational insecticides for Brontispa longissima control, 12 podophyllotoxin (PPT) analogues were tested for their insecticidal activity against the fifth-instar larvae of B. longissima in vivo for the first time. Among all the tested compounds, especially compounds 6 and 8 showed more promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach. The different insecticidal activity range of compounds 1-12 indicated that the variation of chemical structures in the PPT skeleton markedly affected the activity profiles of this compound class, and some important structure-activity relationship information has been revealed. Together, these preliminary results may be useful in guiding further modification of PPTs in the development of potential new insecticides.

  1. Identification of Onosma visianii Roots Extract and Purified Shikonin Derivatives as Potential Acaricidal Agents against Tetranychus urticae.

    Science.gov (United States)

    Sut, Stefania; Pavela, Roman; Kolarčik, Vladislav; Cappellacci, Loredana; Petrelli, Riccardo; Maggi, Filippo; Dall'Acqua, Stefano; Benelli, Giovanni

    2017-06-16

    There is an increasing need for the discovery of reliable and eco-friendly pesticides and natural plant-derived products may play a crucial role as source of new active compounds. In this research, a lipophilic extract of Onosma visianii roots extract containing 12% of shikonin derivatives demonstrated significant toxicity and inhibition of oviposition against Tetranychus urticae mites. Extensive chromatographic separation allowed the isolation of 11 naphthoquinone derivatives that were identified by spectral techniques and were tested against Tetranychus urticae. All the isolated compounds presented effects against the considered mite and isobutylshikonin (1) and isovalerylshikonin (2) were the most active, being valuable model compounds for the study of new anti-mite agents.

  2. Chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents

    NARCIS (Netherlands)

    Molhoek, E.M.; van Dijk, A.; Veldhuizen, E.J.A.; Dijk-Knijnenburg, H.; Mars-Groenendijk, R.H.; Boele, L.C.L.; Kaman, W.E.; Haagsman, H.P.; Bikker, F.J.

    2010-01-01

    Host defence peptides (HDPs) are considered to be excellent candidates for the development of novel therapeutic agents. Recently, it was demonstrated that the peptide C1-15, an N-terminal segment of chicken HDP cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards

  3. Genotoxicity study of a new tetraalkylammonium derivative of 6-methyluracil (agent No. 547).

    Science.gov (United States)

    Karamova, Nazira S; Ivanchenko, Olga B; Ilinskaya, Olga N; Zobov, Vladimir V; Reznik, Vladimir S

    2002-03-01

    Agent No. 547 (1,3-bis[omega-(diethyl-ortho-nitrobenzylammonio)-pentyl]-6-methyluracil dibromide), a newly synthesized inhibitor of mammalian-specific acetyltcholinesterase (EC 3.1.1.7) was investigated for genotoxicity using the DNA-repair test, Ames test and in vivo micronucleus test with mouse peripheral blood erythrocytes. Agent No. 547 did not cause significant changes in growth of repair-deficient Escherichia coli tester strains. The compound was non-mutagenic in Salmonella typhimurium strains TA98 and TA100 with and without rat microsomal activation mixture. However, we observed a marked increase in number of His(+) revertants for both tester strains in preincubation assays. The results obtained in the micronucleus test indicate that agent No. 547 possesses significant clastogenic activity. At the high dose tested (0.5 mg/kg), the compound induced a seven-fold increase in the number of micronuclei over the spontaneous background 48 h after treatment. The results suggest that further work should be promoted to identify the metabolic pathways involved in genotoxicity of agent No. 547 in mammalian cells and to evaluate the real risk of its exposure.

  4. Chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents

    NARCIS (Netherlands)

    Molhoek, E.M.; Dijk, A. van; Veldhuizen, E.J.A.; Dijk-Knijnenburg, H.; Mars-Groenendijk, R.H.; Boele, L.C.L.; Kaman-van Zanten, W.E.; Haagsman, H.P.; Bikker, F.J.

    2010-01-01

    Host defence peptides (HDPs) are considered to be excellent candidates for the development of novel therapeutic agents. Recently, it was demonstrated that the peptide C1-15, an N-terminal segment of chicken HDP cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards

  5. Synthesis and biological evaluation of novel gigantol derivatives as potential agents in prevention of diabetic cataract

    Science.gov (United States)

    As a continuation of our efforts directed towards the development of natural anti-diabetic cataract agents, gigantol was isolated from Herba dendrobii and was found to inhibit both aldose reductase (AR) and inducible nitric oxide synthase (iNOS) activity, which play a significant role in the develop...

  6. Anti-cancer agents based on 6-trifluoromethoxybenzimidazole derivatives and method of making

    Science.gov (United States)

    Gakh, Andrei A.; Vovk, Mykhaylo V.; Mel'nychenko, Nina V.; Sukach, Volodymyr A.

    2012-08-14

    The present disclosure relates to novel compounds having the structural Formulas (1a,1b), stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof as chemotherapy agents for treating of cancer, particularly androgen-independent prostate cancer. The disclosure also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  7. Febrile Seizure: Demographic Features and Causative Factors

    OpenAIRE

    2012-01-01

    How to cite this article: Esmaili Gourabi H, Bidabadi E, Cheraghalipour  F, Aarabi  Y, Salamat F. Febrile Seizure: Demographic Features and Causative Factors. Iran J Child Neurol Autumn 2012; 6(4):33-37.Abstract Objective Because of geographical and periodical variation, we prompted to determine the demographic features and causative factors for febrile seizure in Rasht. Materials & Methods In this cross-sectional study, all 6–month- to 6-year-old children with the diagnosis of febrile s...

  8. Cryptolepine Derivatives:Quadruplex-Interactive Agents as Inhibitors of Human Telomerase

    Institute of Scientific and Technical Information of China (English)

    HUANG,Zhi-Shu; ZHOU,Jin-Lin; LU,Yu-Jing; GU,Lian-Quan

    2004-01-01

    @@ Alkaloids are very important natural products. Most of them have biologic activity. Many novel drugs have been developed based on alkaloids, such as camptothecin, taxol, vinblastine. A series of novel cryptolepine derivatives were synthesized (Figure 1). The interaction of cryptolepine derivatives with G-quadruplex (Figure 2) was studied by CD and UV spectra.[1] Most of these compounds can induce the formation of G-quadruplex and stabilize the formed G-quadruplex, resulting in the inhibitory effect on telomerase. Most of these cryptolepine derivatives have potent cytotoxicity in vitro against human tumor cell line.

  9. Synthesis and Biological Evaluation of Metronidazole Derivatives as Anti-Giardia Agents

    Directory of Open Access Journals (Sweden)

    Bahador Shahriari

    2015-06-01

    Full Text Available Nitroimidazole derivatives such as Metronidazole (MTZ have been used as anti- protozoa and anti-anaerobic bacteria. In this study several derivatives of MTZ were synthesized and evaluated against Giardia lamblia cyst. MTZ were reacted with several alkyl halide to obtain o-alkyl MTZ derivatives, then products were purified and their chemical structures were confirmed by spectral analysis (1HNMR and Mass. In order to assess biological evaluation, all compounds were investigated against 25 Giardia samples isolated from Giardia-infected patients. Results showed that compound 2 had the most activity on cyst of Giardia in comparison with MTZ.

  10. Vitamin a derivatives labelled with 131I — Potential agents for liver scientigraphy

    Science.gov (United States)

    Kadeřávek, J.; Kozempel, J.; Štícha, M.; Petrášek, J.; Jirsa, M.; Taimr, P.; Lešetický, L.

    2006-01-01

    Two retinol derivatives, 4-[(131I)-4-iodobenzoyloxy]retinol propionate and 4-[(131I)-3-iodobenzylcarbamoyl]retinol propionate, were synthesized and their biodistribution in rats was studied in vivo by the whole body scintigraphy.

  11. Synthesis of N-substituted aminoalkyl derivatives of some epoxyisoindoles as potential pharmacological agents.

    Science.gov (United States)

    Kossakowski, Jerzy; Raszkiewicz, Aldona

    2005-01-01

    Grogan and Rice reported a number of imides of epoxyisoindole sort. Some pharmacological testing was performed which revealed their bioactivity. Except of their work, only scattered examples of derivatives with oxygen-bridged ring have appeared in the literature; this approach has also been used by us in the synthesis of some new potential drugs. This paper reports the synthesis of a number of epoxyisoindole derivatives, as well as in vitro tests of some selected representants.

  12. PRENYLATED BENZOIC ACID DERIVATIVES FROM PIPER SPECIES AS SOURCE OF ANTI-INFECTIVE AGENTS

    OpenAIRE

    2012-01-01

    A number of prenylated benzoic acids derivatives with interesting biological activities have been previously isolated and characterized from different species of piperaceae family. Several Piper species contained structurally similar compounds with diverse biological activities such as anti-bacterial, anti-fungal, insecticidal as well as anti-parasitic all of which produces compounds that can be classified as prenylated benzoic acid derivatives. Piper sp has proven to serve as a source of pot...

  13. Benzothiazole derivatives bearing amide moiety: potential cytotoxic and apoptosis-inducing agents against cervical cancer.

    Science.gov (United States)

    Singh, Meenakshi; Modi, Arusha; Narayan, Gopeshwar; Singh, Sushil K

    2016-07-01

    Cervical cancer is a major cause of morbidity and mortality in women worldwide. In recent years, benzothiazole analogues have attracted considerable attention in anticancer research. Therefore, in this study, the earlier reported amide series of benzothiazole derivatives were investigated for their antiproliferative activity. The activity of amide derivatives was evaluated using the 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometric analysis, apoptosis assay, and DNA fragmentation on two human cervical cancer cell lines: SiHa and C33-A. The data reported from this investigation indicated that benzothiazole derivatives show pronounced cytotoxicity in the HPV16-positive SiHa cells compared with HPV-negative C-33A cells. The in-vitro cytotoxicity of the compounds on the HEK-293 noncancer cell line was evaluated to establish selectivity. Cells treated with benzothiazole derivatives showed prominent morphological features as evidenced by cell shrinkage, membrane blebbing, apoptotic nuclei, and DNA fragmentation. The benzothiazole derivatives show accumulation of cells in the sub-G1 and S-phase of the cell cycle in SiHa and C33-A, respectively. In addition, these derivatives exert their beneficial effect by inducing apoptosis, in the chemoprevention of cervical cancer cells, and were further ascertained using a DNA fragmentation assay. The compounds studied showed potent cytotoxic and apoptotic properties against SiHa and C33-A cancer cell lines and thus represent an excellent starting point for further optimization of therapeutically effective anticancer drugs.

  14. Potential New Pharmacological Agents Derived From Medicinal Plants for the Treatment of Pancreatic Cancer.

    Science.gov (United States)

    Azimi, Haniye; Khakshur, Ali Asghar; Abdollahi, Mohammad; Rahimi, Roja

    2015-01-01

    In the present article, we reviewed plants and phytochemical compounds demonstrating beneficial effects in pancreatic cancer to find new sources of pharmaceutical agents. For this purpose, Scopus, PubMed, Web of Science, and Google scholar were searched for plants or herbal components with beneficial effects in the treatment of pancreatic cancer. Data were collected up to January 2013. The search terms were "plant," "herb," "herbal therapy," or "phytotherapy" and "pancreatic cancer" or "pancreas." All of the human in vivo and in vitro studies were included. According to studies, among diverse plants and phytochemicals, 12 compounds including apigenin, genistein, quercetin, resveratrol, epigallocatechin gallate, benzyl isothiocyanate, sulforaphane, curcumin, thymoquinone, dihydroartemisinin, cucurbitacin B, and perillyl alcohol have beneficial action against pancreatic cancer cells through 4 or more mechanisms. Applying their plausible synergistic effects can be an imperative approach for finding new efficient pharmacological agents in the treatment of pancreatic cancer.

  15. Evolution in Medicinal Chemistry of Ursolic Acid Derivatives as Anticancer Agents

    OpenAIRE

    Chen, Haijun; Gao, Yu; Wang, Ailan; Zhou, Xiaobin; Zheng, Yunquan; Zhou, Jia

    2015-01-01

    Currently, there is a renewed interest in common dietaries and plant-based traditional medicines for the prevention and treatment of cancer. In the search for potential anticancer agents from natural sources, ursolic acid (UA), a pentacyclic triterpenoid widely found in various medicinal herbs and fruits, exhibits powerful biological effects including its attractive anticancer activity against various types of cancer cells. However, the limited solubility, rapid metabolism and poor bioavailab...

  16. [Causation, prevention and treatment of dust explosion].

    Science.gov (United States)

    Dong, Maolong; Jia, Wenbin; Wang, Hongtao; Han, Fei; Li, Xiao-Qiang; Hu, Dahai

    2014-10-01

    With the development of industrial technology, dust explosion accidents have increased, causing serious losses of people's lives and property. With the development of economy, we should lay further emphasis on causation, prevention, and treatment of dust explosion. This article summarizes the background, mechanism, prevention, and treatment of dust explosion, which may provide some professional knowledge and reference for the treatment of dust explosion.

  17. Design, synthesis and biological evaluation of novel bergapten derivatives as potent lipid lowering agents

    Directory of Open Access Journals (Sweden)

    Jian-Hong Lu

    2015-03-01

    Full Text Available The aim of this study was to synthesize novel amide derivatives of bergapten and evaluate their lipid-lowering and triglyceride-lowering activities in mice. Amide derivatives of bergapten were synthesized by using lactone ring opening strategy in DMSO using NaOH as base followed by alkylation in presence of methyl iodide. The compounds were subjected to preliminary in vivo screening. Fenofibrate (30 mg/kg/day was used as positive controls in this assay. The lipid lowering activity was evaluated using in vivo Triton model and Triton WR-1339 was used as positive control. Most of the synthesized analogs displayed remarkable plasma triglyceride-lowering activity. Compound 5 showed the best activity with (41% triglyceride lowering activity. This compound also exhibited the most potent lipid lowering activity displaying 33%, 32% and 29% lowering in total cholesterol, phospholipids, and triglycerides, respectively. The other derivatives showed almost comparable activity with that of the parent molecule.

  18. Synthesis and biological evaluation of some new amide moiety bearing quinoxaline derivatives as antimicrobial agents.

    Science.gov (United States)

    Abu Mohsen, U; Yurttaş, L; Acar, U; Özkay, Y; Kaplacikli, Z A; Karaca Gencer, H; Cantürk, Z

    2015-05-01

    In this study, we aimed to synthesize some new quinoxaline derivatives bearing amide moiety and to evaluate their antimicrobial activity. A set of 16 novel compounds of N-[2,3-bis(4-methoxy/methylphenyl)quinoxalin-6-yl]-substituted benzamide derivatives were synthesized by reacting 2,3-bis(4-methoxyphenyl)-6-aminoquinoxaline or 2,3-bis(4-methylphenyl)-6-aminoquinoxaline with benzoyl chloride derivatives in tetrahydrofuran and investigated for their antimicrobial activity. The structures of the obtained final compounds were confirmed by spectral data (IR, (1)H-NMR, (13)C-NMR and MS). The antimicrobial activity of the compounds were determined by using the microbroth dilution method. Antimicrobial activity results revealed that synthesized compounds exhibited remarkable activity against Candida krusei (ATCC 6258) and Candida parapsilosis (ATCC 22019).

  19. 4-Hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester derivatives as potent anti-tumor agents.

    Science.gov (United States)

    Hayakawa, Ichiro; Shioya, Rieko; Agatsuma, Toshinori; Furukawa, Hidehiko; Naruto, Shunji; Sugano, Yuichi

    2004-01-19

    Based on the structure of 4-hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester (1), which exhibits selective cytotoxicity against a tumorigenic cell line, (2,4-dimethoxyphenyl)-(4-hydroxy-3-methyl-6-phenylbenzofuran-2-yl)-methanone (18m) was designed and synthesized as a biologically stable derivative containing no ester group. Although the potency of 18m was almost the same as our initial hit compound 1, 18m is expected to last longer in the human body as an anticancer agent.

  20. Medicinal attributes of pyrazolo[1,5-a]pyrimidine based scaffold derivatives targeting kinases as anticancer agents

    Directory of Open Access Journals (Sweden)

    Nasser S.M. Ismail

    2016-12-01

    Full Text Available Pyrazolo pyrimidines are fused heterocyclic ring systems which known as bioisosteres of adenine, that are necessary for every aspect of cell life. Pyrazolo[1,5-a]pyrimidines derivatives have been explored for their inhibitory activity towards a variety of protein kinase enzymes and their function as anticancer agents. This review to the best of our knowledge is the first assemblage on synthesis and medicinal aspects including structure activity relationships of pyrazolo[1,5-a]pyrimidines reported to date.

  1. Polycyclic Aromatic Compounds as Anticancer Agents: Synthesis and Biological Evaluation of Methoxy Dibenzofluorene Derivatives

    Directory of Open Access Journals (Sweden)

    Bimal Krishna Banik

    2014-08-01

    Full Text Available Synthesis of a new methoxy dibenzofluorene through alkylation, cyclodehydration and aromatization in a one-pot operation is achieved for the first time. Using this hydrocarbon, a few derivatives are prepared through aromatic nitration, catalytic hydrogenation, coupling reaction with a side chain and reduction. The benzylic position of this hydrocarbon with the side chain is oxidized and reduced. Some of these derivatives have demonstrated excellent antitumor activities in vitro. This study confirms antitumor activity depends on the structures of the molecules.

  2. Motuporamine Derivatives as Antimicrobial Agents and Antibiotic Enhancers against Resistant Gram‐Negative Bacteria

    Science.gov (United States)

    Borselli, Diane; Blanchet, Marine; Bolla, Jean‐Michel; Muth, Aaron; Skruber, Kristen

    2017-01-01

    Abstract Dihydromotuporamine C and its derivatives were evaluated for their in vitro antimicrobial activities and antibiotic enhancement properties against Gram‐negative bacteria and clinical isolates. The mechanism of action of one of these derivatives, MOTU‐N44, was investigated against Enterobacter aerogenes by using fluorescent dyes to evaluate outer‐membrane depolarization and permeabilization. Its efficiency correlated with inhibition of dye transport, thus suggesting that these molecules inhibit drug transporters by de‐energization of the efflux pump rather than by direct interaction of the molecule with the pump. This suggests that depowering the efflux pump provides another strategy to address antibiotic resistance. PMID:28098416

  3. Synthesis of benzoxazole derivatives of honokiol as insecticidal agents against Mythimna separata Walker.

    Science.gov (United States)

    Yang, Chun; Zhi, Xiaoyan; Xu, Hui

    2015-01-01

    A series of novel benzoxazole compounds derived from a naturally occurring neolignan honokiol were prepared. Their insecticidal activity was tested against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker) in vivo. Most of the tested derivatives exhibited more potential insecticidal activity than their precursor honokiol at the concentration of 1mg/mL. Especially compound 6e, containing 4-acetyloxyphenyl groups at the C8 and C8' positions, displayed the most potent insecticidal activity with the final mortality rate of 62.1%.

  4. Synthesis of Some Phenylpyrazolo Benzimidazolo Quinoxaline Derivatives as Potent Antihistaminic Agents

    Directory of Open Access Journals (Sweden)

    C. H. Sridevi

    2010-01-01

    Full Text Available 2,3-Diphenyl quinoxaline (NI was fused with benzimidazole (NII by a methylene bridge, which was then allowed for acetylation. The acetylated product (NIV was made to react with different aromatic aldehydes to give chalcones (NV1-NV5. Chalcones refluxed with substituted acid hydrazides to afford different phenyl pyrazolo benzimidazole quinoxaline derivatives (NVI 1-NVI 15. The structure of chalcones and phenyl pyrazolo benzimidazole quinoxaline derivatives were confirmed by m.p, TLC and spectral data. All the synthesized compounds were screened for their antihistaminic activity. Compounds NVI-3, NVI-12, NVI-13, NVI-14 and NVI-15 were shown good % protection of antihistamic activity.

  5. Piperidine-mediated synthesis of thiazolyl chalcones and their derivatives as potent antimicrobial agents.

    Science.gov (United States)

    Venkatesan, P; Maruthavanan, T

    2012-01-01

    A series of new thiazolyl chalcones, 1-[2-amino-4-methyl-1,3-thiazol-5-yl]-3-aryl-prop-2-en-1-one were prepared by piperidine mediated Claisen-Schmidt condensation of thiazolyl ketone with aromatic aldehyde. These chalcones on cyclisation gave 2-amino-6-(2-amino-4-methyl-1,3-thiazol-5-yl)-4-aryl-4H-pyridine-3-carbonitrile and 2-amino-6-(2-amino-4-methyl-1,3-thiazol-5-yl)-4-aryl-4H-pyran-3-carbonitrile. The result showed that the compounds exhibited marked potency as antimicrobial agents.

  6. Synthesis and pharmacological evaluation of pyrazolopyrimidopyrimidine derivatives: anti-inflammatory agents with gastroprotective effect in rats

    OpenAIRE

    2013-01-01

    We report the synthesis of new anti-inflammatory 1,7-dihydropyrazolo[3′,4′:4,5]pyrimido[1,6-a]pyrimidine 5 from aminocyanopyrazole. All compounds were characterized by physical, chemical and spectral studies. Preliminary pharmacological evaluation of the resulting products showed that compounds 5a, b, f (50–100 mg/kg, i.p) are active anti-inflammatory agents in carrageenan-induced rat paw oedema assay, and their effects are comparable to that of acetylsalicylic–lysine (300 mg/kg, i.p.), used ...

  7. Synthesis and Screening of Some New N-Substituted Derivatives of N-(4-Methylpyridin-2-ylbenzenesulfonamides as Potential Antibacterial Agents

    Directory of Open Access Journals (Sweden)

    Aziz-ur-Rehman

    2014-03-01

    Full Text Available The two step synthesis of a series of N-substituted derivatives of N-(4-Methylpyridin-2-ylbenzenesulfonamide with potential antibacterial activity, has been reported. First step includes the synthesis of N-(4-Methylpyridin-2-ylbenzenesulfonamide (3 by reaction of 2-Amino-4-methylpyridine (1 and Benzenesulfonyl chloride (2 in a slightly basic aqueous medium. The molecule 3 was converted to N-Alkyl/aralkyl-N-(4-methylpyridin-2-ylbenzenesulfonamide derivatives, 5a-f, on treatment with alkyl/aralkyl halides, 4a-f, using lithium hydride as activator in N,N-dimethylformamide. The synthesized molecules were well corroborated by 1H-NMR, IR and EI-MS spectral data and evaluated for antibacterial activity against four gram-negative and two gram-positive bacteria. The evaluation results rendered these compounds as moderately good inhibitors and may be employed as therapeutic agent for certain inflammatory ailments.

  8. Semisynthesis and quantitative structure-activity relationship (QSAR) study of some cholesterol-based hydrazone derivatives as insecticidal agents.

    Science.gov (United States)

    Yang, Chun; Shao, Yonghua; Zhi, Xiaoyan; Huan, Qu; Yu, Xiang; Yao, Xiaojun; Xu, Hui

    2013-09-01

    In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, four series of novel cholesterol-based hydrazone derivatives were synthesized, and their insecticidal activity was tested against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1mg/mL. All the derivatives showed the better insecticidal activity than their precursor cholesterol. Quantitative structure-activity relationship (QSAR) model demonstrated that six descriptors such as RDF085v, Mor06u, Mor11u, Dv, HATS0v and H-046, are likely to influence the insecticidal activity of these compounds. Among them, two important ones are the Mor06u and RDF085v.

  9. Novel pleuromutilin derivatives as antibacterial agents: synthesis, biological evaluation and molecular docking studies.

    Science.gov (United States)

    Wang, Xinyang; Ling, Yong; Wang, Hui; Yu, Jianghe; Tang, Junming; Zheng, Heng; Zhao, Xi; Wang, Donggeng; Chen, Guangtong; Qiu, Wenqian; Tao, Jinhua

    2012-10-01

    Owing to the increasingly serious problems caused by multidrug resistance in community-acquired infection pathogens, it has become an urgent need to develop new classes of antibiotics for overcoming the resistance. In this paper, we describe the design and synthesis of novel pleuromutilin derivatives containing the (2-aminothiazol-4-yl)-4-methyl group, as well as their in vitro antibacterial activities against Gram-positive clinical bacteria. Most of the tested compounds displayed strong antibacterial activities against these methicillin-susceptible and methicillin-resistant bacteria. Particularly noteworthy compound 15 and its derivative 16e, both showed potent antibacterial properties (0.0625-0.5μg/mL) that are superior to amoxicillin and tiamulin. Molecular docking studies suggested that the amino thiazole ring on the side chains of the pleuromutilin derivatives can in general be accommodated near the mutilin core in the binding pocket, and thus play an important role in the activity of the whole molecule. The findings reported herein may provide a new insight into the design of novel pleuromutilin derivatives for human clinical use. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Inuloxins A-D and derivatives as antileishmanial agents: structure-activity relationship study

    Science.gov (United States)

    Inuloxins A-D (1-4) and a-costic acid (5), the phytotoxic compounds previously isolated from Inula viscosa, as well as synthetic derivatives of inuloxin A (compounds 6-10), inuloxin C (compound 11) and inuloxin D (compound 12) were tested in vitro for their activity against Leishmania donovani, the ...

  11. Synthesis of Some Benzimidazole Derivatives Bearing 1,3,4-Oxadiazole Moiety as Anticancer Agents.

    Science.gov (United States)

    Mochona, Bereket; Mazzio, Elizabeth; Gangapurum, Madhavei; Mateeva, Nelly; Redda, K K

    2015-04-01

    In an effort to establish new benzimidazole related structural leads with improved anticancer activity, several new benzimidazole derivatives (5a-i) with 1,3,4-oxadiazole scaffold incorporated were synthesized and studied for their anticancer activity. The anticancer screening against MDA-MB-231 breast cancer cell lines showed that compound (5c) exhibited moderate cytotoxicity.

  12. Synthesis and Evaluation of Selected Benzimidazole Derivatives as Potential Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Fatmah A. S. Alasmary

    2015-08-01

    Full Text Available A library of 53 benzimidazole derivatives, with substituents at positions 1, 2 and 5, were synthesized and screened against a series of reference strains of bacteria and fungi of medical relevance. The SAR analyses of the most promising results showed that the antimicrobial activity of the compounds depended on the substituents attached to the bicyclic heterocycle. In particular, some compounds displayed antibacterial activity against two methicillin-resistant Staphylococcus aureus (MRSA strains with minimum inhibitory concentrations (MICs comparable to the widely-used drug ciprofloxacin. The compounds have some common features; three possess 5-halo substituents; two are derivatives of (S-2-ethanaminebenzimidazole; and the others are derivatives of one 2-(chloromethyl-1H-benzo[d]imidazole and (1H-benzo[d]imidazol-2-ylmethanethiol. The results from the antifungal screening were also very interesting: 23 compounds exhibited potent fungicidal activity against the selected fungal strains. They displayed equivalent or greater potency in their MIC values than amphotericin B. The 5-halobenzimidazole derivatives could be considered promising broad-spectrum antimicrobial candidates that deserve further study for potential therapeutic applications.

  13. Synthesis and biological evaluation of nitric oxide-releasing matrine derivatives as anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A series of furoxan-based nitric oxide-releasing matrine derivatives(10a-f) were synthesized.The biological evaluation showed that compounds 10a,10b,10e and 10f had stronger cytotoxic activities than 5-fluorouracil against human hepatoma cells(HepG2) in vitro.

  14. Synthesis of Some Novel Heterocyclic and Schiff Base Derivatives as Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Mohamed E. Azab

    2015-10-01

    Full Text Available Treatment of 2,3-diaryloxirane-2,3-dicarbonitriles 1a–c with different nitrogen nucleophiles, e.g., hydrazine, methyl hydrazine, phenyl hydrazine, hydroxylamine, thiosemicarbazide, and/or 2-amino-5-phenyl-1,3,4-thiadiazole, afforded pyrazole, isoxazole, pyrrolotriazine, imidazolothiadiazole derivatives 2–5, respectively. Reacting pyrazoles 2a–c with aromatic aldehydes and/or methyl glycinate produced Schiff’s bases 7a–d and pyrazolo[3,4-b]-pyrazinone derivative 8, respectively. Treating 7 with ammonium acetate and/or hydrazine hydrate, furnished the imidazolopyrazole and pyrazolotriazine derivatives 9 and 10, respectively. Reaction of 8 with chloroacetic acid and/or diethyl malonate gave tricyclic compound 11 and triketone 12, respectively. On the other hand, compound 1 was reacted with active methylene precursors, e.g., acetylacetone and/or cyclopentanone producing adducts 14a,b which upon fusion with ammonium acetate furnished the 3-pyridone derivatives 15a,b, respectively. Some of newly synthesized compounds were screened for activity against bacterial and fungal strains and most of the newly synthesized compounds showed high antimicrobial activities. The structures of the new compounds were elucidated using IR, 1H-NMR, 13C-NMR and mass spectroscopy.

  15. Novel Schiff-base-derived FabH inhibitors with dioxygenated rings as antibiotic agents.

    Science.gov (United States)

    Zhou, Yang; Du, Qian-Ru; Sun, Jian; Li, Jing-Ran; Fang, Fei; Li, Dong-Dong; Qian, Yong; Gong, Hai-Bin; Zhao, Jing; Zhu, Hai-Liang

    2013-03-01

    Fatty acid biosynthesis plays a vital role in bacterial survival and several key enzymes involved in this biosynthetic pathway have been identified as attractive targets for the development of new antibacterial agents. Of these promising targets, β-ketoacyl-acyl carrier protein (ACP) synthase III (FabH) is the most attractive target that could trigger the initiation of fatty acid biosynthesis and is highly conserved among Gram-positive and -negative bacteria. Designing small molecules with FabH inhibitory activity displays great significance for developing antibiotic agents, which should be highly selective, nontoxic and broad-spectrum. In this manuscript, a series of novel Schiff base compounds were designed and synthesized, and their biological activities were evaluated as potential inhibitors. Among these 21 new compounds, (E)-N-((3,4-dihydro-2H-benzo[b][1,4]dioxepin-7-yl)methylene)hexadecan-1-amine (10) showed the most potent antibacterial activity with a MIC value of 3.89-7.81 μM(-1) against the tested bacterial strains and exhibited the most potent E. coli FabH inhibitory activity with an IC(50) value of 1.6 μM. Docking simulation was performed to position compound 10 into the E. coli FabH active site to determine the probable binding conformation.

  16. An artemisinin derivative of praziquantel as an orally active antischistosomal agent.

    Directory of Open Access Journals (Sweden)

    Lanlan Dong

    Full Text Available Schistosomiasis is a major health problem in tropical and sub-tropical areas caused by species of trematode belonging to the genus Schistosoma. The treatment and control of this disease has been relying on the use of a single drug praziquantel. However, the drug resistance concern urged the development of new drugs against schistosoma. Here, we report our systematic biological evaluation of DW-3-15, a new lead compound developed based on our conjugation design rationale as an effective anti-schistosomal agent.The antischistosomal activity of DW-3-15 was systematically evaluated in S. japonicum infected mouse model for its stage-sensitivity and dose response. The results revealed that DW-3-15 exhibited 60-85% worm reduction rate against different development stage of worm. Scanning electron microscopy (SEM observation indicated that DW-3-15 may damage to the tegument of male schistosomes.Our results demonstrated that DW-3-15 showed potent anti-schistosomal activities in vivo. The results strongly support our conjugation design strategy of artemisinin analogs and further development of DW-3-15 as a new lead compound as anti-schistosomal agent.

  17. Design, synthesis and biological evaluation of novel benzimidazole-2-substituted phenyl or pyridine propyl ketene derivatives as antitumour agents.

    Science.gov (United States)

    Wu, Lin-tao; Jiang, Zhi; Shen, Jia-jia; Yi, Hong; Zhan, Yue-chen; Sha, Ming-quan; Wang, Zhen; Xue, Si-tu; Li, Zhuo-rong

    2016-05-23

    A series of novel benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives were designed and synthesized. The biological activities of these derivatives were then evaluated as potential antitumour agents. These compounds were assayed for growth-inhibitory activity against HCT116, MCF-7 and HepG2 cell lines in vitro. The IC50 values of compounds A1 and A7 against the cancer cells were 0.06-3.64 μM and 0.04-9.80 μM, respectively. Their antiproliferative activities were significantly better than that of 5-Fluorouracil (IC50: 56.96-174.50 μM) and were close to that of Paclitaxel (IC50: 0.026-1.53 μM). The activity of these derivatives was over 100 times more effective than other reported structures of chalcone analogues (licochalcone A). A preliminary mechanistic study suggested that these compounds inhibit p53-MDM2 binding. Compounds A1, A7 and A9 effectively inhibited tumour growth in BALB/c mice with colon carcinoma HCT116 cells. The group administered 200 mg/kg of compound A7 showed a 74.6% tumour growth inhibition with no signs of toxicity at high doses that was similar to the inhibition achieved with the 12.5 mg/kg irinotecan positive control (70.2%). Therefore, this class of benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives represents a promising lead structure for the development of possible p53-MDM2 inhibitors as new antitumour agents.

  18. Synthesis and structure-activity relationship of amidine derivatives of 3,4-ethylenedioxythiophene as novel antibacterial agents.

    Science.gov (United States)

    Stolić, Ivana; Čipčić Paljetak, Hana; Perić, Mihaela; Matijašić, Mario; Stepanić, Višnja; Verbanac, Donatella; Bajić, Miroslav

    2015-01-27

    Current antibacterial chemotherapeutics are facing an alarming increase in bacterial resistance pressuring the search for novel agents that would expand the available therapeutic arsenal against resistant bacterial pathogens. In line with these efforts, a series of 9 amidine derivatives of 3,4-ethylenedioxythiophene were synthesized and, together with 18 previously synthesized analogs, evaluated for their relative DNA binding affinity, in vitro antibacterial activities and preliminary in vitro safety profile. Encouraging antibacterial activity of several subclasses of tested amidine derivatives against Gram-positive (including resistant MRSA, MRSE, VRE strains) and Gram-negative bacterial strains was observed. The bis-phenyl derivatives were the most antibacterially active, while compound 19 from bis-benzimidazole class exhibited the widest spectrum of activity (with MIC of 4, 2, 0.5 and ≤0.25 μg/ml against laboratory strains of Staphyloccocus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Moraxella catarrhalis, respectively and 4-32 μg/ml against clinical isolates of sensitive and resistant S. aureus, Staphylococcus epidermidis and Enterococcus faecium) and also demonstrated the strongest DNA binding affinity (ΔTm of 15.4 °C). Asymmetrically designed compounds and carboxamide-amidines were, in general, less active. Molecular docking indicated that the shape of the 3,4-ethylenedioxythiophene derivatives and their ability to form multiple electrostatic and hydrogen bonds with DNA, corresponds to the binding modes of other minor-groove binders. Herein reported results encourage further investigation of this class of compounds as novel antibacterial DNA binding agents.

  19. Mechanism of sorption sulpho-derivative organic chelating agents on strong base anion exchanger Amberlite IRA-402 by FT-IR/PAS and DRS methods

    Science.gov (United States)

    Wronski, G.; Pasieczna-Patkowska, S.; Hubicki, Z.

    2008-02-01

    In the paper, strong base anion exchanger Amberlite IRA-402 was modified by using sulpho-derivative organic chelating agents as: Brilliant Yellow, Xylenol Orange, Bromophenyl Blue. The investigations exhibited, that anion exchanger Amberlite IRA-402 is modified very simply by organic chelating agents (working capacity 0.25 0.5 g/cm3).

