WorldWideScience

Sample records for risperidone microspheres e-star

  1. Development of Risperidone PLGA Microspheres

    Directory of Open Access Journals (Sweden)

    Susan D’Souza

    2014-01-01

    Full Text Available The aim of this study was to design and evaluate biodegradable PLGA microspheres for sustained delivery of Risperidone, with an eventual goal of avoiding combination therapy for the treatment of schizophrenia. Two PLGA copolymers (50 : 50 and 75 : 25 were used to prepare four microsphere formulations of Risperidone. The microspheres were characterized by several in vitro techniques. In vivo studies in male Sprague-Dawley rats at 20 and 40 mg/kg doses revealed that all formulations exhibited an initial burst followed by sustained release of the active moiety. Additionally, formulations prepared with 50 : 50 PLGA had a shorter duration of action and lower cumulative AUC levels than the 75 : 25 PLGA microspheres. A simulation of multiple dosing at weekly or 15-day regimen revealed pulsatile behavior for all formulations with steady state being achieved by the second dose. Overall, the clinical use of Formulations A, B, C, or D will eliminate the need for combination oral therapy and reduce time to achieve steady state, with a smaller washout period upon cessation of therapy. Results of this study prove the suitability of using PLGA copolymers of varying composition and molecular weight to develop sustained release formulations that can tailor in vivo behavior and enhance pharmacological effectiveness of the drug.

  2. In vitro-in vivo correlation of parenteral risperidone polymeric microspheres.

    Science.gov (United States)

    Shen, Jie; Choi, Stephanie; Qu, Wen; Wang, Yan; Burgess, Diane J

    2015-11-28

    The objective of the present study was to determine whether an in vitro-in vivo correlation (IVIVC) can be established for polymeric microspheres that are equivalent in formulation composition but prepared with different manufacturing processes. Risperidone was chosen as a model therapeutic and poly(lactic-co-glycolic acid) (PLGA) with similar molecular weight as that used in the commercial product Risperdal® Consta® was used to prepare risperidone microspheres. Various manufacturing processes were investigated to produce the risperidone microspheres with similar drug loading (approx. 37%) but distinctly different physicochemical properties (e.g. porosity, particle size and particle size distribution). In vitro release of the risperidone microspheres was investigated using different release testing methods (such as sample-and-separate and USP apparatus 4). In vivo pharmacokinetic profiles of the risperidone microsphere formulations following intramuscular administration were determined using a rabbit model. Furthermore, the obtained pharmacokinetic profiles were deconvoluted using the Loo-Riegelman method and the calculated in vivo release was compared with the in vitro release of these microspheres. Level A IVIVCs were established and validated for the compositionally equivalent risperidone microspheres based on the in vitro release data obtained using USP apparatus 4. The developed IVIVCs demonstrated good predictability and were robust. These results showed that the developed USP apparatus 4 method was capable of discriminating PLGA microspheres that are equivalent in formulation composition but with manufacturing differences and predicting their in vivo performance in the investigated animal model.

  3. In Vitro-In Vivo Correlation of Parenteral Risperidone Polymeric Microspheres

    OpenAIRE

    2015-01-01

    The objective of the present study was to determine whether an in vitro-in vivo correlation (IVIVC) can be established for polymeric microspheres that are equivalent in formulation composition but prepared with different manufacturing processes. Risperidone was chosen as a model therapeutic and poly(lactic-co-glycolic acid) (PLGA) with similar molecular weight as that used in the commercial product Risperdal® Consta® was used to prepare risperidone microspheres. Various manufacturing processe...

  4. Sustained release of risperidone from biodegradable microspheres prepared by in-situ suspension-evaporation process.

    Science.gov (United States)

    An, Taekun; Choi, Juhyuen; Kim, Aram; Lee, Jin Ho; Nam, Yoonjin; Park, Junsung; Sun, Bo kyung; Suh, Hearan; Kim, Cherng-ju; Hwang, Sung-Joo

    2016-04-30

    Risperidone-loaded poly (D,L-lactide-co-glycolide) (PLGA) microspheres were prepared with a suspension-evaporation process with an aqueous suspension containing an in situ-formed aluminum hydroxide inorganic gel (SEP-AL process) and evaluated for encapsulation efficiency, particle size, surface morphology, glass transition temperature, in vitro drug release profile, and in vivo behavior. The SEP-AL microspheres were compared with conventional oil-in-water (O/W) emulsion solvent evaporation method using polyvinylalcohol (PVA) as an emulsifier (CP-PVA process). The microspheres were spherical in shape. DSC measurements showed that risperidone crystallinity was greatly reduced due to the homogeneous distribution of risperidone in PLGA microspheres. In vitro drug release profile from the microspheres showed a sigmoidal pattern of negligible initial burst up to 24h and minimal release (time-lag) for 7 days. After the lag phase, slow release took a place up to 25 days and then rapid release occurred sharply for 1 week. In vivo rat pharmacokinetic profile from the microspheres showed very low blood concentration level at the initial phase (up to 24h) followed by the latent phase up to 21 days. At the 3rd week, main phase started and the blood concentration of the drug increased up to the 5th week, and then gradually decreased. The risperidone-loaded PLGA microspheres produced by SEP-AL process showed excellent controlled release characteristics for the effective treatment of schizophrenia patients.

  5. Long acting risperidone in Australian patients with chronic schizophrenia: 24-month data from the e-STAR database

    Directory of Open Access Journals (Sweden)

    Lambert Tim

    2012-03-01

    Full Text Available Abstract Background This observational study was designed to collect treatment outcomes data in patients using the electronic Schizophrenia Treatment Adherence Registry (e-STAR. Methods Patients with schizophrenia or schizoaffective disorder in Australia who were prescribed risperidone long-acting injection (RLAI between 2003 and 2007 were assessed 12-months retrospectively, at baseline and 24-months prospectively at 3-monthly intervals. The intent-to-treat population, defined as all patients who received at least one dose of RLAI at baseline, was used for the efficacy and safety analyses. Results At total of 784 patients (74% with schizophrenia, 69.8% male with a mean age of 37.1 ± 12.5 years and 10.6 ± 9.5 years since diagnosis were included in this Australian cohort. A significant improvement in mean Clinical Global Impression - severity score was observed at 24-months (4.52 ± 1.04 at baseline, 3.56 ± 1.10 at 24-months. Most of this improvement was seen by 3-months and was also reflected in mean Global Assessment of Functioning score, which improved significantly at 24-months (42.9 ± 14.5 at baseline, 59 ± 15.4 at 24-months. For patients still receiving RLAI at 24-months there was an increase from a mean baseline RLAI dose of 26.4 ± 5 mg to 43.4 ± 15.7 mg. Sixty-six percent of patients discontinued RLAI before the 24-month period--this decreased to 46% once patients lost to follow-up were excluded. Conclusion Over the 24-month period, initiation of RLAI was associated with improved patient functioning and illness severity in patients with schizophrenia or schizoaffective disorder. Improved outcomes were observed early and sustained throughout the study. Trial Registration Clinical Trials Registration Number, NCT00283517.

  6. Risperidone

    Science.gov (United States)

    ... bipolar disorder (manic depressive disorder; a disease that causes episodes of depression, episodes of mania, and other abnormal moods). Risperidone is also used to treat behavior problems such as aggression, self-injury, and ... repetitive behavior, difficulty interacting with others, and problems ...

  7. Long-term outcomes in patients with schizophrenia treated with risperidone long-acting injection or oral antipsychotics in Spain: results from the electronic Schizophrenia Treatment Adherence Registry (e-STAR).

    Science.gov (United States)

    Olivares, J M; Rodriguez-Morales, A; Diels, J; Povey, M; Jacobs, A; Zhao, Z; Lam, A; Villalobos Vega, J C; Cuéllar, J Alonso; de Castro, F J Alberca; Quintero, C Morillo-Velarde; Martíin, J F Román; Domínguez, P Tabares; Ojeda, J L Prados; Cortés, S Sanz; Cala, F I Mata; Marín, C Gutiérrez; Castro, L Moyano; Duaso, M A Haza; Albarracín, J Requena; Vergara, G Narbona; Benítez, A Fernández; Cleries, F Mayoral; Pérez-Brian, J M García-Herrera; Aragón, A Bordallo; Navarro, J C Rodríguez; Biedma, J A Algarra; de Pedro, R Bravo; González, J F Delgado; López, M E Jaén; Moreno, H Díaz; López, J A Soto; Rodríguez, E Ojeda; de Hoyos, C Martínez; Sacristán, M Pardilla; Martín, M D Molina; Ballesteros, E Martín; Rodríguez, P A Sopelana; Menéndez, L Fernández; Rivas, R Santos; del Pino Cuadrado, P; Lauffer, J Correas; Solano, J J Rodríguez; Martínez, J M Fernández; Solano, F García; Rodríguez, P García-Lamberde; Rodríguez, J A Romero; Cano, T Rodríguez; Fortacin, M Ducaju; Lobeiras, J M Blanco; Sampedro, J M Piñeiro; Bravo, A Pérez; Pellicer, A Fernández; López, M D Alonso; Liste, J Fraga; Fernández, M Riobo; Losada, A Casas; Mendez, R Vazquez-Noguerol; Romero, S Agra; Blanco, J J Blanco; Bonaselt, I Tortajada; Mahia, M C García; del Valle, E Ferrer Gómez; Yañez, P Quiroga; Camarasa, M Gelabert; Alonso, J A Barbado; Mendez, G Florez; Feliz, F Doce; Lamela, M A López; Piñero, M Vega; Alvarado, P Fuentes; Gómez, I López; Martín, P Fadon; Gómez, J L Santos; López, A García; Jiménez, A Rodríguez; Nafs, A Escudero; Barquero, N Casas; Ortiz, R Fernández-Villamor; Noguera, J L Velez; Carrasco, P Ruiz; Muñoz, J Martín; Palma, M Masegoza; Hortelano, C Marín; Bonome, L Sánchez; Sevilla, J Sánchez; Juan, J M Mongil San; Ramos, J M García; Muñoz, J L Vallejo; Guisasola, J Elorza; Vazquez, L Santamaria; Guerras, F Campo; Nebot, F J Arrufat; Fernández, F J Baron; Nicolau, A L Palomo; Subirats, R Catala; Kidias, M Messays; Navarro, V Fabregat; García, B Frades; del Rosal, F Mejias; de Vicente Muñoz, T; Ballester, J Año; Lieb, P Malabia; Martel, A Delgado; Bea, E Roca; Joaquim, I Grau; Enjuanes, F Boatas; Piñol, M Bañuelos; Carbonell, E Fontova I; Muñoz, R Martín; Giribets, C Argila; Sans, L Albages; Blanco, A Serrano; Felipe, M Arcega; Muñoz, P González; Villanueva, A Pons; Arroyo, M Bernardo; Borri, R Coronas; Fallada, S Miret; Merola, M Celma; Rodon, E Parellada; Palmes, J R Pigem; Martínez, E Pérez; Catala, J Matarredona; Coca, A Sandoval; Ferrandiz, F Pascual; Paya, E Ferrandiz; Caballero, G Iturri; Bonet, A Franco; Figueras, J Fluvia; Pagador, P Moreno; Garibo, M Medina; Camo, V Pérez; Carrillo, C Sanz; Valero, C Pelegrin; Rebollo, F J Caro; García Campayo, J; Sala Ayma, J M Sala; Roig, M Martínez; de Uña Mateos, M A; Bertolin, R García; García, A Martín; Mazo, F Jiménez; Velasco, J L Galvez; Pérez, L Santa Maria; Casado, C Jiménez; Barba, J J Mancheño; Diaz, M Conde; Rubio, J P Alcon; Mandoli, A Soler; Herrero, A Uson; Martínez, A Rodríguez; Serrano, P Salgado; Rodríguez, E Nieto; Montesinos, J Segui; Macia, J Ferragud; Mateos Marcos, A Mateos; Soto, J V Pérez-Fuster; Dumont, M Verdaguer; Pagan, J Parra; Martínez, V Balanza; Santiuste de Pablos, M; Delgado, C Espinosa; Quiles, M D Martínez; López, F J Manzanera; Navarro, P Pozo; Torres, A Micol; Ingles, F J Martínez; Arias-Camison, J M Salmeron; Manzano, J C López; Peña, R Villanueva; Guitarte, G Petersen; Fontecilla, H Blasco; Romero, J Barjau; Gil, R Sanz; Lozano, J Marín; Adanez, L Donaire; Zarranz Herrera-Oria, I; Jiménez, J Pérez; Vaz, F Carrato; García, O Sanz; Anton, C Contreras; Casula, R Reixach; Hernandez, M C Natividad; Escabias, F Teba; Torresano, J Rodríguez; Pérez-Villamil, A Huidobro; Estevez, L; Figuero, M Aragües; Muñoz de Morales, A; Calvin, J L Rodríguez; Criado, M Delgado; Rodríguez, V Molina; Ambrosolio, E Balbo; Madera, P M Holgado; Alfaro, G Ponce; Vidal, M M Rojas; Valtuille, A García; Ruiz, O; Cabornero, G Lucas; Echevarria Martínez de Bujo, M; Mallen, M J Maicas; Puigros, J Santandreu; Martorell, A Liñana; Forteza, A Clar; Arrebola, E Rodríguez; Rodríguez de la Torre, M; Saiz, C G Anton; Bardolet I Casas, C; Linde, E Rodríguez; De Arce Cordon, R; Molina, E M Padial; Carazo, F J Ruiz; Romero, J J Muro; Cano, D Vico; Dorado, M Soria; Velazquez, S Campos; Sánchez, A J Rodríguez; Leon, S Ocio; Sánchez, K Pachas; Benitez, M Henry; Zugarramurai, A Intxausti; Contreras, M A; De la Varga González, M; Marín, P Barreiro; Robina, F Gómez; García, M Sánchez; Pérez, F J Otero; Bros, P Cubero; Gómez, A Carrillo; de Dios Molina Martín, J; Perera, J L Carrasco; Averbach, M C; Perera, J L Carrasco; Palancares, E Goenaga; Gallego de Dios, M T; Rojo, C Fernández; Iglesias, S Sánchez; Merino, M I Rubio; Mestre, N Prieto; Urdaniz, A Pérez; Sánchez, J M Martínez; Seco, R Gordo; Muñoz, J Franco; Agut, M Mateos; Lozano, M L Blanco; Herguedas, F Martín; Pena, A Torcal; García, J Vicente; Martínez, A Varona; Sanz Granado, O Sanz; Fernández, M A Medina; Canseco, J M Moran; López, P A Megia; Martín, M A Franco; Barrio, J A Espina; Ubago, J Giner; Bennassar, M Roca; Díez, J M Olivares; Fleta, J L Hernandez; Fortes, F Porras; López, C Arango; Medina, O; Alvarez, D Figuera; Roca, J M Peña; Valladolid, G Rubio; Tavera, J A Furquet; García-Castrillon Sales, J A; Llordes, I Batalla; Melgarejo, C Anchuistegui; Cañas de la Paz, F; Callol, V Vallés; García, M Bousoño; García, J Bobes; Leal, F J Vaz; Corrales, E Cáceres; Iglesias, E Sánchez; Gómez, M A Carreiras; Serrano, G García; Chillarón, E G Román; Aguado, F J Samino; Castillo, J J Molina; González, A González; Vázquez, J Gallardo; Peralvarez, M Bolivar; Diaz, M Rios; Mesa, M Ybarzabal; Artiles, F J Acosta; Chao, M Ajoy; Mesa, M Ybarzabal; del Rosario Santana, P; Escudero, M A García; Berenguer, M Molla; Llacer, J M Bonete; Berna, J A Juan; Ortiz, J Barragán; Pardell, L Tost; Hernández-Alvarez de Sotomayor, C; Méndez, M R Cejas; Garate, R Cabrera; Múgica, B Díaz; González, M Caballero; Domingo, J Pujol; Navarro, C Sáez; Vera, G Selva; Cuquerella, M A; Monzo, J Lonjedo; Boada, P Cervera; Pérez, M F Martín; Parrado, E Carrasco; Sánchez, J J Yañez; Fernández, J Calvo

    2009-06-01

    The electronic Schizophrenia Treatment Adherence Registry (e-STAR) is a prospective, observational study of patients with schizophrenia designed to evaluate long-term treatment outcomes in routine clinical practice. Parameters were assessed at baseline and at 3 month intervals for 2 years in patients initiated on risperidone long-acting injection (RLAI) (n=1345) or a new oral antipsychotic (AP) (n=277; 35.7% and 36.5% on risperidone and olanzapine, respectively) in Spain. Hospitalization prior to therapy was assessed by a retrospective chart review. At 24 months, treatment retention (81.8% for RLAI versus 63.4% for oral APs, p<0.0001) and reduction in Clinical Global Impression Severity scores (-1.14 for RLAI versus -0.94 for APs, p=0.0165) were significantly higher with RLAI. Compared to the pre-switch period, RLAI patients had greater reductions in the number (reduction of 0.37 stays per patient versus 0.2, p<0.05) and days (18.74 versus 13.02, p<0.01) of hospitalizations at 24 months than oral AP patients. This 2 year, prospective, observational study showed that, compared to oral antipsychotics, RLAI was associated with better treatment retention, greater improvement in clinical symptoms and functioning, and greater reduction in hospital stays and days in hospital in patients with schizophrenia. Improved treatment adherence, increased efficacy and reduced hospitalization with RLAI offer the opportunity of substantial therapeutic improvement in schizophrenia.

  8. 肌注利培酮微球与口服利培酮治疗精神分裂症疗效研究%Studies on the Eficacy of Intramuscular Risperidone Microspheres and Oral Risperidone in the Treatment of Schizophrenia

    Institute of Scientific and Technical Information of China (English)

    梁松新; 王秋琴; 麦以成; 邓良华

    2013-01-01

      目的探讨肌注利培酮微球与口服利培酮治疗精神分裂症的疗效,为临床选择药物提供依据.方法将80例精神分裂症患者随机分成肌注利培酮微球(RLAI)组及口服利培酮片组,治疗12周.在治疗第1、4、8、12周用阳性与阴性症状量表(PANSS)、临床疗效总评量表(CGI-SI)、不良反应量表(TESS)评定疗效和不良反应.结果两组PANSS总分及CGI-SI评分均比治疗前显著下降(P<0.01),与基线比较,PANSS评分自4周末以后均出现显著差异,两组疗效相当.RLAI组的不良反应明显低于口服利培酮片组(P<0.05).结论肌注利培酮微球与口服利培酮片治疗精神分裂症的疗效相当,RLAI组的不良反应较口服利培酮少而轻.肌注利培酮微球治疗精神分裂症安全有效,患者对治疗依从性比口服利培酮更好.%Objective To investigate the efficacy of intramuscular risperidone microspheres and oral risperidone in the treatment of schizophrenia, and to provide the basis for clinical drug of choice. Methods 80 cases of patients with schizophrenia were randomly divided into intramuscular risperidone microspheres(RLAI) group and the oral risperidone piece group, 12 weeks of treatment. Evaluate the efficacy and adverse reactions in the treatment of 1, 4, 8 and 12 weeks using the Positive and Negative Syndrome Scale(PANSS), the Clinical Global Impression(CGI-SI), adverse reactions Scale(TESS). Results The PANSS total score and CGI-SI score in both groups was significantly decreased(P<0.01) than before treatment. Compared with baseline, there are significant differences in the PANSS score after 4 weeks. Treatment efficiency in two group is very close to. The adverse drug reactions of RLAI group was significantly lower than the oral risperidone group(P<0.05). Conclusion The efficacy of intramuscular risperidone microspheres and oral risperidone tablets in the treatment of schizophrenia is very close to, The RLAI group adverse reactions are

  9. Analysis of the efficacy and safety of risperidone microsphere injection in treatment of schizophrenia%注射用利培酮微球治疗精神分裂症的疗效和安全性分析

    Institute of Scientific and Technical Information of China (English)

    张东升

    2015-01-01

    Objective:To investigate the efficacy and safety of risperidone microsphere injection in the treatment of schizophrenia. Methods:90 schizophrenia patients were selected.They were divided into the experimental group and the control group average. The control group were given risperidone tablets treatment,and the experimental group were treated with injection of risperidone treatment.Results:The total treatment efficiency and the quality of life score of the patients in the experimental group was significantly higher than those of the control group(P<0.05);the incidence of the adverse reactions of the experimental group was significantly lower than that of the control group(P<0.05).Conclusion:The curative effect of risperidone microspheres in the treatment of schizophrenia is significant and the safety is high.It can improve the quality of life of patients effectively.%目的:探讨注射用利培酮微球治疗精神分裂症的疗效和安全性。方法:收治精神分裂症患者90例,将其平均分为试验组和对照组,对照组采用利培酮片治疗,试验组采用注射利培酮微球治疗。结果:试验组治疗总有效率、生活质量评分明显高于对照组(P<0.05);试验组不良反应发生率明显低于对照组(P<0.05)。结论:注射用利培酮微球治疗精神分裂症的疗效显著且安全性高,有效改善了患者的生活质量。

  10. 注射用利培酮微球治疗精神分裂症的疗效和安全性%The Efficacy and Safety of Injectable Risperidone Microspheres for Treatment of Schizophrenia

    Institute of Scientific and Technical Information of China (English)

    杨建华

    2015-01-01

    目的:探讨注射利培酮微球治疗精神分裂症的疗效和安全性。方法将50例精神分裂症病患随机分组,给予病患注射用利培酮微球,在整个治疗过程中3、6、9、12、15周时,对照组采取口服利培酮片剂,以PANSS总分增减和不良反应数量为评定疗效的标准。结果实验组和对照组病患前后治疗PANSS总分的分值无差别变化无统计学意义,实验组与对照组在12周治疗的重点与基线相比PANSS总分有明显降低具有统计学意义(P<0.05)。35例精神分裂症病患在治疗前后血常规、血生化正常变化。实验组中大多数病患在接受25 mg/2周利培酮微球用药后病情得到控制或改善,无明显的不良反应。结论对精神分裂病患以利培酮微球注射治疗3周末即起效,治疗效果与口服利培酮片的相当。注射利培酮微球具有疗效稳定、高安全性的特点。%Objective To efficacy and safety study risperidone microsphere injection in the treatment of schizophrenia.Methods 50 cases of schizophrenic patients randomized,give patient risperidone long-acting injection,in the whole course of treatment,3,6,9,12,15 weeks,the control group took oral risperidone tablets to increase or decrease the number of total PANSS score,and adverse reaction for curative effect standard.ResultsThe experimental group and the control group before and after treatment of PANSS disease score score did not change no significant difference,the experimental group and the control group in the 12 week of treatment compared with baseline PANSS scores of key significantly decreased with statistical significance(P<0.05). 35 cases of schizophrenic patients before and after treatment of blood routine,blood biochemical changes in the normal. The majority of patients in the experimental group in an 25 mg/2 weeks risperidone microsphere obtained control or improve the disease after treatment,no significant adverse reactions

  11. Microspheres

    Science.gov (United States)

    1990-01-01

    Vital information on a person's physical condition can be obtained by identifying and counting the population of T-cells and B-cells, lymphocytes of the same shape and size that help the immune system protect the body from the invasion of disease. The late Dr. Alan Rembaum developed a method for identifying the cells. The method involved tagging the T-cells and B-cells with microspheres of different fluorescent color. Microspheres, which have fluorescent dye embedded in them, are chemically treated so that they can link with antibodies. With the help of a complex antibody/antigen reaction, the microspheres bind themselves to specific 'targets,' in this case the T-cells or B-cells. Each group of cells can then be analyzed by a photoelectronic instrument at different wavelengths emitted by the fluorescent dyes. Same concept was applied to the separation of cancer cells from normal cells. Microspheres were also used to conduct many other research projects. Under a patent license Magsphere, Inc. is producing a wide spectrum of microspheres on a large scale and selling them worldwide for various applications.

  12. Risperidone Injection

    Science.gov (United States)

    ... control slow movements or shuffling walk falling painful erection of the penis that lasts for hours Risperidone extended-release injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.If you experience a ...

  13. A reproducible accelerated in vitro release testing method for PLGA microspheres.

    Science.gov (United States)

    Shen, Jie; Lee, Kyulim; Choi, Stephanie; Qu, Wen; Wang, Yan; Burgess, Diane J

    2016-02-10

    The objective of the present study was to develop a discriminatory and reproducible accelerated in vitro release method for long-acting PLGA microspheres with inner structure/porosity differences. Risperidone was chosen as a model drug. Qualitatively and quantitatively equivalent PLGA microspheres with different inner structure/porosity were obtained using different manufacturing processes. Physicochemical properties as well as degradation profiles of the prepared microspheres were investigated. Furthermore, in vitro release testing of the prepared risperidone microspheres was performed using the most common in vitro release methods (i.e., sample-and-separate and flow through) for this type of product. The obtained compositionally equivalent risperidone microspheres had similar drug loading but different inner structure/porosity. When microsphere particle size appeared similar, porous risperidone microspheres showed faster microsphere degradation and drug release compared with less porous microspheres. Both in vitro release methods investigated were able to differentiate risperidone microsphere formulations with differences in porosity under real-time (37 °C) and accelerated (45 °C) testing conditions. Notably, only the accelerated USP apparatus 4 method showed good reproducibility for highly porous risperidone microspheres. These results indicated that the accelerated USP apparatus 4 method is an appropriate fast quality control tool for long-acting PLGA microspheres (even with porous structures).

  14. Interpreting serum risperidone concentrations.

    Science.gov (United States)

    Boerth, Joel M; Caley, Charles F; Goethe, John W

    2005-02-01

    Risperidone is an atypical antipsychotic commonly used for treatment of schizophrenia and other psychotic disorders. Although therapeutic drug monitoring is not routine for any of the atypical antipsychotics, serum antipsychotic concentrations are measured routinely to assess treatment nonadherence. In humans, risperidone is metabolized by cytochrome P450 2D6 to 9-hydroxyrisperidone; together these constitute the active moiety. Dose-proportional increases in serum concentrations have not been reported for the parent drug, but have been reported for 9-hydroxyrisperidone and the active moiety (i.e., the combined concentrations of risperidone and 9-hydroxyrisperidone). We describe a 34-year-old Caucasian man of Sicilian descent with a history of schizophrenia, disorganized type. He was suspected to be noncompliant with his risperidone therapy. Initially, active moiety risperidone concentrations increased linearly with prescribed dosage increases. However, with continued increases, active moiety concentrations adjusted downward and remained 17-36% below anticipated levels. We propose a method for estimating target active moiety concentrations of risperidone based on dosage-a method that may be used to guide clinicians in assessing nonadherence to risperidone treatment.

  15. Polymeric microspheres

    Science.gov (United States)

    Walt, David R.; Mandal, Tarun K.; Fleming, Michael S.

    2004-04-13

    The invention features core-shell microsphere compositions, hollow polymeric microspheres, and methods for making the microspheres. The microspheres are characterized as having a polymeric shell with consistent shell thickness.

  16. 注射用利培酮微球与非经典抗精神病药治疗精神分裂症的对照研究%A comparative study between long-acting risperidone microsphere injection for treatment of patients with schizophrenia

    Institute of Scientific and Technical Information of China (English)

    谷德康; 杨楠; 白录东

    2010-01-01

    Objective To investigate clinical efficacy and side effects of long-acting risperidone microsphere injection for treatment of patients with schizophrenia. Methods A total of 82 patients with schizophrenia were randomly divided into two groups,study group with long-acting risperidone microsphere injection and control group with atypical antipsychotics treatment for 24 weeks. The Positive and Negative Syndrome Scale (PANSS),The Personal and Social Performance (PSP) and Treatment Emergent Symptoms Scale (TESS) were used to evaluate efficacy and adverse effects of treatment at the end of 1st ,2nd,4th, 12nd and 24th week. Results The therapeutic efficacy in control group was similar to that in study group,and there was no significant difference between the two groups (P> 0.05 ). But the therapeutic efficacy in study group was better than that in control group at the end of the 4nd week (P<0.05 ) , and study group was more likely to improve social function(P < 0. 05 ). Incidence of adverse effects in study group was lower than that in control group , but the difference was not significant (P >0.05 ). The incidence of akathisia symptom in study group was higher than that in control group,but the difference was not significant (P>0.05). The incidence of drowsiness symptom in study group was significantly lower than that in control group(P<0.05 ). Conclusion Long-acting risperidone microsphere injection is as effective as atypical antipsychotics for treatment of patients with schizophrenia, but it has better efficacy in improving social function of the schizophrenia with lower side effects.%目的 探讨注射用利培酮微球治疗精神分裂症的疗效和安全性.方法 符合诊断标准的82名精神分裂症患者分成2组,分别给予注射用利培酮微球和非经典抗精神病药物利培酮、喹硫平、奥氮平治疗24周.于治疗前及治疗后2,4,12,24周末分别采用阳性与阴性症状量表(PANSS)、个体和社会功能量表(PSP)

  17. Polyacrolein microspheres

    Science.gov (United States)

    Rembaum, Alan (Inventor)

    1987-01-01

    Microspheres of acrolein homopolymers and copolymer with hydrophillic comonomers such as methacrylic acid and/or hydroxyethylmethacrylate are prepared by cobalt gamma irradiation of dilute aqueous solutions of the monomers in presence of suspending agents, especially alkyl sulfates such as sodium dodecyl sulfate. Amine or hydroxyl modification is achieved by forming adducts with diamines or alkanol amines. Carboxyl modification is effected by oxidation with peroxides. Pharmaceuticals or other aldehyde reactive materials can be coupled to the microspheres. The microspheres directly form antibody adducts without agglomeration.

  18. Postmortem Femoral Blood Concentrations of Risperidone

    DEFF Research Database (Denmark)

    Linnet, Kristian; Johansen, Sys Stybe

    2014-01-01

    Postmortem femoral blood concentrations of the antipsychotic drug risperidone and the active metabolite 9-hydroxyrisperidone were determined by an achiral LC-MS/MS method in 38 cases. The cause of death was classified as unrelated to risperidone in 30 cases, in which the sum of the concentration ...

  19. Fluorescent microspheres

    Science.gov (United States)

    Rembaum, A.

    1978-01-01

    Latex particles with attached antibodies have potential biochemical and environmental applications. Human red blood cells and lymphocytes have been labeled with fluorescent microspheres by either direct or indirect immunological technique. Immunolatex spheres can also be used for detecting and localizing specific cell surface receptors. Hormones and toxins may also be bondable.

  20. Risperidone for Aggressive Behavior in ADHD

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-05-01

    Full Text Available The effects of risperidone augmentation for treatment-resistant aggression in children with ADHD were evaluated in a placebo-controlled pilot study at the University of Miami Miller School of Medicine, FL.

  1. Evolutionary status of isolated B[e] stars

    CERN Document Server

    Lee, Chien-De; Liu, S Y

    2016-01-01

    Aims. We study a sample of eight B[e] stars with uncertain evolutionary status to shed light on the origin of their circumstellar dust. Methods. We performed a diagnostic analysis on the spectral energy distribution beyond infrared wavelengths, and conducted a census of neighboring region of each target to ascertain its evolutionary status. Results. In comparison to pre-main sequence Herbig stars, these B[e] stars show equally substantial excess emission in the near-infrared, indicative of existence of warm dust, but much reduced excess at longer wavelengths, so the dusty envelopes should be compact in size. Isolation from star-forming regions excludes the possibility of their pre-main sequence status. Six of our targets, including HD 50138, HD 45677, CD-245721, CD-49 3441, MWC 623, and HD 85567, have been previously considered as FS CMa stars, whereas HD 181615/6 and HD 98922 are added to the sample by this work. We argue that the circumstellar grains of these isolated B[e] stars, already evolved beyond the ...

  2. Risperidone-induced symptomatic hyperprolactinaemia in adolescents.

    Science.gov (United States)

    Holzer, Laurent; Eap, Chin B

    2006-04-01

    Studies performed in adult patients unambiguously demonstrate a marked effect of risperidone on prolactin blood levels, with possible clinical effects related to hyperprolactinemia, such as gynecomastia and galactorrhea. However, the largest study performed in children and adolescents showed a weak effect of risperidone on prolactin concentrations during short-term treatment and a negligible effect during long-term treatment, which was probably because of the relatively low dosages of risperidone used [approximately 0.04 mg/(kg x d)]. Among the 10 psychotic adolescents treated with risperidone in our unit, we had 3 cases of gynecomastia in 3 male patients and 2 cases of galactorrhea in 2 female patients. The prolactin blood levels in these cases and in 3 other patients without apparent prolactin-related side effects were all above the normal range (median, 59 ng/mL; range, 30-123 ng/mL). Thus, risperidone administered to adolescents at doses commonly used for the treatment of psychotic symptoms can strongly increase prolactin levels, with clinical consequences such as gynecomastia and/or galactorrhea. Given that the long-term effects of antipsychotic drug-induced hyperprolactinemia are not well documented, especially regarding osteopenia, infertility, growth, and pubertal delay, risperidone should be administered with caution to children and adolescents.

  3. Hybrid microspheres

    Science.gov (United States)

    Rembaum, Alan (Inventor); Yen, Richard C. K. (Inventor)

    1985-01-01

    Substrates, particularly inert synthetic organic resin beads (10) or sheet (12) such as polystyrene are coated with a covalently bound layer (24) of polyacrolein by irradiation a solution (14) of acrolein or other aldehyde with high intensity radiation. Individual microspheres (22) are formed which attach to the surface to form the aldehyde containing layer (24). The aldehyde groups can be converted to other functional groups by reaction with materials such as hydroxylamine. Adducts of proteins such as antibodies or enzymes can be formed by direct reaction with the surface aldehyde groups.

  4. Tracking the effect of microspheres size on the drug release from a microsphere/sucrose acetate isobutyrate (SAIB) hybrid depot in vitro and in vivo.

    Science.gov (United States)

    Lin, Xia; Wang, Jing; Xu, Yuhong; Tang, Xing; Chen, Jian; Zhang, Yu; Zhang, Yan; Yang, Ziyi

    2016-09-01

    The effects of particle size of microspheres on the drug release from a microsphere/sucrose acetate isobutyrate (SAIB) hybrid depot (m-SAIB) was investigated to develop a long-term sustained release drug delivery system with low burst release both in vitro and in vivo. A model drug, risperidone, was first encapsulated into PLGA microspheres with different particle sizes using conventional emulsification and membrane emulsification methods. The m-SAIB was prepared by dispersing the risperidone-microspheres in the SAIB depot. The drug release from m-SAIB was double controlled by the drug diffusion from the microspheres into SAIB matrix and the drug diffusion from the SAIB matrix into the medium. Large microspheres (18.95 ± 18.88 µm) prepared by the conventional homogenization method exhibited porous interior structure, which contributed to the increased drug diffusion rate from microspheres into SAIB matrix. Consequently, m-SAIB containing such microspheres showed rapid initial drug release (Cmax = 110.1 ±54.2 ng/ml) and subsequent slow drug release (Cs(4-54d)= 2.7 ± 0.8 ng/ml) in vivo. Small microspheres (5.91 ± 2.24 µm) showed dense interior structure with a decreased drug diffusion rate from microspheres into SAIB matrix. The initial drug release from the corresponding m-SAIB was significantly decreased (Cmax = 40.9 ± 13.7 ng/ml), whereas the drug release rate from 4 to 54 d was increased (Cs(4-54d)=4.1 ± 1.0 ng/ml). By further decreasing the size of microspheres to 3.38 ± 0.70 µm, the drug diffusion surface area was increased, which subsequently increased the drug release from the m-SAIB. These results demonstrate that drug release from the m-SAIB can be tailored by varying the size of microspheres to reduce the in vivo burst release of SAIB system alone.

  5. RISPERIDONE IN INDIAN PATIENTS WITH SCHIZOPHRENIA

    Science.gov (United States)

    Agarwal, A.K.; Bashyam, V.S.P; Channabasavanna, S.M.; Dhavale, H.S.; Khan, M.A.M.; Khanna, Sumant; Pradhan, P.V.; Katiyar, M.; Rajkumar, R.; Niazi, Faiz R.; Jalali, R.K.; Gowrishankar, R.; Mishra, S.K.; Sood, O.P.

    1998-01-01

    Conventional antipsychotic agents are not effective against negative symptoms of schizophrenia and are also noted for their extrapyramidal side effects. Risperidone is a noval antipsychotic agent whose dual antagonism of dopamine and serotonin receptors is believed to underlie its efficacy against negative symptoms and the low incidence of extrapyramidal side effects. An open, non-comparative study of seven weeks duration was performed to evaluate risperidone in the treatment of schizophrenia in Indian patients. Previous antipsychotic therapy was discontinued for a week before risperidone therapy was initiated. At the end of six weeks of risperidone therapy, clinical improvement (≥ 20% reduction in total score on positive and negative syndrome scale for schizophrenia (PANSS;; was shown by 128 (87.7%) of the 146 evaluable patients. Statistically significant reduction (p < 0.05) occurred in the total score of this scale and in the subscale scores for positive, negative and general psychopathology symptoms and in the clinical global impression severity score. The number of patients with adverse experiences were 108 (65.5%) at baseline and 120 (72.7%) at the end of risperidone therapy. Extrapyramidal symptoms, seen in 65 (39.4%) patients compared to 22 (13.3%) patients at baseline, were largely mild to moderate in intensity. PMID:21494480

  6. Risperidone associated paralytic ileus in schizophrenia

    Directory of Open Access Journals (Sweden)

    Parthasarathy Ramamourthy

    2013-01-01

    Full Text Available A 32-year-old man, diagnosed with catatonic schizophrenia, was treated with risperidone and lorazepam in the general hospital psychiatry setup. He developed signs of intestinal obstruction, which was diagnosed as paralytic ileus and was treated conservatively along with stopping the offending drug. Risperidone is said to be devoid of anticholinergic side effects, but prevalence of these varies from 7% to 13% in patients receiving treatment for schizophrenia. Constipation has been reported but fatal adverse effect like paralytic ileus with risperidone is rarely reported. Timely diagnosis can save the need for surgical interventions and fatal complications. This predisposition in schizophrenia could be due to neurodevelopmentally shared abnormality of brain and gut nervous system.

  7. Gynecomastia with risperidone-fluoxetine combination.

    Science.gov (United States)

    Benazzi, F

    1999-01-01

    Gynecomastia (breast enlargement) is a side effect of neuroleptic antipsychotic drugs, related to prolactin elevation caused by dopamine D2 receptor blockade (Richelson, 1996). The atypical antipsychotic risperidone is less likely to cause gynecomastia at low doses (Casey, 1996). It can cause a dose-dependent increase in serum prolactin concentration (Peuskens, 1995), by blocking dopamine D2 receptors (Richelson, 1996). I would like to describe a patient who did not have gynecomastia with risperidone at a dose of 3 mg/day, but had it when risperidone, at a dose of 0.5 mg/day, was combined with fluoxetine. A MEDLINE search failed to find any reports about such an interaction.

  8. Disk formation in oblate B[e] stars

    CERN Document Server

    Araya, I; Curé, M

    2016-01-01

    We investigate the possible role of line-driven winds in the circumstellar envelope in B[e] stars, mainly the role of the $\\Omega$-slow wind solution, which is characterized by a slower terminal velocity and higher mass-loss rate, in comparison with the standard (m-CAK) wind solution. In this work, we assume two scenarios: 1) a spherically symmetric star and 2) a scenario that considers the oblate shape, considering only the oblate correction factor. For certain values of the line force parameters (according to previous works), we obtain in both scenarios a density contrast $\\gtrsim10^{2}$ between equatorial and polar densities, characterized for a fast polar wind and a slow and denser wind when the $\\Omega$-slow wind solution is obtained. All this properties are enhanced when the oblate correction factor is included in our calculations.

  9. Risperidone for the treatment of delusional disorder.

    Science.gov (United States)

    Fear, Christopher F; Libretto, Susan E

    2002-01-01

    The overlap between diagnostic criteria for schizophrenia and delusional disorder (DD) may cause diagnostic confusion. This is important if response to treatment differs. Risperidone, an atypical antipsychotic, is established in the treatment of schizophrenia, although less so in other psychotic conditions. We report the case of a woman who developed DD, persecutory type, at the age of 50 years. Treatment with sulpiride 200-800 mg daily caused side-effects of drowsiness and 'hangover' and, consequently, non-compliance. Written informed consent was gained for a 24-week, randomized, double-blind, placebo-controlled, crossover trial of risperidone, initiated at 1 mg daily and increasing to 2 mg daily. Significant improvement was found, as assessed by the Brief Psychiatric Rating Scale, Positive and Negative Symptom Schedule and Maudsley Assessment of Delusions Schedule. We believe that this is the first case study reporting the resolution of persecutory DD with risperidone. A controlled clinical trial of risperidone in the treatment of patients with DD is warranted. (Int J Psych Clin Pract 2002; 6: 113-116).

  10. Risperidone versus other atypical antipsychotics for schizophrenia

    Science.gov (United States)

    Komossa, Katja; Rummel-Kluge, Christine; Schwarz, Sandra; Schmid, Franziska; Hunger, Heike; Kissling, Werner; Leucht, Stefan

    2014-01-01

    Background In many countries of the industrialised world second-generation (“atypical”) antipsychotics (SGAs) have become the first line drug treatment for people with schizophrenia. The question as to whether and if so how much the effects of the various SGAs differ is a matter of debate. In this review we examined how the efficacy and tolerability of risperidone differs from that of other SGAs. Objectives To evaluate the effects of risperidone compared with other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychosis. Search methods 1. Electronic searching We searched the Cochrane Schizophrenia Group Trials Register (April 2007) which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO. 2. Reference searching We inspected the references of all identified studies for more trials. 3. Personal contact We contacted the first author of each included study for missing information. 4. Drug companies We contacted the manufacturers of all atypical antipsychotics included for additional data. Selection criteria We included all randomised, blinded trials comparing oral risperidone with oral forms of amisulpride, aripiprazole, clozapine, olanzapine, quetiapine, sertindole, ziprasidone or zotepine in people with schizophrenia or schizophrenia-like psychosis. Data collection and analysis We extracted data independently. For dichotomous data we calculated risk ratio (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. We calculated numbers needed to treat/harm (NNT/NNH) where appropriate. For continuous data, we calculated mean differences (MD), again based on a random-effects model. Main results The review currently includes 45 blinded RCTs with 7760 participants. The number of RCTs available for each comparison varied: four studies compared risperidone with amisulpride, two with aripiprazole, 11 with clozapine, 23 with olanzapine, eleven with

  11. RISPERIDONE - INDUCED TARDIVE DYSKINESIA : CASE REPORT AND REVIEW OF LITERATURE

    OpenAIRE

    Kumar, P.N. Suresh; Andrade, Chittaranjan

    2001-01-01

    Risperidone is an atypical antipsychotic with broad spectrum of antipsychotic activity and lower potential for extrapyramidal side effects at therapeutic doses. This case report illustrates the development of tardive dyskinesia with therapeutic dose of risperidone in a paranoid schizophrenic patient who was not on any antipsychotic medication previously.

  12. Euprolactinemic gynecomastia and galactorrhea with risperidone-fluvoxamine combination.

    Science.gov (United States)

    Pratheesh, P J; Praharaj, Samir Kumar; Srivastava, Ashish

    2011-01-01

    Risperidone is associated with hyperprolactinemia and its consequent symptoms such as gynecomastia, galactorrhea and sexual dysfunction in adults, and less so in adolescents. Rarely, serotonin reuptake inhibitors are also associated with such adverse effects. We report a case of gynecomastia and galactorrhea in an adolescent male while on a combination of risperidone and fluvoxamine, although the serum prolactin was within normal range.

  13. Making Polymeric Microspheres

    Science.gov (United States)

    Rhim, Won-Kyu; Hyson, Michael T.; Chung, Sang-Kun; Colvin, Michael S.; Chang, Manchium

    1989-01-01

    Combination of advanced techniques yields uniform particles for biomedical applications. Process combines ink-jet and irradiation/freeze-polymerization techniques to make polymeric microspheres of uniform size in diameters from 100 to 400 micrometer. Microspheres used in chromatography, cell sorting, cell labeling, and manufacture of pharmaceutical materials.

  14. Polymeric Microspheres for Medical Applications

    Directory of Open Access Journals (Sweden)

    Ketie Saralidze

    2010-06-01

    Full Text Available Synthetic polymeric microspheres find application in a wide range of medical applications. Among other applications, microspheres are being used as bulking agents, embolic- or drug-delivery particles. The exact composition of the spheres varies with the application and therefore a large array of materials has been used to produce microspheres. In this review, the relation between microsphere synthesis and application is discussed for a number of microspheres that are used for different treatment strategies.

  15. Discovering risperidone: the LSD model of psychopathology.

    Science.gov (United States)

    Colpaert, Francis C

    2003-04-01

    In the 1970s and 1980s, Janssen Pharmaceutica Research, which had a broad interest in central nervous system disorders and nurtured intellectual freedom, developed original, and at times heretical, concepts. It took decades for the scientific community to endorse some of these concepts. Among them were such notions as an elementary particle of behaviour, the introduction of response quality in receptor theory, and the idea that tolerance does not develop to opioids. These concepts enabled the discovery of the antipsychotic risperidone, a unique full antagonist of the interoceptive effects of LSD.

  16. Prolactin levels and adverse events in patients treated with risperidone.

    Science.gov (United States)

    Kleinberg, D L; Davis, J M; de Coster, R; Van Baelen, B; Brecher, M

    1999-02-01

    Hyperprolactinemia is a common clinical disorder that may lead to sexual dysfunction or galactorrhea. It may arise from a variety of etiologies, including the use of antipsychotic agents, presumably because of a dopamine receptor blockade. This analysis was designed to characterize the relationship between risperidone, serum prolactin levels, and possible clinical sequelae. All data from randomized, double-blind studies of risperidone in patients with chronic schizophrenia were analyzed. The two largest studies (the North American and multinational trials) included 841 patients (259 women, 582 men) with paired prolactin level data and 1,884 patients (554 women, 1,330 men) with data on six adverse events possibly associated with increased prolactin levels (amenorrhea, galactorrhea, and decreased libido in women; erectile dysfunction, ejaculatory dysfunction, gynecomastia, and decreased libido in men). Both risperidone and haloperidol produced dose-related increases in plasma prolactin levels in men and women. Among women, the risperidone dose was not correlated with adverse events, nor were the adverse events correlated with endpoint prolactin levels. Among men, the incidence of adverse events was positively correlated with risperidone dose; however, at risperidone doses of 4 to 10 mg/day the incidence of adverse events was not significantly higher than that observed in patients receiving placebo. Furthermore, adverse events in men were unrelated to plasma prolactin levels. Risperidone-associated increase in serum prolactin levels was not significantly correlated to the emergence of possible prolactin-related side effects.

  17. P-glycoprotein interaction with risperidone and 9-OH-risperidone studied in vitro, in knock-out mice and in drug-drug interaction experiments

    DEFF Research Database (Denmark)

    Ejsing, Thomas B.; Pedersen, Anne D.; Linnet, Kristian

    2005-01-01

    P-glycoprotein, risperidone, nortriptyline, cyclosporine A, drug-drug interaction, blood-brain barrier, knock-out mice......P-glycoprotein, risperidone, nortriptyline, cyclosporine A, drug-drug interaction, blood-brain barrier, knock-out mice...

  18. Microsphere Insulation Panels

    Science.gov (United States)

    Mohling, R.; Allen, M.; Baumgartner, R.

    2006-01-01

    Microsphere insulation panels (MIPs) have been developed as lightweight, longlasting replacements for the foam and vacuum-jacketed systems heretofore used for thermally insulating cryogenic vessels and transfer ducts. The microsphere core material of a typical MIP consists of hollow glass bubbles, which have a combination of advantageous mechanical, chemical, and thermal-insulation properties heretofore available only separately in different materials. In particular, a core filling of glass microspheres has high crush strength and low density, is noncombustible, and performs well in soft vacuum.

  19. Organic aerogel microspheres

    Science.gov (United States)

    Mayer, Steven T.; Kong, Fung-Ming; Pekala, Richard W.; Kaschmitter, James L.

    1999-01-01

    Organic aerogel microspheres which can be used in capacitors, batteries, thermal insulation, adsorption/filtration media, and chromatographic packings, having diameters ranging from about 1 micron to about 3 mm. The microspheres can be pyrolyzed to form carbon aerogel microspheres. This method involves stirring the aqueous organic phase in mineral oil at elevated temperature until the dispersed organic phase polymerizes and forms nonsticky gel spheres. The size of the microspheres depends on the collision rate of the liquid droplets and the reaction rate of the monomers from which the aqueous solution is formed. The collision rate is governed by the volume ratio of the aqueous solution to the mineral oil and the shear rate, while the reaction rate is governed by the chemical formulation and the curing temperature.

  20. Organic aerogel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, S.T.; Kong, F.M.; Pekala, R.W.; Kaschmitter, J.L.

    1999-06-01

    Organic aerogel microspheres are disclosed which can be used in capacitors, batteries, thermal insulation, adsorption/filtration media, and chromatographic packings, having diameters ranging from about 1 micron to about 3 mm. The microspheres can be pyrolyzed to form carbon aerogel microspheres. This method involves stirring the aqueous organic phase in mineral oil at elevated temperature until the dispersed organic phase polymerizes and forms nonstick gel spheres. The size of the microspheres depends on the collision rate of the liquid droplets and the reaction rate of the monomers from which the aqueous solution is formed. The collision rate is governed by the volume ratio of the aqueous solution to the mineral oil and the shear rate, while the reaction rate is governed by the chemical formulation and the curing temperature.

  1. Peripheral Edema Occurring during Treatment with Risperidone Combined with Citalopram

    Directory of Open Access Journals (Sweden)

    Seyed Hamzeh Hosseini

    2012-01-01

    Full Text Available An 80-year-old female presented with symptoms of depression, worthlessness, hopelessness, loss of energy, insomnia, impatience, and forgetfulness associated with persecutory delusion that had begun about one year before her visit. She was diagnosed with major depression with psychotic signs and began treatment with risperidone (2 mg/night and citalopram (20 mg/day. After 20 days, she returned and reported partial improvement in her symptoms, although she had developed severe swelling of the hands and feet. The results of liver and renal function tests and rheumatologic tests were found to be within normal limits. Risperidone was discontinued for a week, and the swelling resolved completely. Risperidone was then administered again, and the swelling returned so that the patient had to discontinue taking the drug. The reappearance of edema on rechallenge is strong evidence implicating risperidone as the cause of the swelling.

  2. Risperidone treatment increases CB1 receptor binding in rat brain

    DEFF Research Database (Denmark)

    Secher, Anna; Husum, Henriette; Holst, Birgitte

    2010-01-01

    BACKGROUND/AIMS: Body weight gain is a common side effect of treatment with antipsychotics, but the mechanisms underlying this weight gain are unknown. Several factors may be involved in antipsychotic-induced body weight gain including the cannabinoid receptor 1 (CB(1)), the serotonin receptor 2C...... positively correlated with visceral fat mass. Risperidone treatment increased CB(1) receptor binding in the arcuate nucleus (40%), hippocampus (25-30%) and amygdala (35%) without concurrent alterations in the CB(1) receptor mRNA. Risperidone treatment increased adiponectin mRNA. CONCLUSION: The present study...... showed that risperidone treatment altered CB(1) receptor binding in the rat brain. Risperidone-induced adiposity and metabolic dysfunction in the clinic may be explained by increased CB(1) receptor density in brain regions involved in appetite and regulation of metabolic function....

  3. A Case of Priapism with Risperidone

    Directory of Open Access Journals (Sweden)

    Almari Ginory

    2014-01-01

    Full Text Available Priapism is a urologic emergency defined as a prolonged, possibly painful, penile erection. There are several known causes of priapism including psychotropic medications. One of the mechanisms by which antipsychotics are believed to induce priapism is through alpha-1 antagonism. This is case of a 50-year-old male with a history of schizophrenia with previous priapism related to trazodone, who presents with new onset priapism associated with risperidone. In this case, the treatment of priapism includes discontinuation of the offending agent and drainage of the corpus cavernosum twice along with intracavernosal phenylephrine injections. It is important to educate patients on priapism as a possible side effect of medications. It is also important to consider previous episodes of medication-induced priapism when prescribing psychotropic medications as this may increase the patient’s future risk of priapism.

  4. Establishment of the sterility test method for risperidone for depot suspension%注射用利培酮微球无菌检查法的建立

    Institute of Scientific and Technical Information of China (English)

    王似锦; 刘文杰; 高春

    2013-01-01

    Objective:To establish the method of sterility test for risperidone for depot suspension.Methods:Sterility test of risperidone for depot suspension was carried out using the technique of direct inoculation,and the validation test was accomplished according to CP 2010.Results:As a result of the method validation of sterility test,all the test strains grew well.The established method was suitable for the sterility test of risperidone for depot suspension.Conclusion:Sterility test of risperidone for depot suspension is composed of outer sterility test and inner sterility test.Dimethyl sulfoxide (DMSO) can be used for inner sterility test as a solvent because it can dissolve and break the microspheres.%目的:建立注射用利培酮微球的无菌检查法.方法:采用直接接种法进行利培酮微球的无菌检查,并按照《中华人民共和国药典》的要求进行了方法学验证试验研究.结果:经过方法学验证,各验证菌生长良好,所建立的方法可用于注射用利培酮微球的无菌检查.结论:注射用利培酮微球的无菌检查应包括表面无菌检查和内部无菌检查.二甲基亚砜(DMSO)可作为溶剂对微球进行溶解和破碎,从而进行内部无菌检查.

  5. Risperidone versus pimozide in Tourette's disorder : A comparative double-blind parallel-group study

    NARCIS (Netherlands)

    Bruggeman, R; van der Linden, C.; Buitelaar, JK; Gericke, GS; Hawkridge, SM; Temlett, JA

    2001-01-01

    Background: The treatment of Tourette's disorder with classical neuroleptics is limited by their side effects. Risperidone is a new efficacious antipsychotic with a low propensity for extrapyramidal side effects. To establish risperidone's therapeutic potential in Tourette's disorder, we studied the

  6. Doppler cooling a microsphere

    CERN Document Server

    Barker, P F

    2010-01-01

    Doppler cooling the center-of-mass motion of an optically levitated microsphere via the velocity dependent scattering force from narrow whispering gallery mode (WGM) resonances is described. Light that is red detuned from the WGM resonance can be used to damp the center-of-mass motion in a process analogous to the Doppler cooling of atoms. Leakage of photons out of the microsphere when the incident field is near resonant with the narrow WGM resonance acts to damp the motion of the sphere. The scattering force is not limited by saturation, but can be controlled by the incident power. Cooling times on the order of seconds are calculated for a 20 micron diameter silica microsphere trapped within optical tweezers, with a Doppler temperature limit in the microKelvin regime.

  7. B[e] Stars - Penetrating the Mystery of the Circumstellar Matter

    Science.gov (United States)

    Korčáková, D.; Miroshnichenko, A.; Shore, S. N.

    2017-04-01

    We present a brief overview of the published analyses of the long-term variability of FS CMa stars, a subgroup of the B[e] stars. We stress the importance of persistence for the study of the various physical processes in these objects and the essential role to be played by amateur-professional observational campaigns.

  8. A Case of Diabetic Ketoacidosis Associated with Risperidone Treatment

    Directory of Open Access Journals (Sweden)

    Zeynel Beyhan

    2008-12-01

    Full Text Available The association between schizophrenia and diabetes has been previously documented. Case reports have also demonstrated that initiation of atypical antipsychotic agents may induce or exacerbate diabetes mellitus. A 26-year-old man without a family history of diabetes mellitus presented with deep coma after 5 months of treatment with risperidone. He was diagnosed with diabetic ketoacidosis, was given insulin and saline infusion, and his antipsychotic agent was changed from risperidone to ziprasidone.Insulin therapy and oral agent was discontinued within two months of follow-up. The rapid onset of diabetes, and the disappearance of hyperglycemia after discontinuation of the drug suggested that risperidone had been a factor in his diabetic ketoacidosis. During three years of subsequent follow-up, testing revealed no evidence of elevated serum glucose levels or impaired glucose tolerance. In our opinion psychiatrists should routinely ask patients treated with antipsychotic agents such as risperidone for diabetic symptoms, weight loss, lethargy, polydipsia and/or polyuria, and monitor serum glucose levels. Although there is no consensus on the best way to switch from one antipsychotic drug to another, for those patients who develop diabetes during therapy with risperidone a change to ziprasidone treatment may maintain normal glucose levels.