  20. Discovery and Development of Natural Product-derived Chemotherapeutic Agents Based on a Medicinal Chemistry Approach⊥†

    Science.gov (United States)

    Lee, Kuo-Hsiung

    2010-01-01

    Medicinal plants have long been an excellent source of pharmaceutical agents. Accordingly, the long term objectives of the author's research program are to discover and design new chemotherapeutic agents based on plant-derived compound leads by using a medicinal chemistry approach, which is a combination of chemistry and biology. Different examples of promising bioactive natural products and their synthetic analogs, including sesquiterpene lactones, quassinoids, naphthoquinones, phenylquinolones, dithiophenediones, neo-tanshinlactone, tylophorine, suksdorfin, DCK, and DCP, will be presented with respect to their discovery and preclinical development as potential clinical trial candidates. Research approaches include bioactivity- or mechanism of action-directed isolation and characterization of active compounds, rational drug design-based modification and analog synthesis, as well as structure-activity relationship and mechanism of action studies. Current clinical trials agents discovered by the Natural Products Research Laboratories, University of North Carolina, include bevirimat (dimethyl succinyl betulinic acid), which is now in Phase IIb trials for treating AIDS. Bevirimat is also the first in a new class of HIV drug candidates called “maturation inhibitors”. In addition, an etoposide analog, GL-331, progressed to anticancer Phase II clinical trials, and the curcumin analog JC-9 is in Phase II clinical trials for treating acne and in development for trials against prostate cancer. The discovery and development of these clinical trials candidates will also be discussed. PMID:20187635

  1. Design, Synthesis and Biological Evaluation of C(6-Modified Celastrol Derivatives as Potential Antitumor Agents

    Directory of Open Access Journals (Sweden)

    Kaiyong Tang

    2014-07-01

    Full Text Available New six C6-celastrol derivatives were designed, synthesized, and evaluated for their in vitro cytotoxic activities against nine human cancer cell lines (BGC-823, H4, Bel7402, H522, Colo 205, HepG2 and MDA-MB-468. The results showed that most of the compounds displayed potent inhibition against BGC823, H4, and Bel7402, with IC50s of 1.84–0.39 μM. The best compound NST001A was tested in an in vivo antitumor assay on nude mice bearing Colo 205 xenografts, and showed significant inhibition of tumor growth at low concentrations. Therefore, celastrol C-6 derivatives are potential drug candidates for treating cancer.

  2. Chloramphenicol Derivatives as Antibacterial and Anticancer Agents: Historic Problems and Current Solutions

    Directory of Open Access Journals (Sweden)

    George P. Dinos

    2016-06-01

    Full Text Available Chloramphenicol (CAM is the D-threo isomer of a small molecule, consisting of a p-nitrobenzene ring connected to a dichloroacetyl tail through a 2-amino-1,3-propanediol moiety. CAM displays a broad-spectrum bacteriostatic activity by specifically inhibiting the bacterial protein synthesis. In certain but important cases, it also exhibits bactericidal activity, namely against the three most common causes of meningitis, Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis. Resistance to CAM has been frequently reported and ascribed to a variety of mechanisms. However, the most important concerns that limit its clinical utility relate to side effects such as neurotoxicity and hematologic disorders. In this review, we present previous and current efforts to synthesize CAM derivatives with improved pharmacological properties. In addition, we highlight potentially broader roles of these derivatives in investigating the plasticity of the ribosomal catalytic center, the main target of CAM.

  3. Novel Synthetic Monothiourea Aspirin Derivatives Bearing Alkylated Amines as Potential Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Norsyafikah Asyilla Nordin

    2017-01-01

    Full Text Available A new series of aspirin bearing alkylated amines moieties 1–12 were synthesised by reacting isothiocyanate with a series of aniline derivatives in overall yield of 16–56%. The proposed structures of all the synthesised compounds were confirmed using elemental analysis, FTIR, and 1H and  13C NMR spectroscopy. All compounds were evaluated for antibacterial activities against E. coli and S. aureus via turbidimetric kinetic and Kirby Bauer disc diffusion method. Compound 5 bearing meta -CH3 substituent showed the highest relative inhibition zone diameter against tested bacteria compared to ortho and para substituent. Furthermore, aspirin derivatives bearing shorter chains exhibited better bacterial inhibition than longer alkyl chains.

  4. Motuporamine Derivatives as Antimicrobial Agents and Antibiotic Enhancers against Resistant Gram-Negative Bacteria.

    Science.gov (United States)

    Borselli, Diane; Blanchet, Marine; Bolla, Jean-Michel; Muth, Aaron; Skruber, Kristen; Phanstiel, Otto; Brunel, Jean Michel

    2017-02-01

    Dihydromotuporamine C and its derivatives were evaluated for their in vitro antimicrobial activities and antibiotic enhancement properties against Gram-negative bacteria and clinical isolates. The mechanism of action of one of these derivatives, MOTU-N44, was investigated against Enterobacter aerogenes by using fluorescent dyes to evaluate outer-membrane depolarization and permeabilization. Its efficiency correlated with inhibition of dye transport, thus suggesting that these molecules inhibit drug transporters by de-energization of the efflux pump rather than by direct interaction of the molecule with the pump. This suggests that depowering the efflux pump provides another strategy to address antibiotic resistance. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  5. Marinopyrrole derivatives as potential antibiotic agents against methicillin-resistant Staphylococcus aureus (III).

    Science.gov (United States)

    Liu, Yan; Haste, Nina M; Thienphrapa, Wdee; Li, Jerry; Nizet, Victor; Hensler, Mary; Li, Rongshi

    2014-04-30

    The marine natural product, marinopyrrole A (1), was previously shown to have significant antibiotic activity against Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). Although compound (1) exhibits a significant reduction in MRSA activity in the presence of human serum, we have identified key modifications that partially restore activity. We previously reported our discovery of a chloro-derivative of marinopyrrole A (1a) featuring a 2-4 fold improved minimum inhibitory concentration (MIC) against MRSA, significantly less susceptibility to serum inhibition and rapid and concentration-dependent killing of MRSA. Here, we report a novel fluoro-derivative of marinopyrrole A (1e) showing an improved profile of potency, less susceptibility to serum inhibition, as well as rapid and concentration-dependent killing of MRSA.

  6. Bioactivity and structure-activity relationship of cinnamic acid esters and their derivatives as potential antifungal agents for plant protection.

    Science.gov (United States)

    Zhou, Kun; Chen, Dongdong; Li, Bin; Zhang, Bingyu; Miao, Fang; Zhou, Le

    2017-01-01

    A series of cinnamic acid esters and their derivatives were synthesized and evaluated for antifungal activities in vitro against four plant pathogenic fungi by using the mycelium growth rate method. Structure-activity relationship was derived also. Almost all of the compounds showed some inhibition activity on each of the fungi at 0.5 mM. Eight compounds showed the higher average activity with average EC50 values of 17.4-28.6 μg/mL for the fungi than kresoxim-methyl, a commercial fungicide standard, and ten compounds were much more active than commercial fungicide standards carbendazim against P. grisea or kresoxim-methyl against both P. grisea and Valsa mali. Compounds C1 and C2 showed the higher activity with average EC50 values of 17.4 and 18.5 μg/mL and great potential for development of new plant antifungal agents. The structure-activity relationship analysis showed that both the substitution pattern of the phenyl ring and the alkyl group in the alcohol moiety significantly influences the activity. There exists complexly comprehensive effect between the substituents on the phenyl ring and the alkyl group in the alcohol moiety on the activity. Thus, cinnamic acid esters showed great potential the development of new antifungal agents for plant protection due to high activity, natural compounds or natural compound framework, simple structure, easy preparation, low-cost and environmentally friendly.

  7. Design, synthesis and evaluation of novel 4-dimethylamine flavonoid derivatives as potential multi-functional anti-Alzheimer agents.

    Science.gov (United States)

    Luo, Wen; Su, Ya-Bin; Hong, Chen; Tian, Run-Guo; Su, Lei-Peng; Wang, Yue-Qiao; Li, Yang; Yue, Jun-Jie; Wang, Chao-Jie

    2013-12-01

    A series of 4-dimethylamine flavonoid derivatives 5a-5r were designed, synthesized and evaluated as potential multi-functional anti-Alzheimer agents. The results showed that most of the synthesized compounds exhibited high acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity at the micromolar range (IC50, 1.83-33.20 μM for AChE and 0.82-11.45 μM for BChE). A Lineweaver-Burk plot indicated a mixed-type inhibition for compound 5j with AChE, and molecular modeling study showed that 5j targeted both the catalytic active site (CAS) and the peripheral anionic site (PAS) of AChE. Besides, the derivatives showed potent self-induced Aβ aggregation inhibitory activity at 20 μM with percentage from 25% to 48%. In addition, some compounds (5j-5q) showed potent oxygen radical absorbance capacity (ORAC) ranging from 1.5- to 2.6-fold of the Trolox value. These compounds should be further investigated as multi-potent agents for the treatment of Alzheimer's disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Synthesis, Characterization and Biological Evaluation of Some Quinoxaline Derivatives: A Promising and Potent New Class of Antitumor and Antimicrobial Agents.

    Science.gov (United States)

    Al-Marhabi, Aisha R; Abbas, Hebat-Allah S; Ammar, Yousry A

    2015-11-03

    In continuation of our endeavor towards the development of potent and effective anticancer and antimicrobial agents; the present work deals with the synthesis of some novel tetrazolo[1,5-a]quinoxalines, N-pyrazoloquinoxalines, the corresponding Schiff bases, 1,2,4-triazinoquinoxalines and 1,2,4-triazoloquinoxalines. These compounds were synthesized via the reaction of the key intermediate hydrazinoquinoxalines with various reagents and evaluated for anticancer and antimicrobial activity. The results indicated that tetrazolo[1,5-a]quinoxaline derivatives showed the best result, with the highest inhibitory effects towards the three tested tumor cell lines, which were higher than that of the reference doxorubicin and these compounds were non-cytotoxic to normal cells (IC50 values > 100 μg/mL). Also, most of synthesized compounds exhibited the highest degrees of inhibition against the tested strains of Gram positive and negative bacteria, so tetrazolo[1,5-a]quinoxaline derivatives show dual activity as anticancer and antimicrobial agents.

  9. Synthesis, Characterization and Biological Evaluation of Some Quinoxaline Derivatives: A Promising and Potent New Class of Antitumor and Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Aisha R. Al-Marhabi

    2015-11-01

    Full Text Available In continuation of our endeavor towards the development of potent and effective anticancer and antimicrobial agents; the present work deals with the synthesis of some novel tetrazolo[1,5-a]quinoxalines, N-pyrazoloquinoxalines, the corresponding Schiff bases, 1,2,4-triazinoquinoxalines and 1,2,4-triazoloquinoxalines. These compounds were synthesized via the reaction of the key intermediate hydrazinoquinoxalines with various reagents and evaluated for anticancer and antimicrobial activity. The results indicated that tetrazolo[1,5-a]quinoxaline derivatives showed the best result, with the highest inhibitory effects towards the three tested tumor cell lines, which were higher than that of the reference doxorubicin and these compounds were non-cytotoxic to normal cells (IC50 values > 100 μg/mL. Also, most of synthesized compounds exhibited the highest degrees of inhibition against the tested strains of Gram positive and negative bacteria, so tetrazolo[1,5-a]quinoxaline derivatives show dual activity as anticancer and antimicrobial agents.

  10. Bis(imidazolium) salts derived from amino acids as receptors and transport agents for chloride anions

    NARCIS (Netherlands)

    González-Mendoza, Laura; Altava, Belén; Burguete, M.I.; Escorihuela, Jorge; Hernando, Elsa; Luis, S.V.; Quesada, Roberto; Vicent, Cristian

    2015-01-01

    The binding properties of bis(imidazolium) hosts 1a-c derived from amino acids towards different anions have been studied by 1H NMR titration experiments in 95:05 CD3CN:H2O at 303 K, ESI-MS and theoretical calculations. Among this family, the salt 1c showed a stro

  11. Synthesis and biological evaluation of novel imidazolidine derivatives as candidates to schistosomicidal agents

    Science.gov (United States)

    Matos-Rocha, Thiago José; de Lima, Maria do Carmo Alves; da Silva, Anekécia Lauro; de Oliveira, Jamerson Ferreira; Gouveia, Allana Lemos Andrade; da Silva, Vinícius Barros Ribeiro; de Almeida, Antônio Sérgio Alves; Brayner, Fábio André; Cardoso, Pablo Ramon Gualberto; Pitta-Galdino, Marina da Rocha; Pitta, Ivan da Rocha; Rêgo, Moacyr Jesus Barreto de Melo; Alves, Luiz Carlos; Pitta, Maira Galdino da Rocha

    2017-01-01

    ABSTRACT Introduction: Schistosomiasis is an infectious parasitic disease caused by trematodes of the genus Schistosoma, which threatens at least 258 million people worldwide and its control is dependent on a single drug, praziquantel. The aim of this study was to evaluate the anti-Schistosoma mansoni activity in vitro of novel imidazolidine derivatives. Material and methods: We synthesized two novel imidazolidine derivatives: (LPSF/PTS10) (Z)-1-(2-chloro-6-fluorobenzyl)-4-(4-dimethylaminobenzylidene)-5-thioxoimidazolidin-2-one and (LPSF/PTS23) (Z)-1-(2-chloro-6-fluoro-benzyl)-5-thioxo-4-(2,4,6-trimethoxy-benzylidene)-imidazolidin-2-one. The structures of two compounds were determined by spectroscopic methods. During the biological assays, parameters such as motility, oviposition, mortality and analysis by Scanning Electron Microscopy were performed. Results: LPSF/PTS10 and LPSF/PTS23 were considered to be active in the separation of coupled pairs, mortality and to decrease the motor activity. In addition, LPSF/PTS23 induced ultrastructural alterations in worms, after 24 h of contact, causing extensive erosion over the entire body of the worms. Conclusion: The imidazolidine derivatives containing the trimetoxy and benzylidene halogens showed promising in vitro schistosomicidal activity. PMID:28380119

  12. Computational Studies of Benzoxazinone Derivatives as Antiviral Agents against Herpes Virus Type 1 Protease

    Directory of Open Access Journals (Sweden)

    Juliana F. R. Mello

    2015-06-01

    Full Text Available Herpes simplex virus infections have been described in the medical literature for centuries, yet the the drugs available nowadays for therapy are largely ineffective and low oral bioavailability plays an important role on the inefficacy of the treatments. Additionally, the details of the inhibition of Herpes Virus type 1 are still not fully understood. Studies have shown that several viruses encode one or more proteases required for the production new infectious virions. This study presents an analysis of the interactions between HSV-1 protease and benzoxazinone derivatives through a combination of structure-activity relationships, comparative modeling and molecular docking studies. The structure activity relationship results showed an important contribution of hydrophobic and polarizable groups and limitations for bulky groups in specific positions. Two Herpes Virus type 1 protease models were constructed and compared to achieve the best model which was obtained by MODELLER. Molecular docking results pointed to an important interaction between the most potent benzoxazinone derivative and Ser129, consistent with previous mechanistic data. Moreover, we also observed hydrophobic interactions that may play an important role in the stabilization of inhibitors in the active site. Finally, we performed druglikeness and drugscore studies of the most potent derivatives and the drugs currently used against Herpes virus.

  13. DNA binding properties and biological evaluation of dihydropyrimidinones derivatives as potential antitumor agents

    Science.gov (United States)

    Wang, Gongke; Li, Xiangrong; Gou, Yaping; Chen, Yuhan; Yan, Changling; Lu, Yan

    2013-10-01

    The binding properties of two medicinally important dihydropyrimidinones derivatives 5-(Ethoxycarbonyl)-6-methyl-4-phenyl-3,4-dihydropyrimidin-2(1H)-one (EMPD) and 5-(Ethoxycarbonyl)-6-methyl-4-(4-chlorophenyl)-3,4-dihydropyrimidin-2(1H)-one (EMCD) with calf-thymus DNA (ctDNA) were investigated by spectroscopy, viscosity, isothermal titration calorimetry (ITC) and molecular modeling techniques. Simultaneously, their biological activities were evaluated with MTT assay method. The binding constants determined with spectroscopic titration and ITC were found to be in the same order of 104 M-1. According to the results of viscosity studies, fluorescence competitive binding experiment and ITC investigations, intercalative binding was evaluated as the dominant binding modes between the two compounds and ctDNA. Furthermore, the results of molecular modeling corroborated those obtained from spectroscopic, viscosimetric and ITC investigations. Evaluation of the antitumor activities of the two derivatives against different tumor cell lines proved that they exhibited significant tumor cell inhibition rate, accordingly blocking DNA transcription and replication. The present results favor the development of potential drugs related with dihydropyrimidinones derivatives in the treatment of some diseases.

  14. New α-Methylene-γ-Butyrolactone Derivatives as Potential Fungicidal Agents: Design, Synthesis and Antifungal Activities

    Directory of Open Access Journals (Sweden)

    Yongling Wu

    2016-01-01

    Full Text Available In consideration of the fact that the α-methylene-γ-butyrolactone moiety is a major bio-functional group in the structure of carabrone and possesses some agricultural biological activity, forty-six new ester and six new ether derivatives containing α-methylene-γ-butyrolactone moieties were synthesized, and their fungicidal activities against Colletotrichum lagenarium and Botrytis cinerea were investigated. Most of the synthesized compounds showed moderate to significant fungicidal activity. Among them, halogen atom-containing derivatives showed better activity than others, especially compounds 6a,d which exhibited excellent fungicidal activity against C. lagenarium, with IC50 values of 7.68 and 8.17 μM. The structure-activity relationship (SAR analysis indicated that ester derivatives with electron-withdrawing groups on the benzene ring showed better fungicidal activity than those with electron-donating groups. A quantitative structure-activity relationship (QSAR model (R2 = 0.9824, F = 203.01, S2 = 0.0083 was obtained through the heuristic method. The built model revealed a strong correlation of fungicidal activity against C. lagenarium with the molecular structures of these compounds. These results are expected to prove helpful in the design and exploration of low toxicity and high efficiency α-methylene-γ-butyrolactone-based fungicides.

  15. Recent Advances in the Development of Antineoplastic Agents Derived from Natural Products.

    Science.gov (United States)

    Trendowski, Matthew

    2015-11-01

    Through years of evolutionary selection pressures, organisms have developed potent toxins that coincidentally have marked antineoplastic activity. These natural products have been vital for the development of multiagent treatment regimens currently employed in cancer chemotherapy, and are used in the treatment of a variety of malignancies. Therefore, this review catalogs recent advances in natural product-based drug discovery via the examination of mechanisms of action and available clinical data to highlight the utility of these novel compounds in the burgeoning age of precision medicine. The review also highlights the recent development of antibody-drug conjugates and other immunotoxins, which are capable of delivering highly cytotoxic agents previously deemed too toxic to elicit therapeutic benefit preferentially to neoplastic cells. Finally, the review examines natural products not currently used in the clinic that have novel mechanisms of action, and may serve to supplement current chemotherapeutic protocols.

  16. Perspectives of Benzimidazole Derivatives as Anticancer Agents in the New Era.

    Science.gov (United States)

    Yadav, Snehlata; Narasimhan, Balasubramanian; Kaur, Harmeet

    2016-01-01

    Cancer is one of the deadliest diseases nowadays and is a great topic for research as the challenging task is to develop new entities with selectivity towards cancerous cells. Heterocyclic compounds are of great importance in medicinal chemistry as they possess an extensive range of therapeutic applications. Benzimidazole is one such important heterocyclic organic compound having structural analogy to nucleotides found in human body and hence is an important pharmacophore in medicinal chemistry. A variety of marketed drugs containing benzimidazole are thiabendazole, flubendazole (anthelmintic), astmizole (antihistaminic), lansoprazole and omeprazole (antiulcerative). In the light of the above facts, this review is an attempt to summarize the collective contributions from the authors around the world in the field of anticancer agents. This review highlights synthetic schemes and anticancer activity results of the research done in the past years.

  17. Theophylline-7-acetic acid derivatives with amino acids as anti-tuberculosis agents.

    Science.gov (United States)

    Voynikov, Yulian; Valcheva, Violeta; Momekov, Georgi; Peikov, Plamen; Stavrakov, Georgi

    2014-07-15

    A series of amides were synthesized by condensation of theophylline-7-acetic acid and eight commercially available amino acid methyl ester hydrochlorides. Consecutive hydrolysis of six of the amido-esters resulted in the formation of corresponding amido-acids. The newly synthesized compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis H37Rv. The activity varied depending on the amino acid fragments and in seven cases exerted excellent values with MICs 0.46-0.26 μM. Assessment of the cytotoxicity revealed that the compounds were not cytotoxic against the human embryonal kidney cell line HEK-293T. The theophylline-7-acetamides containing amino acid moieties appear to be promising lead compounds for the development of antimycobacterial agents.

  18. Plant-derived antimalarial agents: new leads and efficient phythomedicines. Part I. Alkaloids

    OpenAIRE

    Oliveira,Alaíde B. de; Maria Fâni Dolabela; Fernão C. Braga; Rose L.R.P. Jácome; Varotti,Fernando P.; Marinete M Póvoa

    2009-01-01

    A malária ainda é um dos mais sérios problemas de saúde pública e a principal causa de mortalidade e morbidade nas regiões endêmicas. O Brasil está entre os 30 países com maior incidência de malária e a maior parte dos casos ocorre na Amazônia Legal. Novos agentes terapêuticos são necessários para o tratamento da malária. Muitas espécies vegetais são utilizadas na medicina tradicional de vários países endêmicos mas é relativamente reduzido o número daquelas que já foram investigadas quanto à ...

  19. Effect of chitosan and its derivatives as antifungal and preservative agents on postharvest green asparagus.

    Science.gov (United States)

    Qiu, Miao; Wu, Chu; Ren, Gerui; Liang, Xinle; Wang, Xiangyang; Huang, Jianying

    2014-07-15

    The antifungal activity and effect of high-molecular weight chitosan (H-chitosan), low-molecular weight chitosan (L-chitosan) and carboxymethyl chitosan (C-chitosan) coatings on postharvest green asparagus were evaluated. L-chitosan and H-chitosan efficiently inhibited the radial growth of Fusarium concentricum separated from postharvest green asparagus at 4 mg/ml, which appeared to be more effective in inhibiting spore germination and germ tube elongation than that of C-chitosan. Notably, spore germination was totally inhibited by L-chitosan and H-chitosan at 0.05 mg/ml. Coated asparagus did not show any apparent sign of phytotoxicity and maintained good quality over 28 days of cold storage, according to the weight loss and general quality aspects. Present results inferred that chitosan could act as an attractive preservative agent for postharvest green asparagus owing to its antifungal activity and its ability to stimulate some defense responses during storage.

  20. Synthesis and in vitro Evaluation of New Benzothiazole Derivatives as Schistosomicidal Agents

    Directory of Open Access Journals (Sweden)

    Mona A Mahran

    2007-03-01

    Full Text Available A series of benzothiazol-2-yl-dithiocarbamates 3a-d along with their copper complexes 4a-c were synthesized via the reaction of suitable alkyl, aralkyl or heteroaryl halides with the sodium salt of benzothiazol-2-yl-dithiocarbamic acid, followed by complexation with copper sulphate. N-(4-Acetyl-5-aryl-4,5-dihydro-1,3,4-thiadiazol-2-yl-N-benzothiazol-2-yl-acetamides 7a-c were synthesized by cyclization of the appropriate thiosemicarbazones 6a-c in acetic anhydride. Selected compounds were screened for in vitro schistosomicidal activity against Schistosoma mansoni at three different dosage levels (10, 50 and 100 μg/ mL. Three of these products, 4a-c, showed schistosomicidal activity similar to praziquantel, with 100% worm mortality at 10 μg/mL. These compounds would constitute a new class of potent schistosomicidal agents.

  1. Semantic prioritization of novel causative genomic variants

    KAUST Repository

    Boudellioua, Imane

    2017-04-17

    Discriminating the causative disease variant(s) for individuals with inherited or de novo mutations presents one of the main challenges faced by the clinical genetics community today. Computational approaches for variant prioritization include machine learning methods utilizing a large number of features, including molecular information, interaction networks, or phenotypes. Here, we demonstrate the PhenomeNET Variant Predictor (PVP) system that exploits semantic technologies and automated reasoning over genotype-phenotype relations to filter and prioritize variants in whole exome and whole genome sequencing datasets. We demonstrate the performance of PVP in identifying causative variants on a large number of synthetic whole exome and whole genome sequences, covering a wide range of diseases and syndromes. In a retrospective study, we further illustrate the application of PVP for the interpretation of whole exome sequencing data in patients suffering from congenital hypothyroidism. We find that PVP accurately identifies causative variants in whole exome and whole genome sequencing datasets and provides a powerful resource for the discovery of causal variants.

  2. Synthesis and Biological Evaluation of Apigenin Derivatives as Antibacterial and Antiproliferative Agents

    Directory of Open Access Journals (Sweden)

    Jinyi Wang

    2013-09-01

    Full Text Available Two series of apigenin [5,7-dihydroxy-2-(4-hydroxyphenyl-4H-chromen-4-one] derivatives, 3a–3j and 4a–4j, were synthesized. The apigenin and alkyl amines moieties of these compounds were separated by C2 or C3 spacers, respectively. The chemical structures of the apigenin derivatives were confirmed using 1H-NMR, 13C-NMR, and electrospray ionization mass spectroscopy. The in vitro antibacterial and antiproliferative activities of all synthesized compounds were determined. Among the tested compounds, 4a–4j displayed significant antibacterial activity against the tested strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. Additionally, 4i showed the best inhibitory activity with minimum inhibitory concentrations of 1.95, 3.91, 3.91, and 3.91 μg/mL against S. aureus, B. subtilis, E. coli, and P. aeruginosa, respectively. The antiproliferative activity of the apigenin derivatives was evaluated by an MTT [3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide] assay. We determined that 4a–4j displayed better growth inhibition activity against four human cancer cell lines, namely, human lung (A549, human cervical (HeLa, human hepatocellular liver (HepG2, and human breast (MCF-7 cancer cells, than the parent apigenin. Compound 4j was found to be the most active antiproliferative compound against the selected cancer cells. Structure-activity relationships were also discussed based on the obtained experimental data.

  3. The synthesis and biological evaluation of multifunctionalised derivatives of noscapine as cytotoxic agents.

    Science.gov (United States)

    Debono, Aaron J; Mistry, Sarah J; Xie, Jinhan; Muthiah, Divya; Phillips, Jackson; Ventura, Sabatino; Callaghan, Richard; Pouton, Colin W; Capuano, Ben; Scammells, Peter J

    2014-02-01

    Noscapine, a phthalideisoquinoline alkaloid derived from Papaver somniferum, is a well-known antitussive drug that has a relatively safe in vitro toxicity profile. Noscapine is also known to possess weak anticancer efficacy, and since its discovery, efforts have been made to design derivatives with improved potency. Herein, the synthesis of a series of noscapine analogues, which have been modified in the 6', 9', 1 and 7-positions, is described. In a previous study, replacement of the naturally occurring N-methyl group in the 6'-position with an N-ethylaminocarbonyl was shown to promote cell-cycle arrest and cytotoxicity against three cancer cell lines. Here, this modification has been combined with other structural changes that have previously been shown to improve anticancer activity, namely halo substitution in the 9'-position, regioselective O-demethylation to reveal a free phenol in the 7-position, and reduction of the lactone to the corresponding cyclic ether in the 1-position. The incorporation of new aryl substituents in the 9'-position was also investigated. The study identified interesting new compounds able to induce G2/M cell-cycle arrest and that possess cytotoxic activity against the human prostate carcinoma cell line PC3, the human breast adenocarcinoma cell line MCF-7, and the human pancreatic epithelioid carcinoma cell line PANC-1. In particular, the ethyl urea cyclic ether noscapinoids and a compound containing a 6'-ethylaminocarbonyl along with 9'-chloro, 7-hydroxy and lactone moieties exhibited the most promising biological activities, with EC50 values in the low micromolar range against all three cancer cell lines, and these derivatives warrant further investigation.

  4. THE PHARMACOLOGY OF NEW ADRENERGIC NEURONE BLOCKING AGENTS, N-P-CYCLOHEXYLBENZYLTROPINIUM DERIVATIVES.

    Science.gov (United States)

    DODA, M; FEHER, O; GYOERGY, L; NADOR, K

    1963-08-01

    The three N-p-cyclohexylbenzyltropinium derivatives studied gave rise to lasting hypotension after transient stimulation and block of sympathetic ganglia in anaesthetized and conscious animals. The drugs inhibited the contractions of the nictitating membrane and spleen evoked by pre- or postganglionic nerve stimulation. In adrenalectomized animals the pressor effect of tetramethylammonium, the hypertensive response to carotid arterial occlusion and the effect of tyramine on the nictitating membrane were also reduced. The drugs have slight or no parasympathomimetic, parasympatholytic or curare-like side-effects. The bretylium-like action of the compounds is discussed.

  5. Anthracenedione Derivatives as Anticancer Agents Isolated from Secondary Metabolites of the Mangrove Endophytic Fungi

    OpenAIRE

    Jian-ye Zhang; Li-yang Tao; Yong-ju Liang; Li-ming Chen; Yan-jun Mi; Li-sheng Zheng; Fang Wang; Zhi-gang She; Yong-cheng Lin; Kenneth Kin Wah To; Li-wu Fu

    2010-01-01

    In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403) and Guignardia sp. (No. 4382). Some of them inhibited potently the growth of KB and KBv200 cells, among which compound 6 displayed strong cytotoxicity with IC50 values of 3.17 and 3.21 μM to KB and KBv200 cells, respectively. Furthermore, we demonstrate that the mechanism involved in the apoptosis induced by co...

  6. Anthracenedione derivatives as anticancer agents isolated from secondary metabolites of the mangrove endophytic fungi.

    Science.gov (United States)

    Zhang, Jian-ye; Tao, Li-yang; Liang, Yong-ju; Chen, Li-ming; Mi, Yan-jun; Zheng, Li-sheng; Wang, Fang; She, Zhi-gang; Lin, Yong-cheng; To, Kenneth Kin Wah; Fu, Li-wu

    2010-04-23

    In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403) and Guignardia sp. (No. 4382). Some of them inhibited potently the growth of KB and KBv200 cells, among which compound 6 displayed strong cytotoxicity with IC(50) values of 3.17 and 3.21 microM to KB and KBv200 cells, respectively. Furthermore, we demonstrate that the mechanism involved in the apoptosis induced by compound 6 is probably related to mitochondrial dysfunction. Additionally, the structure-activity relationships of these compounds are discussed.

  7. Anthracenedione Derivatives as Anticancer Agents Isolated from Secondary Metabolites of the Mangrove Endophytic Fungi

    Directory of Open Access Journals (Sweden)

    Jian-ye Zhang

    2010-04-01

    Full Text Available In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403 and Guignardia sp. (No. 4382. Some of them inhibited potently the growth of KB and KBv200 cells, among which compound 6 displayed strong cytotoxicity with IC50 values of 3.17 and 3.21 μM to KB and KBv200 cells, respectively. Furthermore, we demonstrate that the mechanism involved in the apoptosis induced by compound 6 is probably related to mitochondrial dysfunction. Additionally, the structure-activity relationships of these compounds are discussed.

  8. Synthesis and in vivo evaluation of 11-substituted estradiol derivatives as anti-implantation agents.

    Science.gov (United States)

    Dwivedy, Indra; Gupta, Atul; Grover, Arvinder; Srivastava, Vandana; Singh, Man Mohan; Ray, Suprabhat

    2008-07-15

    Synthesis of 11-substituted estradiol derivatives (12-17) has been carried out by the Grignard reaction with alkyl, allyl, and benzyl halides on 17beta-hydroxy-3-methoxy-11-oxo-estra-1,3,5(10),8(9)-tetraene (10). The novel compounds (10 and 12-17) were evaluated for their preliminary post-coital contraceptive (anti-implantation) activity in Sprague-Dawley rats. The tested compounds were administered orally and showed significant anti-implantation activity. Compound 13 is the most potent compound in the series which showed 100% contraceptive efficacy at 1.25 mg kg(-1).

  9. Design and Synthesis of Pyrazole-3-one Derivatives as Hypoglycaemic Agents

    Directory of Open Access Journals (Sweden)

    Prasanna A. Datar

    2015-01-01

    Full Text Available Pyrazole-3-one compounds were designed on the basis of docking studies of previously reported antidiabetic pyrazole compounds. The amino acid residues found during docking studies were used as guidelines for the modification of aromatic substitutions on pyrazole-3-one structure. Depending on the docking score, the designed compounds were selectively prioritized for synthesis. The synthesized compounds were subjected to in vivo hypoglycemic activity using alloxan induced diabetic rats and metformin as a standard. Compound 4 having sulphonamide derivative was found to be the most potent compound among the series.

  10. SYNTHESIS AND CHARACTERIZATION OF SOME PYRAZOLINE DERIVATIVES OF AZAINDOLIZINE ANALOGUE AS ANTIMICROBIAL AGENT

    Directory of Open Access Journals (Sweden)

    N.N. Kansagara

    2015-01-01

    Full Text Available Different pyrazoline derivatives were synthesized by cyclization of substituted chalcones with phenyl hydrazine in basic conditions. Some new 1-Aryl-3-[6-methyl-2-(4-methylphenyl imidazo [1,2-a] pyridin-3- yl]prop-2-ene-1-ones (1a-l and 3-(3-Aryl-1-phenyl-4,5-dihydro-1H-pyrazol-5-yl-6-methyl-2-(4- methylphenylimidazo[1,2-a]pyridines (2a-l were prepared. All the prepared compounds were characterized by their spectral (I.R., N.M.R., Mass data and screened for their antimicrobial activities.

  11. Derivatives of aryl-4-guanidinomethylbenzoate and N-aryl-4-guanidinomethylbenzamide as new antibacterial agents: synthesis and bioactivity

    Institute of Scientific and Technical Information of China (English)

    Wen-yuan YU; Li-xia YANG; Jian-shu XIE; Ling ZHOU; Xue-yuan JIANG; De-xu ZHU; Mutsumi MURAMATSU; Ming-wei WANG

    2008-01-01

    Aim: The aim of the present study was to design, synthesize, and evaluate novel antibacterial agents, derivatives of aryl-4-guanidinomethylbenzoate and N-aryl-4-guanidinomethylbenzamide. Methods: A total of 44 derivatives of aryl-4-guanidin-omethylbenzoate (series A) and N-aryl-4-guanidinomethylbenzamide (series B) were synthesized and their antibacterial activities were assessed in vitro against a variety of Gram-positive and Gram-negative bacteria by an agar dilution method. Results: Twelve compounds showed potent bactericidal effects against a panel of Gram-positive germs, including methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), vancomycin-intermediate Sta-phylococcus aureus (VISA), and methicillin-resistant coagulase-negative staphy-lococci (MRCNS), with minimum inhibitory concentrations (MIC) ranging be-tween 0.5 and 8 μg/mL, which were comparable to the MIC values of several marketed antibiotics. They exhibited weak or no activity on the Gram-negative bacteria tested. In addition, these compounds displayed high inhibitory activities towards oligopeptidase B of bacterial origin. Conclusion: In comparison with the previ-ously reported MIC values of several known antibiotics, the derivatives of aryl-4-guanidinomethylbenzoate and N-aryl-4-guanidinomethylbenzamide showed com-parable in vitro bactericidal activities against VRE and VISA as linezolid. Their growth inhibitory effects on MRSA were similar to vancomycin, but were less potent than linezolid and vancomycin against MRCNS. This class of compounds may have the potential to be developed into narrow spectrum antibacterial agents against certain drug-resistant strains of bacteria.

  12. Novel coumarin-benzimidazole derivatives as antioxidants and safer anti-inflammatory agents.

    Science.gov (United States)

    Arora, Radha Krishan; Kaur, Navneet; Bansal, Yogita; Bansal, Gulshan

    2014-10-01

    Inspired from occurrence of anti-inflammatory activity of 3-substituted coumarins and antiulcer activity of various 2-substituted benzimidazoles, novel compounds have been designed by coupling coumarin derivatives at 3-position directly or through amide linkage with benzimidazole nucleus at 2-position. The resultant compounds are expected to exhibit both anti-inflammatory and antioxidant activities along with less gastric toxicity profile. Two series of coumarin-benzimidazole derivatives (4a-e and 5a-e) were synthesized and evaluated for anti-inflammatory activity and antioxidant activity. Compounds 4c, 4d and 5a displayed good anti-inflammatory (45.45%, 46.75% and 42.85% inhibition, respectively, versus 54.54% inhibition by indomethacin) and antioxidant (IC50 of 19.7, 13.9 and 1.2 µmol/L, respectively, versus 23.4 µmol/L for butylatedhydroxytoluene) activities. Evaluation of ulcer index and in vivo biochemical estimations for oxidative stress revealed that compounds 4d and 5a remain safe on gastric mucosa and did not induce oxidative stress in tissues. Calculation of various molecular properties suggests the compounds to be sufficiently bioavailable.

  13. Resveratrol-salicylate derivatives as selective DNMT3 inhibitors and anticancer agents.

    Science.gov (United States)

    Aldawsari, Fahad S; Aguayo-Ortiz, Rodrigo; Kapilashrami, Kanishk; Yoo, Jakyung; Luo, Minkui; Medina-Franco, José L; Velázquez-Martínez, Carlos A

    2016-10-01

    Resveratrol is a natural polyphenol with plethora of biological activities. Resveratrol has previously shown to decrease DNA-methyltransferase (DNMT) enzymes expression and to reactivate silenced tumor suppressor genes. Currently, it seems that no resveratrol analogs have been developed as DNMT inhibitors. Recently, we reported the synthesis of resveratrol-salicylate derivatives and by examining the chemical structure of these analogs, we proposed that these compounds could exhibit DNMT inhibition especially that they resembled NSC 14778, a compound we previously identified as a DNMT inhibitor by virtual screening. Indeed, using in vitro DNMT inhibition assay, some of the resveratrol-salicylate analogs we screened in this work that showed selective inhibition against DNMT3 enzymes which were greater than resveratrol. A molecular docking study revealed key binding interactions with DNMT3A and DNMT3B enzymes. In addition, the most active analog, 10 showed considerable cytotoxicity against three human cancer cells; HT-29, HepG2 and SK-BR-3, which was greater than resveratrol. Further studies are needed to understand the anticancer mechanisms of these derivatives.

  14. Progress Toward the Development of Noscapine and Derivatives as Anticancer Agents.

    Science.gov (United States)

    DeBono, Aaron; Capuano, Ben; Scammells, Peter J

    2015-08-13

    Many nitrogen-moiety containing alkaloids derived from plant origins are bioactive and play a significant role in human health and emerging medicine. Noscapine, a phthalideisoquinoline alkaloid derived from Papaver somniferum, has been used as a cough suppressant since the mid 1950s, illustrating a good safety profile. Noscapine has since been discovered to arrest cells at mitosis, albeit with moderately weak activity. Immunofluorescence staining of microtubules after 24 h of noscapine exposure at 20 μM elucidated chromosomal abnormalities and the inability of chromosomes to complete congression to the equatorial plane for proper mitotic separation ( Proc. Natl. Acad. Sci. U. S. A. 1998 , 95 , 1601 - 1606 ). A number of noscapine analogues possessing various modifications have been described within the literature and have shown significantly improved antiprolific profiles for a large variety of cancer cell lines. Several semisynthetic antimitotic alkaloids are emerging as possible candidates as novel anticancer therapies. This perspective discusses the advancing understanding of noscapine and related analogues in the fight against malignant disease.

  15. Phthalocyanine derivatives possessing 2-(morpholin-4-yl)ethoxy groups as potential agents for photodynamic therapy.

    Science.gov (United States)

    Kucinska, Malgorzata; Skupin-Mrugalska, Paulina; Szczolko, Wojciech; Sobotta, Lukasz; Sciepura, Mateusz; Tykarska, Ewa; Wierzchowski, Marcin; Teubert, Anna; Fedoruk-Wyszomirska, Agnieszka; Wyszko, Eliza; Gdaniec, Maria; Kaczmarek, Mariusz; Goslinski, Tomasz; Mielcarek, Jadwiga; Murias, Marek

    2015-03-12

    Three 2-(morpholin-4-yl)ethoxy substituted phthalocyanines were synthesized and characterized. Phthalocyanine derivatives revealed moderate to high quantum yields of singlet oxygen production depending on the solvent applied (e.g., in DMF ranging from 0.25 to 0.53). Their photosensitizing potential for photodynamic therapy was investigated in an in vitro model using cancer cell lines. Biological test results were found particularly encouraging for the zinc(II) phthalocyanine derivative possessing two 2-(morpholin-4-yl)ethoxy substituents in nonperipheral positions. Cells irradiated for 20 min at 2 mW/cm(2) revealed the lowest IC50 value at 0.25 μM for prostate cell line (PC3), whereas 1.47 μM was observed for human malignant melanoma (A375) cells. The cytotoxic activity in nonirradiated cells of novel phthalocyanine was found to be very low. Moreover, the cellular uptake, localization, cell cycle, apoptosis through an ELISA assay, and immunochemistry method were investigated in LNCaP cells. Our results showed that the tested photosensitizer possesses very interesting biological activity, depending on experimental conditions.

  16. Amino Acid Derivatives of Ligustrazine-Oleanolic Acid as New Cytotoxic Agents

    Directory of Open Access Journals (Sweden)

    Fuhao Chu

    2014-11-01

    Full Text Available A series of novel ligustrazine-oleanolic acid (TOA derivatives were designed, and synthesized by conjugating amino acids to the 3-hydroxy group of TOA by ester bonds. Their cytotoxicity was evaluated on four cancer cell lines (HepG2, HT-29, Hela and BGC-823 by standard MTT assays. The ClogP values were calculated by means of computer simulation, and logP values of both 3β-glycine ester olean-12-en-28-oic acid-3,5,6-trimethylpyrazin-2-methyl ester (6a and TOA were determined using a shake flask-ultraviolet spectrophotometry method. It was found that 6a and the 3β-L-lysine ester-6g not only displayed good cytotoxicity (IC50 < 3.5 μM but also possessed better hydrophilicity than TOA. Moreover, 6a (IC50 = 4.884 μM had lower nephrotoxicity than both 6g (IC50 = 2.310 μM and cisplatin (CDDP, IC50 = 3.691 μM on MDCK cells. Combining Giemsa and DAPI staining, it was further verified that 6a could induce HepG2 apoptosis via nuclei fragmentation and had lower nephrotoxicity. In addition, the structure-activity relationships of these derivatives are briefly discussed.

  17. Mathematical modeling of tetrahydroimidazole benzodiazepine-1-one derivatives as an anti HIV agent

    Science.gov (United States)

    Ojha, Lokendra Kumar

    2017-07-01

    The goal of the present work is the study of drug receptor interaction via QSAR (Quantitative Structure-Activity Relationship) analysis for 89 set of TIBO (Tetrahydroimidazole Benzodiazepine-1-one) derivatives. MLR (Multiple Linear Regression) method is utilized to generate predictive models of quantitative structure-activity relationships between a set of molecular descriptors and biological activity (IC50). The best QSAR model was selected having a correlation coefficient (r) of 0.9299 and Standard Error of Estimation (SEE) of 0.5022, Fisher Ratio (F) of 159.822 and Quality factor (Q) of 1.852. This model is statistically significant and strongly favours the substitution of sulphur atom, IS i.e. indicator parameter for -Z position of the TIBO derivatives. Two other parameter logP (octanol-water partition coefficient) and SAG (Surface Area Grid) also played a vital role in the generation of best QSAR model. All three descriptor shows very good stability towards data variation in leave-one-out (LOO).

  18. USE OF WOOD DERIVATIVES AS DOPING / DISPERSING AGENTS IN THE PREPARATION OF POLYPYRROLE AQUEOUS DISPERSIONS

    Directory of Open Access Journals (Sweden)

    Claudia Sasso

    2008-11-01

    Full Text Available Polystyrene sulfonic acid (PSS, lignosulfonic acid (LS sodium salts, and carboxymethylcellulose (CMC were used as doping/dispersing agents in the chemical polymerization of polypyrrole (Ppy. Conductivity measure-ments performed on dry Ppy pellets showed a sharp increase in conductivity when adding the anionic polymers to the polymerization liquor. For a polyanion/pyrrole weight ratio ranging between 0.1 and 0.6, the highest conductivity was given by PpyCMC (82 S/m and PpyPSS (80 S/m, followed by PpyLS (6 S/m. On the other hand, for a polyanion/pyrrole ratio higher than 0.6, the conductivity of PpyPSS systems sharply decreased, and for polyanion/pyrrole ratios higher than 1, the highest conductivity was given by PpyCMC (~10 S/m, followed by PpyLS (~7 S/m and PpyPSS (~5 S/m. Zeta-potential measurements showed that the surface charge of Ppy was strongly affected by the polyanion type and amount. Cationic Ppy particles were obtained in the presence of the two polymers bearing strongly acidic moieties (PSS and LS. Anionic PpyPSS colloids were obtained at the highest PSS/Py ratio, after the degradation of the conducting properties. When using a weakly acidic dopant (CMC, PpyCMC colloids had a negative charge for all of the tested conditions.

  19. Synthesis of hydroxycinnamic acid derivatives as mitochondria-targeted antioxidants and cytotoxic agents

    Directory of Open Access Journals (Sweden)

    Jiyu Li

    2017-01-01

    Full Text Available In order to develop agents with superior chemopreventive and chemotherapeutic properties against hepatocellular carcinomas, mitochondria-targeted hydroxycinnamic acids (MitoHCAs were synthesized by conjugation with a triphenylphosphonium cation. These synthetic compounds were evaluated for their antioxidant activities in hepatic mitochondria, including against OH∙− and ROO∙− induced lipid peroxidation. H2O2 production was decreased significantly by increasing glutathione peroxidase and catalase activities. In addition, cell proliferation data from three cell lines (HepG2, L02 and WI38 indicated that the MitoHCAs were selective for cancer cells. Interestingly, the MitoHCAs both with or without Ca2+ triggered mitochondrial dysfunction by inducing mitochondrial swelling, collapsing the mitochondrial membrane potential and causing cytochrome c release. In particular, an inhibitor of the mitochondrial permeability transition pore (mPTP, cyclosporin A, attenuated mitochondrial damage and cell apoptosis, indicating that mPTP may be involved in the antiproliferative activity of MitoHCAs. Further studies focused on structural optimization of these compounds are onging.

  20. Phthalimide-derived strigolactone mimics as germinating agents for seeds of parasitic weeds.

    Science.gov (United States)

    Cala, Antonio; Ghooray, Kala; Fernández-Aparicio, Mónica; Molinillo, José Mg; Galindo, Juan Cg; Rubiales, Diego; Macías, Francisco A

    2016-11-01

    Broomrapes attack important crops, cause severe yield losses and are difficult to eliminate because their seed bank is virtually indestructible. In the absence of a host, the induction of seed germination leads to inevitable death due to nutrient starvation. Synthetic analogues of germination-inducing factors may constitute a cheap and feasible strategy to control the seed bank. These compounds should be easy and cheap to synthesise, as this will allow their mass production. The aim of this work is to obtain new synthethic germinating agents. Nineteen N-substituted phthalimides containing a butenolide ring and different substituents in the aromatic ring were synthesised. The synthesis started with commercially available phthalimides. The complete collection was assayed against the parasitic weeds Orobanche minor, O. cumana, Phelipanche ramosa and P. aegyptiaca, with the synthetic strigolactone analogue GR24 used as a positive control. These compounds offered low EC50 values: O. cumana 38.3 μM, O. minor 3.77 μM, P. aegyptiaca 1.35 μM and P. ramosa 1.49 μM. The synthesis was carried out in a few steps and provided the target compounds in good yields. The compounds tested showed great selectivity, and low EC50 values were obtained for structures that were simpler than GR24. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. Synthesis, Cytotoxicity, DNA Binding and Apoptosis of Rhein-Phosphonate Derivatives as Antitumor Agents

    Directory of Open Access Journals (Sweden)

    Man-Yi Ye

    2013-04-01

    Full Text Available Several rhein-phosphonate derivatives (5a–c were synthesized and evaluated for in vitro cytotoxicity against HepG-2, CNE, Spca-2, Hela and Hct-116 cell lines. Some compounds showed relatively high cytotoxicity. Especially compounds 5b exhibited the strongest cytotoxicity against HepG-2 and Spca-2 cells (IC50 was 8.82 and 9.01 µM, respectively. All the synthesized compounds exhibited low cytotoxicity against HUVEC cells. Further experiments proved that 5b could disturb the cell cycle in HepG-2 cells and induce apoptosis. In addition, the binding properties of a model conjugate 5b to DNA were investigated by methods (UV-Vis, fluorescence, CD spectroscopy. Results indicated that 5b showed moderate ability to interact ct-DNA.

  2. Synthesis and evaluation of radiolabeled piperazine derivatives of vesamicol as SPECT agents for cholinergic neurons

    Energy Technology Data Exchange (ETDEWEB)

    Bando, Kazunori E-mail: bkazunori@drl.co.jp; Taguchi, Kazumi; Ginoza, Yasushi; Naganuma, Tomoyoshi; Tanaka, Yoshitomo; Koike, Katsuo; Takatoku, Keizo

    2001-04-01

    To diagnose and investigate neurodegenerative diseases affecting cholinergic neuron density, piperazine derivatives of vesamicol were synthesized and evaluated. Previously, we reported that trans-5-iodo-2-hydroxy-3-[4-phenylpiperazinyl] tetralin (DRC140, 1) possessed high selectivity for vesicular acetylcholine transporter (VAChT). In present study of the effect of alkyl substituents, we observed that the introduction of a methyl group into the ortho or meta positions of the phenyl group of 1 increased affinity for VAChT. trans-5-Iodo-2-hydroxy-3-[4-[2-methylphenyl] piperazinyl]tetralin (2) displayed high affinity and specificity for VAChT. The regional distributions of radioactivity in the rat brain correlated well with known patterns of central cholinergic innervation. [{sup 123}I]2 is a potentially useful compound for SPECT imaging.

  3. Synthesis and biological evaluation of nitric oxide-releasing sixalkoxyl biphenyl derivatives as anticancer agents

    Institute of Scientific and Technical Information of China (English)

    Xiang Wen Kong; Yi Hua Zhang; Li Dai; Hui Ji; Yi Sheng Lai; Si Xun Peng

    2008-01-01

    A series of novel nitric oxide-donating sixalkoxyl biphenyl derivatives (14a-i)were synthesized by coupling furoxan with alkoxyl biphenyl skeleton using amino acids as the spacers,and their cytotoxicity against HepG2 cells in vitro were evaluated by MTr method.It was found that 14c,14d,14f,14i,14j and 14k showed more potent cytotoxic activities than control 5-fluorouracil.NO release assay of target compounds indicated that the maximum amount of NO released by most active compounds 14c and 14j was about 6 x 10-2μmol/L,whereas 14a and 14h with very weak activity only released NO of 1 x 10-μmol/L.

  4. Synthesis and biological evaluation of sophocarpinic acid derivatives as anti-HCV agents

    Directory of Open Access Journals (Sweden)

    Yinghong Li

    2014-08-01

    Full Text Available Chronic hepatitis C virus (HCV infection has become a major public health burden worldwide. Twenty-two sophocarpinic acid or matrine derivatives were synthesized and their anti-HCV activities were evaluated in vitro. The structure-activity analysis revealed that (i sophocarpinic acids with a D-seco 3-ring structure scaffold were more favorable than matrines with a 4-ring scaffold; (ii the introduction of an electron-withdrawing group on the phenyl ring in 12-N-benzenesulfonyl Δβγ sophocarpinic acids was beneficial for the antiviral activity against HCV. Among them, compounds 9h and 9j exhibited the most potent inhibitory activities on HCV replication with selectivity indies of 70.3 and 30.9, respectively. Therefore, both were selected as antiviral candidates for further investigation.

  5. Synthesis and biological evaluation of matrine derivatives as anti-hepatocellular cancer agents.

    Science.gov (United States)

    Wu, Lichuan; Liu, Shuaibing; Wei, Jinrui; Li, Dong; Liu, Xu; Wang, Jianyi; Wang, Lisheng

    2016-09-01

    We delineate herein the synthesis and anti-cancer effects of 15 matrine derivatives. The in vitro growth inhibitory assays showed that most of the prepared compounds exhibited improved anti-proliferative activities towards cancer cells with IC50 17-109 times lower than that of matrine. Compounds CH6 showed the most potent anti-proliferative activities in the four tested cancer cell lines. Moreover, compound CH6 could induce G1 cell cycle arrest and inhibit cell migration in human hepatocellular cancer cell lines Bel-7402 and HepG2 through up-regulation of P21, P27 and E-cadherin and down-regulation of N-cadherin.

  6. Synthesis of some novel D-glucuronic acid acetylated derivatives as potential anti-tumor agents.

    Science.gov (United States)

    El-Nezhawy, Ahmed O H; Adly, Frady G; Eweas, Ahmed F; Hanna, Atef G; El-Kholy, Yehya M; El-Sayed, Shahenaz H; El-Naggar, Tarek B A

    2011-10-01

    A structurally diverse series of Δ(4,5) -uronamide derivatives have been chemically synthesized starting from D-glucuronic acid itself by means of acetylation, activation, amide bond formation and base-catalyzed elimination protocols. Structure elucidation for all products along with optimization of the synthetic steps is described. The synthesized compounds were evaluated for their in-vitro anti-tumor activity against MCF-7, TK-10 and UACC-62 cell lines. The compounds 5, 11, 13, 15 and 16 were the most active against TK-10 cell line. On the other hand, the most active compounds against the MCF-7 cell line were 11 and 15. However, compounds 5, 7, 11, 13, 15 and 16 were the most active against the UACC-62 cell line.

  7. Synthesis, molecular modeling and structural characterization of vanillin derivatives as antimicrobial agents

    Science.gov (United States)

    Sun, Juan; Yin, Yong; Sheng, Gui-Hua; Yang, Zhi-Bo; Zhu, Hai-Liang

    2013-05-01

    Two vanillin derivatives have been designed and synthesized and their biological activities were also evaluated for antimicrobial activity. Their chemical structures are characterized by single crystal X-ray diffraction studies, 1H NMR, MS, and elemental analysis. Structural stabilization of them followed by intramolecular as well as intermolecular H-bonds makes these molecules as perfect examples in molecular recognition with self-complementary donor and acceptor units within a single molecule. Docking simulations have been performed to position compounds into the FtsZ active site to determine their probable binding model. Compound 3a shows the most potent biological activity, which may be a promising antimicrobial leading compound for the further research.

  8. Synthesis and Biological Evaluation of Novel Benzothiazole-2-thiol Derivatives as Potential Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Luo-Ting Yu

    2012-03-01

    Full Text Available A series of novel benzothiazole-2-thiol derivatives were synthesized and their structures determined by 1H-NMR, 13C-NMR and HRMS (ESI. The effects of all compounds on a panel of different types of human cancer cell lines were investigated. Among them, pyridinyl-2-amine linked benzothiazole-2-thiol compounds 7d, 7e, 7f and 7i exhibited potent and broad-spectrum inhibitory activities. Compound 7e displayed the most potent anticancer activity on SKRB-3 (IC50 = 1.2 nM, SW620 (IC50 = 4.3 nM, A549 (IC50 = 44 nM and HepG2 (IC50 = 48 nM and was found to induce apoptosis in HepG2 cancer cells.

  9. [Synthesis and biological evaluation of 2-(3-butynoicamidophenyl) benzothiazole derivatives as antitumor agents].

    Science.gov (United States)

    Yin, Gui-Lin; Li, Yan; Tang, Ke; Jin, Xiao-Feng; Chen, Xiao-Guang; Li, Li; Feng, Zhi-Qiang

    2014-06-01

    A series of 2-(3-butynoicamidophenyl)benzothiazole derivatives were synthesized starting from 4-fluoro-3-nitrobenzoic acid. Structures of all the synthesized compounds were confirmed by 1H NMR and HR-MS. Their antitumor activities against human tumor cells lines (HCT116, Mia-PaCa2, U87-MG, A549, NCI-H1975) were evaluated by MTT assay. The results revealed that most of the synthesized compounds showed potent activities against HCT116, Mia-PaCa2, U87-MG tumor cells lines. Particularly, compounds 14c and 14h exhibited better activity with IC50 values of 1 x 10(-8) mol x L(-1) against U87-MG and HCT116 respectively. The structure-activity relationship of compounds was also discussed preliminarily.

  10. Rational design and synthesis of novel diphenyl ether derivatives as antitubercular agents.

    Science.gov (United States)

    Kar, Sidhartha S; Bhat G, Varadaraj; Rao, Praveen Pn; Shenoy, Vishnu P; Bairy, Indira; Shenoy, G Gautham

    2016-01-01

    A series of triclosan mimic diphenyl ether derivatives have been synthesized and evaluated for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv. The binding mode of the compounds at the active site of enoyl-acyl carrier protein reductase of M. tuberculosis has been explored. Among them, compound 10b was found to possess antitubercular activity (minimum inhibitory concentration =12.5 µg/mL) comparable to triclosan. All the synthesized compounds exhibited low levels of cytotoxicity against Vero and HepG2 cell lines, and three compounds 10a, 10b, and 10c had a selectivity index more than 10. Compound 10b was also evaluated for log P, pKa, human liver microsomal stability, and % protein binding, in order to probe its druglikeness. Based on the antitubercular activity and druglikeness profile, it may be concluded that compound 10b could be a lead for future development of antitubercular drugs.

  11. Rational design and synthesis of novel diphenyl ether derivatives as antitubercular agents

    Science.gov (United States)

    Kar, Sidhartha S; Bhat G, Varadaraj; Rao, Praveen PN; Shenoy, Vishnu P; Bairy, Indira; Shenoy, G Gautham

    2016-01-01

    A series of triclosan mimic diphenyl ether derivatives have been synthesized and evaluated for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv. The binding mode of the compounds at the active site of enoyl-acyl carrier protein reductase of M. tuberculosis has been explored. Among them, compound 10b was found to possess antitubercular activity (minimum inhibitory concentration =12.5 µg/mL) comparable to triclosan. All the synthesized compounds exhibited low levels of cytotoxicity against Vero and HepG2 cell lines, and three compounds 10a, 10b, and 10c had a selectivity index more than 10. Compound 10b was also evaluated for log P, pKa, human liver microsomal stability, and % protein binding, in order to probe its druglikeness. Based on the antitubercular activity and druglikeness profile, it may be concluded that compound 10b could be a lead for future development of antitubercular drugs. PMID:27486307

  12. Synthesis and Biological Evaluation of Mannich Bases of Isoxazoline Derivatives as Novel Anti-Microbial Agents

    Directory of Open Access Journals (Sweden)

    Pawar Sudhir

    2012-01-01

    Full Text Available A novel series of compounds were synthesized by condensation reaction of substituted acetophenone (1a-b with substituted aldehyde (2a-b in presence of alcoholic sodium hydroxide to get intermediate chalcones (3a-c, which were further treated with hydroxylamine hydrochloride in presence of sodium hydroxide to get isoxazolines derivatives (4a-c. The latter were refluxed with substituted primary amines and formaldehyde for 6-10 h to afford Mannich bases. The synthesized compounds were characterized on the basis of their spectral (IR, 1HNMR data and evaluated for the antimicrobial activity by using Zone of Inhibition by cup plate method and Minimum Inhibitory Concentration by broth dilution method.

  13. Screening Antibacterial Agent from Crude Extract of Marine-Derived Fungi Associated with Soft Corals against MDR-Staphylococcus haemolyticus

    Science.gov (United States)

    Sabdaningsih, A.; Cristianawati, O.; Sibero, M. T.; Nuryadi, H.; Radjasa, O. K.; Sabdono, A.; Trianto, A.

    2017-02-01

    Multidrug resistant Staphylococcus haemolyticus is a Gram-positive bacteria and member of coagulase negative staphylococci (CoNS) which has the highest level of antimicrobial resistance. This nosocomial pathogen due to skin or soft tissue infections, bacteremia, septicemia, peritonitis, otitis media, meningitis and urinary tract infections. The ability to produce enterotoxins, hemolysins, biofilm, and cytotoxins could be an important characteristic for the successful of infection. Marine-derived fungi have potency as a continuous supply of bioactive compound. The aim of this research was screening antibacterial agent from crude extracts of marine-derived fungi associated with soft corals against MDR-S. haemolyticus. Among 23 isolates of marine-derived fungi isolated from 7 soft corals, there were 4 isolates active against MDR-S. haemolyticus. The screening was conducted by using agar plug diffusion method. Isolate PPSC-27-A4 had the highest antibacterial activity with diameter 23±9,6 mm. The crude extract from this isolate had been confirmed to antibacterial susceptibility test and it had the highest antibacterial activity in 12.2 mm with concentration of 300μg/ml from mycelia extract. PPSC-27-A4 had been characterized in molecular, based on the sequence analysis of 18S rRNA, PPSC-27-A4 isolate was identified as Trichoderma longibrachiatum.

  14. Synthesis and biological evaluation of novel 2,3-disubstituted quinoxaline derivatives as antileishmanial and antitrypanosomal agents.

    Science.gov (United States)

    Cogo, Juliana; Kaplum, Vanessa; Sangi, Diego Pereira; Ueda-Nakamura, Tânia; Corrêa, Arlene Gonçalves; Nakamura, Celso Vataru

    2015-01-27

    Quinoxalines belong to the N-containing heterocyclic compounds that stand out as having promising biological activity due to their privileged scaffold. In this work, we report the synthesis, antileishmanial, and antitrypanosomal properties of 46 new 2,3-disubstituted quinoxaline and 40 previously reported derivatives. Among all of the compounds screened for in vitro activity against epimastigotes and trypomastigotes of Trypanosoma cruzi and promastigotes of Leishmania amazonensis as well as mammalian toxicity on LLCMK2 cells and J774 macrophages, analogues from series 5, 6, 7, 9, 12, and 13 displayed high activity at micromolar IC50 and EC50 concentrations. Sixteen quinoxaline derivatives were selected and evaluated on T. cruzi and/or L. amazonensis amastigotes. The most active compounds were 6a-b and 7d-e, on all evolutive forms of L. amazonensis and T. cruzi evaluated with IC50 values 0.1-0.8 μM on promastigotes and epimastigotes 1.4-8.6 on amastigotes. Compounds 5k, 12b and 13a were the most selective (SI = 19.5-38.4) on amastigotes of T. cruzi. In general their activity was directly related to the methylsulfoxyl, methylsulfonyl, and amine groups as well as the presence of chorine or bromine in the molecules. The current results indicate that these quinoxaline derivatives are novel and promising agents for further development towards a treatment for Chagas' disease and leishmaniasis.

  15. Synthesis of Novel Oxime Sulfonate Derivatives of 2'(2',6')-(Di)chloropicropodophyllotoxins as Insecticidal Agents.

    Science.gov (United States)

    Wang, Rong; Zhi, Xiaoyan; Li, Jie; Xu, Hui

    2015-08-05

    To discover novel natural-product-based pesticidal agents, we prepared a series of oxime sulfonate derivatives of 2'(2',6')-(Di)chloropicropodophyllotoxins by structural modification of podophyllotoxin. Their structures were well-characterized by proton nuclear magnetic resonance ((1)H NMR), high-resolution mass spectrometry (HRMS), optical rotation, and melting point. Moreover, the key steric structure of compound 5f was unambiguously determined by single-crystal X-ray diffraction. Additionally, their insecticidal activity was evaluated at 1 mg/mL against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker), a typical lepidopteran pest. Among all derivatives, compounds 4c, 5c, and 5d exhibited more promising insecticidal activity, with the final mortality rates greater than 60%, when compared to their precursor podophyllotoxin and the positive control, toosendanin. It demonstrated that introduction of the chlorine atom at the C-2' or C-2',6' position on the E ring of picropodophyllotoxin or oxime sulfonate derivatives of picropodophyllotoxin was important for the insecticidal activity and introduction of a halogen (e.g., fluorine, chlorine, or bromine) atom-substituted phenylsulfonyl group on the oxime fragment of 2'(2',6')-(di)chloropicropodophyllones could lead to more promising compounds.

  16. Plant-derived antimalarial agents: new leads and efficient phythomedicines. Part I. Alkaloids

    Directory of Open Access Journals (Sweden)

    Alaíde B. Oliveira

    2009-12-01

    Full Text Available Malaria remains one of the most serious world health problem and the major cause of mortality and morbidity in the endemic regions. Brazil is among the 30 high-burden countries and most of the cases occur in the Legal Amazonian Region. New chemotherapeutical agents are needed for the treatment of malaria. Many plant species are used in traditional medicines of malarious countries and a relatively few number of these have been investigated for evaluation of their antimalarial effect. Still lower is the number of those that have had the active natural compounds isolated and the toxicity determined. This area is, then, of great research interest. discovery project of antimalarial natural products from plants traditionally used to treat malaria must include in vitro and in vivo assays as well as bioguided isolation of active compounds. The final products would be antimalarial chemical entities, potential new drugs or templates for new drugs development, and/or standardized antimalarial extracts which are required for pre-clinical and clinical studies when the aim is the development of effective and safe phythomedicines. This review discusses these two approaches, presents briefly the screening methodologies for evaluation of antimalarial activity and focuses the activity of alkaloids belonging to different structural classes as well as its importance as new antimalarial drugs or leads and chemical markers for phytomedicines.A malária ainda é um dos mais sérios problemas de saúde pública e a principal causa de mortalidade e morbidade nas regiões endêmicas. O Brasil está entre os 30 países com maior incidência de malária e a maior parte dos casos ocorre na Amazônia Legal. Novos agentes terapêuticos são necessários para o tratamento da malária. Muitas espécies vegetais são utilizadas na medicina tradicional de vários países endêmicos mas é relativamente reduzido o número daquelas que já foram investigadas quanto à sua atividade

  17. Design of Novel 4-Hydroxy-chromene-2-one Derivatives as Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Milan Mladenović

    2010-06-01

    Full Text Available This paper presents the design of novel 4-hydroxy-chromene-2 one derivatives, based on previously obtained minimal inhibitory concentration values (MICs, against twenty four microorganism cultures, Gram positive and negative bacteria and fungi. Two of our compounds, 3b (MIC range 130–500 μg/mL and 9c (31.25–62.5 μg/mL, presented high potential antimicrobial activity. The compound 9c had equal activity to the standard ketoconazole (31.25 μg/mL against M. mucedo. Enlarged resistance of S. aureus, E. coli and C. albicans on the effect of potential drugs and known toxicity of coumarin antibiotics, motivated us to establish SAR and QSAR models of activity against these cultures and correlate biological activity, molecular descriptors and partial charges of functional groups to explain activity and use for the design of new compounds. The QSAR study presents essential relation of antimicrobial activity and dominant substituents, 4-hydroxy, 3-acetyl and thiazole functional groups, also confirmed through molecular docking. The result was ten new designed compounds with much improved predicted inhibition constants and average biological activity.

  18. Rational design and synthesis of novel diphenyl ether derivatives as antitubercular agents

    Directory of Open Access Journals (Sweden)

    Kar SS

    2016-07-01

    Full Text Available Sidhartha S Kar,1 Varadaraj Bhat G,1 Praveen PN Rao,2 Vishnu P Shenoy,3 Indira Bairy,4 G Gautham Shenoy1 1Department of Pharmaceutical Chemistry, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, India; 2School of Pharmacy, Health Sciences Campus, University of Waterloo, Waterloo, ON, Canada; 3Department of Microbiology, Kasturba Medical College, Manipal, 4Melaka-Manipal Medical College, Manipal University, Manipal, India Abstract: A series of triclosan mimic diphenyl ether derivatives have been synthesized and evaluated for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv. The binding mode of the compounds at the active site of enoyl-acyl carrier protein reductase of M. tuberculosis has been explored. Among them, compound 10b was found to possess antitubercular activity (minimum inhibitory concentration =12.5 µg/mL comparable to triclosan. All the synthesized compounds exhibited low levels of cytotoxicity against Vero and HepG2 cell lines, and three compounds 10a, 10b, and 10c had a selectivity index more than 10. Compound 10b was also evaluated for log P, pKa, human liver microsomal stability, and % protein binding, in order to probe its druglikeness. Based on the antitubercular activity and druglikeness profile, it may be concluded that compound 10b could be a lead for future development of antitubercular drugs. Keywords: dihenyl ether, tuberculosis, cytotoxicity, druglikeness

  19. COX inhibitors Indomethacin and Sulindac derivatives as antiproliferative agents: synthesis, biological evaluation, and mechanism investigation.

    Science.gov (United States)

    Chennamaneni, Snigdha; Zhong, Bo; Lama, Rati; Su, Bin

    2012-10-01

    Cyclooxygenase (COX) inhibitors Indomethacin and its structural analogs Sulindac exhibit cell growth inhibition and apoptosis inducing activities in various cancer cell lines via COX independent mechanisms. In this study, the molecular structures of Indomethacin and Sulindac were used as starting scaffolds to design novel analogs and their effects on the proliferation of human cancer cells were evaluated. Compared to Indomethacin and Sulindac inhibiting cancer cell proliferation with IC(50)s of more than 1 mM, the derivatives displayed significantly increased activities. Especially, one of the Indomethacin analogs inhibited the growth of a series of cancer cell lines with IC(50)s around 0.5 μM-3 μM. Mechanistic investigation revealed that the new analog was in fact a tubulin inhibitor, although the parental compound Indomethacin did not show any tubulin inhibitory activity. Tubulin polymerization assay indicated this compound inhibited tubulin assembly at high concentrations, but promoted this process at low concentrations which is a very unique mechanism. The binding mode of this compound in tubulin was predicted using the molecular docking simulation.

  20. Human RNASET2 derivatives as potential anti-angiogenic agents: actin binding sequence identification and characterization

    Science.gov (United States)

    Nesiel-Nuttman, Liron; Doron, Shani; Schwartz, Betty; Shoseyov, Oded

    2015-01-01

    Human RNASET2 (hRNASET2) has been demonstrated to exert antiangiogenic and antitumorigenic effects independent of its ribonuclease capacity. We suggested that RNASET2 exerts its antiangiogenic and antitumorigenic activities via binding to actin and consequently inhibits cell motility. We focused herein on the identification of the actin binding site of hRNASET2 using defined sequences encountered within the whole hRNASET2 protein. For that purpose we designed 29 different hRNASET2-derived peptides. The 29 peptides were examined for their ability to bind immobilized actin. Two selected peptides-A103-Q159 consisting of 57 amino acids and peptide K108-K133 consisting of 26 amino acids were demonstrated to have the highest actin binding ability and concomitantly the most potent anti-angiogenic activity. Further analyses on the putative mechanisms associated with angiogenesis inhibition exerted by peptide K108-K133 involved its location during treatment within the HUVE cells. Peptide K108-K133 readily penetrates the cell membrane within 10 min of incubation. In addition, supplementation with angiogenin delays the entrance of peptide K108-K133 to the cell suggesting competition on the same cell internalization route. The peptide was demonstrated to co-localize with angiogenin, suggesting that both molecules bind analogous cellular epitopes, similar to our previously reported data for ACTIBIND and trT2-50. PMID:25815360

  1. Quinazoline derivatives as cathepsins B, H and L inhibitors and cell proliferating agents.

    Science.gov (United States)

    Raghav, Neera; Jangra, Suman; Kumar, Ajay; Bhattacharyya, Shalmoli

    2017-01-01

    Cysteine Cathepsins well known to be involved in cancer, inflammation and regulation of degenerative processes like apoptosis have become specific targets in drug designing. The potential of quinazolines and their derivatives in medicinal chemistry led us to synthesise a novel series of seven compounds of quinazolines to evaluate their effect on cathepsins and cellular aspects of HepG2 cells. In the present work we report the solvent free microwave assisted synthesis of (E)-8-benzylidene-5,6,7,8-tetrahydro-2,4-diarylquinazolines as inhibitors of mammalian hepatic cysteine proteases viz. Cathepsins B, H and L. In vitro inhibition of Cathepsins B, H and L is correlated well with in vitro studies when tested using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay on HepG2 cells, hepatocellular carcinoma cell line. The studies have been extended to evaluate the type of inhibition exhibited by the individual enzyme. Out of the seven compounds 1g i.e. (E)-8-(4-fluorobenzylidene)-4-(4-fluorophenyl)-2-phenyl-5, 6, 7, 8-tetrahydroquinazoline has been found to be most inhibitory for Cathepsins B, H and L to a maximum extent with the Ki values of 10(-10)M, 10(-10)M and 10(-9)M order respectively. In silico studies of all compounds have also been done at the active sites of Cathepsin B, H and L. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. 1,3-Oxazole derivatives as potential anticancer agents: Computer modeling and experimental study.

    Science.gov (United States)

    Semenyuta, Ivan; Kovalishyn, Vasyl; Tanchuk, Vsevolod; Pilyo, Stepan; Zyabrev, Vladimir; Blagodatnyy, Volodymyr; Trokhimenko, Olena; Brovarets, Volodymyr; Metelytsia, Larysa

    2016-12-01

    Microtubules play a significant role in cell growth and functioning. Therefore inhibition of the microtubule assemblies has emerged as one of the most promising cancer treatment strategies. Predictive QSAR models were built on a series of selective inhibitors of the tubulin were performed by using Associative Neural Networks (ANN). To overcome the problem of data overfitting due to the descriptor selection, a 5-fold cross-validation with variable selection in each step of the analysis was used. All developed QSAR models showed excellent statistics on the training (total accuracy: 0.96-0.97) and test sets (total accuracy: 0.95-97). The models were further validated by 11 synthesized 1,3-oxazole derivatives and all of them showed inhibitory effect on the Hep-2 cancer cell line. The most promising compound showed inhibitory activity IC50=60.2μM. In order to hypothesize their mechanism of action the top three compounds were docked in the colchicine binding site of tubulin and showed reasonable docking scores as well as favorable interactions with the protein.