  9. RP-HPLC estimation of risperidone in tablet dosage forms

    Directory of Open Access Journals (Sweden)

    Bladania S

    2008-01-01

    Full Text Available A simple, specific, accurate, and precise reverse phase liquid chromatographic method was developed and validated for the estimation of risperidone in tablet dosage forms. A Phenomenex Gemini C-18, 5 µm column having 250x4.6 mm i.d. in isocratic mode, with mobile phase containing methanol: acetonitrile: 50 mM potassium dihydrogen orthophosphate (80:10:10 v/v was used. The flow rate was 1.3 ml/min and effluents were monitored at 234 nm. Clozapine was used as an internal standard. The retention time of risperidone and clozapine were 2.5 min and 3.3 min, respectively. The method was validated for linearity, accuracy, precision, specificity, limit of quantification, limit of detection, robustness and stability. The limit of detection and limit of quantification for estimation of risperidone was found to be 500 ng/ml and 990 ng/ml, respectively. Recovery of risperidone was found to be in the range of 99.02-101.68%. Proposed method was successfully applied for the quantitative determination of risperidone in tablet formulations.

  10. Doped zinc oxide microspheres

    Science.gov (United States)

    Arnold, Jr., Wesley D.; Bond, Walter D.; Lauf, Robert J.

    1993-01-01

    A new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel.

  11. Polyvinyl pyridine microspheres

    Science.gov (United States)

    Rembaum, Alan (Inventor); Gupta, Amitava (Inventor); Volksen, Willi (Inventor)

    1980-01-01

    Microspheres are produced by cobalt gamma radiation initiated polymerization of a dilute aqueous vinyl pyridine solution. Addition of cross-linking agent provides higher surface area beads. Addition of monomers such as hydroxyethylmethacrylate acrylamide or methacrylamide increases hydrophilic properties and surface area of the beads. High surface area catalytic supports are formed in the presence of controlled pore glass substrate.

  12. PLGA Microspheres Incorporated Gelatin Scaffold: Microspheres Modulate Scaffold Properties

    OpenAIRE

    Indranil Banerjee; Debasish Mishra; Maiti, Tapas K.

    2009-01-01

    Freeze drying is one of the popular methods of fabrication for poly(lactide-co-glycolide) (PLGA) microspheres incorporated polymer scaffolds. However, the consequence of microspheres incorporation on physical and biological properties of scaffold has not been studied yet. In this study, attempt has been made to characterize the effect of PLGA microsphere incorporation on the physical properties of freeze-dried gelatin scaffold and its influence on cytocompatibility. Scaffolds loaded with va...

  13. Preparation of Bauxite Ceramic Microsphere

    Institute of Scientific and Technical Information of China (English)

    CHENG Xiaosu; LIU Pingan; LI Xiuyan; SHUI Anze; ZENG Lingke

    2007-01-01

    Ceramic microspheres were prepared by using Chinese bauxite as raw materials through the centrifugal spray drying method. The control technology of microsphere size, degree of sphericity was researched. The ceramic microspheres were sintered by a double sintering process. The microstructure and composition of ceramic microsphere were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray energy spectroscopy. The results show that the degree of sphericity of the ceramic microsphere was good and the particle size was 10-100 μm. The XRD analysis reveals that the main crystalline phase of the ceramic microsphere was α- Al2O3 and mullite (3Al2O3·2SiO2). The product can be used as reinforced material for composite material, especially for antiskid and hard wearing aluminum alloy coating.

  14. Unveiling the structure and kinematics of B[e] stars' disks from FEROS and CRIRES spectra

    CERN Document Server

    Muratore, M F; Kraus, M; Aret, A; Cidale, L S; Fernandes, M Borges; Oudmaijer, R D; Wheelwright, H E

    2012-01-01

    We are investigating the circumstellar material for a sample of B[e] stars using high spectral resolution data taken in the optical and near-infrared regions with ESO/FEROS and ESO/CRIRES spectrographs, respectively. B[e] stars are surrounded by dense disks of still unknown origin. While optical emission lines from [O I] and [Ca II] reflect the disk conditions close to the star (few stellar radii), the near-infrared data, especially the CO band emission, mirror the characteristics in the molecular part of the disk farther away from the star (several AU). Based on our high resolution spectroscopic data, we seek to derive the density and temperature structure of the disks, as well as their kinematics. This will allow us to obtain a better understanding of their structure, formation history and evolution. Here we present our preliminary results.

  15. Functional magnetic microspheres

    Science.gov (United States)

    Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Landel, Robert F. (Inventor)

    1981-01-01

    Functional magnetic particles are formed by dissolving a mucopolysaccharide such as chitosan in acidified aqueous solution containing a mixture of ferrous chloride and ferric chloride. As the pH of the solution is raised magnetite is formed in situ in the solution by raising the pH. The dissolved chitosan is a polyelectrolyte and forms micelles surrounding the granules at pH of 8-9. The chitosan precipitates on the granules to form microspheres containing the magnetic granules. On addition of the microspheres to waste aqueous streams containing dissolved ions, the hydroxyl and amine functionality of the chitosan forms chelates binding heavy metal cations such as lead, copper, and mercury and the chelates in turn bind anions such as nitrate, fluoride, phosphate and borate.

  16. Risk of extrapyramidal syndromes with haloperidol, risperidone, or olanzapine

    NARCIS (Netherlands)

    Schillevoort, I; de Boer, A; Herings, R M; Roos, R A; Jansen, P A; Leufkens, H G

    2001-01-01

    OBJECTIVE: To compare the risk of extrapyramidal syndrome (EPS) between risperidone, olanzapine, and haloperidol, taking into account patients' past antipsychotic drug use and past EPS. METHODS: Data were obtained from the PHARMO-database, containing filled prescriptions of 450,000

  17. Risperidone and Adaptive Behavior in Children with Autism

    Science.gov (United States)

    Williams, Susan K.; Scahill, Lawrence; Vitiello, Benedetto; Aman, Michael G.; Arnold, L. Eugene; McDougle, Christopher J.; McCracken, James T.; Tierney, Elaine; Ritz, Louise; Posey, David J.; Swiezy, Naomi B.; Hollway, Jill; Cronin, Pegeen; Ghuman, Jaswinder; Wheeler, Courtney; Cicchetti, Domenic; Sparrow, Sara

    2006-01-01

    Objective: To evaluate the impact of risperidone on adaptive behavior in children with autistic disorder who have serious behavior problems and to examine different methods of scoring the Vineland Adaptive Behavior Scales to measure change. Method: Forty-eight children (5 years to 16 years, 5 months) who showed behavioral improvement during acute…

  18. Risk of extrapyramidal syndromes with haloperidol, risperidone, or olanzapine

    NARCIS (Netherlands)

    Schillevoort, I; de Boer, A; Herings, R M; Roos, R A; Jansen, P A; Leufkens, H G

    2001-01-01

    OBJECTIVE: To compare the risk of extrapyramidal syndrome (EPS) between risperidone, olanzapine, and haloperidol, taking into account patients' past antipsychotic drug use and past EPS. METHODS: Data were obtained from the PHARMO-database, containing filled prescriptions of 450,000 community-dwellin

  19. Costs and efficacy ofolanzapine and risperidone in schizophrenia

    Directory of Open Access Journals (Sweden)

    Vittorio Mapelli

    2007-06-01

    Full Text Available Introduction: schizophrenia is a serious and long lasting psychiatric disease. The new “atypical” antipsychotic drugs, introduced in the 90s, have substantially improved the effectiveness of medical treatments, compared to previous neuroleptic drugs. Nowadays they tend to be used as first choice drugs. The ddd cost of atypicals may differ by 20% and health authorities may have an incentive to deliver the less costly drug, especially if they are generic. However the various drugs show differential effectiveness rates and a rational choice should consider both cost and effectiveness.
Objective: the purpose of this analysis is to review the existing evidence on cost-effectiveness studies of olanzapine and risperidone, the two most prescribed drugs in Italy. Six published studies were identified, but attention was focused on two articles that reported consistent and methodologically sound results.
Results: most reviewed studies are cost-minimization analyses, since effectiveness indicators show no significant statistical difference between the two drugs, and are inconclusive since the results depend on the evaluation setting. However one observational retrospective study showed a significant severity reduction over 12 months for patients treated with olanzapine (-2.46 on HoNOS scale; p<0.05, compared to a smaller non significant reduction of the risperidone group (-0.57. Despite the higher drug cost, the average total cost per reduced severity score was lower for olanzapine than for risperidone patients (€ 4,554 vs. € 10,897. The only medical and related health care costs for risperidone patients were higher than total costs for olanzapine patients. Another study comparing cohorts of patients with similar starting severity showed a significant severity reduction and global functioning increase over 12 months for olanzapine but no significant increase for risperidone patients (-0.35, p<0.01 on CGI scale; +3.66, p <0.05 on GAF scale

  20. Risperidone long-acting injectable monotherapy in the maintenance treatment of bipolar I disorder.

    Science.gov (United States)

    Quiroz, Jorge A; Yatham, Lakshmi N; Palumbo, Joseph M; Karcher, Keith; Kushner, Stuart; Kusumakar, Vivek

    2010-07-15

    Treatment adherence is a significant problem in patients with bipolar disorder. This study was designed to determine the efficacy of risperidone long-acting injectable (LAI) in the maintenance treatment of bipolar I disorder. Eligible patients with current or recent manic or mixed episodes (n = 559, aged 18-65 years) were treated with open-label oral risperidone for 3 weeks (period II) and open-label risperidone LAI for 26 weeks (n = 501; period III). Patients who maintained response (n = 303) were randomly allocated 1:1 to placebo injections (n = 149) or to continue risperidone LAI (n = 154) for up to 24 months (period IV). Most (77%) patients on risperidone LAI received a dose of 25 mg every 2 weeks during period IV. Time to recurrence for any mood episode (primary outcome variable) was significantly longer in the risperidone LAI group versus placebo (p or = 7% (compared with the period's baseline) occurred in 15% of patients in period III; in 12% of patients on risperidone LAI and 3% of patients on placebo in period IV. Risperidone LAI monotherapy significantly delayed the time to recurrence of mood episodes, versus placebo, in this controlled, randomized study in patients with bipolar I disorder. Risperidone LAI was tolerable and no new safety concerns emerged compared with previous studies of risperidone LAI. Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  1. Ringing phenomenon in silica microspheres

    Institute of Scientific and Technical Information of China (English)

    Chunhua Dong; Changling Zou; Jinming Cui; Yong Yang; Zhengfu Han; Guangcan Guo

    2009-01-01

    Whispering gallery modes in silica microspheres are excited by a tunable continuous-wave laser through the fiber taper. Ringing phenomenon can be observed with high frequency sweeping speed. The thermal nonlinearity in the microsphere can enhance this phenomenon. Our measurement results agree very well with the theoretical predictions by the dynamic equation.

  2. Risperidone-induced enuresis in a 12-year-old child

    Directory of Open Access Journals (Sweden)

    Reetika Dikshit

    2017-01-01

    Full Text Available Risperidone has been documented to be effective in the management of behavior problems, aggression, and conduct disorder in children. While metabolic side effects like weight gain and obesity have been attributed to Risperidone use in children, side effects of the drug related to the urinary bladder are rare. We present a case of Risperidone-induced enuresis in a 12-year-old boy with conduct disorder that resolved completely after stopping the medication.

  3. Risperidone-induced Enuresis in a 12-year-old Child

    Science.gov (United States)

    Dikshit, Reetika; Karia, Sagar; De Sousa, Avinash

    2017-01-01

    Risperidone has been documented to be effective in the management of behavior problems, aggression, and conduct disorder in children. While metabolic side effects like weight gain and obesity have been attributed to Risperidone use in children, side effects of the drug related to the urinary bladder are rare. We present a case of Risperidone-induced enuresis in a 12-year-old boy with conduct disorder that resolved completely after stopping the medication. PMID:28149096

  4. Using Glycopyrrolate as an alternative option in case of Risperidone induced sialorrhoea

    Directory of Open Access Journals (Sweden)

    Dr. Hemanta Dutta

    2015-03-01

    Full Text Available Drug induced hypersalivation has been playing an unique factor in terms of noncompliance of antipsychotics. Hypersalivation has been described commonly with clozapine. Although Risperidone is also seen to be notorious to be causing hypersalivation. Use of Glycopyrrolate in Risperidone induced hypersalivation has not been covered though reported studies till yet. Here we are depicting the use of Glycopyrrolate as an alternative treatment option for hypersalivation induced by Risperidone.

  5. Preparation of Functional Polymeric Microspheres

    Institute of Scientific and Technical Information of China (English)

    Changchun Wang; Yonghui Deng; Wuli Yang; Shoukuang Fu

    2005-01-01

    @@ 1Introduction Because of the wide applications in the area of biomedical and biotechnological fields, a great efforts have been done to fabricate different kinds of microspheres with tailored structural and surface properties over the last decade[1]. Among them, stimuli responsive microspheres are microspheres that show ability to change their physical-chemical properties and colloidal properties in response to environmental stimuli such as changes of temperature, pH, chemicals, light, electrical field, magnetic field or mechanic stress, etc. These microspheres have been under intensive study for their high potential applications in biomedical and biotechnological fields such as controlled drug delivery[2], biosensor[3], chemical isolation[4], cell culture substrates[5], enzyme immobilization[6], bioelectrocatalysis[7], and magnetically controlled electrochemical reaction[8]. However,most of the reported stimuli responsive microspheres only show response to one specific stimulus. Up to now,to the best of our knowledge, only a few works have been directed to the fabrication of microspheres which show response to more than one stimulus[9]. In this paper, a system synthesis method for stimuli responsive microspheres with more useful properties was reported, and the simple application in biomedical area have been mentioned.

  6. Multiple dose pharmacokinetics of risperidone and 9-hydroxyrisperidone in Chinese female patients with schizophrenia

    Institute of Scientific and Technical Information of China (English)

    Zhi-ling ZHOU; Qiu-xiong LIN; Chuan-yue WANG; Wen-biao LI; Shu-guang LIN; Huan-de LI; Xin LI; Huai-yan PENG; Xi-yong YU; Ming YANG; Feng-li SU; Feng WANG; Rong-hua ZHU; Chun-yu DENG

    2006-01-01

    Aim: To study the multiple dose clinical pharmacokinetics of risperidone and its main active metabolite, 9-hydroxyrisperidone, in Chinese female patients with schizophrenia. Methods: The subjects were 23 Chinese female inpatients aged 18-65 years who met the CCMD-Ⅲ (third revision of the Chinese Criteria of Mental Disorders) criteria for schizophrenia. Subjects were tested after 17 d of treatment with 2 mg risperidone twice daily. Plasma concentrations of risperidone and 9-hydroxy-risperidone were assayed by using validated high performance liquid chromatography-mass spectrometry (HPLC-MS) methods. Results: Risperidone was rapidly absorbed (Tmax was 1.6 h) and its Tin in plasma was short (3.2 h).9-hydroxy-risperidone was quickly metabolized from the parent drug with a mean Tmax of 2.5 h. It had a long half-life of 24.7 h. The Cssav of risperidone and 9-hydroxyrisperidone were 36.9±33.1 and 110.6±30.5 μg·h·L-1, respectively, and the AUCss0-12 were 443.2±397.4 and 1327.2±402.3 μg·h·L-1, respectively. CL/F and V/F of risperidone were 8.7±6.2 L/h and 34.1±24.3 L, respectively. Interindividual variations for pharmacokinetic parameters were quite large for risperidone. All 23 subjects experienced high prolactin levels when treated with risperidone. However there was no correlation between prolactin level and the concentration of risperidone, 9-hydroxy-risperidone, or the active moiety. Conclusion: Risperidone showed large interindividual variations in pharmacokinetics. Administration of risperidone resulted in high serum prolactin levels. The results indicate that systemic exposure to risperidone and 9-hydroxy-risperidone in female Chinese schizophrenic patients is higher relative to published data for white Caucasian patients. Larger studies regarding the PK/PD relationship may be required to develop a reasonable clinical dosage regimen for Chinese female patients.

  7. Mucoadhesive Microsphere - Review

    Directory of Open Access Journals (Sweden)

    Ratnaparkhi M P

    2014-06-01

    Full Text Available Several approaches have been immerged to prolong the residence time of the dosage forms at the absorption site and one of them is the development of oral controlled release mucoadhesive system. Mucoadhesive drug delivery systems are used to enhance drug absorption in a site-specific manner. Bioadhesion has been defined as the attachment of synthetic or biological macromolecules to a biological tissue. The biological surface can be epithelial tissue or the mucous coat on the surface of a tissue. If adhesive attachment is to a mucous coat, the phenomenon is referred to as mucoadhesion. Mucus is a thin blanket covering all epithelia that are in contact with the external environment in the gastrointestinal, respiratory, and urogenital tracts. This approach involves the use of mucoadhesive polymers, which can adhere to the epithelial surface in the stomach. Carrier technology offers an intelligent approach for drug delivery by coupling the drug to a carrier particle such as microspheres, nanospheres, liposomes, nanoparticles, etc., which modulates the release and absorption of the drug. Microspheres constitute an important part of these particulate drug delivery systems by virtue of their small size and efficient carrier capacity.

  8. VLT/MUSE discovers a jet from the evolved B[e] star MWC 137

    CERN Document Server

    Mehner, A; Groh, J H; Oudmaijer, R D; Baade, D; Rivinius, T; Selman, F; Boffin, H M J; Martayan, C

    2016-01-01

    Not all stars exhibiting the optical spectral characteristics of B[e] stars share the same evolutionary stage. The Galactic B[e] star MWC 137 is a prime example of an object with uncertain classification, with previous work suggesting pre- and post-main sequence classification. Our goal is to settle this debate and provide reliable evolutionary classification. Integral field spectrograph observations with VLT MUSE of the cluster SH 2-266 are used to analyze the nature of MWC 137. A collimated outflow is discovered that is geometrically centered on MWC 137. The central position of MWC 137 in the cluster SH 2-266 within the larger nebula suggests strongly that it is a member of this cluster and that it is both at the origin of the nebula and the newly discovered jet. Comparison of the color-magnitude diagram of the brightest cluster stars with stellar evolutionary models results in a distance of about 5.2$\\pm$1.4 kpc. We estimate that the cluster is at least 3 Myr old. The jet extends over 66" (1.7 pc) projecte...

  9. ALMA observations of the supergiant B[e] star Wd1-9

    Science.gov (United States)

    Fenech, D. M.; Clark, J. S.; Prinja, R. K.; Morford, J. C.; Dougherty, S.; Blomme, R.

    2017-01-01

    Mass-loss in massive stars plays a critical role in their evolution, although the precise mechanism(s) responsible - radiatively driven winds, impulsive ejection and/or binary interaction - remain uncertain. In this Letter, we present Atacama Large Millimetre/Submillimeter Array line and continuum observations of the supergiant B[e] star Wd1-9, a massive post-main-sequence object located within the starburst cluster Westerlund 1 (Wd1). We find it to be one of the brightest stellar point sources in the sky at millimetre wavelengths, with (serendipitously identified) emission in the H41α radio recombination line. We attribute these properties to a low velocity (˜100 km s-1 ) ionized wind, with an extreme mass-loss rate ≳6.4 × 10-5(d/5 kpc)1.5 M⊙yr- 1. External to this is an extended aspherical ejection nebula indicative of a prior phase of significant mass-loss. Taken together, the millimetre properties of Wd1-9 show a remarkable similarity to those of the highly luminous stellar source MWC349A. We conclude that these objects are interacting binaries evolving away from the main sequence and undergoing rapid case-A mass transfer. As such they - and by extension the wider class of supergiant B[e] stars - may provide a unique window into the physics of a process that shapes the life-cycle of ˜70 per cent of massive stars found in binary systems.

  10. Spectroscopic survey of emission-line stars. I. B[e] stars

    CERN Document Server

    Aret, Anna; Šlechta, Miroslav

    2015-01-01

    Emission-line stars are typically surrounded by dense circumstellar material, often in form of rings or disc-like structures. Line emission from forbidden transitions trace a diversity of density and temperature regimes. Of particular interest are the forbidden lines of [O I] {\\lambda}{\\lambda}6300, 6364 and [Ca II] {\\lambda}{\\lambda}7291, 7324. They arise in complementary, high-density environments, such as the inner-disc regions around B[e] supergiants. To study physical conditions traced by these lines and to investigate how common they are, we initiated a survey of emission-line stars. Here, we focus on a sample of nine B[e] stars in different evolutionary phases. Emission of the [O I] lines is one of the characteristics of B[e] stars. We find that four of the objects display [Ca II] line emission: for the B[e] supergiants V1478 Cyg and 3 Pup the kinematics obtained from the [O I] and [Ca II] line profiles agrees with a Keplerian rotating disc scenario; the forbidden lines of the compact planetary nebula ...

  11. Neuroleptic malignant syndrome due to risperidone misdiagnosed as status epilepticus

    Directory of Open Access Journals (Sweden)

    Ali Ertug Arslankoylu

    2011-06-01

    Full Text Available Neuroleptic malignant syndrome (NMS is a rare but potentially fatal disease characterized by fever, muscle rigidity, delirium and autonomic instability. Here we report a child, with NMS due to the risperidone misdiagnosed as status epilepticus. Nine year old boy, who had been under high dose risperidone treatment for 8 weeks, admitted to the emergency room because of the contractions (evaluated as status epilepticus persisting for 7 hours. Since there was neuroleptic treatment in the past medical history and, unconsciousness, muscular rigidity, diaphoresis, hypertermi and, hypotension in physical examination, leucocytosis and elevated creatininphosphokinase levels in laboratory tests, the patient was evaluated as NMS and discharged without any complications. We reported this case to point out that; NMS may be misdiagnosed as status epilepticus in children when EEG monitoring is unavailable. When a child admitted to the emergency room because of suspicious convulsion neuroleptic drug use must surely be asked.

  12. A comparison between augmentation with olanzapine and increased risperidone dose in acute schizophrenia patients showing early non-response to risperidone.

    Science.gov (United States)

    Hatta, Kotaro; Otachi, Taro; Sudo, Yasuhiko; Kuga, Hironori; Takebayashi, Hiroshi; Hayashi, Hideaki; Ishii, Ryusuke; Kasuya, Masataka; Hayakawa, Tatsuro; Morikawa, Fumiyoshi; Hata, Kazuya; Nakamura, Mitsuru; Usui, Chie; Nakamura, Hiroyuki; Hirata, Toyoaki; Sawa, Yutaka

    2012-07-30

    We examined whether augmentation with olanzapine would be superior to increased risperidone dose among acute schizophrenia patients showing early non-response to risperidone. We performed a rater-blinded, randomized controlled trial at psychiatric emergency sites. Eligible patients were newly admitted patients with acute schizophrenia. Early response was defined as Clinical Global Impressions-Improvement Scale score ≤3 following 2 weeks of treatment. Early non-responders were allocated to receive either augmentation with olanzapine (RIS+OLZ group) or increased risperidone dose (RIS+RIS group). The 78 patients who completed 2 weeks of treatment were divided into 52 early responders to risperidone and 26 early non-responders to risperidone (RIS+OLZ group, n=13; RIS+RIS group, n=13). No difference in the achievement of ≥50% improvement in Positive and Negative Syndrome Scale total score was observed between RIS+OLZ and RIS+RIS groups. Although time to treatment discontinuation for any cause was significantly shorter in the RIS+RIS group (6.8 weeks [95% confidence interval, 5.2-8.4]) than in early responders to risperidone (8.6 weeks [7.9-9.3]; P=0.018), there was no significant difference between the RIS+OLZ group (7.9 weeks [6.3-9.5]) and early responders to risperidone. Secondary outcomes justify the inclusion of augmentation arms in additional, larger studies comparing strategies for early non-responders.

  13. Glass microsphere lubrication

    Science.gov (United States)

    Geiger, Michelle; Goode, Henry; Ohanlon, Sean; Pieloch, Stuart; Sorrells, Cindy; Willette, Chris

    1991-01-01

    The harsh lunar environment eliminated the consideration of most lubricants used on earth. Considering that the majority of the surface of the moon consists of sand, the elements that make up this mixture were analyzed. According to previous space missions, a large portion of the moon's surface is made up of fine grained crystalline rock, about 0.02 to 0.05 mm in size. These fine grained particles can be divided into four groups: lunar rock fragments, glasses, agglutinates (rock particles, crystals, or glasses), and fragments of meteorite material (rare). Analysis of the soil obtained from the missions has given chemical compositions of its materials. It is about 53 to 63 percent oxygen, 16 to 22 percent silicon, 10 to 16 percent sulfur, 5 to 9 percent aluminum, and has lesser amounts of magnesium, carbon, and sodium. To be self-supporting, the lubricant must utilize one or more of the above elements. Considering that the element must be easy to extract and readily manipulated, silicon or glass was the most logical choice. Being a ceramic, glass has a high strength and excellent resistance to temperature. The glass would also not contaminate the environment as it comes directly from it. If sand entered a bearing lubricated with grease, the lubricant would eventually fail and the shaft would bind, causing damage to the system. In a bearing lubricated with a solid glass lubricant, sand would be ground up and have little effect on the system. The next issue was what shape to form the glass in. Solid glass spheres was the only logical choice. The strength of the glass and its endurance would be optimal in this form. To behave as an effective lubricant, the diameter of the spheres would have to be very small, on the order of hundreds of microns or less. This would allow smaller clearances between the bearing and the shaft, and less material would be needed. The production of glass microspheres was divided into two parts, production and sorting. Production includes the

  14. Prolactin release in children treated with risperidone - Impact and role of CYP2D6 metabolism

    NARCIS (Netherlands)

    Troost, Pieter W.; Lahuis, Bertine E.; Hermans, Mirjam H.; Buitelaar, Jan K.; van Engeland, Herman; Scahill, Lawrence; Minderaa, Ruud B.; Hoekstra, Pieter J.

    2007-01-01

    Objective: Little is known about the role of CYP2136 polymorphism in risperidone-induced prolactin release in children. Method: Twenty-five children (aged 5-15 years) with pervasive developmental disorders were genotyped for CYP2D6 polymorphisms. Serum prolactin, risperidone, and 9-hydroxyrisperidon

  15. Formulation, in vitro and in vivo evaluation of transdermal patches containing risperidone.

    Science.gov (United States)

    Aggarwal, Geeta; Dhawan, Sanju; Hari Kumar, S L

    2013-01-01

    The efficacy of oral risperidone treatment in prevention of schizophrenia is well known. However, oral side effects and patient compliance is always a problem for schizophrenics. In this study, risperidone was formulated into matrix transdermal patches to overcome these problems. The formulation factors for such patches, including eudragit RL 100 and eudragit RS 100 as matrix forming polymers, olive oil, groundnut oil and jojoba oil in different concentrations as enhancers and amount of drug loaded were investigated. The transdermal patches containing risperidone were prepared by solvent casting method and characterized for physicochemical and in vitro permeation studies through excised rat skin. Among the tested preparations, formulations with 20% risperidone, 3:2 ERL 100 and ERS 100 as polymers, mixture of olive oil and jojoba oil as enhancer, exhibited greatest cumulative amount of drug permeated (1.87 ± 0.09 mg/cm(2)) in 72 h, so batch ROJ was concluded as optimized formulation and assessed for pharmacokinetic, pharmacodynamic and skin irritation potential. The pharmacokinetic characteristics of the optimized risperidone patch were determined using rabbits, while orally administered risperidone in solution was used for comparison. The calculated relative bioavailability of risperidone transdermal patch was 115.20% with prolonged release of drug. Neuroleptic efficacy of transdermal formulation was assessed by rota-rod and grip test in comparison with control and marketed oral formulations with no skin irritation. This suggests the transdermal application of risperidone holds promise for improved bioavailability and better management of schizophrenia in long-term basis.

  16. Clinical utility of the risperidone formulations in the management of schizophrenia

    Directory of Open Access Journals (Sweden)

    Madaan V

    2011-10-01

    Full Text Available Vishal Madaan1, Durga P Bestha2, Venkata Kolli2, Saurabh Jauhari2, Roger C Burket1 1University of Virginia Health System, Charlottesville, VA, USA; 2Creighton University Medical Center, Omaha, NE, USA Abstract: Risperidone is one of the early second-generation antipsychotics that came into the limelight in the early 1990s. Both the oral and long-acting injectable formulations have been subject to numerous studies to assess their safety, efficacy, and tolerability. Risperidone is currently one of the most widely prescribed antipsychotic medications, used for both acute and long-term maintenance in schizophrenia. Risperidone has better efficacy in the treatment of psychotic symptoms than placebo and possibly many first-generation antipsychotics. Risperidone fares better than placebo and first-generation antipsychotics in the treatment of negative symptoms. Risperidone's long acting injectable preparation has been well tolerated and is often useful in patients with medication nonadherence. Risperidone has a higher risk of hyperprolactinemia comparable to first-generation antipsychotics (FGAs but fares better than many second-generation antipsychotics with regards to metabolic side effects. In this article, we briefly review the recent literature exploring the role of risperidone formulations in schizophrenia, discuss clinical usage, and highlight the controversies and challenges associated with its use. Keywords: risperidone, schizophrenia, formulation, antipsychotic, side effects

  17. A randomized open-label comparison of the impact of olanzapine versus risperidone on sexual functioning

    NARCIS (Netherlands)

    Knegtering, H; Boks, M; Blijd, C; Castelein, S; Van den Bosch, RJ; Wiersma, D

    2006-01-01

    The objective of this study was to compare sexual functioning in patients treated with olanzapine or risperidone. This open-label trial included 46 patients randomized to olanzapine (5-15mg/d) or risperidone (1-6mg/d) for 6 weeks. We used sexual dysfunction was assessed by a semistructured interview

  18. Risperidone in the management of agitation and aggression associated with psychiatric disorders.

    NARCIS (Netherlands)

    Deyn, P.P. de; Buitelaar, J.K.

    2006-01-01

    OBJECTIVE: This review provides an overview of the prevalence and treatment of agitation and aggression, and focuses on the use of risperidone to treat these symptoms in patients from different age groups. METHODS: MEDLINE and EMBASE databases were used to identify controlled studies of risperidone

  19. The Jet from MWC 137 Points at a Supergiant B[e] Star in a Binary

    Science.gov (United States)

    Mehner, A.; de Wit, W. J.; Groh, J. H.; Oudmaijer, R. D.; Baade, D.; Rivinius, Th.; Selman, F.; Boffin, H. M. J.; Martayan, C.

    2017-02-01

    The Galactic B[e] star MWC 137 is a prime example of an object with an uncertain evolutionary classification. Previous work has suggested that is either a pre- or a post-main sequence object. Integral field spectrograph observations with the Very Large Telescope Multi Unit Spectroscopic Explorer (VLT MUSE) of the host cluster SH 2-266 are used to provide a reliable evolutionary classification. The MUSE data also allowed the discovery of a large collimated outflow, geometrically centered on MWC 137. A color-magnitude diagram analysis of the cluster promotes strongly a post-main sequence stage for MWC 137, while the existence of a jet implies the presence of an accretion disk. A SWIFT X-ray source, which may be associated with MWC 137, hints at the possibility of a neutron star companion.

  20. The supergiant B[e] star LHA 115-S 18 - binary and/or luminous blue variable?

    CERN Document Server

    Clark, J S; Coe, M J; Dorda, R; Haberl, F; Lamb, J B; Negueruela, I; Udalski, A

    2013-01-01

    The mechanism by which supergiant (sg)B[e] stars support cool, dense dusty discs/tori and their physical relationship with other evolved, massive stars such as luminous blue variables is uncertain. In order to investigate both issues we have analysed the long term behaviour of the canonical sgB[e] star LHA 115-S 18. We employed the OGLE II-IV lightcurve to search for (a-)periodic variability and supplemented these data with new and historic spectroscopy. In contrast to historical expectations for sgB[e] stars, S18 is both photometrically and spectroscopically highly variable. The lightcurve is characterised by rapid aperiodic `flaring' throughout the 16 years of observations. Changes in the high excitation emission line component of the spectrum imply evolution in the stellar temperature - as expected for luminous blue variables - although somewhat surprisingly, spectroscopic and photometric variability appears not to be correlated. Characterised by emission in low excitation metallic species, the cool circum...

  1. The VLT-FLAMES Tarantula Survey. XV. VFTS\\,822: a candidate Herbig B[e] star at low metallicity

    CERN Document Server

    Kalari, V M; Dufton, P L; Evans, C J; Dunstall, P R; Sana, H; Clark, J S; Ellerbroek, L; de Koter, A; Lennon, D J; Taylor, W D

    2014-01-01

    We report the discovery of the B[e] star VFTS 822 in the 30 Doradus star-forming region of the Large Magellanic Cloud, classified by optical spectroscopy from the VLT-FLAMES Tarantula Survey and complementary infrared photometry. VFTS 822 is a relatively low-luminosity (log $L$ = 4.04 $\\pm$ 0.25 $L_{\\odot}$) B8[e] star. In this Letter, we evaluate the evolutionary status of VFTS 822 and discuss its candidacy as a Herbig B[e] star. If the object is indeed in the pre-main sequence phase, it would present an exciting opportunity to measure mass accretion rates at low metallicity spectroscopically, to understand the effect of metallicity on accretion rates.

  2. Evidence of the evolved nature of the B[e] star MWC 137

    Energy Technology Data Exchange (ETDEWEB)

    Muratore, M. F.; Arias, M. L.; Cidale, L. [Departamento de Espectroscopía Estelar, Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, and Instituto de Astrofísica de La Plata, CCT La Plata, CONICET-UNLP, Paseo del Bosque S/N, B1900FWA, La Plata (Argentina); Kraus, M.; Oksala, M. E. [Astronomický ústav, Akademie věd České Republiky, Fričova 298, 251 65 Ondřejov (Czech Republic); Fernandes, M. Borges [Observatório Nacional, Rua General José Cristino 77, 20921-400 São Cristovão, Rio de Janeiro (Brazil); Liermann, A., E-mail: fmuratore@carina.fcaglp.unlp.edu.ar [Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany)

    2015-01-01

    The evolutionary phase of B[e] stars is difficult to establish due to the uncertainties in their fundamental parameters. For instance, possible classifications for the Galactic B[e] star MWC 137 include pre-main-sequence and post-main-sequence phases, with a large range in luminosity. Our goal is to clarify the evolutionary stage of this peculiar object, and to study the CO molecular component of its circumstellar medium. To this purpose, we modeled the CO molecular bands using high-resolution K-band spectra. We find that MWC 137 is surrounded by a detached cool (T=1900±100 K) and dense (N=(3±1)×10{sup 21} cm{sup −2}) ring of CO gas orbiting the star with a rotational velocity, projected to the line of sight, of 84 ± 2 km s{sup −1}. We also find that the molecular gas is enriched in the isotope {sup 13}C, excluding the classification of the star as a Herbig Be. The observed isotopic abundance ratio ({sup 12}C/{sup 13}C = 25 ± 2) derived from our modeling is compatible with a proto-planetary nebula, main-sequence, or supergiant evolutionary phase. However, based on some observable characteristics of MWC 137, we propose that the supergiant scenario seems to be the most plausible. Hence, we suggest that MWC 137 could be in an extremely short-lived phase, evolving from a B[e] supergiant to a blue supergiant with a bipolar ring nebula.

  3. Microspheres and their methods of preparation

    Science.gov (United States)

    Bose, Anima B; Yang, Junbing

    2015-03-24

    Carbon microspheres are doped with boron to enhance the electrical and physical properties of the microspheres. The boron-doped carbon microspheres are formed by a CVD process in which a catalyst, carbon source and boron source are evaporated, heated and deposited onto an inert substrate.

  4. Floating microspheres: a review

    Directory of Open Access Journals (Sweden)

    Jagtap Yogesh Mukund

    2012-03-01

    Full Text Available Gastric emptying is a complex process, one that is highly variable and that makes in vivo performance of drug delivery systems uncertain. A controlled drug delivery system with prolonged residence time in the stomach can be of great practical importance for drugs with an absorption window in the upper small intestine. The main limitations are attributed to the inter- and intra-subject variability of gastro-intestinal (GI transit time and to the non-uniformity of drug absorption throughout the alimentary canal. Floating or hydrodynamically controlled drug delivery systems are useful in such applications. Various gastroretentive dosage forms are available, including tablets, capsules, pills, laminated films, floating microspheres, granules and powders. Floating microspheres have been gaining attention due to the uniform distribution of these multiple-unit dosage forms in the stomach, which results in more reproducible drug absorption and reduced risk of local irritation. Such systems have more advantages over the single-unit dosage forms. The present review briefly addresses the physiology of the gastric emptying process with respect to floating drug delivery systems. The purpose of this review is to bring together the recent literature with respect to the method of preparation, and various parameters affecting the performance and characterization of floating microspheres.O esvaziamento gástrico é um processo complexo, com elevada variabilidade e responsável pela incerteza do desempenho dos medicamentos in vivo. Dessa forma, os sistemas de liberação modificada de fármacos, com tempo de residência prolongado no estômago, em especial, considerando aqueles fármacos com janela de absorção na porção superior do intestino delgado, apresentam fundamental importância. As principais limitações relativas à absorção do fármaco são, no geral, atribuídas à variabilidade inter e intra-paciente do tempo de trânsito gastro-intestinal (GI e

  5. Advances in Microsphere Insulation Systems

    Science.gov (United States)

    Allen, M. S.; Baumgartner, R. G.; Fesmire, J. E.; Augustynowicz, S. D.

    2004-06-01

    Microsphere insulation, typically consisting of hollow glass bubbles, combines in a single material the desirable properties that other insulations only have individually. The material has high crush strength, low density, is noncombustible, and performs well in soft vacuum. Microspheres provide robust, low-maintenance insulation systems for cryogenic transfer lines and dewars. They also do not suffer from compaction problems typical of perlite that result in the necessity to reinsulate dewars because of degraded thermal performance and potential damage to its support system. Since microspheres are load bearing, autonomous insulation panels enveloped with lightweight vacuum-barrier materials can be created. Comprehensive testing performed at the Cryogenics Test Laboratory located at the NASA Kennedy Space Center demonstrated competitive thermal performance with other bulk materials. Test conditions were representative of actual-use conditions and included cold vacuum pressure ranging from high vacuum to no vacuum and compression loads from 0 to 20 psi. While microspheres have been recognized as a legitimate insulation material for decades, actual implementation has not been pursued. Innovative microsphere insulation system configurations and applications are evaluated.

  6. Optical trapping of coated microspheres.

    Science.gov (United States)

    Bormuth, Volker; Jannasch, Anita; Ander, Marcel; van Kats, Carlos M; van Blaaderen, Alfons; Howard, Jonathon; Schäffer, Erik

    2008-09-01

    In an optical trap, micron-sized dielectric particles are held by a tightly focused laser beam. The optical force on the particle is composed of an attractive gradient force and a destabilizing scattering force. We hypothesized that using anti-reflection-coated microspheres would reduce scattering and lead to stronger trapping. We found that homogeneous silica and polystyrene microspheres had a sharp maximum trap stiffness at a diameter of around 800 nm--the trapping laser wavelength in water--and that a silica coating on a polystyrene microsphere was a substantial improvement for larger diameters. In addition, we noticed that homogeneous spheres of a correct size demonstrated anti-reflective properties. Our results quantitatively agreed with Mie scattering calculations and serve as a proof of principle. We used a DNA stretching experiment to confirm the large linear range in detection and force of the coated microspheres and performed a high-force motor protein assay. These measurements show that the surfaces of the coated microspheres are compatible with biophysical assays.

  7. Combination treatment of tamoxifen with risperidone in breast cancer.

    Directory of Open Access Journals (Sweden)

    Wei-Lan Yeh

    Full Text Available Tamoxifen has long been used and still is the most commonly used endocrine therapy for treatment of both early and advanced estrogen receptor-positive breast cancer in pre- and post-menopause women. Tamoxifen exerts its cytotoxic effect primarily through cytostasis which is associated with the accumulation of cells in the G0/G1 phase of the cell cycle. Apoptotic activity can also be exerted by tamoxifen which involves cleavage of caspase 9, caspase 7, caspase 3, and poly-ADP-ribose polymerase (PARP. Down-regulation of anti-apoptotic proteins Bcl-2 and Bcl-xL and up-regulation of pro-apoptotic proteins Bax and Bak have also been observed. In addition, stress response protein of GRP 94 and GRP 78 have also been induced by tamoxifen in our study. However, side effects occur during tamoxifen treatment in breast cancer patients. Researching into combination regimen of tamoxifen and drug(s that relieves tamoxifen-induced hot flushes is important, because drug interactions may decrease tamoxifen efficacy. Risperidone has been shown to be effective in reducing or eliminating hot flushes on women with hormonal variations. In this present study, we demonstrated that combination of tamoxifen with risperidone did not interfered tamoxifen-induced cytotoxic effects in both in vitro and in vivo models, while fluoxetine abrogated the effects of tamoxifen. This is the first paper suggesting the possibility of combination treatment of tamoxifen with risperidone in breast cancer patients, providing a conceivable resolution of tamoxifen-induced side effects without interfering the efficacy of tamoxifen against breast cancer.

  8. Effectiveness of injectable risperidone long-acting therapy for schizophrenia: data from the US, Spain, Australia, and Belgium

    Directory of Open Access Journals (Sweden)

    Macfadden Wayne

    2011-04-01

    Full Text Available Abstract Background Because wide variations in mental health care utilization exist throughout the world, determining long-term effectiveness of psychotropic medications in a real-world setting would be beneficial to physicians and patients. The purpose of this analysis was to describe the effectiveness of injectable risperidone long-acting therapy (RLAT for schizophrenia across countries. Methods This was a pragmatic analysis of data from two prospective observational studies conducted in the US (Schizophrenia Outcomes Utilization Relapse and Clinical Evaluation [SOURCE]; ClinicalTrials.gov registration number for the SOURCE study: NCT00246194 and Spain, Australia, and Belgium (electronic Schizophrenia Treatment Adherence Registry [eSTAR]. Two separate analyses were performed to assess clinical improvement during the study and estimate psychiatric hospitalization rates before and after RLAT initiation. Clinical improvement was evaluated using the Clinical Global Impressions-Severity (CGI-S and Global Assessment of Functioning (GAF scales, and change from baseline was evaluated using paired t tests. Psychiatric hospitalization rates were analyzed using incidence densities, and the bootstrap resampling method was used to examine differences between the pre-baseline and post-baseline periods. Results The initial sample comprised 3,069 patients (US, n = 532; Spain, n = 1,345; Australia, n = 784; and Belgium, n = 408. In all, 24 months of study participation, completed by 39.3% (n = 209, 62.7% (n = 843, 45.8% (n = 359, and 64.2% (n = 262 of patients from the US, Spain, Australia, and Belgium, respectively, were included in the clinical analysis. Improvements compared with baseline were observed on both clinical assessments across countries (P P P Conclusions RLAT in patients with schizophrenia was associated with improvements in clinical and functional outcomes and decreased hospitalization rates in the US, Spain, Australia, and Belgium, despite

  9. Polarization Dependent Whispering Gallery Modes in Microspheres

    Science.gov (United States)

    Adamovsky, Grigory (Inventor); Wrbanek, Susan Y. (Inventor)

    2016-01-01

    A tunable resonant system is provided and includes a microsphere that receives an incident portion of a light beam generated via a light source, the light beam having a fundamental mode, a waveguide medium that transmits the light beam from the light source to the microsphere, and a polarizer disposed in a path of the waveguide between the light source and the microsphere. The incident portion of the light beam creates a fundamental resonance inside the microsphere. A change in a normalized frequency of the wavelength creates a secondary mode in the waveguide and the secondary mode creates a secondary resonance inside the microsphere.

  10. Porous microsphere and its applications

    Directory of Open Access Journals (Sweden)

    Cai Y

    2013-03-01

    Full Text Available Yunpeng Cai,1,2* Yinghui Chen,3* Xiaoyun Hong,2 Zhenguo Liu,1 Weien Yuan2 1Department of Neurology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, 2School of Pharmacy, Shanghai JiaoTong University, 3Department of Neurology Jinshan Hospital, Fudan University, Shanghai, People's Republic of China *These authors contributed equally to this workAbstract: Porous microspheres have drawn great attention in the last two decades for their potential applications in many fields, such as carriers for drugs, absorption and desorption of substances, pulmonary drug delivery, and tissue regeneration. The application of porous microspheres has become a feasible way to address existing problems. In this essay, we give a brief introduction of the porous microsphere, its characteristics, preparation methods, applications, and a brief summary of existing problems and research tendencies.Keywords: pore, porosity, porogen, suspension polymerization, seed swelling, pulmonary drug delivery, tissue regeneration

  11. Evidence of the Evolved Nature of the B[e] Star MWC 137

    Science.gov (United States)

    Muratore, M. F.; Kraus, M.; Oksala, M. E.; Arias, M. L.; Cidale, L.; Borges Fernandes, M.; Liermann, A.

    2015-01-01

    The evolutionary phase of B[e] stars is difficult to establish due to the uncertainties in their fundamental parameters. For instance, possible classifications for the Galactic B[e] star MWC 137 include pre-main-sequence and post-main-sequence phases, with a large range in luminosity. Our goal is to clarify the evolutionary stage of this peculiar object, and to study the CO molecular component of its circumstellar medium. To this purpose, we modeled the CO molecular bands using high-resolution K-band spectra. We find that MWC 137 is surrounded by a detached cool (T=1900+/- 100 K) and dense (N=(3+/- 1)× {{10}21} {{cm}-2}) ring of CO gas orbiting the star with a rotational velocity, projected to the line of sight, of 84 ± 2 km s-1. We also find that the molecular gas is enriched in the isotope 13C, excluding the classification of the star as a Herbig Be. The observed isotopic abundance ratio (12C/13C = 25 ± 2) derived from our modeling is compatible with a proto-planetary nebula, main-sequence, or supergiant evolutionary phase. However, based on some observable characteristics of MWC 137, we propose that the supergiant scenario seems to be the most plausible. Hence, we suggest that MWC 137 could be in an extremely short-lived phase, evolving from a B[e] supergiant to a blue supergiant with a bipolar ring nebula. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), under program IDs GN-2011B-Q-24 and GN-2013B-Q-11.

  12. Evidence based administration of risperidone and paliperidone for the treating conduct disorder

    Directory of Open Access Journals (Sweden)

    Ahmad Ghanizadeh

    2013-01-01

    Full Text Available Background: This study evaluates the evidence-based administration of risperidone and paliperidone for the treating children and adolescents with conduct disorder (CD. Materials and Methods: A review of the current literature from clinical trials that investigated the efficacy of risperidone and paliperidone on CD considering the inclusion criteria and search strategies was performed by a search of PubMed and Google Scholar databases. Results: Out of 53 titles, 31 were irrelevant. The abstract of 22 potentially related articles were studied. Only six articles reported the results of clinical trial. However, one of them reported the effect of risperidone on conduct behaviors in autistic disorders. One study was a re-analysis of two previous studies, one study reported the effects of maintenance versus withdrawal of risperidone treatment and two studies included children with sub-average intelligence. Headache, somnolence and increased appetite are among the most common reported adverse effects. No study examined the effect of paliperidone on CD was found. Conclusion: Current literature suggests that risperidone could be effective for treating some conduct behaviors in children and adolescents. The effect of risperidone on CD is not a well-researched area. There is no well-controlled evidence based reports about the safety and efficacy of risperidone for the treatment of CD. Further trials should examine the efficacy of these medications on CD rather than conduct behaviors or disruptive behavior disorders.

  13. Microsphere Super-resolution Imaging

    CERN Document Server

    Wang, Zengbo

    2015-01-01

    Recently, it was discovered that microsphere can generate super-resolution focusing beyond diffraction limit. This has led to the development of an exciting super-resolution imaging technique -microsphere nanoscopy- that features a record resolution of 50 nm under white lights. Different samples have been directly imaged in high resolution and real time without labelling, including both non-biological (nano devices, structures and materials) and biological (subcellular details, viruses) samples. This chapter reviews the technique, which covers its background, fundamentals, experiments, mechanisms as well as the future outlook.

  14. ALMA observations of the supergiant B[e] star Wd1-9

    CERN Document Server

    Fenech, D; Prinja, R K; Morford, J C; Dougherty, S; Blomme, R

    2016-01-01

    Mass-loss in massive stars plays a critical role in their evolution, although the precise mechanism(s) responsible - radiatively driven winds, impulsive ejection and/or binary interaction -remain uncertain. In this paper we present ALMA line and continuum observations of the supergiant B[e] star Wd1-9, a massive post-Main Sequence object located within the starburst cluster Westerlund 1. We find it to be one of the brightest stellar point sources in the sky at millimetre wavelengths, with (serendipitously identified) emission in the H41alpha radio recombination line. We attribute these properties to a low velocity (~100 km/s) ionised wind, with an extreme mass-loss rate 6.4x10^-5(d/5kpc)^1.5 Msol/yr. External to this is an extended aspherical ejection nebula indicative of a prior phase of significant mass-loss. Taken together, the millimetre properties of Wd1-9 show a remarkable similarity to those of the highly luminous stellar source MWC349A.We conclude that these objects are interacting binaries evolving a...

  15. A White Light Megaflare on the dM4.5e Star YZ CMi

    CERN Document Server

    Kowalski, Adam F; Holtzman, Jon A; Wisniewski, John P; Hilton, Eric J

    2010-01-01

    On UT 2009 January 16, we observed a white light megaflare on the dM4.5e star YZ CMi as part of a long-term spectroscopic flare-monitoring campaign to constrain the spectral shape of optical flare continuum emission. Simultaneous U-band photometric and 3350A-9260A spectroscopic observations were obtained during 1.3 hours of the flare decay. The event persisted for more than 7 hours and at flare peak, the U-band flux was almost 6 magnitudes brighter than in the quiescent state. The properties of this flare mark it as one of the most energetic and longest-lasting white light flares ever to be observed on an isolated low-mass star. We present the U-band flare energetics and a flare continuum analysis. For the first time, we show convincingly with spectra that the shape of the blue continuum from 3350A to 4800A can be represented as a sum of two components: a Balmer continuum as predicted by the Allred et al radiative hydrodynamic flare models and a T ~ 10,000K blackbody emission component as suggested by many pr...

  16. Paliperidone ER and oral risperidone in patients with schizophrenia: a comparative database analysis

    Directory of Open Access Journals (Sweden)

    Schooler Nina

    2011-02-01

    Full Text Available Abstract Background To compare the efficacy and tolerability of paliperidone extended-release (ER with risperidone immediate-release using propensity score methodology. Methods Six double-blind, randomized, placebo-controlled, short-term clinical trials for acute schizophrenia with availability of individual patient-level data were identified (3 per compound. Propensity score pairwise matching was used to balance observed covariates between the paliperidone ER and risperidone patient populations. Scores were generated using logistic regression models, with age, body mass index, race, sex, baseline Positive and Negative Syndrome Scale (PANSS total score and baseline Clinical Global Impressions–Severity (CGI-S score as factors. The dosage range of paliperidone ER (6-12 mg/day was compared with 2 risperidone dosage ranges: 2-4 and 4-6 mg/day. The primary efficacy measure was change in PANSS total score at week 6 end point. Tolerability end points included adverse event (AE reports and weight. AEs with rates ≥5% and with a ≥2% difference between paliperidone ER and risperidone were identified. Results Completion rates for placebo-treated subjects in paliperidone ER trials (n = 95 and risperidone trials (n = 122 groups were 36.8% and 51.6%, respectively; end point changes on PANSS total scores were similar (p = 0.768. Completion rates for subjects receiving paliperidone ER 6-12 mg/day (n = 179, risperidone 2-4 mg/day (n = 113 or risperidone 4-6 mg/day (n = 129 were 64.8%, 54.0% and 66.7%, respectively (placebo-adjusted rates: paliperidone ER vs risperidone 2-4 mg/day, p = 0.005; paliperidone ER vs risperidone 4-6 mg/day, p = 0.159. PANSS total score improvement with paliperidone ER was greater than with risperidone 2-4 mg/day (difference in mean change score, -6.7; p Conclusions This indirect database analysis suggested that paliperidone ER 6-12 mg/day may be more efficacious than risperidone 2-4 mg/day and as efficacious as risperidone 4-6 mg

  17. Polymer microspheres with structured surfaces

    NARCIS (Netherlands)

    Wagdare, N.A.; Baggerman, J.; Marcelis, A.T.M.; Boom, R.M.; Rijn, van C.J.M.

    2011-01-01

    Microspheres from polymethyl methacrylate (PMMA) and Eudragit FS 30D (a commercial copolymer of poly(methyl acrylate-co-methyl methacrylate-co-methacrylic acid) 7:3:1) were prepared using microsieve emulsification. A mixture of these polymers in dichloromethane (DCM) was dispersed into water, leadin

  18. Optical trapping of coated microspheres

    NARCIS (Netherlands)

    Bormuth, V.; Jannasch, A.; Ander, M.; van Kats, C.M.; van Blaaderen, A.; Howard, J.; Schäffer, E.

    2008-01-01

    In an optical trap, micron-sized dielectric particles are held by a tightly focused laser beam. The optical force on the particle is composed of an attractive gradient force and a destabilizing scattering force. We hypothesized that using anti-reflection-coated microspheres would reduce scattering a

  19. A case study: neuroleptic malignant syndrome with risperidone and CYP2D6 gene variation.

    Science.gov (United States)

    Ochi, Shinichiro; Kawasoe, Koichiro; Abe, Masao; Fukuhara, Ryuji; Sonobe, Kantaro; Kawabe, Kentaro; Ueno, Shu-ichi

    2011-01-01

    We present a schizophrenic patient who experienced neuroleptic malignant syndrome with risperidone treatment due to variants of the CYP2D6 gene with reduced function. Clinicians need to be aware of this potential complication.

  20. Induction of Drug Transporters Alters Disposition of Risperidone - A Study in Mice

    Directory of Open Access Journals (Sweden)

    David Holthoewer

    2010-06-01

    Full Text Available Pharmacokinetic interactions, e.g. modulation of drug transporters like P-glycoprotein at the blood-brain barrier, can be a reason for treatment non-response. This study focuses on the influence of induction of drug transporters on the disposition of the antipsychotic drugs risperidone and 9-hydroxyrisperidone. Brain and serum concentrations of risperidone and its active metabolite 9-hydroxyrisperidone, which are known P-glycoprotein substrates, were measured after drug transporter induction with rifampicin, dexamethasone or 5-pregnene-3beta-ol-20-on-16alpha-carbonitrile using high performance liquid chromatography. Disposition of risperidone and 9-hydroxyrisperidone was dramatically decreased in mouse brain and serum after drug transporter induction. The metabolism of risperidone was also affected.

  1. 78 FR 52777 - Draft Guidance for Industry on Bioequivalence Recommendations for Risperidone Injection...

    Science.gov (United States)

    2013-08-26

    ... on Bioequivalence Recommendations for Risperidone Injection; Availability AGENCY: Food and Drug... provides specific recommendations on the design of bioequivalence (BE) studies to support abbreviated new... availability of a draft guidance for industry entitled ``Bioequivalence Recommendations for Specific...

  2. Serum prolactin levels and sexual dysfunctions in antipsychotic medication, such as risperidone : a review

    NARCIS (Netherlands)

    Knegtering, H; Lambers, PA; Prakken, G; ten Brink, C

    2000-01-01

    Classical antipsychotic drugs increase the level of serum prolactin. The atypical antipsychotic clozapine barely increases prolactin levels. An open naturalistic study in the University Hospital of Groningen suggests that treatment with risperidone in comparison to classical antipsychotics seems to

  3. Predominant role of the 9-hydroxy metabolite of risperidone in elevating blood prolactin levels

    NARCIS (Netherlands)

    Knegtering, R; Baselmans, P; Castelein, S; Bosker, F; Bruggeman, R; van den Bosch, RJ

    2005-01-01

    Objective: The atypical antipsychotic risperidone significantly raises plasma prolactin levels in patients, but clozapine, olanzapine, and quetiapine do not. The differences in neuroendocrine response may be connected with the metabolism of the medications. The authors examined the contributory role

  4. Development of novel risperidone implants using blends of polycaprolactones and in vitro in vivo correlation studies

    OpenAIRE

    2014-01-01

    The objective of this study was to develop a novel implant containing risperidone intended for long-term treatment in Schizophrenia utilizing in vitro in vivo correlation (IVIVC) studies. Different implants (F1-F8) containing an antipsychotic drug, risperidone, were prepared using a hot melt extrusion technique by taking polycaprolactones of different molecular weights (Mwt. 15000, 45000, 80000) either alone or as their blends, and PLGA (75:25). The implants contained 40% of the drug. After f...