  3. Clinical status of anti-cancer agents derived from marine sources.

    Science.gov (United States)

    Singh, Ram; Sharma, Mukul; Joshi, Penny; Rawat, Diwan S

    2008-08-01

    The chemical, biological and ecological diversity of the marine ecosystem has contributed immensely in the discovery of extremely potent compounds that have shown potent activities in antitumor, analgesia, antiinflammatory, immunomodulation, allergy, anti-viral etc. The compounds of marine origin are diverse in structural class from simple linear peptides to complex macrocyclic polyethers. The recent advances in the sophisticated instruments for the isolation and characterization of marine natural products and development of high-throughput screening, have substantially increased the rate of discovery of various compounds of biomedical application. Didemnin was the first marine peptide that entered in human clinical trials in US for the treatment of cancer and other compounds such as dolastatin-10, soblidotin, didemnin B, ecteinascidin 743, girolline, aplidine, cryptophycins (also arenastatin A), bryostatin 1, ILX 651, kahalalide F, E7389, discodermolide, ES-285 (spisulosine), HTI-286 (hemiasterlin derivative), squalamine, KRN-7000, vitilevuamide, Laulimalide, Curacin A, diazonamide, peloruside A, eleutherobin, sarcodictyin, thiocoraline, salicylihalimides A, ascididemnin, CGX-1160, CGX-1007dictyodendrins, GTS-21 (aka DMBX), manoalide, IPL-576,092 (aka HMR-4011A) have entered in the clinical trials. This article summarize clinical status and synthetic advances of some of these compounds.

  4. Effects of feeding plant-derived agents on the colonization of Campylobacter jejuni in broiler chickens.

    Science.gov (United States)

    Kurekci, Cemil; Al Jassim, Rafat; Hassan, Errol; Bishop-Hurley, Sharon L; Padmanabha, Jagadish; McSweeney, Christopher S

    2014-09-01

    The aim of this work was to test the potential use of plant-derived extracts and compounds to control Campylobacter jejuni in broiler chickens. Over a 7-wk feeding period, birds were fed a commercial diet with or without plant extracts (Acacia decurrens, Eremophila glabra), essential oil [lemon myrtle oil (LMO)], plant secondary compounds [terpinene-4-ol and α-tops (including α-terpineol, cineole, and terpinene-4-ol)], and the antibiotic virginiamycin. Traditional culture and real-time quantitative PCR techniques were used to enumerate the numbers of C. jejuni in chicken fecal and cecal samples. In addition, BW and feed intake were recorded weekly for the calculation of BW gain and feed conversion ratio. The mean log10 counts of C. jejuni were similar (P > 0.05) across treatments. However, significantly lower levels of fecal Campylobacter counts (P 0.05) in BW gain were obtained for dietary supplementation, except for the E. glabra extract, which had a negative impact (P < 0.001) on BW, resulting in sporadic death. Results from this study suggest that supplemental natural compounds used in the current study did not reduce the shedding of C. jejuni to desired levels.

  5. A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents

    Institute of Scientific and Technical Information of China (English)

    CHEN JinCan; QIAN Li; SHEN Yong; CHEN LanMei; ZHENG KangCheng

    2008-01-01

    A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis.A new scheme deter-mining outliers by "leave-one-out" (LOO) cross-validation coefficient (q2n-1) was suggested and suc-cessfully used.In the established optimal equation (excluding two outliers), the steric parameter (MRR) and the net charge (QFR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (IgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds.The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values are 0.883 and 0.797, respectively.It indicates that this model has a significantly statistical quality and an excellent prediction ability.Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally.

  6. A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis. A new scheme determining outliers by "leave-one-out" (LOO) cross-validation coefficient (q2n-i) was suggested and successfully used. In the established optimal equation (excluding two outliers), the steric parameter (MRR) and the net charge (QFR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (lgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds. The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values are 0.883 and 0.797, respectively. It indicates that this model has a significantly statistical quality and an excellent prediction ability. Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally.

  7. Development of superior bone scintigraphic agent from a series of {sup 99m}Tc-labeled zoledronic acid derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jianguo [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Qiu Ling, E-mail: qiulingwx@gmail.com [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Cheng Wen [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Luo Shineng, E-mail: shineng914@yahoo.com.cn [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Xue Li; Zhang Shu [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China)

    2012-05-15

    Two novel zoledronic acid (ZL) derivatives, 1-hydroxy-4-(1H-imidazol-1-yl)butane-1,1-diyldiphosphonic acid (IBDP) and 1-hydroxy-5-(1H-imidazol-1-yl)pentane-1,1-diyldiphosphonic acid (IPeDP), were prepared and labeled with the radionuclide technetium-99m in a high labeling yield. In vitro stabilities of these radiolabeled complexes were measured by the radio-HPLC analysis as a function of time, which showed excellent stability with the radiochemical purity of over 95% at 6 h post preparation. Their in vivo biological performances were evaluated and compared with those of {sup 99m}Tc-ZL and {sup 99m}Tc-MDP (methylenediphosphonic acid). The biodistribution in mice and scintigraphic images of the rabbit showed that the tracer agent {sup 99m}Tc-IPeDP had highly selective uptake in the skeletal system and rapid clearance from the blood and soft tissues and an excellent scintigraphic image can be obtained in a shorter time post injection with clear visualization of the skeleton and low soft tissue activity. These preclinical studies suggest that {sup 99m}Tc-IPeDP would be a novel superior bone scintigraphic agent. - Highlights: Black-Right-Pointing-Pointer Two novel diphosphonic acids were labeled with the {sup 99m}Tc in high labeling yield. Black-Right-Pointing-Pointer {sup 99m}Tc-IPeDP had high uptake in skeletal system and rapid clearance from blood. Black-Right-Pointing-Pointer {sup 99m}Tc-IPeDP reveals attractive biological features as superior bone scanning agent.

  8. Production of ethoxylated fatty acids derived from Jatropha non-edible oil as a nonionic fat-liquoring agent.

    Science.gov (United States)

    El-Shattory, Y; Abo-Elwafa, Ghada A; Aly, Saadia M; Nashy, El-Shahat H A

    2012-01-01

    Natural fatty derivatives (oleochemicals) have been used as intermediate materials in several industries replacing the harmful and expensive petrochemicals. Fatty ethoxylates are one of these natural fatty derivatives. In the present work Jatropha fatty acids were derived from the non edible Jatropha oil and used as the fat source precursor. The ethoxylation process was carried out on the derived fatty acids using a conventional cheap catalyst (K₂CO₃) in order to obtain economically and naturally valuable non-ionic surfactants. Ethoxylation reaction was proceeded using ethylene oxide gas in the presence of 1 or 2% K₂CO₃ catalyst at 120 and 145°C for 5, 8 and 12 hours. The prepared products were evaluated for their chemical and physical properties as well as its application as non- ionic fat-liquoring agents in leather industry. The obtained results showed that the number of ethylene oxide groups introduced in the fatty acids as well as their EO% increased as the temperature and time of the reaction increased. The highest ethoxylation number was obtained at 145°C for 8 hr. Also, the prepared ethoxylated products were found to be effective fat-liquors with high HLB values giving stable oil in water emulsions. The fat-liquored leather led to an improvement in its mechanical properties such as tensile strength and elongation at break. In addition, a significant enhancement in the texture of the treated leather by the prepared fat-liquors as indicated from the scanning electron microscope (SEM) images was observed.

  9. 2H-chromene derivatives bearing thiazolidine-2,4-dione, rhodanine or hydantoin moieties as potential anticancer agents.

    Science.gov (United States)

    Azizmohammadi, Mohammad; Khoobi, Mehdi; Ramazani, Ali; Emami, Saeed; Zarrin, Abdolhossein; Firuzi, Omidreza; Miri, Ramin; Shafiee, Abbas

    2013-01-01

    A variety of (Z)-[(2H-chromen-3-yl)methylene]azolidinones 6a-t bearing thiazolidine-2,4-dione, rhodanine or hydantoin scaffolds were designed and synthesized as potential anticancer agents. Inhibitory effect of synthesized compounds 6a-t on the viability of cancer and non-cancer cells was assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) reduction assay. The SAR study revealed that the N-substitution of azolidinone moiety cannot improve the activity but S/NH replacement (thiazolidine-2,4-dione/hydantoin) and S/O alteration (rhodanine/thiazolidine-2,4-dione) enable us to modulate the growth inhibition activity against various cell lines. Moreover, 6-bromo and 2-methyl substituents on chromene ring had positive effects on growth inhibitory activity depending on the tumor cell lines. Among the synthesized compounds, hydantoin derivative 6o with a 6-bromo-2-methyl-2H-chromene substructure showed the best profile of cytotoxicity comparable to that of cisplatin as standard anticancer agent. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  10. Design, development, drug-likeness, and molecular docking studies of novel piperidin-4-imine derivatives as antitubercular agents.

    Science.gov (United States)

    Revathi, Rajappan; Venkatesha Perumal, Ramachandran; Pai, Karkala Sreedhara Ranganath; Arunkumar, Govindakarnavar; Sriram, Dharmarajan; Kini, Suvarna Ganesh

    2015-01-01

    Tuberculosis remains one of the major grievous diseases worldwide. The emergence of resistance to antituberculosis drugs emphasize the necessity to discover new therapeutic agents for preferential tuberculosis therapy. In this study, various novel 1-(1H-benzimidazol-2-ylmethyl) piperidin-4-imine derivatives were developed and checked for favorable pharmacokinetic parameters based on drug-likeness explained by Lipinski's rule of five. All 20 of the novel chemical entities were found to possess a favorable pharmacokinetic profile since they were not violating Lipinski's rule of five. The title compounds were also synthesized, characterized, and tested for ex vivo antitubercular activity against Mycobacterium tuberculosis H37Rv (ATCC27294). The results revealed that four compounds (2-[1-(1H-benzimidazol-2-ylmethyl)piperidin-4-ylidene] hydrazinecarbothioamide, 2-[1-(1H-benzimidazol-2-ylmethyl)piperidin-4-ylidene]-N-hydroxy-hydrazinecarbo-thioamide, 1-[1-(1H-benzimidazol-2-ylmethyl)piperidin-4-ylidene]guanidine, and 2-[1-(1H-benzimidazol-2-ylmethyl)piperidin-4-ylidene]hydrazinecarboxamide) were the most potent (minimum inhibitory concentration 6.25 µg/mL) antitubercular agents, with less toxicity (selectivity index more than 10). The molecules were also subjected to three-dimensional molecular docking on the crystal structure of enoyl-acyl carrier protein (EACP) reductase enzyme (code 1ZID, Protein Data Bank), which represents a good prediction of the interactions between the molecules and EACP reductase with minimum binding energy.

  11. Design, synthesis, and biological evaluation of scutellarein carbamate derivatives as potential multifunctional agents for the treatment of Alzheimer's disease.

    Science.gov (United States)

    Sang, Zhi-Pei; Qiang, Xiao-Ming; Li, Yan; Wu, Bei; Zhang, Hui; Zhao, Ming-Gao; Deng, Yong

    2015-11-01

    A series of scutellarein carbamate derivatives were designed and synthesized based on the multitarget-directed drug design strategy for treatment of Alzheimer's disease. Their acetylcholinesterase and butyrylcholinesterase inhibitory activities, antioxidant activities, metals chelation, and neuroprotective effects against hydrogen peroxide-induced PC12 cell injury were evaluated in vitro. The preliminary results indicated that compound 7b exhibited good inhibitory potency toward AChE and BuChE with IC50 values of 1.2 ± 0.03 μm and 22.1 ± 0.15 μm, respectively, possessed the strong antioxidant potency (10.3 trolox equivalents), as well as acted as a selective metal chelator and neuroprotective agent. Furthermore, 7b could improve memory impairment induced by scopolamine, ethanol, and sodium nitrite using the step-down passive avoidance task in vivo and could remarkably decrease the activity of acetylcholinesterase in mice brain. This study indicated that 7b could be considered as a potential multitarget agent against AD. © 2015 John Wiley & Sons A/S.

  12. Synthesis, evaluation and QSAR studies of 16-(4 & 3,4-substituted) benzylidene androstene derivatives as anticancer agents.

    Science.gov (United States)

    Dubey, S; Kaur, P; Jindal, D P; Satyanarayan, Y D; Piplani, P

    2008-05-01

    In a systematic effort aimed at identifying new steroidal cytotoxic agents with potent antipoliferative activity against cancer cells and developing their QSAR models, series of 4-nitro, 4-isopropyl, 4-methoxy and 3,4-dimethoxy substituted benzylidene androst-5-ene derivatives were synthesized. The selected compounds were evaluated for antineoplastic activity against a panel of three human cell lines-breast, CNS and lungs at NCI, Bethesda, USA. The results presented herein reports that compounds 7, 9, 10, 15,16, 18, 20-25, 30, 32-36 and 44 have been found to be active anticancer agents. The QSAR of 20 compounds was performed separately for each cell line and best-fit QSAR models are developed. The QSAR models obtained have shown significant correlations (r(2) range: 0.9163 to 0.8164) and good predictive performance (q(2) range: 0.8499- 0.6320). The validation of models has also been performed using the test set of compounds 5, 15 and 44.

  13. Synthesis and Evaluation of New Pyrazoline Derivatives as Potential Anticancer Agents in HepG-2 Cell Line

    Directory of Open Access Journals (Sweden)

    Weijie Xu

    2017-03-01

    Full Text Available Cancer is a major public health concern worldwide. Adverse effects of cancer treatments still compromise patients’ quality of life. To identify new potential anticancer agents, a series of novel pyrazoline derivatives were synthesized and evaluated for cytotoxic effects on HepG-2 (human liver hepatocellular carcinoma cell line and primary hepatocytes. Compound structures were confirmed by 1H-NMR, mass spectrometry, and infrared imaging. An in vitro assay demonstrated that several compounds exerted cytotoxicity in the micromolar range. Benzo[b]thiophen-2-yl-[5-(4-hydroxy-3,5-dimethoxy-phenyl-3-(2-hydroxy-phenyl-4,5-dihydo-pyrazol-1-yl]-methanone (b17 was the most effective anticancer agent against HepG-2 cells owing to its notable inhibitory effect on HepG-2 with an IC50 value of 3.57 µM when compared with cisplatin (IC50 = 8.45 µM and low cytotoxicity against primary hepatocytes. Cell cycle analysis and apoptosis/necrosis evaluation using this compound revealed that b17 notably arrested HepG-2 cells in the G2/M phase and induced HepG-2 cells apoptosis. Our findings indicate that compound b17 may be a promising anticancer drug candidate.

  14. Discovery of indeno[1,2-b]quinoxaline derivatives as potential anticancer agents.

    Science.gov (United States)

    Tseng, Chih-Hua; Chen, You-Ren; Tzeng, Cherng-Chyi; Liu, Wangta; Chou, Chon-Kit; Chiu, Chien-Chih; Chen, Yeh-Long

    2016-01-27

    We have synthesized certain indeno[1,2-b]quinoxaline derivatives for antiproliferative evaluation. Among them, 11-{[3-(dimethylamino)propoxy]imino}-N-[3-(dimethylamino) propyl]-11H-indeno[1,2-b]quinoxaline-6-carboxamide (10a) was active against the growth of MDA-MB231, PC-3, and Huh-7 with IC50 values of 0.87 (selectivity index, SI = 36.22), 0.82 (SI = 38.43), and 0.64 μM (SI = 49.23) respectively. Compound 10a was inactive against the growth of normal human fetal lung fibroblast cell line (MRC-5) with an IC50 value of 31.51 μM. Its analogs, 10b and 10c, were also active against the growth of MB231, PC-3, and Huh-7 with IC50 values of <1.0 μM in each case. Our results have also indicated compounds 10a-10c exhibited comparable inhibitory activities against topo I and topo II with the positive compound 2 at a concentration of 10 μM. Mechanism studies indicated that compound 10a induced cell cycle arrest at S phase via activation of caspase-3, -7 and an increase in the protein expression of Bad and Bax but a decrease in expression of Bcl-2 and PARP, which consequently cause cell death. In addition, compound 10a attenuated the levels of phosphorylated Src, Akt-1, and Akt-2 protein levels but did not affect the total protein expression of Akt. We have also implanted human hepatocellular carcinoma cells into the yolk sac of zebrafish larvae and incubated larvae with various concentrations of 10a. Our results of the zebrafish xenograft assay confirmed the anti-tumor effect of 10ain vivo.

  15. Causation and Responsibility: A New Direction

    Directory of Open Access Journals (Sweden)

    Matt Mortellaro

    2009-04-01

    Full Text Available In “Property, Causality, and Liability” and “Causation and Aggression,” Hans-Hermann Hoppe and Stephan Kinsella & Patrick Tinsley, respectively, argue against the Rothbardian position on criminal liability, especially with regard to the issue of incitement. This essay takes a critical look at the suggested approaches of both and attempts to defend the Rothbardian position on incitement from their criticisms. Further, this essay examines the views of Walter Block on incitement and attempts to correct inconsistencies in his position with regard to murder contracts and threats.

  16. Design, synthesis, and anticancer activity of novel berberine derivatives prepared via CuAAC "click" chemistry as potential anticancer agents.

    Science.gov (United States)

    Jin, Xin; Yan, Tian-Hua; Yan, Lan; Li, Qian; Wang, Rui-Lian; Hu, Zhen-Lin; Jiang, Yuan-Ying; Sun, Qing-Yan; Cao, Yong-Bing

    2014-01-01

    A series of novel derivatives of phenyl-substituted berberine triazolyls has been designed and synthesized via copper-catalyzed azide-alkyne cycloaddition click chemistry in an attempt to develop antitumor agents. All of the compounds were evaluated for anticancer activity against a panel of three human cancer cell lines, including MCF-7 (breast), SW-1990 (pancreatic), and SMMC-7721 (liver) and the noncancerous human umbilical vein endothelial cell (HUVEC) cell lines. The results indicated that most of the compounds displayed notable anticancer activities against the MCF-7 cells compared with berberine. Among these derivatives, compound 16 showed the most potent inhibitory activity against the SW-1990 and SMMC-7721 cell lines, with half-maximal inhibitory concentration (IC50) values of 8.54±1.97 μM and 11.87±1.83 μM, respectively. Compound 36 exhibited the most potent inhibitory activity against the MCF-7 cell line, with an IC50 value of 12.57±1.96 μM. Compound 16 and compound 36 exhibited low cytotoxicity in the HUVEC cell line, with IC50 values of 25.49±3.24 μM and 30.47±3.47 μM. Furthermore, compounds 14, 15, 16, 17, 18, 32, and 36 exhibited much better selectivity than berberine toward the normal cell line HUVEC.

  17. Comparison of dual-echo DSC-MRI- and DCE-MRI-derived contrast agent kinetic parameters.

    Science.gov (United States)

    Quarles, C Chad; Gore, John C; Xu, Lei; Yankeelov, Thomas E

    2012-09-01

    The application of dynamic susceptibility contrast (DSC) MRI methods to assess brain tumors is often confounded by the extravasation of contrast agent (CA). Disruption of the blood-brain barrier allows CA to leak out of the vasculature leading to additional T(1), T(2) and T(2) relaxation effects in the extravascular space, thereby affecting the signal intensity time course in a complex manner. The goal of this study was to validate a dual-echo DSC-MRI approach that separates and quantifies the T(1) and T(2) contributions to the acquired signal and enables the estimation of the volume transfer constant, K(trans), and the volume fraction of the extravascular extracellular space, v(e). To test the validity of this approach, DSC-MRI- and dynamic contrast enhanced (DCE) MRI-derived K(trans) and v(e) estimates were spatially compared in both 9L and C6 rat brain tumor models. A high degree of correlation (concordance correlation coefficients >0.83, Pearson's r>0.84) and agreement was found between the DSC-MRI- and DCE-MRI-derived measurements. These results indicate that dual-echo DSC-MRI can be used to simultaneously extract reliable DCE-MRI kinetic parameters in brain tumors in addition to conventional blood volume and blood flow metrics.

  18. Hypoxia-mimetic agents inhibit proliferation and alter the morphology of human umbilical cord-derived mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Zeng Hui-Lan

    2011-08-01

    Full Text Available Abstract Background The therapeutic efficacy of human mesenchymal stem cells (hMSCs for the treatment of hypoxic-ischemic diseases is closely related to level of hypoxia in the damaged tissues. To elucidate the potential therapeutic applications and limitations of hMSCs derived from human umbilical cords, the effects of hypoxia on the morphology and proliferation of hMSCs were analyzed. Results After treatment with DFO and CoCl2, hMSCs were elongated, and adjacent cells were no longer in close contact. In addition, vacuole-like structures were observed within the cytoplasm; the rough endoplasmic reticulum expanded, and expanded ridges were observed in mitochondria. In addition, DFO and CoCl2 treatments for 48 h significantly inhibited hMSCs proliferation in a concentration-dependent manner (P Conclusions The hypoxia-mimetic agents, DFO and CoCl2, alter umbilical cord-derived hMSCs morphology and inhibit their proliferation through influencing the cell cycle.

  19. Design, synthesis and biological evaluation of tricyclic diterpene derivatives as novel neuroprotective agents against ischemic brain injury.

    Science.gov (United States)

    Wang, Ying-Ying; Gao, Yuan-Xue; Gao, Wei; Xu, Yuan; Xu, Ya-Zhou; Wang, Yun-Jie; Chang, Sai; Yu, Li-Gang; Zhang, Lu-Yong; Liao, Hong; Yang, Lian-Fang; Pang, Tao; Qiu, Wen-Wei

    2015-10-20

    Lead compound 7 has neuroprotective effects, and it was discovered by screening a small synthetic natural product-like (NPL) library. Based on the lead, a series of tricyclic diterpene derivatives was designed and synthesized, and their neuroprotective effects were further evaluated against glutamate-, oxygen and glucose deprivation (OGD)- and nutrient deprivation-induced neuronal injury using cell-based assays. To our delight, most of these synthetic compounds exhibited increased neuroprotective effects and blood-brain barrier (BBB) permeability without cellular toxicity. The most potent compound, compound 30, showed significantly improved neuroprotection against neuronal injury in primary neurons. Furthermore, compound 30 exhibited remarkable neuroprotection in transient middle cerebral artery occlusion (tMCAO) rats by reducing their infarct sizes and neurological deficit scores. A mechanistic exploration using in vitro and in vivo experiments showed that the neuroprotection of these compounds was at least partly mediated by improving the levels of glutathione (GSH), superoxide dismutase (SOD) and heme oxygenase-1 (HO-1) protein. Therefore, these tricyclic diterpene derivatives could be used as promising leads for the development of a new type of neuroprotective agents against ischemic brain injury.

  20. Preparation, characterization and technological evaluation of CMC derived from rice-straw as thickening agents in discharge, discharge-resist and burn-out printing.

    Science.gov (United States)

    Ragheb, A A; Nassar, S H; Abd El-Thalouth, I; Ibrahim, M A; Shahin, A A

    2012-08-01

    Carboxymethyl cellulose samples of different D.S. values were prepared from rice straw via pulping followed by etherification with monochloroacetic acid under the catalytic action of sodium hydroxide. The prepared derivatives were assessed for D.S., rheological properties as well as suitability as thickening agents in different printing styles. It was found that carboxymethyl cellulose derived from rice straw is characterized by a non-Newtonian pseudoplastic behavior and its apparent viscosity at any specific rate of shear depends on the D.S. All the prepared derivatives could be used successfully as thickening agents in discharge and/or discharge/resist printing of cotton fabrics. Furthermore, they could be used also as thickening agent for burn-out printing style of wool/polyester blended fabrics using sodium hydroxide. Attractive samples could be obtained via using these techniques.

  1. Two-way causation in life satisfaction research : Structural equation models with granger causation

    NARCIS (Netherlands)

    Headey, Bruce; Muffels, R.J.A.

    2014-01-01

    Two-way causation issues are the bete noire of life satisfaction research. As acknowledged in several landmark reviews, many variables routinely reported as causes or determinants of life satisfaction could equally well be consequences, or perhaps both causes and consequences (Diener, 1984; Diener,

  2. Febrile Seizure: Demographic Features and Causative Factors

    Directory of Open Access Journals (Sweden)

    Hamed ESMAILI GOURABI

    2012-10-01

    Full Text Available ObjectiveBecause of geographical and periodical variation, we prompted to determine the demographic features and causative factors for febrile seizure in Rasht.Materials & MethodsIn this cross-sectional study, all 6–month- to 6-year-old children with the diagnosis of febrile seizure admitted to 17 Shahrivar hospital in Rasht, from August, 2009 to August, 2010 were studied. Age, sex, family history of the disease, seizure types, body temperature upon admission and infectious causes of the fever were recorded. All statistical analysis was performed with SPSS software, version 16.ResultsOf the 214 children (mean age, 25.24±15.40 months, 124 were boys and 109 had a positive family history. Complex seizures were seen in 39 cases. In patients with a complex febrile seizure, 59% had the repetitive type, 20.5% had the focal type and 20.5% had more than 15 minutes duration of seizures. Most of the repetitive seizures (78.3% occurred in patients under 2 years old; the difference between under and over 2-year-old patients was statistically significant (P=0.02. Study results did not show significant differences between the two genders for simple or complex seizures. The mean body temperature upon admission was 38.2±1.32◦C (38.31±0.82 degrees in boys and 38.04±1.78 in girls. Upper respiratory infections were seen in most patients (74.29%. All cases of lower respiratory infections were boys. There was a statistically significant difference between boys and girls in causes of fever.ConclusionMost of the children had a positive family history and the most common causative factor was upper respiratory infection.

  3. Vulvovaginal candidiasis in Mato Grosso, Brazil: pregnancy status, causative species and drugs tests

    Directory of Open Access Journals (Sweden)

    Luciana Basili Dias

    2011-12-01

    Full Text Available Causative agent in majority of VVC is Candida albicans, but infection due to non-C. albicans is common. Use of empiric antifungal therapy in Brazil due to syndromic management of vulvovaginitis could act as risk factor for increase resistance among VVC causative agents. From Mato Grosso patients, 160 with culture-proved among 404 women who had clinical symptoms of VVC, were enrolled in this study. 70 non-pregnant women and 90 pregnant women were included. Candida albicans was the most prevalent, representing 72.9% in the non-pregnant group and 92.3% in the pregnant group. Differences in species distribution were noted between the two groups, being C. parapsilosis the second more prevalent species among non-pregnant women. Susceptibility testing revealed high susceptibility to fluconazole (except for C. krusei, itraconazole, ketoconazole, and amphotericin B regardless the species (C. albicans, C. parapsilosis, C. tropicalis, C. glabrata, C. krusei analyzed.

  4. Use of paramagnetic chelated metal derivatives of polysaccharides and spin-labeled polysaccharides as contrast agents in magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bligh, S.W.; Harding, C.T.; Sadler, P.J.; Bulman, R.A.; Bydder, G.M.; Pennock, J.M.; Kelly, J.D.; Latham, I.A.; Marriott, J.A. (Department of Chemistry, Birkbeck College, London (England))

    1991-02-01

    Soluble and insoluble polysaccharides were derivatized with diethylenetriaminepentaacetic acid (DTPA) and/or spin-labeled with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO). Polysaccharides derivatized with DTPA were prepared via cyanogen bromide activation, coupling to a diamine linker, and to DTPA anhydride. Spin-labeled polysaccharides were also prepared via cyanogen bromide activation. The extent of derivatization for dextran (18 kDa) was about 120 glucose units per DTPA, and for cellulose and starch about 15-30 units per DTPA. For spin-labeled polysaccharides, the average loading ranged from 1 nitroxide per 16 glucose units for starch to 181 for dextran (82 kDa). These derivatized paramagnetic polysaccharides were shown to be more effective relaxants than the small paramagnetic molecules alone. Both soluble and insoluble polysaccharide-linker-DTPA-Gd(3) complexes were effectively cleared from the body (rats) after oral administration. After intravenous administration, the biodistribution of dextran-linker-DTPA-Gd(3) complexes differed significantly from that of GdDTPA. Reduction of the nitroxide by ascorbic acid was retarded in the polysaccharide derivatives, particularly in starch derivatized with both nitroxide and linker-DTPA-Cu(2). These agents showed contrast enhancement in the gastrointestinal tract of rabbits.

  5. Synthesis and Biological Evaluation of Novel Dehydroabietic Acid Derivatives Conjugated with Acyl-Thiourea Peptide Moiety as Antitumor Agents

    Directory of Open Access Journals (Sweden)

    Le Jin

    2015-06-01

    Full Text Available A series of dehydroabietic acid (DHAA acyl-thiourea derivatives were designed and synthesized as potent antitumor agents. The in vitro pharmacological screening results revealed that the target compounds exhibited potent cytotoxicity against HeLa, SK-OV-3 and MGC-803 tumor cell lines, while they showed lower cytotoxicity against HL-7702 normal human river cells. Compound 9n (IC50 = 6.58 ± 1.11 μM exhibited the best antitumor activity against the HeLa cell line and even displayed more potent inhibitory activity than commercial antitumor drug 5-FU (IC50 = 36.58 ± 1.55 μM. The mechanism of representative compound 9n was then studied by acridine orange/ethidium bromide staining, Hoechst 33,258 staining, JC-1 mitochondrial membrane potential staining, TUNEL assay and flow cytometry, which illustrated that this compound could induce apoptosis in HeLa cells. Cell cycle analysis indicated that compound 9n mainly arrested HeLa cells in the S phase stage. Further investigation demonstrated that compound 9n induced apoptosis of HeLa cells through a mitochondrial pathway.

  6. Synthesis and biological evaluation of novel phosphoramidate derivatives of coumarin as chitin synthase inhibitors and antifungal agents.

    Science.gov (United States)

    Ji, Qinggang; Ge, Zhiqiang; Ge, Zhixing; Chen, Kaizhi; Wu, Hualong; Liu, Xiaofei; Huang, Yanrong; Yuan, Lvjiang; Yang, Xiaolan; Liao, Fei

    2016-01-27

    A series of novel phosphoramidate derivatives of coumarin have been designed and synthesized as chitin synthase (CHS) inhibitors. All the synthesized compounds have been screened for their chitin synthase inhibition activity and antimicrobial activity in vitro. The bioactive assay manifested that most of the target compounds exhibited good efficacy against CHS and a variety of clinically important fungal pathogens. In particular, compound 7t with IC50 of 0.08 mM against CHS displayed stronger efficiency than the reference Polyoxin B with IC50 of 0.16 mM. In addition, the apparent Ki values of compound 7t was 0.096 mM while the Km of Chitin synthase prepared from Candida tropicalis was 3.86 mM for UDP-N-acetylglucosamine, and the result of the Ki showed that the compounds was a non-competitive inhibitor of the CHS. As far as the antifungal activity is concerned, compounds 7o, 7r and 7t were highly active against Aspergillus flavus with MIC values in the range of 1 μg/mL to 2 μg/Ml while the results of antibacterial screening showed that these compounds have negligible actions to the tested bacteria. These results indicated that the design of these compounds as antifungal agents was rational.

  7. Synthesis and biological evaluation of novel fluorine-containing stilbene derivatives as fungicidal agents against phytopathogenic fungi.

    Science.gov (United States)

    Jian, Weilin; He, Daohang; Xi, Pinggen; Li, Xinwei

    2015-11-18

    The rising development of resistance to conventional fungicides is driving the search for new alternative candidates to control plant diseases. In this study, a series of new fluorine-containing stilbene derivatives was synthesized on the basis of our previous quantitative structure-activity relationship analysis results. Bioassays in vivo revealed that the title compounds exhibited potent fungicidal activities against phytopathogenic fungi (Colletotrichum lagenarium and Pseudoperonospora cubensis) from cucumber plants. In comparison to the previous results, the introduction of a fluorine moiety showed improved activities of some compounds against those fungi. Notably, compound 9 exhibited a control efficacy against C. lagenarium (83.4 ± 1.3%) comparable to that of commercial fungicide (82.7 ± 1.7%). For further understanding the possible mode of action of the stilbene against C. lagenarium, the effects on hyphal morphology, electrolyte leakage, and respiration of mycelial cell suspension were studied. Microscopic observation showed considerably deformed mycelial morphology. The conductivity of mycelial suspension increased in the presence of compound 9, whereas no significantly inhibitory effect on respiration was observed. Taken together, the fungicidal mechanism of this stilbene is associated with its membrane disruption effect, resulting in increased membrane permeability. These results provide important clues for mechanistic study and derivatization of stilbenes as alternative sources of fungicidal agents for plant disease control.

  8. Discovery of 5-(5,5-Dimethylbutenolide-3-ethylidene)-2-amino-imidazolinone Derivatives as Fungicidal Agents.

    Science.gov (United States)

    Tang, Bo; Yang, Mingyan; Zhao, Yu; Kong, Lingqing; Wang, Weiwei; Wang, Mingan

    2015-07-28

    The novel fungicidal agents 5-(5,5-dimethylbutenolide-3-ethylidene)-2-amino-imidazolinone derivatives, were designed and synthesized in moderate to excellent yields in four steps by αa-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS and 1H-NMR. The preliminary bioassay showed that some of these compounds, such as 4a, 4e and 5g exhibit 94.9%, 92.8% and 81.4% inhibition rates against Sclerotinia scleotiorum at the concentration of 50 µg/mL, respectively. The EC50 values of compounds 4e and 4i were 4.14 and 3.27 µM against Alternaria Solani, and 5g had EC50 value of 3.23 µM against S. scleotiorum. Compounds 4d and 4g displayed 98.0% and 97.8% control of spore germination against Botrytis cinerea at the concentration of 100 µg/mL, respectively.

  9. Discovery of 5-(5,5-Dimethylbutenolide-3-ethylidene-2-amino-imidazolinone Derivatives as Fungicidal Agents

    Directory of Open Access Journals (Sweden)

    Bo Tang

    2015-07-01

    Full Text Available The novel fungicidal agents 5-(5,5-dimethylbutenolide-3-ethylidene-2-amino-imidazolinone derivatives, were designed and synthesized in moderate to excellent yields in four steps by αa-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS and 1H-NMR. The preliminary bioassay showed that some of these compounds, such as 4a, 4e and 5g exhibit 94.9%, 92.8% and 81.4% inhibition rates against Sclerotinia scleotiorum at the concentration of 50 µg/mL, respectively. The EC50 values of compounds 4e and 4i were 4.14 and 3.27 µM against Alternaria Solani, and 5g had EC50 value of 3.23 µM against S. scleotiorum. Compounds 4d and 4g displayed 98.0% and 97.8% control of spore germination against Botrytis cinerea at the concentration of 100 µg/mL, respectively.

  10. Mental Causation and the Causal Completeness of Physics

    Directory of Open Access Journals (Sweden)

    Wilson Mendonça

    2002-06-01

    Full Text Available This paper takes issue with a widely accepted view of mental causation. This is the view that mental causation is either reducible to physical causation or ultimately untenable, because incompatible with the causal completeness of physics The paper examines, first, why recent attempts to save the phenomena of mental causation by way of the notion of supervenient causation fail The result of t/us examination is the claim that any attempted specification of the most basic causal factors which supposedly underlie a causal transaction cannot account for the counterfactually necessary connections with the effect m question. By contrast, the specification of these factors at a higher-level would allow establishing such connections. The paper doses with a discussion of how the view of autonomous higher-level causation grounded on counterfactual relations can be made compatible with the physicalistic commitment to a complete specification of the particular causes of any physical effect exclusively in physical terms.

  11. Recent progress in fungus-derived bioactive agents for targeting of signaling machinery in cancer cells

    Directory of Open Access Journals (Sweden)

    Lin X

    2015-03-01

    Full Text Available Xiukun Lin,1 Ammad Ahmad Farooqi,2 Muhammad Ismail2 1Department of Pharmacology, Capital Medical University, Beijing, People’s Republic of China; 2Institute of Biomedical and Genetic Engineering, Islamabad, Pakistan Abstract: It is becoming increasingly understood that tumor cells may have different mutations and dependencies on diverse intracellular signaling cascades for survival or metastatic potential. Overexpression of oncogenes, inactivation of tumor suppressor genes, genetic/epigenetic mutations, genomic instability, and loss of apoptotic cell death are some of the mechanisms that have been widely investigated in molecular oncology. We partition this multicomponent review into the most recent evidence on the anticancer activity of fungal substances obtained from in vitro and xenografted models, and these fungal substances modulate expression of oncogenic and tumor suppressor miRNAs.  There are some outstanding questions regarding fungus-derived chemical-induced modulation of intracellular signaling networks in different cancer cell lines and preclinical models. Certain hints have emerged, emphasizing mechanisms via which apoptosis can be restored in TRAIL-resistant cancer cells. Reconceptualization of the knowledge obtained from these emerging areas of research will enable us to potentially identify natural agents with notable anticancer activity and minimal off-target effects. Integration of experimentally verified evidence obtained from cancer cell line gene expression with large-scale functional screening results and pharmacological sensitivity data will be helpful in identification of therapeutics with substantial efficacy. New tools and technologies will further deepen our understanding of the signaling networks that underlie the development of cancer, metastasis, and resistance to different therapeutics at both a personal and systems-wide level. Keywords: fungal products, cell signaling, cancer, apoptosis, miRNA, xenograft

  12. Synthesis and quantitative structure-activity relationship (QSAR) study of novel isoxazoline and oxime derivatives of podophyllotoxin as insecticidal agents.

    Science.gov (United States)

    Wang, Yi; Shao, Yonghua; Wang, Yangyang; Fan, Lingling; Yu, Xiang; Zhi, Xiaoyan; Yang, Chun; Qu, Huan; Yao, Xiaojun; Xu, Hui

    2012-08-29

    In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, 33 isoxazoline and oxime derivatives of podophyllotoxin modified in the C and D rings were synthesized and their structures were characterized by Proton nuclear magnetic resonance ((1)H NMR), high-resolution mass spectrometry (HRMS), electrospray ionization-mass spectrometry (ESI-MS), optical rotation, melting point (mp), and infrared (IR) spectroscopy. The stereochemical configurations of compounds 5e, 5f, and 9f were unambiguously determined by X-ray crystallography. Their insecticidal activity was evaluated against the pre-third-instar larvae of northern armyworm, Mythimna separata (Walker), in vivo. Compounds 5e, 9c, 11g, and 11h especially exhibited more promising insecticidal activity than toosendanin, a commercial botanical insecticide extracted from Melia azedarach . A genetic algorithm combined with multiple linear regression (GA-MLR) calculation is performed by the MOBY DIGS package. Five selected descriptors are as follows: one two-dimensional (2D) autocorrelation descriptor (GATS4e), one edge adjacency indice (EEig06x), one RDF descriptor (RDF080v), one three-dimensional (3D) MoRSE descriptor (Mor09v), and one atom-centered fragment (H-052) descriptor. Quantitative structure-activity relationship studies demonstrated that the insecticidal activity of these compounds was mainly influenced by many factors, such as electronic distribution, steric factors, etc. For this model, the standard deviation error in prediction (SDEP) is 0.0592, the correlation coefficient (R(2)) is 0.861, and the leave-one-out cross-validation correlation coefficient (Q(2)loo) is 0.797.

  13. Cumulative Causation, Market Transition, and Emigration from China

    Science.gov (United States)

    Liang, Zai; Chunyu, Miao David; Zhuang, Guotu; Ye, Wenzhen

    2009-01-01

    In this paper, we report findings from a recent survey of international migration from China's Fujian province to the United States. We take advantage of the ethnosurvey approach as used in the Mexican Migration Project. Surveys were done in migrant-sending communities in China as well as in destination communities of New York City. We derive hypotheses from two strands of recent studies-the international migration literature and the market transition debate. Our results are in general consistent with hypotheses derived from cumulative causation of migration. However, because of the geographical location of China as compared to Mexico, there are some differences between the two countries in terms of particular migration patterns to the United States. As expected, at the community level, migration prevalence ratio (measuring migration networks) increases the propensity of migration for other members in the community. In contrast, having a household member migrated previously does not increase the propensity of migration of other household members until debt for previous migration is paid off. Our research clearly demonstrates the value of bringing the case of China into the comparative study of international migration. With respect to market transition theory, we find that political power continues to be an important factor in the order of social stratification in the coastal Fujian province. PMID:19569396

  14. Entropy and Information Transmission in Causation and Retrocausation

    Science.gov (United States)

    Moddel, Garret

    2006-10-01

    Although experimental evidence for retrocausation exists, there are clearly subtleties to the phenomenon. The bilking paradox, in which one intervenes to eliminate a subsequent cause after a preceding effect has occurred, appears on the surface to show that retrocausation is logically impossible. In a previous paper, the second law of thermodynamics was invoked to show that the entropy in each process of a psi interaction (presentience, telepathy, remote perception, and psychokinesis) cannot decrease, prohibiting psi processes in which signals condense from background fluctuations. Here it is shown, perhaps contrary to one's intuition, that reversible processes cannot be influenced through retrocausation, but irreversible processes can. The increase in thermodynamic entropy in irreversible processes — which are generally described by Newtonian mechanics but not Lagrangian dynamics and Hamilton's Principle — is required for causation. Thermodynamically reversible processes cannot be causal and hence also cannot be retrocausal. The role of entropy in psi interactions is extended by using the bilking paradox to consider information transmission in retroactive psychokinesis (PK). PK efficiency, ηPK, is defined. A prediction of the analysis is that ηPK ⩽ H/H0, where H is the information uncertainty or entropy in the retro-PK agent's knowledge of the event that is to be influenced retrocausally. The information entropy can provide the necessary ingredient for non-reversibility, and hence retrocausation. Noise and bandwidth limitations in the communication to the agent of the outcome of the event increase the maximum PK efficiency. Avoidance of the bilking paradox does not bar a subject from using the premonition of an event to prevent it from occurring. The necessity for large information entropy, which is the expected value of the surprisal, is likely to be essential for any successful PK process, not just retro-PK processes. Hence uncertainty in the

  15. Design, synthesis and study of quinoxaline-2- carboxamide 1,4-DI-N-Oxide derivatives as anti-tuberculosis agents

    OpenAIRE

    Moreno-Viguri, E. (Elsa); Monge, A; Perez-Silanes, S. (Silvia)

    2013-01-01

    The experimental work presented in this memory is based on the hypothesis that quinoxalines di-N-oxide, considered to be the core of the structure, which present a carboxamide moiety on position two and aliphatic linker between this group and an aromatic system, can be proposed as potent anti-tuberculosis agents. The main purpose of this project is the synthesis of new quinoxaline di-N-oxide derivatives as anti-tuberculosis agents. The strategy consists of the design and synthesis of several ...

  16. Febrile Seizure: Demographic Features and Causative Factors

    Directory of Open Access Journals (Sweden)

    Hamed ESMAILI GOURABI

    2013-01-01

    Full Text Available How to cite this article: Esmaili Gourabi H, Bidabadi E, Cheraghalipour  F, Aarabi  Y, Salamat F. Febrile Seizure: Demographic Features and Causative Factors. Iran J Child Neurol Autumn 2012; 6(4:33-37.Abstract Objective Because of geographical and periodical variation, we prompted to determine the demographic features and causative factors for febrile seizure in Rasht. Materials & Methods In this cross-sectional study, all 6–month- to 6-year-old children with the diagnosis of febrile seizure admitted to 17 Shahrivar hospital in Rasht, from August, 2009 to August, 2010 were studied. Age, sex, family history of the disease, seizure types, body temperature upon admission and infectious causes of the fever were recorded. All statistical analysis was performed with SPSS software, version 16. Results Of the 214 children (mean age, 25.24±15.40 months, 124 were boys and 109 had a positive family history. Complex seizures were seen in 39 cases. In patients with a complex febrile seizure, 59% had the repetitive type, 20.5% had the focal type and 20.5% had more than 15 minutes duration of seizures. Most of the repetitive seizures (78.3% occurred in patients under 2 years old; the difference between under and over 2-year-old patients was statistically significant (P=0.02. Study results did not show significant differences between the two genders for simple or complex seizures. The mean body temperature upon admission was 38.2±1.32◦C (38.31±0.82 degrees in boys and 38.04±1.78 in girls. Upper respiratory infections were seen in most patients (74.29%. All cases of lower respiratory infections were boys. There was a statistically significant difference between boys and girls in causes of fever. Conclusion Most of the children had a positive family history and the most common causative factor was upper respiratory infection.  References: Huang MC, Huang CC, Thomas K. Febrile convulsions: development and validation of a questionnaire to measure

  17. The Development of the Causative Construction in Persian Child Language

    Science.gov (United States)

    Family, Neiloufar; Allen, Shanley E. M.

    2015-01-01

    The acquisition of systematic patterns and exceptions in different languages can be readily examined using the causative construction. Persian allows four types of causative structures, including one productive multiword structure (i.e. the light verb construction). In this study, we examine the development of all four structures in Persian child…

  18. New modified β-cyclodextrin derivatives as detoxifying agents of chemical warfare agents (II). In vitro detoxification of cyclosarin (GF): general screening and toxicokinetic aspects of OP scavengers.

    Science.gov (United States)

    Müller, Susanne; Estour, François; Kalakuntla, Raman Kumar; Le Provost, Romain; Lafont, Olivier; Worek, Franz; Thiermann, Horst; Reiter, Georg

    2013-02-04

    As standard therapy of intoxication with organophosphorus (OP) compounds is still insufficient, developing new treatment strategies is urgently required. For evaluating potential of OP detoxification of several compounds correctly, different toxicodynamic impact of OP enantiomers has to be considered thoroughly. It has already been demonstrated that β-cyclodextrin (β-CD) derivatives with attached nucleophilic substituent iodosobenzoic acid (IBA) can be regarded as potent OP scavengers due to an accelerating effect on decay of different OP. Herein, six CD derivatives permethylated or not on CD torus as well as differently attached nucleophilic substituent IBA derivative were investigated regarding detoxification of GF as an OP model substance. Acceleration of GF detoxification could be detected for all compounds with highest rate constants for propylene chain linked nucleophilic substituents on CD derivative. In addition, fast initial binding of GF on CD could be observed and is ascribed to formation of CD complexes. Furthermore, terminal plateau phase was detected of about 1% of each enantiomer reflecting the necessity of a quantitative determination at low concentrations. Moreover, this molecular depot formation may represent an additional detoxification pathway for OP. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  19. Optimization of the pyrolysis process for the production of a biomass derived reducing agent and hydrogen-rich gases

    OpenAIRE

    Adrados López de Viñaspre, Aitziber

    2014-01-01

    221 p. [EN] This thesis is devoted to the optimization of the biomass pyrolysis process for the simultaneous production of bioreducing agents and high value gases. The thesis is part of the existing collaborative research work between the Befesa Steel R&D S.L. Company and the Chemical and Environmental Engineering Department of the Faculty of Engineering of Bilbao. This company was interested in developing the pyrolysis process at large scale to produce biocoke to be used as reducing agent...

  20. Factual and legal causation - their relation to negligence in nursing.

    Science.gov (United States)

    Turton, Gemma

    Several elements must be shown to be fulfilled for a court to hold that negligence has occurred, and a person is liable. One of these elements is 'causation', the idea that there must be a causal link between the claimant's loss and the negligent behaviour of the defendant. This article considers the application of the tests of factual and legal causation to cases of medical negligence. It is argued that in light of the recent development of a number of exceptional approaches to factual causation, each relating to a particular causal problem, the causal process must be identified in any given case so that the correct test for factual causation can be applied. This is illustrated by reference to MRSA claims. It is further argued that where the negligence consists of misdiagnosis or mistreatment of existing illness the causal problem is unique to medical negligence and demands a unique approach to causation. The 'scope of duty' test for legal causation is illustrated in a medical context and it is argued that where the negligence consists of a failure to warn the patient of the risks involved in treatment, although the harm is clearly within the scope of the doctor's duty, it is wrong to establish liability in the absence of factual causation.

  1. Tissue engineered bulking agent with adipose-derived stem cells and silk fibroin microspheres for the treatment of intrinsic urethral sphincter deficiency.

    Science.gov (United States)

    Shi, Li Bing; Cai, Hong Xia; Chen, Long Kun; Wu, Yan; Zhu, Shou An; Gong, Xiao Nan; Xia, Ya Xian; Ouyang, Hong Wei; Zou, Xiao Hui

    2014-02-01

    In this study we developed a tissue engineered bulking agent that consisted of adipose-derived stem cells (ADSCs) and silk fibroin microspheres to treat stress urinary incontinence caused by severe intrinsic sphincter deficiency (ISD). ISD models were established by completely transection of the bilateral pudendal nerve (PNT) and confirmed by the decreased leak-point pressure (LPP) and increased lumen area of urethra. Injection of silk fibroin microspheres could recover LPP and lumen area at 4 weeks but its efficacy disappears at 8, 12 weeks. Moreover, it was exciting to find that tissue engineered bulking agent brought long-term efficacy (at 4, 8, 12 weeks post-injection) on the recovery of LPP and lumen area. Concomitantly with the function, tissue engineered bulking agent treated group also improved the urethral sphincter structure as exhibited by better tissue regeneration. The findings showed that silk fibroin microspheres alone could work effectively in short-term, while tissue engineered bulking agent that combined silk fibroin microspheres with ADSCs exhibited promising long-term efficacy. This study developed a new strategy of tissue engineered bulking agent for future ISD therapy.

  2. A computable expression of closure to efficient causation.

    Science.gov (United States)

    Mossio, Matteo; Longo, Giuseppe; Stewart, John

    2009-04-07

    In this paper, we propose a mathematical expression of closure to efficient causation in terms of lambda-calculus; we argue that this opens up the perspective of developing principled computer simulations of systems closed to efficient causation in an appropriate programming language. An important implication of our formulation is that, by exhibiting an expression in lambda-calculus, which is a paradigmatic formalism for computability and programming, we show that there are no conceptual or principled problems in realizing a computer simulation or model of closure to efficient causation. We conclude with a brief discussion of the question whether closure to efficient causation captures all relevant properties of living systems. We suggest that it might not be the case, and that more complex definitions could indeed create crucial some obstacles to computability.

  3. DNA-binding antitumor agents: from pyrimido[5,6,1-de]acridines to other intriguing classes of acridine derivatives.

    Science.gov (United States)

    Antonini, Ippolito

    2002-09-01

    In the field of antitumor DNA-binding agents, the class of acridine derivatives play an important role either as number of compounds or as importance of their anticancer properties. We have synthesized a number of acridine derivatives as potential antitumor drugs, in which the chromophore is fully or partially constituted by acridine or by 9-acridone ring systems: from the pyrimido[5,6,1-de]acridines, to the pyrimido[4,5,6-kl]acridines, the bis(amine-functionalized) 9-acridone-4-carboxamides, the bis(amine-functionalized) acridine-4-carboxamides, and the pyrazolo[3,4,5-kl]acridine-5-carboxamides. In the present revue we will describe the rational design, the synthesis, and the salient biological characteristics of these classes of acridine derivatives.

  4. Natural products-based insecticidal agents 7. Semisynthesis and insecticidal activity of novel 4alpha-alkyloxy-2-chloropodophyllotoxin derivatives against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Xu, Hui; Xiao, Xiao; Wang, Qing-tian

    2010-09-01

    In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, 16 novel 4alpha-alkyloxy-2-chloropodophyllotoxin derivatives were semisynthesized from podophyllotoxin, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo. Among all the tested derivatives, especially compounds 4b, 4e, 4g, and 4p exhibited more promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach. Generally, it was obviously demonstrated that the length of straight-chain or branched-chain alkyloxy, and heteroatom-containing cycloalkyloxy at the C-4 position of 2-chloropodophyllotoxin were very important for the insecticidal activity.

  5. Al Ghazali and Hume on causation and miracles

    OpenAIRE

    yazıcı, sedat

    2010-01-01

    This paper is an attempt to show the similarities and differences between Al Ghazali and Hume on causation and miracles. Such a comparison is interesting because, long before Hume, the issue of necessary causality had been taken up by the Islamic philosophers Al Ghazal in his book The Incoherence the Philosophers. Although Ghazali's and Hume's views on causation are strikingly parallel to one another in their empirical contention, there are still some differences to be noted. First, both reje...

  6. RAPID MULTICOMPONENT ANALYSIS OF HEMOGLOBIN DERIVATIVES FOR CONTROLLED ANTIDOTAL USE OF METHEMOGLOBIN-FORMING AGENTS IN CYANIDE POISONING

    NARCIS (Netherlands)

    ZIJLSTRA, WG

    When cyanide poisoning is treated with a methemoglobin-forming agent, oxidative metabolism is protected at the expense of the oxygen capacity of the blood.The affinity of methemoglobin for CN- is high enough to compete with cytochrome oxidase, which protects the latter from becoming blocked, but all

  7. RAPID MULTICOMPONENT ANALYSIS OF HEMOGLOBIN DERIVATIVES FOR CONTROLLED ANTIDOTAL USE OF METHEMOGLOBIN-FORMING AGENTS IN CYANIDE POISONING

    NARCIS (Netherlands)

    ZIJLSTRA, WG

    1993-01-01

    When cyanide poisoning is treated with a methemoglobin-forming agent, oxidative metabolism is protected at the expense of the oxygen capacity of the blood.The affinity of methemoglobin for CN- is high enough to compete with cytochrome oxidase, which protects the latter from becoming blocked, but all

  8. CNS-specific regulatory elements in brain-derived HIV-1 strains affect responses to latency-reversing agents with implications for cure strategies

    Science.gov (United States)

    Gray, L R; Cowley, D; Welsh, C; Lu, H K; Brew, B J; Lewin, S R; Wesselingh, S L; Gorry, P R; Churchill, M J

    2016-01-01

    Latency-reversing agents (LRAs), including histone deacetylase inhibitors (HDACi), are being investigated as a strategy to eliminate latency in HIV-infected patients on suppressive antiretroviral therapy. The effectiveness of LRAs in activating latent infection in HIV strains derived from the central nervous system (CNS) is unknown. Here we show that CNS-derived HIV-1 strains possess polymorphisms within and surrounding the Sp transcription factor motifs in the long terminal repeat (LTR). These polymorphisms result in decreased ability of the transcription factor specificity protein 1 to bind CNS-derived LTRs, reducing the transcriptional activity of CNS-derived viruses. These mutations result in CNS-derived viruses being less responsive to activation by the HDACi panobinostat and romidepsin compared with lymphoid-derived viruses from the same subjects. Our findings suggest that HIV-1 strains residing in the CNS have unique transcriptional regulatory mechanisms, which impact the regulation of latency, the consideration of which is essential for the development of HIV-1 eradication strategies. PMID:26303660

  9. Synthesis and Regioselective Reaction of Some Unsymmetrical Heterocyclic Chalcone Derivatives and Spiro Heterocyclic Compounds as Antibacterial Agents.

    Science.gov (United States)

    El-Hashash, Maher A; Rizk, Sameh A; Atta-Allah, Saad R

    2015-12-10

    A number of novel heterocyclic chalcone derivatives can be synthesized by thermal and microwave tools. Treatment of 4-(4-Acetylamino- and/or 4-bromo-phenyl)-4-oxobut-2-enoic acids with hydrogen peroxide in alkaline medium were afforded oxirane derivatives 2. Reaction of the epoxide 2 with 2-amino-5-aryl-1,3,4-thiadiazole derivatives yielded chalcone of imidazo[2,1-b]thiadiazole derivative 4 via two thermal routes. In one pot reaction of 4-bromoacetophenone, diethyloxalate, and 2-amino-5-aryl-1,3,4-thiadiazole derivatives in MW irradiation (W 250 and T 150 °C) under eco-friendly conditions afforded an unsuitable yield of the desired chalcone 4d. The chalcone derivatives 4 were used as a key starting material to synthesize some new spiroheterocyclic compounds via Michael and aza-Michael adducts. The chalcone 4f was similar to the aryl-oxo-vinylamide derivatives for the inhibition of tyrosine kinase and cancer cell growth. The electron-withdrawing substituents, such as halogens, and 2-amino-1,3,4-thiadiazole moeity decreasing the electron density, thereby decreasing the energy of HOMO, and the presence of imidazothiadiazole moiety should improve the antibacterial activity. Thus, the newly synthesized compounds were evaluated for their anti-bacterial activity against (ATCC 25923), (ATCC 10987), (ATCC 274,) and (SM514). The structure of the newly synthesized compounds was confirmed by elemental analysis and spectroscopic data.

  10. Synthesis and biological activity of ester derivatives of mycophenolic acid and acridines/acridones as potential immunosuppressive agents.

    Science.gov (United States)

    Cholewinski, Grzegorz; Iwaszkiewicz-Grzes, Dorota; Trzonkowski, Piotr; Dzierzbicka, Krystyna

    2016-12-01

    Improved derivatives of mycophenolic acid (MPA) are necessary to reduce the frequency of adverse effects, this drug exerts in treated patients. In this study, MPA was coupled with N-(ω-hydroxyalkyl)-9-acridone-4-carboxamides or N-(ω-hydroxyalkyl)acridine-4-carboxamides to give respective ester conjugates upon Yamaguchi protocol. This esterification required protection of phenol group in MPA. Designed conjugates revealed higher potency in vitro than parent MPA. Acridine derivatives were more active than acridone analogs and length of the alkyl linker between MPA and heterocyclic units influenced the observed cytotoxicity. Derivatives 2b, 2d, 3a, 3b displayed the most promising immunosuppressive activity.

  11. Nocardia harenae, an uncommon causative organism of mycetoma: report on two patients.

    Science.gov (United States)

    Kresch-Tronik, Nicole S; Carrillo-Casas, Erika M; Arenas, Roberto; Atoche, Carlos; Ochoa-Carrera, Luis A; Xicohtencatl-Cortes, Juan; Manjarrez-Hernández, Angel H; Hernández-Castro, Rigoberto

    2012-08-01

    Mycetoma is the most frequently diagnosed deep mycosis in Mexico and is caused, in 86% of cases, by Nocardia brasiliensis. Worldwide, Nocardia harenae has not been previously reported as a causative agent of human mycetoma. Herein we report, to our knowledge, the first two human cases of mycetoma due to N. harenae in a clinical setting. The strains were identified by phenotypic and molecular techniques. Both cases were characterized by long-lasting mycetoma that had previously been failed to be cured and had shown resistance to therapy. However, in our hospital, a multidrug therapy proved to be effective in these cases.

  12. Burkholderia mallei and Burkholderia pseudomallei: the causative micro-organisms of glanders and melioidosis.

    Science.gov (United States)

    Gilad, Jacob

    2007-11-01

    Burkholderia mallei and Burkholderia pseudomallei are the causative micro-organisms of Glanders and Melioidosis, respectively. Although now rare in Western countries, both micro-organisms have recently gained much interest because of their unique potential as bioterrorism agents. This paper reviews the epidemiology, pathogenesis, diagnosis and treatment of Melioidosis and Glanders. Recent patents relating to these micro-organisms, especially potential vaccines, are presented. Continued research and development is urgently needed, especially in regard to rapid and accurate diagnosis of melioidosis and glanders, efficacious therapy and primary and secondary prevention.

  13. Fat on sale: role of adipose-derived stem cells as anti-fibrosis agent in regenerative medicine.

    Science.gov (United States)

    Gupta, Manoj K; Ajay, Amrendra Kumar

    2015-12-01

    The potential use of stem cells for cell-based tissue repair and regeneration offers alternative therapeutic strategies for various diseases. Adipose-derived stem cells (ADSCs) have emerged as a promising source of stem cells suitable for transplantation in regenerative medicine and wound repair. A recent publication in Stem Cell Research & Therapy by Zhang and colleagues reports a new finding about the anti-fibrosis role of ADSCs and conditioned media derived from them on hypertrophic scar formation in vivo.

  14. Experimental and clinical trials of new /sub 99m/Tc-labeled hepatobiliary agents. [Iminodiacetic acid derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Wistow, B.W.; Subramanian, G.; Gagne, G.M.; Henderson, R.W.; McAfee, J.G.; Hall, R.C.; Grossman, Z.D.

    1978-09-01

    Several new derivatives of lidocaine were synthesized and used to examine the intra- and extrahepatic bile ducts and gallbladder. Diisopropyl-IDA exhibited approximately twice the bile concentration of /sup 131/I-rose bengal during the first hour after injection. P-butyl-IDA also concentrates moderately well in the bile and has the added advantage of very low excretion into the urine (2%). It seems more effective than the other IDA derivatives at high bilirubin levels.

  15. Micelle swelling agent derived cavities for increasing hydrophobic organic compound removal efficiency by mesoporous micelle@silica hybrid materials

    KAUST Repository

    Shi, Yifeng

    2012-06-01

    Mesoporous micelle@silica hybrid materials with 2D hexagonal mesostructures were synthesized as reusable sorbents for hydrophobic organic compounds (HOCs) removal by a facile one-step aqueous solution synthesis using 3-(trimethoxysily)propyl-octadecyldimethyl-ammonium chloride (TPODAC) as a structure directing agent. The mesopores were generated by adding micelle swelling agent, 1,3,5-trimethyl benzene, during the synthesis and removing it afterward, which was demonstrated to greatly increase the HOC removal efficiency. In this material, TPODAC surfactant is directly anchored on the pore surface of mesoporous silica via SiOSi covalent bond after the synthesis due to its reactive Si(OCH 3) 3 head group, and thus makes the synthesized materials can be easily regenerated for reuse. The obtained materials show great potential in water treatment as pollutants sorbents. © 2011 Elsevier Inc. All rights reserved.

  16. Substituted piperazines as nootropic agents: 2- or 3-phenyl derivatives structurally related to the cognition-enhancer DM235.

    Science.gov (United States)

    Guandalini, Luca; Martino, Maria Vittoria; Di Cesare Mannelli, Lorenzo; Bartolucci, Gianluca; Melani, Fabrizio; Malik, Ruchi; Dei, Silvia; Floriddia, Elisa; Manetti, Dina; Orlandi, Francesca; Teodori, Elisabetta; Ghelardini, Carla; Romanelli, Maria Novella

    2015-04-15

    A series of 2-phenyl- or 3-phenyl piperazines, structurally related to DM235 and DM232, two potent nootropic agents, have been prepared and tested in the mouse passive-avoidance test, to assess their ability to revert scopolamine-induced amnesia. Although the newly synthesized molecules were less potent than the parent compounds, some useful information has been obtained from structure-activity relationships. A small but significant enantioselectivity has been found for the most potent compound 5a.

  17. Human plasma-derived BuChE as a stoichiometric bioscavenger for treatment of nerve agent poisoning.

    Science.gov (United States)

    Mumford, Helen; Docx, Cerys J; Price, Matthew E; Green, A Christopher; Tattersall, John E H; Armstrong, Stuart J

    2013-03-25

    Potent organophosphorous (OP) agents, such as VX, are hazardous by absorption through the skin and are resistant to conventional pharmacological antidotal treatments. The residence time of a stoichiometric bioscavenger, human butyrylcholinesterase (huBuChE), in the plasma more closely matches that of VX than do the residence times of conventional therapy drugs (oxime, anti-muscarinic, anticonvulsant). Intramuscular (i.m.) huBuChE afforded almost complete protection when administered prior to the onset of observable cholinergic signs of VX poisoning, but once signs of poisoning became evident the efficacy of i.m. huBuChE decreased. A combination of nerve agent therapy drugs (oxime, anti-muscarinic, anticonvulsant) with huBuChE (i.m.) protected 100% (8/8) of guinea-pigs from a lethal dose of VX (0.74 mg/kg) to 48 h, even when administered on signs of poisoning. Survival was presumed to be due to immediate alleviation of the cholinergic crisis by the conventional pharmacological treatment drugs, in conjunction with bioscavenger that prevented further absorbed agent reaching the AChE targets. Evidence to support this proposed mechanism of action was obtained from PKPD experiments in which multiple blood samples and microdialysate samples were collected from individual conscious ambulatory animals. Plasma concentrations of intramuscularly-administered atropine, diazepam and HI-6 reached a peak within 15 min and were eliminated rapidly within 4h. Plasma concentrations of huBuChE administered by the i.m. route took approximately 24h to reach a peak, but were well-maintained over the subsequent 7days. Thus, the pharmacological therapy rapidly treated the initial signs of poisoning, whilst the bioscavenger provided prolonged protection by neutralising further nerve agent entering the bloodstream and preventing it from reaching the target organs.

  18. Synthesis and Pharmacophore Modelling of 2,6,9-Trisubstituted Purine Derivatives and Their Potential Role as Apoptosis-Inducing Agents in Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Jeannette Calderón-Arancibia

    2015-04-01

    Full Text Available A series of 2,6,9-trisubstituted purine derivatives have been synthesized and investigated for their potential role as antitumor agents. Twelve compounds were obtained by a three step synthetic procedure using microwave irradiation in a pivotal step. All compounds were evaluated in vitro to determine their potential effect on cell toxicity by the MTT method and flow cytometry analysis on four cancer cells lines and Vero cells. Three out of twelve compounds were found to be promising agents compared to a known and effective anticancer drug, etoposide, in three out of four cancer cell lines assayed with considerable selectivity. Preliminary flow cytometry data suggests that compounds mentioned above induce apoptosis on these cells. The main structural requirements for their activity for each cancer cell line were characterized with a preliminary pharmacophore model, which identified aromatic centers, hydrogen acceptor/donor center and a hydrophobic area. These features were consistent with the cytotoxic activity of the assayed compounds.

  19. Design and synthesis of novel tetrahydro-2H-Pyrano[3,2-c]pyridazin-3(6H)-one derivatives as potential anticancer agents.

    Science.gov (United States)

    Al-Tel, Taleb H

    2010-12-01

    Polyfunctional tetrahydro-2H-pyrano[3,2-c]pyridazin-3(6H)-one derivatives were synthesized and biologically evaluated as novel anticancer agents. These motifs were produced by a five-step reaction sequence in which the Achmatowicz oxidative cyclization, is the basic core for such synthesis. Compounds 15f, 16c, and 16d showed antiproliferative activity against the SK-BR-3 breast cancer cell line. Importantly, 16c and 16d showed the highest efficacy, being approximately 30-fold more potent against SK-BR-3 (IC50 0.21 and 0.15 μM, respectively) compared to other cancer cell lines tested. In addition, 16c and 16d displayed about 295 fold less toxicity against normal breast cell line MCF10A compared to SK-BR-3 breast cancer cells. These compounds form the foundation for further investigation in our continuing efforts to develop potent anticancer agents.

  20. Structure-activity relationship study of pyrimido[1,2-c][1,3]benzothiazin-6-imine derivatives for potent anti-HIV agents.

    Science.gov (United States)

    Mizuhara, Tsukasa; Oishi, Shinya; Ohno, Hiroaki; Shimura, Kazuya; Matsuoka, Masao; Fujii, Nobutaka

    2012-11-01

    3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine (PD 404182) is an antiretroviral agent with submicromolar inhibitory activity against human immunodeficiency virus-1 (HIV-1) and HIV-2 infection. In the current study, the structure-activity relationships of accessory groups at the 3- and 9-positions of pyrimido[1,2-c][1,3]benzothiazin-6-imine were investigated for the development of more potent anti-HIV agents. Several different derivatives containing a 9-aryl group were designed and synthesized using Suzuki-Miyaura cross-coupling and Ullmann coupling reactions. Modification of the m-methoxyphenyl or benzo[d][1,3]dioxol-5-yl group resulted in improved anti-HIV activity. In addition, the 2,4-diazaspiro[5.5]undec-2-ene-fused benzo[e][1,3]thiazine derivatives were designed and tested for their anti-HIV activities. The most potent 9-(benzo[d][1,3]dioxol-5-yl) derivative was two-threefold more effective against several strains of HIV-1 and HIV-2 than the parent compound, PD 404182. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Development and Sequential Analysis of a New Multi-Agent, Anti-Acne Formulation Based on Plant-Derived Antimicrobial and Anti-Inflammatory Compounds

    Science.gov (United States)

    Saviuc, Crina; Ciubucă, Bianca; Dincă, Gabriela; Bleotu, Coralia; Drumea, Veronica; Chifiriuc, Mariana-Carmen; Popa, Marcela; Gradisteanu Pircalabioru, Gratiela; Marutescu, Luminita; Lazăr, Veronica

    2017-01-01

    The antibacterial and anti-inflammatory potential of natural, plant-derived compounds has been reported in many studies. Emerging evidence indicates that plant-derived essential oils and/or their major compounds may represent a plausible alternative treatment for acne, a prevalent skin disorder in both adolescent and adult populations. Therefore, the purpose of this study was to develop and subsequently analyze the antimicrobial activity of a new multi-agent, synergic formulation based on plant-derived antimicrobial compounds (i.e., eugenol, β-pinene, eucalyptol, and limonene) and anti-inflammatory agents for potential use in the topical treatment of acne and other skin infections. The optimal antimicrobial combinations selected in this study were eugenol/β-pinene/salicylic acid and eugenol/β-pinene/2-phenoxyethanol/potassium sorbate. The possible mechanisms of action revealed by flow cytometry were cellular permeabilization and inhibition of efflux pumps activity induced by concentrations corresponding to sub-minimal inhibitory (sub-MIC) values. The most active antimicrobial combination represented by salycilic acid/eugenol/β-pinene/2-phenoxyethanol/potassium sorbate was included in a cream base, which demonstrated thermodynamic stability and optimum microbiological characteristics. PMID:28106736

  2. Development and Sequential Analysis of a New Multi-Agent, Anti-Acne Formulation Based on Plant-Derived Antimicrobial and Anti-Inflammatory Compounds

    Directory of Open Access Journals (Sweden)

    Crina Saviuc

    2017-01-01

    Full Text Available The antibacterial and anti-inflammatory potential of natural, plant-derived compounds has been reported in many studies. Emerging evidence indicates that plant-derived essential oils and/or their major compounds may represent a plausible alternative treatment for acne, a prevalent skin disorder in both adolescent and adult populations. Therefore, the purpose of this study was to develop and subsequently analyze the antimicrobial activity of a new multi-agent, synergic formulation based on plant-derived antimicrobial compounds (i.e., eugenol, β-pinene, eucalyptol, and limonene and anti-inflammatory agents for potential use in the topical treatment of acne and other skin infections. The optimal antimicrobial combinations selected in this study were eugenol/β-pinene/salicylic acid and eugenol/β-pinene/2-phenoxyethanol/potassium sorbate. The possible mechanisms of action revealed by flow cytometry were cellular permeabilization and inhibition of efflux pumps activity induced by concentrations corresponding to sub-minimal inhibitory (sub-MIC values. The most active antimicrobial combination represented by salycilic acid/eugenol/β-pinene/2-phenoxyethanol/potassium sorbate was included in a cream base, which demonstrated thermodynamic stability and optimum microbiological characteristics.

  3. Identification of causative organism in cardiac implantable electronic device infections.

    Science.gov (United States)

    Fukunaga, Masato; Goya, Masahiko; Nagashima, Michio; Hiroshima, Kenichi; Yamada, Takashi; An, Yoshimori; Hayashi, Kentaro; Makihara, Yu; Ohe, Masatsugu; Ichihashi, Kei; Ohtsuka, Morimasa; Miyazaki, Hiroaki; Ando, Kenji

    2017-11-01

    The causative organism in cardiovascular implantable electronic device (CIED) infection is usually diagnosed with the cultures from blood, removed leads, and/or infected pocket material. The cultured organism, however, is sometimes different among these samples. Two hundred sixty patients with CIED infection, who underwent lead extraction between April 2005 and December 2014, were analyzed. More than two blood culture sets, all the extracted leads, and swab culture of the pocket were sent to the laboratory for culture. Among the patients all of whose microbiological examinations were available, we analyzed the causative organism defined as the species detected in at least two different sites. All the culture results were available in the 208 patients, showing 69 systemic infections (including 30 cases of infectious endocarditis) and 139 local infections. Blood culture, lead culture, and swab culture were positive in 57 (27%), 169 (81%), and 152 (73%), respectively. Staphylococcus aureus [37% including methicillin-resistant S. aureus (MRSA) (12%)] and coagulase-negative staphylococci (CoNS, 36%) were the most common causative organism, followed by non-staphylococci (23%), and poly-microbial infection (4%). The detection of S. aureus from pocket or removed leads rendered higher predictive value of a causative organism than that of CoNS. The detection of Gram-negative bacteria, fungi, and mycobacteria indicated that it was most likely a causative organism. Gram-positive bacteria excluding Staphylococcus, such as Corynebacterium spp., tended to coexist as a benign organism. The causative organism is mostly S. aureus and CoNS. Detection of S. aureus or Gram-negative bacteria means that it is more likely a causative organism. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  4. New tricks for an old natural product: discovery of highly potent evodiamine derivatives as novel antitumor agents by systemic structure-activity relationship analysis and biological evaluations.