  5. Combination treatment with risperidone long-acting injection and psychoeducational approaches for preventing relapse in schizophrenia

    Science.gov (United States)

    Zhao, Yueren; Kishi, Taro; Iwata, Nakao; Ikeda, Manabu

    2013-01-01

    A recent meta-analysis showed that long-acting injectable (LAI) antipsychotics were not superior to oral antipsychotics for preventing relapse in patients with schizophrenia. We therefore designed a treatment strategy combining risperidone LAI and COMPASS (COMprehensive Psycho-educational Approach and Scheme Set), an original psychoeducational program supporting treatment with risperidone LAI and evaluating subjective treatment satisfaction, transition of symptoms, and effectiveness in preventing symptomatic relapse. The aim of this study was to examine whether addition of COMPASS to risperidone LAI was more effective in preventing relapse in schizophrenia patients than risperidone LAI alone, with the latter group consisting of patients enrolled in a Phase III trial of risperidone LAI in Japan. Patients were followed up for 6 months, with COMPASS continuously implemented from the transition to the observation phase. The primary efficacy measurements were relapse rate (rates of rehospitalization and discontinuation due to inefficacy). Secondary efficacy measurements were the Brief Psychiatric Rating Scale (BPRS) and Global Assessment of Functioning (GAF) scores. Of the 96 patients originally enrolled, 19 (19.8%) were discontinued from all causes. During the 6-month study period, ten of the 96 patients (10.4%) relapsed, compared with a 12.2% relapse rate in patients enrolled in a Phase III trial of risperidone LAI in Japan. Patients showed significant improvements in BPRS total scores (P = 0.0031), BPRS positive (P = 0.0451), BRPS negative (P < 0.0001), and general subscale scores (P = 0.0031), and GAF (P < 0.0001) from baseline to 6 months. In conclusion, the lower relapse rate observed in patients treated with COMPASS plus risperidone LAI than in patients treated with risperidone LAI alone suggests that COMPASS may have benefits in the treatment of schizophrenia, indicating a need for randomized, controlled trials in larger numbers of patients. PMID:24194642

  6. Evaluation of potential pharmacokinetic drug-drug interaction between armodafinil and risperidone in healthy adults.

    Science.gov (United States)

    Darwish, Mona; Bond, Mary; Yang, Ronghua; Hellriegel, Edward T; Robertson, Philmore

    2015-11-01

    Patients with bipolar I disorder and schizophrenia have an increased risk of obstructive sleep apnea. The effects of armodafinil, a weak cytochrome P450 (CYP) 3A4 inducer, on pharmacokinetics and safety of risperidone, an atypical antipsychotic used to treat major psychiatric illness, were investigated. Healthy subjects received 2 mg risperidone alone and after armodafinil pretreatment (titrated to 250 mg/day). Pharmacokinetic parameters were derived from plasma concentrations of risperidone and its active metabolite, 9-hydroxyrisperidone (formed via CYP2D6 and CYP3A4), collected before and over 4 days after risperidone administration, and from steady-state plasma concentrations of armodafinil and its circulating metabolites, R-modafinil acid and modafinil sulfone. Safety and tolerability were assessed. Thirty-six subjects receiving study drug were evaluable for safety; 34 were evaluable for pharmacokinetics. Risperidone maximum plasma concentration (C max) decreased from mean 16.5 ng/mL when given alone to 9.2 ng/mL after armodafinil pretreatment (geometric mean ratio [90 % CI] 0.55 [0.50-0.61]); area under the plasma concentration-time curve from time 0 to infinity (AUC0-∞) decreased from 92.3 to 44.5 ng·h/mL (geometric mean ratio [90 % CI] 0.51 [0.46-0.55]). C max and AUC0-∞ for 9-hydroxyrisperidone were also reduced (geometric mean ratios [90 % CI] 0.81 [0.77-0.85] and 0.73 [0.69-0.77], respectively). Adverse events were consistent with known safety profiles. Consistent with CYP3A4 induction, risperidone and 9-hydroxyrisperidone systemic exposure was reduced in the presence of armodafinil. Concomitant armodafinil and risperidone use may necessitate risperidone dosage adjustment, particularly when starting or stopping coadministration of the two drugs. However, any such decision should be based on patient disease state and clinical status.

  7. A Comparison of Risperidone and Buspirone for Treatment of Behavior Disorders in Children with Phenylketonuria

    OpenAIRE

    FAYYAZi, Afshin; Salari, Elham; Ali KHAJEH; GAJARPOUR, Abdi

    2014-01-01

    How to Cite This Article: Fayyazi A, Salari E, Khajeh A, Ghajarpour A. A Comparison of Risperidone and Buspirone for Treatment ofBehavior Disorders in Children with Phenylketonuria. Iran J Child Neurol. 2014 Autumn; 8(4):33-38.AbstractObjectiveMany patients with late-diagnosed phenylketonuria (PKU) suffer from severe behavior problems. This study compares the effects of buspirone and risperidone on reducing behavior disorders in these patients.Materials & MethodsIn this crossover clinical...

  8. ERYTHROMYCIN POLYLACTIC ACID MICROSPHERES FOR LUNG TARGETING

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    AIM: To prepare polylactic acid microspheres of Erythromycin for Lung targeting.METHEDS: The orthogonal test design was used to optimize the technology,of preparation. Thecharacter of the microspheres, drug release in vitro, stability and tissue distribution were examinedRESULTS: The Erythromycin polylactic acid microspheres was regular in its morphology. Drugwas enveloped in microspheres but not physically mixed with PDLLA. The average particle size was11.65μn with over 94% of the microspheres being in the range of 5~20trn; The drug loading andthe incorporation efciency were 18% and 60% respectively. The microspheres were stable for threemonth at 4 ℃ and room temperature. The in vitro release properties could be expressed by theHiguchi's equation: y = 28.067 + 3.8515t11/2 (r = 0.9834). Comparing with injection, the drug inmicrospheres was more concentrated in lung tissue. CONCLUSION: Erythromycin polylactic acidmicrospheres showed significant sustained release and lung targeting.

  9. Comparing Efficacy and Side Effects of Memantine vs. Risperidone in the Treatment of Autistic Disorder.

    Science.gov (United States)

    Nikvarz, Nikvarz; Alaghband-Rad, Javad; Tehrani-Doost, Mehdi; Alimadadi, Abbas; Ghaeli, Padideh

    2017-01-01

    Introduction: This study was aimed to compare the efficacy and side effects of memantine, an antagonist of the NMDA receptor of glutamate, with risperidone given the fact that glutamate has been noted for its possible effects in the pathogenesis of autism. Risperidone, an atypical antipsychotic, has been approved by FDA for the management of irritability associated with autism. Methods: 30 children, aged 4-17 years, entered an 8-week, randomized trial. Patients were randomly assigned to receive either risperidone or memantine. Autism Behavior Checklist (ABC), Childhood Autism Rating Scale (CARS), Clinical Global Impressions - Improvement (CGI-I) and Clinical Global Impression-Severity (CGI-S) scales were used to assess behavioral symptoms of the patients. Results: Both risperidone and memantine reduced the scores of 4 subscales of ABC as well as the 10-item and the total score of CARS significantly. However, differences between the 2 drugs in the scores of each evaluating scale were not found to be significant. Relatively, larger number of patients on risperidone showed "very much improvement" when assessed by CGI-I scale when compared with those on memantine. Discussion and conclusion: The present study suggests that memantine may have beneficial effects in the treatment of many core symptoms of autism. Therefore, memantine may be considered as a potential medication in the treatment of those autistic children who do not respond or cannot tolerate side effects of risperidone.

  10. Treatment with the antipsychotic agent, risperidone, reduces disease severity in experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    O'Sullivan, David; Green, Laura; Stone, Sarrabeth; Zareie, Pirooz; Kharkrang, Marie; Fong, Dahna; Connor, Bronwen; La Flamme, Anne Camille

    2014-01-01

    Recent studies have demonstrated that atypical antipsychotic agents, which are known to antagonize dopamine D2 and serotonin 5-HT2a receptors, have immunomodulatory properties. Given the potential of these drugs to modulate the immune system both peripherally and within the central nervous system, we investigated the ability of the atypical anti-psychotic agent, risperidone, to modify disease in the animal model of multiple sclerosis (MS)4, experimental autoimune encephalomyelitis (EAE). We found that chronic oral administration of risperidone dose-dependently reduced the severity of disease and decreased both the size and number of spinal cord lesions. Furthermore, risperidone treatment substantially reduced antigen-specific interleukin (IL)-17a, IL-2, and IL-4 but not interferon (IFN)-γ production by splenocytes at peak disease and using an in vitro model, we show that treatment of macrophages with risperidone alters their ability to bias naïve T cells. Another atypical antipsychotic agent, clozapine, showed a similar ability to modify macrophages in vitro and to reduce disease in the EAE model but this effect was not due to antagonism of the type 1 or type 2 dopamine receptors alone. Finally, we found that while risperidone treatment had little effect on the in vivo activation of splenic macrophages during EAE, it significantly reduced the activation of microglia and macrophages in the central nervous system. Together these studies indicate that atypical antipsychotic agents like risperidone are effective immunomodulatory agents with the potential to treat immune-mediated diseases such as MS.

  11. Treatment of aggression with risperidone in children and adolescents with bipolar disorder: a case series.

    Science.gov (United States)

    Saxena, Kirti; Chang, Kiki; Steiner, Hans

    2006-08-01

    To evaluate the effectiveness and safety of risperidone in children and adolescents with bipolar disorder characterized by aggression and mania, despite treatment with mood stabilizers. A retrospective chart review of patients seen in an outpatient pediatric mood disorders clinic over an 18-month period was performed. Data were extracted from charts of patients who had a diagnosis of bipolar disorder with aggression that was uncontrolled on a mood stabilizer; as a result, these patients had risperidone added to their regimen. Four boys (aged 7-15 years) and two girls (aged 8 and 14 years) were treated with risperidone (mean dosage, 0.85 mg/day) for 3-16 months. Aggressive behavior improved in all patients after risperidone was started and remained improved for the duration of follow-up. Other symptoms of mania also improved. Risperidone was generally well tolerated. Sedation and akathisia were reported in one patient. The addition of risperidone to a mood stabilizer may improve aggression and other symptoms of mania in pediatric patients with bipolar disorder who do not respond adequately to a mood stabilizer alone. The long-term efficacy and safety of this regimen should be evaluated in a controlled clinical trial.

  12. Galactorrhea - side effect of risperidone in combination with depakine chrono in a patient with bipolar disorder.

    Science.gov (United States)

    Peitl, Marija Vucić; Peitl, Vjekoslav; Grahovac, Tanja; Pavlović, Eudard

    2010-03-01

    Risperidone, as all atypical antipsychotics, can cause hyperprolactinemia which can in turn lead to galactorrhea. Mood stabilizers, one of which is valproic acid and its derivate "Depakine Chrono", are rarely linked with symptomatic hyperprolactinemia and do not alter prolactin concentrations. This case is based around a patient suffering from a bipolar disorder that has been psychiatrically treated in an outpatient clinic during four years. Bipolar disorder treatment was started with carbamazepine, but later it was discontinued due to adverse events and extreme increase of liver transaminases. Treatment was continued with introduction of lithium, but the patient stated that she could not tolerate it. Subsequently, her endocrinologist advised for lithium discontinuation due to very severe osteoporosis. At the beginning of 2009, lithium was discontinued and Depakine Chrono was introduced. Due to patient's psychotic decompensation it was necessary to introduce risperidone into treatment and soon afterwards her psychotic symptoms settled. After several months of treatment her mood lowered, she began to feel sedated, psychomotorically retarded and that lead to dose lowering of Depakine Chrono and risperidone, at which point galactorrhea as a serious adverse event occurred. Occurrence of galactorrhea at lower risperidone doses in this case might be partially explained by recent studies that showed that lower doses of risperidone can also improve psychic state, but could also cause adverse events. Although galactorrhea, as a direct consequence of hyperprolactinemia caused by risperidone has mainly been researched with higher doses of this atypical antipsychotic, we have to keep in mind that lower doses could also cause serious adverse events.

  13. A Comparative Study between Olanzapine and Risperidone in the Management of Schizophrenia

    Directory of Open Access Journals (Sweden)

    Saeed Shoja Shafti

    2014-01-01

    Full Text Available Introduction. Since a variety of comparisons between risperidone and olanzapine have resulted in diverse outcomes, so safety and efficacy of them were compared again in a new trial. Method. Sixty female schizophrenic patients entered into one of the assigned groups for random allocation to olanzapine or risperidone (n=30 in each group in a double-blind, 12-week clinical trial. Scale for Assessment of Positive Symptoms (SAPS and Scale for Assessment of Negative Symptoms (SANS were used as the primary outcome measures. Clinical Global Impressions-Severity Scale (CGI-S, Schedule for Assessment of Insight (SAI, and finally Simpson Angus Scale (SAS as well were employed as secondary scales. Results. While both of olanzapine and risperidone were significantly effective for improvement of positive symptoms (P<0.0001, as regards negative symptoms, it was so only by means of olanzapine (P<0.0003. CGI-S and SAI, as well, were significantly improved in both of the groups. SAS increment was significant only in the risperidone group (P<0.02. Conclusion. While both of olanzapine and risperidone were equally effective for improvement of positive symptoms and insight, olanzapine showed superior efficacy with respect to negative symptoms, along with lesser extrapyramidal side effects, in comparison with risperidone.

  14. Magnetoresponsive Photonic Microspheres with Structural Color Gradient.

    Science.gov (United States)

    Lee, Seung Yeol; Choi, Jongkook; Jeong, Jong-Ryul; Shin, Jung H; Kim, Shin-Hyun

    2017-02-06

    Photonic Janus particles are created by alternately sputtering silica and titania on microspheres in order to obtain a structural color gradient. In addition, the microspheres are rendered magnetoresponsive. The Janus microspheres with optical and magnetic anisotropy enable on-demand control over orientation and structural color through manipulation of an external magnetic field, thereby being useful as active color pigments for reflection-mode displays.

  15. Early onset of treatment effects with oral risperidone

    Directory of Open Access Journals (Sweden)

    Naber Dieter

    2007-01-01

    Full Text Available Abstract Background The dogma of a delayed onset of antipsychotic treatment effects has been maintained over the past decades. However, recent studies have challenged this concept. We therefore performed an analysis of the onset of antipsychotic treatment effects in a sample of acutely decompensated patients with schizophrenia. Methods In this observational study, 48 inpatients with acutely decompensated schizophrenia were offered antipsychotic treatment with oral risperidone. PANSS-ratings were obtained on day 0, day 1, day 3, day 7 and day 14. Results Significant effects of treatment were already present on day 1 and continued throughout the study. The PANSS positive subscore and the PANSS total score improved significantly more than the PANSS negative subscore. Conclusion Our results are consistent with the growing number of studies suggesting an early onset of antipsychotic treatment effects. However, non-pharmacological effects of treatment also need to be taken into consideration.

  16. The supergiant B[e] star LHA 115-S 18 - binary and/or luminous blue variable?

    Science.gov (United States)

    Clark, J. S.; Bartlett, E. S.; Coe, M. J.; Dorda, R.; Haberl, F.; Lamb, J. B.; Negueruela, I.; Udalski, A.

    2013-12-01

    Context. The mechanism by which supergiant (sg)B[e] stars support cool, dense dusty discs/tori and their physical relationship with other evolved, massive stars such as luminous blue variables is uncertain. Aims: In order to investigate both issues we have analysed the long term behaviour of the canonical sgB[e] star LHA 115-S 18. Methods: We employed the OGLE II-IV lightcurve to search for (a-)periodic variability and supplemented these data with new and historic spectroscopy. Results: In contrast to historical expectations for sgB[e] stars, S18 is both photometrically and spectroscopically highly variable. The lightcurve is characterised by rapid aperiodic "flaring" throughout the 16 years of observations. Changes in the high excitation emission line component of the spectrum imply evolution in the stellar temperature - as expected for luminous blue variables - although somewhat surprisingly, spectroscopic and photometric variability appears not to be correlated. Characterised by emission in low excitation metallic species, the cool circumstellar torus appears largely unaffected by this behaviour. Finally, in conjunction with intense, highly variable He ii emission, X-ray emission implies the presence of an unseen binary companion. Conclusions: S18 provides observational support for the putative physical association of (a subset of) sgB[e] stars and luminous blue variables. Given the nature of the circumstellar environment of S18 and that luminous blue variables have been suggested as supernovae progenitors, it is tempting to draw a parallel to the progenitors of SN1987A and SN2009ip. Moreover the likely binary nature of S18 strengthens the possibility that the dusty discs/tori that characterise sgB[e] stars are the result of binary-driven mass-loss; consequently such stars may provide a window on the short lived phase of mass-transfer in massive compact binaries. This work is partly based on observations collected at the European Southern Observatory (programme

  17. Compression molding of aerogel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Pekala, Richard W. (Pleasant Hill, CA); Hrubesh, Lawrence W. (Pleasanton, CA)

    1998-03-24

    An aerogel composite material produced by compression molding of aerogel microspheres (powders) mixed together with a small percentage of polymer binder to form monolithic shapes in a cost-effective manner. The aerogel composites are formed by mixing aerogel microspheres with a polymer binder, placing the mixture in a mold and heating under pressure, which results in a composite with a density of 50-800 kg/m.sup.3 (0.05-0.80 g/cc). The thermal conductivity of the thus formed aerogel composite is below that of air, but higher than the thermal conductivity of monolithic aerogels. The resulting aerogel composites are attractive for applications such as thermal insulation since fabrication thereof does not require large and expensive processing equipment. In addition to thermal insulation, the aerogel composites may be utilized for filtration, ICF target, double layer capacitors, and capacitive deionization.

  18. Compression molding of aerogel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Pekala, R.W.; Hrubesh, L.W.

    1998-03-24

    An aerogel composite material produced by compression molding of aerogel microspheres (powders) mixed together with a small percentage of polymer binder to form monolithic shapes in a cost-effective manner is disclosed. The aerogel composites are formed by mixing aerogel microspheres with a polymer binder, placing the mixture in a mold and heating under pressure, which results in a composite with a density of 50--800 kg/m{sup 3} (0.05--0.80 g/cc). The thermal conductivity of the thus formed aerogel composite is below that of air, but higher than the thermal conductivity of monolithic aerogels. The resulting aerogel composites are attractive for applications such as thermal insulation since fabrication thereof does not require large and expensive processing equipment. In addition to thermal insulation, the aerogel composites may be utilized for filtration, ICF target, double layer capacitors, and capacitive deionization. 4 figs.

  19. Observational constraints for the circumstellar disk of the B[e] star CPD-52 9243

    Science.gov (United States)

    Cidale, L. S.; Borges Fernandes, M.; Andruchow, I.; Arias, M. L.; Kraus, M.; Chesneau, O.; Kanaan, S.; Curé, M.; de Wit, W. J.; Muratore, M. F.

    2012-12-01

    Context. The formation and evolution of gas and dust environments around B[e] supergiants are still open issues. Aims: We intend to study the geometry, kinematics and physical structure of the circumstellar environment (CE) of the B[e] supergiant CPD-52 9243 to provide further insights into the underlying mechanism causing the B[e] phenomenon. Methods: The influence of the different physical mechanisms acting on the CE (radiation pressure, rotation, bi-stability or tidal forces) is somehow reflected in the shape and kinematic properties of the gas and dust regions (flaring, Keplerian, accretion or outflowing disks). To investigate these processes we mainly used quasi-simultaneous observations taken with high spatial resolution optical long-baseline interferometry (VLTI/MIDI), near-IR spectroscopy of CO bandhead features (Gemini/Phoenix and VLT/CRIRES) and optical spectra (CASLEO/REOSC). Results: High angular resolution interferometric measurements obtained with VLTI/MIDI provide strong support for the presence of a dusty disk(ring)-like structure around CPD-52 9243, with an upper limit for its inner edge of ~8 mas (~27.5 AU, considering a distance of 3.44 kpc to the star). The disk has an inclination angle with respect to the line of sight of 46 ± 7°. The study of CO first overtone bandhead evidences a disk structure in Keplerian rotation. The optical spectrum indicates a rapid outflow in the polar direction. Conclusions: The IR emission (CO and warm dust) indicates Keplerian rotation in a circumstellar disk while the optical line transitions of various species are consistent with a polar wind. Both structures appear simultaneously and provide further evidence for the proposed paradigms of the mass-loss in supergiant B[e] stars. The presence of a detached cold CO ring around CPD-52 9243 could be due to a truncation of the inner disk caused by a companion, located possibly interior to the disk rim, clearing the center of the system. More spectroscopic and

  20. Microspheres in Plasma Display Panels

    Science.gov (United States)

    2006-01-01

    Filling small bubbles of molten glass with gases is just as difficult as it sounds, but the technical staff at NASA is not known to shy away from a difficult task. When Microsphere Systems, Inc. (MSI), of Ypsilanti, Michigan, and Imaging Systems Technology, Inc. (IST), of Toledo, Ohio, were trying to push the limits of plasma displays but were having difficulty with the designs, NASA s Glenn Garrett Morgan Commercialization Initiative (GMCI) assembled key personnel at Glenn Research Center and Ohio State University for a brainstorming session to come up with a solution for the companies. They needed a system that could produce hollow, glass micro-sized spheres (microspheres) that could be filled with a variety of gasses. But the extremely high temperature required to force the micro-sized glass bubbles to form at the tip of a metal nozzle resulted in severe discoloration of the microspheres. After countless experiments on various glass-metal combinations, they had turned to the GMCI for help. NASA experts in advanced metals, ceramics, and glass concluded that a new design approach was necessary. The team determined that what was needed was a phosphate glass composition that would remain transparent, and they went to work on a solution. Six weeks later, using the design tips from the NASA team, Tim Henderson, president of MSI, had designed a new system in which all surfaces in contact with the molten glass would be ceramic instead of metal. Meanwhile, IST was able to complete a Phase I Small Business Innovation Research (SBIR) grant supported by the National Science Foundation (NSF) and supply a potential customer with samples of the microspheres for evaluation as filler materials for high-performance insulations.

  1. Glass microspheres for medical applications

    Science.gov (United States)

    Conzone, Samuel David

    Radioactive dysprosium lithium borate glass microspheres have been developed as biodegradable radiation delivery vehicles for the radiation synovectomy treatment of rheumatoid arthritis. Once injected into a diseased joint, the microspheres deliver a potent dose of radiation to the diseased tissue, while a non-uniform chemical reaction converts the glass into an amorphous, porous, hydrated dysprosium phosphate reaction product. The non-radioactive, lithium-borate component is dissolved from the glass (up to 94% weight loss), while the radioactive 165Dy reacts with phosphate anions in the body fluids, and becomes "chemically" trapped in a solid, dysprosium phosphate reaction product that has the same size as the un-reacted glass microsphere. Ethylene diamine tetraacetate (EDTA) chelation therapy can be used to dissolve the dysprosium phosphate reaction product after the radiation delivery has subsided. The dysprosium phosphate reaction product, which formed in vivo in the joint of a Sprague-Dawley rat, was dissolved by EDTA chelation therapy in 100 Gy) of localized beta radiation to a treatment site within the body, followed by complete biodegradability. The non-uniform reaction process is a desirable characteristic for a biodegradable radiation delivery vehicle, but it is also a novel material synthesis technique that can convert a glass to a highly porous materials with widely varying chemical composition by simple, low-temperature, glass/solution reaction. The reaction product formed by nonuniform reaction occupies the same volume as the un-reacted glass, and after drying for 1 h at 300°C, has a specific surface area of ≈200 m2/g, a pore size of ≈30 nm, and a nominal crushing strength of ≈10 MPa. Finally, rhenium glass microspheres, composed of micron-sized, metallic rhenium particles dispersed within a magnesium alumino borate glass matrix were produced by sintering ReO2 powder and glass frit at 1050°C. A 50 mg injection of radioactive rhenium glass

  2. A Randomized Open Label Comparison of the Effects ofRisperidone and Haloperidol on Sexual Function

    Directory of Open Access Journals (Sweden)

    S. Jaber Mousavi

    2009-12-01

    Full Text Available "n Objective: "nSexual dysfunction in patients who take antipsychotics causes adecline in their quality of life and medication acceptance. Considering the restrictions in cross sectional design of many earlier researches, we used a clinical trial aimed at assessing sexual dysfunction by substituting Risperidone, an atypical antipsychotic drug, with Haloperidol, a typical one . "n "n "nMethod: This clinical trial was conducted on 51 patients who had been using Risperidone with a minimum dose of 2 mg/daily for at least 2 months. The patients were randomly divided into 2 groups. The first group continued taking Risperidone, whereas the second group was given Haloperidol. Sexual function prior to and after the drug substitution was assessed using a sexual questionnaire designed to assess four stages of sexual function . "nResults: Compared to those who changed their medication to Haloperidol, the patients who remained on Risperidone therapy suffered from more sexual dysfunction, especially in their tendency towards having sexual activities (P= 0.01, post menstrual sexual activity (P= 0.002, and reaching orgasm in their sexual activities (P= 0.04; however in the Haloperidol group, no significant difference was observed before and after the change in medication . "nConclusion: Although Risperidone and Haloperidol can both disturb patients'sexual function, the side effects of Risperidone are stronger. Hence toprevent the decline of medication acceptance or irregular consumption by patients which may lead to possible relapse, substitution of Risperidone withanother drug with fewer side effects on sexual activities is definitely to the advantage of the patients .

  3. CYP2D6 polymorphisms and their influence on risperidone treatment

    Directory of Open Access Journals (Sweden)

    Puangpetch A

    2016-12-01

    Full Text Available Apichaya Puangpetch,1 Natchaya Vanwong,1 Nopphadol Nuntamool,2 Yaowaluck Hongkaew,1 Monpat Chamnanphon,1 Chonlaphat Sukasem1 1Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, 2Molecular Medicine, Faculty of Science, Mahidol University, Bangkok, Thailand Abstract: Cytochrome P450 enzyme especially CYP2D6 plays a major role in biotransformation. The interindividual variations of treatment response and toxicity are influenced by the polymorphisms of this enzyme. This review emphasizes the effect of CYP2D6 polymorphisms in risperidone treatment in terms of basic knowledge, pharmacogenetics, effectiveness, adverse events, and clinical practice. Although the previous studies showed different results, the effective responses in risperidone treatment depend on the CYP2D6 polymorphisms. Several studies suggested that CYP2D6 polymorphisms were associated with plasma concentration of risperidone, 9-hydroxyrisperidone, and active moiety but did not impact on clinical outcomes. In addition, CYP2D6 poor metabolizer showed more serious adverse events such as weight gain and prolactin than other predicted phenotype groups. The knowledge of pharmacogenomics of CYP2D6 in risperidone treatment is increasing, and it can be used for the development of personalized medication in term of genetic-based dose recommendation. Moreover, the effects of many factors in risperidone treatment are still being investigated. Both the CYP2D6 genotyping and therapeutic drug monitoring are the important steps to complement the genetic-based risperidone treatment. Keywords: CYP2D6, risperidone, polymorphisms, adverse drug reaction, pharmacogenetics, pharmacokinetics, pharmacodynamics

  4. POROUS WALL, HOLLOW GLASS MICROSPHERES

    Energy Technology Data Exchange (ETDEWEB)

    Sexton, W.

    2012-06-30

    Hollow Glass Microspheres (HGM) is not a new technology. All one has to do is go to the internet and Google{trademark} HGM. Anyone can buy HGM and they have a wide variety of uses. HGM are usually between 1 to 100 microns in diameter, although their size can range from 100 nanometers to 5 millimeters in diameter. HGM are used as lightweight filler in composite materials such as syntactic foam and lightweight concrete. In 1968 a patent was issued to W. Beck of the 3M{trademark} Company for 'Glass Bubbles Prepared by Reheating Solid Glass Particles'. In 1983 P. Howell was issued a patent for 'Glass Bubbles of Increased Collapse Strength' and in 1988 H. Marshall was issued a patent for 'Glass Microbubbles'. Now Google{trademark}, Porous Wall, Hollow Glass Microspheres (PW-HGMs), the key words here are Porous Wall. Almost every article has its beginning with the research done at the Savannah River National Laboratory (SRNL). The Savannah River Site (SRS) where SRNL is located has a long and successful history of working with hydrogen and its isotopes for national security, energy, waste management and environmental remediation applications. This includes more than 30 years of experience developing, processing, and implementing special ceramics, including glasses for a variety of Department of Energy (DOE) missions. In the case of glasses, SRS and SRNL have been involved in both the science and engineering of vitreous or glass based systems. As a part of this glass experience and expertise, SRNL has developed a number of niches in the glass arena, one of which is the development of porous glass systems for a variety of applications. These porous glass systems include sol gel glasses, which include both xerogels and aerogels, as well as phase separated glass compositions, that can be subsequently treated to produce another unique type of porosity within the glass forms. The porous glasses can increase the surface area compared to &apos

  5. ERYTHROMYCIN POLYLACTIC ACID MICROSPHERES FOR LUNG TARGETING

    Institute of Scientific and Technical Information of China (English)

    YANGFan; YANBing; 等

    2002-01-01

    AIM:To prepare polylactiv acid microspheres of Erythromycin for Lung targeting.METHEDS:The orthogonal test design was used to optimize the technology of preparation.The character of the microspheres,drug release in vitro,stabiligy and tissue distribution were examined. RESULTS:The Erythromycin polylatic acid microspheres was regular in its morphology.Drug was enveloped in microspheres but not physically mixed with PDLLA.The average particle size was 11.65μm with over 94% of the microspheres being in the range of 5-20μm;The drug loading and the incorporation efficiency were 18% and 60% respectively.The microspheres were stable for three month at 4℃ and room temperature.The in vitro release properties could be expressed by the Higuchi′s equation:y=28.067+3.8515t1/2(r=0.9834).Comparing with injection,the drug in microspheres was more concentrated in lung tissue.CONLUSION:Erythromycin polylactic acid microspheres showed significant sustained release and lung targeting.

  6. Assembly of ordered magnetic microsphere arrays

    Science.gov (United States)

    Xu, Wanling; Ketterson, John

    2008-08-01

    We have developed a straightforward technique to assemble ordered arrays of magnetic microspheres on patterned thin Permalloy (Py) films deposited on the surface of a silicon wafer. Droplets containing micrometer-sized carboxyl paramagnetic microspheres are placed on a horizontally oriented wafer. The field produced by a permanent magnet placed under the wafer is rendered inhomogeneous by the patterned Py features and the resulting field gradients attract and hold the paramagnetic microspheres to these features. While the magnetic microspheres are being attracted to and secured on the pattered Permalloy features, a horizontal flow is created by a pipette, which also removes loose (unsecured) microspheres. By applying this technique to a cocktail of individually functionalized microspheres, a sensor could be realized, which will screen, in parallel, for a large number of targets per unit area. The ability to resolve individual microspheres is close to 100%. A desirable feature is that the substrate is reusable; removing the magnet allows an existing batch of microspheres, which may have lost sensitivity due to environmental exposure, to be flushed from the substrate and replaced with a new batch. The technique complements existing approaches in the field of microarrays widely used in immunoassay, DNA fragment detection, pathogen detection, and other applications in functional genomics and diagnostics.

  7. Microencapsulation and microspheres for food applications

    NARCIS (Netherlands)

    Sagis, L.M.C.

    2015-01-01

    This book provides an update on the latest developments, challenges, and opportunities in the highly expanding field of microencapsulation and microspheres for food applications, examining the various types of microspheres and microcapsules essential to those who need to develop stable and impermeab

  8. Dextran-based microspheres as controlled delivery systems for proteins

    NARCIS (Netherlands)

    Vlugt-Wensink, K.D.F.

    2007-01-01

    Dextran-based microspheres as controlled delivery systems for proteins Dextran based microspheres are investigated as controlled delivery system for proteins. Microspheres were prepared by polymerization of dex-HEMA in an aqueous two-phase system of dex-HEMA and PEG. Protein loaded microspheres are

  9. Spectrally resolved resonant propulsion of dielectric microspheres

    CERN Document Server

    Li, Yangcheng; Limberopoulos, Nicholaos I; Urbas, Augustine M; Astratov, Vasily N

    2015-01-01

    Use of resonant light forces opens up a unique approach to high-volume sorting of microspherical resonators with much higher uniformity of resonances compared to that in coupled-cavity structures obtained by the best semiconductor technologies. In this work, the spectral response of the propulsion forces exerted on polystyrene microspheres near tapered microfibers is directly observed. The measurements are based on the control of the detuning between the tunable laser and internal resonances in each sphere with accuracy higher than the width of the resonances. The measured spectral shape of the propulsion forces correlates well with the whispering-gallery mode resonances in the microspheres. The existence of a stable radial trap for the microspheres propelled along the taper is demonstrated. The giant force peaks observed for 20-{\\mu}m spheres are found to be in a good agreement with a model calculation demonstrating an efficient use of the light momentum for propelling the microspheres.

  10. Hydroxyapatite nanocrystal coating on biodegradable microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Masahiro [Department of Bioengineering, Advanced Medical Engineering Center, National Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita, Osaka 565-8565 (Japan); Furuzono, Tsutomu, E-mail: furuzono@ri.ncvc.go.jp [Department of Bioengineering, Advanced Medical Engineering Center, National Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita, Osaka 565-8565 (Japan)

    2010-10-15

    Nano-sized single crystals of calcined hydroxyapatite (HAp) were uniformly coated on poly(L-lactic acid) (PLLA) microspheres through the ionic interaction between calcium ions on the HAp nanocrystal and carboxyl groups on the PLLA microsphere. In order to coat the substrate with HAp nanocrystals through ionic interaction, the surfaces of the PLLA microspheres were hydrolyzed in an alkaline aqueous solution at pH 11.0 for 1 h at room temperature. The interaction between the HAp nanocrystals and the carboxyl groups originating from PLLA end groups was estimated by Fourier transform infrared spectroscopy. The alkali-treated PLLA microspheres were coated with HAp nanocrystals by immersing the microspheres in an ethanol dispersion of HAp nanocrystals followed by washing in an ultrasonic bath.

  11. Biofunctionalization of silica microspheres for protein separation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Binjie [Institute of Immunology, Henan University, Kaifeng 475004 (China); Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Zou, Xueyan [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Zhao, Yanbao, E-mail: yanbaozhao@126.com [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Sun, Lei [Institute of Immunology, Henan University, Kaifeng 475004 (China); Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Li, Shulian [Institute of Immunology, Henan University, Kaifeng 475004 (China)

    2013-07-01

    Mercapto-silica (SiO{sub 2}–SH) microspheres were prepared via direct hydrolysis of 3-mercaptopropyltrimethoxysilane (MPS) in a basic aqueous solution. The content of surface thiol group (-SH) of SiO{sub 2}–SH microspheres was measured by Ellman's reagent method and X-ray photoelectron spectroscopy (XPS) and the content of surface thiol group of SiO{sub 2}–SH microspheres is strongly dependent on the reaction conditions. The thermal stability of SiO{sub 2}–SH microspheres was evaluated by thermogravimetric (TG) analysis, which tended to reduce with the increase of content of surface thiol groups. SiO{sub 2}–SH microspheres can be easily modified with reduced glutathione (GSH) to generate SiO{sub 2}–GSH microspheres for the affinity separation of Glutathione S-transferase (GST). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed to examine the validity of the separation procedure. The results showed that SiO{sub 2}–GSH microspheres were efficient in GST affinity separation from mixed proteins. - Graphical abstract: The prepared SiO{sub 2}–SH microsphere binding reduced glutathione (SiO{sub 2}–GSH) as affinity precipitation support can capture selectively Glutathione S-transferase (GST) from mixed protein solution. Highlights: ► SiO{sub 2}–SH microspheres were prepared in water using one-pot synthesis. ► The content of surface -SH was investigated by Ellman method and XPS spectra. ► The ratio of -SH to mass strongly depends on the reaction conditions. ► SiO{sub 2}–SH microspheres were biofunctionalized by glutathione. ► SiO{sub 2}–GSH can be used to capture selectively Glutathione S-transferase.

  12. Combination treatment with risperidone long-acting injection and psychoeducational approaches for preventing relapse in schizophrenia

    Directory of Open Access Journals (Sweden)

    Zhao Y

    2013-10-01

    Full Text Available Yueren Zhao,1–3 Taro Kishi,1 Nakao Iwata,1 Manabu Ikeda3,4 1Department of Psychiatry, Fujita Health University School of Medicine, Toyoake, Aichi, Japan; 2Department of Psychiatry, Okehazama Hospital Fujita Kokoro Care Center, Toyoake, Aichi, Japan; 3Department of Neuropsychiatry, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Kumamoto, Japan; 4Department of Neuropsychiatry, Faculty of Life Sciences, Kumamoto University, Kumamoto, Kumamoto, Japan Abstract: A recent meta-analysis showed that long-acting injectable (LAI antipsychotics were not superior to oral antipsychotics for preventing relapse in patients with schizophrenia. We therefore designed a treatment strategy combining risperidone LAI and COMPASS (COMprehensive Psycho-educational Approach and Scheme Set, an original psychoeducational program supporting treatment with risperidone LAI and evaluating subjective treatment satisfaction, transition of symptoms, and effectiveness in preventing symptomatic relapse. The aim of this study was to examine whether addition of COMPASS to risperidone LAI was more effective in preventing relapse in schizophrenia patients than risperidone LAI alone, with the latter group consisting of patients enrolled in a Phase III trial of risperidone LAI in Japan. Patients were followed up for 6 months, with COMPASS continuously implemented from the transition to the observation phase. The primary efficacy measurements were relapse rate (rates of rehospitalization and discontinuation due to inefficacy. Secondary efficacy measurements were the Brief Psychiatric Rating Scale (BPRS and Global Assessment of Functioning (GAF scores. Of the 96 patients originally enrolled, 19 (19.8% were discontinued from all causes. During the 6-month study period, ten of the 96 patients (10.4% relapsed, compared with a 12.2% relapse rate in patients enrolled in a Phase III trial of risperidone LAI in Japan. Patients showed significant improvements in BPRS total

  13. Risperidone Improves Behavioral Symptoms in Children with Autism in a Randomized, Double-Blind, Placebo-Controlled Trial

    Science.gov (United States)

    Pandina, Gahan J.; Bossie, Cynthia A.; Youssef, Eriene; Zhu, Young; Dunbar, Fiona

    2007-01-01

    Subgroup analysis of children (5-12 years) with autism enrolled in an 8-week, double-blind, placebo-controlled trial of risperidone for pervasive developmental disorders. The primary efficacy measure was the Aberrant Behavior Checklist-Irritability (ABC-I) subscale. Data were available for 55 children given risperidone (n = 27) or placebo (n =…

  14. Risperidone Dosing in Children and Adolescents with Autistic Disorder: A Double-Blind, Placebo-Controlled Study

    Science.gov (United States)

    Kent, Justine M.; Kushner, Stuart; Ning, Xiaoping; Karcher, Keith; Ness, Seth; Aman, Michael; Singh, Jaskaran; Hough, David

    2013-01-01

    Efficacy and safety of 2 risperidone doses were evaluated in children and adolescents with autism. Patients (N = 96; 5-17 years), received risperidone (low-dose: 0.125 mg/day [20 to 45 kg] or high-dose: 1.25 mg/day [20 to 45 kg]) or placebo. Mean baseline (range 27-29) to endpoint change…

  15. Risperidone – Solid-state characterization and pharmaceutical compatibility using thermal and non-thermal techniques

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Josiane Souza Pereira; Veronez, Isabela Pianna; Rodrigues, Larissa Lopes [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil); Trevisan, Marcello G. [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil); National Institute of Bioanalytics Science and Technology – INCTBio, Institute of Chemistry – UNICAMP, 13084-653, Campinas, São Paulo (Brazil); Garcia, Jerusa Simone, E-mail: jerusa.garcia@unifal-mg.edu.br [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil)

    2013-09-20

    Highlights: • DSC was used to characterize Risperidone and study its compatibility with excipients. • FT-IR associated with PCA was used to complement DSC data. • LC analyzes confirmed the DSC and FT-IR/PCA results. • Risperidone was incompatible with three among five excipients evaluated. - Abstract: A full solid-state characterization of risperidone was conducted using differential scanning calorimetry (DSC), thermogravimetry (TG), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) to examine its physicochemical properties and polymorphism. The primary aim of this work was to study the compatibility of risperidone with pharmaceutical excipients using DSC to obtain and compare the curves of the active pharmaceutical ingredient (API) and the excipients with their 1:1 (w/w) binary mixtures. These same binary mixtures were turned to room temperature and analyzed by FT-IR combined with principal component analysis (PCA) to evaluate solid-state incompatibilities. The chemical incompatibilities of these samples were verified using a stability-indicating liquid chromatography (LC) method to assay for the API and evaluate the formation of degradation products. All of these methods showed incompatibilities between risperidone and the excipients magnesium stearate, lactose and cellulose microcrystalline.

  16. Optimization and in vivo toxicity evaluation of G4.5 PAMAM dendrimer-risperidone complexes.

    Directory of Open Access Journals (Sweden)

    Maria Jimena Prieto

    Full Text Available Risperidone is an approved antipsychotic drug belonging to the chemical class of benzisoxazole. This drug has low solubility in aqueous medium and poor bioavailability due to extensive first-pass metabolism and high protein binding (>90%. Since new strategies to improve efficient treatments are needed, we studied the efficiency of anionic G4.5 PAMAM dendrimers as nanocarriers for this therapeutic drug. To this end, we explored dendrimer-risperidone complexation dependence on solvent concentration, pH and molar relationship. The best dendrimer-risperidone incorporation (46 risperidone molecules per dendrimer was achieved with a mixture of chloroform:methanol 50∶50 v/v solution pH 3. In addition, to explore the possible effects of this complex, in vivo studies were carried out in the zebrafish model. Changes in the development of dopaminergic neurons and motoneurons were studied using tyrosine hydroxylase and calretinin, respectively. Physiological changes were studied through histological sections stained with hematoxylin-eosin to observe possible morphological brain changes. The most significant changes were observed when larvae were treated with free risperidone, and no changes were observed when larvae were treated with the complex.

  17. Optimization and in vivo toxicity evaluation of G4.5 PAMAM dendrimer-risperidone complexes.

    Science.gov (United States)

    Prieto, Maria Jimena; del Rio Zabala, Nahuel Eduardo; Marotta, Cristian Hernán; Carreño Gutierrez, Hector; Arévalo Arévalo, Rosario; Chiaramoni, Nadia Silvia; del Valle Alonso, Silvia

    2014-01-01

    Risperidone is an approved antipsychotic drug belonging to the chemical class of benzisoxazole. This drug has low solubility in aqueous medium and poor bioavailability due to extensive first-pass metabolism and high protein binding (>90%). Since new strategies to improve efficient treatments are needed, we studied the efficiency of anionic G4.5 PAMAM dendrimers as nanocarriers for this therapeutic drug. To this end, we explored dendrimer-risperidone complexation dependence on solvent concentration, pH and molar relationship. The best dendrimer-risperidone incorporation (46 risperidone molecules per dendrimer) was achieved with a mixture of chloroform:methanol 50∶50 v/v solution pH 3. In addition, to explore the possible effects of this complex, in vivo studies were carried out in the zebrafish model. Changes in the development of dopaminergic neurons and motoneurons were studied using tyrosine hydroxylase and calretinin, respectively. Physiological changes were studied through histological sections stained with hematoxylin-eosin to observe possible morphological brain changes. The most significant changes were observed when larvae were treated with free risperidone, and no changes were observed when larvae were treated with the complex.

  18. Review of risperidone for the treatment of pediatric and adolescent bipolar disorder and schizophrenia

    Directory of Open Access Journals (Sweden)

    Jeffrey R Bishop

    2008-03-01

    Full Text Available Jeffrey R Bishop1,2, Mani N Pavuluri21Department of Pharmacy Practice, University of Illinois at Chicago College of Pharmacy, Chicago, IL, USA; 2Department of Psychiatry, Pediatric Mood Disorders Program and Center for Cognitive Medicine, University of Illinois at Chicago College of Medicine, Chicago, IL, USAAbstract: Risperidone is a commonly used medication for the treatment of bipolar disorder and schizophrenia in children and adolescents. It has been studied as a monotherapy treatment in early onset schizophrenia and as both monotherapy and combination therapy for pediatric bipolar disorder. Studies to date indicate that risperidone is an effective treatment for positive and negative symptoms of schizophrenia and mania symptoms of bipolar disorder. In young patient populations, side effects such as weight gain, extrapyramidal side effects, and prolactin elevation require consideration when evaluating the risk benefit ratio for individual patients. Here we review published studies of risperidone for the treatment of bipolar disorder and schizophrenia in children and adolescents to provide practitioners with an overview of published data on the efficacy and safety of risperidone in these patient populations.Keywords: risperidone, bipolar disorder, schizophrenia, children, adolescents

  19. High-Dose Risperidone Induced Latent Syndrome of Inappropriate Antidiuretic Hormone Secretion With Seizure Presentation.

    Science.gov (United States)

    Lee, Yen-Feng; Tsai, Chia-Kuang; Liang, Chih-Sung

    2015-01-01

    We report a case of a patient with schizophrenia treated with high-dose risperidone, who developed syndrome of inappropriate antidiuretic hormone secretion (SIADH) with the only early symptom of tonic-clonic seizures. A 40-year-old woman with schizophrenia was treated with risperidone 2 mg/d. After the dosage was titrated to 6 mg/d, she experienced generalized seizure attacks. Laboratory screening revealed that the serum sodium level was 106 mmol/L, the urine sodium concentration was 41.2 mmol/L, and the urine osmolality was 371 mOsm/kg H2O. A diagnosis of SIADH was made, and risperidone was stopped. After infusion of hypertonic saline, the serum sodium returned to normal levels, and seizures did not recur. In this patient, SIADH advanced in a latent manner because the first and only symptom of SIADH was seizure attack. High-dose risperidone treatment is the most probable cause, and the mechanisms may be related to risperidone's high affinity for the 5-hydroxytryptamine 2A and dopamine 2 receptors. Patients with schizophrenia can display atypical features of medical illnesses. Routine physical and laboratory examinations may prevent silent disease progression.

  20. Risperidone and NAP protect cognition and normalize gene expression in a schizophrenia mouse model.

    Science.gov (United States)

    Vaisburd, Sinaya; Shemer, Zeev; Yeheskel, Adva; Giladi, Eliezer; Gozes, Illana

    2015-11-10

    Mutated disrupted in schizophrenia 1 (DISC1), a microtubule regulating protein, leads to schizophrenia and other psychiatric illnesses. It is hypothesized that microtubule stabilization may provide neuroprotection in schizophrenia. The NAP (NAPVSIPQ) sequence of activity-dependent neuroprotective protein (ADNP) contains the SxIP motif, microtubule end binding (EB) protein target, which is critical for microtubule dynamics leading to synaptic plasticity and neuroprotection. Bioinformatics prediction for FDA approved drugs mimicking SxIP-like motif which displace NAP-EB binding identified Risperidone. Risperidone or NAP effectively ameliorated object recognition deficits in the mutated DISC1 mouse model. NAP but not Risperidone, reduced anxiety in the mutated mice. Doxycycline, which blocked the expression of the mutated DISC1, did not reverse the phenotype. Transcripts of Forkhead-BOX P2 (Foxp2), a gene regulating DISC1 and associated with human ability to acquire a spoken language, were increased in the hippocampus of the DISC1 mutated mice and were significantly lowered after treatment with NAP, Risperidone, or the combination of both. Thus, the combination of NAP and standard of care Risperidone in humans may protect against language disturbances associated with negative and cognitive impairments in schizophrenia.

  1. Impact of risperidone on leptin and insulin in children and adolescents with autistic spectrum disorders.

    Science.gov (United States)

    Srisawasdi, Pornpen; Vanwong, Natchaya; Hongkaew, Yaowaluck; Puangpetch, Apichaya; Vanavanan, Somlak; Intachak, Boontarika; Ngamsamut, Nattawat; Limsila, Penkhae; Sukasem, Chonlaphat; Kroll, Martin H

    2017-08-01

    To evaluate the influence of dose and duration of risperidone treatment on cardiovascular and diabetes risk biomarkers in children and adolescents with autistic spectrum disorders (ASDs). In this cross-sectional analysis, a total of 168 ASDs patients (89% male) treated with a risperidone-based regimen for ≥12months were included. Blood samples were analyzed for glucose and lipid metabolic markers, adiponectin, leptin, prolactin, cortisol and high sensitive C-reactive protein. The mean concentrations of glucose, insulin, prolactin and leptin and HOMA-IR significantly rose with risperidone dosage (all Pleptin, prolactin and glucose concentrations and HOMA-IR show significant association with dosage. None of the markers except adiponectin showed dependence on duration of treatment. However, insulin and leptin concentrations and HOMA-IR clearly increased with increasing both dosage and duration. Dosage and duration of treatment had minimal effect on standard lipid profile and lipoprotein subclasses. Risperidone treatment disturbed glucose homeostasis and endocrine regulation (particularly leptin) in children and adolescents with ASDs, in a dose- and duration-dependent manner, being suggestive of leptin and insulin resistance mechanisms. Metabolic adverse effects, especially development of type 2 diabetes mellitus should be closely monitored, particularly in individuals receiving high doses and/or long-term risperidone treatment. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  2. Desipramine enhances the ability of risperidone to decrease alcohol intake in the Syrian golden hamster.

    Science.gov (United States)

    Gulick, Danielle; Chau, David T; Khokhar, Jibran Y; Dawson, Ree; Green, Alan I

    2014-08-30

    The atypical antipsychotic clozapine reduces alcohol drinking in patients with schizophrenia. We have proposed that clozapine׳s ability to decrease alcohol drinking relates to its weak blockade of the dopamine D2 receptor and potent blockade of the norepinephrine α-2 receptor, as well as its ability to elevate plasma and brain norepinephrine. Another atypical antipsychotic, risperidone, which is a potent blocker of both the dopamine D2 receptor and norepinephrine α-2 receptor, does not decrease alcohol drinking. In this study, we used the Syrian golden hamster to test whether the ability of risperidone to reduce alcohol drinking would be enhanced if it was used in combination with the norepinephrine reuptake inhibitor desipramine. Hamsters were given free access to water and alcohol (15% v/v) until they reached a steady drinking baseline. They were then treated daily with each drug or drug combination for 20 days. Risperidone (0.2mg/kg) only transiently decreased alcohol drinking. However, 5.0mg/kg, and possibly 1.0mg/kg, desipramine added to 0.2mg/kg risperidone appeared to produce a more substantial and relatively sustained effect than risperidone alone. Data from this study provide leads toward the development of new treatments for patients with schizophrenia and alcoholism, and also for those with alcoholism alone.

  3. Preparation of polyvinylpyrrodione microspheres by dispersion polymerization

    Institute of Scientific and Technical Information of China (English)

    Linfeng ZHAI; Tiejun SHI; Hualin WANG

    2009-01-01

    The preparation of polyvinylpyrrolidone (PVP) microspheres in ethyl acetate by dispersion polymerization with N-vinylpyrrolidone (NVP) as initial monomer, poly(N-vinylpyrrolidone-co-vinyl acetate) (P (NVP-co-VAc)) as dispersant, and 2, 2'-azobisisobutyr-onitrile(AIBN) as initiator is reported. The influences of monomer concentration, dispersant concentration and initiator concentration on the size of PVP microspheres as well as the monomer conversion were studied. The structure and properties of PVP microspheres were analyzed. The results show that the prepared PVP micro-spheres have a mean diameter of 3-4 μm. With an increase in NVP concentration, the size and the molecular weight of the PVP microspheres as well as the monomer conversion all increase. With increasing P(NVP-co-VAc) concentra-tions, the PVP molecular weight and monomer conversion both increase while the size of the microspheres becomes smaller. As the concentration of AIBN increases, the microsphere size and monomer conversion increase whereas the PVP molecular weight decreases. The PVP prepared by dispersion polymerization has a crystal structure, and its molecular weight is lower compared to that prepared by solution polymerization.

  4. Comparison of neuropsychological effects of adjunctive risperidone or quetiapine in euthymic patients with bipolar I disorder.

    Science.gov (United States)

    Kozicky, Jan-Marie; Torres, Ivan J; Bond, David J; Lam, Raymond W; Yatham, Lakshmi N

    2012-03-01

    Although associations between antipsychotic use and neuropsychological impairment in bipolar I disorder have been observed, there is a lack of studies comparing the effects of specific agents used in this population. We compared performance between patients receiving maintenance treatment with mood stabilizer monotherapy (n=15), adjunctive risperidone (n=15) or quetiapine (n=17), and a group of demographically matched healthy controls (n=28) on tests of executive function (working memory, set shifting, and inhibition) and verbal learning. Despite having a similar clinical profile, patients being treated with risperidone showed significantly impaired working memory, set-shifting, and verbal learning (Pdisorder, preliminary results indicate that addition of risperidone to a mood stabilizer has a negative impact on executive function and verbal learning, an effect not shared with quetiapine.

  5. Pregnancy exposure to olanzapine, quetiapine, risperidone, aripiprazole and risk of congenital malformations. A systematic review

    DEFF Research Database (Denmark)

    Ennis, Zandra Nymand; Damkier, Per

    2015-01-01

    To review available data on first-trimester exposure to olanzapine, quetiapine, risperidone and aripiprazole and risk of congenital malformations. We performed a systematic literature search in accordance with PRISMA guidelines identifying studies containing original data on first......-trimester exposure and pregnancy outcome with respect to congenital malformations. Cumulated data for olanzapine were 1090 first-trimester-exposed pregnancies with 38 malformations resulting in a malformation rate of 3.5%. The corresponding numbers for quetiapine, risperidone and aripiprazole were 443/16 (3.6%), 432...... of congenital malformation. Data for quetiapine and risperidone do not suggest a substantially increased risk, while the risk estimate for aripiprazole remains imprecise owing to a low amount of data....

  6. Iron Deficiency in Pediatric Patients in Long-Term Risperidone Treatment

    Science.gov (United States)

    Ziegler, Ekhard E.

    2013-01-01

    Abstract Objective Atypical antipsychotics, increasingly used in children and adolescents, modulate brain dopamine. Iron plays a critical role in dopaminergic signaling. Therefore, we explored whether body iron status is related to psychiatric symptom severity, treatment response, and tolerability following extended antipsychotic therapy. Methods Between November 2005 and August 2009, medically healthy 7–17-year-old risperidone-treated participants enrolled in a cross-sectional study examining the long-term safety of this antipsychotic. Anthropometric measurements were obtained. Psychiatric symptom severity and dietary intake were assessed. Serum ferritin, transferrin receptor, and prolactin concentrations were measured. Linear multivariable regression analysis tested the association among body iron, symptom severity, the dose of risperidone and psychostimulants, and serum prolactin concentration. Results The sample consisted of 115 patients (87% males) with a mean (±SD) age of 11.6 (±2.8) years. The majority had externalizing disorders, and they had taken risperidone for 2.4 (±1.7) years. Body iron was low, with 45% having iron depletion and 14% having iron deficiency. Iron status was inversely associated with weight gain during risperidone treatment and with interleukin-6. Body iron was neither associated with psychiatric symptom severity nor with the daily dose of risperidone and psychostimulants. It was, however, inversely associated with prolactin concentration, which was nearly 50% higher in the iron-deficient group. Conclusions Iron depletion and deficiency are prevalent in children and adolescents chronically treated with risperidone. Iron deficiency accentuates the antipsychotic-induced elevation in prolactin. Future studies should confirm this finding and investigate the potential benefit of iron supplementation in antipsychotic-treated patients. PMID:23480322

  7. Comparison the effectiveness of aripiprazole and risperidone for the treatment of acute bipolar mania

    Directory of Open Access Journals (Sweden)

    Amir Akhavan Rezayat

    2014-01-01

    Full Text Available Background: Second-generation antipsychotics, approved for the treatment of mania, are associated with adverse effects such as weight gain and metabolic disorders. Aripiprazole, a recently introduced second-generation antipsychotic, are thought to account for its low propensity for weight gain, metabolic disturbances and sedation. The purpose of this study was to investigate the effect of risperidone versus aripiprazole in the treatment of acute mania. Materials and Methods: Fifty patients with acute episodes of mania were enrolled in this study, and they were randomly assigned into a risperidone group of 24 cases and an aripiprazole group of 26 cases. In group A, aripiprazole with a dose of 5-30 mg/day and in group B, risperidone with a dose of 2-8 mg/day was given to patients. The average dose of aripiprazole was 27 mg/day, and the average dose of risperidone was 6 mg/day. The effects of each drug for the treatment of acute mania were assessed on the 1 st day of admission and on days 2, 4, 6, 8 and at weeks 2, 4 and 6 after therapy using the young mania rating scale (YMRS and at the baseline and on weeks 3 and 6 after admission using the clinical global impression (CGI scale. Results: The mean age of the group of risperidone was 34 ± 8.6 years and in a group of aripiprazole it was 34 ± 9.1 years (P = 0.83. Comparison of YMRS scores over the period of 6 weeks revealed a statistically significant difference in both groups (P < 0.0001.There was also a statistically significant difference in YMRS scores between risperidone and aripiprazole at day 8 (P = 0.026 and weeks 2 (P = 0.035 and 4 (P = 0.042. There was also a statistically significant difference in CGI-Severity scale score at weeks 3 (P = 0.003 and 6 (P = 0.000 and in CGI-Improvement scale score at weeks 3 (P = 0.005 and 6 (P = 0.002. The most common side-effect observed in both groups was headache (0%15/4 in aripiprazole vs. %16/7 in risperidone Conclusion: Aripiprazole that is readily

  8. Characterization of a Polyamine Microsphere and Its Adsorption for Protein

    Directory of Open Access Journals (Sweden)

    Huixian Wei

    2012-12-01

    Full Text Available A novel polyamine microsphere, prepared from the water-in-oil emulsion of polyethylenimine, was characterized. The investigation of scanning electron microscopy showed that the polyamine microsphere is a regular ball with a smooth surface. The diameter distribution of the microsphere is 0.37–4.29 μm. The isoelectric point of the microsphere is 10.6. The microsphere can adsorb proteins through the co-effect of electrostatic and hydrophobic interactions. Among the proteins tested, the highest value of adsorption of microsphere, 127.8 mg·g−1 microsphere, was obtained with lipase. In comparison with other proteins, the hydrophobic force is more important in promoting the adsorption of lipase. The microsphere can preferentially adsorb lipase from an even mixture of proteins. The optimum temperature and pH for the selective adsorption of lipase by the microsphere was 35 °C and pH 7.0.