    Science.gov (United States)

    Dong, Guoqiang; Wang, Shengzheng; Miao, Zhenyuan; Yao, Jianzhong; Zhang, Yongqiang; Guo, Zizhao; Zhang, Wannian; Sheng, Chunquan

    2012-09-13

    Evodiamine is a quinazolinocarboline alkaloid isolated from the fruits of traditional Chinese herb Evodiae fructus . Previously, we identified N13-substituted evodiamine derivatives as potent topoisomerase I inhibitors by structure-based virtual screening and lead optimization. Herein, a library of novel evodiamine derivatives bearing various substitutions or modified scaffold were synthesized. Among them, a number of evodiamine derivatives showed substantial increase of the antitumor activity, with GI(50) values lower than 3 nM. Moreover, these highly potent compounds can effectively induce the apoptosis of A549 cells. Interestingly, further computational target prediction calculations in combination with biological assays confirmed that the evodiamine derivatives acted by dual inhibition of topoisomerases I and II. Moreover, several hydroxyl derivatives, such as 10-hydroxyl evodiamine (10j) and 3-amino-10-hydroxyl evodiamine (18g), also showed good in vivo antitumor efficacy and low toxicity at the dose of 1 mg/kg or 2 mg/kg. They represent promising candidates for the development of novel antitumor agents.

  5. A General Synthetic Procedure for 2-chloromethyl-4(3H-quinazolinone Derivatives and Their Utilization in the Preparation of Novel Anticancer Agents with 4-Anilinoquinazoline Scaffolds

    Directory of Open Access Journals (Sweden)

    Ying-Lan Zhao

    2010-12-01

    Full Text Available In our ongoing research on novel anticancer agents with 4-anilinoquinazoline scaffolds, a series of novel 2-chloromethyl-4(3H-quinazolinones were needed as key intermediates. An improved one-step synthesis of 2-chloromethyl-4(3H-quinazolinones utilizing o-anthranilic acids as starting materials was described. Based on it, 2-hydroxy-methyl-4(3H-quinazolinones were conveniently prepared in one pot. Moreover, two novel 4-anilinoquinazoline derivatives substituted with chloromethyl groups at the 2-position were synthesized and showed promising anticancer activity in vitro.

  6. Binding of transition metal ions [cobalt, copper, nickel and zinc] with furanyl-, thiophenyl-, pyrrolyl-, salicylyl- and pyridyl-derived cephalexins as potent antibacterial agents.

    Science.gov (United States)

    Chohan, Zahid H; Pervez, Humayun; Khan, Khalid Mohammed; Rauf, A; Supuran, Claudiu T

    2004-02-01

    A method is described for the preparation of novel cephalexin-derived furanyl-, thiophenyl-, pyrrolyl-, salicylyl- and pyridyl-containing compounds showing potent antibacterial activity. The binding of these newly synthesized antibacterial agents with metal ions such as cobalt(II), copper(II), nickel(II) and zinc(II) has been studied and their inhibitory properties against various bacterial species such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae are also reported. These results suggest that metal ions to possess an important role in the designing of metal-based antibacterials and that such complexes are more effective against infectious diseases compared to the uncomplexed drugs.

  7. Anti-cancer agents based on 4-(hetero)Ary1-1,2,5-oxadiazol-3-yl Amino derivatives and a method of making

    Science.gov (United States)

    Gakh, Andrei A.; Krasavin, Mikhail; Karapetian, Ruben; Rufanov, Konstantin A.; Konstantinov, Igor; Godovykh, Elena; Soldatkina, Olga; Sosnov, Andrey V.

    2013-01-29

    The present disclosure relates to novel compounds that can be used as anti-cancer agents in the prostate cancer therapy. ##STR00001## In particular, the invention relates N-substituted derivatives of 4-(hetero)aryl-1,2,5-oxadiazol-3-yl amines having the structural Formula (I) and (II), stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof. Meaning of R1 and R2 in the Formula (I) and (II) are defined in claim 1. The invention also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  8. SYNTHESIS AND CHARACTERIZATION OF SOME NOVEL β LACTAM CONDENSED BIOACTIVE 2-AZETIDINONE DERIVATIVES AS PROSPECTIVE ANTIMICROBIAL AGENT

    Directory of Open Access Journals (Sweden)

    Maity S.

    2012-04-01

    Full Text Available It is worthwhile to synthesize some novel series of β- lactam, 2-azetidinone derivatives carrying quinoline moiety. Structures of these 2-azetidinone derivatives have been characterized by spectral data like IR, 1HNMR & Mass spectroscopy. Compounds 4a,4b,4f,4g and 4h has been found extremely significant anti bacterial activity against four different strains like Staphylococcus aureus (NCIM 2079, Bacillus subtilius (NCIM 2708, Pseudomonas aeruginosa (NCIM 2242 and Escherichia coli (NCIM 2685 as compared to ampicillin antibiotic, while compound 4f was found extremely significant antifungal activity against Candida albicans(NCIM 22491 as compared to griseofulvin.

  9. Hierarchy, causation and explanation: ubiquity, locality and pluralism.

    Science.gov (United States)

    Love, Alan C

    2012-02-06

    The ubiquity of top-down causal explanations within and across the sciences is prima facie evidence for the existence of top-down causation. Much debate has been focused on whether top-down causation is coherent or in conflict with reductionism. Less attention has been given to the question of whether these representations of hierarchical relations pick out a single, common hierarchy. A negative answer to this question undermines a commonplace view that the world is divided into stratified 'levels' of organization and suggests that attributions of causal responsibility in different hierarchical representations may not have a meaningful basis for comparison. Representations used in top-down and bottom-up explanations are primarily 'local' and tied to distinct domains of science, illustrated here by protein structure and folding. This locality suggests that no single metaphysical account of hierarchy for causal relations to obtain within emerges from the epistemology of scientific explanation. Instead, a pluralist perspective is recommended-many different kinds of top-down causation (explanation) can exist alongside many different kinds of bottom-up causation (explanation). Pluralism makes plausible why different senses of top-down causation can be coherent and not in conflict with reductionism, thereby illustrating a productive interface between philosophical analysis and scientific inquiry.

  10. Design and synthesis of 3,4-methylenedioxy-6-nitrophenoxyacetylhydrazone derivatives obtained from natural safrole: new lead-agents with analgesic and antipyretic properties.

    Science.gov (United States)

    Bezerra-Netto, Heleno J C; Lacerda, Daniel I; Miranda, Ana Luisa P; Alves, Hélio M; Barreiro, Eliezer J; Fraga, Carlos A M

    2006-12-01

    In this work, we reported the synthesis and evaluation of the analgesic, anti-inflammatory, and antipyretic properties of new 2-(6-nitro-benzo[1,3]dioxol-5-yloxy)-acetylhydrazone derivatives (3), designed exploring molecular hybridization and isosteric replacement approaches between nimesulide (1) and carbanalogue NAH series (2) developed at LASSBio. Target compounds were synthesized in very good yields exploiting abundant Brazilian natural product safrole (4) as starting material. The evaluation of the antinociceptive properties of this series led us to discover a new potent prototype of analgesic and antipyretic agent, that is, NAH derivative 3c, named LASSBio-891, which showed to be more potent than dipyrone used as standard.

  11. Synthesis of some novel pyrazolo[3,4-d] pyrimidin-4(5H-one derivatives as potential antimicrobial agent

    Directory of Open Access Journals (Sweden)

    Dipen K Sureja

    2016-01-01

    Full Text Available Objectives: The aim of the present work was to synthesize a novel series of pyrazolo[3,4-d]pyrimidin-4(5H-one derivatives and evaluate their in vitro antimicrobial activity. Methods: Cyclization of an ortho-amino ester of 1-(2,4-dinitrophenylpyrazole with various aliphatic/aromatic nitriles under different reaction conditions such as conventional and microwave assisted synthesis, provided pyrazolo[3,4-d] pyrimidin-4(5H-one derivatives. All the synthesized compounds were evaluated in vitro for their antimicrobial activity against selected bacteria and fungi by agar well diffusion method. Results: All newly synthesized compounds were characterized using spectral and elemental analysis. Compounds 2e, 2f, and 2g showed significant antimicrobial activity as compared to standard drugs used. Conclusion: The newly synthesized compounds could be useful templates for the design and optimization of more active analogs as a possible antimicrobial agent.

  12. Natural products-based insecticidal agents 11. Synthesis and insecticidal activity of novel 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxin derivatives against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Xu, Hui; Zhang, Jun-Liang

    2011-09-15

    In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, 14 novel 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxin derivatives were stereoselectively semisynthesized from podophyllotoxin, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo. Especially compounds 9c' and 9g' exhibited the most promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach at 1mg/mL. Generally, it was preliminarily demonstrated that arylsulfonyloxy groups at the C-2 position of benzyloxy moiety and the length of the side chain on the benzenesulfonyloxy group of 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxins might be important for the insecticidal activity.

  13. Natural-product-based insecticidal agents 14. Semisynthesis and insecticidal activity of new piperine-based hydrazone derivatives against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Qu, Huan; Yu, Xiang; Zhi, Xiaoyan; Lv, Min; Xu, Hui

    2013-10-15

    In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, twenty-six new piperine-based hydrazone derivatives were synthesized from piperine, an alkaloid isolated from Piper nigrum Linn. The single-crystal structures of 6c, 6q and 6w were unambiguously confirmed by X-ray crystallography. Their insecticidal activity was evaluated against the pre-third-instar larvae of Mythimna separata Walker in vivo. Especially compounds 6b, 6i and 6r, the final mortality rates of which, at the concentration of 1 mg/mL, were 62.1%, 65.5% and 65.5%, respectively, exhibited more pronounced insecticidal activity compared to toosendanin at 1 mg/mL, a commercial botanical insecticide isolated from Melia azedarach. It suggested that introduction of the substituents at the C-2 position on the phenyl ring of the hydrazone derivatives was important for their insecticidal activity.

  14. Natural products-based insecticidal agents 9. Design, semisynthesis and insecticidal activity of 28-acyloxy derivatives of toosendanin against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Xu, Hui; Zhang, Jun-Liang

    2011-04-01

    In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, twelve 28-acyloxy derivatives of toosendanin (2a-l) were semisynthesized and preliminarily evaluated their activity against the pre-third-instar larvae of Mythimna separata Walker in vivo at the concentration of 1mg/mL. Some compounds exhibited the potent insecticidal activity. Especially compounds 2c and 2j displayed the more promising insecticidal activity than their natural precursor, toosendanin, a commercial insecticide derived from Melia azedarach at 1mg/mL. In general, it indicated that the butanoyloxy or phenylacryloyloxy moiety at the 28-position of toosendanin was essential for the insecticidal activity.

  15. N-Phenyl-2-p-tolylthiazole-4-carboxamide derivatives: Syn-thesis and cytotoxicity evaluation as anticancer agents

    Directory of Open Access Journals (Sweden)

    Ahmad Mohammadi-Farani

    2014-07-01

    Conclusion: A new series of phenylthiazole derivatives were synthesized and their anticancer activity was assessed against cancerous cell lines. More structural modifications and derivatization is necessary to achieve to the more potent compounds.       

  16. Synthesis, Biological Evaluation and Structure-Activity Relationships of New Quinoxaline Derivatives as Anti-Plasmodium falciparum Agents

    Directory of Open Access Journals (Sweden)

    Ana Gil

    2014-02-01

    Full Text Available We report the synthesis and antimalarial activities of eighteen quinoxaline and quinoxaline 1,4-di-N-oxide derivatives, eight of which are completely novel. Compounds 1a and 2a were the most active against Plasmodium falciparum strains. Structure-activity relationships demonstrated the importance of an enone moiety linked to the quinoxaline ring.

  17. Synthesis, biological evaluation and structure-activity relationships of new quinoxaline derivatives as anti-Plasmodium falciparum agents.

    Science.gov (United States)

    Gil, Ana; Pabón, Adriana; Galiano, Silvia; Burguete, Asunción; Pérez-Silanes, Silvia; Deharo, Eric; Monge, Antonio; Aldana, Ignacio

    2014-02-18

    We report the synthesis and antimalarial activities of eighteen quinoxaline and quinoxaline 1,4-di-N-oxide derivatives, eight of which are completely novel. Compounds 1a and 2a were the most active against Plasmodium falciparum strains. Structure-activity relationships demonstrated the importance of an enone moiety linked to the quinoxaline ring.

  18. Synthesis, Biological Evaluation and Structure-Activity Relationships of New Quinoxaline Derivatives as Anti-Plasmodium falciparum Agents

    OpenAIRE

    Ana Gil; Adriana Pabón; Silvia Galiano; Asunción Burguete; Silvia Pérez-Silanes; Eric Deharo; Antonio Monge; Ignacio Aldana

    2014-01-01

    We report the synthesis and antimalarial activities of eighteen quinoxaline and quinoxaline 1,4-di-N-oxide derivatives, eight of which are completely novel. Compounds 1a and 2a were the most active against Plasmodium falciparum strains. Structure-activity relationships demonstrated the importance of an enone moiety linked to the quinoxaline ring.

  19. Molecular identification of a causative parasite species using formalin-fixed paraffin embedded (FFPE) tissues of a complicated human pulmonary sparganosis case without decisive clinical diagnosis.

    Science.gov (United States)

    Koonmee, Supinda; Intapan, Pewpan M; Yamasaki, Hiroshi; Sugiyama, Hiromu; Muto, Maki; Kuramochi, Toshiaki; Kularbkeaw, Jurairat; Kanpittaya, Jaturat; Maleewong, Wanchai; Nawa, Yukifumi

    2011-12-01

    PCR-based molecular diagnosis was made for the identification of causative agents of the clinically suspected pulmonary proliferative sparganosis case found in Thailand using formalin-fixed paraffin-embedded (FFPE) biopsy specimens. As a reference, FFPE biopsy specimen from a typical cutaneous sparganosis case was examined together. DNA samples were extracted from tissues and two partial fragments of cytochrome c oxidase subunit 1 (cox1) gene were amplified for the detection of Spirometra DNA. Two cox1 fragments were amplified successfully for both specimens. After alignment of nucleotide sequences of the PCR-amplicons, the causative agents of both cases were identified as Spirometra erinaceieuropaei.

  20. Antileishmanial Activity of the Hydroalcoholic Extract of Miconia langsdorffii, Isolated Compounds, and Semi-Synthetic Derivatives

    Directory of Open Access Journals (Sweden)

    Wilson R. Cunha

    2011-02-01

    Full Text Available The in vitro activity of the crude hydroalcoholic extract of the aerial parts of Miconia langsdorffii Cogn. was evaluated against the promastigote forms of L. amazonensis, the causative agent of cutaneous leishmaniasis in humans. The bioassay-guided fractionation of this extract led to identification of the triterpenes ursolic acid and oleanolic acid as the major compounds in the fraction that displayed the highest activity. Several ursolic acid semi-synthetic derivatives were prepared, to find out whether more active compounds could be obtained. Among these ursolic acid-derived substances, the C-28 methyl ester derivative exhibited the best antileishmanial activity.

  1. Novel Benzothiazole, Benzimidazole and Benzoxazole Derivatives as Potential Antitumor Agents: Synthesis and Preliminary in Vitro Biological Evaluation

    Directory of Open Access Journals (Sweden)

    Li Yang

    2012-01-01

    Full Text Available In a previous hit-to-lead research program targeting anticancer agents, two promising lead compounds, 1a and 1b, were found. However, the poor solubility of 1a and 1b made difficult further in vivo studies. To solve this problem, a lead optimization was conducted through introducing N-methyl-piperazine groups at the 2-position and 6-position. To our delight, the optimized analogue 1d showed comparable antiproliferative activity in vitro with better solubility, compared with 1a. Based on this result, the replacement of the benzothiazole scaffold with benzimidazole and benzoxazole moieties afforded 1f and 1g, whose activities were fundamentally retained. In the preliminary in vitro biological evaluation, the immunofluorescence staining of HCT116 cells indicated that 1d, 1f and 1g led to cytosolic vacuolization which was not induced by 1a at low micromolecular concentrations. These results suggest that these optimized compounds might potentially constitute a novel class of anticancer agents, which merit further studies.

  2. Novel benzothiazole, benzimidazole and benzoxazole derivatives as potential antitumor agents: synthesis and preliminary in vitro biological evaluation.

    Science.gov (United States)

    Xiang, Pu; Zhou, Tian; Wang, Liang; Sun, Chang-Yan; Hu, Jing; Zhao, Ying-Lan; Yang, Li

    2012-01-17

    In a previous hit-to-lead research program targeting anticancer agents, two promising lead compounds, 1a and 1b, were found. However, the poor solubility of 1a and 1b made difficult further in vivo studies. To solve this problem, a lead optimization was conducted through introducing N-methyl-piperazine groups at the 2-position and 6-position. To our delight, the optimized analogue 1d showed comparable antiproliferative activity in vitro with better solubility, compared with 1a. Based on this result, the replacement of the benzothiazole scaffold with benzimidazole and benzoxazole moieties afforded 1f and 1g, whose activities were fundamentally retained. In the preliminary in vitro biological evaluation, the immunofluorescence staining of HCT116 cells indicated that 1d, 1f and 1g led to cytosolic vacuolization which was not induced by 1a at low micromolecular concentrations. These results suggest that these optimized compounds might potentially constitute a novel class of anticancer agents, which merit further studies.

  3. Event ontology in quantum mechanics and downward causation

    CERN Document Server

    Gambini, Rodolfo

    2016-01-01

    We show that several interpretations of quantum mechanics admit an ontology of objects and events. This ontology reduces the breach between mind and matter. When humans act, their actions do not appear explainable in mechanical terms but through mental activity: motives, desires or needs that propel them to action. These are examples of what in the last few decades have come to be called "downward causation". Basically, downward causation is present when the disposition of the whole to behave in a certain way cannot be predicted from the dispositions of the parts. The event ontology of quantum mechanics allow us to show that systems in entangled states present emergent new properties and downward causation.

  4. Backward Causation, Isolation and the Pursuit of Justice

    CERN Document Server

    Cirkovic, M M; Cirkovic, Milan M.; Cveticanin, Suzana

    2001-01-01

    The recent operationalization of the famous Newcomb's game by Schmidt (1998) offers an interesting and thought-provoking look at the plausibility of backward causation in a Newtonian universe. Hereby we investigate two details of the Schmidt's scenario which may, at least in principle, invalidate his conclusion in two different domains: one dealing with the issue of Newtonian predictability in specific instance of human actions, and the other stemming from a possible strategy aimed at obviating the anthropically oriented view of backward causation as applied to a judicial and ethical problem posed by a version of the scenario. We conclude that the scenario is at least to be more complex than originally presented in order to remain viable. However, it points to a very deep and delicate question of compatibility of backward causation with the conventional ethical standards.

  5. Intercellular imaging by a polyarginine derived cell penetrating peptide labeled magnetic resonance contrast agent,diethylenetriamine pentaacetic acid gadolinium

    Institute of Scientific and Technical Information of China (English)

    GUO You-min; LIU Min; YANG Jun-le; GUO Xiao-juan; WANG Si-cen; DUAN Xiao-yi; WANG Peng

    2007-01-01

    Background The cellular plasma membrane represents a natural barrier to many exogenous molecules including magnetic resonance (MR) contrast agent. Cell penetrating peptide (CPP) is used to internalize proteins, peptides, and radionuclide. This study was undertaken to assess the value of a new intracellular MR contrast medium, CPP labeled diethylenetriamine pentaacetic acid gadolinium (Gd-DTPA) in molecular imaging in vitro. Methods Fluorescein-5-isothiocyanate (FITC) and Gd-DTPA respectively labeled with CPP (FITC-CPP, Gd-DTPA-CPP) were synthesized by the solid-phase method. Human hepatic cancer cell line-HepG2 was respectively stained by FITC-CPP and FITC to observe the uptake and intracellular distribution. HepG2 was respectively incubated with 100 nmol/ml Gd-DTPA-CPP for 0, 10, 30, 60 minutes, and imaged by MR for studying the relationship between the incubation time and T1WI signal. The cytotoxicity to NIH3T3 fibroblasts cells was measured by 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide reduction assay (MTT). Results The molecular weights of CPP labeled imaging agents, which were determined by MALDI mass spectrometry (FITC-CPP MW=2163.34, Gd-DTPA-CPP MW=2285.99), were similar to the calculated molecular weights. Confocal microscopy suggested HepG2 translocated FITC-CPP in cytoplasm and nucleus independent with the incubation temperature. MR images showed HepG2 uptaken Gd-DTPA-CPP had a higher T1 weighted imaging (T1WI) signal, and that the T1WI signal intensity was increasing in a time-dependent manner (r=0.972, P=0.001), while the signal intensity between the cells incubated by Gd-DTPA for 60 minutes and the controlled cells was not significantly different (P=0.225). By MTT, all concentrations from 50 nmol/ml to 200 nmol/ml had no significant (F=0.006, P=1.000) effect on cell viability of mouse NIH3T3 fibroblasts, compared with the control group. Conclusions The newly constructed CPP based on polyarginine can translocate cells by carrying FITC

  6. 3D-QSAR analysis of a series of S-DABO derivatives as anti-HIV agents by CoMFA and CoMSIA.

    Science.gov (United States)

    Xu, H R; Fu, L; Zhan, P; Liu, X Y

    2016-12-01

    In this study, we retrieved a series of 59 dihydroalkylthio-benzyloxopyrimidine (S-DABO) derivatives, which is a class of highly potent HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs) reported from published articles, and analysed them with comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). Statistically significant three-dimensional quantitative structure-activity relationship (3D-QSAR) models by CoMFA and CoMSIA were derived from a training set of 46 compounds on the basis of the rigid body alignment. Further, the predictive ability of the QSAR models was validated by a test set of 13 compounds. Based on the information derived from CoMFA and CoMSIA contour maps, we have identified some steric and electrostatic features for improving the activities of these inhibitors, and we validated the 3D-QSAR results by a molecular docking method. On the basis of the obtained results, we designed a new series of S-DABO derivatives with high activities. Therefore, this study could be utilized to design more potent S-DABO analogues as anti-HIV agents.

  7. Novel Steroidal (6R)-Spiro-1,3,4-thiadiazoline Derivatives as Anti-bacterial Agents

    Institute of Scientific and Technical Information of China (English)

    Khan Salman A.; Asiri, Abdullah M.

    2012-01-01

    Novel steroidal (6R)-spiro-1,3,4-thiadiazoline derivatives have been synthesized by the cyclization of steroidal thiosemiearbazones. Thiosemicarbazones have been synthesized by the reaction of steroidal ketones with thiosemi- carbazide. All the compounds have been characterized by IR, 1H NMR, mass and elemental analyses. The antibacterial activities of these compounds have been first tested in vitro by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC) values have been determined with the reference of standard drug amoxicillin. The results showed that steroidal thiadiazoline de- rivatives exhibited better antibacterial activity than the steroidal thiosemicarbazone derivatives. Chloro and acetoxy substituents on the 3β-position of the steroidal thiadiazoline ring increased the anti-bacterial activity. Among all the compounds, compounds 7 and 8 were found better inhibitors as compared to the respective drug amoxicillin.

  8. Design, synthesis, and structure-activity relationship studies of novel thioether pleuromutilin derivatives as potent antibacterial agents.

    Science.gov (United States)

    Ling, Chenyu; Fu, Liqiang; Gao, Suo; Chu, Wenjing; Wang, Hui; Huang, Yanqin; Chen, Xiaoyan; Yang, Yushe

    2014-06-12

    A series of novel thioether pleuromutilin derivatives incorporating various heteroaromatic substituents into the C14 side chain have been reported. Structure-activity relationship (SAR) studies resulted in compounds 52 and 55 with the most potent in vitro antibacterial activity among the series (MIC = 0.031-0.063 μg/mL). Further optimization to overcome the poor water solubility of compound 55 resulted in compounds 87, 91, 109, and 110 possessing good in vitro antibacterial activity with increased hydrophilicity. Compound 114, the water-soluble phosphate prodrug of compound 52, was also prepared and evaluated. Among the derivatives, compound 110 showed moderate pharmacokinetic profiles and good in vivo efficacy in both MSSA and MRSA systemic infection models. Compound 110 was further evaluated in CYP450 inhibition assay and displayed intermediate in vitro inhibition of CYP3A4.

  9. In Silico Studies of Quinoxaline-2-Carboxamide 1,4-di-N-Oxide Derivatives as Antimycobacterial Agents

    Directory of Open Access Journals (Sweden)

    Awwad A. Radwan

    2014-02-01

    Full Text Available Molecular modelling studies were performed on some previously reported novel quinoxaline-2-carboxamide 1,4-di-N-oxide derivatives (series 1–9. Using the LigandScout program, a pharmacophore model was developed to further optimize the antimycobacterial activity of this series of compounds. Using the Dock6 program, docking studies were performed in order to investigate the mode of binding of these compounds. The molecular modeling study allowed us to confirm the preferential binding mode of these quinoxaline-2-carboxamide 1,4-di-N-oxide derivatives inside the active site. The obtained binding mode was as same as that of the novobiocin X-ray structure.

  10. Design and synthesis of Quinazolinone, Benzothiazole derivatives bearing guanidinopropanoic acid moiety and their Schiff bases as cytotoxic and antimicrobial agents

    Directory of Open Access Journals (Sweden)

    Palani Venkatesh

    2016-09-01

    Full Text Available Two series of Benzothiazole, Quinazolinone derivatives bearing guanidinopropanoic acid (38 compounds including 27 intermediates and one series of Schiff base derivatives (14 compounds were synthesized, characterized then evaluated for their cytotoxicity against human cervix cell line (HeLa by MTT assay; antimicrobial activity against 11 pathogenic bacteria, 10 pathogenic fungus using standard of ciprofloxacin and Clotrimazole respectively. Compounds 13–18 showed significant activity against HeLa with IC50 range of 2–550 μM. Compound 3-(3-(6-hydroxybenzo[d]thiazol-2-ylguanidinopropanoic acid (18 showed potent activity against human HeLa cell line with the half maximal inhibitory concentration (IC50 values of 1.8 μM which was close to the value of the positive control, doxorubicin. Antimicrobial result indicated that, compounds showed differential activity against the tested fungus and bacteria. Compounds 11, 14, 38 and 49 exhibited potent antibacterial and antifungal activity.

  11. Synthesis of New Fluorine Substituted Heterocyclic Nitrogen Systems Derived from p-Aminosalicylic Acid as Antimycobacterial Agents

    Directory of Open Access Journals (Sweden)

    Mohammed Saleh I. T. Makki

    2013-01-01

    Full Text Available Some new fluorine substituted heterocyclic nitrogen systems 2–17 have been synthesized from ring closure reactions of substituted p-amino salicylic acids (PAS. The Schiffs base of PAS was cyclized with chloroacetyl chloride and mercaptoacetic acid to give azetidinone 2, thiazolidinone 3, and spiro-fluoroindolothiazoline-dione 10. However, PAS when reacted directly with 4-fluorobenzoyl chloride and 5-oxazolinone yielded derivatives 4, 5, and 7. Aminomethylation of PAS using formaldehyde and piperidine or piperazine formed N-alkyl and N,N′-dialkyl derivatives (11 and 12 respectively upon fluorinated benzoylation gave compounds 13 and 14. Similarly, treatment of PAS with thiosemicarbazide 15 and subsequent cyclization with diethyl oxalate yielded the fluorinated heterocycle 17. The structures of the fluorinated heterocyclic systems have been established on the basis of elemental analysis, 1H NMR, 13C NMR, and MS spectral data. Some of the targets exhibited a high inhibition towards Mycobacterium strain with favorable log P values.

  12. Synthesis and Biological Evaluation of N- Pyrazolyl Derivatives and Pyrazolopyrimidine Bearing a Biologically Active Sulfonamide Moiety as Potential Antimicrobial Agent

    Directory of Open Access Journals (Sweden)

    Hend N. Hafez

    2016-08-01

    Full Text Available A series of novel pyrazole-5-carboxylate containing N-triazole derivatives 3,4; different heterocyclic amines 7a–b and 10a–b; pyrazolo[4,3-d]pyrimidine containing sulfa drugs 14a,b; and oxypyrazolo[4,3-d]pyrimidine derivatives 17, 19, 21 has been synthesized. The structure of the newly synthesized compounds was elucidated on the basis of analytical and spectral analyses. All compounds have been screened for their in vitro antimicrobial activity against three gram-positive and gram-negative bacteria as well as three fungi. The results revealed that compounds 14b and 17 had more potent antibacterial activity against all bacterial strains than reference drug Cefotaxime. Moreover compounds 4, 7b, and 12b showed excellent antifungal activities against Aspergillus niger and Candida albicans in low inhibitory concentrations but slightly less than the reference drug miconazole against Aspergillus flavus.

  13. A Series of New Ligustrazine-Triterpenes Derivatives as Anti-Tumor Agents: Design, Synthesis, and Biological Evaluation.

    Science.gov (United States)

    Xu, Bing; Chu, Fuhao; Zhang, Yuzhong; Wang, Xiaobo; Li, Qiang; Liu, Wei; Xu, Xin; Xing, Yanyi; Chen, Jing; Wang, Penglong; Lei, Haimin

    2015-09-02

    A series of novel ligustrazine-triterpenes derivatives was designed, synthesized and screened for their cytotoxicity against five cancer cell lines (Bel-7402, HepG2, HT-29, Hela, and MCF-7) and Madin-Darby canine kidney (MDCK). Current study suggested that most of the ligustrazine-triterpenes conjunctions showed better cytotoxicity than the starting materials. In particular, compound 4a exhibited better cytotoxic activity (IC5020 μM) towards MDCK cells. A combination of fluorescence staining observation and flow cytometric analysis indicated that 4a could induce HepG2 cell apoptosis. Further studies suggested that 4a-induced apoptosis is mediated through depolarization of the mitochondrial membrane potential and increase of intracellular free Ca2+ concentration. In addition, the structure-activity relationships of these derivatives were briefly discussed.

  14. Quantitative Structure-Activity Relationship Analysis of Xanthone Derivates as Cytotoxic Agents in Liver Cancer Cell Line HepG2

    Directory of Open Access Journals (Sweden)

    Isnatin Miladiyah

    2016-05-01

    Full Text Available The study of xanthone derivatives as cytotoxic agents in cancer is increasing. This study was conducted to explore the Quantitative Structure-Activity Relationship (QSAR of xanthones as cytotoxic agents in HepG2 cells, to find compounds with better potency. The data set were taken from the previous study, involving 26 xanthone derivates and their cytotoxic activities in Inhibitory Concentration 50% (IC50. The parameters (descriptors were obtained from quantum mechanics calculation using semiempirical AM1 method and QSAR models determined with principle component regression, with log (1/IC50 as a dependent variable and five latent variables as independent variables. From the 26 main descriptors, PCR reduced them to five latent variables (1st– 5th LV. The QSAR analysis gave the best model as follows: log (1/IC50 = 4.592 – 0.204 LV1 + 0.295 LV2 + 0.028 LV3 (n = 26, r = 0.571, SE = 0.234, Fcount/Ftable ratio = 1.165, PRESS value = 3.766. The study concluded that the descriptors contributed to anticancer activity were volume, mass, surface area, log P, dipole moment, HOMO energy, LUMO energy, and atomic net charge of some atoms. Modifications of substitution that would contribute to cytotoxic activity can be performed at phenyl ring A and C, but not at B.

  15. {sup 11}C-labeled stilbene derivatives as A{beta}-aggregate-specific PET imaging agents for Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Masahiro; Wilson, Alan; Nobrega, Jose; Westaway, David; Verhoeff, Paul; Zhuang Zhiping; Kung Meiping; Kung, Hank F. E-mail: kunghf@sunmac.spect.upenn.edu

    2003-08-01

    A series of stilbene derivatives as potential diagnostic imaging agents targeting amyloid plaques in Alzheimer's disease (AD) were synthesized and evaluated. The syntheses of the stilbenes were successfully achieved by a simple Wadsworth-Emmons reaction between diethyl (4-nitrobenzyl)phosphonate and 4-methoxybenzaldehyde. 4-N,N-dimethylamino-4'-methyoxy and the corresponding 4-N-monomethylamino-, 4'-hydroxy stilbenes showed good binding affinities towards A{beta} aggregates in vitro (K{sub i} < 10 nM). The {sup 11}C labeled 4-N-methylamino-4'-hydroxystilbene, [{sup 11}C]4, was prepared by {sup 11}C methylation of 4-amino-4'-hydroxystilbene. The [{sup 11}C]4 displayed a moderate lipophilicity (log P = 2.36), and showed a very good brain penetration and washout from normal rat brain after an iv injection. In vitro autoradiography of transgenic AD mouse brain sections showed a high specific labeling of {beta}-amyloid plaques, whereas the control sections showed no binding. Taken together the data suggest that a relatively simple stilbene derivative, [{sup 11}C]4, N-[{sup 11}C]methylamino-4'-hydroxystilbene, may be useful as a positron emission tomography (PET) imaging agent for mapping A{beta} plaques in the brain of patients with Alzheimer's disease.

  16. Synthesis and biological evaluation of one novel technetium-99m-labeled nitroquipazine derivative as an imaging agent for serotonin transporter

    Energy Technology Data Exchange (ETDEWEB)

    Guo Yunhang; Chen Xiangji; Jia Hongmei; Ji Xinmin [Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Liu Boli [Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875 (China)], E-mail: liuboli@bnu.edu.cn

    2008-12-15

    Imaging of serotonin transporter (SERT) by positron emission tomography (PET) or single-photon emission-computed tomography (SPECT) in humans would provide useful information in diagnosis and therapy of several neurodegenerative and neuropsychiatric disorders. 6-Nitroquipazine is a highly potent and selective inhibitor of the SERT. For the development of new {sup 99m}Tc-labeled 6-nitroquipazine derivatives as SERT imaging agents, novel [N-[2-((3-(4-(6-nitroquinolin-2-yl)piperazin-1-yl)propyl)(2-mercaptoethyl) amino]-acetyl-2-aminoethanethiolato] [{sup 99m}Tc]technetium (V) oxide ({sup 99m}Tc-MAMA-3-PQ) and its rhenium analog were synthesized and characterized. {sup 99m}Tc-MAMA-3-PQ displayed high initial brain uptake (0.52% ID/organ at 2 min post-injection (pi)) and relatively fast washout in mice (0.09% ID/organ at 60 min pi). The regional brain distribution studies in rats showed high-specific binding ratios at 60 min pi. Maximum regional contrast ratio observed for thalamus/cerebellum was 2.94, followed by 2.62 for hypothalamus/cerebellum. These encouraging results lead us to further explore its derivatives as new imaging agents for the SERT in the brain.

  17. Synthesis and quantitative structure-activity relationship (QSAR) study of novel 4-acyloxypodophyllotoxin derivatives modified in the A and C rings as insecticidal agents.

    Science.gov (United States)

    He, Shuzhen; Shao, Yonghua; Fan, Lingling; Che, Zhiping; Xu, Hui; Zhi, Xiaoyan; Wang, Juanjuan; Yao, Xiaojun; Qu, Huan

    2013-01-23

    In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, we have synthesized three series of novel 4-acyloxy compounds derived from podophyllotoxin modified in the A and C rings, which is isolated as the main secondary metabolite from the roots and rhizomes of Podophyllum hexandrum . Their insecticidal activity was preliminarily evaluated against the pre-third-instar larvae of Mythimna separata in vivo. Compound 9g displayed the best promising insecticidal activity. It revealed that cleavage of the 6,7-methylenedioxy group of podophyllotoxin will lead to a less active compound and that the C-4 position of podophyllotoxin was the important modification location. A quantitative structure-activity relationship (QSAR) model was developed by genetic algorithm combined with multiple linear regression (GA-MLR). For this model, the squared correlation coefficient (R(2)) is 0.914, the leave-one-out cross-validation correlation coefficient (Q(2)(LOO)) is 0.881, and the root-mean-square error (RMSE) is 0.024. Five descriptors, BEHm2, Mor14v, Wap, G1v, and RDF020e, are likely to influence the biological activity of these compounds. Among them, two important ones are BEHm2 and Mor14v. This study will pave the way for further design, structural modification, and development of podophyllotoxin derivatives as insecticidal agents.