  9. Organic aerogel microspheres and fabrication method therefor

    Science.gov (United States)

    Mayer, Steven T.; Kong, Fung-Ming; Pekala, Richard W.; Kaschmitter, James L.

    1996-01-01

    Organic aerogel microspheres which can be used in capacitors, batteries, thermal insulation, adsorption/filtration media, and chromatographic packings, having diameters ranging from about 1 micron to about 3 mm. The microspheres can be pyrolyzed to form carbon aerogel microspheres. This method involves stirring the aqueous organic phase in mineral oil at elevated temperature until the dispersed organic phase polymerizes and forms nonsticky gel spheres. The size of the microspheres depends on the collision rate of the liquid droplets and the reaction rate of the monomers from which the aqueous solution is formed. The collision rate is governed by the volume ratio of the aqueous solution to the mineral oil and the shear rate, while the reaction rate is governed by the chemical formulation and the curing temperature.

  10. Effect of cyamemazine on the steady-state plasma concentrations of risperidone and 9-hydroxyrisperidone: a preliminary retrospective study.

    Science.gov (United States)

    Lancelin, Frédérique; Bourcier, Elsa; Le Masson, Valérie; Lemeille, Yolande; Brovedani, Sophie; Paubel, Pascal; Piketty, Marie-Liesse

    2010-12-01

    Administration of cyamemazine, an antipsychotic drug with anxiolytic properties, together with other antipsychotic agents is common in patients with schizophrenia. This retrospective study investigated the effects of cyamemazine on the steady-state plasma concentrations of risperidone and 9-hydroxyrisperidone in 47 patients treated with 1 to 12 mg/day of risperidone. Of these 47 patients, 24 were receiving cyamemazine comedication ("cyamemazine" group) and 23 patients were treated with risperidone alone ("control" group). Plasma concentrations were measured using a high-performance liquid chromatographic method with photodiode-array ultraviolet detection. The median plasma concentration of risperidone was significantly higher in the cyamemazine group (31.5 ng/mL) than in the control group (5.0 ng/mL), whereas the 9-hydroxyrisperidone median concentration was significantly lower in the cyamemazine group (16.5 ng/mL versus 39.0 ng/mL in the control group). However, the sum of risperidone plus 9-hydroxyrisperidone (active moiety) plasma concentration was not significantly affected by cyamemazine comedication. A combination with cyamemazine resulted in an inverted metabolic ratio (risperidone/9-hydroxyrisperidone). These findings suggest that cyamemazine inhibits the 9-hydroxylation of risperidone and is probably an inhibitor of cytochrome P450 2D6 as are many other phenothiazine drugs.

  11. Risperidone: a review of its use in the treatment of irritability associated with autistic disorder in children and adolescents.

    Science.gov (United States)

    Scott, Lesley J; Dhillon, Sohita

    2007-01-01

    Risperidone (Risperdal), a psychotropic atypical antipsychotic agent, is thought to act via dopamine D(2) and serotonin (5-HT [5-hydroxytryptamine])(2A) receptor antagonism. The clinical efficacy of oral risperidone in the treatment of bipolar mania and schizophrenia in adult patients is well established. In the US, risperidone is also approved for the treatment of irritability associated with autistic disorder in children and adolescents aged 5-16 years, for the treatment of schizophrenia in adolescents aged 13-17 years and, as monotherapy, for the short-term treatment of acute manic and mixed episodes associated with bipolar I disorder in children and adolescents aged 10-17 years. Oral risperidone treatment was better than placebo treatment in reducing irritability and other behavioral symptoms associated with autistic disorder in children and adolescents in two well designed short-term trials, with these benefits maintained in those receiving risperidone for up to 6 months. The drug had a clinically manageable tolerability profile, with most adverse events being of mild to moderate intensity. There are some aspects of treatment, such as weight gain, somnolence, and hyperglycemia, that require monitoring, and the long-term safety of risperidone in children and adolescents with autistic disorder remains to be fully determined. With these issues in mind, risperidone offers a valuable emerging option for the treatment of irritability associated with autistic disorder in children and adolescents.

  12. Aripiprazole versus risperidone for treating children and adolescents with tic disorder: a randomized double blind clinical trial.

    Science.gov (United States)

    Ghanizadeh, Ahmad; Haghighi, Alireza

    2014-10-01

    There are some uncontrolled studies about the efficacy and safety of both aripiprazole and risperidone for treating tic disorder. Moreover, the efficacy of these medications has never been compared. This is the first double blind randomized clinical trial comparing the safety and efficacy of aripiprazole and risperidone for treating patients with tic disorder. Sixty children and adolescents with tic disorder were randomly allocated into one of the two groups to receive either aripiprazole or risperidone for 2 months. The primary outcome measure was the score of Yale Global Tic Severity Scale. In addition, health related quality of life and adverse events were assessed. Both aripiprazole and risperidone decreased the Yale Global Tic Severity Scale score during this trial. Moreover, both medications increased the health related quality of life score. Both aripiprazole and risperidone were tolerated well. Aripiprazole [3.22 (1.9) mg/day] decreased tic score as much as risperidone [0.6 (0.2) mg/day]. Their adverse effects and their effects on health related quality of life were comparable. However, risperidone increased the patients' social functioning more than aripiprazole in short term.

  13. Risperidone-induced weight gain is mediated through shifts in the gut microbiome and suppression of energy expenditure

    Directory of Open Access Journals (Sweden)

    Sarah M. Bahr

    2015-11-01

    Full Text Available Risperidone is a second-generation antipsychotic that causes weight gain. We hypothesized that risperidone-induced shifts in the gut microbiome are mechanistically involved in its metabolic consequences. Wild-type female C57BL/6J mice treated with risperidone (80 μg/day exhibited significant excess weight gain, due to reduced energy expenditure, which correlated with an altered gut microbiome. Fecal transplant from risperidone-treated mice caused a 16% reduction in total resting metabolic rate in naïve recipients, attributable to suppression of non-aerobic metabolism. Risperidone inhibited growth of cultured fecal bacteria grown anaerobically more than those grown aerobically. Finally, transplant of the fecal phage fraction from risperidone-treated mice was sufficient to cause excess weight gain in naïve recipients, again through reduced energy expenditure. Collectively, these data highlight a major role for the gut microbiome in weight gain following chronic use of risperidone, and specifically implicates the modulation of non-aerobic resting metabolism in this mechanism.

  14. Enhancement of the anti-immobility action of antidepressants by risperidone in the forced swimming test in mice.

    Science.gov (United States)

    Rogóż, Zofia; Kabziński, Marcin

    2011-01-01

    The aim of the present study was to examine the effect of antidepressants (ADs) belonging to different pharmacological groups and risperidone (an atypical antipsychotic drug), given separately or jointly, on immobility time in the forced swimming test in male C57BL/6J mice. The antidepressants: citalopram, fluvoxamine, sertraline, reboxetine, milnacipran (5 and 10 mg/kg), or risperidone in low doses (0.05 and 0.1 mg/kg) given alone did not change the immobility time of mice in the forced swimming test. Co-treatment with reboxetine or milnacipran (10 mg/kg) and risperidone in a lower dose of 0.05 mg/kg or with sertraline, reboxetine (5 and 10 mg/kg), citalopram, fluvoxamine, milnacipran (10 mg/kg) and risperidone in a higher dose of 0.1 mg/kg produced antidepressant-like effect in the forced swimming test. WAY100635 (a 5-HT(1A) receptor antagonist) inhibited the effects induced by co-administration of ADs and risperidone. Active behavior in the forced swimming test was not a consequence of an increased general activity, since the combined treatment with ADs and risperidone failed to enhance the locomotor activity of mice. The obtained results indicate that a low dose of risperidone enhances the activity of ADs in an animal model of depression, and that, among other mechanisms, 5-HT(1A) receptors may play a role in these effects.

  15. Hydrogen transport and storage in engineered microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Rambach, G. [Lawrence Livermore National Lab., CA (United States); Hendricks, C. [W.J. Schafer Associates, Livermore, CA (United States)

    1996-10-01

    This project is a collaboration between Lawrence Livermore National Laboratory (LLNL) and W.J. Schafer Associates (WJSA). The authors plan to experimentally verify the performance characteristics of engineered glass microspheres that are relevant to the storage and transport of hydrogen for energy applications. They will identify the specific advantages of hydrogen transport by microspheres, analyze the infrastructure implications and requirements, and experimentally measure their performance characteristics in realistic, bulk storage situations.

  16. A Comparison of Risperidone and Buspirone for Treatment of Behavior Disorders in Children with Phenylketonuria

    Directory of Open Access Journals (Sweden)

    Afshin FAYYAZI

    2014-12-01

    Full Text Available How to Cite This Article: Fayyazi A, Salari E, Khajeh A, Ghajarpour A. A Comparison of Risperidone and Buspirone for Treatment ofBehavior Disorders in Children with Phenylketonuria. Iran J Child Neurol. 2014 Autumn; 8(4:33-38.AbstractObjectiveMany patients with late-diagnosed phenylketonuria (PKU suffer from severe behavior problems. This study compares the effects of buspirone and risperidone on reducing behavior disorders in these patients.Materials & MethodsIn this crossover clinical trial study, patients with severe behavior disorders after medical examination were randomly divided into two groups of two 8-week crossover treatments with risperidone or buspirone. Patient behavioral disorders before and after treatment by each drug was rated by parents on the Nisonger Child Behavior Rating Form (NCBRF, and after treatment by each drug, were assessed by a physician through clinical global impression (CGI.ResultsThirteen patients were able to complete the therapy period with these two medications.The most common psychiatric diagnoses were intellectual disability accompanied by pervasive developmental disorder NOS, and intellectual disability accompanied by autistic disorder. Risperidone was significantly effective in reducing the NCBRF subscales of hyperactivity disruptive/ stereotypic, and conduct problems. Treatment by buspirone only significantly decreased the severity of hyperactivity, but other behavior aspects showed no significant differences. Assessment of the severity of behavior disorder after treatment by risperidone and buspirone showed significant differences in reducing hyperactivity and masochistic/stereotype.ConclusionAlthough buspirone is effective in controlling hyperactivity in patients with PKU, it has no preference over risperidone. Therefore, it is recommended as an alternative to risperidone.ReferencesSmith I, Nowles JK. Behaviour in early treated phenylketonuria: a systematic review. Eur J Pediatr 2000;159:89-93.Targum SD

  17. 奥美拉唑对利培酮和9-羟利培酮血药浓度影响的研究%Influence study of omeprazole on blood drug concentration of risperidone and 9-hydroxy risperidone

    Institute of Scientific and Technical Information of China (English)

    巫艳芬; 王玉梅; 陈宝燕

    2014-01-01

    目的:观察奥美拉唑对利培酮和9-羟利培酮血药浓度的影响。方法20例精神分裂症合并胃溃疡患者,给予利培酮联合奥美拉唑治疗1周。检测奥美拉唑治疗后利培酮以及9-羟利培酮血药浓度。结果未使用奥美拉唑前,利培酮与9-羟利培酮血药浓度为(29.25±7.82)μg/L;使用奥美拉唑后,利培酮与9-羟利培酮血药浓度为(37.15±11.68)μg/L,差异有统计学意义(P<0.05)。结论奥美拉唑能够提高利培酮与9-羟利培酮血药浓度,因此,临床上治疗精神分裂症合并胃溃疡患者,给予奥美拉唑联合利培酮治疗时,应该监测患者利培酮与9-羟利培酮血药浓度,及时对药物剂量进行调整。%Objective To observe the influence of omeprazole on blood drug concentration of risperidone and 9-hydroxy risperidone. Methods A total of 20 schizophrenia with gastric ulcer cases were treated by risperidone combined with omeprazole for 1 week. Detections of blood drug concentration of risperidone and 9-hydroxy risperidone were made after the omeprazole treatment. Results Before application of omeprazole, blood drug concentration of risperidone and 9-hydroxy risperidone was (29.25±7.82)μg/L. After using omeprazole, blood drug concentration of risperidone and 9-hydroxy risperidone was (37.15±11.68) μg/L. The difference had statistical significance (P<0.05). Conclusion Omeprazole can increase the blood drug concentration of risperidone and 9-hydroxy risperidone, which should be monitored in the risperidone combined with omeprazole treatment of schizophrenia with gastric ulcer, and timely adjustment of drug dose is necessary.

  18. Coacervate microspheres as carriers of recombinant adenoviruses.

    Science.gov (United States)

    Kalyanasundaram, S; Feinstein, S; Nicholson, J P; Leong, K W; Garver, R I

    1999-01-01

    The therapeutic utility of recombinant adenoviruses (rAds) is limited in part by difficulties in directing the viruses to specific sites and by the requirement for bolus administration, both of which limit the efficiency of target tissue infection. As a first step toward overcoming these limitations, rAds were encapsulated in coacervate microspheres comprised of gelatin and alginate followed by stabilization with calcium ions. Ultrastructural evaluation showed that the microspheres formed in this manner were 0.8-10 microM in diameter, with viruses evenly distributed. The microspheres achieved a sustained release of adenovirus with a nominal loss of bioactivity. The pattern of release and the total amount of virus released was modified by changes in microsphere formulation. Administration of the adenovirus-containing microspheres to human tumor nodules engrafted in mice showed that the viral transgene was transferred to the tumor cells. It is concluded that coacervate microspheres can be used to encapsulate bioactive rAd and release it in a time-dependent manner.

  19. Demonstration of Microsphere Insulation in Cryogenic Vessels

    Science.gov (United States)

    Baumgartner, R. G.; Myers, E. A.; Fesmire, J. E.; Morris, D. L.; Sokalski, E. R.

    2006-04-01

    While microspheres have been recognized as a legitimate insulation material for decades, actual use in full-scale cryogenic storage tanks has not been demonstrated until now. The performance and life-cycle-cost advantages previously predicted have now been proven. Most bulk cryogenic storage tanks are insulated with either multilayer insulation (MLI) or perlite. Microsphere insulation, consisting of hollow glass bubbles, combines in a single material the desirable properties that other insulations only have individually. The material has high crush strength, low density, is noncombustible, and performs well in soft vacuum. These properties were proven during recent field testing of two 22,700-L (6,000-gallon) liquid nitrogen tanks, one insulated with microsphere insulation and the other with perlite. Normal evaporation rates (NER) for both tanks were monitored with precision test equipment and insulation levels within the tanks were observed through view ports as an indication of insulation compaction. Specific industrial applications were evaluated based on the test results and beneficial properties of microsphere insulation. Over-the-road trailers previously insulated with perlite will benefit not only from the reduced heat leak, but also the reduced mass of microsphere insulation. Economic assessments for microsphere-insulated cryogenic vessels including life-cycle cost are also presented.

  20. Evaluation of glibenclamide microspheres for sustained release

    Directory of Open Access Journals (Sweden)

    Kambham Venkateswarlu

    2017-04-01

    Full Text Available Context: Sustained release drug delivery systems are more preferred than the conventional drug delivery systems due to its enhanced bioavailability and patient compliance. Earlier studies reported on glibenclamide (GBCM were not clear and hence, the step has been taken to explore the sustained release drug delivery system of GBCM. Aims: To evaluate the sustained release microspheres obtained of GBCM. Methods: Microspheres were prepared by ionic gelation method using the polymers like Eudragit RS 100 and xanthan gum. Polymers can sustain the drug release from microspheres. The prepared microspheres were subjected to micromeritic studies like Carr’s index, Hausner’s ratio and angle of repose. Results: Micromeritic studies confirmed that the microspheres possessing acceptable flow properties. It was observed from the in vitro release studies, formulations F8 and F9 showed sustained drug release for desired time of 12 h and when compared to F9, formulation F8 showed maximum drug release for 12 h. Conclusions: Results confirmed the formulation F8 consist of the polymers such as Eudragit RS 100 about 150 mg and xanthan gum about 100 mg showed desired sustained release of 12 h with 96.07% and kinetic studies confirmed that the release from microspheres followed non-Fickian diffusion mechanism. Due to its sustained release property, it could enhance the bioavailability of drug thereby improves the patient compliance and expect better treatment than conventional dosage forms.

  1. The advanced stages of stellar evolution: impact of mass loss, rotation, and link with B[e] stars

    CERN Document Server

    Georgy, Cyril; Ekström, Sylvia; Meynet, Georges

    2016-01-01

    In this paper, we discuss some consequences of rotation and mass loss on the evolved stages of massive star evolution. The physical reasons of the time evolution of the surface velocity are explained, and then we show how the late-time evolution of massive stars are impacted in combination with the effects of mass loss. The most interesting result is that in some cases, a massive star can have a blue-red-blue evolution, opening the possibility that Blue Supergiants are composed by two distinct populations of stars: one just leaving the main sequence and crossing the HRD for the first time, and the other one evolving back to the blue side of the HRD after a Red Supergiant phase. We discuss a few possible observational tests that can allow to distinguish these two populations, and how supergiant B[e] stars fit in this context.

  2. Probing Gas and Dust around B[e] Stars at the Highest Angular Resolution: A Decade of Interferometric Studies

    Science.gov (United States)

    Meilland, A.

    2017-02-01

    Long-baseline interferometry is the one and only technique offering the sub-milliarcsecond resolution needed to spatially resolve the close environment of stars. Since the construction of modern facilities such as the Very Large Telescope Interferometer (VLTI) in Chile, and the Center for High Resolution Array (CHARA) in California, it became a key technique to probe massive stars and their often complex circumstellar environments. The more recent generation of instruments even combines the power of interferometry and spectroscopy allowing to put more constraints on chemical, physical, and dynamical properties of circumstellar gas and dust. Here I briefly present the technique and the current generation of instruments, I review the main results obtained in the last decade on B[e] stars, and, I present the upcoming second generation of instruments at VLTI and the current plan to upgrade CHARA.

  3. POE/PLGA composite microspheres: formation and in vitro behavior of double walled microspheres.

    Science.gov (United States)

    Yang, Yi-Yan; Shi, Meng; Goh, Suat-Hong; Moochhala, Shabbir M; Ng, Steve; Heller, Jorge

    2003-03-07

    The poly(ortho ester) (POE) and poly(D,L-lactide-co-glycolide) 50:50 (PLGA) composite microspheres were fabricated by a water-in-oil-in-water (w/o/w) double emulsion process. The morphology of the composite microspheres varied depending on POE content. When the POE content was 50, 60 or 70% in weight, the double walled microspheres with a dense core of POE and a porous shell of PLGA were formed. The formation of the double walled POE/PLGA microspheres was analysed. Their in vitro degradation behavior was characterized by scanning electron microscopy, gel permeation chromatography, Fourier-transform infrared microscopy and nuclear magnetic resonance spectroscopy (NMR). It was found that compared to the neat POE or PLGA microspheres, distinct degradation mechanism was achieved in the double walled POE/PLGA microspheres system. The degradation of the POE core was accelerated due to the acidic microenvironment produced by the hydrolysis of the outer PLGA layer. The formation of hollow microspheres became pronounced after the first week in vitro. 1H NMR spectra showed that the POE core was completely degraded after 4 weeks. On the other hand, the outer PLGA layer experienced slightly retarded degradation after the POE core disappeared. PLGA in the double walled microspheres kept more than 32% of its initial molecular weight over a period of 7 weeks.

  4. PLGA/alginate composite microspheres for hydrophilic protein delivery

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Peng [Department of Anatomy and Cell Biology, University of Saskatchewan, S7N5E5 (Canada); Division of Biomedical Engineering, University of Saskatchewan, S7N5A9 (Canada); Chen, X.B. [Department of Mechanical Engineering, University of Saskatchewan, S7N5A9 (Canada); Division of Biomedical Engineering, University of Saskatchewan, S7N5A9 (Canada); Schreyer, David J., E-mail: david.schreyer@usask.ca [Department of Anatomy and Cell Biology, University of Saskatchewan, S7N5E5 (Canada); Division of Biomedical Engineering, University of Saskatchewan, S7N5A9 (Canada)

    2015-11-01

    Poly(lactic-co-glycolic acid) (PLGA) microspheres and PLGA/alginate composite microspheres were prepared by a novel double emulsion and solvent evaporation technique and loaded with bovine serum albumin (BSA) or rabbit anti-laminin antibody protein. The addition of alginate and the use of a surfactant during microsphere preparation increased the encapsulation efficiency and reduced the initial burst release of hydrophilic BSA. Confocal laser scanning microcopy (CLSM) of BSA-loaded PLGA/alginate composite microspheres showed that PLGA, alginate, and BSA were distributed throughout the depths of microspheres; no core/shell structure was observed. Scanning electron microscopy revealed that PLGA microspheres erode and degrade more quickly than PLGA/alginate composite microspheres. When loaded with anti-laminin antibody, the function of released antibody was well preserved in both PLGA and PLGA/alginate composite microspheres. The biocompatibility of PLGA and PLGA/alginate microspheres were examined using four types of cultured cell lines, representing different tissue types. Cell survival was variably affected by the inclusion of alginate in composite microspheres, possibly due to the sensitivity of different cell types to excess calcium that may be released from the calcium cross-linked alginate. - Highlights: • A double emulsion technique is used to prepare protein-loaded PLGA or PLGA/alginate microspheres. • PLGA, alginate and protein are distributed evenly within microsphere structure. • Addition of alginate improves loading efficiency and slows degradation and protein release. • PLGA/alginate microspheres have favorable biocompatibility.

  5. A pharmaco-economic analysis of patients with schizophrenia switching to generic risperidone involving a possible compliance loss

    Directory of Open Access Journals (Sweden)

    Möller Hans-Jürgen

    2009-02-01

    Full Text Available Abstract Background As schizophrenia patients are typically suspicious of, or are hostile to changes they may be reluctant to accept generic substitution, possibly affecting compliance. This may counteract drug costs savings due to less symptom control and increased hospitalization risk. Although compliance losses following generic substitution have not been quantified so far, one can estimate the possible health-economic consequences. The current study aims to do so by considering the case of risperidone in Germany. Methods An existing DES model was adapted to compare staying on branded risperidone with generic substitution. Differences include the probability of non-compliance and medication costs. Incremental probability of non-compliance after generic substitution was varied between 2.5% and 10%, while generic medication costs were assumed to be 40% lower. Effect of medication price was assessed as well as the effect of applying compliance losses to all treatment settings. The probability of staying on branded risperidone being cost-effective was calculated for various outcomes of a hypothetical study that would investigate non-compliance following generic substitution of risperidone. Results If the incremental probability of non-compliance after generic substitution is 2.5%, 5.0%, 7.5% and 10% respectively, incremental effects of staying on branded risperidone are 0.004, 0.007, 0.011 and 0.015 Quality Adjusted Life Years (QALYs. Incremental costs are €757, €343, -€123 and -€554 respectively. Benefits of staying on branded risperidone include improved symptom control and fewer hospitalizations. If generic substitution results in a 5.2% higher probability of non-compliance, the model predicts staying on branded risperidone to be cost-effective (NICE threshold of ₤30,000 per QALY gained. Compliance losses of more than 6.9% makes branded risperidone the dominant alternative. Results are sensitive to the locations at which compliance

  6. Dietary Status and Impact of Risperidone on Nutritional Balance in Children with Autism: A Pilot Study

    Science.gov (United States)

    Lindsay, Ronald L.; Arnold, L. Eugene; Aman, Michael G.; Vitiello, Benedetto; Posey, David J.; McDougle, Christopher J.; Scahill, Lawrence; Pachler, Maryellen; McCracken, James T.; Tierney, Elaine; Bozzolo, Dawn

    2006-01-01

    Background: Risperidone may be effective in improving tantrums, aggression, or self-injurious behaviour in children with autism, but often leads to weight gain. Method: Using a quantitative Food Frequency Questionnaire (FFQ), we prospectively examined the nutritional intake of 20 children with autism participating in a randomised…

  7. Risperidone versus olanzapine in the acute treatment of Persistent Delusional Disorder: A retrospective analysis.

    Science.gov (United States)

    Kulkarni, Karishma; Arasappa, Rashmi; Prasad M, Krishna; Zutshi, Amit; Chand, Prabhat K; Murthy, Pratima; Philip, Mariamma; Muralidharan, Kesavan

    2017-07-01

    There is a dearth of prospective trials studying treatment response in Persistent Delusional Disorder (PDD) to guide clinical practice. Available retrospective data indicate good response to second-generation antipsychotics (SGAs). We selected the data of patients prescribed either olanzapine or risperidone from a retrospective chart review of PDD (n=455) at our centre. We compared the two groups olanzapine (n =86) versus risperidone (n =280) on dose, drug adherence, response and adverse effects. The two groups were comparable on socio-demographic and clinical characteristics of PDD. There was no statistically significant difference between the two groups on adherence (>80%) and response to treatment (>52% good response). Olanzapine was effective at lower mean chlorpromazine equivalents than risperidone. Logistic regression analysis identified shorter mean duration of illness, good adherence and absence of substance dependence as predictors of good response to both drugs. Our study indicates that acute PDD responds well to treatment with both risperidone and olanzapine, provided adherence can be ensured. In the absence of specific treatment guidelines and randomized controlled trials for PDD, our analysis reaffirms the efficacy of SGAs. Copyright © 2017. Published by Elsevier B.V.

  8. Risperidone treatment for ADHD in children and adolescents with bipolar disorder

    Directory of Open Access Journals (Sweden)

    Joseph Biederman

    2008-03-01

    Full Text Available Joseph Biederman, Paul Hammerness, Robert Doyle, Gagan Joshi, Megan Aleardi, Eric MickPediatric Psychopharmacology Research Department, Massachusetts General Hospital, Boston, MA, USAObjective: Children and adolescents with bipolar disorder are also at high risk of having comorbid attention-deficit hyperactivity disorder (ADHD. The objective of this study was to estimate improvement in ADHD symptoms in children with bipolar disorder.Methods: This was an open-label, study of risperidone monotherapy for the treatment of pediatric bipolar disorder. Thirty-one children and adolescents 4–15 years of age (7.2 ± 2.8 years of both sexes (71%, N = 22 male with pediatric bipolar disorder (YMRS score = 32.9 ± 8.8 and ADHD (ADHD-RS score = 37.9 ± 8.9 were included in these analyses.Results: Improvement in ADHD symptoms was contingent on improvement in manic symptoms. Although both hyperactive/impulsive (−7.5 ± 5.5.6, p < 0.05 and inattentive (−6.8 ± 5.0, p < 0.05 ADHD symptoms were significantly improved with risperidone, improvement was modest, and only 29% of subjects (N = 6 showed a 30% reduction in ADHD rating scale scores and had a CGI-I ≤ 2.Conclusions: These results suggest that that treatment with risperidone is associated with tangible but generally modest improvement of symptoms of ADHD in children with bipolar disorder.Keywords: ADHD, bipolar disorder, children, risperidone

  9. Neuropsychological effects of risperidone in children with pervasive developmental disorders : A blinded discontinuation study

    NARCIS (Netherlands)

    Troost, Pieter W.; Althaus, Monika; Lahuis, Bertine E.; Buitelaar, Jan K.; Minderaa, Ruud B.; Hoekstra, Pieter J.

    2006-01-01

    Objective: Little is known about the neuropsychological effects of risperidone in children with pervasive developmental disorders. Method: Twenty-four children (aged 5-17 years) with pervasive developmental disorders and co-morbid disruptive behavior who responded favorably to open-label treatment

  10. Tic Reduction with Risperidone Versus Pimozide in a Randomized, Double-Blind, Crossover Trial

    Science.gov (United States)

    Gilbert, Donald L.; Batterson, J. Robert; Sethuraman, Gopalan; Sallee, Floyd R.

    2004-01-01

    Objective: To compare the tic suppression, electrocardiogram (ECG) changes, weight gain, and side effect profiles of pimozide versus risperidone in children and adolescents with tic disorders. Method: This was a randomized, double-blind, crossover (evaluable patient analysis) study. Nineteen children aged 7 to 17 years with Tourette's or chronic…

  11. Switching to quetiapine for risperidone-induced amenorrhea: Report of two cases

    Directory of Open Access Journals (Sweden)

    P K Pardal

    2010-01-01

    Full Text Available Almost all the antipsychotics can cause hyperprolactinemia-related side-effects like amenorrhea. Quetiapine has been reported to have minimal propensity to cause hyperprolactinemia. We report here two cases of risperidone-induced amenorrhea, who resumed their normal cycle on switching over the medication to quetiapine.

  12. Potentiating effect of fluphenazine decanoate and risperidone on development of neuroleptic malignant syndrome.

    Science.gov (United States)

    Liu, Pang-Yen; Wu, Pei-Chuan; Chen, Chun-Yen; Chen, Yi-Chyan

    2011-01-01

    We present the case of a woman with paranoid schizophrenia who was receiving oral risperidone. She developed neuroleptic malignant syndrome (NMS) following the addition of depot fluphenazine for the treatment of refractory delusions. NMS subsided and psychotic features were controlled after both antipsychotics were discontinued and the patient was treated instead with olanzapine.

  13. Paediatric European Risperidone Studies (PERS) : context, rationale, objectives, strategy, and challenges

    NARCIS (Netherlands)

    Glennon, Jeffrey; Purper-Ouakil, Diane; Bakker, Mireille; Zuddas, Alessandro; Hoekstra, Pieter; Schulze, Ulrike; Castro-Fornieles, Josefina; Santosh, Paramala J.; Arango, Celso; Koelch, Michael; Coghill, David; Flamarique, Itziar; Penzol, Maria J.; Wan, Mandy; Murray, Macey; Wong, Ian C. K.; Danckaerts, Marina; Bonnot, Olivier; Falissard, Bruno; Masi, Gabriele; Fegart, Joerg M.; Vicari, Stefano; Carucci, Sara; Dittmann, Ralf W.; Buitelaar, Jan K.

    2014-01-01

    In children and adolescents with conduct disorder (CD), pharmacotherapy is considered when non-pharmacological interventions do not improve symptoms and functional impairment. Risperidone, a second-generation antipsychotic is increasingly prescribed off-label in this indication, but its efficacy and

  14. Spontaneous seizures after ECT in a patient medicated with bupropion, sertraline and risperidone

    Directory of Open Access Journals (Sweden)

    Orlando von Doellinger

    Full Text Available Abstract Objective: To report a case of post-electroconvulsive therapy spontaneous seizures in a patient medicated with sertraline, bupropion and risperidone. Case description: A 53-year-old woman with recurrent major depression was admitted to our psychiatry department for a major depressive episode of 6 weeks' duration, with psychotic symptoms. She was already on 200 mg/day of sertraline and 2 mg/day of risperidone. After 8 weeks on 200 mg/day of sertraline, 4 mg/day of risperidone and slow release bupropion (titrated to 300 mg/day, with no objective improvements, the decision was taken to initiate a course of 8-10 electroconvulsive therapy (ECT sessions. Two days after the first treatment, three generalized tonic-clonic seizures occurred within 6 hours. Phenytoin and sodium valproate were added to the patient's daily medication and no further spontaneous seizures were observed. After neurologic assessment and discussion of the case, phenytoin and bupropion were withdrawn at once (two days after the spontaneous seizures and the decision was taken to resume the ECT treatment. No further spontaneous seizures occurred and, at discharge, the patient exhibited significant improvements and was free from major depressive symptoms. Comments: This report illustrates a case of post-ECT spontaneous seizures that might have been due to a specific pharmacological etiological pathway, namely, bupropion's proconvulsive properties, although both sertraline and risperidone also lower the convulsive threshold.

  15. Paediatric European Risperidone Studies (PERS): context, rationale, objectives, strategy, and challenges

    NARCIS (Netherlands)

    Glennon, J.C.; Purper-Ouakil, D.; Bakker, M; Zuddas, A.; Hoekstra, P.; Schulze, U.; Castro-Fornieles, J.; Santosh, P.J.; Arango, C.; Kolch, M.; Coghill, D.; Flamarique, I.; Penzol, M.J.; Wan, M.; Murray, M.; Wong, I.C.; Danckaerts, M.; Bonnot, O.; Falissard, B.; Masi, G.; Fegert, J.M.; Vicari, S.; Carucci, S.; Dittmann, R.W.; Buitelaar, J.

    2014-01-01

    In children and adolescents with conduct disorder (CD), pharmacotherapy is considered when non-pharmacological interventions do not improve symptoms and functional impairment. Risperidone, a second-generation antipsychotic is increasingly prescribed off-label in this indication, but its efficacy and

  16. Paediatric European Risperidone Studies (PERS) : context, rationale, objectives, strategy, and challenges

    NARCIS (Netherlands)

    Glennon, Jeffrey; Purper-Ouakil, Diane; Bakker, Mireille; Zuddas, Alessandro; Hoekstra, Pieter; Schulze, Ulrike; Castro-Fornieles, Josefina; Santosh, Paramala J.; Arango, Celso; Koelch, Michael; Coghill, David; Flamarique, Itziar; Penzol, Maria J.; Wan, Mandy; Murray, Macey; Wong, Ian C. K.; Danckaerts, Marina; Bonnot, Olivier; Falissard, Bruno; Masi, Gabriele; Fegart, Joerg M.; Vicari, Stefano; Carucci, Sara; Dittmann, Ralf W.; Buitelaar, Jan K.

    2014-01-01

    In children and adolescents with conduct disorder (CD), pharmacotherapy is considered when non-pharmacological interventions do not improve symptoms and functional impairment. Risperidone, a second-generation antipsychotic is increasingly prescribed off-label in this indication, but its efficacy and

  17. Stability Indicating HPLC Determination of Risperidone in Bulk Drug and Pharmaceutical Formulations

    Directory of Open Access Journals (Sweden)

    Zarna R. Dedania

    2011-01-01

    Full Text Available The objective of the current study was to develop a validated stability-indicating assay method (SIAM for risperidone after subjecting it to forced decomposition under hydrolysis, oxidation, photolysis, and thermal stress conditions. The liquid chromatographic separation was achieved isocratically on a symmetry C18 column (5 μm size, 250 mm × 4.6 mm i.d. using a mobile phase containing methanol: acetonitrile (80 : 20, v/v at a flow rate of 1 mL/min and UV detection at 280 nm. Retention time of risperidone was found to be 3.35±0.01. The method was linear over the concentration range of 10–60 μg/mL(2=0.998 with a limit of detection and quantitation of 1.79 and 5.44 μg/mL, respectively. The method has the requisite accuracy, specificity, sensitivity, and precision to assay risperidone in bulk form and pharmaceutical dosage forms. Degradation products resulting from the stress studies did not interfere with the detection of Risperidone, and the assay is thus stability indicating.

  18. Long-term effects of risperidone in children with autism spectrum disorders : A placebo discontinuation study

    NARCIS (Netherlands)

    Troost, PW; Lahuis, BE; Steenhuis, MP; Ketelaars, CEJ; Buitelaar, JK; Van Engeland, H; Scahill, L; Minderaa, RB; Hoekstra, PJ

    2005-01-01

    Objective: The short-term benefit of risperidone in ameliorating severe disruptive behavior in pediatric patients with autism spectrum disorders is well established; however, only one placebo-controlled, long-term study of efficacy is available. Method: Thirty-six children with an autism spectrum di

  19. Clinical and pharmacokinetic evaluation of risperidone for the management of autism spectrum disorder

    NARCIS (Netherlands)

    Dinnissen, Mariken; Dietrich, Andrea; van den Hoofdakker, Barbara J.; Hoekstra, Pieter J.

    2015-01-01

    Introduction: Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is often accompanied by psychiatric comorbidity. Although there is no medication currently available to treat the core symptoms of ASD, risperidone was the first drug to be approved for use in ASD and is still the bes

  20. Antipsychotic-induced extrapyramidal syndromes - Risperidone compared with low- and high-potency conventional antipsychotic drugs

    NARCIS (Netherlands)

    Schillevoort, [No Value; de Boer, A; Herings, RMC; Roos, RAC; Jansen, PAF; Leufkens, HGM

    2001-01-01

    Aim: To compare the risk of extrapyramidal syndromes (EPS) between patients using risperidone and those using low-potency conventional antipsychotic drugs (APDs) in outpatient clinical practice, as measured by the use of anticholinergic medication. We tried to replicate results from previous clinica

  1. Neuropsychological effects of risperidone in children with pervasive developmental disorders: a blinded discontinuation study.

    NARCIS (Netherlands)

    Troost, P.W.; Althaus, M.; Lahuis, B.E.; Buitelaar, J.K.; Minderaa, R.B.; Hoekstra, P.J.

    2006-01-01

    OBJECTIVE: Little is known about the neuropsychological effects of risperidone in children with pervasive developmental disorders. METHOD: Twenty-four children (aged 5-17 years) with pervasive developmental disorders and co-morbid disruptive behavior who responded favorably to open-label treatment w

  2. Celecoxib and omega-3 fatty acids alone and in combination with risperidone affect the behavior and brain biochemistry in amphetamine-induced model of schizophrenia.

    Science.gov (United States)

    El-Sayed El-Sisi, Alaa; Sokkar, Samia Salem; El-Sayed El-Sayad, Magda; Sayed Ramadan, Ehab; Osman, Enass Yossef

    2016-08-01

    The implications of oxidative stress and neuro-inflammation in the pathogenesis of schizophrenia have been elucidated. Despite their effectiveness against positive symptoms of schizophrenia, antipsychotics have limited effectiveness against negative and cognitive symptoms and are associated with remarkable adverse effects. The use of celecoxib or omega-3 in schizophrenia may have beneficial effects. This study aimed to evaluate the possible efficacies of celecoxib, omega-3 or the combination of celecoxib+risperidone and omega-3+ risperidone compared to risperidone on the behavior and brain biochemistry in rats. In the present study, an amphetamine-induced model of schizophrenia in adult male rats was used to evaluate the effects of celecoxib, omega-3, celecoxib+risperidone and omega-3+ risperidone on the behavior of animals and on brain lipid peroxidation or tumor necrosis factor-alpha. In the water maze task, celecoxib, omega-3, celecoxib+risperidone, omega-3+ risperidone significantly decreased the latency time compared to amphetamine-treated group. Celecoxib, omega-3, celecoxib+risperidone, omega-3+risperidone also significantly reversed the decreased spontaneous alternation induced by amphetamine in the Y-maze task. In the social interaction task, groups treated with celecoxib, omega-3, celecoxib+risperidone, omega-3+ risperidone spent less time to recognize foreign animals than animals in the amphetamine-treated group. Increased brain MDA and TNF-α levels due to amphetamine were significantly reduced in groups treated with celecoxib+risperidone or omega-3+ risperidone. The present findings showed that celecoxib or omega-3 can attenuate amphetamine- induced behavioral impairment and these effects may be associated with their ability to decrease lipid peroxidation and cytokine release. Celecoxib or omega-3 may be promising candidates as adjuvant therapy for schizophrenia.

  3. Hierarchical bismuth phosphate microspheres with high photocatalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Lizhai; Wei, Tian; Lin, Nan; Yu, Haiyun [Anhui University of Technology, Ma' anshan (China). Key Laboratory of Materials Science and Processing of Anhui Province

    2016-05-15

    Hierarchical bismuth phosphate microspheres have been prepared by a simple hydrothermal process with polyvinyl pyrrolidone. Scanning electron microscopy observations show that the hierarchical bismuth phosphate microspheres consist of nanosheets with a thickness of about 30 nm. The diameter of the microspheres is about 1 - 3 μm. X-ray diffraction analysis shows that the microspheres are comprised of triclinic Bi{sub 23}P{sub 4}O{sub 44.5} phase. The formation of the hierarchical microspheres depends on polyvinyl pyrrolidone concentration, hydrothermal temperature and reaction time. Gentian violet acts as the pollutant model for investigating the photocatalytic activity of the hierarchical bismuth phosphate microspheres under ultraviolet-visible light irradiation. Irradiation time, dosage of the hierarchical microspheres and initial gentian violet concentration on the photocatalytic efficiency are also discussed. The hierarchical bismuth phosphate microspheres show good photocatalytic performance for gentian violet removal in aqueous solution.

  4. Deltoid injections of risperidone long-acting injectable in patients with schizophrenia.

    Science.gov (United States)

    Quiroz, Jorge A; Rusch, Sarah; Thyssen, An; Palumbo, Joseph M; Kushner, Stuart

    2011-06-01

    Risperidone long-acting injectable was previously approved for treatment of schizophrenia as biweekly injections in the gluteal muscle only. We present data on local injection-site tolerability and safety of risperidone long-acting injectable and comparability of systemic exposure of deltoid versus gluteal injections. Risperidone long-acting injectable was administered in an open-label, single-dose, two-way crossover study, with patients randomized to receive either 25mg gluteal/37.5mg deltoid crossover in two treatment periods or 50mg gluteal/50mg deltoid injections crossover; each treatment period was separated by an 85-day observation period (Study 1) and an open-label, multiple-dose study (4 sequential 37.5mg or 50mg deltoid injections every 2 weeks) (Study 2). The pharmacokinetic results from both the studies have already been published. In Study 1 (n=170), the majority of patients had no local injection-site findings, based on investigator and patient-rated evaluations. In Study 2 (n=53), seven of the 51 patients who received at least two deltoid injections discontinued (primary endpoint). However, none of the discontinuations were due to injection-site related reasons. The 90-percent upper confidence limit of the true proportion of injection-site issue withdrawals was 5.7 percent. No moderate or severe injection-site reactions were reported. Intramuscular injections via the deltoid and gluteal sites are equivalent routes of administration of risperidone long-acting injectable with respect to local injection-site tolerability. The overall safety and tolerability profile of risperidone long-acting injectable was comparable when administered as an intramuscular injection in the deltoid (37.5mg and 50mg) and gluteal (25mg and 50mg) sites.

  5. Risperidone significantly inhibits interferon-gamma-induced microglial activation in vitro.

    Science.gov (United States)

    Kato, Takahiro; Monji, Akira; Hashioka, Sadayuki; Kanba, Shigenobu

    2007-05-01

    Microglia has recently been regarded to be a mediator of neuroinflammation via the release of proinflammatory cytokines, nitric oxide (NO) and reactive oxygen species (ROS) in the central nervous system (CNS). Microglia has thus been reported to play an important role in the pathology of neurodegenerative disease, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The pathological mechanisms of schizophrenia remain unclear while some recent neuroimaging studies suggest even schizophrenia may be a kind of neurodegenerative disease. Risperidone has been reported to decrease the reduction of MRI volume during the clinical course of schizophrenia. Many recent studies have demonstrated that immunological mechanisms via such as interferon (IFN)-gamma and cytokines might be relevant to the pathophysiology of schizophrenia. In the present study, we thus investigated the effects of risperidone on the generation of nitric oxide, inducible NO synthase (iNOS) expression and inflammatory cytokines: interleukin (IL)-1beta, IL-6 and tumor necrosis factor (TNF)-alpha by IFN-gamma-activated microglia by using Griess assay, Western blotting and ELISA, respectively. In comparison with haloperidol, risperidone significantly inhibited the production of NO and proinflammatory cytokines by activated microglia. The iNOS levels of risperidone-treated cells were much lower than those of the haloperidol-treated cells. Antipsychotics, especially risperidone may have an anti-inflammatory effect via the inhibition of microglial activation, which is not only directly toxic to neurons but also has an inhibitory effect on neurogenesis and oligodendrogenesis, both of which have been reported to play a crucial role in the pathology of schizophrenia.

  6. Comparative study on clinically latent aggressiveness inoutpatients with schizophrenia treated with classical antipsychotics and with risperidone

    Directory of Open Access Journals (Sweden)

    Konstantinos Tsirigotis

    2014-03-01

    Full Text Available Objective: The use of neuroleptics causes not only regression of psychotic symptoms; neuroleptics affect also the patients’ mental state which is changing not only due to medications effects but also secondarily, as a result of regression of psychotic symptoms. The aim of this study was evaluation of subjectively felt “silent” (clinically latent hostility and aggressiveness in patients with paranoid schizophrenia treated with typical neuroleptics and risperidone. Material and methods: Sixty patients (30 patients treated with typical neuroleptics and the other 30 – with risperidone were examined with the Polish version of the following tools: Minnesota Multiphasic Personality Inventory (MMPI, Adjective Check List (ACL and Stern Activities Index (SAI. Results: The statistical analysis of the obtained results yielded many statistically significant differences within the intensity of hostility and aggressiveness in the examined groups. Conclusions: The results of this study showed a higher severity of psychological and personality problems in patients treated with typical neuroleptics, as compared to those treated with risperidone. In patients with paranoid schizophrenia treated with risperidone a lower severity of psychopathological, especially schizophrenic and paranoid, symptoms and lower hostility and aggressiveness were found. Considering that risperidone improves verbal functions, it can be assumed that this entails an improvement in the patients’ communicative competences, thereby improving also their interpersonal relationships. The results of this study indicate a higher susceptibility of people in this group to social influences and less hostility and negativity experienced by them.

  7. Combination of Risperidone and Paroxetine for inappropriate sexual behaviors in an adolescent with autism and mental retardation/Otizm ve zeka geriligi olan bir ergende uygunsuz cinsel davranislar icin Risperidone ve Paroxetine birlikte kullanimi

    National Research Council Canada - National Science Library

    Herguner, Sabri; Herguner, Arzu; Cicek, Erdinc

    2012-01-01

    .... In this paper, we describe an adolescent with autistic disorder and mental retardation who developed severe inappropriate sexual behaviors and has been treated successfully with risperidone-paroxetine combination...

  8. Release of macromolecules from albumin-heparin microspheres

    NARCIS (Netherlands)

    Kwon, Glen S.; Bae, You Han; Cremers, Harry; Feijen, Jan; Kim, Sung Wan

    1992-01-01

    Hydrophilic microspheres based on albumin-heparin conjugates have been prepared as a macromolecular delivery system. The soluble albumin-heparin conjugate was synthesized and crosslinked in a water-in-oil emulsion with glutaraldehyde to form microspheres in the same manner as for albumin microsphere

  9. Rheological Behavior of an Epoxy Resin with Hollow Glass Microspheres

    Science.gov (United States)

    Costa, Cleber C.; Calado, Verônica; Tavares, Frederico W.

    2008-07-01

    An investigation was carried out on the rheological behavior of a TET/DGEBA epoxy formulations with hollow glass microspheres using different types and different volume fractions of microspheres to manufacture composites. It was proposed an equation to describe viscosity as a function of microsphere volume fracion. The fit to the experimental data was excellent.

  10. Preparation of microstructured hydroxyapatite microspheres using oil in water emulsions

    Indian Academy of Sciences (India)

    T S Pradeesh; M C Sunny; H K Varma; P Ramesh

    2005-08-01

    Hydroxyapatite (HAP) microspheres with peculiar spheres-in-sphere morphology were prepared by using oil-in-water emulsions and solvent evaporation technique. Ethylene vinyl acetate co-polymer (EVA) was used as the binder material. Preparation of HAP/EVA microspheres was followed by the thermal debinding and sintering at 1150°C for 3 h to obtain HAP microspheres. Each microsphere of 100–1000 m was in turn composed of spherical hydroxyapatite granules of 2–15 m size which were obtained by spray drying the precipitated HAP. The parameters such as percentage of initial HAP loading, type of stabilizer, concentration of stabilizer, stirring speed and temperature of microsphere preparation were varied to study their effect on the particle size and geometry of the microspheres obtained. It was observed that these parameters do have an effect on the size and shape of the microspheres obtained, which in turn will affect the sintered HAP microstructure. Of the three stabilizers used viz. polyoxyethylene(20) sorbitan monopalmitate (Tween-40), sodium laurate and polyvinyl alcohol (PVA), only PVA with a concentration not less than 0.1 wt% showed controlled stabilization of HAP granules resulting in spherical microspheres of required size. Morphologically better spherical microspheres were obtained at 20°C. Increasing the stirring speed produced smaller microspheres. Smaller microspheres having size < 50 m were obtained at a stirring speed of 1500 ± 50 rpm. A gradual decrease in pore size was observed in the sintered microspheres with increase in HAP loading.

  11. Ziprasidone versus olanzapine, risperidone or quetiapine in patients with chronic schizophrenia: a 12-week open-label, multicentre clinical trial

    DEFF Research Database (Denmark)

    Lublin, Henrik; Haug, Hans-Joachim; Koponen, Hannu

    2009-01-01

    The efficacy, safety and tolerability of ziprasidone versus the comparators olanzapine, risperidone or quetiapine were investigated in adult patients with chronic schizophrenia, schizoaffective and schizophreniform disorders, with lack of efficacy or intolerance to their previous antipsychotic tr...

  12. Computational dynamics of acoustically driven microsphere systems.

    Science.gov (United States)

    Glosser, Connor; Piermarocchi, Carlo; Li, Jie; Dault, Dan; Shanker, B

    2016-01-01

    We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the microsphere system with a time-dependent integral equation solver for the acoustic field that makes use of fields represented as surface expansions in spherical harmonic basis functions. The presented approach allows us to describe the interparticle interaction induced by the field as well as the dynamics of trapping in counter-propagating acoustic pulses. The integral equation formulation leads to equations of motion for the microspheres describing the effect of nondissipative drag forces. We show (1) that the field-induced interactions between the microspheres give rise to effective dipolar interactions, with effective dipoles defined by their velocities and (2) that the dominant effect of an ultrasound pulse through a cloud of microspheres gives rise mainly to a translation of the system, though we also observe both expansion and contraction of the cloud determined by the initial system geometry.

  13. Efficacy and tolerability of Blonanserin in the patients with schizophrenia: a randomized, double-blind, risperidone-compared trial.

    Science.gov (United States)

    Yang, Jaewon; Bahk, Won-Myong; Cho, Hyun-Sang; Jeon, Yang-Whan; Jon, Duk-In; Jung, Hee-Yeon; Kim, Chan-Hyung; Kim, Hee-Cheol; Kim, Yong-Ku; Kim, Young-Hoon; Kwon, Jun-Soo; Lee, Sang-Yeol; Lee, Seung-Hwan; Yi, Jung-Seo; Yoon, Bo-Hyun; Kim, Seung-Hyun

    2010-07-01

    The objective of this study was to evaluate the efficacy and tolerability of blonanserin for the treatment of Korean patients with schizophrenia using a double-blind risperidone-compared design. Patients aged 18 to 65 years with schizophrenia were randomly assigned to blonanserin or risperidone treatment for 8 weeks. The efficacy was assessed using the mean change in Positive and Negative Syndrome Scale score total scores from baseline to week 8. Safety assessments included monitoring of vital signs, a physical examination, laboratory tests, and adverse events. Of 206 randomly enrolled patients, 103 receiving blonanserin and 103 receiving risperidone were included in the analysis. In this study, noninferiority between blonanserin and risperidone was demonstrated. The mean change in the Positive and Negative Syndrome Scale total score at the final evaluation time point was -23.48 +/- 19.73 for the blonanserin group and -25.40 +/- 18.38 for the risperidone group. Adverse events, which occurred less frequently in the blonanserin than in the risperidone group, included dysarthria (P = 0.0288), dizziness (P = 0.0139), increased alanine aminotransferase and aspartate aminotransferase (P = 0.0095 and P = 0.0032, respectively), and increased level blood prolactin (P = 0.0012). On the other hand, the adverse events that occurred more frequently in the blonanserin than in the risperidone group was hand tremor (P = 0.0006). Blonanserin was effective in the treatment of Korean patients with schizophrenia compared with risperidone and was more tolerable with a better safety profile, particularly with respect to prolactin elevation. These findings suggest that blonanserin is useful in the treatment of schizophrenia.

  14. A case of resistant schizophrenia responding at a higher than recommended dose of risperidone without significant side effects

    Directory of Open Access Journals (Sweden)

    Anirban Ray

    2013-01-01

    Full Text Available A patient, diagnosed with schizophrenia, non-responsive to two atypical antipsychotics and partially responsive to the third (risperidone in therapeutic dose, ultimately showed complete response without any unacceptable side-effect in a dose (20mg that was untried previously. This case makes an important observation that high dose of risperidone can be tried in a patient with good results if his clinical condition permits.

  15. Biosensing by WGM Microspherical Resonators

    Directory of Open Access Journals (Sweden)

    Giancarlo C. Righini

    2016-06-01

    Full Text Available Whispering gallery mode (WGM microresonators, thanks to their unique properties, have allowed researchers to achieve important results in both fundamental research and engineering applications. Among the various geometries, microspheres are the simplest 3D WGM resonators; the total optical loss in such resonators can be extremely low, and the resulting extraordinarily high Q values of 108–109 lead to high energy density, narrow resonant-wavelength lines and a lengthy cavity ringdown. They can also be coated in order to better control their properties or to increase their functionality. Their very high sensitivity to changes in the surrounding medium has been exploited for several sensing applications: protein adsorption, trace gas detection, impurity detection in liquids, structural health monitoring of composite materials, detection of electric fields, pressure sensing, and so on. In the present paper, after a general introduction to WGM resonators, attention is focused on spherical microresonators, either in bulk or in bubble format, to their fabrication, characterization and functionalization. The state of the art in the area of biosensing is presented, and the perspectives of further developments are discussed.

  16. Biosensing by WGM Microspherical Resonators

    Science.gov (United States)

    Righini, Giancarlo C.; Soria, Silvia

    2016-01-01

    Whispering gallery mode (WGM) microresonators, thanks to their unique properties, have allowed researchers to achieve important results in both fundamental research and engineering applications. Among the various geometries, microspheres are the simplest 3D WGM resonators; the total optical loss in such resonators can be extremely low, and the resulting extraordinarily high Q values of 108–109 lead to high energy density, narrow resonant-wavelength lines and a lengthy cavity ringdown. They can also be coated in order to better control their properties or to increase their functionality. Their very high sensitivity to changes in the surrounding medium has been exploited for several sensing applications: protein adsorption, trace gas detection, impurity detection in liquids, structural health monitoring of composite materials, detection of electric fields, pressure sensing, and so on. In the present paper, after a general introduction to WGM resonators, attention is focused on spherical microresonators, either in bulk or in bubble format, to their fabrication, characterization and functionalization. The state of the art in the area of biosensing is presented, and the perspectives of further developments are discussed. PMID:27322282

  17. Acrolein Microspheres Are Bonded To Large-Area Substrates

    Science.gov (United States)

    Rembaum, Alan; Yen, Richard C. K.

    1988-01-01

    Reactive cross-linked microspheres produced under influence of ionizing radiation in aqueous solutions of unsaturated aldehydes, such as acrolein, with sodium dodecyl sulfate. Diameters of spheres depend on concentrations of ingredients. If polystyrene, polymethylmethacrylate, or polypropylene object immersed in solution during irradiation, microspheres become attached to surface. Resulting modified surface has grainy coating with reactivity similar to free microspheres. Aldehyde-substituted-functional microspheres react under mild conditions with number of organic reagents and with most proteins. Microsphere-coated macrospheres or films used to immobilize high concentrations of proteins, enzymes, hormones, viruses, cells, and large number of organic compounds. Applications include separation techniques, clinical diagnostic tests, catalytic processes, and battery separators.

  18. Improving photoprotection: 4-methylbenzylidene camphor microspheres.

    Science.gov (United States)

    Centini, Marisanna; Miraglia, Giovanna; Quaranta, Valeria; Buonocore, Anna; Anselmi, Cecilia

    2014-05-22

    Abstract We propose a new approach for photoprotection. 4-Methylbenzylidene camphor (4-MBC), one of the most widely used UV filters, was encapsulated in microspheres, with a view to overcoming problems (percutaneous absorption, photodegradation and lack of lasting effect) arising with organic sunscreens, and to achieve safe photoprotection. We focused on this filter in the light of the Cosmetics Europe opinion concerning its possible effects on the thyroid gland. Microspheres were prepared by emulsification-solvent evaporation, using different amounts of 4-MBC and characterized for morphology, encapsulation efficiency and particle size. The particles were then mixed in O/W emulsions. The in vitro sun protection factors, in vitro release and photostability were investigated and compared with emulsions containing the free sunscreen. The new microspheres offer good morphology and loading (up to 40%), and the same photoprotection as the free filter while at the same time protecting it from photodegradation. The systems also give a slower release from the emulsions.

  19. Removal of radioactive contaminants by polymeric microspheres.

    Science.gov (United States)

    Osmanlioglu, Ahmet Erdal

    2016-11-01

    Radionuclide removal from radioactive liquid waste by adsorption on polymeric microspheres is the latest application of polymers in waste management. Polymeric microspheres have significant immobilization capacity for ionic substances. A laboratory study was carried out by using poly(N-isopropylacrylamide) for encapsulation of radionuclide in the liquid radioactive waste. There are numbers of advantages to use an encapsulation technology in radioactive waste management. Results show that polymerization step of radionuclide increases integrity of solidified waste form. Test results showed that adding the appropriate polymer into the liquid waste at an appropriate pH and temperature level, radionuclide was encapsulated into polymer. This technology may provide barriers between hazardous radioactive ions and the environment. By this method, solidification techniques became easier and safer in nuclear waste management. By using polymer microspheres as dust form, contamination risks were decreased in the nuclear industry and radioactive waste operations.

  20. Quantum Magnetomechanics with Levitating Superconducting Microspheres

    CERN Document Server

    Romero-Isart, O; Navau, C; Sanchez, A; Cirac, J I

    2011-01-01

    We show that by magnetically trapping a superconducting microsphere close to a quantum circuit, it is experimentally feasible to perform ground state cooling and to prepare quantum superpositions of the center-of-mass motion of the microsphere. Due to the absence of clamping losses and time dependent electromagnetic fields, the mechanical motion of micrometer-sized metallic spheres in the Meissner state is predicted to be extremely well isolated from the environment. Hence, we propose to combine the technology of magnetic mictrotraps and superconducting qubits to bring relatively large objects to the quantum regime.

  1. A microsphere suspension model of metamaterial fluids

    Directory of Open Access Journals (Sweden)

    Qian Duan

    2017-05-01

    Full Text Available Drawing an analogy to the liquid phase of natural materials, we theoretically propose a microsphere suspension model to realize a metamaterial fluid with artificial electromagnetic indexes. By immersing high-ε, micrometer-sized dielectric spheres in a low-ε insulating oil, the structured fluid exhibits liquid-like properties from dispersing phase as well as the isotropic negative electromagnetic parameters caused by Mie resonances from dispersed microspheres. The work presented here will benefit the development of structured fluids toward metamaterials.

  2. Kepler Flares. IV. A Comprehensive Analysis of the Activity of the dM4e Star GJ 1243

    Science.gov (United States)

    Silverberg, Steven M.; Kowalski, Adam F.; Davenport, James R. A.; Wisniewski, John P.; Hawley, Suzanne L.; Hilton, Eric J.

    2016-10-01

    We present a comprehensive study of the active dM4e star GJ 1243. We use previous observations and ground-based echelle spectroscopy to determine that GJ 1243 is a member of the Argus association of field stars, suggesting it is ∼ 30{--}50 {{Myr}} old. We analyze 11 months of 1 minute cadence data from Kepler, presenting Kepler flare frequency distributions, as well as determining correlations between flare energy, amplitude, duration, and decay time. We find that the exponent α of the power-law flare energy distribution varies in time, primarily due to completeness of sample and the low frequency of high-energy flares. We also find a deviation from a single power law at high energy. We use ground-based spectroscopic observations that were simultaneous with the Kepler data to provide simultaneous photometric and spectroscopic analysis of three low-energy flares, the lowest-energy dMe flares with detailed spectral analysis to date on any star. The spectroscopic data from these flares extend constraints for radiative hydrodynamic flare models to a lower energy regime than has previously been studied. We use this simultaneous spectroscopy and Kepler photometry to develop approximate conversions from the Kepler bandpass to the traditional U and B bands. This conversion will be a critical factor in comparing any Kepler flare analyses to the canon of previous ground-based flare studies.

  3. Kepler Flares IV: A Comprehensive Analysis of the Activity of the dM4e Star GJ 1243

    CERN Document Server

    Silverberg, Steven M; Davenport, James R A; Wisniewski, John P; Hawley, Suzanne L; Hilton, Eric J

    2016-01-01

    We present a comprehensive study of the active dM4e star GJ 1243. We use previous observations and ground-based echelle spectroscopy to determine that GJ 1243 is a member of the Argus association of field stars, suggesting it is $\\sim 30-50$ Myr old. We analyze eleven months of 1-minute cadence data from Kepler, presenting Kepler flare frequency distributions, as well as determining correlations between flare energy, amplitude, duration, and decay time. We find that the exponent $\\alpha$ of the power-law flare energy distribution varies in time, primarily due to completeness of sample and the low frequency of high-energy flares. We also find a deviation from a single power law at high energy. We use ground-based spectroscopic observations simultaneous with the Kepler data to provide simultaneous photometric and spectroscopic analysis of three low-energy flares, the lowest-energy dMe flares with detailed spectral analysis to date on any star. The spectroscopic data from these flares extend constraints for radi...

  4. High Resolutions Obtained by Microspheres, and Phase Contrast Microscope with a Microsphere

    CERN Document Server

    Ben-Aryeh, Y

    2015-01-01

    High resolutions obtained in optical systems with microspheres are studied by Helmholtz equation and boundary conditions for the EM fields. The large lateral spatial wave vectors of the evanescent waves, which include information on the fine structures of the object, are converted at the microsphere surface to smaller spatial wave vectors. Due to reduction in the magnitudes of these spatial wave vectors a part of the EM waves propagate in the microsphere without decay, but preserve the fine structures which can be recovered in the image plane. A new method for measuring phase objects, like those of semi-transparent biological tissues, with high resolutions is described by an optical system composed of a combination of the microsphere with an interferometer.

  5. Preparation of Micron-size Functional Fluorescent Microspheres

    Institute of Scientific and Technical Information of China (English)

    WANG Di-qiang; LIU Bai-ling; LI He; HU Jie

    2004-01-01

    As a kind of special functional microspheres, fluorescent polymer microspheres could be used in cell label and separation, blood flow assay, flow cytometer marking, chemical reaction assay,and in analyst of the transform and diffusion of particles in soil 1. However, one of the most important applications of fluorescent microspheres is in the high-throughput screening of drugs (HTS) 2. Through affinity interaction, radioactive ligands (latent drugs) are bound to fluorescent microspheres covered by receptor, and luminescence is produced by radioactivity, so ligands can be assayed and screened.In this study, we developed a technique for preparing micron-size fluorescent microspheres with different functional groups. The methods included the synthesis of micron-size polystyrene microspheres through the dispersion polymerization of styrene in different media such as ethanol,ethanol-water, and isopropanol; the functional polystyrene microspheres were prepared by introduction of functional monomers into the reaction system of styrene; the functional fluorescent microspheres were obtained by the way of dying functional microspheres in the fluorescent material's ethanol solvent.The average diameter of microspheres was in the range of 1~10 μm, and the distribution was normal distribution. The functional groups included -OH, -CHO, -COOH, -CONH2, and SO3H. The absorbing spectrum and exciting spectrum were tested, the results showed that the maximal absorbance of fluorescent microsphere was near 306.5 nm, and its maximal excitation was near 362 nm. The excitation spectrum of fluorescent material (DPO) and fluorescent microspheres were shown in figure 1, and it indicated that the developed fluorescent microspheres showed the same excitation behavior like DPO, which related to the fluorescent microspheres had stable luminescence property.

  6. Preparation of biodegradable porous poly(butylene succinate microspheres

    Directory of Open Access Journals (Sweden)

    Pepić Dragana

    2008-01-01

    Full Text Available The aim of this study was to determine the optimal conditions for the fabrication of porous microspheres based on poly(butylene succinate, PBS. The biodegradable non-porous PBS microspheres were prepared by the oil-in-water (o/w emulsion solvent evaporation method using poly(vinyl alcohol, PVA, as the surfactant. Fabrication conditions, such as stirring rate, organic/aqueous ratio, PBS concentration and surfactant (PVA concentration, which have an important influence on both the particle size and the morphology of the microspheres, were varied. Scanning electron microscopy, SEM, observations confirmed the size, size distribution and surface morphology of the microspheres. The optimal conditions for the preparation of the non-porous microspheres were found to be: concentration the PBS solution, 10 mass%; PVA concentration, 1 mass%; the organic/ aqueous ratio CHCl3/H2O = 1/20 and stirring rate 800 rpm. Porous PBS microspheres were fabricated under the optimal conditions using various amounts of hexane and poly(ethylene oxide, PEO, as porogens. The influence of the amount of porogen on the pore size and the particle size was investigated using SEM and the apparent density. The microspheres exhibited various porosities and the pore sizes. The average particle size of the microspheres with PEO as the porogen was from 100 to 122μm and that of the microspheres with hexane as the porogen was from 87 to 97μm. The apparent density of the porous microspheres with PEO as the porogen, from 0.16 to 0.23 g/cm3, was much smaller than the non-porous microspheres, 0.40 g/cm3. In the in vitro degradation experiments, the porous microspheres were incubated in phosphate buffer solution (pH 7 at 37°C. After incubating for one month, the microspheres showed significant extent of the hydrolytic degradation of the porous PBS microspheres.

  7. Double-blind comparison of ziprasidone and risperidone in the treatment of Chinese patients with acute exacerbation of schizophrenia

    Directory of Open Access Journals (Sweden)

    Hongyan Zhang

    2011-03-01

    Full Text Available Hongyan Zhang1, Huafang Li2, Liang Shu1, Niufan Gu2, Gang Wang3, Yongzhen Weng3, Shiping Xie4, Xinbao Zhang4, Ting Li5, Cui Ma5, Wei Yu6, Bruce Parsons7, Manjula Schou81Institute of Mental Health, Peking University, Beijing, China; 2Shanghai Mental Health Center, Shanghai, China; 3Capital Medical University, Beijing An Ding Hospital, Beijing, China; 4Nanjing Brain Hospital, Nanjing, China; 5Guangzhou Brain Hospital, Guangzhou, China; 6Pfizer China, Beijing, China; 7Pfizer Inc, New York, NY, USA; 8Pfizer Australia, Sydney, AustraliaBackground: The aim of the study was to evaluate the efficacy and safety of ziprasidone versus risperidone in Chinese subjects with acute exacerbation of schizophrenia.Methods: In patients meeting the Chinese Classification of Mental Disorders criteria for schizophrenia and with a Positive and Negative Syndrome Scale (PANSS total score ≥60 were randomly assigned to six weeks of double-blind treatment with ziprasidone 40–80 mg twice daily or risperidone 1–3 mg bid, flexibly dosed. Noninferiority was demonstrated if the upper limit of the two-sided 95% confidence interval (CI for the difference in PANSS total score improvement from baseline in the evaluable population was smaller than the prespecified noninferiority margin of 10 units.Results: The intent-to-treat population comprised 118 ziprasidone-treated and 121 risperidone-treated subjects. Improvement (reduction from baseline to week 6 in PANSS total score was (-35.6 [95% CI: -38.6, -32.6] for ziprasidone and (-37.1 [95% CI: -39.9, -34.4] for risperidone. Noninferiority was demonstrated in the evaluable population with a difference score of 1.5 [95% CI: -2.5, 5.5]. Mean prolactin levels decreased at week 6 compared with baseline for ziprasidone (-3.5 ng/mL, but significantly increased for risperidone (61.1 ng/mL; P < 0.001. More risperidone-treated subjects (14.9% than ziprasidone-treated subjects (4.2% reported weight gain ≥7%. Akathisia and somnolence in

  8. Physiogenomic comparison of weight profiles of olanzapine- and risperidone-treated patients.

    Science.gov (United States)

    Ruaño, G; Goethe, J W; Caley, C; Woolley, S; Holford, T R; Kocherla, M; Windemuth, A; de Leon, J

    2007-05-01

    Atypical antipsychotics induce pre-diabetic symptoms in some but not all patients, characterized most notably by elevated weight. The side effect profiles of the various drugs in the class differ, however, raising the possibility of drug-specific mechanisms for similar side effects. We used physiogenomic analysis, an approach previously employed to study the genetics of drug and diet response, to discover and compare genetic associations with weight profiles observed in patients treated with olanzapine and risperidone as an approach to unraveling contrasting mechanistic features of both drugs. A total of 29 single nucleotide polymorphisms (SNPs) were selected from 13 candidate genes relevant to two potential pharmacological axes of psychotropic-related weight profiles, appetite peptides and peripheral lipid homeostasis. We applied physiogenomic analysis to a cross-section of 67 and 101 patients being treated with olanzapine and risperidone, respectively, and assessed genetic associations with the weight profiles. Weight profiles in patients treated with olanzapine were significantly associated with SNPs in the genes for apolipoprotein E, apolipoprotein A4 and scavenger receptor class B, member 1. Weight profiles in patients treated with risperidone were significantly associated with SNPs in the genes for leptin receptor, neuropeptide Y receptor Y5 and paraoxonase 1. These results are consistent with contrasting mechanisms for the weight profile of patients treated with these drugs. Genes associated with olanzapine weight profiles may be related to peripheral lipid homeostatic axes, whereas those associated with risperidone's may be related to brain appetite peptide regulation. Future physiogenomic studies will include neurotransmitter receptor SNPs and validation in independent samples.

  9. Development of novel risperidone implants using blends of polycaprolactones and in vitro in vivo correlation studies.

    Science.gov (United States)

    Navitha, Aerrolla; Jogala, Satheesh; Krishnamohan, Chinnala; Aukunuru, Jithan

    2014-04-01

    The objective of this study was to develop a novel implant containing risperidone intended for long-term treatment in Schizophrenia utilizing in vitro in vivo correlation (IVIVC) studies. Different implants (F1-F8) containing an antipsychotic drug, risperidone, were prepared using a hot melt extrusion technique by taking polycaprolactones of different molecular weights (Mwt. 15000, 45000, 80000) either alone or as their blends, and PLGA (75:25). The implants contained 40% of the drug. After fabrication, the implants were characterized for various in vitro properties such as drug release and physical strength. Prior to conducting drug release studies, optimum drug release method was developed based on IVIVC studies. An optimized formulation based on drug release and physical strength at the end of fabrication was selected from the various implants fabricated. The bioactivity, reversibility, and IVIVC of optimized formulation were determined using pharmacokinetic studies in rats. Short-term stability studies were conducted with optimized formulation. Drug release depended on polymer molecular weight. Implant fabricated using 50:50 polycaprolactone 45,000 and polycaprolactone 80,000 was considered optimized implant. Optimized formulation selected released the drug for 3-months in vitro and was physically rigid. The optimized implant was able to release the drug in vivo for a period of 3 months, the implants are reversible throughout the delivery interval and, a 100% IVIVC was achieved with optimized implant, suggesting the development of 3-month drug-releasing implant for risperidone. The optimized implant was stable for 6 months at room temperature (25°C) and 45°C. A novel implant for risperidone was successfully prepared and evaluated.

  10. Development of novel risperidone implants using blends of polycaprolactones and in vitro in vivo correlation studies

    Directory of Open Access Journals (Sweden)

    Aerrolla Navitha

    2014-01-01

    Full Text Available The objective of this study was to develop a novel implant containing risperidone intended for long-term treatment in Schizophrenia utilizing in vitro in vivo correlation (IVIVC studies. Different implants (F1-F8 containing an antipsychotic drug, risperidone, were prepared using a hot melt extrusion technique by taking polycaprolactones of different molecular weights (Mwt. 15000, 45000, 80000 either alone or as their blends, and PLGA (75:25. The implants contained 40% of the drug. After fabrication, the implants were characterized for various in vitro properties such as drug release and physical strength. Prior to conducting drug release studies, optimum drug release method was developed based on IVIVC studies. An optimized formulation based on drug release and physical strength at the end of fabrication was selected from the various implants fabricated. The bioactivity, reversibility, and IVIVC of optimized formulation were determined using pharmacokinetic studies in rats. Short-term stability studies were conducted with optimized formulation. Drug release depended on polymer molecular weight. Implant fabricated using 50:50 polycaprolactone 45,000 and polycaprolactone 80,000 was considered optimized implant. Optimized formulation selected released the drug for 3-months in vitro and was physically rigid. The optimized implant was able to release the drug in vivo for a period of 3 months, the implants are reversible throughout the delivery interval and, a 100% IVIVC was achieved with optimized implant, suggesting the development of 3-month drug-releasing implant for risperidone. The optimized implant was stable for 6 months at room temperature (25°C and 45°C. A novel implant for risperidone was successfully prepared and evaluated.

  11. Risperidone-induced priapism in an autistic child: a case report

    OpenAIRE

    Aabbassi, Bouchra; Benali, Abdeslam; Asri, Fatima

    2016-01-01

    Background Priapism is a prolonged stimulation with painful, persistent penile erection unaccompanied by sexual desire. It is a rare but serious urological emergency. Risperidone is an atypical antipsychotic widely prescribed for the treatment of behavior problems in children with autism spectrum disorder. It seems associated with priapism in children. Case presentation We present a case of a 12-year-old Moroccan boy diagnosed with autism spectrum disorder who developed priapism while on an e...

  12. Risperidone Long-Acting Injections: Successful Alternative Deltoid Muscle Injections for Refractory Schizophrenia

    OpenAIRE

    Saxena, Arjun; Grace, Jeffery; Olympia, Josie L.; Trigoboff, Eileen; Watson, Thomas; Cushman, Sharon; Newcomer, David

    2008-01-01

    Treatment-resistant paranoid schizophrenia is often addressed with long-term intramuscular preparations of conventional antipsychotics (haloperidol and fluphenazine), which can be associated with the development of painful, lumpy nodules at the injection site. In this article, we present a case example of a 58-year-old male patient with paranoid schizophrenia who was treated with risperidone long-acting injection given into the deltoid muscle instead of the US Food and Drug Administration (FD...

  13. Amenorrhoea - consequence of combined treatment with sulpiride and risperidone in a patient suffering from schizophrenia.

    Science.gov (United States)

    Peitl, Marija Vucić; Pavlović, Eudard; Peitl, Antun; Peitl, Vjekoslav

    2010-03-01

    It is well documented that sulpiride causes hormonal adverse events, like amenorrhoea and galactorrhea, due to its mechanism of action. Furthermore, risperidone can produce amenorrhoea and galactorrhea also, due to its mechanism of action, which differs from that of sulpiride. This case report is of a patient that was treated with large doses of sulpiride, but did not develop an adverse event like amenorrhoea. However, when risperidone was introduced into therapy it leads to the onset of amenorrhoea. Gynecologist saw it as the beginning of menopause. General practitioner questioned the existence of an intra-cerebral process that could produce amenorrhoea as well. Therefore, the patient was sent to perform an MRI of the brain, under work diagnosis of pituitary adenoma, which was later ruled out as a cause of the illness. Well experienced psychiatrist linked the loss of menstruation with the adverse event profile of sulpiride and therefore gradually discontinued sulpiride from therapy, while risperidone was left and subsequently menstrual cycle was restored. Good knowledge of adverse events profile of antipsychotic medication used, especially when used in a combination, allows us to correctly question appearance of adverse events, to adequately treat them and lowers the cost of unneeded medical procedures.

  14. Risperidone oral disintegrating mini-tablets: A robust-product for pediatrics

    Directory of Open Access Journals (Sweden)

    El-Say Khalid M.

    2015-12-01

    Full Text Available This study was aimed at developing risperidone oral disintegrating mini-tablets (OD-mini-tablets as age-appropriate formulations and to assess their suitability for infants and pediatric use. An experimental Box-Behnken design was applied to assure high quality of the OD-mini-tablets and reduce product variability. The design was employed to understand the influence of the critical excipient combinations on the production of OD-mini-tablets and thus guarantee the feasibility of obtaining products with dosage form uniformity. The variables selected were mannitol percent in Avicel (X1, swelling pressure of the superdisintegrant (X2, and the surface area of Aerosil as a glidant (X3. Risperidone-excipient compatibilities were investigated using FTIR and the spectra did not display any interaction. Fifteen formulations were prepared and evaluated for preand post-compression characteristics. The prepared ODmini- tablet batches were also assessed for disintegration in simulated salivary fluid (SSF, pH 6.2 and in reconstituted skimmed milk. The optimized formula fulfilled the requirements for crushing strength of 5 kN with minimal friability, disintegration times of 8.4 and 53.7 s in SSF and skimmed milk, respectively. This study therefore proposes the risperidone OD-mini-tablet formula having robust mechanical properties, uniform and precise dosing of medication with short disintegration time suitable for pediatric use.

  15. Beat-Frequency/Microsphere Medical Ultrasonic Imaging

    Science.gov (United States)

    Yost, William T.; Cantrell, John H.; Pretlow, Robert A., III

    1995-01-01

    Medical ultrasonic imaging system designed to provide quantitative data on various flows of blood in chambers, blood vessels, muscles, and tissues of heart. Sensitive enough to yield readings on flows of blood in heart even when microspheres used as ultrasonic contrast agents injected far from heart and diluted by circulation of blood elsewhere in body.

  16. Bilayer Tablet via Microsphere: A Review

    Directory of Open Access Journals (Sweden)

    Piyushkumar Vinubhai Gundaraniya

    2013-01-01

    Full Text Available The aim of the present work is to develop bilayer tablets containing sustained release microspheres as one layer and immediate release as another layer. The proposed dosage form is intended to decrease the dosing frequency and the combined administration of an anti-diabetic agent. Several pharmaceutical companies are currently developing bi-layer tablets, for a variety of reasons: patent extension, therapeutic, marketing to name a few. To reduce capital investment, quite often existing but modified tablet presses are used to develop and produce such tablets. One such approach is using microspheres as carriers for drugs also known as micro particles. It is the reliable means to deliver the drug to the target site with specificity, if modified, and to maintain the desired concentration at the site of interest. Microspheres received much attention not only for prolonged release, but also for targeting of anti-diabetic drugs. Bilayer tablet via microsphere is new era for the successful development of controlled release formulation along with various features to provide a way of successful drug delivery system. Especially when in addition high production output is required. An attempt has been made in this review article to introduce the society to the current technological developments in bilayer and floating drug delivery system.

  17. Tumor Vaccination With Cytokine-Loaded Microspheres

    Science.gov (United States)

    2005-12-01

    buffer (1% hydroxypropylmethylcellulose [DOW Co., Midlands, MI, USA] and 1% Pluronic F127 [Sigma] in phosphate-buffered saline [PBS], pH 7.2). Control mice...hydration buffer (1% hydroxypropylmethylcellulose (Dow) and 1% Pluronic F-127 (Sigma- Aldrich) in PBS, pH 7.2). Control mice received blank microspheres

  18. Arabinoxylan Microspheres: Structural and Textural Characteristics

    Directory of Open Access Journals (Sweden)

    Yolanda López-Franco

    2013-04-01

    Full Text Available The aim of this research was to study the structural and textural characteristics of maize bran arabinoxylan (MBAX microspheres. The laccase-induced cross-linking process was monitored by storage (G' and loss (G'' moduli changes in a 4% (w/v MBAX solution. The G' and G'' values at the plateau region were 215 and 4 Pa, respectively. After gelation, the content of ferulic acid dimers decreased from 0.135 to 0.03 µg/mg MBAX, suggesting the formation of ferulated structures unreleased by mild alkaline hydrolysis. MBAX microspheres presented an average diameter of 531 µm and a swelling ratio value (q of 18 g water/g MBAX. The structural parameters of MBAX microspheres were calculated from equilibrium swelling experiments, presenting an average mesh size of 52 nm. Microstructure and textural properties of dried MBAX microspheres were studied by scanning electron microscopy and nitrogen adsorption/desorption isotherms, respectively, showing a heterogeneous mesoporous and macroporous structure throughout the network.

  19. Encapsulated PDMS microspheres with reactive handles

    DEFF Research Database (Denmark)

    Gonzalez, Lidia; Ma, Baoguang; Li, Li

    2014-01-01

    Cured poly(dimethyl siloxane) microspheres are prepared by an emulsion polymerization reaction of silicone droplets in a continuous aqueous phase. The commonly used PDMS elastomer, Sylgard 184 from Dow Corning, is used as the dispersed phase. PDMS is polymerized and cross-linked by reacting vinyl...

  20. Composition and structure of calcium aluminosilicate microspheres

    Science.gov (United States)

    Sharonova, O. M.; Oreshkina, N. A.; Zhizhaev, A. M.

    2017-06-01

    The composition was studied of calcium aluminosilicate microspheres of three morphological types in high-calcium fly ash from combustion of brown coal from the Kansk-Achinsk basin in slag-tap boilers at temperatures from 1400 to 1500°C and sampled in the first field of electrostatic precipitators at the Krasnoyarsk Cogeneration Power Station no. 2 (TETs-2). Gross compositions and the composition of local areas were determined using a scanning electron microscopy technique and an energy-dispersive analysis with full mapping of globules. With a high content of basic oxides O ox (68 to 79 wt %) and a low content of acid oxides K ox (21 to 31 wt %), type 1 microspheres are formed. They consist of heterogeneous areas having a porous structure and crystalline components in which the content of CaO, SiO2, or Al2O3 differs by two to three times and the content of MgO differs by seven times. With a lower content of O ox (55 to 63 wt %) and an elevated content of K ox (37 to 45 wt %), type 2 microspheres are formed. They are more homogeneous in the composition and structure and consist of similar crystalline components. Having a close content of O ox (46 to 53 wt %) and K ox (47 to 54 wt %), type 3 microspheres, which are a dense matter consisting of amorphous substance with submicron- and nanostructure of crystalline components, are formed. The basic precursor in formation of high-calcium aluminosilicate microspheres is calcium from the organomineral matter of coals with various contribution of Mg, Fe, S, or Na from the coal organic matter and Al, Fe, S, or Si in the form of single mineral inclusions in a coal particle. On the basis of the available data, the effect was analyzed of the composition of a CaO-MgO-Al2O3-SiO2-FeO system on the melting and viscous properties of the matter in microspheres and formation of globules of different morphology. The results of this analysis will help to find a correlation with properties of microspheres in their use as functional

  1. Preparation of Hollow Porous HAP Microspheres as Drug Delivery Vehicles

    Institute of Scientific and Technical Information of China (English)

    WANG Qing; HUANG Wenhai; WANG Deping

    2007-01-01

    Hollow HAP microspheres in sub-millimeter size were prepared and investigated as a drug delivery vehicle. The LCB (lithium-calcium borate) glass microspheres, which were made through flame spray process, were chosen as precursor for hollow HAP microspheres. The LCB glass microspheres reacted with phosphate buffer (K2HPO4) solution for 5 days at 37 ℃. During the reaction the Ca-P-OH compound precipitated on the surface of LCB glass microspheres and formed porous shells. Then the microspheres turned to be hollow ones with the same diameter as the glass microspheres after LCB glass run out in the chemical reaction. After heat-treated at 600 ℃ for 4 h, the Ca-P-OH compound became HAP, thus the hollow HAP microspheres were produced. The mechanism of forming hollow HAP microspheres through the chemical reaction between phosphate buffer and LCB glass was confirmed by the XRD analysis. The microstructure characteristics of the hollow, porous microspheres were observed by SEM.

  2. PLGA/alginate composite microspheres for hydrophilic protein delivery.

    Science.gov (United States)

    Zhai, Peng; Chen, X B; Schreyer, David J

    2015-11-01

    Poly(lactic-co-glycolic acid) (PLGA) microspheres and PLGA/alginate composite microspheres were prepared by a novel double emulsion and solvent evaporation technique and loaded with bovine serum albumin (BSA) or rabbit anti-laminin antibody protein. The addition of alginate and the use of a surfactant during microsphere preparation increased the encapsulation efficiency and reduced the initial burst release of hydrophilic BSA. Confocal laser scanning microcopy (CLSM) of BSA-loaded PLGA/alginate composite microspheres showed that PLGA, alginate, and BSA were distributed throughout the depths of microspheres; no core/shell structure was observed. Scanning electron microscopy revealed that PLGA microspheres erode and degrade more quickly than PLGA/alginate composite microspheres. When loaded with anti-laminin antibody, the function of released antibody was well preserved in both PLGA and PLGA/alginate composite microspheres. The biocompatibility of PLGA and PLGA/alginate microspheres were examined using four types of cultured cell lines, representing different tissue types. Cell survival was variably affected by the inclusion of alginate in composite microspheres, possibly due to the sensitivity of different cell types to excess calcium that may be released from the calcium cross-linked alginate.

  3. PLGA microspheres encapsulating siRNA.

    Science.gov (United States)

    De Rosa, Giuseppe; Salzano, Giuseppina

    2015-01-01

    The therapeutic use of small interfering RNA (siRNA) represents a new and powerful approach to suppress the expression of pathologically genes. However, biopharmaceutical drawbacks, such as short half-life, poor cellular uptake, and unspecific distribution into the body, hamper the development of siRNA-based therapeutics. Poly(lactide-co-glycolide), (PLGA) microspheres can be a useful tool to overcome these issues. siRNA can be encapsulated into the PLGA microspheres, which protects the loaded nucleic acid against the enzymatic degradation. Moreover, PLGA microspheres can be injected directly into the action site, where the siRNA can be released in controlled manner, thus avoiding the need of frequent invasive administrations. The complete biodegradability of PLGA to monomers easily metabolized by the body, and its approval by FDA and EMA for parenteral administration, assure the safety of this copolymer and do not require the removal of the device after the complete drug release. In chapter, a basic protocol for the preparation of PLGA microspheres encapsulating siRNA is described. This protocol is based on a double emulsion/solvent evaporation technique, a well known and easy to reproduce method. This specific protocol has been developed to encapsulate a siRNA anti-TNFα in PLGA microspheres, and it has been designed and optimized to achieve high siRNA encapsulation efficiency and slow siRNA release in vitro. However, it can be extended also to other siRNA as well as other RNA or DNA-based oligonucleotides (miRNA, antisense, decoy, etc.). Depending on the applications, chemical modifications of the backbone and site-specific modification within the siRNA sequences could be required.

  4. The antidepressant- and anxiolytic-like effects following co-treatment with escitalopram and risperidone in rats.

    Science.gov (United States)

    Kaminska, K; Rogoz, Z

    2016-06-01

    Several clinical reports have documented a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants, in particular selective serotonin reuptake inhibitors (SSRI), in the treatment of drug-resistant depression and treatment-resistant anxiety disorders. In the present study, we investigated the effect of treatment with the antidepressant escitalopram (SSRI) given separately or jointly with a low dose of risperidone (an atypical antipsychotic) in the forced swim test and in the elevated plus-maze test in rats. The obtained results showed that escitalopram at doses of 2.5 or 5 mg/kg evoked antidepressant-like effect in the forced swim test. Moreover, risperidone at low doses (0.05 or 0.1 mg/kg) enhanced the antidepressant-like activity of escitalopram (1 mg/kg) in this test by increasing the swimming time and decreasing the immobility time in those animals. WAY 100635 (a serotonin 5-HT1A receptor antagonist) at a dose of 0.1 mg/kg abolished the antidepressant-like effect induced by co-administration of escitalopram and risperidone. The active behavior in that test did not reflect an increase in general activity, since the combined treatment with escitalopram and risperidone failed to enhance the exploratory activity of rats. In the following experiment, we showed that escitalopram (5 mg/kg) and mirtazapine (5 or 10 mg/kg) or risperidone (0.1 mg/kg) induced an anxiolytic-like effect in the elevated plus-maze test, and the combined treatment with an ineffective dose of risperidone (0.05 mg/kg) enhanced the anxiolytic-like effects of escitalopram (2.5 mg/kg) or mirtazapine (1 and 2.5 mg/kg) in this test. The obtained results suggest that risperidone applied at a low dose enhances the antidepressant-like activity of escitalopram in the forced swim test, and that 5-HT1A receptors may play some role in these effects. Moreover, a low dose of risperidone may also enhance the anxiolytic-like action of the studied

  5. Risperidone and Divalproex Differentially Engage the Fronto-Striato-Temporal Circuitry in Pediatric Mania: A Pharmacological Functional Magnetic Resonance Imaging Study

    Science.gov (United States)

    Pavuluri, Mani N.; Passarotti, Alessandra M.; Fitzgerald, Jacklynn M.; Wegbreit, Ezra; Sweeney, John A.

    2012-01-01

    Objective: The current study examined the impact of risperidone and divalproex on affective and working memory circuitry in patients with pediatric bipolar disorder (PBD). Method: This was a six-week, double-blind, randomized trial of risperidone plus placebo versus divalproex plus placebo for patients with mania (n = 21; 13.6 [plus or minus] 2.5…

  6. Risperidone and Divalproex Differentially Engage the Fronto-Striato-Temporal Circuitry in Pediatric Mania: A Pharmacological Functional Magnetic Resonance Imaging Study

    Science.gov (United States)

    Pavuluri, Mani N.; Passarotti, Alessandra M.; Fitzgerald, Jacklynn M.; Wegbreit, Ezra; Sweeney, John A.

    2012-01-01

    Objective: The current study examined the impact of risperidone and divalproex on affective and working memory circuitry in patients with pediatric bipolar disorder (PBD). Method: This was a six-week, double-blind, randomized trial of risperidone plus placebo versus divalproex plus placebo for patients with mania (n = 21; 13.6 [plus or minus] 2.5…

  7. Adverse Effects of Risperidone in Children with Autism Spectrum Disorders in a Naturalistic Clinical Setting at Siriraj Hospital, Thailand

    Directory of Open Access Journals (Sweden)

    Vitharon Boon-yasidhi

    2014-01-01

    Full Text Available A cross-sectional study was conducted to evaluate adverse effects associated with risperidone in 45 children with autism spectrum disorders (ASD, aged 2–15 years, who were treated at Siriraj Hospital, Thailand, between the years 2006 and 2007. Adverse effects were assessed by parent interview, using a semistructure questionnaire, and medical records review. The mean ± SD age of the children at starting risperidone was 8.15±2.98 years. The mean ± SD of risperidone dose was 0.94±0.74 mg/day and the mean ± SD duration of treatment was 36.8±27.8 months. Adverse effects were reported in 39 children (86.7%. Common adverse effects included increased appetite, somnolence, and rhinorrhea and most of the adverse effects were tolerable. Tardive dyskinesia or other serious adverse events were not found in this study. The child’s mean ± SD weight gain was 4.18±2.82 kg/year, which exceeded developmentally expected norms. The results from this study suggest that risperidone treatment in children with ASD is associated with frequent mild and tolerable adverse effects. However, excessive weight gain could be found to be a concerning adverse effect and weight monitoring is warranted when risperidone is being prescribed.

  8. Parenteral nanoemulsions as promising carriers for brain delivery of risperidone: Design, characterization and in vivo pharmacokinetic evaluation.

    Science.gov (United States)

    Đorđević, Sanela M; Cekić, Nebojša D; Savić, Miroslav M; Isailović, Tanja M; Ranđelović, Danijela V; Marković, Bojan D; Savić, Saša R; Timić Stamenić, Tamara; Daniels, Rolf; Savić, Snežana D

    2015-09-30

    This paper describes design and evaluation of parenteral lecithin-based nanoemulsions intended for brain delivery of risperidone, a poorly water-soluble psychopharmacological drug. The nanoemulsions were prepared through cold/hot high pressure homogenization and characterized regarding droplet size, polydispersity, surface charge, morphology, drug-vehicle interactions, and physical stability. To estimate the simultaneous influence of nanoemulsion formulation and preparation parameters--co-emulsifier type, aqueous phase type, homogenization temperature--on the critical quality attributes of developed nanoemulsions, a general factorial experimental design was applied. From the established design space and stability data, promising risperidone-loaded nanoemulsions (mean size about 160 nm, size distribution emulsifier, were produced by hot homogenization and their ability to improve risperidone delivery to the brain was assessed in rats. Pharmacokinetic study demonstrated erratic brain profiles of risperidone following intraperitoneal administration in selected nanoemulsions, most probably due to their different droplet surface properties (different composition of the stabilizing layer). Namely, polysorbate 80-costabilized nanoemulsion showed increased (1.4-7.4-fold higher) risperidone brain availability compared to other nanoemulsions and drug solution, suggesting this nanoemulsion as a promising carrier worth exploring further for brain targeting. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Subjective response to antipsychotic treatment and compliance in schizophrenia. A naturalistic study comparing olanzapine, risperidone and haloperidol (EFESO Study

    Directory of Open Access Journals (Sweden)

    Sacristán Jose A

    2001-12-01

    Full Text Available Abstract Background In order to compare the effectiveness of different antipsychotic drugs in the treatment of schizophrenia it is very important to evaluate subjective response and compliance in patient cohorts treated according to routine clinical practice. Method Outpatients with schizophrenia entered this prospective, naturalistic study when they received a new prescription for an antipsychotic drug. Treatment assignment was based on purely clinical criteria, as the study did not include any experimental intervention. Patients treated with olanzapine, risperidone or haloperidol were included in the analysis. Subjective response was measured using the 10-item version of the Drug Attitude Inventory (DAI-10, and treatment compliance was measured using a physician-rated 4 point categorical scale. Results A total of 2128 patients initiated treatment (as monotherapy with olanzapine, 417 with risperidone, and 112 with haloperidol. Olanzapine-treated patients had significantly higher DAI-10 scores and significantly better treatment compliance compared to both risperidone- and haloperidol-treated patients. Risperidone-treated patients had a significantly higher DAI-10 score compared to haloperidol-treated patients. Conclusion Subjective response and compliance were superior in olanzapine-treated patients, compared to patients treated with risperidone and haloperidol, in routine clinical practice. Differences in subjective response were explained largely, but not completely, by differences in incidence of EPS.

  10. Pluronic F127/chitosan blend microspheres for mucoadhesive drug delivery

    Science.gov (United States)

    Gu, W. Z.; Hu, X. F.

    2017-01-01

    Pluronic F127/chitosan blend microspheres were prepared via emulsification and cross-linking process using glutaraldehyde as a cross-linker. Compared with chitosan microspheres fabricated under the same experimental conditions, blend microspheres exhibited better physical stability and higher swelling capacity. Puerarin, a traditional Chinese medicine, was incorporated into microparticlesas the model drug. The in vitro release of puerarin from blend microspheres was reduced because of the improved compatibility of the drug with the matrices. According to the results from in vitro adhesion experiments, mucoadhesive behavior of blend microspheres on a mucosa-like surface was similar to that of chitosan microspheres, despite their good ability of anti-protein absorption in solution.

  11. PLGA and PHBV Microsphere Formulations and Solid-State Characterization

    DEFF Research Database (Denmark)

    Yang, Chiming; Plackett, David; Needham, David

    2009-01-01

    To develop and characterize the solid-state properties of poly(DL-lactic-co-glycolic acid) (PLGA) and poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid) (PHBV) microspheres for the localized and controlled release of fusidic acid (FA). The effects of FA loading and polymer composition on the mean...... diameter, encapsulation efficiency and FA released from the microspheres were determined. The solid-state and phase separation properties of the microspheres were characterized using DSC, XRPD, Raman spectroscopy, SEM, laser confocal and real time recording of single microspheres formation. Above a loading...... of 1% (w/w) FA phase separated from PLGA polymer and formed distinct spherical FA-rich amorphous microdomains throughout the PLGA microsphere. For FA-loaded PLGA microspheres, encapsulation efficiency and cumulative release increased with initial drug loading. Similarly, cumulative release from FA...

  12. Method of detecting luminescent target ions with modified magnetic microspheres

    Science.gov (United States)

    Shkrob, Ilya A; Kaminski, Michael D

    2014-05-13

    This invention provides methods of using modified magnetic microspheres to extract target ions from a sample in order to detect their presence in a microfluidic environment. In one or more embodiments, the microspheres are modified with molecules on the surface that allow the target ions in the sample to form complexes with specific ligand molecules on the microsphere surface. In one or more embodiments, the microspheres are modified with molecules that sequester the target ions from the sample, but specific ligand molecules in solution subsequently re-extract the target ions from the microspheres into the solution, where the complexes form independent of the microsphere surface. Once the complexes form, they are exposed to an excitation wavelength light source suitable for exciting the target ion to emit a luminescent signal pattern. Detection of the luminescent signal pattern allows for determination of the presence of the target ions in the sample.

  13. Albumin microspheres labeled with Ga-67 by chelation: concise communication.

    Science.gov (United States)

    Hnatowich, D J; Schlegel, P

    1981-07-01

    Albumin microspheres have been synthesized eith EDTA and DTPA chelating groups covalently bound to their surface. The microspheres may be labeled with Ga-67 at high yield (97 +/- 2%) by transcomplexation from a 0.1 M Ga-67 acetate solution. With EDTA microspheres the resulting label dissociates only slightly after no detectable dissociation over this period. By contrast, microspheres without chelating groups lose their label virtually completely under these conditions. Following intravenous administration of sized Ga-67 DTPA microspheres in mice, about (84 +/- 16)% of the activity localizes in the lungs at 5 min, with (60 +/- 7)% remaining after 2 hr. Since labeling is by chelation, the microspheres may also be tagged with other metallic radionuclides

  14. Laser-assisted fabrication of highly viscous alginate microsphere

    Science.gov (United States)

    Lin, Yafu; Huang, Yong

    2011-04-01

    Encapsulated microspheres have been widely used in various biomedical applications. However, fabrication of encapsulated microspheres from highly viscous materials has always been a manufacturing challenge. The objective of this study is to explore a novel metallic foil-assisted laser-induced forward transfer (LIFT), a laser-assisted fabrication technique, to make encapsulated microspheres using high sodium alginate concentration solutions. The proposed four-layer approach includes a quartz disk, a sacrificial and adhesive layer, a metallic foil, and a transferred suspension layer. It is found that the proposed four-layer modified LIFT approach provides a promising fabrication technology for making of bead-encapsulated microspheres from highly viscous solutions. During the process, the microsphere only can be formed if the direct-writing height is larger than the critical direct-writing height; otherwise, tail structured droplets are formed; and the encapsulated microsphere diameter linearly increases with the laser fluence and decreases with the sodium alginate concentration.

  15. MULTIMODE THEORY OF WHISPERING GALLERY-MODE MICROSPHERE LASER

    Institute of Scientific and Technical Information of China (English)

    CHAI JIN-HUA; LU YI-QUN; LEUNG PUI-TANG

    2000-01-01

    A multimode theory of whispering-gallery-mode microsphere laser is developed based on the linear and nonlinear semiclassical theory of the microsphere laser. The average photon-number of each lasing mode and the pumping level requirement for multimode coexistence are derived. The comparison between the theory and experimental results shows that the theory can be used to treat the practical problems on microsphere laser.

  16. Preparation and characterization of immobilized lipase on magnetic hydrophobic microspheres

    DEFF Research Database (Denmark)

    Guo, Zheng; Bai, Shu; Sun, Yan

    2003-01-01

    A novel magnetic poly(vinyl acetate (VAc)–divinyl benzene (DVB)) material (8–34 μm) was synthesized by copolymerization of vinyl acetate and divinyl benzene using oleic acid-stabilized magnetic colloids as magnetic cores. The magnetic colloids and the copolymer microspheres were characterized...... with transmission and scanning electron microscopes, respectively. Magnetization of the microspheres could be described by the Langevin function. All the observations indicated that the microspheres were superparamagnetic. Magnetic sedimentation of the microspheres was achieved within 3 min, over 300 times faster...

  17. Controlled Delivery of Gentamicin Using Poly(3-hydroxybutyrate Microspheres

    Directory of Open Access Journals (Sweden)

    Ipsita Roy

    2011-07-01

    Full Text Available Poly(3-hydroxybutyrate, P(3HB, produced from Bacillus cereus SPV using a simple glucose feeding strategy was used to fabricate P(3HB microspheres using a solid-in-oil-water (s/o/w technique. For this study, several parameters such as polymer concentration, surfactant and stirring rates were varied in order to determine their effect on microsphere characteristics. The average size of the microspheres was in the range of 2 µm to 1.54 µm with specific surface areas varying between 9.60 m2/g and 6.05 m2/g. Low stirring speed of 300 rpm produced slightly larger microspheres when compared to the smaller microspheres produced when the stirring velocity was increased to 800 rpm. The surface morphology of the microspheres after solvent evaporation appeared smooth when observed under SEM. Gentamicin was encapsulated within these P(3HB microspheres and the release kinetics from the microspheres exhibiting the highest encapsulation efficiency, which was 48%, was investigated. The in vitro release of gentamicin was bimodal, an initial burst release was observed followed by a diffusion mediated sustained release. Biodegradable P(3HB microspheres developed in this research has shown high potential to be used in various biomedical applications.

  18. Poly(styrene-acrylic acid) magnetic polymer microspheres

    Institute of Scientific and Technical Information of China (English)

    Yanling CHENG; Liuqiang MA; Ruohui LI

    2008-01-01

    Magnetic polymer microspheres have been considered as a kind of new biopolymer materials with great advantages in bioseparation engineering and biome-dicine engineering because they have not only polymer functional groups but also magnetic characteristics. Styrene-acrylic acid copolymer (p(S-AA)) magnetic microspheres were synthesized by dispersion polymeriza-tion with Fe3O4 as core and p(S-AA) as shell. The micro-spheres were characterized by SEM, size analysis, molecular weight and solid content measurement. All of them indicate that the microspheres are small in size, nar-row in distribution, stable in chemistry and rich in func-tional groups on their surface.

  19. Preparation and Characterization of Albumin Microspheres Encapsulated with Propranolol HCl

    Directory of Open Access Journals (Sweden)

    Sayyed Abolghassem Sajadi Tabassi

    2003-10-01

    Full Text Available Albumin microspheres (AMS have found many applications in the diagnosis and treatment in recent years and more than 100 diagnostic agents and drugs have been incorporated into AMS. In the present study Bovine Serum Albumin (BSA based microspheres bearing propranolol hydrochloride were prepared by an emulsion-internal phase stabilization technique. The prepared microspheres were studied for particle size distribution, drug loading, release characteristics, bioadhesion and in-vitro controlled diffusion across the rat intestine. The microspheres had mean diameters between 1-25 mm of which more than 50 percent were below 5 mm. The encapsulated drug was found to be about 9% w/w of that initially added to microspheres and the superficial drug was 25% of the total amount of the encapsulated drug. Also AMS were noted to possess good bioadhesion in such a way that about 70% of microspheres remained adherent on the surface mucosa of rat jejunum.The drug release from albumin microspheres was mainly controlled by diffusion and showed a biphasic pattern with a high initial release (burst effect, followed by a more gradual terminal release. The total amount of drug released from microspheres after 12h was 70%. In vitro experiments on the rat intestinal segments revealed that the microspheres could effectively pass their content through intestinal membrane.

  20. Chitosan microspheres in PLG films as devices for cytarabine release.

    Science.gov (United States)

    Blanco, M D; Gómez, C; Olmo, R; Muñiz, E; Teijón, J M

    2000-07-20

    Cytarabine was included in chitosan microspheres and several of these microspheres were embedded in a poly(lactide-co-glycolide) (PLG) film to constitute a comatrix system, to develop a prolonged release form. Chitosan microspheres, in the range of 92+/-65 microm, having good spherical geometry and a smooth surface incorporating cytarabine, were prepared. The cytarabine amount included in chitosan microspheres was 43.7 microg of ara-C per milligram microsphere. The incorporation efficiency of the cytarabine in microspheres was 70.6%. Total cytarabine release from microspheres in vitro was detected at 48 h. Inclusion of cytarabine-loaded microspheres in poly(lactide-co-glycolide) film initiated a slower release of the drug and, in this way, the maximum of cytarabine released (80%) took place in vitro at 94.5 h. Comatrices, with 8.7 mg of cytarabine, signifying a dose of 34.5 microg/kg, were subcutaneously implanted in the back of rats. Maximum plasma cytarabine concentration was 18.5+/-1.5 microg/ml, 48 h after the device implantation and the drug was detected in plasma for 13 days. The histological studies show a slow degradative process. After 6 months of implantation, most of the microspheres of the matrix seemed to be intact, the comatrix appeared surrounded by conjunctive tissue and small blood vessels and nerve packets were detected in the periphery of the implant.

  1. Synthesis of raspberry-like magnetic polystyrene microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Xu Zhizhong [Key Laboratory of Molecular Engineering of Polymers (Ministry of Education), Department of Macromolecular Science, Fudan University, Shanghai 200433 (China); Xia Ao [Key Laboratory of Molecular Engineering of Polymers (Ministry of Education), Department of Macromolecular Science, Fudan University, Shanghai 200433 (China); Wang Changchun [Key Laboratory of Molecular Engineering of Polymers (Ministry of Education), Department of Macromolecular Science, Fudan University, Shanghai 200433 (China)]. E-mail: ccwang@fudan.edu.cn; Yang Wuli [Key Laboratory of Molecular Engineering of Polymers (Ministry of Education), Department of Macromolecular Science, Fudan University, Shanghai 200433 (China); Fu Shoukuang [Key Laboratory of Molecular Engineering of Polymers (Ministry of Education), Department of Macromolecular Science, Fudan University, Shanghai 200433 (China)

    2007-06-15

    Raspberry-like magnetic polystyrene microspheres were prepared via soap-free emulsion polymerization using 2,2'-azobis(2-methylpropionamidine) dihydrochloride (V50) as initiator. The effect of polymerization parameters, such as initiator type, initiator content and the feeding sequence on the particle size and morphology of magnetic polystyrene microspheres, were examined. The final magnetic polystyrene microspheres were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM) and thermogravimetric analysis (TGA). The experimental results showed that V50 was a suitable initiator for preparation of raspberry-like magnetic polystyrene microspheres.

  2. Atypical antipsychotics olanzapine, quetiapine, and risperidone and risk of acute major cardiovascular events in young and middle-aged adults

    DEFF Research Database (Denmark)

    Pasternak, Björn; Svanström, Henrik; Ranthe, Mattis F

    2014-01-01

    risperidone (n = 14,134). The primary outcome was any major cardiovascular event (composite of cardiovascular mortality, acute coronary syndrome, or ischemic stroke) within 1 year following treatment initiation. Cox regression was used to estimate hazard ratios (HRs) while on current antipsychotic monotherapy......BACKGROUND: A number of serious cardiovascular safety concerns related to the use of atypical antipsychotics, compared with no use, have emerged, but nearly all reports are from studies of older patients. We aimed to compare the risk of cardiovascular events between the three most commonly used...... in the outpatient setting, adjusting for an outcome-specific disease risk score. RESULTS: The crude rate of any major cardiovascular event was 5.3 per 1,000 person-years among olanzapine users, 3.4 in quetiapine users, and 5.2 in risperidone users. Compared with risperidone, the risk of any major cardiovascular...

  3. Use of a Direct Observational Measure in a Trial of Risperidone and Parent Training in Children with Pervasive Developmental Disorders.

    Science.gov (United States)

    Handen, Benjamin L; Johnson, Cynthia R; Butter, Eric M; Lecavalier, Luc; Scahill, Lawrence; Aman, Michael G; McDougle, Christopher J; Arnold, L Eugene; Swiezy, Naomi B; Sukhodolsky, Denis G; Mulick, James A; White, Susan W; Bearss, Karen; Hollway, Jill A; Stigler, Kimberly A; Dziura, James; Yu, Sunkyung; Sacco, Kelley; Vitiello, Benedetto

    2013-06-01

    A Structured Observational Analog Procedure (SOAP), an analogue measure of parent-child interactions, was used to assess treatment outcome in children with Autism Spectrum Disorder and serious behavior problems. It served as a secondary outcome measure in a 24-week, randomized trial of risperidone (MED; N=49) versus risperidone plus parent training (COMB; n=75) (ages 4-13 years). At 24-weeks, there was 28 % reduction in child inappropriate behavior during a Demand Condition (p=.0002) and 12 % increase in compliance to parental requests (p=.004) for the two treatment conditions combined. Parents displayed 64 % greater use of positive reinforcement (p=.001) and fewer repeated requests for compliance (ppositive reinforcement (p=.01) and fewer restrictive statements (p<.05) than MED parents. The SOAP is sensitive to change in child and parent behavior as a function of risperidone alone and in combination with PMT and can serve as a valuable complement to parent and clinician-based measures.

  4. Neutron transmission measurements on hydrogen filled microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Dyrnjaja, Eva, E-mail: dyrnjaja@ati.ac.at [Vienna University of Technology, Institute of Atomic and Subatomic Physics, Stadionallee 2, Vienna (Austria); Hummel, Stefan, E-mail: hummel@fotec.at [FOTEC GmbH, Viktor Kaplan-Straße 2, 2700 Wiener Neustadt (Austria); Keding, Marcus, E-mail: keding@fotec.at [FOTEC GmbH, Viktor Kaplan-Straße 2, 2700 Wiener Neustadt (Austria); Smolle, Marie-Theres, E-mail: marie-theres.smolle@tuwien.ac.at [Vienna University of Technology, Institute of Atomic and Subatomic Physics, Stadionallee 2, Vienna (Austria); Gerger, Joachim, E-mail: gerger@fotec.at [FOTEC GmbH, Viktor Kaplan-Straße 2, 2700 Wiener Neustadt (Austria); Zawisky, Michael, E-mail: zawisky@ati.ac.at [Vienna University of Technology, Institute of Atomic and Subatomic Physics, Stadionallee 2, Vienna (Austria)

    2014-01-01

    Hollow microspheres are promising candidates for future hydrogen storage technologies. Although the physical process for hydrogen diffusion through glass is well understood, measurements of static quantities (e.q. hydrogen pressure inside the spheres) as well as dynamic properties (e.g. diffusion rate of hydrogen through glass) are still difficult to handle due to the small size of the spheres (d≈15μm). For diffusion rate measurements, the long-term stability of the experiment is also mandatory due to the relatively slow diffusion rate. In this work, we present an accurate and long-term stable measurement technique for static and dynamic properties, using neutron radiography. Furthermore, possible applications for hydrogen filled microspheres within the scope of radiation issues are discussed.

  5. Optical Microspherical Resonators for Biomedical Sensing

    Directory of Open Access Journals (Sweden)

    Giancarlo C. Righini

    2011-01-01

    Full Text Available Optical resonators play an ubiquitous role in modern optics. A particular class of optical resonators is constituted by spherical dielectric structures, where optical rays are total internal reflected. Due to minimal reflection losses and to potentially very low material absorption, these guided modes, known as whispering gallery modes, can confer the resonator an exceptionally high quality factor Q, leading to high energy density, narrow resonant-wavelength lines and a lengthy cavity ringdown. These attractive characteristics make these miniaturized optical resonators especially suited as laser cavities and resonant filters, but also as very sensitive sensors. First, a brief analysis is presented of the characteristics of microspherical resonators, of their fabrication methods, and of the light coupling techniques. Then, we attempt to overview some of the recent advances in the development of microspherical biosensors, underlining a number of important applications in the biomedical field.

  6. Aptamer Based Microsphere Biosensor for Thrombin Detection

    Directory of Open Access Journals (Sweden)

    Xudong Fan

    2006-08-01

    Full Text Available We have developed an optical microsphere resonator biosensor using aptamer asreceptor for the measurement of the important biomolecule thrombin. The sphere surface ismodified with anti-thrombin aptamer, which has excellent binding affinity and selectivityfor thrombin. Binding of the thrombin at the sphere surface is monitored by the spectralposition of the microsphere’s whispering gallery mode resonances. A detection limit on theorder of 1 NIH Unit/mL is demonstrated. Control experiments with non-aptameroligonucleotide and BSA are also carried out to confirm the specific binding betweenaptamer and thrombin. We expect that this demonstration will lead to the development ofhighly sensitive biomarker sensors based on aptamer with lower cost and higher throughputthan current technology.

  7. Risperidone regulates Dopamine D2-like receptors expression in rat brain in a time-dependent manner

    Directory of Open Access Journals (Sweden)

    Ni Peiyan

    2015-03-01

    Full Text Available Background and Objectives: Antipsychotics can elicit dopamine super-sensitivity by up-regulation of D2-like receptors (DRD2, DRD3, and DRD4 expression. Nevertheless, the expression profile of dopamine D2-like receptors in different brain regions and peripheral blood mononuclear cells (PBMCs, and changes following risperidone administration were still unclear. In this study, we would investigate the expression of D2-like receptors mRNA in different brain regions and the peripheral blood mononuclear cells (PBMCs in rats after 2, 6 weeks risperidone administration. Methods: The experimental rats were given risperidone (0.25mg/kg/day, i.p., and the control rats were given 0.9% NaCl. The rats were sacrificed at 0 week, 2 weeks and 6 weeks after the drug administration. Expression of the dopamine D2-like receptors was quantified by Real-time PCR method. Results: Dopamine D2-like receptors expressed in all the examined regions of rat brain. Their expression significantly increased 2weeks after risperidone administration in different brain regions. However, the changed expression of DRD2 and DRD3 turned back to the basal level 6weeks later, while the increased DRD4 expression remained in left parietal cortex. Meanwhile, DRD2 and DRD3 but not DRD4 expressed in PBMCs, however, the risperidone could not affect their expression. Conclusions: The risperidone could change the dopamine D2-like receptors expression in a time-dependent manner in different brain regions, which might guide the clinical use in the near future.