  18. Synthesis, biological evaluation and structure-activity relationships of new quinoxaline derivatives as anti-Plasmodium falciparum agents

    OpenAIRE

    Gil, Ana Gloria; Pabón, Adriana; Galiano, Silvia; Burguete, M. Isabel; Pérez-Silanes, Silvia; Deharo, Eric; Monge, Antonio; Aldana Ignacio

    2014-01-01

    We report the synthesis and antimalarial activities of eighteen quinoxaline and quinoxaline 1,4-di-N-oxide derivatives, eight of which are completely novel. Compounds 1a and 2a were the most active against Plasmodium falciparum strains. Structure-activity relationships demonstrated the importance of an enone moiety linked to the quinoxaline ring. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

  19. Synthesis, Characterization and Biological Evaluation of Some Quinoxaline Derivatives: A Promising and Potent New Class of Antitumor and Antimicrobial Agents

    OpenAIRE

    Al-Marhabi, Aisha; Abbas, Hebat-Allah; Ammar, Yousry

    2015-01-01

    the present work deals with the synthesis of some novel tetrazolo[1,5-a]quinoxalines, N-pyrazoloquinoxalines, the corresponding Schiff bases, 1,2,4-triazinoquinoxalines and 1,2,4-triazoloquinoxalines. These compounds were synthesized via the reaction of the key intermediate hydrazinoquinoxalines with various reagents and evaluated for anticancer and antimicrobial activity. The results indicated that tetrazolo[1,5-a]quinoxaline derivatives showed the best result, with the highest inhibitory ef...

  20. Targeting some THTT derivatives as scaffold for dopamine to CNS, neuroprotective agents, computation and docking on GSK-3

    Directory of Open Access Journals (Sweden)

    Abdel-Nasser El-Shorbagi

    2014-08-01

    Full Text Available Enhanced delivery to central nervous system (CNS was studied by application of the biolabile carrier-linked; tetrahydro-thiadiazinethione (THTT system. The delivery method which relies on biochemical liberation of the investigated compound; p-hydroxy phenethyl amine required synthetic derivatization to increase its lipophilicity and to resist its degradation by mono amine oxidase (MAO in plasma. p-Hydroxyphenethyl amine as a possible precursor of dopamine that centrally controls Parkinson's disease (PD was incorporated in tetrahydro-2H-1,3,5- thiadiazine-2-thione (THTT skeleton. Derivatives (7a-d were prepared and found to be a promising lipophilic carriers to pass blood brain barrier (BBB. The compounds were in vivo investigated, and all derivatives successfully passed BBB. The steps of the reaction to provide the title compounds are clarified in the experimental part. The structures were elucidated by spectral data. Some reported THTT derivatives, as well as 7a-c were docked with glycogen synthase kinase 3-beta (GSK-3β. The latter 7a-c bacuase of their high docking scores, are statistically studied. Doses of some potent compounds with the docking and computational data of their structures were also done and an equation was obtained allowing more oriented drug discovery approaches.

  1. Synthesis and Pharmacological Screening of Several Aroyl and Heteroaroyl Selenylacetic Acid Derivatives as Cytotoxic and Antiproliferative Agents

    Directory of Open Access Journals (Sweden)

    Carmen Sanmartín

    2009-09-01

    Full Text Available The synthesis and cytotoxic activity of a series of twenty six aroyl and heteroaroyl selenylacetic acid derivatives of general formula Ar-CO-Se-CH2-COOH or Heterar-CO-Se-CH2-COOH are reported. The synthesis was carried out by reaction of acyl chlorides with sodium hydrogen selenide, prepared in situ, and this led to the formation of sodium aroylselenides that subsequently reacted with α-bromoacetic acid to produce the corresponding selenylacetic acid derivatives. All of the compounds were tested against a prostate cancer cell line (PC-3 and some of the more active compounds were assessed against a panel of four human cancer cell lines (CCRF-CEM, HTB-54, HT-29, MCF-7 and one mammary gland-derived non-malignant cell line (184B5. Some of the compounds exhibited remarkable cytotoxic and antiproliferative activities against MCF-7 and PC-3 that were higher than those of the reference compounds doxorubicin and etoposide, respectively. For example, in MCF-7 when Ar = phenyl, 3,5-dimethoxyphenyl or benzyl the TGI values were 3.69, 4.18 and 6.19 μM. On the other hand, in PC-3 these compounds showed values of 6.8, 4.0 and 2.9 μM. Furthermore, benzoylselenylacetic acid did not provoke apoptosis nor did it perturb the cell cycle in MCF-7.

  2. Synthesis of new quinoxaline-2-carboxylate 1,4-dioxide derivatives as anti-Mycobacterium tuberculosis agents.

    Science.gov (United States)

    Jaso, Andrés; Zarranz, Belén; Aldana, Ignacio; Monge, Antonio

    2005-03-24

    Twenty-nine new 6(7)-substituted quinoxaline-2-carboxylate 1,4-dioxide derivatives were synthesized and evaluated for in vitro antituberculosis activity. In general, the in vitro activity is significantly affected by substituents on the quinoxaline nucleus. It has been observed that the presence of a chloro, methyl, or methoxy group in position 7 of the benzene moiety reduces the MIC and IC(50) values. However, antituberculosis activity principally depends on the substituents in the carboxylate group, improving in the following order: benzyl > ethyl > 2-methoxyethyl > allyl > tert-butyl. Fourteen compounds have been selected for macrophage assay, and the results show that ethyl and benzyl 3-methylquinoxaline-2-carboxylate 1,4-dioxide derivatives with the chlorine group in position 7 of the benzene moiety (compounds 10 and 26) and the unsubstituted derivatives (compounds 11 and 27) have good antitubercular activity, including activity in macrophages. In addition, compounds 7 and 28 (the only ones tested up to now) are active against drug-resistant strains of M. tuberculosis H(37)Rv. In conclusion, the potency, selectivity, and low cytotoxicity of these compounds make them valid leads for synthesizing new compounds that possess better activity.

  3. Antitumor Activity of Artemisinin and Its Derivatives: From a Well-Known Antimalarial Agent to a Potential Anticancer Drug

    Directory of Open Access Journals (Sweden)

    Maria P. Crespo-Ortiz

    2012-01-01

    Full Text Available Improvement of quality of life and survival of cancer patients will be greatly enhanced by the development of highly effective drugs to selectively kill malignant cells. Artemisinin and its analogs are naturally occurring antimalarials which have shown potent anticancer activity. In primary cancer cultures and cell lines, their antitumor actions were by inhibiting cancer proliferation, metastasis, and angiogenesis. In xenograft models, exposure to artemisinins substantially reduces tumor volume and progression. However, the rationale for the use of artemisinins in anticancer therapy must be addressed by a greater understanding of the underlying mechanisms involved in their cytotoxic effects. The primary targets for artemisinin and the chemical base for its preferential effects on heterologous tumor cells need yet to be elucidated. The aim of this paper is to provide an overview of the recent advances and new development of this class of drugs as potential anticancer agents.

  4. Experimental and calculated structural parameters of 5-trihalomethyl-4,5-dihydro-1 H-pyrazole derivatives, novel analgesic agents

    Science.gov (United States)

    Machado, Pablo; Campos, Patrick T.; Lima, Glauber R.; Rosa, Fernanda A.; Flores, Alex F. C.; Bonacorso, Helio G.; Zanatta, Nilo; Martins, Marcos A. P.

    2009-01-01

    The crystal structures of four novel analgesic agents, methyl 5-hydroxy-3- or 4-methyl-5-trichloro[trifluoro]methyl-4,5-dihydro-1 H-pyrazole-1-carboxylate, have been determined by X-ray diffractometry. The data demonstrated that the molecular packing was stabilized mainly by O sbnd H⋯O hydrogen bonds of the 5-hydroxy and 1-carboxymethyl groups. The 4,5-dihydro-1 H-pyrazole rings were obtained as almost planar structures showing RMS deviation at a range of 0.0052-0.0805 Å. Additionally, computational investigation using semi-empirical AM1 and PM3 methods were performed to find a correlation between experimental and calculated geometrical parameters. The data obtained suggest that the structural data furnished by the AM1 method is in better agreement with those experimentally determined for the above compounds.

  5. Derivatives of human complement component C3 for therapeutic complement depletion: a novel class of therapeutic agents.

    Science.gov (United States)

    Fritzinger, David C; Hew, Brian E; Lee, June Q; Newhouse, James; Alam, Maqsudul; Ciallella, John R; Bowers, Mallory; Gorsuch, William B; Guikema, Benjamin J; Stahl, Gregory L; Vogel, Carl-Wilhelm

    2008-01-01

    To obtain proteins with the complement-depleting activity of Cobra Venom Factor (CVF), but with less immunogenicity, we have prepared human C3/CVF hybrid proteins, in which the C-terminus of the alpha-chain of human C3 is exchanged with homologous regions of the C-terminus of the beta-chain of CVF. We show that these hybrid proteins are able to deplete complement, both in vitro and in vivo. One hybrid protein, HC3-1496, is shown to be effective in reducing complement-mediated damage in two disease models in mice, collagen-induced arthritis and myocardial ischemia/reperfusion injury. Human C3/CVF hybrid proteins represent a novel class ofbiologicals as potential therapeutic agents in many diseases where complement is involved in the pathogenesis.

  6. Mismatch base pairing of the mutagen 8-oxoguanine and its derivatives with adenine: A theoretical search for possible antimutagenic agents

    Science.gov (United States)

    Singh, A. K.; Mishra, P. C.

    Molecular geometries of 8-oxoguanine (8OG), those of its substituted derivatives with the substitutions CH2, CF2, CO, CNH, O, and S in place of the N7H7 group, adenine (A), and the base pairs of 8OG and its substituted derivatives with adenine were optimized using the RHF/6-31+G* and B3LYP/6-31+G* methods in gas phase. All the molecules and their hydrogen-bonded complexes were solvated in aqueous media employing the polarized continuum model (PCM) of the self-consistent reaction field (SCRF) theory using the RHF/6-31+G* and B3LYP/6-31+G* methods. The optimized geometrical parameters of the 8OG-A base pair at the RHF/6-31+G* and B3LYP/6-31+G* levels of theory agree satisfactorily with those of an oligonucleotide containing the base pair found from X-ray crystallography. The pattern of hydrogen bonding in the CF2- and O-substituted 8OG-A base pair is of Watson-Crick type and that in the unsubstituted and CH2-, CNH-, and S-substituted base pairs is of Hoogsteen type. In the CO-substituted base pair, the hydrogen bonding pattern is of neither Watson-Crick nor Hoogsteen type. The CF2-substitution appears to introduce steric hindrance for stacking of DNA bases. On the basis of these results, it appears that among all the substituted 8OG molecules considered here, the O-substituted derivative may be useful as an antimutagenic drug. It is, however, subject to experimental verification. Content:text/plain; charset="UTF-8"

  7. Synthesis and evaluation of fluorine-substituted phenyl acetate derivatives as ultra-short recovery sedative/hypnotic agents.

    Directory of Open Access Journals (Sweden)

    Heng Zhang

    Full Text Available BACKGROUND: Soft drugs are molecules that are purposefully designed to be rapidly metabolized (metabolically labile. In anesthesia, the soft drug is useful because it enables precise titration to effect and rapid recovery, which might allow swift and clear-headed recovery of consciousness and early home readiness. Propofol may cause delayed awakening after prolonged infusion. Propanidid and AZD3043 have a different metabolic pathway compared to propofol, resulting in a short-acting clinical profile. Fluorine imparts a variety of properties to certain medicines, including an enhanced absorption rate and improved drug transport across the blood-brain barrier. We hypothesized that the introduction of fluorine to the frame structure of propanidid and AZD3043 would further accelerate the swift and clear-headed recovery of consciousness. To test this hypothesis, we developed a series of fluorine-containing phenyl acetate derivatives. METHODOLOGY/PRINCIPAL FINDINGS: Fluorine-containing phenyl acetate derivatives were synthesized, and their hypnotic potencies and durations of LORR following bolus or infusion administration were determined in mice, rats and rabbits. The metabolic half-lives in the blood of various species were determined chromatographically. In vitro radioligand binding and γ-aminobutyric acidA (GABAA receptor electrophysiology studies were performed. Among the 12 synthesized fluorine-containing phenyl acetate derivatives, compound 5j induced comparable duration of LORR with AZD3043, but more rapid recovery than AZD3043, propanidid and propofol. The time of compound 5j to return to walk and behavioral recovery are approximately reduced by more than 50% compared to AZD3043 in mice and rats and rabbits. The HD50 of compound 5j decreased with increasing animal size. CONCLUSIONS/SIGNIFICANCE: The rapid recovery might make compound 5j suitable for precise titration and allow swift and clear-headed recovery of consciousness and early home

  8. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

    Science.gov (United States)

    Wirth, Marius; Niro, Giuliana; Leyerer, Kristin

    2016-01-01

    Summary Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY), a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR) studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field. PMID:27340469

  9. Synthesis and Photooxygenation of Furo[3,2-c]coumarin Derivatives as Antibacterial and DNA Intercalating Agent

    Institute of Scientific and Technical Information of China (English)

    Al-Sehemi, Abdullah G.; EI-Gogary, Sameh R.

    2012-01-01

    Syntheses of 2,3-dimethyl-4H-furo[3,2-c]coumarin and 3-phenyl-4H-furo[3,2-c]coumarin as angular furocou- marins were carried out through Williamson reaction of 4-hydroxycoumarin with a-haloketones followed by cycli- zation. Photooxygenation of the synthesized furocoumarin derivatives was performed and the photoproducts were isolated and characterized. The affinity of 2,3-dimethyl-4H-furo[3,2-c]coumarin towards DNA and the antibacterial activity were evaluated and compared with 8-methoxypsoralen (8-MOP).

  10. Design, synthesis of some new (2-aminothiazol-4-yl)methylester derivatives as possible antimicrobial and antitubercular agents.

    Science.gov (United States)

    Karuvalam, Ranjith P; Haridas, Karickal R; Nayak, Susanta K; Row, Tayur N Guru; Rajeesh, P; Rishikesan, R; Kumari, N Suchetha

    2012-03-01

    A series of (2-aminothiazol-4-yl)methylester (5a-t) derivatives were synthesized in good yields and characterized by (1)H NMR, (13)C NMR, mass spectral and elemental analyses. The crystal structure of 5a was evidenced by X-ray diffraction study. The compounds were evaluated for their preliminary in vitro antibacterial, antifungal activity and were screened for antitubercular activity against Mycobacterium tuberculosis H37Rv strain. The synthesized compounds displayed interesting antimicrobial activity. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  11. Syntheses of nicotinamide riboside and derivatives: effective agents for increasing nicotinamide adenine dinucleotide concentrations in mammalian cells.

    Science.gov (United States)

    Yang, Tianle; Chan, Noel Yan-Ki; Sauve, Anthony A

    2007-12-27

    A new two-step methodology achieves stereoselective synthesis of beta-nicotinamide riboside and a series of related amide, ester, and acid nucleosides. Compounds were prepared through a triacetylated-nicotinate ester nucleoside, via coupling of either ethylnicotinate or phenylnicotinate with 1,2,3,5-tetra-O-acetyl-beta-D-ribofuranose. Nicotinamide riboside, nicotinic acid riboside, O-ethylnicotinate riboside, O-methylnicotinate riboside, and several N-alkyl derivatives increased NAD+ concentrations from 1.2-2.7-fold in several mammalian cell lines. These findings establish bioavailability and potent effects of these nucleosides in stimulating the increase of NAD+ concentrations in mammalian cells.

  12. Synthesis, characterization and pharmacological studies of copper complexes of flavone derivatives as potential anti-tuberculosis agents.

    Science.gov (United States)

    Joseph, J; Nagashri, K; Suman, A

    2016-09-01

    Novel series of different hydroxyflavone derivatives and their copper complexes were synthesized. They were characterized using analytical and spectral techniques. The superoxide dismutase (SOD) mimetic activity of the synthesized complexes demonstrated that copper complex of L(10) has promising SOD-mimetic activity than other ligands & complexes. The in vitro antimicrobial activities of the synthesized compounds were tested against the bacterial species and fungal species. The DNA binding properties of copper complexes were studied using cyclic voltametry and electronic absorption techniques. Anti-tuberculosis activity was also performed. The effective complexes was subjected to antimycobacterial activity using MABA method and summarized. The antimycobacterial activity of copper complexes have been evaluated and discussed.

  13. Synthesis and evaluation of 1-alkyl-4-phenyl-[1,2,3]-triazole derivatives as antimycobacterial agent

    Energy Technology Data Exchange (ETDEWEB)

    Gallardo, Hugo; Conte, Gilmar; Bryk, Fernando [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Quimica]. E-mail: hugo@qmc.ufsc.br; Lourenco, Maria Cristina S. [Fundacao Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Instituto de Pesquisa Evandro Chagas; Costa, Marilia S.; Ferreira, Vitor F. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Quimica]. E-mail: cegvito@vm.uff.br

    2007-07-01

    Fourteen small molar mass 1-alkyl-4-phenyl-[1,2,3]-triazole derivatives were prepared using a straightforward and efficient method for the regioselective synthesis of [1,2,3]-triazoles and the compounds were screened for antimycobacterial activity against multiple-drug-resistant strains of Mycobacterium tuberculosis H37Rv. The synthetic methodology consisted of a Cu(I)-catalyzed 1,3-dipolar cycloaddition of aryl azides to terminal arylacetylenes (click-reaction). Six [1,2,3]-triazoles were found to be more active against M. tuberculosis than the positive control ethambutol. (author)

  14. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

    Directory of Open Access Journals (Sweden)

    Daniel Wiegmann

    2016-04-01

    Full Text Available Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY, a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field.

  15. Anti-allergic agents from natural sources (4): anti-allergic activity of new phloroglucinol derivatives from Mallotus philippensis (Euphorbiaceae).

    Science.gov (United States)

    Daikonya, Akihiro; Katsuki, Shigeki; Wu, Jin-Bin; Kitanaka, Susumu

    2002-12-01

    Two new phloroglucinol derivatives, mallotophilippen A (1). and B (2). were isolated from the fruits of Mallotus philippensis. These compounds were identified, using chemical and spectral data, as 1-[5,7-dihydroxy-2,2-dimethyl-6-(2,4,6-trihydroxy-3-isobutyryl-5-methyl-benzyl)-2H-chromen-8-yl]-2-methyl-butan-1-one and 1-[6-(3-Acetyl-2,4,6-trihydroxy-5-methyl-benzyl)-5,7-dihydroxy-2,2-dimethyl-2H-chromen-8-yl]-2-methyl-butan-1-one, respectively. They inhibited nitric oxide (NO) production and inducible NO synthase (iNOS) gene expression by a murine macrophage-like cell line (RAW 264.7), which was activated by lipopolysaccharide (LPS) and recombinant mouse interferon-gamma (IFN-gamma). Furthermore, they inhibited histamine release from rat peritoneal mast cells induced by Compound 48/80. These results suggest that the novel phloroglucinol derivatives have anti-inflammatory effects.

  16. Rebamipide, a novel antiulcer agent, attenuates Helicobacter pylori induced gastric mucosal cell injury associated with neutrophil derived oxidants.

    Science.gov (United States)

    Suzuki, M; Miura, S; Mori, M; Kai, A; Suzuki, H; Fukumura, D; Suematsu, M; Tsuchiya, M

    1994-01-01

    The effect of rebamipide, a novel antiulcer compound, on Helicobacter pylori activated neutrophil dependent in vitro gastric epithelial cell injury was investigated. Luminol dependent chemiluminescence (ChL), which detects toxic oxidants from neutrophils exhibited a 12-fold increase when the bacterial suspension of H pylori was added to the isolated human neutrophils. This change was significantly attenuated by rebamipide at a concentration less than 1 mM, showing that rebamipide may inhibit oxidant production from H pylori elicited neutrophils. To assess whether rebamipide attenuates gastric mucosal injury, we tested its inhibitory action on H pylori induced gastric mucosal damage associated with neutrophils in vitro. Rabbit gastric mucosal cells were monolayered in culture wells and coincubated with human neutrophils and H pylori, and the cytotoxicity index was then calculated. Cultured gastric cells were significantly damaged when they were incubated with human neutrophils activated by H pylori. This cellular damage was attenuated by rebamipide in a dose-dependent manner. Furthermore, spectrophotometrical measurement showed that rebamipide (1 mM) inhibits urease activity by 21.7%. As monochloramine (an oxidant yielded by reaction of neutrophil derived chlorinated oxidant and ammonia) is proposed as an important toxic molecule in this model, the current findings suggest that the preventive effect of rebamipide on H pylori elicited neutrophil induced gastric mucosal injury may result from its inhibitory actions on the neutrophilic oxidative burst as well as H pylori derived urease activity. PMID:7959190

  17. Biological evaluation of octahydropyrazin[2,1-a:5,4-a']diisoquinoline derivatives as potent anticancer agents.

    Science.gov (United States)

    Gornowicz, Agnieszka; Pawłowska, Natalia; Czajkowska, Anna; Czarnomysy, Robert; Bielawska, Anna; Bielawski, Krzysztof; Michalak, Olga; Staszewska-Krajewska, Olga; Kałuża, Zbigniew

    2017-06-01

    In this study, we evaluated the cytotoxic activity and antiproliferative potency of novel octahydropyrazin[2,1-a:5,4-a']diisoquinoline derivatives (1-7) in MCF-7 and MDA-MB-231 breast cancer cell lines. Annexin V binding assay and disruption of the mitochondrial potential were performed to determine apoptosis. The activity of caspases 3, 8, 9, and 10 was measured after 24 h of incubation with tested compounds to explain detailed molecular mechanism of induction of apoptosis. The results from experiments were compared with effects obtained after incubation in the presence of camptothecin and etoposide. Our study demonstrated that the most active compounds in both analyzed breast cancer cell lines were compounds 3 and 4. We also observed that all compounds induced apoptosis. We demonstrated the higher activity of caspases 3, 8, 9, and 10, which confirmed that induction of apoptosis is associated with external and internal cell death pathway. Our study revealed that the novel compounds in group of diisoquinoline derivatives are promising candidates in anticancer treatment by activation of both extrinsic and intrinsic apoptotic pathways.

  18. Salvianolic acid A, a polyphenolic derivative from Salvia miltiorrhiza bunge, as a multifunctional agent for the treatment of Alzheimer's disease.

    Science.gov (United States)

    Cao, Ying Ying; Wang, Ling; Ge, Hu; Lu, Xi Lin; Pei, Zhong; Gu, Qiong; Xu, Jun

    2013-08-01

    The effects of Salvianolic acid A (Sal A) on the treatment of Alzheimer's disease (AD) were investigated. Sal A significantly inhibits amyloid beta [Formula: see text] self-aggregation and disaggregates pre-formed [Formula: see text] fibrils, reduces metal-induced [Formula: see text] aggregation through chelating metal ions, and blocks the formation of reactive oxygen species (ROS) in SH-SY5Y cells. Sal A protects cells against [Formula: see text]-induced toxicity. Furthermore, Sal A, possibly because of the effects of decreasing toxicity effects of [Formula: see text] species, alleviates [Formula: see text]-induced paralysis in transgenic Caenorhabditis elegans. Circular dichroism (CD) experiments and Molecular dynamic (MD) simulations demonstrate that Sal A inhibits [Formula: see text] self-aggregation through binding to the C-terminus of [Formula: see text], and therefore stabilizing the [Formula: see text]-helical conformations. Altogether, our data show that Sal A, as the multifunctional agent, is likely to be promising therapeutics for AD.

  19. Design, synthesis, and evaluation of hydroxamic acid derivatives as promising agents for the management of Chagas disease.

    Science.gov (United States)

    Rodrigues, Giseli Capaci; Feijó, Daniel Ferreira; Bozza, Marcelo Torres; Pan, Peiwen; Vullo, Daniela; Parkkila, Seppo; Supuran, Claudiu T; Capasso, Clemente; Aguiar, Alcino Palermo; Vermelho, Alane Beatriz

    2014-01-23

    Today, there are approximately 8 million cases of Chagas disease in the southern cone of South America alone, and about 100 million people are living with the risk of becoming infected. The present pharmacotherapy is sometimes ineffective and has serious side effects. Here, we report a series of 4,5-dihydroisoxazoles incorporating hydroxamate moieties, which act as effective inhibitors of the carbonic anhydrase (CA) from Trypanosoma cruzi (TcCA). One compound (5g) was evaluated in detail and shows promising features as an antitrypanosomal agent. Excellent values for the inhibition of growth for all three developmental forms of the parasite were observed at low concentrations of 5g (IC50 values from 7.0 to <1 μM). The compound has a selectivity index (SI) of 6.7 and no cytotoxicity to macrophage cells. Preliminary in vivo data showed that 5g reduces bloodstream parasites and that all treated mice survived; it was also more effective than the standard drug benznidazole.

  20. Design, Synthesis and Biological Evaluation of Novel Phosphorylated Abacavir Derivatives as Antiviral Agents Against Newcastle Disease Virus Infection in Chicken.

    Science.gov (United States)

    K A, Suresh; Venkata Subbaiah, Kadiam C; Lavanya, Rayapu; Chandrasekhar, Kuruva; Chamarti, Naga Raju; Kumar, M Suresh; Wudayagiri, Rajendra; Valluru, Lokanatha

    2016-09-01

    Newcastle disease virus is the most devastating virus in poultry industry. It can eradicate the entire poultry flocks once infected. This study is aimed to investigate the antiviral efficacy of novel phosphorylated analogues of the drug abacavir (ABC) against Newcastle disease virus (NDV). About 16 analogues of ABC were designed and docking was performed against fusion protein of NDV. Three compounds were identified and selected for synthesis and biological evaluation based on binding affinity and docking scores. The compounds were synthesized and characterized by IR, (1)H, (13)C, (31)P and CHN analysis and mass spectra. These compounds were tested for antiviral efficacy against NDV-infected DF-1 cells. Compound ABC-1 had shown potent antiviral activity as evidenced by significant reduction in plaque units and cytopathic effect. Therefore, ABC-1 was selected to test for NDV-infected chicken survival rate. Effective dose50 concentrations were determined for ABC-1. Antioxidant enzyme levels in brain, liver and lung tissues were estimated. Superoxide dismutase and catalase were significantly raised and lipid peroxidation and HA titer levels were decreased upon treatment with 2 mg/kg body weight ABC-1. Histopathological modifications were also restored in the ABC-1-treated group. These findings demonstrated ABC-1 as a potential antiviral agent against NDV in chicken.

  1. Design, synthesis, biological evaluation and molecular docking studies of novel benzofuran-pyrazole derivatives as anticancer agents.

    Science.gov (United States)

    Abd El-Karim, Somaia S; Anwar, Manal M; Mohamed, Neama A; Nasr, Tamer; Elseginy, Samia A

    2015-12-01

    This study deals with design and synthesis of novel benzofuran-pyrazole hybrids as anticancer agents. Eight compounds were chosen by National Cancer Institute (NCI), USA to evaluate their in vitro antiproliferative activity at 10(-5)M in full NCI 60 cell panel. The preliminary screening of the tested compounds showed promising broad-spectrum anticancer activity. Compound 4c was further assayed for five dose molar ranges in full NCI 60 cell panel and exhibited remarkable growth inhibitory activity pattern against Leukemia CCRF-CEM, MOLT-4, Lung Cancer HOP-92, Colon Cancer HCC-2998, CNS Cancer SNB-75, Melanoma SK-MEL-2, Ovarian Cancer IGROV1, Renal Cancer 786-0, RXF 393, Breast Cancer HS 578T and T-47D (GI50: 1.00-2.71μM). Moreover, enzyme assays were carried out to investigate the possible antiproliferative mechanism of action of compound 4c. The results revealed that compound 4c has good c-Src inhibitory activity at 10μM. In addition, molecular docking studies showed that 4c could bind to the ATP Src pocket sites. Fulfilling the Lipinskiís rule of five in addition to its ADME profile and the biological results, all strongly suggest that 4c is a promising Src kinase inhibitor.

  2. Plant-Derived Antimalarial Agents: New Leads and Efficient Phytomedicines. Part II. Non-Alkaloidal Natural Products

    Directory of Open Access Journals (Sweden)

    Alaíde Braga de Oliveira

    2009-08-01

    Full Text Available Malaria is still the most destructive and dangerous parasitic infection in many tropical and subtropical countries. The burden of this disease is getting worse, mainly due to the increasing resistance of Plasmodium falciparum against the widely available antimalarial drugs. There is an urgent need for new, more affordable and accessible antimalarial agents possessing original modes of action. Natural products have played a dominant role in the discovery of leads for the development of drugs to treat human diseases, and this fact anticipates that new antimalarial leads may certainly emerge from tropical plant sources. This present review covers most of the recently-published non-alkaloidal natural compounds from plants with antiplasmodial and antimalarial properties, belonging to the classes of terpenes, limonoids, flavonoids, chromones, xanthones, anthraquinones, miscellaneous and related compounds, besides the majority of papers describing antiplasmodial crude extracts published in the last five years not reviewed before. In addition, some perspectives and remarks on the development of new drugs and phytomedicines for malaria are succinctly discussed.

  3. Causatives as complex predicates without the restriction operator

    NARCIS (Netherlands)

    Homola, Petr; Coler, Matthew

    2013-01-01

    lsina’s (1996) concept of complex predicates has been, within LFG, applied to a number of phenomena and languages including, for example, Turkish causatives (Çetinoglu et al., 2008). These approaches are comparable insofar as they use the so-called restriction operator introduced by Kaplan and

  4. The Nature of the Entrepreneurial Process: Causation, Effectuation, and Pragmatism

    NARCIS (Netherlands)

    Kraaijenbrink, Jeroen

    2008-01-01

    This paper forms an appreciation of and a critical reflection on Sarasvathy’s work on causation and effectuation models of entrepreneurship. While Sarasvathy has made significant contributions to the field, it is suggested that a more fruitful approach can follow if two modifications are made.

  5. Standard Javanese Causatives in online editorials and short stories

    Directory of Open Access Journals (Sweden)

    Noor Malihah

    2014-06-01

    Full Text Available This paper explores the distinctive features of the standard Javanese causatives in on-line editorials and short stories. This research is based on written corpus. This written corpus was compiled from articles published in an online newspaper Solo Pos. To analyze the corpus, I have developed a system of manual annotation to identify the features of verb transitivity, the animacy and humanness of the verb, the presence of active, passive and ergative-like clauses and the number of other grammatical and semantic features using a system of tags. Using this annotation, I analyze the data based on dua anlaysis: genre analysis, functional analysis using a quantitative method. The findings show that genre influences the selection of causative types (markers. Also, there exists gawe used as a verb of causation in both editorials and short stories which contradicts to the canonical rule of the Javanese active verb and Malihah’s (2014 findings. The finding also shows that the standard Javanese causative in online editorials and short stories occurs with intransitive verbs. The last finding is that active clause is the relative prominent type of clause which occurs in all marker. In conclusion, the above findings have made contributions to knowledge to Javanese grammar.

  6. Cyclopentadienyl-ruthenium(II) and iron(II) organometallic compounds with carbohydrate derivative ligands as good colorectal anticancer agents.

    Science.gov (United States)

    Florindo, Pedro R; Pereira, Diane M; Borralho, Pedro M; Rodrigues, Cecília M P; Piedade, M F M; Fernandes, Ana C

    2015-05-28

    New ruthenium(II) and iron(II) organometallic compounds of general formula [(η(5)-C5H5)M(PP)Lc][PF6], bearing carbohydrate derivative ligands (Lc), were prepared and fully characterized and the crystal structures of five of those compounds were determined by X-ray diffraction studies. Cell viability of colon cancer HCT116 cell line was determined for a total of 23 organometallic compounds and SAR's data analysis within this library showed an interesting dependency of the cytotoxic activity on the carbohydrate moiety, linker, phosphane coligands, and metal center. More importantly, two compounds, 14Ru and 18Ru, matched oxaliplatin IC50 (0.45 μM), the standard metallodrug used in CC chemotherapeutics, and our leading compound 14Ru was shown to be significantly more cytotoxic than oxaliplatin to HCT116 cells, triggering higher levels of caspase-3 and -7 activity and apoptosis in a dose-dependent manner.

  7. A facile microwave assisted one pot synthesis of novel xanthene derivatives as potential anti-inflammatory and analgesic agents

    Directory of Open Access Journals (Sweden)

    Anupam G. Banerjee

    2016-09-01

    Full Text Available Microwave assisted irradiation of resorcinol and substituted aryl aldehydes using sulfamic acid as catalyst afforded novel 9-aryl-9H-xanthene-3,6-diol derivatives (1a–f in good yields. The newly synthesized compounds which were previously selected on the basis of PASS prediction were tested for anti-inflammatory activity using carrageenan-induced rat paw edema and analgesic activity using acetic acid induced writhing and formalin-induced paw edema in mice along with the estimation of gastric ulcerogenicity index. Compounds 1e and 1f exhibited significant anti-inflammatory and analgesic activities as compared to standard drug. The study also revealed that compounds (1a–f showed minimum or no ulcerogenicity in mice as that of the standard drug.

  8. Synthesis and pharmacological evaluation of 1-isopropyl-1,2,3,4-tetrahydroisoquinoline derivatives as novel antihypertensive agents.

    Science.gov (United States)

    Watanuki, Susumu; Matsuura, Keisuke; Tomura, Yuichi; Okada, Minoru; Okazaki, Toshio; Ohta, Mitsuaki; Tsukamoto, Shin-Ichi

    2011-01-01

    A series of 1-isopropyl-1,2,3,4-tetrahydroisoquinoline derivatives were synthesized and their bradycardic activities were evaluated in isolated guinea pig right atria. Structure-activity relationship studies revealed that the introduction of an appropriate substituent and its position on the 1,2,3,4-tetrahydroisoquinoline ring are essential for potent in vitro activity. Furthermore, the tether between the piperidyl moiety and the terminal aromatic ring is important for potent antihypertensive activity. Oral administration of 6-fluoro-1-isopropyl-2-{[1-(2-phenylethyl)piperidin-4-yl]carbonyl}-1,2,3,4-tetrahydroisoquinoline (3b) to spontaneously hypertensive rats (SHR) elicited antihypertensive effects without inducing reflex tachycardia, which is often caused by traditional L-type Ca²⁺ channel blockers.

  9. A geo-information system approach for forest fire likelihood based on causative and anti - causative factors

    NARCIS (Netherlands)

    Srivastava, Sanjay K.; Saran, Sameer; de By, R.A.; Dadhwal, V.K.

    2014-01-01

    Innumerable forest fire spread models exist for taking a decision, but far less focus is on the real causative factors which initiate/ignite fire in an area. It has been observed that the majority of the forest fires in India are initiated due to anthropogenic factors. In this study, we develop a

  10. Synthesis and Biological Activity Evaluation of Novel α-Amino Phosphonate Derivatives Containing a Pyrimidinyl Moiety as Potential Herbicidal Agents.

    Science.gov (United States)

    Chen, Jin-Long; Tang, Wu; Che, Jian-Yi; Chen, Kai; Yan, Gang; Gu, Yu-Cheng; Shi, De-Qing

    2015-08-19

    To find novel high-activity and low-toxicity herbicide lead compounds with novel herbicidal mode of action, series of novel α-amino phosphonate derivatives containing a pyrimidinyl moiety, I, II, III, and IV, were designed and synthesized by Lewis acid (magnesium perchlorate) catalyzed Mannich-type reaction of aldehydes, amines, and phosphites. Their structures were clearly identified by spectroscopy data (IR, (1)H NMR, (31)P NMR, EI-MS) and elemental analyses. The bioassay [in vitro, in vivo (GH1 and GH2)] showed that most compounds I exhibited good herbicidal activities; for example, the activities of compounds Ib, Ic, Ig, Ii, Ik, and Im were as good as the positive control herbicides (acetochlor, atrazine, mesotrione, and glyphosate). However, their structural isomers II and III and analogues IV did not display any herbicidal activities in vivo, although some of them possessed selective inhibitory activity against Arabidopsis thaliana in vitro. Interestingly, it was found that compounds IVs, IVt, and IVl showed selective insecticidal activities against Aphis species or Plutella xylostella, respectively. Their preliminary herbicidal mode of action and structure-activity relationships were also studied.