  8. Risperidone use in a teaching hospital during its first year after market approval: economic and clinical implications.

    Science.gov (United States)

    Carter, C S; Mulsant, B H; Sweet, R A; Maxwell, R A; Coley, K; Ganguli, R; Branch, R

    1995-01-01

    Risperidone, a new antipsychotic drug, was recently approved by the Food and Drug Administration (FDA) on the basis of its having comparable efficacy and less toxicity than haloperidol. In a preliminary study to evaluate the therapeutic efficiency of this drug, we conducted a survey of resperidone utilization, cost, and safety during its first year of availability at an academic psychiatric hospital. Data were obtained from a computerized, centralized medical record system, from an adverse drug reaction monitoring system, and from pharmacy purchasing records. In its first year of availability, risperidone became the second most widely used antipsychotic agent at our institution. Most of this use extended beyond the adult schizophrenia population, for whom pre-marketing safety and efficacy data are available. The direct institutional cost of risperidone treatment exceeded the entire budget for antipsychotic drugs during the year before its release. Results from the adverse drug reaction reporting system did not indicate a strong advantage of risperidone over more established antipsychotic agents with respect to extrapyramidal side effects. Furthermore, the mean dose of risperidone associated with extrapyramidal symptoms was 3.5 mg/day, considerably lower than that suggested by pre-marketing studies in a more select patient group. These results confirm that new pharmacological agents are generally used in much broader patient populations than those for which efficacy and safety have been established prior to FDA approval. This study also raises questions about the therapeutic efficiency of risperidone compared with other antipsychotic drugs. We conclude that systematic studies of outcome, safety, and cost of new pharmaceuticals in naturalistic settings are needed to provide the data necessary to establish local standards of cost-effective care.

  9. Effects of lactational exposure of olanzapine and risperidone on hematology and lymphoid organs histopathology: a comparative study in mice neonates.

    Science.gov (United States)

    Mishra, Akash C; Mohanty, Banalata

    2010-05-25

    Body weight gain, sexual/reproductive dysfunction and hematological abnormalities are serious consequences of atypical antipsychotics treatment. No attempts however have been made preclinically to elucidate the adverse hematological impacts. Presently, effects of lactational exposure of olanzapine (4, 8 and 10 mg/kg) and risperidone (1 and 2 mg/kg) on hematology as well as lymphoid organ histopathology of mice neonates were investigated. Both olanzapine and risperidone transfers through milk and make the neonates susceptible to their adverse side effects. Corticosterone elevation tendency of both the drugs further enhance the susceptibility for immune dysfunction. Analysis of total and differential leukocytes counts revealed neutropenia with all the doses of olanzapine but only with risperidone 2mg/kg. Weight analysis and histopathology of thymus and spleen indicated a state of suppression; less in the risperidone-exposed groups. Significant plasma corticosterone elevation occurred on 4 and 8 mg/kg olanzapine exposures but not with 10 mg/kg as well as with both the risperidone doses. Elevation of plasma prolactin levels occurred dose-dependently for both the drugs. Hematological toxicity (neutropenia) might be the direct toxic effects of the drugs/unstable metabolites on circulating neutrophils and/or on the bone marrow hemopoietic cells. Direct toxicity of the drugs might also have suppressed the lymphoid organs thymus and spleen. Further, it could be associated to hormonal imbalance induced by adverse pharmacological effects of the drugs on the endocrine system. Suppression of lymphoid organs in olanzapine groups might have resulted because of corticosteronemia and hyperprolactinemia, while in risperidone it could be mediated by pronounced hyperprolactinemic effect alone.

  10. Choline acetyltransferase expression in rat prefrontal cortex and hippocampus after acute and chronic exposure to amisulpride, haloperidol, and risperidone.

    Science.gov (United States)

    Huang, Guang-Biao; Zhao, Tong; Li, Chun-Rong; Sui, Zhi-Yan; Kang, Nam-In; Han, Eui-Hyeog; Chung, Young-Chul

    2012-10-24

    Recently, there has been an increasing concern that atypical antipsychotics as well as typical ones may cause detrimental effects on cognitive function. Supporting evidence comes from many preclinical studies demonstrating that long-term administration of haloperidol, risperidone, and ziprasidone reduced choline acetyltransferase (ChAT) expression in rat hippocampus (HIP). However, to the best of our knowledge, no studies have examined the effects of amisulpride on ChAT expression in rats. Therefore, the aim of this study was to investigate the effects of acute and chronic administration of amisulpride, haloperidol, and risperidone on ChAT expression in the rat prefrontal cortex (PFC) and HIP. Animals received daily intraperitoneal (i.p.) injections of amisulpride (5 or 100mg/kg), haloperidol (1 or 2mg/kg), risperidone (1 or 2mg/kg) or vehicle for 7 or 45 days. One day after the last injection, rats were sacrificed. ChAT immunoreactivity was assessed with immunofluorescence staining. Target areas of brain were PFC and HIP (CA1, CA3 and DG). The short-term administration of haloperidol and risperidone produced significant decrease of ChAT immunoreactivity in the PFC and HIP compared to vehicle whereas amisulpride had no effects on ChAT immunoreactivity in the PFC and HIP. In long-term study, haloperidol and risperidone decreased ChAT-positive cells and/or fiber pixel density in the PFC and HIP whereas amisulpride decreased ChAT-positive cells in the PFC and had no effects on fiber pixel density of ChAT in the HIP. The results suggest that both short-term and long-term administration of haloperidol and risperidone, and long-term administration of amisulpride may produce detrimental effects on cognitive function by reducing ChAT expression in the PFC and/or HIP.

  11. Comparative study of the efficacy and safety between blonanserin and risperidone for the treatment of schizophrenia in Chinese patients: A double-blind, parallel-group multicenter randomized trial.

    Science.gov (United States)

    Li, Huafang; Yao, Chen; Shi, Jianguo; Yang, Fude; Qi, Shuguang; Wang, Lili; Zhang, Honggeng; Li, Jie; Wang, Chuanyue; Wang, Chuansheng; Liu, Cui; Li, Lehua; Wang, Qiang; Li, Keqing; Luo, Xiaoyan; Gu, Niufan

    2015-10-01

    This randomized, double-blind study compared the efficacy and safety of blonanserin and risperidone to treat Chinese schizophrenia patients aged ≥18 and blonanserin or risperidone using a gradual dose-titration method (blonanserin tablets: 8-24 mg/day; risperidone tablets: 2-6 mg/day), twice daily. Treatment populations consisted of 128 blonanserin-treated patients and 133 risperidone-treated patients. Intention-to-treat analysis was performed using the last observation carried forward method. Reductions of PANSS total scores by blonanserin and risperidone treatment were -30.59 and -33.56, respectively. Risperidone treatment was associated with elevated levels of serum prolactin (67.16% risperidone versus 52.31% blonanserin) and cardiac-related abnormalities (22.39% risperidone versus 12.31% blonanserin), and blonanserin patients were more prone to extrapyramidal side effects (48.46% blonanserin versus 29.10% risperidone). In conclusion, blonanserin was as effective as risperidone for the treatment of Chinese patients with schizophrenia. The overall safety profiles of these drugs are comparable, although blonanserin was associated with a higher incidence of EPS and risperidone was associated with a higher incidence of prolactin elevation and weight gain. Thus, blonanserin is useful for the treatment of Chinese schizophrenia patients. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Sputter coating of microspherical substrates by levitation

    Science.gov (United States)

    Lowe, A.T.; Hosford, C.D.

    Microspheres are substantially uniformly coated with metals or nonmetals by simltaneously levitating them and sputter coating them at total chamber pressures less than 1 torr. A collimated hole structure comprising a parallel array of upwardly projecting individual gas outlets is machined out to form a dimple. Glass microballoons,, which are particularly useful in laser fusion applications, can be substantially uniformly coated using the coating method and apparatus.

  13. An open-label, multicenter evaluation of the long-term safety and efficacy of risperidone in adolescents with schizophrenia

    Directory of Open Access Journals (Sweden)

    Pandina Gahan

    2012-06-01

    Full Text Available Abstract Background Data on the long-term efficacy, safety, and tolerability of risperidone in adolescents with schizophrenia are limited. The objective of this study was to evaluate the efficacy and safety of maintenance risperidone treatment in adolescents with schizophrenia. Methods This open-label study of adolescents aged 13 to 17 years with schizophrenia was a single extension study of two short-term double-blind risperidone studies and also enrolled subjects directly in open-label risperidone treatment. The risperidone dose was flexible and ranged from 2 to 6 mg/day. Most subjects enrolled for 6 months; a subset enrolled for 12 months. Assessment tools included the Positive and Negative Syndrome Scale total and factor scores, Clinical Global Impressions, Children’s Global Assessment Scale, adverse event (AE monitoring, vital signs, laboratory testing, and extrapyramidal symptom rating scales. Results A total of 390 subjects were enrolled; 48 subjects had received placebo in a previous double-blind study; 292 subjects had received risperidone as part of their participation in one of two previous controlled studies; and 50 subjects were enrolled directly for this study. A total of 279 subjects enrolled for 6 months of treatment, and 111 subjects enrolled for 12 months of treatment. Overall, 264 (67.7% subjects completed this study: 209 of the 279 subjects (75% in the 6-month group and 55 of the 111 subjects (50% in the 12-month group. The median mode dose was 3.8 mg/day. At 6 months, all three groups experienced improvement from open-label baseline in symptoms of schizophrenia as well as general assessments of global functioning. Improvements were generally maintained for the duration of treatment. The most common AEs (≥10% of subjects were somnolence, headache, weight increase, hypertonia, insomnia, tremor, and psychosis. Potentially prolactin-related AEs (PPAEs were reported by 36 (9% subjects. The AE profile in this study was

  14. Effect of acute and chronic treatment with risperidone on the serotonin and dopamine receptors in the rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yun Young; Moon, Dae Hyuk; Son, Hye Kyung; Kim, Chang Yoon; Lee, Chul; Lee, Hee Kyung [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of)

    1997-03-01

    The therapeutic efficacy of antipsychotic drugs is generally attributed to their ability to block dopamine D{sub 2} receptors. Classical D{sub 2} antagonists are not effective to treat negative symptoms and produce extrapyramidal side effects. On the other hand, atypical antipsychotic agents ameliorate negative symptoms without producing extrapyramidal side effects, and it is reported to be associated with blockade of serotonin 5-HT{sub 2} receptors. The purpose of this study was to evaluate the effect of risperidone on neuroreceptors in the rat brain by quantitative autoradiography method. In acute treatment group, risperidone was injected into peritoneal cavity of male Wistar rats with dose of 0, 0.1, 0.25, 0.5, 1.0 and 2.0mg/kg in each group (5/group), and they were decapitated after 2 hours. In chronic treatment group, risperidone was injected with dose of 0, 0.1, and 1m/kg (I.P.) for 21 ays and decapitated after 24 hours following last treatment. The effect of risperodone on the binding of [{sup 3}H) spiperone to 5-HT{sub 2} and D{sub 2} receptors were analysed in 4 discrete regions of the striatum, nucleus accumbens, and frontal cortex by quantitative autoradiography. Acute treatment with risperidone reduced cortical 5-HT{sub 2} specific [{sup 3}H]spiperone binding to 32% of vehicle-treated control. Subcortical 5-HR{sub 2} specific [{sup 3}H]spiperone binding was not affected at all dose groups whereas a significant reduction (57%) in D{sub 2} specific [{sup 3}H]spiperone binding was observed in risperidone treated group at doses of 1-2mg/kg. Chronic treatment with risperidone produced a decrease in the maximal number of cortical 5-HT{sub 2} receptors to 51% and 46% of control in 0.1mg/kg and 1mg/kg treated group respectively. In conclusion, risperidone is a cortical serotonin receptor antagonist with relatively weak antagonistic action on dopamine receptors. These effects on neuroreceptors may explain the therapeutic effect of risperidone as a atypical

  15. Yttrium-90 microsphere induced gastrointestinal tract ulceration

    Directory of Open Access Journals (Sweden)

    Rikabi Ali A

    2008-09-01

    Full Text Available Abstract Background Radiomicrosphere therapy (RT utilizing yttrium-90 (90Y microspheres has been shown to be an effective regional treatment for primary and secondary hepatic malignancies. We sought to determine a large academic institution's experience regarding the extent and frequency of gastrointestinal complications. Methods Between 2004 and 2007, 27 patients underwent RT for primary or secondary hepatic malignancies. Charts were subsequently reviewed to determine the incidence and severity of GI ulceration. Results Three patients presented with gastrointestinal bleeding and underwent upper endoscopy. Review of the pretreatment angiograms showed normal vascular anatomy in one patient, sclerosed hepatic vasculature in a patient who had undergone prior chemoembolization in a second, and an aberrant left hepatic artery in a third. None had undergone prophylactic gastroduodenal artery embolization. Endoscopic findings included erythema, mucosal erosions, and large gastric ulcers. Microspheres were visible on endoscopic biopsy. In two patients, gastric ulcers were persistent at the time of repeat endoscopy 1–4 months later despite proton pump inhibitor therapy. One elderly patient who refused surgical intervention died from recurrent hemorrhage. Conclusion Gastrointestinal ulceration is a known yet rarely reported complication of 90Y microsphere embolization with potentially life-threatening consequences. Once diagnosed, refractory ulcers should be considered for aggressive surgical management.

  16. Unstirred Water Layer Effects on Biodegradable Microspheres

    Directory of Open Access Journals (Sweden)

    Susan D’Souza

    2015-01-01

    Full Text Available This study explores the mechanistic aspects of in vitro release from biodegradable microspheres with the objective of understanding the effect of the unstirred water layer on polymer degradation and drug release. In vitro drug release experiments on Leuprolide PLGA microspheres were performed under “static” and “continuous” agitation conditions using the “sample and separate” method. At specified time intervals, polymer degradation, mass loss, and drug release were assessed. While molecular weight and molecular number profiles for “static” and “continuous” samples were indistinct, mass loss occurred at a faster rate in “continuous” samples than under “static” conditions. In vitro results describe a fourfold difference in drug release rates between the “continuous” and “static” samples, ascribed to the acceleration of various processes governing release, including elimination of the boundary layer. The findings were confirmed by the fourfold increase in drug release rate when “static” samples were subjected to “continuous” agitation after 11 days. A schema was proposed to describe the complex in vitro release process from biodegradable polymer-drug dosage forms. These experiments highlight the manner in which the unstirred water layer influences drug release from biodegradable microspheres and stress the importance of selecting appropriate conditions for agitation during an in vitro release study.

  17. STRUCTURING OF DIAMOND FILMS USING MICROSPHERE LITHOGRAPHY

    Directory of Open Access Journals (Sweden)

    Mária Domonkos

    2014-10-01

    Full Text Available In this study, the structuring of micro- and nanocrystalline diamond thin films is demonstrated. The structuring of the diamond films is performed using the technique of microsphere lithography followed by reactive ion etching. Specifically, this paper presents a four-step fabrication process: diamond deposition (microwave plasma assisted chemical vapor deposition, mask preparation (by the standard Langmuir-Blodgett method, mask modification and diamond etching. A self-assembled monolayer of monodisperse polystyrene (PS microspheres with close-packed ordering is used as the primary template. Then the PS microspheres and the diamond films are processed in capacitively coupled radiofrequency plasma  using different plasma chemistries. This fabrication method illustrates the preparation of large arrays of periodic and homogeneous hillock-like structures. The surface morphology of processed diamond films is characterized by scanning electron microscopy and atomic force microscope. The potential applications of such diamond structures in various fields of nanotechnology are also briefly discussed.

  18. STUDIES AND EVALUATION OF COMPRESSED MICROSPHERES

    Directory of Open Access Journals (Sweden)

    Idris Mohamed El-Mahdi

    2016-05-01

    Full Text Available This work was aimed at the use of dissolution testing and similarity factor to assess the level of damage taken by active drug microspheres during compression in tablet dosage form. To achieve that, combinations of suitable excipients were used to protect drug microspheres during compression. The excipients were used in the form of powders, granules or placebo pellets prepared by extrusion-spheronization technology. The excipients were evaluated alone, in combinations and post-compression into compacts.  Preliminary experiments included density, hardness, friability and disintegration on all of the selected excipients. Based on such experiments it was found that the flowability of combination powders was more acceptable than individual excipients. Two combinations of microcrystalline -starch and microcrystalline cellulose -calcium carbonate granules were selected to be compressed with active ketoprofen pellets. In all the combinations used there was a significant amount of damage to drug pellets.  The kinetics of drug release appears to follow the zero-order rate and the rate remained unchanged even when a significant degree of damage to pellets occur. It was found that a high level of excipients is required in order to prepare microspheres as a rapid disintegrating tablet. Citation DOI: 10.21502/limuj.002.01.2016  LIMUJ is licensed under a Creative Commons Attribution 4.0 International License

  19. Custom-Made Microspheres for Optical Tweezers.

    Science.gov (United States)

    Jannasch, Anita; Abdosamadi, Mohammad K; Ramaiya, Avin; De, Suman; Ferro, Valentina; Sonnberger, Aaron; Schäffer, Erik

    2017-01-01

    Due to their high position and force sensitivity and the ability to remotely apply forces and torques, optical tweezers are widely used in diverse fields, such as biology, material science, and physics. Often, small dielectric particles are trapped and used as probes, which for experimental convenience are mostly spherical and composed of silica or polystyrene. The optical properties of these materials together with the microsphere size determine the trapping efficiency, and the position and force resolution. However, using only a single, homogeneous, isotropic, and unstructured material limits the range of trapping properties and thereby the applications of optical tweezers. Here, we show how custom-made microspheres composed of coated high-refractive-index materials-titania and nanodiamonds-and birefringent, liquid crystals extend the range and combination of desired trapping properties. These custom-made microspheres either enable the generation of high forces, a high force or time resolution, or the applications of torques. Custom-made probes expand the range of possible experiments and approaches broadening the scope and applicability of optical tweezers.

  20. Optimization of sustained release aceclofenac microspheres using response surface methodology.

    Science.gov (United States)

    Deshmukh, Rameshwar K; Naik, Jitendra B

    2015-03-01

    Polymeric microspheres containing aceclofenac were prepared by single emulsion (oil-in-water) solvent evaporation method using response surface methodology (RSM). Microspheres were prepared by changing formulation variables such as the amount of Eudragit® RS100 and the amount of polyvinyl alcohol (PVA) by statistical experimental design in order to enhance the encapsulation efficiency (E.E.) of the microspheres. The resultant microspheres were evaluated for their size, morphology, E.E., and in vitro drug release. The amount of Eudragit® RS100 and the amount of PVA were found to be significant factors respectively for determining the E.E. of the microspheres. A linear mathematical model equation fitted to the data was used to predict the E.E. in the optimal region. Optimized formulation of microspheres was prepared using optimal process variables setting in order to evaluate the optimization capability of the models generated according to IV-optimal design. The microspheres showed high E.E. (74.14±0.015% to 85.34±0.011%) and suitably sustained drug release (minimum; 40% to 60%; maximum) over a period of 12h. The optimized microspheres formulation showed E.E. of 84.87±0.005 with small error value (1.39). The low magnitudes of error and the significant value of R(2) in the present investigation prove the high prognostic ability of the design. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) revealed the dispersion of drug within microspheres formulation. The microspheres were found to be discrete, spherical with smooth surface. The results demonstrate that these microspheres could be promising delivery system to sustain the drug release and improve the E.E. thus prolong drug action and achieve the highest healing effect with minimal gastrointestinal side effects.

  1. Gabapentin adjunctive to risperidone or olanzapine in partially responsive schizophrenia: an open-label pilot study

    Directory of Open Access Journals (Sweden)

    Adel Gabriel

    2010-10-01

    Full Text Available Adel GabrielDepartments of Psychiatry and Community Health Sciences, University of Calgary, Alberta, CanadaBackground: There is a great need in the treatment of schizophrenia for a drug, or drug ­combinations, to improve clinical response with fewer serious side effects. The objective of this study was to explore the therapeutic effects and tolerability of the anticonvulsant gabapentin as an adjunctive in the treatment of patients with partially responsive schizophrenia.Methods: Ten consenting patients with a confirmed Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision diagnosis of schizophrenia were identified. All patients failed at least one 12-week treatment trial with risperidone or olanzapine. Gabapentin was added to ongoing antipsychotic treatment with olanzapine or risperidone for eight weeks. The primary outcome measure was the Positive and Negative Syndrome Scale (PANSS. Other scales included the Calgary Depression Scale (CDSS and the Abnormal Involuntary Movement Scale (AIMS. Repeated-measures multivariate analysis of variance was utilized to examine changes in outcome measures over time with adjunctive treatment with gabapentin.Results: There was a significant drop in the PANSS and CDSS scores at endpoint (week 8. There were no significant differences between the two treatment groups with regard to changes in all outcome measures or in AIMS score. The adjunctive treatments were well tolerated and side effects were transient.Conclusion: Gabapentin could be used successfully as an adjunct to novel antipsychotics in partially responsive schizophrenia. However, large controlled studies are needed to examine the effectiveness of gabapentin in psychotic disorders.Keywords: schizophrenia, refractory, adjunctive treatment, gabapentin, risperidone, olanzapine

  2. Report of a Rare Case of Olanzapine and Risperidone Induced Hypomania

    Directory of Open Access Journals (Sweden)

    AR Zahiroddin

    2006-07-01

    Full Text Available Introduction & Objective: Hypomania is a mood disorder with symptoms of constantly high expansive or irritable mood. After a 4-day period, the patient feels to be in need of less sleep, being talkative, or feeling pressure if not treated kindly, having flight of ideas, distractibility, and increase in goal oriented activities (including social, occupational, educational or sexual activities and being extravagant. Hypomania could be a mood episode of bipolar I and II mood disorder or cyclothymia and could be resulted from consumption of drugs, materials, Electro Convulsive Therapy (ECT or photo therapy. Case: The present report is the case of a 57-year old married woman, who has had a record of bipolar I mood disorder since 30 years ago. The patient was hospitalized once in psychiatry hospital and referred to psychiatry office 2 years ago. She has been under medication therapy by lithium 600 mg, nortriptyline 75 mg, and colonazpam 1 mg. She has taken risperidone 2 mg, the symptoms of hypomania have revealed. After stopping the consumption of risperidone, the treatment continued by lithium tablet 900 mg, eskazina tablet 4 mg, nortriptyline 75 mg for one day. She was under care for 15 months and then due to muscle complications of lithium, pessimism, auditory and visual hallucination, she was recommended to take olanzapine tablet 5 mg once every night. Two days after taking olanzapine the symptoms of hypomania revealed. Consumption of olanzapine was then stopped and the symptoms disappeared and she was brought under control after taking sodiumvalproate tablet. Conclusion: Rarely could Hypomania be a mood episode induced by consuming atypical antipsychotics such as risperidone and olanzapine.

  3. Evaluation of teratogenic effects of risperidone following simultaneous administration with antihypertensive and antiemetic drugs.

    Science.gov (United States)

    Tauqeer, Shaista; Khan, Rafeeq Alam; Siddiqui, Afaq Ahmed

    2012-01-01

    Multiple drug administration is an important aspect of clinical practice particularly in specific physiological situation such as in neonates, elderly or pregnancy, since in all such situations, possibility of unwanted effects increases due to altered body physiology. In present study, the teratogenic effects of multiple drug administration risperidone, meclizine/pyridoxine and hydralazine have been compared with the teratogenic effects of individual drugs in pregnant mice. Moreover the role of folic acid and α-tocopherol if any had also been investigated in reducing the teratogenic effects of these drugs in combinations.

  4. Efficacy of ziprasidone and risperidone in treatment of vagrants with schizophrenia

    Institute of Scientific and Technical Information of China (English)

    Zhan-Hua Li; Zhi-Xiang Li

    2016-01-01

    Objective:To explore the clinical efficacy of ziprasidone and risperidone in the treatment of vagrants with schizophrenia.Methods:A total of 70 vagrants with schizophrenia who were admitted in our hospital from December, 2014 to December, 2015 were included in the study and divided into the observation group (ziprasidone) and the control group (risperidone) according to different treatment protocols. In the observation group, the initial dosage of ziprasidone was 20 mg/d, and was gradually increased to 80-160 mg/d within 10 d, with an average dosage of (105.6±38.7) mg/d. In the control group, the initial dosage of risperidone was 1 mg/d, and was gradually increased to 3-5 mg/d within 10 d, with an average dosage of (3.6±0.9) mg/d. Eight-week treatment was regarded as one course. PANSS was used for grading before and after treatment. The levels of FBG, TG, TC, and HDL-C before and after treatment were detected. The adverse reactions after treatment were observed.Results:With the extending of treatment time, PANSS positive symptoms, negative symptoms, psychosis symptoms, and total scores in the two groups were significantly reduced when compared with before treatment (P0.05). After treatment, the levels of FBG, TG, TC, and HDL-C in the observation group were not significantly different from those before treatment (P>0.05), while those levels in the control group were significantly elevated when compared with before treatment (P<0.05), and those in the observation group were significantly superior to those in the control group (P<0.05). After treatment, the occurrence rate of adverse reactions in the observation was significantly lower than that in the control group (P<0.05).Conclusions: The clinical efficacy of ziprasidone and risperidone in the treatment of vagrants with schizophrenia is equal, but ziprasidone has a small effect on the blood sugar and lipid, with less adverse reactions and preferable compliance; therefore, it deserves to be widely recommended in

  5. Bioequivalence study of a generic Risperidone (Iperdal® in healthy Thai male volunteers

    Directory of Open Access Journals (Sweden)

    Werawath Mahatthanatrakul

    2008-05-01

    Full Text Available The objective of this study was to compare the rate and extent of absorption of a generic risperidone (Iperdal® with a reference formulation (Risperdal® when given orally. The study was an open label, randomized, two-period, two-sequence,single dose cross-over design with a 2 weeks washout period in 16 healthy Thai male volunteers. Single oral dose of two 2-mg tablets of risperidone were administered and serial blood samples were collected from the antecubital vein before and at0.17, 0.33, 0.5, 0.75, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0, 8.0, 12, 24 and 48 hours post dose. Risperidone plasma concentrations were assayed using a validated High Performance Liquid Chromatographic (HPLC-UV method modified from Avenosoet al. (2000. Pharamcokinetic parameters i.e. Cmax, AUC0à48 and Tmax were analyzed by noncompartment analysis. Variations of the data were analyzed by “Two Way Analysis of Variance” (ANOVA. Statistics were tested as stated in USP 28 guidelinefor bioequivalence study. The maximum concentration (Cmax, ng/ml of risperidone for the innovator and the generic product were 31.11±17.24 (range 5.64-56.78 and 32.58±19.77 (range 5.29-84.56 ng/ml, respectively. The area under theplasma concentration-time curve (AUC0®48 of the innovator and the generic product were 160.64±152.89 (range 18.57- 550.32 and 144.03±127.37 (range 16.27-456.0 ng.hr/ml, respectively. The time to maximum concentration (Tmax of theinnovator and the generic product were 0.97±0.41(range 0.5-2 and 1.02±0.32 (range 0.5-1.5 hr, respectively. The 90% confidence interval of the ratio of the ln-transformed of Cmax and AUC0à48 of both preparations were 89.39-112.99% and80.02-107.28% respectively which were within the acceptance range of 80.00-125.00%. Therefore, it can be concluded that both preparations used in this study are bioequivalent in terms of both the rate and extent of absorption.

  6. Deep vein thrombosis associated with long-term use of risperidone

    Directory of Open Access Journals (Sweden)

    Kuldeep Singh Yadav

    2016-01-01

    Full Text Available There are increasing number of deep vein thrombosis (DVT cases that are associated with the use of atypical antipsychotics. We are presenting a case report of a female patient who suffered from DVT. She was a known case of schizophrenia and was on risperidone 4 mg for the last 5 years. She had good physical health before that and there were no known risk factors for DVT. The family history of DVT was also found to be negative. She was managed by intravenous heparin followed by oral warfarin and amisulpride 100 mg/day. Atypical antipsychotics can induce DVT, and psychiatrist should be careful about it.

  7. MAGNETIC MICROSPHERES: A LATEST APPROACH IN NOVEL DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Mukherjee S

    2012-10-01

    Full Text Available Magnetic microspheres are at the forefront of the rapidly developing field of pharmaceutical technology with several potential applications in drug delivery, clinical medicine and research as well as in other varied sciences. Due to their unique size-dependent properties, magnetic microspheres offer the possibility to develop new therapeutics. The ability to incorporate drugs into carriers offers a new prototype in drug delivery that could be used for secondary and tertiary levels of drug targeting. Hence, magnetic microspheres hold great promise for reaching the goal of controlled and site specific drug delivery and hence have attracted wide attention of researchers. This review presents a broad treatment of magnetic microspheres discussing their advantages, limitations and their possible remedies. Different production methods which are suitable for large scale production and applications of magnetic microspheres are described. Appropriate analytical techniques for characterization of magnetic microspheres like Photon correlation spectroscopy, scanning electron microscopy, differential scanning calorimetry are highlighted. Aspects of magnetic microspheres route of administration and their biodistribution are also incorporated. If appropriately investigated, magnetic microspheres may open new vistas in therapy of complex diseases.

  8. Microspheres with Ultrahigh Holmium Content for Radioablation of Malignancies

    NARCIS (Netherlands)

    Bult, W.; Seevinck, P.R.; Krijger, G.C.; Visser, T.; Kroon-Batenburg, L.M.J.; Bakker, C.J.G.; Hennink, W.E.; Van het Schip, A.D.; Nijsen, J.F.W.

    Purpose The aim of this study was to develop microspheres with an ultra high holmium content which can be neutron activated for radioablation of malignancies. These microspheres are proposed to be delivered selectively through either intratumoral injections into solid tumors or administered via an

  9. Microspheres with ultrahigh holmium content for radioablation of malignancies

    NARCIS (Netherlands)

    Bult, W; Seevinck, P R; Krijger, G C; Visser, T; Kroon-Batenburg, L M J; Bakker, C J G; Hennink, W E; van het Schip, A D; Nijsen, J F W

    2009-01-01

    PURPOSE: The aim of this study was to develop microspheres with an ultra high holmium content which can be neutron activated for radioablation of malignancies. These microspheres are proposed to be delivered selectively through either intratumoral injections into solid tumors or administered via an

  10. Preparation and characterization of albumin-heparin microspheres

    NARCIS (Netherlands)

    Cremers, H.F.M.; Kwon, G.; Bae, Y.H.; Kim, S.W.; Verrijk, R.; Noteborn, H.P.J.M.; Feijen, J.

    1994-01-01

    Albumin-heparin microspheres were prepared by a two-step process which involved the preparation of a soluble albumin-heparin conjugate, followed by formation of microspheres from this conjugate or by a double cross-linking technique involving both coupling of soluble albumin and heparin and microsph

  11. Pectin/zein microspheres as a sustained drug delivery system

    Science.gov (United States)

    A series of microspheres were prepared from pectins and corn proteins from various sources in the presence of the divalent ions calcium or zinc. The results showed that the yield of microsphere and the efficiency of drug incorporation were dependent on the type and ratio of biopolymers, the size of ...

  12. Porous-wall hollow glass microspheres as carriers for biomolecules

    Science.gov (United States)

    Li, Shuyi; Dynan, William S; Wicks, George; Serkiz, Steven

    2013-09-17

    The present invention includes compositions of porous-wall hollow glass microspheres and one or more biomolecules, wherein the one or more biomolecules are positioned within a void location within the hollow glass microsphere, and the use of such compositions for the diagnostic and/or therapeutic delivery of biomolecules.

  13. PREPARATION AND ADSORBABILITY OF DEXTRAN MICROSPHERES WITH UNIFORM DIAMETER

    Institute of Scientific and Technical Information of China (English)

    Ri-sheng Yao; Wen-xia Gao; Jing Sun; Ya-hua You

    2005-01-01

    The method of preparing uniform dextran microspheres with a narrow diameter distribution was introduced and the adsorbability of these microspheres was evaluated. The microspheres were prepared in W/O microemulsion using 0.5% dextran solution as the aqueous phase and n-hexane as the oil phase. Characteristics of the prepared dextran microspheres were examined with laser light blocking technique, optical microscope and ultraviolet spectrometer. The results show that the prepared dextran microspheres have uniform morphology and narrow diameter distribution, nearly 92% of them having a diameter of 56.6 μm. In vitro evaluation of adsorbability, wet dextran microspheres have good adsorption of 98.32 mg/g of model drug methylene blue in 20.86 mg/L methylene blue solution at 25℃. The adsorption of dried dextran microspheres under the same condition is 132.15 mg/g, which is even higher. And the adsorbability of dextran microspheres has significant relationship with the concentration of methylene blue and temperature. The adsorbability is better at lower temperature and higher concentration of methylene blue.

  14. Design and Fabrication of Superparamaganitic Hybrid Microspheres for Protein Immobilization

    Institute of Scientific and Technical Information of China (English)

    REN Qi; CHU Hong; CHEN Mingqing; NI Zhongbin; CHEN Qiuyun

    2011-01-01

    Superparamagnetic poly(styrene)-co-poly(2-acrylanmido-2-methyl propanesulfonic acid) (PStco-PAMPS) and poly(methylmethacrylate)-co-poly(glycidyl methacrylate) (PMMA-co-PGMA) microspheres with mean size of 170 nm were prepared by emulsion polymerization in the presence of oleic acid-coated Fe3O4 nanoparticles.The structures,morphologies,diameter and diameter distribution of the as-prepared microspheres were identified by Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM).The saturation magnetizations of PSt-co-PAMPS and PMMA-co-PGMA microspheres are 21.94 and 25.07emu/g,respectively.The as-synthesized magnetic microspheres were used for immobilization of Bovine serum albumin (BSA) by physical interaction and covalent interaction respectively.The equilibrium amount of BSA immobilized onto PMMA-co-PGMA microspheres was 86.48 mg/g microspheres in 90 min,while on PSt-coPAMPS microspheres was 59.62 mg/g microspheres in 120 min.

  15. Antibacterial activity of ciprofloxacin-loaded zein microsphere films

    Energy Technology Data Exchange (ETDEWEB)

    Fu Jianxi [Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032 (China); Henan Normal University, 46 East Construction Road, Xinxiang, Henan 453007 (China); Wang Huajie [College of Life Science and Biotechnology, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030 (China); Zhou Yanqing [Henan Normal University, 46 East Construction Road, Xinxiang, Henan 453007 (China); Wang Jinye, E-mail: jywang@mail.sioc.ac.cn [Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032 (China); College of Life Science and Biotechnology, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030 (China)

    2009-05-05

    Our aim was to produce an antibiotic-emitting coating composed of zein microspheres for the prevention of bacterial infection on implanted devices. Ciprofloxacin-loaded zein microspheres were prepared using a phase separation procedure, with particle sizes between 0.5 and 2 {mu}m. Drug encapsulation and drug loading varied with the amount of both zein and ciprofloxacin, and the highest encapsulation efficiency was 8.27% (2 mg/ml ciprofloxacin and 20 mg/ml zein; n = 3). A ciprofloxacin-loaded zein microsphere film (CF-MS film) was generated via solvent evaporation. Continuous drug release from a trypsin-degraded microsphere film was observed for up to 28 days. The liberation of ciprofloxacin from the trypsin-degraded film and the biodegradation of the microsphere film were highly correlated. Proliferation assay of the growth of human umbilical vein endothelial cells (HUVECs) by the MTT method showed that the microsphere film had no toxicity when compared with cells grown on Corning culture plates alone and plates with a zein film alone. Quantification of bacteria adhesion showed that adhesion on the microsphere film is significantly suppressed. In addition, according to the results of bacterial growth tests, ciprofloxacin-loaded microsphere films maintained antibacterial activity for more than 6 days. In contrast, a control medium containing a zein film allowed constant bacterial growth. These results indicate that CF-MS films might be useful as antibacterial films on implanted devices.

  16. Coacervate droplets, proteinoid microspheres, and the genetic apparatus

    Science.gov (United States)

    Fox, S. W.

    1974-01-01

    Differences between typical coacervate droplets and typical proteinoid microspheres are examined. It is pointed out that coacervate droplets are produced from polymers obtained from contemporary organisms. The microspheres considered are aggregates of proteinoid formed from monomeric amino acids under geologically relevant conditions. Aspects regarding the primordial sequence are discussed along with the origin of the genetic apparatus and the genetic code.

  17. Surface wrinkling on polydimethylsiloxane microspheres via wet surface chemical oxidation.

    Science.gov (United States)

    Yin, Jian; Han, Xue; Cao, Yanping; Lu, Conghua

    2014-07-16

    Here we introduce a simple low-cost yet robust method to realize spontaneously wrinkled morphologies on spherical surfaces. It is based on surface chemical oxidation of aqueous-phase-synthesized polydimethylsiloxane (PDMS) microspheres in the mixed H2SO4/HNO3/H2O solution. Consequently, curvature and overstress-sensitive wrinkles including dimples and labyrinth patterns are successfully induced on the resulting oxidized PDMS microspheres. A power-law dependence of the wrinkling wavelength on the microsphere radius exists. The effects of experimental parameters on these tunable spherical wrinkles have been systematically investigated, when the microspheres are pre-deposited on a substrate. These parameters include the radius and modulus of microspheres, the mixed acid solution composition, the oxidation duration, and the water washing post-treatment. Meanwhile, the complicated chemical oxidation process has also been well studied by in-situ optical observation via the microsphere system, which represents an intractable issue in a planar system. Furthermore, we realize surface wrinkled topographies on the whole microspheres at a large scale, when microspheres are directly dispersed in the mixed acid solution for surface oxidation. These results indicate that the introduced wet surface chemical oxidation has the great potential to apply to other complicated curved surfaces for large-scale generation of well-defined wrinkling patterns, which endow the solids with desired physical properties.

  18. DEVELOPMENT AND OPTIMIZATION OF FLOATING MICROSPHERES OF GLICLAZIDE

    Directory of Open Access Journals (Sweden)

    Shardendu Prakash

    2015-05-01

    Full Text Available The objective of the present study was to develop floating microspheres of Gliclazide in order to achieve an extended retention in the upper gastrointestinal tract, which may result in enhanced absorption and thereby improved bioavailability. The present study involves preparation and evaluation of floating microspheres using Gliclazide as a model drug for prolongation of the gastric retention time. As gliclazide is mainly absorbed from stomach, thus using floating microspheres as a mode of drug delivery helps in increasing its residence time and hence increasing the bioavailability of drug. The microspheres were prepared by the Ionic gelation method. The average diameter and surface morphology of the prepared microspheres were characterized by optical microscope and scanning electron microscopic methods respectively. The prepared microspheres were evaluated for particle size, micromeritic study, drug entrapment efficiency, in vitro buoyancy, swelling index and in vitro release. The effect of various formulation variables on the size and drug release was also investigated. All the formulated microspheres were found to possess good flow properties. Scanning electron microscopy confirmed spherical structure of the prepared microspheres. The best formulation F3 drug release kinetics were evaluated using Zero order, First order, Higuchi model, Korsmeyer - Peppas model. After the interpretation of data that was based on the value of a resulting regression coefficient, it was observed that the Korsmeyer- Peppas model has a highest regression coefficient values indicating that the drug release was based on the erosion of polymeric chain matrix.

  19. Controlling silk fibroin microspheres via molecular weight distribution

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Dong-Mei; Pan, Jue-Jing; Wang, Qun; Liu, Xin-Fang; Wang, Hui [National Engineering Laboratory for Modern Silk, College for Textile and Clothing Engineering, Soochow University, Suzhou, Jiangsu 215123 (China); Zhang, Ke-Qin, E-mail: kqzhang@suda.edu.cn [National Engineering Laboratory for Modern Silk, College for Textile and Clothing Engineering, Soochow University, Suzhou, Jiangsu 215123 (China); Research Center of Cooperative Innovation for Functional Organic/Polymer Material Micro/Nanofabrication, Soochow University, Suzhou, Jiangsu 215123 (China)

    2015-05-01

    Silk fibroin (SF) microspheres were produced by salting out SF solution via the addition of potassium phosphate buffer solution (K{sub 2}HPO{sub 4}–KH{sub 2}PO{sub 4}). The morphology, size and polydispersity of SF microspheres were adjusted by changing the molecular weight (MW) distribution and concentration of SF, as well as the ionic strength and pH of the buffer solution. Changing the conditions under which the SF fiber dissolved in the Lithium Boride (LiBr) solution resulted in altering the MW distribution of SF solution. Under optimal salting-out conditions (ionic strength > 0.7 M and pH > 7) and using a smaller and narrower SF MW distribution, SF microspheres with smoother shapes and more uniform sizes were produced. Meanwhile, the size and polydispersity of the microspheres increased when the SF concentration was increased from 0.25 mg/mL to 20 mg/mL. The improved SF microspheres, obtained by altering the distribution of molecular weight, have potential in drug and gene delivery applications. - Highlights: • MW distribution was changed by applying different dissolving methods of SF fiber. • Smaller and narrower MW distribution improves the quality of SF microspheres. • Size and polydispersity of microspheres increase as SF concentration increases. • Improved SF microspheres have potential in drug and gene delivery applications.

  20. Formulation, optimization and evaluation of sustained release microsphere of ketoprofen

    Directory of Open Access Journals (Sweden)

    V Chirag Prajapati

    2012-01-01

    Full Text Available The objective of this study is to formulate ketoprofen loaded microspheres of Acrycoat S100 by an o/w emulsion solvent evaporation method. It potently inhibits the enzyme cyclooxygenase resulting in prostaglandin synthesis inhibition. Ketoprofen causes an irritation in the gastrointestinal mucous membrane and possesses a bitter taste and aftertaste. The half-life in plasma is about 1-2hrs. This makes ketoprofen a very good candidate for the formulation of controlled release dosage forms. Ketoprofen microspheres help to protect the gastric mucous membrane from drug irritation and to mask its taste. The prepared microspheres were evaluated for micromeritic properties, particle size, effect of surfactant concentration, percentage yield, incorporation efficiency, drug polymer compatibility (IR and DSC study, scanning electron microscopy and in vitro drug release. The microspheres produced exhibited good encapsulation efficiencies and micromeritic properties. Encapsulation efficiency of microsphere is around 78%. The mean diameters of microspheres were found in required micrometer range. The results of optimized formulations showed a narrow size distribution and smooth surface. The DSC and the FTIR analysis showed the absence of any potent incompatibility between the drug and the polymer. In-vitro release showed 86.4% drug release after 12 hours. Results of present study suggest that Acrycoat S100 loaded microsphere of ketoprofen can be successfully designed to develop sustained drug delivery system. The solvent evaporation method is a suitable technique for the preparation of Acrycoat S100 microspheres for controlling the release of Ketoprofen for a prolonged duration.

  1. Risperidone for the treatment of acute mania in children and adolescents with bipolar disorder: a randomized, double-blind, placebo-controlled study.

    Science.gov (United States)

    Haas, Magali; Delbello, Melissa P; Pandina, Gahan; Kushner, Stuart; Van Hove, Ilse; Augustyns, Ilse; Quiroz, Jorge; Kusumakar, Vivek

    2009-11-01

    To evaluate the efficacy, safety, and tolerability of risperidone monotherapy for the treatment of an acute mixed or manic episode in children and adolescents with bipolar I disorder. This randomized, placebo-controlled, double-blind, 3-arm study (N = 169) included children and adolescents (ages 10-17 years) with a DSM-IV diagnosis of bipolar I disorder, experiencing a manic or mixed episode. Study participants were randomized to placebo (n = 58), risperidone 0.5-2.5 mg/day (n = 50), or risperidone 3-6 mg/day (n = 61) for 3 weeks. The primary efficacy measure was change in Young Mania Rating Scale (YMRS) total score from baseline to end point. Safety assessments included adverse event (AE) monitoring and scores on extrapyramidal symptom rating scales. Improvement in mean YMRS total score was significantly greater in risperidone-treated subjects than in placebo-treated subjects [mean change (SD) -9.1 (11.0) for placebo; -18.5 (9.7) for risperidone 0.5-2.5 mg (p children and adolescents experiencing acute manic or mixed episodes of bipolar I disorder. Results indicate that risperidone 0.5-2.5 mg has a better benefit-risk profile than risperidone 3-6 mg.

  2. Optimization of sustained release aceclofenac microspheres using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Deshmukh, Rameshwar K.; Naik, Jitendra B., E-mail: jitunaik@gmail.com

    2015-03-01

    Polymeric microspheres containing aceclofenac were prepared by single emulsion (oil-in-water) solvent evaporation method using response surface methodology (RSM). Microspheres were prepared by changing formulation variables such as the amount of Eudragit® RS100 and the amount of polyvinyl alcohol (PVA) by statistical experimental design in order to enhance the encapsulation efficiency (E.E.) of the microspheres. The resultant microspheres were evaluated for their size, morphology, E.E., and in vitro drug release. The amount of Eudragit® RS100 and the amount of PVA were found to be significant factors respectively for determining the E.E. of the microspheres. A linear mathematical model equation fitted to the data was used to predict the E.E. in the optimal region. Optimized formulation of microspheres was prepared using optimal process variables setting in order to evaluate the optimization capability of the models generated according to IV-optimal design. The microspheres showed high E.E. (74.14 ± 0.015% to 85.34 ± 0.011%) and suitably sustained drug release (minimum; 40% to 60%; maximum) over a period of 12 h. The optimized microspheres formulation showed E.E. of 84.87 ± 0.005 with small error value (1.39). The low magnitudes of error and the significant value of R{sup 2} in the present investigation prove the high prognostic ability of the design. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) revealed the dispersion of drug within microspheres formulation. The microspheres were found to be discrete, spherical with smooth surface. The results demonstrate that these microspheres could be promising delivery system to sustain the drug release and improve the E.E. thus prolong drug action and achieve the highest healing effect with minimal gastrointestinal side effects. - Highlights: • Aceclofenac microspheres

  3. Computational dynamics of acoustically-driven microsphere systems

    CERN Document Server

    Glosser, Connor A; Dault, Daniel L; Piermarocchi, Carlo; Shanker, Balasubramaniam

    2015-01-01

    We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the microsphere system with a time-dependent integral equation solver for the acoustic field that makes use of fields represented as surface expansions in spherical harmonic basis functions. The presented approach allows us to describe the inter-particle interaction induced by the field as well as the dynamics of trapping in counter-propagating acoustic pulses. The integral equation formulation leads to equations of motion for the microspheres describing the effect of non-dissipative drag forces. We show (1) that the field-induced interactions between the microspheres give rise to effective dipolar interactions, with effective dipoles defined by their velocities, and (2) that the dominant effect of an ultrasound pulse through a cloud of microspheres gives rise mainly to a translation ...

  4. Hollow porous-wall glass microspheres for hydrogen storage

    Science.gov (United States)

    Heung, Leung K.; Schumacher, Ray F.; Wicks, George G.

    2010-02-23

    A porous wall hollow glass microsphere is provided having a diameter range of between 1 to 200 microns, a density of between 1.0 to 2.0 gm/cc, a porous-wall structure having wall openings defining an average pore size of between 10 to 1000 angstroms, and which contains therein a hydrogen storage material. The porous-wall structure facilitates the introduction of a hydrogen storage material into the interior of the porous wall hollow glass microsphere. In this manner, the resulting hollow glass microsphere can provide a membrane for the selective transport of hydrogen through the porous walls of the microsphere, the small pore size preventing gaseous or liquid contaminants from entering the interior of the hollow glass microsphere.

  5. Resolution enhancement phase-contrast imaging by microsphere digital holography

    Science.gov (United States)

    Wang, Yunxin; Guo, Sha; Wang, Dayong; Lin, Qiaowen; Rong, Lu; Zhao, Jie

    2016-05-01

    Microsphere has shown the superiority of super-resolution imaging in the traditional 2D intensity microscope. Here a microsphere digital holography approach is presented to realize the resolution enhancement phase-contrast imaging. The system is designed by combining the microsphere with the image-plane digital holography. A microsphere very close to the object can increase the resolution by transforming the object wave from the higher frequency to the lower one. The resolution enhancement amplitude and phase images can be retrieved from a single hologram. The experiments are carried on the 1D and 2D gratings, and the results demonstrate that the observed resolution has been improved, meanwhile, the phase-contrast image is obtained. The proposed method can improve the transverse resolution in all directions based on a single exposure. Furthermore, this system has extended the application of the microsphere from the conventional 2D microscopic imaging to 3D phase-contrast microscopic imaging.

  6. Study on the Degradation of Polylactide Microsphere In Vitro

    Institute of Scientific and Technical Information of China (English)

    HeYing; WeiShuli

    2001-01-01

    This report concentrated on the rules and mechanism of the degradation of polylactide and the microspheres. The rate of degradation was assessed with five methods: observation of microsphere surface morphology by SEM, determination of the weight loss of the microspheres, determination of the molecular mass of the polymers by GPC, determination of pH and determination of the contents of lactic acid by UV spectrophotometry. The degradation of polylactide microspheres showed two-phase characteristics. At the early stage of the degradation, the high molecular mass polymers were cleaved into lower molecular mass fractions and at the late stage, there was a period of erosion and weight loss of the microspheres. The degradation was much slower for polymers with a higher molecular mass. The polylactide degradation showed good regularity.

  7. Labelling of silica microspheres with fluorescent lanthanide-doped LaF{sub 3} nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yong [Division of Bioengineering, Faculty of Engineering, National University of Singapore, 117576, Singapore (Singapore); Lu Meihua [Division of Bioengineering, Faculty of Engineering, National University of Singapore, 117576, Singapore (Singapore)

    2007-07-11

    Fluorescent microspheres have been demonstrated to be useful in a variety of biological applications. Fluorescent silica or polymer microspheres have been produced by incorporation of chromophores into the microspheres, which usually produces microspheres with nonuniform sizes and reduced fluorescence. Here we present a simple and straightforward method to produce silica microspheres with fluorescent lanthanide-doped LaF{sub 3} nanocrystals grown on the surface. LaF{sub 3} nanocrystals are in situ grown on silica microspheres of different sizes to form a raspberry-like structure. The microspheres exhibit strong fluorescence and the colour could be altered by changing the lanthanide ions doped in LaF{sub 3} nanocrystals.

  8. A retrospective study of risperidone oral solution versus risperidone tablets in treating schizophrenia%利培酮口服液与片剂治疗精神分裂症的回顾性分析

    Institute of Scientific and Technical Information of China (English)

    钟智勇; 吴小立; 韩自力; 张晋碚

    2011-01-01

    AIM To retrospectively evaluate the efficacy and safety of risperidone oral solution and risperidone tablets in treating schizophrenia. METHODS A total of 204 patients, who met diagnostic criteria of CCMD-3 for schizophrenia and were hospitalized in our department of psychiatry from May 2007 to May 2011, included 85 patients in risperidone oral solution group and 119 patients in risperidone tablets group. Before the treatment and at the end of the 4 th week of the treatment, all patients were assessed by Brief Psychiatric Rating Scale (BPRS), Scale for the Assessment of Negative Symptoms (SANS), Scale for the Assessment of Positive Symptoms (SAPS), Treatment Emergent Symptom Scale (TESS) and laboratory tests. RESULTS There were significant differences in total scales of TESS and the rates of ECG abnormalities and extrapyramidal side effects between the risperidone oral solution group and risperidone tablets group (6.62 ± 3.65 vs. 7.97 ± 4.93, 16.5%vs. 28.6%, 23.5% vs. 40.3%, P0.05) in the total scales of BPRS, SANS, SAPS and other index of safety. CONCLUSION The efficacy of risperidone oral solution and risperidone tablets in treating schizophrenia was equal, but risperidone oral solution is superior to risperidone tablets on the safety.%目的 比较利培酮口服液与利培酮片剂治疗精神分裂症的疗效与安全性.方法 回顾性分析2007年5月至201 1年5月在本科室住院4 wk以上,符合CCMD-3精神分裂症诊断标准的患者共204例,其中利培酮口服液组85例,利培酮片剂组119例.比较2组患者治疗前与治疗4 wk末简明精神病评定量表、阳性症状量表、阴性症状量表、副反应量表总分以及实验室检查的差异.结果 2组治疗4 wk末简明精神病评定量表、阳性症状量表、阴性症状量表分值无显著差异(P>0.05).利培酮口服液组副反应量表总分、心电图异常发生率以及锥体外系反应发生率明显低于利培酮片剂组(6.62±3.65 vs.7.97±4.93,16.5

  9. Microwire formation based on dielectrophoresis of electroless gold plated polystyrene microspheres

    Institute of Scientific and Technical Information of China (English)

    Jiang Hong-Yuan; Ren Yu-Kun; Tao Ye

    2011-01-01

    Microspheres coated with a perfectly conductive surface have many advantages in the applications of biosensors and micro-electromechanical systems. Polystyrene microspheres with the diameter of 10 μm were coated with a 50 nmthick gold layer using an electroless gold plating approach. Dielectrophoresis (DEP) for bare microspheres and shelled microspheres was theoretically analysed and the real part of the Clausius-Mossotti factor was calculated for the two kinds of microspheres. The experiments on the dielectrophoretic characterisation of the uncoated polystyrene microspheres and gold coated polystyrene microspheres (GCPMs) were carried out. Experimental results showed that the gold coated polystyrene microspheres were only acted by a positive dielectrophoretic force when the frequency was below 40M Hz,while the uncoated polystyrene microspheres were governed by a negative dielectrophoretic force in this frequency range.The gold coated polystyrene microspheres were exploited to form the microwire automatically according to their stable dielectrophoretic and electric characterisations.

  10. Tolerability, Safety, and Benefits of Risperidone in Children and Adolescents with Autism: 21-Month Follow-up After 8-Week Placebo-Controlled Trial.

    Science.gov (United States)

    Aman, Michael; Rettiganti, Mallikarjuna; Nagaraja, Haikady N; Hollway, Jill A; McCracken, James; McDougle, Christopher J; Tierney, Elaine; Scahill, Lawrence; Arnold, L Eugene; Hellings, Jessica; Posey, David J; Swiezy, Naomi B; Ghuman, Jaswinder; Grados, Marco; Shah, Bhavik; Vitiello, Benedetto

    2015-08-01

    Risperidone has demonstrated efficacy for acute (8 week) and intermediate length (6 month) management of severe irritability and aggression in children and adolescents with autism. Less is known about the long-term effects of risperidone exposure in this population. We examined the tolerability, safety, and therapeutic benefit of risperidone exposure over a 1-2 year follow-up period. In a naturalistic study, 84 children and adolescents 5-17 years of age (from an original sample of 101) were assessed an average of 21.4 months after initial entry into a placebo-controlled 8 week trial of risperidone for children and adolescents with autism and severe irritability. They were assessed at baseline and at follow-up on safety and tolerability measures (blood, urinalysis, electrocardiogram [ECG], medical history, vital signs, neurological symptoms, other adverse events), developmental measures (adaptive behavior, intelligence quotient [IQ]), and standardized rating instruments. Treatment over the follow-up period, after completion of protocol participation, was uncontrolled. Statistical analyses assessed outcome over time with or without prolonged risperidone therapy. Two-thirds of the 84 subjects continued to receive risperidone (mean 2.47 mg/day, S.D. 1.29 mg). At follow-up, risperidone was associated with more enuresis, more excessive appetite, and more weight gain, but not more adverse neurological effects. No clinically significant events were noted on blood counts, chemistries, urinalysis, ECG, or interim medical history. Regardless of drug condition at follow-up, there was considerable improvement in maladaptive behavior compared with baseline, including core symptoms associated with autism. Height and weight gains were elevated with risperidone. Social skills on Vineland Adaptive Behavior Scale (VABS) improved with risperidone. Parent-rated Aberrant Behavior Checklist (ABC) Irritability subscale scores were reduced in those taking risperidone at follow

  11. An open-label trial of risperidone and fluoxetine in children with autistic disorder

    Directory of Open Access Journals (Sweden)

    Desousa Avinash

    2010-01-01

    Full Text Available Objective: Various studies have shown the effectiveness of risperidone and fluoxetine in the management of behavioral problems in autism. Aim: The purpose of this study was to compare these two drugs in the management of behavioral problems in autism. Materials and Methods: Forty children with autism were divided into 2 groups in a 16-week open trial that compared these two drugs. Parents rated the children using the Aberrant Behavior Checklist (ABC and the Conners′ Parent Rating Scale - Revised (CPRS-R. The author rated the children using the Children′s Psychiatric Rating Scale and Clinical Global Impression (CGI Scale. Results: The risperidone group showed significant improvement in areas like irritability and hyperactivity, while the fluoxetine group showed significant improvement in speech deviance, social withdrawal and stereotypy. When the two drugs were compared, fluoxetine showed greater improvement in stereotypy, while both drugs showed improvement on the general autism scale; and on anger, hyperactivity and irritability scales. Conclusions : In this open trial, both drugs were well tolerated and appeared to be beneficial in the treatment of common behavioral problems in children with autism. Further controlled and double-blind studies in larger samples are warranted.

  12. Delayed drug interactions in psychiatry: armodafinil and risperidone as a potential case in point.

    Science.gov (United States)

    Andrade, Chittaranjan

    2015-12-01

    Modafinil or armodafinil (ar/mod) augmentation of antipsychotic medication in schizophrenia patients may be considered with a view to reduce negative symptoms associated with the illness or excessive daytime drowsiness due to any cause. The available data suggest that there is no role for ar/mod in reducing negative symptom burden. A recent pharmacokinetic (PK) study suggested that armodafinil (250 mg/d) reduces key PK parameters of risperidone by about 50%, and key PK parameters of 9-hydroxyrisperidone (paliperidone) by about 20%-30%, probably through induction of CYP3A4. Ar/mod augmentation is therefore best avoided in patients receiving risperidone or paliperidone (and most other atypical antipsychotic drugs, as well, because most atypical antipsychotics are metabolized by enzymes that ar/mod induce). If the ar/mod-antipsychotic drug combination is necessary, for whatever reason, then the dose of the atypical antipsychotic drug may need to be appropriately raised. If this is not done, relapse may occur; because the relapse may postdate the introduction of ar/mod by many months, the causal role of a metabolic drug interaction may not be suspected, and physicians may attribute the relapse to the natural course of the illness. Physicians need to be aware that any agent that induces the metabolism of psychotropic drugs that are used in maintenance therapy may, through lowered psychotropic drug levels, result in a delayed drug interaction that is characterized by illness relapse.

  13. Risperidone long-acting injection: a review of its long term safety and efficacy

    Directory of Open Access Journals (Sweden)

    Michael K Rainer

    2008-08-01

    Full Text Available Michael K RainerMemory-Clinic and Psychiatric Department, Donauspital, Vienna, AustriaAbstract: A long-acting form of the second-generation antipsychotic drug risperidone is now broadly available for the treatment of schizophrenia and closely related psychiatric conditions. It combines the advantage of previously available depot formulations for first-generation drugs with the favorable characteristics of the modern “atypical” antipsychotics, namely higher efficacy in the treatment of the negative symptoms of schizophrenia and reduced motor disturbances. Published clinical studies show an objective clinical efficacy (as per psychiatric symptom scores and relapse data that exceeds that of oral atypical antipsychotics when patients are switched to the long-acting injectable form, a low incidence of treatment-emergent extrapyramidal side effects, and very good acceptance by patients. Available data for maintenance treatment of bipolar disorder show equivalence with the oral form instead of superiority, but are still limited. As it seems likely that efficacy benefits are mostly due to the fact that the injectable form reduces the demand for patient compliance to one physician visit every 2 weeks instead of self-administration on a daily or twice-daily basis, additional potential could exist in other psychiatric disorders where atypical antipsychotic drugs are of benefit but where patient adherence to treatment schedules is typically low.Keywords: risperidone, schizophrenia, psychotic disorders, patient compliance; delayed-action preparations, injections, intramuscular

  14. Selective acquired long QT syndrome (saLQTS upon risperidone treatment

    Directory of Open Access Journals (Sweden)

    Lazarczyk Maciej

    2012-12-01

    Full Text Available Abstract Background Numerous structurally unrelated drugs, including antipsychotics, can prolong QT interval and trigger the acquired long QT syndrome (aLQTS. All of them are thought to act at the level of KCNH2, a subunit of the potassium channel. Although the QT-prolonging drugs are proscribed in the subjects with aLQTS, the individual response to diverse QT-prolonging drugs may vary substantially. Case presentation We report here a case of aLQTS in response to small doses of risperidone that was confirmed at three independent drug challenges in the absence of other QT-prolonging drugs. On the other hand, the patient did not respond with QT prolongation to some other antipsychotics. In particular, the administration of clozapine, known to be associated with higher QT-prolongation risk than risperidone, had no effect on QT-length. A detailed genetic analysis revealed no mutations or polymorphisms in KCNH2, KCNE1, KCNE2, SCN5A and KCNQ1 genes. Conclusions Our observation suggests that some patients may display a selective aLQTS to a single antipsychotic, without a potassium channel-related genetic substrate. Contrasting with the idea of a common target of the aLQTS-triggerring drugs, our data suggests existence of an alternative target protein, which unlike the KCNH2 would be drug-selective.

  15. Comparative study of clozapine versus risperidone in treatment-naive, first-episode schizophrenia: A pilot study

    Directory of Open Access Journals (Sweden)

    Sukhtej Sahni

    2016-01-01

    Interpretation & conclusions: The findings of this preliminary study showed clozapine as a better choice than risperidone in terms of efficacy, tolerability and better quality of life in treatment-naive, first-episode schizophrenia. However, further studies need to be done on a larger group of patients to confirm the findings.

  16. A Double-Blind Placebo Controlled Trial of "Ginkgo Biloba" Added to Risperidone in Patients with Autistic Disorders

    Science.gov (United States)

    Hasanzadeh, Elmira; Mohammadi, Mohammad-Reza; Ghanizadeh, Ahmad; Rezazadeh, Shams-Ali; Tabrizi, Mina; Rezaei, Farzin; Akhondzadeh, Shahin

    2012-01-01

    "Ginkgo biloba" has been reported to affect the neurotransmitter system and to have antioxidant properties that could impact the pathogenesis of Autism Spectrum Disorder. Based on these studies, we decided to assess the effectiveness of "Ginkgo biloba" extract (Ginko T.D., Tolidaru, Iran) as an adjunctive agent to risperidone in the treatment of…

  17. Effects of risperidone on core symptoms of autistic disorder based on childhood autism rating scale: An open label study

    Directory of Open Access Journals (Sweden)

    Padideh Ghaeli

    2014-01-01

    Full Text Available Background: The aim of the present study was to evaluate the effect of risperidone in patients afflicted by autistic disorder especially with regards to its three core symptoms, including "relating to others", "communication skills", and "stereotyped behaviors" based on Childhood Autism Rating Scale (CARS. Materials and Methods: An 8-week open-label study of risperidone for treatment of autistic disorder in children 4-17 years old was designed. Risperidone dose titration was as follow: 0.02 mg/kg/day at the first week, 0.04 mg/kg/day at the second week, and 0.06 mg/kg/day at the third week and thereafter. The outcome measures were scores obtained by CARS, Aberrant Behavior Checklist (ABC, and Clinical Global Impression-Improvement (CGI-I scale. Results: Fifteen patients completed this study. After 8 weeks, CARS total score decreased significantly, (P=0.001. At the end of the study, social interactions and verbal communication skills of the patients were significantly improved (P<0.001, P=0.03, respectively. However, stereotypic behaviors did not show any significant change in this study. Increase in appetite and somnolence were the most reported side effects. Conclusion: This study suggests that risperidone may be an effective treatment for the management of core symptoms of autistic disorder.

  18. Add-on effects of a low-dose aripiprazole in resolving hyperprolactinemia induced by risperidone or paliperidone.

    Science.gov (United States)

    Qiao, Ying; Yang, Fuzhong; Li, Chunbo; Guo, Qian; Wen, Hui; Zhu, Suoyu; Ouyang, Qiong; Shen, Weidi; Sheng, Jianhua

    2016-03-30

    This study investigated the effects of a low-dose aripiprazole adjunctive treatment for risperidone- or paliperidone-induced hyperprolactinemia in Han Chinese women with schizophrenia. After 4 weeks of risperidone or paliperidone treatment, 60 out of 66 patients improved significantly and experienced hyperprolactinemia. They were randomly assigned to the treatment group (aripiprazole adjunctive treatment) (n=30) or control group (non-adjunctive treatment) (n=30). The dosage of risperidone and paliperidone were maintained; and aripiprazole was maintained at 5mg/day during the 8-week study period. The prolactin levels at the end of the 8th week were significantly lower in the treatment group than in the control group. The estradiol level correlated negatively with serum prolactin level both in the treatment group and the control group at the end of the 8th week and the 4th week respectively. The Positive and Negative Syndrome Scale score improved significantly during the 8-week study period in both groups. The incidence of treatment-emergent adverse event was similar in two groups. Low-dose aripiprazole adjunctive treatment is effective in relieving risperidone- and paliperidone-induced hyperprolactinemia in female schizophrenic patients without increasing adverse event.

  19. Mesoporous metal oxide microsphere electrode compositions and their methods of making

    Energy Technology Data Exchange (ETDEWEB)

    Parans Paranthaman, Mariappan; Bi, Zhonghe; Bridges, Craig A.; Brown, Gilbert M.

    2017-04-11

    Compositions and methods of making are provided for treated mesoporous metal oxide microspheres electrodes. The compositions include microspheres with an average diameter between about 200 nanometers and about 10 micrometers and mesopores on the surface and interior of the microspheres. The methods of making include forming a mesoporous metal oxide microsphere composition and treating the mesoporous metal oxide microspheres by at least annealing in a reducing atmosphere, doping with an aliovalent element, and coating with a coating composition.

  20. A pharmacogenetic study of risperidone on histamine H3 receptor gene (HRH3) in Chinese Han schizophrenia patients.

    Science.gov (United States)

    Wei, Zhiyun; Wang, Lei; Zhang, Mengmeng; Xuan, Jiekun; Wang, Yang; Liu, Baocheng; Shao, Liyan; Li, Jun; Zeng, Zhen; Li, Tao; Liu, Jie; Wang, Ti; Zhang, Ming; Qin, Shengying; Xu, Yifeng; Feng, Guoyin; He, Lin; Xing, Qinghe

    2012-06-01

    Evidence suggests that the human histamine H3 receptor (HRH3) may be involved in the pharmacodynamics of risperidone and influence clinical efficacy. More information on the pharmacogenetics of this receptor may therefore be useful in developing individualized therapy. However, to our knowledge, no study has been reported in this area. The aim of this investigation was to clarify whether H3 receptor polymorphism could affect risperidone efficacy. We genotyped tag single nucleotide polymorphisms (SNPs) of the HRH3 gene (rs3787429 and rs3787430) and analyzed their association with the reduction of Brief Psychiatric Rating Scale (BPRS) score in Chinese Han schizophrenia patients (N = 129), following an eight-week period of risperidone monotherapy. The confounding effects of non-genetic factors were estimated, and then the significant one was included as the covariate for adjustment in statistical analysis. Baseline symptom score was the only significant confounding effect and thus the covariate. After adjustment, significant association of HRH3 with antipsychotic efficacy was detected (for rs3787429, p = 0.013, 0.087 after 4 weeks and 8 weeks of treatment, respectively; for rs3787430, p = 0.024, 0.010 after 4 weeks and 8 weeks of treatment, respectively) and stood up to conservative Bonferroni correction. Our results demonstrate that polymorphism of the HRH3 gene may be a potential genetic marker for predicting the therapeutic effect of risperidone, and suggest novel pharmacological links between HRH3 and risperidone. Further studies with larger samples and different ethnic populations are warranted to confirm our results.

  1. Movement disorders in elderly users of risperidone and first generation antipsychotic agents: a Canadian population-based study.

    Directory of Open Access Journals (Sweden)

    Irina Vasilyeva

    Full Text Available BACKGROUND: Despite concerns over the potential for severe adverse events, antipsychotic medications remain the mainstay of treatment of behaviour disorders and psychosis in elderly patients. Second-generation antipsychotic agents (SGAs; e.g., risperidone, olanzapine, quetiapine have generally shown a better safety profile compared to the first-generation agents (FGAs; e.g., haloperidol and phenothiazines, particularly in terms of a lower potential for involuntary movement disorders. Risperidone, the only SGA with an official indication for the management of inappropriate behaviour in dementia, has emerged as the antipsychotic most commonly prescribed to older patients. Most clinical trials evaluating the risk of movement disorders in elderly patients receiving antipsychotic therapy have been of limited sample size and/or of relatively short duration. A few observational studies have produced inconsistent results. METHODS: A population-based retrospective cohort study of all residents of the Canadian province of Manitoba aged 65 and over, who were dispensed antipsychotic medications for the first time during the time period from April 1, 2000 to March 31, 2007, was conducted using Manitoba's Department of Health's administrative databases. Cox proportional hazards models were used to determine the risk of extrapyramidal symptoms (EPS in new users of risperidone compared to new users of FGAs. RESULTS: After controlling for potential confounders (demographics, comorbidity and medication use, risperidone use was associated with a lower risk of EPS compared to FGAs at 30, 60, 90 and 180 days (adjusted hazard ratios [HR] 0.38, 95% CI: 0.22-0.67; 0.45, 95% CI: 0.28-0.73; 0.50, 95% CI: 0.33-0.77; 0.65, 95% CI: 0.45-0.94, respectively. At 360 days, the strength of the association weakened with an adjusted HR of 0.75, 95% CI: 0.54-1.05. CONCLUSIONS: In a large population of elderly patients the use of risperidone was associated with a lower risk of EPS

  2. PREPARATION AND CHARACTERIZATION OF TRAMADOL HYDROCHLORIDE MICROSPHERES

    Directory of Open Access Journals (Sweden)

    Patel Keyur

    2015-10-01

    Full Text Available Tramadol HCl was microencapsulated with Ethylcellulose using multiple emulsion solvent evaporation method. A 32 factorial design employed to study the effect of drug: polymer ratio and volume of External phase (1% PVA on % yield, % encapsulation efficiency, particle size, % drug release rate. The drug: polymer ratio and volume of continuous phase were significant effect on % yield, % entrapment efficiency, particle size, % drug release rate. % drug release was Biphasic system first initially bursting effect and finally sustained. Higher Percentage yield (77.4% and Higher Percentage Encapsulation Efficiency(31.1% were observed in Batch EC3. All the microspheres were spherical in nature its surface was smooth observed in SEM report.

  3. Measurements of extrinsic fluorescence in Intralipid and polystyrene microspheres

    Science.gov (United States)

    Du Le, Vinh Nguyen; Nie, Zhaojun; Hayward, Joseph E.; Farrell, Thomas J.; Fang, Qiyin

    2014-01-01

    The fluorescence of Intralipid and polystyrene microspheres with sphere diameter of 1 µm at a representative lipid and microsphere concentration for simulation of mucosal tissue scattering has not been a subject of extensive experimental study. In order to elucidate the quantitative relationship between lipid and microsphere concentration and the respective fluorescent intensity, the extrinsic fluorescence spectra between 360 nm and 650 nm (step size of 5 nm) were measured at different lipid concentrations (from 0.25% to 5%) and different microsphere concentrations (0.00364, 0.0073, 0.0131 spheres per cubic micrometer) using laser excitation at 355 nm with pulse energy of 2.8 µJ. Current findings indicated that Intralipid has a broadband emission between 360 and 650 nm with a primary peak at 500 nm and a secondary peak at 450 nm while polystyrene microspheres have a single peak at 500 nm. In addition, for similar scattering properties the fluorescence of Intralipid solutions is approximately three-fold stronger than that of the microsphere solutions. Furthermore, Intralipid phantoms with lipid concentrations ~2% (simulating the bottom layer of mucosa) produce up to seven times stronger fluorescent emission than phantoms with lipid concentration ~0.25% (simulating the top layer of mucosa). The fluoresence decays of Intralipid and microsphere solutions were also recorded for estimation of fluorescence lifetime. PMID:25136497

  4. Insulin delivery through nasal route using thiolated microspheres.

    Science.gov (United States)

    Nema, Tarang; Jain, Ashish; Jain, Aviral; Shilpi, Satish; Gulbake, Arvind; Hurkat, Pooja; Jain, Sanjay K

    2013-01-01

    The aim of the present study was to investigate the potential of developed thiolated microspheres for insulin delivery through nasal route. In the present study, cysteine was immobilized on carbopol using EDAC. A total of 269.93 µmol free thiol groups per gram polymer were determined. The prepared nonthiolated and thiolated microspheres were studied for particle shape, size, drug content, swellability, mucoadhesion and in vitro insulin release. The thiolated microspheres exhibited higher mucoadhesion due to formation of covalent bonds via disulfide bridges with the mucus gel layer. Drug permeation through goat nasal mucosa of nonthiolated and thiolated microspheres were found as 52.62 ± 2.4% and 78.85 ± 3.1% in 6 h, respectively. Thiolated microspheres bearing insulin showed better reduction in blood glucose level (BGL) in comparison to nonthiolated microspheres as 31.23 ± 2.12% and 75.25 ± 0.93% blood glucose of initial BGL were observed at 6 h after nasal delivery of thiolated and nonthiolated microspheres in streptozotocin-induced diabetic rabbits.

  5. Bioavailability enhancement of verapamil HCl via intranasal chitosan microspheres.

    Science.gov (United States)

    Abdel Mouez, Mamdouh; Zaki, Noha M; Mansour, Samar; Geneidi, Ahmed S

    2014-01-23

    Chitosan microspheres are potential drug carriers for maximizing nasal residence time, circumventing rapid mucociliary clearance and enhancing nasal absorption. The aim of the present study was to develop and characterize chitosan mucoadhesive microspheres of verapamil hydrochloride (VRP) for intranasal delivery as an alternative to oral VRP which suffers low bioavailability (20%) due to extensive first pass effect. The microspheres were produced using a spray-drying and precipitation techniques and characterized for morphology (scanning electron microscopy), particle size (laser diffraction method), drug entrapment efficiency, thermal behavior (differential scanning calorimetry) and crystallinity (X-ray diffractometric studies) as well as in vitro drug release. Bioavailability of nasal VRP microspheres was studied in rabbits and the results were compared to those obtained after nasal, oral and intravenous administration of VRP solution. Results demonstrated that the microspheres were spherical with size 21-53 μm suitable for nasal deposition. The spray-drying technique was superior over precipitation technique in providing higher VRP entrapment efficiency and smaller burst release followed by a more sustained one over 6h. The bioavailability study demonstrated that the nasal microspheres exhibited a significantly higher bioavailability (58.6%) than nasal solution of VRP (47.8%) and oral VRP solution (13%). In conclusion, the chitosan-based nasal VRP microspheres are promising for enhancing VRP bioavailability by increasing the nasal residence time and avoiding the first-pass metabolism of the drug substance. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Removal of chloroform from biodegradable therapeutic microspheres by radiolysis.

    Science.gov (United States)

    Zielhuis, S W; Nijsen, J F W; Dorland, L; Krijger, G C; van Het Schip, A D; Hennink, W E

    2006-06-06

    Radioactive holmium-166 loaded poly(l-lactic acid) microspheres are promising systems for the treatment of liver malignancies. These microspheres are loaded with holmium acetylacetonate (HoAcAc) and prepared by a solvent evaporation method using chloroform. After preparation the microspheres (Ho-PLLA-MS) are activated by neutron irradiation in a nuclear reactor. It was observed that relatively large amounts of residual chloroform (1000-6000 ppm) remained in the microspheres before neutron irradiation. Since it is known that chloroform is susceptible for high-energy radiation, we investigated whether neutron and gamma irradiation could result in the removal of residual chloroform in HoAcAc-loaded and placebo PLLA-MS by radiolysis. To investigate this, microspheres with relatively high and low amounts of residual chloroform were subjected to irradiation. The effect of irradiation on the residual chloroform levels as well as other microsphere characteristics (morphology, size, crystallinity, molecular weight of PLLA and degradation products) were evaluated. No chloroform in the microspheres could be detected after neutron irradiation. This was also seen for gamma irradiation at a dose of 200 kGy phosgene, which can be formed as the result of radiolysis of chloroform, was not detected with gas chromatography-mass spectrometry (GC-MS). A precipitation titration showed that radiolysis of chloroform resulted in the formation of chloride. Gel permeation chromatography and differential scanning calorimetry showed a decrease in molecular weight of PLLA and crystallinity, respectively. However, no differences were observed between irradiated microsphere samples with high and low initial amounts of chloroform. In conclusion, this study demonstrates that neutron and gamma irradiation results in the removal of residual chloroform in PLLA-microspheres.

  7. Autonomic shutdown of lithium-ion batteries using thermoresponsive microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Baginska, Marta; White, Scott R. [306 Talbot Laboratory, Department of Aerospace Engineering, University of Illinois Urbana-Champaign, Urbana, IL (United States); Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL (United States); Blaiszik, Benjamin J.; Sottos, Nancy R. [Department of Materials Science and Engineering, Materials Science and Engineering Building, University of Illinois Urbana-Champaign, Urbana, IL (United States); Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL (United States); Merriman, Ryan J. [306 Talbot Laboratory, Department of Aerospace Engineering, University of Illinois Urbana-Champaign, Urbana, IL (United States); Moore, Jeffrey S. [Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL (United States); Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL (United States)

    2012-05-15

    Autonomic, thermally-induced shutdown of Lithium-ion (Li-ion) batteries is demonstrated by incorporating thermoresponsive polymer microspheres (ca. 4 {mu}m) onto battery anodes or separators. When the internal battery environment reaches a critical temperature, the microspheres melt and coat the anode/separator with a nonconductive barrier, halting Li-ion transport and shutting down the cell permanently. Three functionalization schemes are shown to perform cell shutdown: 1) poly(ethylene) (PE) microspheres coated on the anode, 2) paraffin wax microspheres coated on the anode, and 3) PE microspheres coated on the separator. Charge and discharge capacity is measured for Li-ion coin cells containing microsphere-coated anodes or separators as a function of capsule coverage. For PE coated on the anode, the initial capacity of the battery is unaffected by the presence of the PE microspheres up to a coverage of 12 mg cm{sup -2} (when cycled at 1C), and full shutdown (>98% loss of initial capacity) is achieved in cells containing greater than 3.5 mg cm{sup -2}. For paraffin microspheres coated on the anode and PE microspheres coated on the separator, shutdown is achieved in cells containing coverages greater than 2.9 and 13.7 mg cm{sup -2}, respectively. Scanning electron microscopy images of electrode surfaces from cells that have undergone autonomic shutdown provides evidence of melting, wetting, and resolidification of PE into the anode and polymer film formation at the anode/separator interface. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Preparation of paclitaxel-loaded microspheres with magnetic nanoparticles

    Institute of Scientific and Technical Information of China (English)

    CUI Sheng; SHEN Xiaodong; SHI Ruihua; LIN Benlan; CHEN Ping

    2007-01-01

    The objective of this paper was to prepare paclitaxel-loaded microspheres,a kind of target-orientation anticancer drug.The paclitaxel-loaded microspheres were prepared with magnetic Fe3O4 nanoparticles and taxo1.The morphology was characterized by scanning electron microscopy(SEM),and the average size and the size distribution were determined by a laser-size distributing instrument.High performance liquid chromatography(HPLC)was used to measure the paclitaxel content.Experimental results indicated that the effective drug loading and the entrapment ratio of paclitaxel-loaded microspheres were 1.83% and 92,62%,respectively.

  9. Locomotion of microspheres for imaging and light focusing applications

    CERN Document Server

    Krivitsky, Leonid A; Wang, Zengbo; Lukiyanchuk, Boris

    2013-01-01

    Super-resolution imaging using sub-diffraction field localization by micron sized transparent beads (microspheres) was recently demonstrated [1]. Practical applications in microscopy require control over the positioning of the microspheres. We present a simple method of positioning and controllable movement of a microsphere by using a glass micropipette. This allows sub-diffraction imaging at arbitrary points in three dimensions, as well as the ability to track moving objects. The results are relevant to a broad scope of applications, including sample inspection, and bio-imaging.

  10. Confocal epifluorescence detection for microspheres delivered on disposable microfluidic chip

    Institute of Scientific and Technical Information of China (English)

    Honghua Hu; Xiyun Hou; Guoguang Yang

    2006-01-01

    @@ The laser induced fluorescence (LIF) detection system for 5-μm microspheres delivered on microfluidic chip is presented employing confocal optical scheme. The parameters of the optical system are specifically optimized for single microsphere detection. With the excitation laser spot size of 4.6 μm and optical sectioning power of 27 μm, the lowest concentration detection limit is 0.45 nmol/L, corresponding to only 122 molecules in probe volume. The microsphere detection is carried on successfully with the maximum signal-to-noise ratio (SNR) of 55.7, which provides good detection sensitivity.

  11. Optical properties of metallo-dielectric microspheres in opal structures

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Y; Whitehouse, C; Li, Jensen; Tam, Wing Yim; Chan, C T; Sheng Ping [Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)

    2003-09-03

    We report the fabrication of opal structure using metallo-dielectric silica microspheres. Mono-dispersed silica microspheres were coated with silver using an electrode-less wet-plating technique. Thin slabs of opal were obtained by assembling the silver-coated microspheres between two glass plates using a forced-packing method. The optical properties of the resulting opal structure were studied in the infrared range. Good agreement is obtained with the predictions of a multiple scattering approach, provided that the silver layer is modelled as a silver composite.

  12. Packaged chalcogenide microsphere resonator with high Q-factor

    Science.gov (United States)

    Wang, Pengfei; Ding, Ming; Lee, Timothy; Senthil Murugan, Ganapathy; Bo, Lin; Semenova, Yuliya; Wu, Qiang; Hewak, Dan; Brambilla, Gilberto; Farrell, Gerald

    2013-04-01

    The fabrication and characterization of a packaged As2S3 microsphere resonator coupled to a tapered fiber using a low refractive index UV-curable polymer are reported. Embedding provides an efficient means to remove the highest order whispering gallery modes in the microsphere resonator, thus cleaning the resonator spectrum. At wavelengths near 1549.5 nm, high-Q modes up to 1.8 × 105 can be efficiently excited in a 110 μm diameter chalcogenide microsphere via evanescent coupling from a 2 μm diameter tapered silica fiber. The device photosensitivity, useful for tuning, is still present and useable after the packaging process.

  13. Comparison Of Effect Of Addition Of Fluvoxamine Or Risperidone To Clozapine In Chronic Partially Responsive Schizophrenic Patients On Clinical Response, QTc interval And Lipid profile

    Directory of Open Access Journals (Sweden)

    Sunil Mahakalkar

    2016-07-01

    Full Text Available Objective – To study & compare the augmentation effect of addition of fluvoxamine or risperidone in chronic partially responsive schizophrenic patients receiving clozapine on clinical and laboratory parameters.Methods - A prospective, randomized, parallel, open label 12 weeks study. The schizophrenic patients, aged 20-60 years, who followed the DSM-IV diagnostic criteria and receiving clozapine therapy, showing partial response to the treatment were recruited and the study was carried out from January 2007 to June 2008. Subjects were randomized into two groups: Group A (n=28: fluvoxamine (25-50mg/day was added to clozapine (25-200mg/day & Group B (n=27: risperidone (1-5mg/day was added to clozapine therapy. The effect of drugs was assessed by PANSS, BPRS scale and ECG and lipid profile were done at 6 and 12 weeks.Result - There was significant decrease in PANSS and BPRS score in both groups.Fluvoxamine + clozapine significantly reduced PANSS score as compared to risperidone + clozapine compared to baseline and between 6 and 12 weeks. Risperidone +clozapine prolonged QTc interval (at 12 weeks and elevated serum TG, VLDL, HDL significantly at 6 and 12 weeks.Conclusion – Although addition of fluvoxamine and risperidone to clozapine are effective in management of chronic partially responsive schizophrenia on clozapine, fluvoxamine is more effective as well as safer compared to Risperidone when compared for 6 and 12 weeks in these patients.

  14. Effects of co-treatment with mirtazapine and low doses of risperidone on immobility time in the forced swimming test in mice.

    Science.gov (United States)

    Rogóż, Zofia

    2010-01-01

    The aim of the present study was to examine the effect of mirtazapine (MIR) and risperidone (an atypical antipsychotic drug), given separately or jointly, on immobility time in the forced swimming test in male C57BL/6J mice. Fluoxetine (FLU) was used as a reference drug. MIR (2.5, 5 and 10 mg/kg) and FLU (5 and 10 mg/kg), or risperidone in low doses (0.05 and 0.1 mg/kg) given alone did not change the immobility time of mice in the forced swimming test. Joint administration of MIR (5 and 10 mg/kg) or FLU (10 mg/kg) and risperidone (0.1 mg/kg) produced antidepressant-like activity in the forced swimming test. WAY100636 (a 5-HT(1A) receptor antagonist) inhibited, while yohimbine (an α(2)-adrenergic receptor antagonist) potentiated the antidepressant-like effect induced by co-administration of MIR and risperidone. Active behavior in that test did not reflect an increase in general activity, since combined administration of antidepressants and risperidone failed to enhance the locomotor activity of mice. The obtained results indicate that risperidone applied in a low dose enhances the antidepressant-like activity of MIR and that, among other mechanisms, 5-HT(1A)-, and α(2)-adrenergic receptors may play a role in this effect.

  15. Risperidone and lorazepam concomitant use in clonazepam refractory catatonia: a case report.

    Science.gov (United States)

    Grenier, Ernesto; Ryan, Molly; Ko, Elizabeth; Fajardo, Karina; John, Vineeth

    2011-12-01

    The DSM-IV recognizes catatonia as a subtype of schizophrenia characterized by at least two of the following: motor immobility, excessive motor activity not influenced by external stimuli, and peculiarities of voluntary movement. Catatonia may also occur secondary to mania, depression, or a general medical condition including encephalitis, focal neurological lesions, metabolic disturbances, and drug intoxications and withdrawals. Benzodiazepines remain the first line of treatment; up to 80% of patients respond promptly to Lorazepam challenge; failure to respond to lorazepam may be followed by electroconvulsive therapy. Atypical antipsychotics may be a new alternative in the treatment of catatonia. Successful reduction of the catatonic symptoms has been demonstrated with atypical antipsychotics. A possible mechanism of action for the efficacy of this class of drugs involves the antagonism of the 5-HT2A receptor. We are now reporting a case of treatment response to risperidone in a patient with chronic catatonia resistant to benzodiazepines.

  16. Risperidone, quetiapine and chlorpromazine may have induced priapism in an adolescent.

    Science.gov (United States)

    Baytunca, Muharrem Burak; Kose, Sezen; Ozbaran, Burcu; Erermis, Serpil

    2016-01-01

    Priapism is the prolonged, painful erection of penile tissue not accompanied by sexual arousal. Priapism has been established as a rare adverse drug reaction to drugs such as antipsychotics, psychostimulants, antidepressants, and mood stabilizers. Immediate intervention is needed to prevent destructive and irreversible complications, such as erectile dysfunction, disfigurement, inability of the penis to stay erect, and related social/emotional problems. Antipsychotic-induced priapism may result from the alpha receptor occupancy property of those drugs. We report the case of a 13-year-old suffering from attention deficit-hyperactivity disorder plus conduct disorder with priapism related to antipsychotics. Episodes occurred with risperidone plus methylphenidate, quetiapine plus methylphenidate, and chlorpromazine alone. © 2015 Japan Pediatric Society.

  17. Effectiveness, Adverse Effects and Drug Compliance of Long-Acting Injectable Risperidone in Children and Adolescents.

    Science.gov (United States)

    Ceylan, Mehmet Fatih; Erdogan, Betül; Tural Hesapcioglu, Selma; Cop, Esra

    2017-07-19

    Although the use of oral risperidone in children and adolescents has been well studied, there is little information on the intramuscular use of long-acting injectable risperidone (LAIR). The aims of this study were to investigate the effectiveness and adverse effects of LAIR in children and adolescents with conduct disorder, bipolar disorder, and schizophrenia. In total, 42 patients (age range 12-17 years) who were non-adherent to oral antipsychotic drugs, received 25 mg/day of LAIR intramuscularly every 2 weeks. The drug was administered at least four times and up to 66 times (median drug use: 9.50 times). The effectiveness and adverse effects of the treatment were examined. There was an improvement in 13 (92.8%) of the 14 patients diagnosed with bipolar disorder, in 25 (78.1%) of 32 patients diagnosed with conduct disorder and in one (50%) of two patients diagnosed with schizophrenia. Six patients had comorbid conduct disorder and bipolar disorder. Totally, 81% of the patients improved with LAIR. Weight-gain, daytime somnolence, muscle stiffness and spasms, impaired concentration, and fatigue were the most common side effects through the whole sample. Menstrual problems were common in girls. In the study, 57.1% of the patients continued to receive their injections regularly until the end of the treatment, under physician control. A total of 16.7% discontinued the treatment due to non-adherence. The LAIR treatment was terminated in 26.2% of the patients, due to weight-gain, dystonia, and galactorrhea. In children and adolescents with conduct disorder, bipolar disorder and schizophrenia who show noncompliance with oral drugs, LAIR may improve treatment compliance. LAIR is a reliable treatment in terms of its effectiveness. Weight-gain, dystonia, and galactorrhea were the adverse effects that were responsible for LAIR treatment cessation.

  18. Effect of blonanserin on cognitive and social function in acute phase Japanese schizophrenia compared with risperidone

    Directory of Open Access Journals (Sweden)

    Hori H

    2014-03-01

    Full Text Available Hikaru Hori, Kenji Yamada, Dan Kamada, Yuka Shibata, Asuka Katsuki, Reiji Yoshimura, Jun NakamuraDepartment of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Fukuoka, JapanBackground: This study aims to determine the effectiveness of blonanserin (BNS on the cognitive and social functions of patients with schizophrenia compared with risperidone (RIS during acute-phase (8-week treatment.Methods: A total of 39 schizophrenia inpatients were included in this study. The subjects received either BNS (N=20 or RIS (N=19, and the clinical responses were evaluated periodically. The concomitant use of mood stabilizers was not allowed. Efficacy was assessed with the Positive and Negative Syndrome Scale for schizophrenia. Cognition was assessed using the Brief Assessment of Cognition in Schizophrenia, Japanese-language version. Social function was assessed using the Life Assessment Scale for the Mentally Ill.Results: For both groups, each assessment exhibited a decrease in the mean change from baseline on the Positive and Negative Syndrome Scale. The depression subscale was significantly improved in the BNS group compared with the RIS group at 8 weeks after administration. BNS improved verbal fluency and executive function (cognitive function and daily living and work skills (social function. Compared with the RIS group, BNS was observed to improve daily living.Conclusion: BNS may improve psychotic symptoms, cognitive function, and daily living in patients with acute-phase schizophrenia. BNS may be superior to RIS in the improvement of daily living.Keywords: risperidone, blonanserin, schizophrenia, cognitive function, social function, acute-phase

  19. Preparation of Hollow Silica Microspheres via Poly(N-isopropylacrylamide)

    Institute of Scientific and Technical Information of China (English)

    Mo-zhen Wang; Yu-chen Chen; Xue-ping Ge; Xue-wu Ge

    2012-01-01

    Core-shell structured SiO2/poly(N-isopropylacrylamide) (SiO2/PNIPAM) microspheres were successfully fabricated through hydrolysis and condensation reaction of tertraethyl orthosilicate (TEOS) on the surface of PNIPAM template at 50 ℃.The PNIPAM template can be easily removed by water at room temperature so that SiO2 hollow microspheres were finally obtained.The transmission electron microscope and scanning electron microscope observations indicated that SiO2 hollow microspheres with an average diameter of 150 nm can be formed only if there are enough concentration of PNIPAM and TEOS,and the hydrolysis time of TEOS.FTIR analysis showed that part of PNIPAM remained on the wall of SiO2 because of the strong interaction between PNIPAM and silica.This work provides a clean and efficient way to prepare hollow microspheres.

  20. MULTI-SCALE STRUCTURES IN EMULSION AND MICROSPHERE COMPLEX SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Guanghui Ma; Fangling Gong; Guohua Hu; Dongxia Hao; Rong Liu; Renwei Wang

    2005-01-01

    Multi-scale structures involved in emulsion and microsphere complex systems are presented and discussed. The stability and spatio-temporal structures of emulsions, as well as nano-structures formed on the surface of microspheres after polymerization, are affected by the molecular emulsifier/stabilizer structures and the adsorbed emulsifier/stabilizer nano-structures on the oil/water interface. The broad size distribution and variation of surface features of droplets are responsible for variations of the adsorbed emulsifier/stabilizer structures and the stability of the emulsions.On the other hand, preparation of a uniformly sized emulsion and employment of a combined emulsifier/stabilizer system can preserve the stability of the emulsions and microspheres. The above phenomena should be modeled by a multiscale method, in order to maintain the stability of individual emulsion systems and realize the desired nano-structures of microspheres by choosing adequate emulsifier/stabilizer and experimental parameters.

  1. Super-Resolution Real Imaging in Microsphere-Assisted Microscopy

    Science.gov (United States)

    Wang, Feifei; Li, Yi; Jia, Boliang; Liu, Lianqing; Li, Wen Jung

    2016-01-01

    Microsphere-assisted microscopy has received a lot of attention recently due to its simplicity and its capability to surpass the diffraction limit. However, to date, sub-diffraction-limit features have only been observed in virtual images formed through the microspheres. We show that it is possible to form real, super-resolution images using high-refractive index microspheres. Also, we report on how changes to a microsphere’s refractive index and size affect image formation and planes. The relationship between the focus position and the additional magnification factor is also investigated using experimental and theoretical methods. We demonstrate that such a real imaging mode, combined with the use of larger microspheres, can enlarge sub-diffraction-limit features up to 10 times that of wide-field microscopy’s magnification with a field-of-view diameter of up to 9 μm. PMID:27768774

  2. XPS analysis of aluminosilicate microspheres bioactivity tested in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Todea, M.; Vanea, E. [Faculty of Physics and Institute of Interdisciplinary Research on Bio-Nano-Sciences, Babes Bolyai University, Cluj-Napoca 400084 (Romania); Bran, S. [University of Medicine and Pharmacy “Iuliu Haţieganu”, Department of Cranio-Maxillofacial Surgery, 400029 Cluj-Napoca (Romania); Berce, P. [Technical University of Cluj-Napoca, Faculty of Machine Building and National Centre of Rapid Prototyping, 400641 Cluj-Napoca (Romania); Simon, S., E-mail: simons@phys.ubbcluj.ro [Faculty of Physics and Institute of Interdisciplinary Research on Bio-Nano-Sciences, Babes Bolyai University, Cluj-Napoca 400084 (Romania)

    2013-04-01

    The study aims to characterize surface properties of aluminosilicate microspheres incorporating yttrium, with potential biomedical applications. Micrometric particles of spherical shape were obtained by spray drying method. The behavior of aluminosilicate microspheres without yttrium and with yttrium was investigated under in vitro conditions, by seven days incubation in simulated body fluid (SBF). The surface elemental composition and the atomic environments on outermost layer of the microspheres, prior to and after incubation in SBF were evaluated by X-ray photoelectron spectroscopy (XPS) in order to investigate their bioactivity. The results were analyzed to underline the effect of yttrium addition on surface properties of the aluminosilicate microspheres and implicitly on the behavior of the samples in simulated body environments.

  3. BIOCOMPATIBLE FLUORESCENT MICROSPHERES: SAFE PARTICLES FOR MATERIAL PENETRATION STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Farquar, G; Leif, R

    2009-07-15

    Biocompatible polymers with hydrolyzable chemical bonds have been used to produce safe, non-toxic fluorescent microspheres for material penetration studies. The selection of polymeric materials depends on both biocompatibility and processability, with tailored fluorescent properties depending on specific applications. Microspheres are composed of USFDA-approved biodegradable polymers and non-toxic fluorophores and are therefore suitable for tests where human exposure is possible. Micropheres were produced which contain unique fluorophores to enable discrimination from background aerosol particles. Characteristics that affect dispersion and adhesion can be modified depending on use. Several different microsphere preparation methods are possible, including the use of a vibrating orifice aerosol generator (VOAG), a Sono-Tek atomizer, an emulsion technique, and inkjet printhead. Applications for the fluorescent microspheres include challenges for biodefense system testing, calibrants for biofluorescence sensors, and particles for air dispersion model validation studies.

  4. Amorphous and nanostructured silica and aluminosilicate spray-dried microspheres

    Science.gov (United States)

    Todea, M.; Turcu, R. V. F.; Frentiu, B.; Tamasan, M.; Mocuta, H.; Ponta, O.; Simon, S.

    2011-08-01

    Amorphous silica and aluminosilicate microspheres with diameters in the 0.1-20 μm range were produced by spray drying method. SEM, TEM and AFM images showed the spherical shape of the obtained particles. Based on thermal analysis data, several heat treatments have been applied on the as-prepared samples in order to check the amorphous state stability of the microspheres and to develop nanosized crystalline phases. As-prepared microspheres remain amorphous up to 1400 °C. By calcination at 1400 °C, cristobalite type nanocrystals are developed on silica sample, while in aluminosilicate sample first are developed mullite type nanocrystals and only after prolonged treatment are developed also cristobalite type nanocrystals. 29Si and 27Al MAS NMR results show that the local order around aluminum and silicon atoms strongly depend on the thermal history of the microspheres.

  5. Resonant microsphere gyroscope based on a double Faraday rotator system.

    Science.gov (United States)

    Xie, Chengfeng; Tang, Jun; Cui, Danfeng; Wu, Dajin; Zhang, Chengfei; Li, Chunming; Zhen, Yongqiu; Xue, Chenyang; Liu, Jun

    2016-10-15

    The resonant microsphere gyroscope is proposed based on a double Faraday rotator system for the resonant microsphere gyroscope (RMSG) that is characterized by low insertion losses and does not destroy the reciprocity of the gyroscope system. Use of the echo suppression structure and the orthogonal polarization method can effectively inhibit both the backscattering noise and the polarization error, and reduce them below the system sensitivity limit. The resonance asymmetry rate dropped from 34.2% to 2.9% after optimization of the backscattering noise and the polarization noise, which greatly improved the bias stability and the scale factor linearity of the proposed system. Additionally, based on the optimum parameters for the double Faraday rotator system, a bias stability of 0.04°/s has been established for an integration time of 10 s in 1000 s in a resonator microsphere gyroscope using a microsphere resonator with a diameter of 1 mm and a Q of 7.2×106.

  6. Development and characterization of ethylcellulose based microsphere for sustained release of nifedipine$

    Institute of Scientific and Technical Information of China (English)

    Patitapabana Parida; Subash Chandra Mishra; Subhashree Sahoo; Ajit Behera; Bibhukalyan Prasad Nayak

    2016-01-01

    This article introduced the work of ethylcellulose based polymeric microsphere loaded with nifedipine for reduction in frequency of administration with low solubility in aqueous medium and high rate of absorption in the stomach. The non-aqueous polymeric suspension was put dropwise into an aqueous medium containing polyvinyl alcohol as a surfactant for the synthesis of microsphere by solvent eva-poration. The microspheres were characterized by different techniques, namely, XRD, SEM, and NMR. The formation of microspheres was confirmed by SEM. XRD analysis revealed the semi-crystallinity nature of microspheres. The NMR study indicated the presence of hetero-aromatic nucleus in the microsphere.

  7. Preparation of biodegradable microspheres and matrix devices containing naltrexone

    OpenAIRE

    DINARVAND, RASSOUL; Moghadam, Shadi H.; Mohammadyari-Fard, Leyla; Atyabi, Fatemeh

    2003-01-01

    In this study, the use of biodegradable polymers for microencapsulation of naltrexone using solvent evaporation technique is investigated. The use of naltrexone microspheres for the preparation of matrix devices is also studied. For this purpose, poly(L-lactide) (PLA) microspheres containing naltrexone prepared by solvent evaporation technique were compressed at temperatures above the Tg of the polymer. The effect of different process parameters, such as drug/polymer ratio and stirring rate d...

  8. In vitro and in vivo toxicity of magnetic microspheres

    Science.gov (United States)

    Häfeli, Urs O.; Pauer, Gayle J.

    1999-04-01

    The interaction of magnetic microspheres with cells was studied using an in vitro 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide (=MTT) assay. Viability and metabolic activity were reduced in all examples. The MTT assay is not recommended for this application due to high variability and non-specificity. Poly(lactic acid) microspheres were further tested in vivo. Intrathecal injection in rats produced no obvious side effects over 12 months.

  9. Multiplexed magnetic microsphere immunoassays for detection of pathogens in foods

    OpenAIRE

    Kim, Jason S.; Chris R Taitt; Ligler, Frances S.; Anderson, George P.

    2010-01-01

    Foodstuffs have traditionally been challenging matrices for conducting immunoassays. Proteins, carbohydrates, and other macromolecules present in food matrices may interfere with both immunoassays and PCR-based tests, and removal of particulate matter may also prove challenging prior to analyses. This has been found true when testing for bacterial contamination of foods using the standard polystyrene microspheres utilized with Luminex flow cytometers. Luminex MagPlex microspheres are encoded ...

  10. CHARACTERIZATION OF CAPTOPRIL-ETHYL CELLULOSE MICROSPHERES BY THERMAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    RakeshGupta

    2010-06-01

    Full Text Available The objective of the present study was to study the physical characterization of Captopril-ethyl cellulose microspheres by thermal analysis such as Differential Scanning Calorimetry (DSC, Differential thermal analysis (DTA and Thermo gravimetry (TG. Drug polymer interaction can directly affect the dosage form stability, drug encapsulation into polymers and dissolution patterns. In this study thermal analysis has been carried out for the physical mixtures and microspheres of captopril and ethyl cellulose prepared by solvent evaporation method.

  11. Study of mucoadhesive microsphere of pirfenidone for nasal drug delivery

    Directory of Open Access Journals (Sweden)

    Vrushali Kashikar

    2014-01-01

    Full Text Available The present research work involves formulation development and evaluation of nasal mucoadhesive microsphere in view to, improve bioavailability and reduce dosing regimen. Microspheres were prepared by spray drying and cross-linking method using chitosan and HPMC K4M, using 32 central composite design. Microspheres were evaluated for particle size, drug content, swelling ability, and percentage yield. Compatibility was checked by doing Fourier transform infrared spectroscopy and Differential scanning calorimetry study. The polymorphism and particle shape were studied by X-ray diffraction and scanning electron microscopy. The average particle size of spray-dried and cross-linked formulations were found in the range between 20-50 μm and 30-60 μm with percent mucoadhesion in the range of 80%-90% and 60-70%, respectively. In vitro drug release was found to be proportional to drug to polymer ratio. In vitro drug release for optimized formulation, that is, (F1, for spray-drying method and cross-linking method was found to be 88.73% and 70.93% at the end of 6 h, respectively. Release of drug from microspheres followed non-Fickian diffusion kinetics. Ex vivo studies were performed with sheep nasal mucosa for mucoadhesion, histopathological study, and drug permeation. The histopathological study indicates nonirritant nature of microsphere. The microspheres were found to be stable at accelerated storage conditions for 1 month, as per International Conference of Harmonisation guidelines.

  12. Inherently fluorescent polystyrene microspheres for coating, sensing and cellular imaging.

    Science.gov (United States)

    Qu, Jian-Bo; Xu, Yu-Liang; Liu, Yu; Wang, Yanan; Sui, Yuanhong; Liu, Jian-Guo; Wang, Xiaojuan

    2017-04-01

    Commercially available polystyrene (PS) fluorescent microspheres are widely used in biological field for tracing, in vivo imaging and calibration of flow cytometry, among other applications. However, these particles do suffer from some drawbacks such as the leakage and photobleaching of organic dyes within them. In the present study, inherently fluorescent properties of PS based microspheres have been explored for the first time. Here we find that a simple chloromethylation reaction endows the polystyrene particles with inherent fluorescence without any subsequent conjugation of an external fluorophore. A possible mechanism for fluorescence is elucidated by synthesizing and investigating p-ethylbenzyl chloride, a compound with similar structure. Significantly, no photobleaching or leaking issues were observed owing to the stable structure of the microspheres. Chloromethylated PS (CMPS) microspheres can keep their perpetual blue fluorescence even in dry powder state making them attractive as a potential coating material. Furthermore, the chloromethyl groups on CMPS microspheres make them very convenient for further functionalization. Poly(ethylene glycol) (PEG) grafted microspheres showed good biocompatibility and negligible cytotoxicity, and could be used to image intracellular Fe(3+) due to the selective fluorescence quenching effect of aqueous Fe(3+) in cytoplasm.

  13. Mucoadhesive microspheres prepared by interpolymer complexation and solvent diffusion method.

    Science.gov (United States)

    Chun, Myung-Kwan; Cho, Chong-Su; Choi, Hoo-Kyun

    2005-01-20

    Mucoadhesive microspheres were prepared to increase gastric residence time using an interpolymer complexation of poly(acrylic acid) (PAA) with poly(vinyl pyrrolidone) (PVP) and a solvent diffusion method. The complexation between poly(acrylic acid) and poly(vinyl pyrrolidone) as a result of hydrogen bonding was confirmed by the shift in the carbonyl absorption bands of poly(acrylic acid) using FT-IR. A mixture of ethanol/water was used as the internal phase, corn oil was used as the external phase of emulsion, and span 80 was used as the surfactant. Spherical microspheres were prepared and the inside of the microspheres was completely filled. The optimum solvent ratio of the internal phase (ethanol/water) was 8/2 and 7/3, and the particle size increased as the content of water was increased. The mean particle size increased with the increase in polymer concentration. The adhesive force of microspheres was equivalent to that of Carbopol. The release rate of acetaminophen from the complex microspheres was slower than the PVP microspheres at pH 2.0 and 6.8.

  14. Validity of microsphere depositions for regional myocardial flows

    Energy Technology Data Exchange (ETDEWEB)

    Bassingthwaighte, J.B.; Malone, M.A.; Moffett, T.C.; King, R.B.; Little, S.E.; Link, J.M.; Krohn, K.A.

    1987-07-01

    Due to the particulate nature of microspheres, their deposition in small-tissue regions may not be strictly flow dependent. To evaluate the importance of rheological and geometric factors and random error, their deposition densities in small regions of rabbit hearts were examined in comparison with those of a new molecular microsphere, 2-iododesmethylimipramine (IDMI), whose high lipid solubility allows it to be delivered into tissue in proportion to flow, and whose binding in tissue prevents rapid washout. /sup 141/Ce- and /sup 103/Ru-labeled 16.5-..mu..m spheres in one syringe and (/sup 125/I)- and (/sup 131/I)DMI in another syringe were injected simultaneously into the left atrium of open-chest rabbits, while obtaining reference blood samples from the femoral artery. Hearts were removed 1 min after injection, cut into /approximately/ 100 pieces averaging 54 mg, and the regional deposition densities calculated for each tracer from the isotopic counts. Scatter plots of sphere densities vs. IDMI densities showed that differences between microspheres and IDMI had substantial scatter and were not random. Microsphere depositions tended to be lower that IDMI deposition at low flows and higher at high flows. The authors conclude that microspheres are generally adequate for estimating regional flows but suffer systematic error when the regions of interest are supplied via arteries of diameters only a few times those of microspheres.

  15. Microspheres and Nanotechnology for Drug Delivery.

    Science.gov (United States)

    Jóhannesson, Gauti; Stefánsson, Einar; Loftsson, Thorsteinn

    2016-01-01

    Ocular drug delivery to the posterior segment of the eye can be accomplished by invasive drug injections into different tissues of the eye and noninvasive topical treatment. Invasive treatment involves the risks of surgical trauma and infection, and conventional topical treatments are ineffective in delivering drugs to the posterior segment of the eye. In recent years, nanotechnology has become an ever-increasing part of ocular drug delivery. In the following, we briefly review microspheres and nanotechnology for drug delivery to the eye, including different forms of nanotechnology such as nanoparticles, microparticles, liposomes, microemulsions and micromachines. The permeation barriers and anatomical considerations linked to ocular drug delivery are discussed and a theoretical overview on drug delivery through biological membranes is given. Finally, in vitro, in vivo and human studies of x03B3;-cyclodextrin nanoparticle eyedrop suspensions are discussed as an example of nanotechnology used for drug delivery to the eye.

  16. Nonstationary photonic jet from dielectric microsphere

    CERN Document Server

    Geints, Yu; Zemlyanov, A

    2014-01-01

    A photonic jet commonly denotes the specific spatially localized region in the near-field forward scattering of a light wave at a dielectric micron-sized particle. We present the detailed calculations of the transient response of an airborne silica microsphere illuminated by a femtosecond laser pulse. The spatial area constituting the photonic jet is theoretically investigated and the temporal dynamics of jet dimensions as well as of jet peak intensity is analyzed. The role of morphology-dependent resonances in jet formation is highlighted. The evolution scenario of a nonstationary photonic jet generally consists of the non-resonant and resonant temporal phases. In every phase, the photonic jet can change its spatial form and intensity.

  17. Thermal analysis of SYNROC gel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Knipschild, K.E.; Lee, D.A.

    1981-11-01

    Thermoanalytical methods were used to characterize SYNROC microspheres at three stages of the internal gelation process: unwashed spheres, washed spheres, and washed-and-dried spheres. Linear-programmed heating experiments were performed using thermogravimetric analysis, differential scanning calorimetry, differential thermal analysis, and mass spectrometry for producing the thermograms. The data were used to elucidate thermal reactions occurring between ambient and 800/sup 0/C. The principal reactions were the release of waters from various sources, the decomposition and combustion of gelation additives (hexamethylenetetramine and urea), and the decomposition of carbonates. Data also demonstrated the efficiency of the washing process. Kinetic studies were carried out by differential scanning calorimetry and differential thermal analysis to determine activation energies for certain pyrolysis reactions. 8 figures.

  18. Permeability of Hollow Microspherical Membranes to Helium

    Science.gov (United States)

    Zinoviev, V. N.; Kazanin, I. V.; Pak, A. Yu.; Vereshchagin, A. S.; Lebiga, V. A.; Fomin, V. M.

    2016-01-01

    This work is devoted to the study of the sorption characteristics of various hollow microspherical membranes to reveal particles most suitable for application in the membrane-sorption technologies of helium extraction from a natural gas. The permeability of the investigated sorbents to helium and their impermeability to air and methane are shown experimentally. The sorption-desorption dependences of the studied sorbents have been obtained, from which the parameters of their specific permeability to helium are calculated. It has been established that the physicochemical modification of the original particles exerts a great influence on the coefficient of the permeability of a sorbent to helium. Specially treated cenospheres have displayed high efficiency as membranes for selective extraction of helium.

  19. Con-A conjugated mucoadhesive microspheres for the colonic delivery of diloxanide furoate.

    Science.gov (United States)

    Anande, Nalini M; Jain, Sunil K; Jain, Narendra K

    2008-07-01

    The aim of the research work was to develop cyst-targeted novel concanavalin-A (Con-A) conjugated mucoadhesive microspheres of diloxanide furoate (DF) for the effective treatment of amoebiasis. Eudragit microspheres of DF were prepared using emulsification-solvent evaporation method. Formulations were characterized for particle size and size distribution, % drug entrapment, surface morphology and in vitro drug release in simulated gastrointestinal (GI) fluids. Eudragit microspheres of DF were conjugated with Con-A. IR spectroscopy and DSC were used to confirm successful conjugation of Con-A to Eudragit microspheres while Con-A conjugated microspheres were further characterized using the parameters of zeta potential, mucoadhesiveness to colonic mucosa and Con-A conjugation efficiency with microspheres. IR studies confirmed the attachment of Con-A with Eudragit microspheres. All the microsphere formulations showed good % drug entrapment (78+/-5%). Zeta potential of Eudragit microspheres and Con-A conjugated Eudragit microspheres were found to be 3.12+/-0.7mV and 16.12+/-0.5mV, respectively. Attachment of lectin to the Eudragit microspheres significantly increases the mucoadhesiveness and also controls the release of DF in simulated GI fluids. Gamma scintigraphy study suggested that Eudragit S100 coated gelatin capsule retarded the release of Con-A conjugated microspheres at low pH and released microspheres slowly at pH 7.4 in the colon.

  20. Risperidone-induced polydipsia and polyphagia associated with galactorrhea, abdominal pain, and rapid weight gain in an adolescent Hispanic female.

    Science.gov (United States)

    Afzal, Khalid I; Briones, David F; DeVargas, Cecilia

    2007-11-01

    A 15-year-old Hispanic female was started on risperidone for new-onset psychosis. The patient responded well to the gradual dose increase but developed rapid weight gain secondary to polydipsia and polyphagia. She also began complaining of nipple discharge and griping abdominal pain on the left lower quadrant by the third week of treatment. Her prolactin level escalated to three times normal with a weight gain of 12 pounds in 16 days. Risperidone was switched to another antipsychotic. Her prolactin level then dropped to a normal level within 7 days and she lost 7 pounds in the next 2 weeks. Her abdominal pain, galactorrhea, polydipsia, and polyphagia subsided within the first few days of the cessation of risperdione.

  1. Effects of Environmental Manipulations and Treatment with Bupropion and Risperidone on Choice between Methamphetamine and Food in Rhesus Monkeys.