  11. A novel bioactive tyramine derived Schiff base and its transition metal complexes as selective DNA binding agents

    Science.gov (United States)

    Raman, N.; Sobha, S.; Thamaraichelvan, A.

    2011-02-01

    A novel tyramine derived Schiff base, 3-4-dimethoxybenzylidene-4-aminoantipyrinyl-4-aminoethylphenol(L) and a series of its transition metal complexes of the type, ML 2Cl 2 where, M = Cu(II), Ni(II), Co(II) and Zn(II) have been designed and synthesized. Their structural features and other properties were deduced from the elemental analysis, magnetic susceptibility and molar conductivity as well as from mass, IR, UV-vis, 1H NMR and EPR spectral studies. The binding properties of these complexes with calf thymus DNA (CT-DNA) were investigated using electronic absorption spectroscopy, viscosity measurement, cyclic voltammetry and molecular docking analysis. The results reveal that the metal(II) complexes interact with DNA through minor groove binding. The interaction has also been investigated by gel electrophoresis. Interestingly, it was found that all the complexes could cleave the circular plasmid pUC19 super coiled (SC) DNA efficiently in the presence of AH 2 (ascorbic acid). The complexes showed enhanced antifungal and antibacterial activities compared to the free ligand.

  12. Design and Synthesis of 5-Substituted Benzo[d][1,3]dioxole Derivatives as Potent Anticonvulsant Agents.

    Science.gov (United States)

    Dong, Shiyang; Wang, Tiantian; Hu, Chundi; Chen, Xiaodong; Jin, Yi; Wang, Zengtao

    2017-02-01

    A series of 5-substituted benzo[d][1,3]dioxole derivatives was designed, synthesized, and tested for anticonvulsant activity using the maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) screens. Neurotoxicity was determined by rotarod test. In the preliminary screening, six compounds, 3a, 3c, 3d, and 4d-f, showed promising anticonvulsant activities in the MES model, and compounds 4c and 4d exhibited full protection against seizures at doses of 300 mg/kg in the scPTZ model. Among the synthesized compounds, 3c as the most active compound showed high protection against the MES-induced seizures with an ED50 value of 9.8 mg/kg and a TD50 value of 229.4 mg/kg after intraperitoneal injection into mice, thus providing compound 3c with a high protective index (TD50 /ED50 ) of 23.4 comparable to those of reference antiepileptic drugs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Synthesis and Pharmacological Evaluation of New 3,4-Dihydroisoquinolin Derivatives Containing Heterocycle as Potential Anticonvulsant Agents

    Directory of Open Access Journals (Sweden)

    Hong-Jian Zhang

    2016-11-01

    Full Text Available Two novel series of 3,4-dihydroisoquinolin with heterocycle derivatives (4a–t and 9a–e were synthesized and evaluated for their anticonvulsant activity using maximal electroshock (MES test and pentylenetetrazole (PTZ-induced seizure test. All compounds were characterized by IR, 1H-NMR, 13C-NMR, and mass spectral data. Among them, 9-(exyloxy-5,6-dihydro-[1,2,4]triazolo[3,4-a]isoquinolin-3(2H-one (9a showed significant anticonvulsant activity in MES tests with an ED50 value of 63.31 mg/kg and it showed wide margins of safety with protective index (PI > 7.9. It showed much higher anticonvulsant activity than that of valproate. It also demonstrated potent activity against PTZ-induced seizures. A docking study of compound 9a in the benzodiazepine (BZD-binding site of γ-aminobutyric acidA (GABAA receptor confirmed possible binding of compound 9a with the BZD receptors.

  14. Study of the structural and electronic properties of valproic acid and new derivatives used as anticonvulsant agents.

    Science.gov (United States)

    Comelli, Nieves C; Lobayan, Rosana M; Castro, Eduardo A; Jubert, Alicia H

    2011-03-10

    The conformational and electronic characteristics of the polar O(9)═C(8)-X(10) moiety in the anticonvulsant valproic acid (Vpa) drug and some of their amides and ester derivatives are analyzed at the B3LYP level using the 6-31+G(d,p) and 6-311++G(d,p) 6d,10f basis sets. Exploring the delocalization of the electron density of the O(9)═C(8)-X(10) moiety by means of ELF, NBO, and AIM calculations, we found that the bending away from coplanarity of the atoms in O(9)═C(8)-X(10) is accompanied by a three-dimensional arrangement of donor and acceptor proton units closing nearly planar pseudorings of four, five, and six members arising from stabilizing interactions around the O(9)═C(8)-X(10) backbone. From the structure-property relationship analysis, we explain the origin of the change in the structural parameters and atomic charges in the polar moiety.

  15. Synthesis, biological evaluation and molecular modeling of novel series of pyridine derivatives as anticancer, anti-inflammatory and analgesic agents

    Science.gov (United States)

    Helal, M. H.; El-Awdan, S. A.; Salem, M. A.; Abd-elaziz, T. A.; Moahamed, Y. A.; El-Sherif, A. A.; Mohamed, G. A. M.

    2015-01-01

    This paper presents a combined synthesis; characterization, computational and biological activity studies of novel series of pyridines heterocyclic compounds. The compounds have been characterized by elemental analyses and spectral like IR, 1H NMR, 13C NMR and MS studies. Michael addition of substituted-2-methoxycarbonylacetanilide 2a,b on the α-substituted cinnamonitriles 3a-d gave the corresponding 2-pyridone derivatives 5-10. Structures of the titled compounds cited in this article were elucidated by spectrometric data (IR, 1H NMR, 13C NMR and MS). The molecular modeling of the synthesized compounds has been drawn and their molecular parameters were calculated. Also, valuable information is obtained from the calculation of molecular parameters including electronegativity, net dipole moment of the compounds, total energy, electronic energy, binding energy, HOMO and LUMO energy. Various in vitro antitumor as well as in vivo anti-inflammatory and analgesic activities of the synthesized compounds were investigated. Evaluation of anti-inflammatory activity of test compounds was performed using carrageenan induced paw edema in rats. All the tested compounds showed moderate to good activity. The SAR results indicate that all compounds showed moderate to good activity, among these 7 and 10 compounds having -N(CH3)2 group are most effective.

  16. Regioselective synthesis and biological studies of novel 1-aryl-3, 5-bis (het) aryl pyrazole derivatives as potential antiproliferative agents.

    Science.gov (United States)

    Ananda, Hanumappa; Sharath Kumar, Kothanahally S; Nishana, Mayilaadumveettil; Hegde, Mahesh; Srivastava, Mrinal; Byregowda, Raghava; Choudhary, Bibha; Raghavan, Sathees C; Rangappa, Kanchugarakoppal S

    2017-02-01

    Pyrazole moiety represents an important category of heterocyclic compound in pharmaceutical and medicinal chemistry. The novel 1-aryl-3, 5-bis (het) aryl pyrazole derivatives were synthesized with complementary regioselectivity. The chemical structures were confirmed by IR, (1)H NMR, (13)C NMR, and mass spectral analysis. The chemical entities were screened in various cancer cell lines to assess their cell viability activity. Results showed that the compound 3-(1-(4-bromophenyl)-5-phenyl-1H-pyrazol-3-yl) pyridine (5d) possessed maximum cytotoxic effect against breast cancer and leukemic cells. The cytotoxicity was confirmed by live-dead cell assay and cell cycle analysis. Mitochondrial membrane potential, Annexin V-FITC staining, DNA fragmentation, Hoechst staining, and western blot assays revealed the ability of compound 5d to induce cell death by activating apoptosis in cancer cells. Thus, the present study demonstrates that compound 5d could be an attractive chemical entity for the development of small molecule inhibitors for treatment of leukemia and breast cancer.

  17. Synthesis, molecular docking, and biological evaluation of some novel hydrazones and pyrazole derivatives as anti-inflammatory agents.

    Science.gov (United States)

    Mohammed, Khaled O; Nissan, Yassin M

    2014-10-01

    2-Hydrazinyl-N-(4-sulfamoylphenyl)acetamide 3 was the key intermediate for the synthesis of novel hydrazones 4-10 and pyrazole derivatives 11-17. All compounds were tested for their in vivo anti-inflammatory activity and their ability to inhibit the production of PGE(2) in serum samples of rats. IC(50) values for the most active compounds for inhibition of COX-1 and COX-2 enzymes were determined in vitro, and they were also tested for their ulcerogenic effect. Molecular docking was performed on the active site of COX-2 to predict their mode of binding to the amino acids. Most of the synthesized compounds showed good anti-inflammatory activity especially compounds 3, 4, 8, 9, 15, and 17 which showed better activity than diclofenac as the reference drug. Compounds 3, 8, 9, 13, and 15-17 were less ulcerogenic than indomethacine as the reference drug. Most of the synthesized compounds interacted with Tyr 385 and Ser 530 in molecular docking study with additional hydrogen bond for compound 17. Compound 17 showed good selectivity index value of 11.1 for COX-1/COX-2 inhibition in vitro.

  18. Synthesis and biological evaluation of new boron-containing chlorin derivatives as agents for both photodynamic therapy and boron neutron capture therapy of cancer.

    Science.gov (United States)

    Asano, Ryuji; Nagami, Amon; Fukumoto, Yuki; Miura, Kaori; Yazama, Futoshi; Ito, Hideyuki; Sakata, Isao; Tai, Akihiro

    2014-03-01

    New boron-containing chlorin derivatives 9 and 13 as agents for both photodynamic therapy (PDT) and boron neutron capture therapy (BNCT) of cancer were synthesized from photoprotoporphyrin IX dimethyl ester (2) and L-4-boronophenylalanine-related compounds. The in vivo biodistribution and clearance of 9 and 13 were investigated in tumor-bearing mice. The time to maximum accumulation of compound 13 in tumor tissue was one-fourth of that of compound 9, and compound 13 showed rapid clearance from normal tissues within 24h after injection. The in vivo therapeutic efficacy of PDT using 13 was evaluated by measuring tumor growth rates in tumor-bearing mice with 660 nm light-emitting diode irradiation at 3h after injection of 13. Tumor growth was significantly inhibited by PDT using 13. These results suggested that 13 might be a good candidate for both PDT and BNCT of cancer.

  19. Design, Synthesis and Structure-Activity Relationships of Novel Chalcone-1,2,3-triazole-azole Derivates as Antiproliferative Agents.

    Science.gov (United States)

    Zhang, Sai-Yang; Fu, Dong-Jun; Yue, Xiao-Xin; Liu, Ying-Chao; Song, Jian; Sun, Hui-Hui; Liu, Hong-Min; Zhang, Yan-Bing

    2016-05-19

    A series of novel chalcone-1,2,3-triazole-azole hybrids were designed, synthesized and evaluated for their antiproliferative activity against three selected cancer cell lines (SK-N-SH, EC-109 and MGC-803). Most of the synthesized compounds exhibited moderate to good activity against all the cancer cell lines selected. Particularly, compound I-21 showed the most excellent antiproliferative activity with an IC50 value of 1.52 μM against SK-N-SH cancer cells. Further mechanism studies revealed that compound I-21 induced morphological changes of SK-N-SH cancer cells possibly by inducing apoptosis. Novel chalcone-1,2,3-triazole-azole derivatives in this work might be a series of promising lead compounds to develop anticancer agents for treating neuroblastoma.

  20. Design and Synthesis of Chalcone Derivatives as Inhibitors of the Ferredoxin — Ferredoxin-NADP+ Reductase Interaction of Plasmodium falciparum: Pursuing New Antimalarial Agents

    Directory of Open Access Journals (Sweden)

    Hery Suwito

    2014-12-01

    Full Text Available Some chalcones have been designed and synthesized using Claisen-Schmidt reactions as inhibitors of the ferredoxin and ferredoxin-NADP+ reductase interaction to pursue a new selective antimalaria agent. The synthesized compounds exhibited inhibition interactions between PfFd-PfFNR in the range of 10.94%–50%. The three strongest inhibition activities were shown by (E-1-(4-aminophenyl-3-(4-methoxyphenylprop-2-en-1-one (50%, (E-1-(4-aminophenyl-3-(2,4-dimethoxyphenylprop-2-en-1-one (38.16%, and (E-1-(4-aminophenyl-3-(2,3-dimethoxyphenylprop-2-en-1-one (31.58%. From the docking experiments we established that the amino group of the methoxyamino chlacone derivatives plays an important role in the inhibition activity by electrostatic interaction through salt bridges and that it forms more stable and better affinity complexes with FNR than with Fd.

  1. Studies on chemical modification and biology of a natural product, gambogic acid (II): Synthesis and bioevaluation of gambogellic acid and its derivatives from gambogic acid as antitumor agents.

    Science.gov (United States)

    Wang, Jinxin; Ma, Junhai; You, Qidong; Zhao, Li; Wang, Fan; Li, Chong; Guo, Qinglong

    2010-09-01

    Gambogic acid (GA) has been reported to be a potent apoptosis inducer. The fact that it is amenable to chemical modification makes GA an attractive molecule for the development of anticancer agents. We firstly reported the synthesis of gambogellic acid, which was generated under acid catalysis from readily available GA by a base-catalyzed diene intramolecular annelation. Sequentially, thirteen new compounds were synthesized and their inhibitory activity on HT-29, Bel-7402, BGC-823, and A549 cell lines were evaluated in vitro by MTT assay, and (38, 40)-epoxy-33-chlorogambogellic acid (4) was identified as a BGC-823 cell apoptosis inducer through MTT cell assay, observations of morphological changes, and Annexin-V/PI double-staining assay. Compound 4 showed significant effects in inducing apoptosis and might serve as a potential lead compound for discovery of new anticancer drugs. Further structure-activity relationships (SARs) of gambogic acid derivatives were discussed.

  2. Design, Synthesis and Structure-Activity Relationships of Novel Chalcone-1,2,3-triazole-azole Derivates as Antiproliferative Agents

    Directory of Open Access Journals (Sweden)

    Sai-Yang Zhang

    2016-05-01

    Full Text Available A series of novel chalcone-1,2,3-triazole-azole hybrids were designed, synthesized and evaluated for their antiproliferative activity against three selected cancer cell lines (SK-N-SH, EC-109 and MGC-803. Most of the synthesized compounds exhibited moderate to good activity against all the cancer cell lines selected. Particularly, compound I-21 showed the most excellent antiproliferative activity with an IC50 value of 1.52 μM against SK-N-SH cancer cells. Further mechanism studies revealed that compound I-21 induced morphological changes of SK-N-SH cancer cells possibly by inducing apoptosis. Novel chalcone-1,2,3-triazole-azole derivatives in this work might be a series of promising lead compounds to develop anticancer agents for treating neuroblastoma.

  3. In vitro antibacterial activity of sphaeropsidins and chemical derivatives toward Xanthomonas oryzae pv. oryzae, the causal agent of rice bacterial blight.

    Science.gov (United States)

    Evidente, Antonio; Venturi, Vittorio; Masi, Marco; Degrassi, Giuliano; Cimmino, Alessio; Maddau, Lucia; Andolfi, Anna

    2011-12-27

    Sphaeropsidin A, the main phytotoxin produced by Diplodia cupressi, as well as the two natural analogues sphaeropsidins B and C and 14 derivatives obtained by chemical modifications were assayed for antibacterial activity against Xanthomonas oryzae pv. oryzae, Pseudomonas fuscovaginae, and Burkholderia glumae, the causal agents of severe bacterial rice diseases. The results showed a strong and specific activity of sphaeropsidin A against X. oryzae pv. oryzae, while no activity was observed against the other two pathogens. The results of structure-activity relationship studies showed that structural features important to impart this antibacterial activity are the presence of the C-7 carbonyl group and the hemiketalic lactone functionality. The C-13 vinyl group, the double bond of ring C, and/or the tertiary C-9 hydroxy group, as well as the pimarane arrangement of the tricylic carbon skeleton, were also important for the antibacterial activity. These findings may be useful in designing novel compounds for practical applications in agriculture.

  4. Anti-cancer agents based on N-acyl-2, 3-dihydro-1H-pyrrolo[2,3-b] quinoline derivatives and a method of making

    Science.gov (United States)

    Gakh, Andrei; Krasavin, Mikhail; Karapetian, Ruben; Rufanov, Konstantin A; Konstantinov, Igor; Godovykh, Elena; Soldatkina, Olga; Sosnov, Andrey V

    2013-04-16

    The present disclosure relates to novel compounds that can be used as anti-cancer agents in the prostate cancer therapy. In particular, the invention relates to N-acyl derivatives of 2,3-dihydro-1H-pyrrolo[2,3-b]quinolines having the structural Formula (I), ##STR00001## stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof. The meaning of R1 is independently selected from H; C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl substituents; R2 is selected from C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl; substituted or non-substituted, fused or non-fused to substituted or non-substituted aromatic ring, aryl or heteroaryl groups. The invention also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  5. The Chondrogenic Induction Potential for Bone Marrow-Derived Stem Cells between Autologous Platelet-Rich Plasma and Common Chondrogenic Induction Agents: A Preliminary Comparative Study

    Directory of Open Access Journals (Sweden)

    Shan-zheng Wang

    2015-01-01

    Full Text Available The interests in platelet-rich plasma (PRP and their application in stem cell therapy have contributed to a better understanding of the basic biology of the prochondrogenesis effect on bone marrow-derived stem cells (BMSCs. We aimed at comparing the effect of autologous PRP with common chondrogenic induction agents (CCIAs on the chondrogenic differentiation of BMSCs. Rabbit BMSCs were isolated and characterized by flow cytometry and differentiated towards adipocytes and osteoblasts. The chondrogenic response of BMSCs to autologous PRP and CCIAs which included transforming growth factor-β1 (TGF-β1, dexamethasone (DEX, and vitamin C (Vc was examined by cell pellet culture. The isolated BMSCs after two passages highly expressed CD29 and CD44 but minimally expressed CD45. The osteogenic and adipogenic differentiation potentials of the isolated BMSCs were also confirmed. Compared with common CCIAs, autologous PRP significantly upregulated the chondrogenic related gene expression, including Col-2, AGC, and Sox-9. Osteogenic related gene expression, including Col-1 and OCN, was not of statistical significance between these two groups. Thus, our data shows that, compared with common chondrogenic induction agents, autologous PRP can be more effective in promoting the chondrogenesis of BMSCs.

  6. Synthesis and Biological Evaluation of Novel Furozan-Based Nitric Oxide-Releasing Derivatives of Oridonin as Potential Anti-Tumor Agents

    Directory of Open Access Journals (Sweden)

    Hao Cai

    2012-06-01

    Full Text Available To search for novel nitric oxide (NO releasing anti-tumor agents, a series of novel furoxan/oridonin hybrids were designed and synthesized. Firstly, the nitrate/nitrite levels in the cell lysates were tested by a Griess assay and the results showed that these furoxan-based NO-releasing derivatives could produce high levels of NO in vitro. Then the anti-proliferative activity of these hybrids against four human cancer cell lines was also determined, among which, 9h exhibited the most potential anti-tumor activity with IC50 values of 1.82 µM against K562, 1.81 µM against MGC-803 and 0.86 µM against Bel-7402, respectively. Preliminary structure-activity relationship was concluded based on the experimental data obtained. These results suggested that NO-donor/natural product hybrids may provide a promising approach for the discovery of novel anti-tumor agents.

  7. Efficient Synthesis and Biological Evaluation of a Novel Series of 1,5-Benzodiazepine Derivatives as Potential Antimicrobial Agents.

    Science.gov (United States)

    An, Ying-Shuang; Hao, Zhen-Fang; Zhang, Xiu-Jun; Wang, Lan-Zhi

    2016-07-01

    A series of novel 1,5-benzodiazepine derivatives were rationally designed and synthesized following the principle of the superposition of bioactive substructures by the combination of 1,5-benzodiazepine, pyridine (phenyl), and an ester group. The structures of the target compounds were determined by (1) H NMR, (13) C NMR, MS, IR, and elemental analysis. All the synthesized compounds were evaluated for their antimicrobial activities in vitro against the fungi C. neoformans, C. neoformans clinical isolates (ATCC 32264), C. albicans (ATCC 10231), Gram-negative bacterium E. coli (ATCC 44752), and Gram-positive bacterium S. aureus (ATCC 25923). The results of the bioactive assay demonstrated that most of the tested compounds exhibited variable inhibitory effects on the growth of the tested microorganisms. All the active compounds showed better antifungal activity than antibacterial activity. Notably, compound 2b displayed the highest activity (MIC = 30 μg/mL) against C. neoformans and (MIC = 31 μg/mL) against C. neoformans clinical isolates. In addition, compound 2a also showed excellent activity against C. neoformans and C. neoformans clinical isolates with minimum inhibitory concentration of 35 and 36 μg/mL, respectively. Compounds 2a and 2b were further studied by evaluating their cytotoxicities, and the results showed that they have relatively low level cytotoxicity for BV2 and 293T cell. Preliminary structure-activity relationship study on three diverse sets (C-2, C-3, and C-8 positions) of 1,5-benzodiazepines was performed. The results revealed that the presence of a -CH3 group at the C-8 position had a positive effect on the inhibitory activity of these compounds. Additionally, the 2-pyridyl group at the C-2 position may be a pharmacophore and -COOC2 H5 at C-3 position is the best substituent for the maintenance of antimicrobial activities.

  8. Different sensitivities of rat skeletal muscles and brain to novel anti-cholinesterase agents, alkylammonium derivatives of 6-methyluracil (ADEMS)

    Science.gov (United States)

    Petrov, Konstantin A; Yagodina, Lilia O; Valeeva, Guzel R; Lannik, Natalya I; Nikitashina, Alexandra D; Rizvanov, Albert A; Zobov, Vladimir V; Bukharaeva, Ellya A; Reznik, Vladimir S; Nikolsky, Eugeny E; Vyskočil, František

    2011-01-01

    BACKGROUND AND PURPOSE The rat respiratory muscle diaphragm has markedly lower sensitivity than the locomotor muscle extensor digitorum longus (EDL) to the new acetylcholinesterase (AChE) inhibitors, alkylammonium derivatives of 6-methyluracil (ADEMS). This study evaluated several possible reasons for differing sensitivity between the diaphragm and limb muscles and between the muscles and the brain. EXPERIMENTAL APPROACH Increased amplitude and prolonged decay time of miniature endplate currents were used to assess anti-cholinesterase activity in muscles. In hippocampal slices, induction of synchronous network activity was used to follow cholinesterase inhibition. The inhibitor sensitivities of purified AChE from the EDL and brain were also estimated. KEY RESULTS The intermuscular difference in sensitivity to ADEMS is partly explained caused by a higher level of mRNA and activity of 1,3-bis[5(diethyl-o-nitrobenzylammonium)pentyl]-6-methyluracildibromide (C-547)-resistant BuChE in the diaphragm. Moreover, diaphragm AChE was more than 20 times less sensitive to C-547 than that from the EDL. Sensitivity of the EDL to C-547 dramatically decreased after treadmill exercises that increased the amount of PRiMA AChE(G4), but not ColQ AChE(A12) molecular forms. The A12 form present in muscles appeared more sensitive to C-547. The main form of AChE in brain, PRiMA AChE(G4), was apparently less sensitive because brain cholinesterase activity was almost three orders of magnitude more resistant to C-547 than that of the EDL. CONCLUSIONS AND IMPLICATIONS Our findings suggest that ADEMS compounds could be used for the selective inhibition of AChEs and as potential therapeutic tools. PMID:21232040

  9. Synthesis and biological evaluation of quinazolin-4(3H)-one derivatives bearing dithiocarbamate side chain at C2-position as potential antitumor agents.

    Science.gov (United States)

    Ding, Pan-Pan; Gao, Man; Mao, Bei-Bei; Cao, Sheng-Li; Liu, Cui-Huan; Yang, Chao-Rui; Li, Zhong-Feng; Liao, Ji; Zhao, Hongchang; Li, Zheng; Li, Jing; Wang, Hailong; Xu, Xingzhi

    2016-01-27

    A series of quinazolin-4(3H)-one derivatives bearing dithiocarbamate side chain at the C2-position were synthesized and evaluated for their antiproliferative activities against A549, MCF-7, HeLa, HT29 and HCT-116 cell lines. Most of the synthesized compounds exhibited broad spectrum antitproliferative activity against five cell lines, of which 5c was the most potent against HT29 cell line with an IC50 value of 5.53 μM, inducing a G2/M phase arrest in HT29 cells. Treatment of HT29 cells with 5c resulted in BubR1 phosphorylation and an increase of mitotic index in a time-dependent manner. Furthermore, 5c promoted tubulin polymerization in vitro. These results demonstrate that quinazolin-4(3H)-one derivatives bearing dithiocarbamate side chain at C2-position may be potentially novel antitumor agents targeting tubulin to activate the spindle assembly checkpoint.

  10. 3D-QSAR and Docking Studies of a Series of β-Carboline Derivatives as Antitumor Agents of PLK1

    Directory of Open Access Journals (Sweden)

    Jahan B. Ghasemi

    2014-01-01

    Full Text Available An alignment-free, three dimensional quantitative structure-activity relationship (3D-QSAR analysis has been performed on a series of β-carboline derivatives as potent antitumor agents toward HepG2 human tumor cell lines. A highly descriptive and predictive 3D-QSAR model was obtained through the calculation of alignment-independent descriptors (GRIND descriptors using ALMOND software. For a training set of 30 compounds, PLS analyses result in a three-component model which displays a squared correlation coefficient (r2 of 0.957 and a standard deviation of the error of calculation (SDEC of 0.116. Validation of this model was performed using leave-one-out, q2loo of 0.85, and leave-multiple-out. This model gives a remarkably high r2pred(0.66 for a test set of 10 compounds. Docking studies were performed to investigate the mode of interaction between β-carboline derivatives and the active site of the most probable anticancer receptor, polo-like kinase protein.

  11. Radioprotective Agents

    Science.gov (United States)

    1982-01-01

    claimed to be effective are gallic acid derivatives, eg, sodium gallate 12053-21-61 (295-297) and propyl gallate 1121-79-91 (298). p...inhibition of a-adrenergic receptors can be achieved through the use of the antiradiation agents 2-(5-aminopentylamino)ethanephos- phorothioic acid ...tissue was ap- preciated immediately as a potential medical set, and they were put to use en- thusiastically. Early workers did notice an erythematous

  12. Evidence for ecological causation of sexual dimorphism in a hummingbird.

    Science.gov (United States)

    Temeles, E J; Pan, I L; Brennan, J L; Horwitt, J N

    2000-07-21

    Unambiguous examples of ecological causes of animal sexual dimorphism are rare. Here we present evidence for ecological causation of sexual dimorphism in the bill morphology of a hummingbird, the purple-throated carib. This hummingbird is the sole pollinator of two Heliconia species whose flowers correspond to the bills of either males or females. Each sex feeds most quickly at the flower species approximating its bill dimensions, which supports the hypothesis that floral specialization has driven the evolution of bill dimorphism. Further evidence for ecological causation of sexual dimorphism was provided by a geographic replacement of one Heliconia species by the other and the subsequent development of a floral dimorphism, with one floral morph matching the bills of males and the other of females.

  13. Complement sentences - complementizers of causative-manipulative verbs

    Directory of Open Access Journals (Sweden)

    Alanović Milivoj B.

    2015-01-01

    Full Text Available This paper presents the key structural and semantic features of the complement sentences that have the primary function of direct or indirect objects of one type of causative verbs - causative-manipulative verbs. Since the syntactic literature frequently discusses the structural characteristics of the complement sentences, the main objective of this article is focused on the semantic diversity of this type of sentences. The goal of the article is to determine the dependence of the realized meaning of a sentence on the semantic type of the main verb. Although the conjunction da is a typical subordinator of these sentences, a series of communicative verbs allows the use of complement sentences with interrogative adverbs and pronouns in the function of conjunctions. [Projekat Ministarstva nauke Republike Srbije, br.178004: Standardni srpski jezik - sintaksička, semantička i pragmatička istraživanja

  14. Game of Objects: vicarious causation and multi-modal media

    Directory of Open Access Journals (Sweden)

    Aaron Pedinotti

    2013-09-01

    Full Text Available This paper applies philosopher Graham Harman's object-oriented theory of "vicarious causation" to an analysis of the multi-modal media phenomenon known as "Game of Thrones." Examining the manner in which George R.R. Martin's best-selling series of fantasy novels has been adapted into a board game, a video game, and a hit HBO television series, it uses the changes entailed by these processes to trace the contours of vicariously generative relations. In the course of the resulting analysis, it provides new suggestions concerning the eidetic dimensions of Harman's causal model, particularly with regard to causation in linear networks and in differing types of game systems.

  15. Causation at Different Levels: Tracking the Commitments of Mechanistic Explanations

    DEFF Research Database (Denmark)

    Fazekas, Peter; Kertész, Gergely

    2011-01-01

    This paper tracks the commitments of mechanistic explanations focusing on the relation between activities at different levels. It is pointed out that the mechanistic approach is inherently committed to identifying causal connections at higher levels with causal connections at lower levels. For th...... their autonomy at the same time than standard reductive accounts are, and that what mechanistic explanations are able to do at best is showing that downward causation does not exist....

  16. Synthesis and antimicrobial evaluation of two peptide LyeTx I derivatives modified with the chelating agent HYNIC for radiolabeling with technetium-{sup 99m}

    Energy Technology Data Exchange (ETDEWEB)

    Fuscaldi, Leonardo Lima; Santos, Daniel Moreira dos; Pinheiro, Natalia Gabriela Silva; Araujo, Raquel Silva; Barros, Andre Luis Branco de; Resende, Jarbas Magalhaes; Fernandes, Simone Odilia Antunes; Lima, Maria Elena de; Cardoso, Valbert Nascimento, E-mail: valbertncardoso@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Analises Clinicas Toxicologica

    2016-11-01

    Background: Current diagnostic methods and imaging techniques are not able to differentiate septic and aseptic inflammation. Thus, reliable methods are sought to provide this distinction and scintigraphic imaging is an interesting option, since it is based on physiological changes. In this context, radiolabeled antimicrobial peptides have been investigated as they accumulate in infectious sites instead of aseptic inflammation. The peptide LyeTx I, from the venom of Lycosa erythrognatha, has potent antimicrobial activity. Therefore, this study aimed to synthesize LyeTx I derivatives with the chelating compound HYNIC, to evaluate their antimicrobial activity and to radiolabel them with {sup 99m}Tc. Methods: Two LyeTx I derivatives, HYNIC-LyeTx I (N-terminal modification) and LyeTx I-K-HYNIC (C-terminal modification), were synthesized by Fmoc strategy and purified by RP-HPLC. The purified products were assessed by RP-HPLC and MALDI-ToF-MS analysis. Microbiological assays were performed against S. aureus (ATCC® 6538) and E. coli (ATCC® 10536) in liquid medium to calculate the MIC. The radiolabeling procedure of LyeTx I-K-HYNIC with {sub 99m}Tc was performed in the presence of co-ligands (tricine and EDDA) and reducing agent (SnCl{sub 2} . 2H{sub 2}O), and standardized taking into account the amount of peptide, reducing agent, pH and heating. Radiochemical purity analysis was performed by thin-layer chromatography on silica gel strips and the radiolabeled compound was assessed by RP-HPLC and radioactivity measurement of the collected fractions. Data were analyzed by ANOVA, followed by Tukey test (p-values < 0.05). Results: Both LyeTx I derivatives were suitably synthesized and purified, as shown by RP-HPLC and MALDI-ToF-MS analysis. The microbiological test showed that HYNIC-LyeTx I (N-terminal modification) did not inhibit bacterial growth, whereas LyeTx I-K-HYNIC (C-terminal modification) showed a MIC of 5.05 μmol. L−1 (S. aureus) and 10.10 μmol. L−1 (E. coli

  17. Causative factors and rehabilitation of patellar tendinopathy: A systematic review

    Directory of Open Access Journals (Sweden)

    Sanell Morgan

    2016-02-01

    Full Text Available Background: Patellar tendinopathy (PT is a common chronic pathology of the knee, with a high prevalence in athletes and the general population.Objectives: The objectives of this article were to systematically investigate all the evidence applicable to the intrinsic and extrinsic causative factors and rehabilitation of PT, and then integrate and link rehabilitation with the main causative factors identified.Method: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Various tools were used to evaluate the methodological quality of the eligible articles. Data were interpreted descriptively, and the causative factors and rehabilitation of PT were analysed.Results: Twenty studies were included in the review. The distinctive factor responsible for PT is the mechanical theory. Seven intrinsic and four extrinsic risk factors were identified, with the main intrinsic risk factors being muscle flexibility and strength, and extrinsic risk factors being acquisition and level of skills. PT can be treated with numerous different therapeutic modalities, although eccentric muscle training showed exceptional results. The intrinsic and extrinsic risk factors can only be transformed and reduced by rehabilitation, which is inevitable to improve PT pain and function.Conclusion: The essence of an integrated management protocol for PT is to identify the dominant contributing factors, whether intrinsic or extrinsic, and to reduce the load on the patellar tendon by modifying these factors by either rehabilitation intervention or direct modification of the equipment or environment to obtain a positive outcome towards pain management and function.

  18. Distribution territories and causative mechanisms of ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Rovira, A.; Grive, E.; Alvarez-Sabin, J. [Unidad de Resonancia Magnetica, Hospital Vall d' Hebron, Barcelona (Spain)

    2005-03-01

    Ischemic stroke prognosis, risk of recurrence, clinical assessment, and treatment decisions are influenced by stroke subtype (anatomic distribution and causative mechanism of infarction). Stroke subtype diagnosis is better achieved in the early phase of acute ischemia with the use of multimodal MR imaging. The pattern of brain lesions as shown by brain MR imaging can be classified according to a modified Oxfordshire method, based on the anatomic distribution of the infarcts into six groups: (1) total anterior circulation infarcts, (2) partial anterior circulation infarcts, (3) posterior circulation infarcts, (4) watershed infarcts, (5) centrum ovale infarcts, and (6) lacunar infarcts. The subtype of stroke according to its causative mechanism is based on the TOAST method, which classifies stroke into five major etiologic groups: (1) large-vessel atherosclerotic disease, (2) small-vessel atherosclerotic disease, (3) cardioembolic source, (4) other determined etiologies, and (5) undetermined or multiple possible etiologies. The different MR imaging patterns of acute ischemic brain lesions visualized using diffusion-weighted imaging and the pattern of vessel involvement demonstrated with MR angiography are essential factors that can suggest the most likely causative mechanism of infarction. This information may have an impact on decisions regarding therapy and the performance of additional diagnostic tests. (orig.)

  19. Downward Causation and the Neurobiology of Free Will

    CERN Document Server

    Murphy, Nancey; O’Connor, Timothy

    2009-01-01

    How is free will possible in the light of the physical and chemical underpinnings of brain activity and recent neurobiological experiments? How can the emergence of complexity in hierarchical systems such as the brain, based at the lower levels in physical interactions, lead to something like genuine free will? The nature of our understanding of free will in the light of present-day neuroscience is becoming increasingly important because of remarkable discoveries on the topic being made by neuroscientists at the present time, on the one hand, and its crucial importance for the way we view ourselves as human beings, on the other. A key tool in understanding how free will may arise in this context is the idea of downward causation in complex systems, happening coterminously with bottom up causation, to form an integral whole. Top-down causation is usually neglected, and is therefore emphasized in the other part of the book’s title. The concept is explored in depth, as are the ethical and legal implications of...

  20. Probability of causation: Implications for radiological protection and dose limitation

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.

    1987-05-01

    This report on the probability of causation of radiation-induced cancer is an attempt to bring together biology, chemistry, physics and statistics to calculate a value in the form of a ratio expressed as a percentage. In involves the interactions of numerous cancer risk factors, and all are fraught with technical difficulties and uncertainties. It is a computational approach to a societal problem that should be resolved in the political arena by men and women of government and law. But, it must be examined, because at the present, we have no reasonable method to explain the complexity of the mechanism of radiation-induced cancer and the probability of injury to an individual exposed in the past to ionizing radiation, and because society does not know how to compensate such a person who may have been injured by radiation, and particularly low-level radiation. Five questions are discussed that concern probability of causation of radiation-induced cancer. First, what is it and how can we best define the concept? Second, what are the methods of estimation and cancer causation? Third, what are the uncertainties involved? Fourth, what are the strengths and limitation of the computational approach? And fifth, what are the implications for radiological protection and dose-limitation?