    Science.gov (United States)

    Banks, Matthew L; Blough, Bruce E

    2015-08-01

    Preclinical and human laboratory choice procedures have been invaluable in improving our knowledge of the neurobiological mechanisms of drug reinforcement and in the drug development process for candidate medications to treat drug addiction. However, little is known about the neuropharmacological mechanisms of methamphetamine vs food choice. The aims of this study were to develop a methamphetamine vs food choice procedure and determine treatment effects with two clinically relevant compounds: the monoamine uptake inhibitor bupropion and the dopamine antagonist risperidone. Rhesus monkeys (n=6) responded under a concurrent schedule of food delivery (1-g pellets, fixed-ratio (FR) 100 schedule) and intravenous methamphetamine injections (0-0.32 mg/kg/injection, FR10 schedule) during 7-day bupropion (0.32-1.8 mg/kg/h) and risperidone (0.001-0.0056 mg/kg/h) treatment periods. For comparison, effects of removing food pellets or methamphetamine injections and FR response requirement manipulations were also examined. Under saline treatment conditions, food was preferred over no methamphetamine or small unit methamphetamine doses (0.01-0.032 mg/kg/injection). Larger methamphetamine doses resulted in greater methamphetamine preference and 0.32 mg/kg/injection methamphetamine maintained near exclusive preference. Removing food availability increased methamphetamine choice, whereas removing methamphetamine availability decreased methamphetamine choice. Methamphetamine choice was not significantly altered when the FR response requirements for food and drug were the same (FR100:FR100 or FR10:FR10). Risperidone treatment increased methamphetamine choice, whereas bupropion treatment did not alter methamphetamine choice up to doses that decreased rates of operant behavior. Overall, these negative results with bupropion and risperidone are concordant with previous human laboratory and clinical trials and support the potential validity of this preclinical methamphetamine vs food

  2. Efficacy of Risperidone Augmentation with Ondansetron in the Treatment of Negative and Depressive Symptoms in Schizophrenia: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Roya Samadi

    2017-01-01

    Full Text Available Background: Given the potential role of the 5-hydroxytryptamine-3 receptor in the pathogenesis of schizophrenia, this study was performed to determine whether ondansetron plus risperidone could reduce the negative and depressive symptoms in patients with treatment-resistant schizophrenia. Methods: In a double-blinded, placebo-controlled, randomized trial (IRCT registration # 201112125280N7, in 2012–2013 in Mashhad, Iran, 38 patients with treatment-resistant schizophrenia received risperidone either combined with a fixed dose (4–8 mg/d of ondansetron (n=18 or with a placebo (n=20 for 12 weeks. The patients were evaluated using the Positive and Negative Syndrome Scale (PANSS, Wechsler’s Adult Intelligence Scale-Revised (WAIS-R, and Hamilton’s Rating Scale for Depression (HRSD at baseline and 12 weeks later. Changes in the inventories were used to evaluate the efficacy of the treatment. The t test, Chi-square test, and SPSS (version 16 were used to analyze the data. The statistical significance was set at P<0.05. Results: Ondansetron plus risperidone was associated with a significantly larger improvement in the PANSS overall scale and subscales for negative symptoms and cognition than was risperidone plus placebo (P<0.001. The WAIS-R scale results indicated significant differences between the 2 groups before and after administrating the medicine and the placebo. The administration of ondansetron significantly improved visual memory based on the subtests of the WAIS (P<0.05. Ondansetron had no positive effects on depressive symptoms (effect size=0.13. Conclusion: This study confirmed that ondansetron, as an adjunct treatment, reduces negative symptoms in patients with schizophrenia and can be used as a potential adjunctive strategy particularly for negative symptoms and cognitive impairments. Trial Registration Number: IRCT201112125280N7

  3. Use of a Direct Observational Measure in a Trial of Risperidone and Parent Training in Children with Pervasive Developmental Disorders

    Science.gov (United States)

    Johnson, Cynthia R.; Butter, Eric M.; Lecavalier, Luc; Scahill, Lawrence; Aman, Michael G.; McDougle, Christopher J.; Arnold, L. Eugene; Swiezy, Naomi B.; Sukhodolsky, Denis G.; Mulick, James A.; White, Susan W.; Bearss, Karen; Hollway, Jill A.; Stigler, Kimberly A.; Dziura, James; Yu, Sunkyung; Sacco, Kelley; Vitiello, Benedetto

    2013-01-01

    A Structured Observational Analog Procedure (SOAP), an analogue measure of parent-child interactions, was used to assess treatment outcome in children with Autism Spectrum Disorder and serious behavior problems. It served as a secondary outcome measure in a 24-week, randomized trial of risperidone (MED; N=49) versus risperidone plus parent training (COMB; n=75) (ages 4–13 years). At 24-weeks, there was 28 % reduction in child inappropriate behavior during a Demand Condition (p=.0002) and 12 % increase in compliance to parental requests (p=.004) for the two treatment conditions combined. Parents displayed 64 % greater use of positive reinforcement (p=.001) and fewer repeated requests for compliance (p<.0001). In the analysis of covariance (ANCOVA), COMB parents used significantly more positive reinforcement (p=.01) and fewer restrictive statements (p<.05) than MED parents. The SOAP is sensitive to change in child and parent behavior as a function of risperidone alone and in combination with PMT and can serve as a valuable complement to parent and clinician-based measures. PMID:23730123

  4. Neurotoxic syndrome induced by clomipramine plus risperidone in a patient with autistic spectrum disorder: serotonin or neuroleptic malignant syndrome?

    Science.gov (United States)

    Nikolaou, Kalliopi N; Gournellis, Rossetos; Michopoulos, Ioannis; Dervenoulas, Georgios; Christodoulou, Christos; Douzenis, Athanasios

    2015-01-01

    To the best of our knowledge, there are no case studies of serotonin syndrome (SS) in patients with autism spectrum disorder. We report the case of a 33-year-old male who presented SS under the combined use of clomipramine and risperidone. More specifically, within 2 days after clomipramine (10 mg/BID-two times a day) was added to risperidone (4 mg/OD-once a day), mirtazapine 45 mg/OD and alprazolam (0,5 mg/TID-three times a day) he began to present mental, neurological and autonomic symptoms. All his psychopathological manifestations and laboratory findings normalized after the above-mentioned drugs' discontinuation, and the administration of supportive medical care and lorazepam 2,5 mg/TID. The diagnosis of serotonin syndrome was challenging due to the relatively low dose of clomipramine, an increase of risperidone which had taken place before clomipramine administration and clinical symptoms which could be attributed to both serotonin and neuroleptic malignant syndrome.

  5. Low-Dose Atypical Antipsychotic Risperidone Improves the 5-Year Outcome in Alzheimer's Disease Patients with Sleep Disturbances.

    Science.gov (United States)

    Yin, You; Liu, Yan; Zhuang, Jianhua; Pan, Xiao; Li, Peng; Yang, Yuechang; Li, Yan-Peng; Zhao, Zheng-Qing; Huang, Liu-Qing; Zhao, Zhong-Xin

    2015-01-01

    Sleep disturbances (SD) accelerate the progression of Alzheimer's disease (AD) and increase the stress of caregivers. However, the long-term outcome of disturbed nocturnal sleep/wake patterns in AD and on increased stress of spousal caregivers is unclear. This study assessed the 5-year effect of nocturnal SD on the long-term outcome in AD patients. A total of 156 donepezil-treated mild-moderate AD patients (93 AD + SD and 63 AD - SD as a control group) were recruited. The AD + SD patients were formed into 4 subgroups according to the preferences of spousal caregivers for treatment with atypical antipsychotics (0.5-1 mg risperidone, n = 22), non-benzodiazepine hypnotic (5-10 mg zolpidem tartrate, n = 33), melatonin (2.55 mg, n = 9), or no-drug treatment (n = 29). SD were evaluated by polysomnography, sleep scale, and cognitive scale examinations. Moreover, all spousal caregivers of AD patients were assessed using a series of scales, including sleep, anxiety, mood, and treatment attitude scales. Our data showed that nocturnal sleep/wake disturbances were significantly associated with lower 5-year outcomes for AD patients, earlier nursing home placement, and more negative emotions of spousal caregivers. Treatment with low-dose atypical antipsychotic risperidone improved the 5-year outcome in AD + SD patients. In conclusion, low-dose atypical antipsychotic risperidone improves the 5-year outcome in AD patients with SD. Moreover, improvement of nocturnal sleep problems in AD patients will also bring better emotional stability for AD caregivers.

  6. Demagnetization treatment of remanent composite microspheres studied by alternating current susceptibility measurements

    NARCIS (Netherlands)

    van Berkum, S.; Erné, B.H.

    2013-01-01

    The magnetic remanence of silica microspheres with a low concentration of embedded cobalt ferrite nanoparticles is studied after demagnetization and remagnetization treatments. When the microspheres are dispersed in a liquid, alternating current (AC) magnetic susceptibility spectra reveal a constant

  7. In Vitro Cytotoxicity and Protein Drug Release Properties of Chitosan/Heparin Microspheres

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Chitosan/heparin microspheres were prepared using the water-in-oil emulsification solvent evaporation technique. The microsphere diameters were controlled by selecting the fabrication process parameters. Scanning electron micrographs showed that the chitosan/heparin microspheres were regular and the surface morphology was smooth. Fourier transform infrared showed that the chitosan amino groups reacted with heparin carboxylic groups to form acylamides in the microspheres. Analysis of the microsphere cytotoxicity showed that they had no cytotoxic effect and behaved very similar to the negative control (polystyrene).To analyze the protein drug release profiles of the microspheres, bovine serum albumin was loaded as a model drug into the microspheres and released in vitro. Marked retardation was observed in the BSA release profiles. The results show that chitosan/heparin microspheres may provide a useful controlled release protein drug system for used in pharmaceutics.

  8. Preparation of polysulfone hollow microspheres encapsulating DNA and their functional utilization.

    Science.gov (United States)

    Zhao, C; Liu, X D; Nomizu, M; Nishi, N

    2004-05-01

    Polysulfone hollow microspheres encapsulating DNA were prepared using a liquid-liquid phase separation technique. The microspheres were then used to absorb a DNA-binding intercalating material--ethidium bromide. The amount of DNA encapsulated in the microspheres depended on the concentration of the DNA solution used to prepare the microspheres, and the microsphere morphology depended on both the polymer concentration and the preparation conditions. The amount of ethidium bromide in the microspheres depended mainly on the amount of encapsulated DNA, and the microsphere morphology also affected the removal of the ethidium bromide. The new method of DNA encapsulation is proposed, and the microspheres encapsulating the DNA have the potential to be used in environmental applications.

  9. Fabrication and characterization of porous hydroxyapatite microspheres by spray-drying method

    Institute of Scientific and Technical Information of China (English)

    Rui-xue SUN; Yu-peng LU

    2008-01-01

    In the present paper, porous hydroxyapatite (HA) microspheres were fabricated using gelatin as a pore-forming agent by spray-drying method. The mean particle size of the microspheres is about 7 μm and the surface area is about 53.4 m2/g. The experimental results showed that the porosity of the prepared microspheres is higher and the pores are more interconnected compared with the microspheres obtained without any additives.

  10. Silica Microspheres Are Superior to Polystyrene for Microvesicle Analysis by Flow Cytometry

    Science.gov (United States)

    2015-02-16

    Regular Article Silica microspheres are superior to polystyrene for microvesicle analysis by flow cytometry☆ Bijaya Kumar Parida ⁎, Hiram Garrastazu...February 2015 Available online 16 February 2015 Keywords: Microvesicles Cell-derived microparticles Silica microspheres Polystyrene microspheres ...is used to characterize MVs. Polystyrene microspheres are often used in flow cytometry to distinguish MV from cells by setting a 1-μm MV gate in a

  11. Preparation of Dysprosium Ferrite/Polyacrylamide Magnetic Composite Microsphere and Its Characterization

    Institute of Scientific and Technical Information of China (English)

    Hidehiro Kumazawa; Wang Zhifeng; Zhou Lanxiang; Zhang Hong; Li Yourong; Zhang Ming

    2005-01-01

    Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure, average particle size, morphology of composite microsphere were characterized by FTIR, XRD, TEM and TGA. The magnetic responsibility of composite microsphere was also investigated. The results indicate that the magnetic composite microsphere possess high magnetic responsibility and suspension stability.

  12. The synthesis and photocatalytic activity of ZnSe microspheres.

    Science.gov (United States)

    Cao, Huaqiang; Xiao, Yujiang; Zhang, Sichun

    2011-01-07

    This paper reports the synthesis of semiconductor ZnSe microspheres composed of nanoparticles via a solvothermal route between the organic molecule selenophene (C(4)H(4) Se) and ZnCl(2) without adding any surfactant. The ZnSe microspheres were characterized by x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), specific surface area measurement, and photoluminescence (PL) spectra. A strong and broad blue PL emission at 443 nm in wavelength (∼2.79 eV in photon energy) is attributed to the near-band-edge (NBE) emission of ZnSe, while the 530 nm peak is a defect-related (DL) emission. The photocatalytic activity of the as-prepared ZnSe microspheres was evaluated by photodegradation of methyl orange (MO) dye under ultraviolet (UV) light and visible light irradiation. The degradations of MO reach 94% or 95.1%, close to 100%, in the presence of the as-synthesized ZnSe microspheres or commercial ZnSe powder after 7 or 10 h under UV irradiation, respectively. Meanwhile the degradations of MO reach 94.3% or 60.6% in the presence of the as-synthesized ZnSe microspheres or commercial ZnSe powder after 12 h, respectively. The degradation rate of ZnSe microspheres is twice that of ZnSe commercial powder under UV light irradiation, and three times under visible light irradiation. The degradation process of MO dye on ZnSe microspheres under UV or visible light is also discussed.

  13. The synthesis and photocatalytic activity of ZnSe microspheres

    Science.gov (United States)

    Cao, Huaqiang; Xiao, Yujiang; Zhang, Sichun

    2011-01-01

    This paper reports the synthesis of semiconductor ZnSe microspheres composed of nanoparticles via a solvothermal route between the organic molecule selenophene (C4H4 Se) and ZnCl2 without adding any surfactant. The ZnSe microspheres were characterized by x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), specific surface area measurement, and photoluminescence (PL) spectra. A strong and broad blue PL emission at 443 nm in wavelength (~2.79 eV in photon energy) is attributed to the near-band-edge (NBE) emission of ZnSe, while the 530 nm peak is a defect-related (DL) emission. The photocatalytic activity of the as-prepared ZnSe microspheres was evaluated by photodegradation of methyl orange (MO) dye under ultraviolet (UV) light and visible light irradiation. The degradations of MO reach 94% or 95.1%, close to 100%, in the presence of the as-synthesized ZnSe microspheres or commercial ZnSe powder after 7 or 10 h under UV irradiation, respectively. Meanwhile the degradations of MO reach 94.3% or 60.6% in the presence of the as-synthesized ZnSe microspheres or commercial ZnSe powder after 12 h, respectively. The degradation rate of ZnSe microspheres is twice that of ZnSe commercial powder under UV light irradiation, and three times under visible light irradiation. The degradation process of MO dye on ZnSe microspheres under UV or visible light is also discussed.

  14. A novel strategy for the preparation of porous microspheres and its application in peptide drug loading.

    Science.gov (United States)

    Wei, Yi; Wang, Yuxia; Zhang, Huixia; Zhou, Weiqing; Ma, Guanghui

    2016-09-15

    A new strategy is developed to prepare porous microspheres with narrow size distribution for peptides controlled release, involving a fabrication of porous microspheres without any porogens followed by a pore closing process. Amphiphilic polymers with different hydrophobic segments (poly(monomethoxypolyethylene glycol-co-d,l-lactide) (mPEG-PLA), poly(monomethoxypolyethylene glycol-co-d,l-lactic-co-glycolic acid) (mPEG-PLGA)) are employed as microspheres matrix to prepare porous microspheres based on a double emulsion-premix membrane emulsification technique combined with a solvent evaporation method. Both microspheres possess narrow size distribution and porous surface, which are mainly caused by (a) hydrophilic polyethylene glycol (PEG) segments absorbing water molecules followed by a water evaporation process and (b) local explosion of microspheres due to fast evaporation of dichloromethane (MC). Importantly, mPEG-PLGA microspheres have a honeycomb like structure while mPEG-PLA microspheres have a solid structure internally, illustrating that the different hydrophobic segments could modulate the affinity between solvent and matrix polymer and influence the phase separation rate of microspheres matrix. Long term release patterns are demonstrated with pore-closed microspheres, which are prepared from mPEG-PLGA microspheres loading salmon calcitonin (SCT). These results suggest that it is potential to construct porous microspheres for drug sustained release using permanent geometric templates as new porogens.

  15. Real time monitoring of coating status for microsphere target with digital image difference method

    Institute of Scientific and Technical Information of China (English)

    Baixuan Shi(施柏煊); Xiao Huang(黄晓); Caifeng Li(李彩凤)

    2003-01-01

    Digital image difference method monitorring coating status of microsphere targets automatically is sug-gested. A CCD micro-imaging system is developed for monitoring the status of bouncing and adherencebetween microspheres and the bouncing pan. A new bouncing pan with multiple holes is adopted formicrosphere coating to enhance the microsphere coating efficiency.

  16. PLGA microsphere/calcium phosphate cement composites for tissue engineering: in vitro release and degradation characteristics.

    NARCIS (Netherlands)

    Habraken, W.J.E.M.; Wolke, J.G.C.; Mikos, A.G.; Jansen, J.A.

    2008-01-01

    Bone cements with biodegradable poly(lactic-co-glycolic acid) (PLGA) microspheres have already been proven to provide a macroporous calcium phosphate cement (CPC) during in situ microsphere degradation. Furthermore, in vitro/in vivo release studies with these PLGA microsphere/CPC composites (PLGA/CP

  17. Maintenance therapy with once-monthly administration of long-acting injectable risperidone in patients with schizophrenia or schizoaffective disorder: a pilot study of an extended dosing interval

    Directory of Open Access Journals (Sweden)

    Naessens Ineke

    2007-01-01

    Full Text Available Abstract Background Several clinical studies have established the efficacy, safety, and tolerability of long-acting risperidone administered once every 2 weeks in patients with schizophrenia or schizoaffective disorder. This report evaluates preliminary efficacy, safety, tolerability, and pharmacokinetic data for a novel (once-monthly administration of long-acting injectable risperidone 50 mg in patients with schizophrenia or schizoaffective disorder. Methods Clinically stable patients participated in a 1-year, open-label, single-arm, multicenter pilot study. During the 4-week lead-in phase, patients received long-acting risperidone 50 mg injections every 2 weeks, with 2 weeks of oral risperidone supplementation. Injections of long-acting risperidone 50 mg every 4 weeks followed for up to 48 weeks, without oral supplementation. The primary endpoint was relapse; other assessments included PANSS, CGI-S, adverse event reports, and determination of risperidone and 9-hydroxyrisperidone plasma concentrations. Results Twelve patients in the intent-to-treat population (n = 67 met relapse criteria (17.9%. Relapse risk at 1 year was estimated as 22.4%. Non-statistically significant improvements in symptoms (PANSS and clinical status (CGI-S at endpoint were observed. The most common adverse events included schizophrenia aggravated not otherwise specified (19.5%, anxiety (16.1%, insomnia (16.1%, and headache (11.5%. There were no unexpected safety and tolerability findings. Mean plasma concentrations for risperidone and 9-hydroxyrisperidone were generally stable during the study. Conclusion Once-monthly dosing of long-acting risperidone was well tolerated, associated with a relatively low relapse rate (similar to that reported with other antipsychotics, and maintained the clinically stable baseline status of most patients. Although the results suggest that some symptomatically stable patients with schizophrenia or schizoaffective disorder might be safely

  18. Adjunctive risperidone treatment for antidepressant-resistant symptoms of chronic military service-related PTSD: a randomized trial.

    Science.gov (United States)

    Krystal, John H; Rosenheck, Robert A; Cramer, Joyce A; Vessicchio, Jennifer C; Jones, Karen M; Vertrees, Julia E; Horney, Rebecca A; Huang, Grant D; Stock, Christopher

    2011-08-03

    Serotonin reuptake-inhibiting (SRI) antidepressants are the only FDA-approved pharmacotherapies for the treatment of posttraumatic stress disorder (PTSD). To determine efficacy of the second-generation antipsychotic risperidone as an adjunct to ongoing pharmacologic and psychosocial treatments for veterans with chronic military-related PTSD. A 6-month, randomized, double-blind, placebo-controlled multicenter trial conducted between February 2007 and February 2010 at 23 Veterans Administration outpatient medical centers. Of the 367 patients screened, 296 were diagnosed with military-related PTSD and had ongoing symptoms despite at least 2 adequate SRI treatments, and 247 contributed to analysis of the primary outcome measure. Risperidone (up to 4 mg once daily) or placebo. The Clinician-Administered PTSD Scale (CAPS) (range, 0-136). Other measures included the Montgomery-Asberg Depression Rating Scale (MADRS), Hamilton Anxiety Scale (HAMA), Clinical Global Impression scale (CGI), and Veterans RAND 36-Item Health Survey (SF-36V). Change in CAPS scores from baseline to 24 weeks in the risperidone group was -16.3 (95% CI, -19.7 to -12.9) and in the placebo group, -12.5 (95% CI, -15.7 to -9.4); the mean difference was 3.74 (95% CI, -0.86 to 8.35; t = 1.6; P = .11). Mixed model analysis of all time points also showed no significant difference in CAPS score (risperidone: mean, 64.43; 95% CI, 61.98 to 66.89, vs placebo: mean, 67.16; 95% CI, 64.71 to 69.62; mean difference, 2.73; 95% CI, -0.74 to 6.20; P = .12). Risperidone did not reduce symptoms of depression (MADRS mean difference, 1.19; 95% CI, -0.29 to 2.68; P = .11) or anxiety (HAMA mean difference, 1.16; 95% CI, -0.18 to 2.51; P = .09; patient-rated CGI mean difference, 0.20; 95% CI, -0.06 to 0.45; P = .14; observer-rated CGI mean difference, 0.18; 95% CI, 0.01 to 0.34; P = .04), or increase quality of life (SF-36V physical component mean difference, -1.13, 95% CI, -2.58 to 0.32; P = .13; SF-36V mental component mean

  19. Costs and effects of long-acting risperidone compared with oral atypical and conventional depot formulations in Germany.

    Science.gov (United States)

    Laux, Gerd; Heeg, Bart; van Hout, Ben A; Mehnert, Angelika

    2005-01-01

    Schizophrenia is one of the most expensive psychiatric conditions because of high direct and indirect costs associated with the nature of the illness, its resistance to treatment and the consequences of relapse. Long-acting risperidone is a new formulation of an atypical antipsychotic drug that also offers the improvements in compliance associated with haloperidol depot. The aim of this simulation study was to compare the benefits and costs of three pharmacological treatment strategies comprising first-line treatment with long-acting risperidone injection, a haloperidol depot or an oral atypical antipsychotic agent, over a 5-year period in Germany. A discrete event simulation model was developed to compare three treatment scenarios from the perspective of major third-party payers (sickness funds and social security 'Sozialversicherung'). The scenarios comprised first-line treatment with haloperidol depot (scenario 1), long-acting risperidone (scenario 2) and oral olanzapine (scenario 3). Switches to second or third-line options were allowed when side-effects occurred or a patient suffered more than a fixed number of relapses. The model accounted for fixed patient characteristics, and on the basis of these, simulated patient histories according to several time-dependent variables. The time horizon for this model was limited to 5 years, and in accordance with German guidelines, costs and effects were discounted by between 3 and 10%. Direct costs included medication, type of physician visits and treatment location. Indirect costs were not included. Information on treatment alternatives, transition probabilities, model structure and healthcare utilization were derived from the literature and an expert panel. Outcomes were expressed in terms of the number and duration of psychotic episodes, cumulative symptom scores, costs, and quality-adjusted life-years (QALY). Univariate sensitivity analyses were carried out, as were subgroup analyses based on disease severity and

  20. Thermal expansion of an epoxy-glass microsphere composite

    Science.gov (United States)

    Price, H. L.; Burks, H. D.

    1977-01-01

    The thermal expansion of a composite of epoxy (diglycidyl ether of bisphenol A) and solid glass microspheres was investigated. The microspheres had surfaces which were either untreated or treated with a silicone release agent, an epoxy coupling agent, or a general purpose silane coupling agent. Both room temperature (about 300 K) and elevated temperature (about 475 K) cures were used for the epoxy. Two microsphere size ranges were used, about 50 microns, which is applicable in filled moldings, and about 125 microns, which is applicable as bond line spacers. The thermal expansion of the composites was measured from 300 to 350 K or from 300 to 500 K, depending on the epoxy cure temperature. Measurements were made on composites containing up to .6 volume fraction microspheres. Two predictive models, which required only the values of thermal expansion of the polymer and glass and their specific gravities, were tested against the experimental data. A finite element analysis was made of the thermal strain of a composite cell containing a single microsphere surrounded by a finite-thickness interface.

  1. A review on target drug delivery:magnetic microspheres

    Institute of Scientific and Technical Information of China (English)

    Amit Chandna; Deepa Batra; Satinder Kakar; Ramandeep Singh

    2013-01-01

    Novel drug delivery system aims to deliver the drug at a rate directed by the needs of the body during the period of treatment, and target the active entity to the site of action.A number of novel drug delivery systems have emerged encompassing various routes of administration, to achieve controlled and targeted drug delivery, magnetic micro carriers being one of them. Magnetic microsphere is newer approach in pharmaceutical field.Magnetic microspheres as an alternative to traditional radiation methods which use highly penetrating radiation that is absorbed throughout the body.Its use is limited by toxicity and side effects.The aim of the specific targeting is to enhance the efficiency of drug delivery & at the same time to reduce the toxicity & side effects.This kind of delivery system is very much important which localises the drug to the disease site.In this larger amount of freely circulating drug can be replaced by smaller amount of magnetically targeted drug.Magnetic carriers receive magnetic responses to a magnetic field from incorporated materials that are used for magnetic microspheres are chitosan, dextran etc. magnetic microspheres can be prepared from a variety of carrier material. One of the most utilized is serum albumin from human or other appropriate species.Drug release from albumin microspheres can be sustained or controlled by various stabilization procedures generally involving heat or chemical cross-linking of the protein carrier matrix.

  2. A review on target drug delivery: magnetic microspheres

    Directory of Open Access Journals (Sweden)

    Amit Chandna

    2013-01-01

    Magnetic microsphere is newer approach in pharmaceutical field. Magnetic microspheres as an alternative to traditional radiation methods which use highly penetrating radiation that is absorbed throughout the body. Its use is limited by toxicity and side effects. The aim of the specific targeting is to enhance the efficiency of drug delivery & at the same time to reduce the toxicity & side effects. This kind of delivery system is very much important which localises the drug to the disease site. In this larger amount of freely circulating drug can be replaced by smaller amount of magnetically targeted drug. Magnetic carriers receive magnetic responses to a magnetic field from incorporated materials that are used for magnetic microspheres are chitosan, dextran etc. magnetic microspheres can be prepared from a variety of carrier material. One of the most utilized is serum albumin from human or other appropriate species. Drug release from albumin microspheres can be sustained or controlled by various stabilization procedures generally involving heat or chemical cross-linking of the protein carrier matrix.

  3. Study of electrodepositing Au on hollow polystyrene microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Jin Rong [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-987, Mianyang 621900 (China); School of Material Science and Engineering, Xihua University, Chengdu 610039 (China); Zhang Yunwang [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-987, Mianyang 621900 (China); Zhang Lin, E-mail: zhlmy@sina.com [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-987, Mianyang 621900 (China); Wei Chengfu, E-mail: wcf@mail.xhu.edu.cn [School of Material Science and Engineering, Xihua University, Chengdu 610039 (China); Guo Jianjun [School of Material Science and Engineering, Xihua University, Chengdu 610039 (China)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer The gold is electrodeposited on hollow polystyrene microspheres by self-designed setup in this paper. Black-Right-Pointing-Pointer The Au electrodeposit is finer and more uniform on account of the microspheres freely move on the cathode. Black-Right-Pointing-Pointer The morphology, thickness and roughness of Au electrodeposits were analyzed using Scanning Electron Microscopy, X-ray diffraction and Atomic Force Microscope, respectively. - Abstract: The electrodeposited Au film on hollow polystyrene microspheres is successfully prepared by a set of self-designed device. The film is more compact and uniform on account of the microspheres freely moving on the cathode. These experiments mainly focus on the analysis of spherical symmetry, thickness and roughness of electrodeposited Au film. Under conditions of current density 1.5-3 mA cm{sup -2}, the temperature 25 Degree-Sign C, and the stirring rate 150 rpm, the electrodeposited microsphere is coated with a considerably orbicular film. The morphology, thickness and roughness of Au electrodeposits are studied by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and Atomic Force Microscope (AFM), respectively.

  4. Solvent/Non-Solvent Sintering To Make Microsphere Scaffolds

    Science.gov (United States)

    Laurencin, Cato T.; Brown, Justin L.; Nair, Lakshmi

    2011-01-01

    A solvent/non-solvent sintering technique has been devised for joining polymeric microspheres to make porous matrices for use as drug-delivery devices or scaffolds that could be seeded with cells for growing tissues. Unlike traditional sintering at elevated temperature and pressure, this technique is practiced at room temperature and pressure and, therefore, does not cause thermal degradation of any drug, protein, or other biochemical with which the microspheres might be loaded to impart properties desired in a specific application. Also, properties of scaffolds made by this technique are more reproducible than are properties of comparable scaffolds made by traditional sintering. The technique involves the use of two miscible organic liquids: one that is and one that is not a solvent for the affected polymer. The polymeric microspheres are placed in a mold having the size and shape of the desired scaffold, then the solvent/non-solvent mixture is poured into the mold to fill the void volume between the microspheres, then the liquid mixture is allowed to evaporate. Some of the properties of the resulting scaffold can be tailored through choice of the proportions of the liquids and the diameter of the microspheres.

  5. FORMULATION AND EVALUATION OF MUCOADHESIVE MICROSPHERES OF NIFEDIPINE

    Directory of Open Access Journals (Sweden)

    G.V. Radha

    2012-10-01

    Full Text Available In the present study, an attempt has been made to evaluate mucoadhesive microspheres of nifedipine by orifice ionic gelation method employing sodium alginate and different mucoadhesive polymers (HPMC, carbopol alone and in combination of different proportions. The compatibility study was done between drug and polymer by FTIR which shows no interaction between the drug and polymer. The prepared microspheres were evaluated for particle size ,angle of repose, carrs index, swelling index, microencapsulation efficiency, percent drug content, drug release, kinetics and mechanism of drug release. The microspheres were found discrete, spherical, free flowing and the particle size was found in the range of 765 to 792µ. The encapsulation efficiency was found in the range of 55 to 69 %. Percent drug content was found to be in the range of 96 to 99 %. All the microspheres showed good muco adhesive property in the in vitro wash off test. Drug release from the microspheres was found slow, followed first order kinetics with non fickian release mechanism and release dependent on nature and concentration of polymers.

  6. Quantitating error in blood flow measurements with radioactive microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Austin, R.E. Jr.; Hauck, W.W.; Aldea, G.S.; Flynn, A.E.; Coggins, D.L.; Hoffman, J.I.

    1989-07-01

    Accurate determination of the reproducibility of measurements using the microsphere technique is important in assessing differences in blood flow to different organs or regions within organs, as well as changes in perfusion under various experimental conditions. The sources of error of the technique are briefly reviewed. In addition, we derived a method for combining quantifiable sources of error into a single estimate that was evaluated experimentally by simultaneously injecting eight or nine sets of microspheres (each with a different radionuclide label) into four anesthetized dogs. Each nuclide was used to calculate blood flow in 145-190 myocardial regions. We compared each flow determination (using a single nuclide label) with a weighted mean for the piece (based on the remaining nuclides). The difference was defined as ''measured'' error. In all, there were a total of 5,975 flow observations. We compared measured error with theoretical estimates based on the Poisson error of radioactive disintegration and microsphere entrapment, nuclide separation error, and reference flow error. We found that combined estimates based on these sources completely accounted for measured error in the relative distribution of microspheres. In addition, our estimates of the error in measuring absolute flows (which were established using microsphere reference samples) slightly, but significantly, underestimated measured error in absolute flow.

  7. Local blood flow measured by fluorescence excitation of nonradioactive microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Y.; Payne, B.D.; Aldea, G.S.; McWatters, C.; Husseini, W.; Mori, H.; Hoffman, J.I.; Kaufman, L. (Univ. of California, San Francisco (USA))

    1990-05-01

    An X-ray fluorescence system with low Compton background and high counting efficiency was developed to measure regional blood flow with nonradioactive microspheres. The performance of the system was tested in vitro by counting mixed aqueous solutions of either Mo, Ag, and I; Nb, Ag, and Ba; or Zr, Mo, Rh, Ag, Sn, I, and Ba, as well as a mixture of Ag and Ba nonradioactive microspheres. Mixtures containing 2-20 ppm of each element were counted for 10 min by the fluorescence system, and the individual elements in mixtures of three to seven nonradioactive elements were measured with high accuracy. The best counting statistics were obtained for Ag. For 10-min counts, the system measures as few as 120 Ag microspheres with 30% standard deviation but measures 800 Ag microspheres per sample with 3.6% standard deviation. We compared regional myocardial blood flows determined simultaneously by fluorescence and radioactive microsphere methods; the latter samples were counted by a 3-in. NaI (Tl) well detector and pulse-height analyzer. The radioactive and nonradioactive measurements showed good correlations.

  8. Long-term stability, biocompatibility and oral delivery potential of risperidone-loaded solid lipid nanoparticles.

    Science.gov (United States)

    Silva, A C; Kumar, A; Wild, W; Ferreira, D; Santos, D; Forbes, B

    2012-10-15

    A solid lipid nanoparticles (SLN) formulation to improve the oral delivery of risperidone (RISP), a poorly water-soluble drug, was designed and tested. Initially, lipid-RISP solubility was screened to select the best lipid for SLN preparation. Compritol(®)-based formulations were chosen and their long-term stability was assessed over two years of storage (at 25 °C and 4 °C) by means of particle size, polydispersity index (PI), zeta potential (ZP) and encapsulation efficiency (EE) measurements. SLN shape was observed by transmission electron microscopy (TEM) at the beginning and end of the study. The oxidative potential (OP) of the SLN was measured and their biocompatibility with Caco-2 cells was evaluated using the (4,5-dimethylthiazol-2-yl)2,5-dyphenyl-tetrazolium bromide (MTT) assay. In vitro drug release and transport studies were performed to predict the in vivo release profile and to evaluate the drug delivery potential of the SLN formulations, respectively. The RISP-loaded SLN systems were stable and had high EE and similar shape to the placebo formulations before and after storage. Classical Fickian diffusion was identified as the release mechanism for RISP from the SLN formulation. Biocompatibility and dose-dependent RISP transport across Caco-2 cells were observed for the prepared SLN formulations. The viability of SLN as formulations for oral delivery of poorly water-soluble drugs such as RISP was illustrated.

  9. Excessive weight gain after remission of depression in a schizophrenic patient treated with risperidone: case report

    Directory of Open Access Journals (Sweden)

    Psarros Constantin

    2006-09-01

    Full Text Available Abstract Background The use of atypical antipsychotics in schizophrenic patients has been associated with a risk of weight gain. Similarly, recovery from depression is often followed by improved appetite, greater food intake and potential increase in weight. Case presentation A Caucasian 33-year-old schizophrenic female patient was being treated with 6 mg/day of risperidone and 15 mg/day of clorazepate. She developed depressive symptomatology and 40 mg/day of fluoxetine was gradually added to her treatment regimen for about 9 months. After the remission of depression, and the discontinuation of fluoxetine, she experienced an increase in appetite and subsequently excessive weight gain of 52 kg. Re-administration of fluoxetine did not reverse the situation. The patient developed diabetes mellitus, which was successfully controlled with metformin 1700 mg/day. The addition at first of orlistat 360 mg/day and later of topiramate 200 mg/day has helped her to lose a significant part of the weight gained (30 kg. Conclusion The case suggests a probable association between the remission of depressive symptomatology and weight gain in a schizophrenic patient.

  10. Emerging treatments in the management of bipolar disorder – focus on risperidone long acting injection

    Directory of Open Access Journals (Sweden)

    Wissam El-Hage

    2010-07-01

    Full Text Available Wissam El-Hage1, Simon A Surguladze21Inserm U930 ERL CNRS 3106, Université François Rabelais and Clinique Psychiatrique Universitaire, CHRU de Tours, Tours, France; 2Institute of Psychiatry, King’s College London, UKAbstract: Bipolar disorder is a life-long psychiatric illness characterized by a high frequency of relapses and substantial societal costs. Almost half of the patients are prescribed second generation antipsychotics for treatment of manic states, or as the maintenance therapy. ­Risperidone long acting injection (RLAI as a monotherapy or as adjunctive therapy to lithium or valproate for the maintenance treatment of bipolar I disorder was approved by Food and Drug Administration (FDA in United States in May 2009. In this review we will consider the aspects of pharmacology, pharmacokinetics, metabolism, safety and tolerability, and clinical trials focusing on the efficacy of RLAI in bipolar disorder. The patients’ perspective and attitudes to long-acting injections will also be discussed.Keywords: second generation, antipsychotics, patient attitudes, lithium, valproate, monotherapy

  11. Effect of blonanserin on cognitive and social function in acute phase Japanese schizophrenia compared with risperidone.

    Science.gov (United States)

    Hori, Hikaru; Yamada, Kenji; Kamada, Dan; Shibata, Yuka; Katsuki, Asuka; Yoshimura, Reiji; Nakamura, Jun

    2014-01-01

    This study aims to determine the effectiveness of blonanserin (BNS) on the cognitive and social functions of patients with schizophrenia compared with risperidone (RIS) during acute-phase (8-week) treatment. A total of 39 schizophrenia inpatients were included in this study. The subjects received either BNS (N=20) or RIS (N=19), and the clinical responses were evaluated periodically. The concomitant use of mood stabilizers was not allowed. Efficacy was assessed with the Positive and Negative Syndrome Scale for schizophrenia. Cognition was assessed using the Brief Assessment of Cognition in Schizophrenia, Japanese-language version. Social function was assessed using the Life Assessment Scale for the Mentally Ill. For both groups, each assessment exhibited a decrease in the mean change from baseline on the Positive and Negative Syndrome Scale. The depression subscale was significantly improved in the BNS group compared with the RIS group at 8 weeks after administration. BNS improved verbal fluency and executive function (cognitive function) and daily living and work skills (social function). Compared with the RIS group, BNS was observed to improve daily living. BNS may improve psychotic symptoms, cognitive function, and daily living in patients with acute-phase schizophrenia. BNS may be superior to RIS in the improvement of daily living.

  12. Temperature influence in crystallinity of polymer microspheres; Influencia da temperatura na cristalinidade de microesferas polimericas

    Energy Technology Data Exchange (ETDEWEB)

    Rezende, Cristiane de P.; Novack, Katia M., E-mail: knovack@iceb.ufop.br [Universidade Federal de Ouro Preto - UFOP, ICEB, DEQUI, Ouro Preto, MG (Brazil)

    2011-07-01

    Drug delivery technology is evolving through the creation of new techniques of drug delivery effectively. The new methods used in drugs administration are based in microencapsulation process. Microsphere encapsulation modifies drug delivery bringing benefits and efficiency. In this work has been evaluated the influence of temperature in microspheres preparation. Microspheres were obtained by PMMA-co-PEG (COP) copolymer with indomethacin inserted in polymer matrix. Samples were characterized by SEM, DSC and XRD. SEM micrographs confirmed the formation of different sizes of microspheres and it was verified that higher temperatures make more crystalline microspheres. (author)

  13. Super-resolution optical microscopy based on scannable cantilever-combined microsphere.

    Science.gov (United States)

    Wang, Shuying; Zhang, Dongxian; Zhang, Haijun; Han, Xu; Xu, Rui

    2015-12-01

    We report an ingenious method of super-resolution optical microscopy utilizing scannable cantilever-combined microsphere. By scanning the microsphere over the sample surface in a cantilever-combined microsphere-sample contact state, super-resolution images can be acquired at arbitrary sample regions through near-field information collection by the microsphere. In addition, such a state can effectively reduce the possibility of breaking the cantilever and damaging the microsphere or sample surface. This work has developed a new method and technique of sub-diffraction-limit optical microscopy, and can be practically applied in various fields of micro/nanoscopy.

  14. Nano pores evolution in hydroxyapatite microsphere during spark plasma sintering

    Directory of Open Access Journals (Sweden)

    Lin C.

    2011-01-01

    Full Text Available Micron-spherical granules of hydroxyapatite (HAp nanoparticles were prepared by powder granulation methods. Through subsequent sintering, porous HAp microspheres with tailored pore and grain framework structures were obtained. Detailed microstructure investigation by SEM and TEM revealed the correlation of the pore structure and the necking strength with the sintering profiles that determine the coalescence features of the nanoparticles. The partially sintered porous HAp microspheres containing more than 50% porosity consisting of pores and grains both in nano-scale are active in inducing the precipitation of HAp in simulated body fluid. The nano-porous HAp microspheres with an extensive surface and interconnecting pores thus demonstrate the potential of stimulating the formation of collagen and bone and the integration with the newly formed bones during physiological bone remodeling.

  15. QUANTUM LANGEVIN THEORY OF WHISPERING-GALLERY-MODE MICROSPHERE LASER

    Institute of Scientific and Technical Information of China (English)

    CHAI JIN-HUA; LU YI-QUN; LEUNG PUI-TANG

    2000-01-01

    A quantum Langevin theory of whispering-gallery-mode microsphere laser theory is developed. The linear and nonlinear analysis are made for laser operation below and above the threshold. In these analysis, corresponding to the specific property of microsphere, the effect of inversion fluctuation is treated. The coherence functions of laser field are calculated, and the intensity, the amplitude fluctuation and the linewidth of the field are obtained, which are connected with the enhancement factor of whispering-gallery-mode microsphere. It is shown that the strong couple and strong pumping are useful for the amplification of intensity and the decrease of linewidth below the threshold. It is also shown that, for the laser action above threshold, the variances of photon number and the linewidth of internal field are related to the enhancement factor and the square of the enhancement factor, respectively.

  16. Multifrequency transverse Faraday effect in single magneto-dielectric microspheres

    CERN Document Server

    Maksymov, Ivan S

    2014-01-01

    We propose using a single magneto-dielectric microsphere as a device for enhancing the transverse Faraday effect at multiple wavelengths at the same time. Although the diameter of the sphere can be $<1$ $\\mu$m, the numerically predicted strength of its magneto-optical (MO) response can be an order of magnitude stronger than in MO devices based on thick magnetic plates. The MO response of a microsphere is also comparable with that of subwavelength magneto-dielectric gratings which, however, operate at a single wavelength and occupy a large area. In contrast to gratings and thick plates, the compact size of the microsphere and its capability to support spin-wave excitations make it suitable for applications in nanophotonics, imaging systems, and magnonics.

  17. Coacervate-like microspheres from lysine-rich proteinoid

    Science.gov (United States)

    Rohlfing, D. L.

    1975-01-01

    Microspheres form isothermally from lysine-rich proteinoid when the ionic strength of the solution is increased with NaCl or other salts. Studies with different monovalent anions and with polymers of different amino acid composition indicate that charge neutralization and hydrophobic bonding contribute to microsphere formation. The particles also form in sea water, especially if heated or made slightly alkaline. The microspheres differ from those made from acidic proteinoid but resemble coacervate droplets in some ways (isothermal formation, limited stability, stabilization by quinone, uptake of dyes). Because the constituent lysine-rich proteinoid is of simulated prebiotic origin, the study is interpreted to add emphasis to and suggest an evolutionary continuity for coacervation phenomena.

  18. Monocrotophos Molecularly Imprinted Microspheres Prepared by Precipitation Polymerization in Acetonitrile

    Institute of Scientific and Technical Information of China (English)

    Shoulei Yan; Zhixian Gao; Yanjun Fang; Yiyong Cheng

    2006-01-01

    Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (CAN) 60℃, 24 h, using methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA) and 2,2-azobisiobutyronitrile (AIBN) as functional monomer, cross-linker and initiator, respectively. The recognition mechanism was elucidated by UV-vis spectra and computer modeling. Equilibrium binding experiment was employed to investigate the rebinding properties, Scatchard analysis showed that specific binding sites formed in the imprinted microspheres, and there were two kinds of binding sites, one was high binding sites, the other was low binding sites. This microspheres can be useful affinity absorbent used for organophosphorus pesticides separation and purification in food and environmental analysis.

  19. Protein microspheres as suitable devices for piroxicam release.

    Science.gov (United States)

    Silva, Raquel; Ferreira, Helena; Carvalho, Ana C; Gomes, Andreia C; Cavaco-Paulo, Artur

    2012-04-01

    Bovine serum albumin-piroxicam (BSA-piroxicam) and human serum albumin-piroxicam (HSA-piroxicam) microspheres were sonochemically prepared and characterized. The use of polyvinyl alcohol (PVA) lead to an improvement of formulation characteristics, including smaller size, lower polydispersity index (PDl), higher entrapment efficiency and higher stability. The release kinetics of these proteinaceous microspheres was determined in presence of protease, indicating an anomalous drug transport mechanism (diffusion and polymer degradation). In presence of higher protease concentration, BSA microspheres exhibit Case II transport, leading to zero order release (protein degradation). These proteinaceous devices did not show cytotoxicity against human skin fibroblasts in vitro, for range concentrations below to 300 mg L(-1), greatly supporting their potential application in the treatment of inflammatory diseases.

  20. Chitosan bio-based organic-inorganic hybrid aerogel microspheres.

    Science.gov (United States)

    El Kadib, Abdelkrim; Bousmina, Mosto

    2012-07-02

    Recently, organic-inorganic hybrid materials have attracted tremendous attention thanks to their outstanding properties, their efficiency, versatility and their promising applications in a broad range of areas at the interface of chemistry and biology. This article deals with a new family of surface-reactive organic-inorganic hybrid materials built from chitosan microspheres. The gelation of chitosan (a renewable amino carbohydrate obtained by deacetylation of chitin) by pH inversion affords highly dispersed fibrillar networks shaped as self-standing microspheres. Nanocasting of sol-gel processable monomeric alkoxides inside these natural hydrocolloids and their subsequent CO(2) supercritical drying provide high-surface-area organic-inorganic hybrid materials. Examples including chitosan-SiO(2), chitosan-TiO(2), chitosan-redox-clusters and chitosan-clay-aerogel microspheres are described and discussed on the basis of their textural and structural properties, thermal and chemical stability and their performance in catalysis and adsorption.

  1. Development of activity standard for {sup 90}Y microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Mo, L. [Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234 (Australia) and Institute of Medical Physics, University of Sydney, NSW 2006 (Australia)]. E-mail: lmx@ansto.gov.au; Avci, B. [SIRTeX Medical Limited, Unit F6 Parkview, 16 Mars Road, Lane Cove, NSW 2066 (Australia); James, D. [SIRTeX Medical Limited, Unit F6 Parkview, 16 Mars Road, Lane Cove, NSW 2066 (Australia); Simpson, B. [CSIR National Metrology Laboratory, 15 Lower Hope Road, Rosebank, Cape Town 7700 (South Africa); Van Wyngaardt, W.M. [CSIR National Metrology Laboratory, 15 Lower Hope Road, Rosebank, Cape Town 7700 (South Africa); Cessna, J.T. [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Baldock, C. [Institute of Medical Physics, University of Sydney, NSW 2006 (Australia)

    2005-08-01

    {sup 90}Y microspheres are important therapeutic radiopharmaceuticals used in the treatment of liver cancer through a process known as selective internal radiation therapy. SIR-spheres[reg] is a radiopharmaceutical product that is comprised of {sup 90}Y microspheres suspended in sterile, pyrogen-free water for injection into patients. It is necessary to establish for the SIR-spheres[reg] production the capability of accurately measuring the activity of this product to a traceable national measurement standard. An activity standard for SIR-spheres[reg] was developed from a standard for {sup 90}Y solution, employing a highly quantifiable chemical digestion process. Calibration factors for the manufacturer's ionisation chambers were determined for 1 and 5 ml of the SIR-spheres[reg] product placed in Wheaton vials, for both 34% and 44% of {sup 90}Y microsphere concentration.

  2. Worsening of myasthenia gravis after administration of injectable long-acting risperidone for treatment of schizophrenia; first case report and a call for caution.

    Science.gov (United States)

    Al-Hashel, Jasem Y; Ismail, Ismail Ibrahim; John, John K; Ibrahim, Mohammed; Ali, Mahmoud

    2016-01-01

    Myasthenia gravis is an autoimmune disease characterized by muscle weakness due to autoantibodies affecting the neuromuscular junction. Co-occurrence of myasthenia gravis and schizophrenia is very rare and raises a challenge in management of both diseases. Antipsychotic drugs exhibit anticholinergic side effects and have the potentials of worsening myasthenia. Long-acting risperidone is an injectable atypical antipsychotic drug that has not been previously reported to worsen myasthenia gravis in literature. We report the first case report of worsening of myasthenia after receiving long-acting risperidone injection for schizophrenia in a 29-year-old female with both diseases. She started to have worsening 2 weeks following the first injection and her symptoms persisted despite receiving plasma exchange. This could be explained by the pharmacokinetics of the drug. We recommend that long-acting risperidone should be used with caution in patients with myasthenia gravis, and clinicians must be aware of the potential risks of this therapy.

  3. Synthesis, recognition and evaluation of molecularly imprinted polymer nanoparticle using miniemulsion polymerization for controlled release and analysis of risperidone in human plasma samples

    Energy Technology Data Exchange (ETDEWEB)

    Asadi, Ebadullah; Azodi-Deilami, Saman; Abdouss, Majid [Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Kordestani, Davood [Razi University, Kermanshah (Iran, Islamic Republic of); Rahimi, Alireza [Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of); Asadi, Somayeh [Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of)

    2014-06-15

    We prepared high selective imprinted nanoparticle polymers by a miniemulsion polymerization technique, using risperidone as the template, MAA as the functional monomers, and TRIM as the cross-linker in acetonitrile as solvent. The morphology of the nanoparticles determined by scanning electron microscopy (SEM) images and drug release, binding properties and dynamic light scattering (DLS) of molecularly imprinted polymers (MIPs) were studied. Controlled release of risperidone from nanoparticles was investigated through in 1% wt sodium dodecyl sulfate aqueous solution and by measuring the absorbance by HPLC-UV. The results showed that the imprinted nanoparticles exhibited a higher binding level and slower release rate than non-imprinted nanoparticles, which contributed to interaction of risperidone with imprinted cavities within nanoparticles. Furthermore, the results from HPLC showed good precision (5% for 50.0 µg L{sup -1}) and recoveries (between 86-91) using MIP from human plasma samples.

  4. Polysaccharide-based aerogel microspheres for oral drug delivery.

    Science.gov (United States)

    García-González, C A; Jin, M; Gerth, J; Alvarez-Lorenzo, C; Smirnova, I

    2015-03-06

    Polysaccharide-based aerogels in the form of microspheres were investigated as carriers of poorly water soluble drugs for oral administration. These bio-based carriers may combine the biocompatibility of polysaccharides and the enhanced drug loading capacity of dry aerogels. Aerogel microspheres from starch, pectin and alginate were loaded with ketoprofen (anti-inflammatory drug) and benzoic acid (used in the management of urea cycle disorders) via supercritical CO2-assisted adsorption. Amount of drug loaded depended on the aerogel matrix structure and composition and reached values up to 1.0×10(-3) and 1.7×10(-3) g/m(2) for ketoprofen and benzoic acid in starch microspheres. After impregnation, drugs were in the amorphous state in the aerogel microspheres. Release behavior was evaluated in different pH media (pH 1.2 and 6.8). Controlled drug release from pectin and alginate aerogel microspheres fitted Gallagher-Corrigan release model (R(2)>0.99 in both cases), with different relative contribution of erosion and diffusion mechanisms depending on the matrix composition. Release from starch aerogel microspheres was driven by dissolution, fitting the first-order kinetics due to the rigid starch aerogel structure, and showed different release rate constant (k1) depending on the drug (0.075 and 0.160 min(-1) for ketoprofen and benzoic acid, respectively). Overall, the results point out the possibilities of tuning drug loading and release by carefully choosing the polysaccharide used to prepare the aerogels.

  5. The mechanism of protein release from triglyceride microspheres.

    Science.gov (United States)

    Zaky, A; Elbakry, A; Ehmer, A; Breunig, M; Goepferich, A

    2010-10-15

    The purpose of this study was to reveal factors that have an impact on the protein release kinetics from triglyceride microspheres prepared by spray congealing. We investigated the effect of protein particle size, morphology and distribution on protein release from microspheres by confocal laser scanning microscopy (CLSM)(.) The microspheres were loaded with three types of model particles made of FITC-labeled bovine serum albumin: freeze dried protein, spherical particles obtained by precipitation in the presence of PEG and micronized material. Investigation by light microscopy and laser light diffraction revealed that the freeze dried material consisted mainly of app. 29 μm elongated shaped particles. The precipitated BSA consisted mainly of 9.0 μm diameter spherically shaped particles while the micronized protein prepared by jet milling consisted of 4.9 μm sized rounded particles of high uniformity. Microspheres were embedded into a cold-curing resin and cut with a microtome. Subsequent investigation by CLSM revealed major differences of distribution of the polydisperse protein particles inside the microsphere sections depending on the type of BSA that was used. Particles of micronized and precipitated protein were distributed almost throughout the microsphere cross section. The protein distribution had a marked impact on the release kinetics in phosphate buffer. Large protein particles led to a considerably faster release than small ones. By staining the release medium we demonstrated that in all three cases there was a strong correlation between protein release and buffer intrusion. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Preparation of monodisperse, superparamagnetic, luminescent, and multifunctional PGMA microspheres with amino-groups

    Institute of Scientific and Technical Information of China (English)

    WANG WeiCai; ZHANG Qi; ZHANG BingBo; LI DeNa; DONG XiaoQing; ZHANG Lei; CHANG Jin

    2008-01-01

    Micron-sized, monodisperse, superparamagnetic, luminescent composite poly(glycidyl methacrylate) (PGMA) microspheres with functional amino-groups were successfully synthesized in this study. The process of preparation was as follows: preparation of monodisperse poly(glycidyl methacrylate) mi-crospheres by dispersion polymerization method; modification of poly(glycidyl methacrylate) micro-spheres with ethylene diamine to form amino-groups; impregnation of iron ions (Fe2+ and Fe3+) inside the microspheres and subsequently precipitating them with ammonium hydroxide to form magnetite (Fe3O,4>) nanoparticles within the polymer microspheres; infusion of CdSe/CdS core-shell quantum dots (QDs) into magnetic polymer microspheres. Scanning electron microscopy (SEM) was used to char-acterize surface morphology and size distribution of composite microspheres. The average size of mi-crospheres was 1.42μm with a size variation of 3.8%, The composite microspheres were bright enough and easily observed using a conventional fluorescence microscope, The composite microspheres were easily separated from solution by magnetic decantation using a permanent magnet. The new multi-functional composite microspheres are promising to be used in a variety of bioanalytical assays in-volving luminescence detection and magnetic separation.

  7. Preparation of poly (L-lactic acid) microspheres by droplet-freezing process

    Energy Technology Data Exchange (ETDEWEB)

    Mao Yi [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Jiangsu Key Laboratory of Advanced Metallic Materials, Nanjing 211189 (China); Dong Yinsheng, E-mail: dongys@seu.edu.cn [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Jiangsu Key Laboratory of Advanced Metallic Materials, Nanjing 211189 (China); Lin Pinghua [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Huazhong University of Science and Technology, Wuhan 430074 (China); Chu Chenglin; Sheng Xiaobo; Guo Chao [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Jiangsu Key Laboratory of Advanced Metallic Materials, Nanjing 211189 (China)

    2011-01-01

    A recently developed process of microsphere preparation, named droplet-freezing process is introduced in this paper. The PLLA microspheres were fabricated by the droplet-freezing process, the diameter and porosity of the microspheres were measured, and the micro-morphologies of the microspheres were characterized by scanning electron microscopy (SEM). The formation process of microspheres was achieved by two steps: first, after droplets dropped off the delivery tube, they became approximately spherical in the air under the effect of the surface tension; second, droplets dropped into liquid condensate and maintained the spherical shape, and were frozen during the free settling process. Experimental results indicated that the microspheres fabricated by the droplet-freezing process have uniform diameters and the diameter can be controlled properly, along with the increase of the PLLA concentration, the size of microspheres increases, but the porosity of the microspheres decreases. The microspheres with high porosity can be obtained with a low concentration of the PLLA solution. SEM analysis revealed that the surfaces and interiors of the microsphere contain plentiful and interconnected micro pores. The microspheres are hopeful to be applied in bone tissue engineering.

  8. Preparation and surface modification of magnetic poly(methyl methacrylate) microspheres

    Institute of Scientific and Technical Information of China (English)

    YANG Chengli; GUAN Yueping; XING Jianmin; LIU Junguo; AN Zhentao; LIU Huizhou

    2004-01-01

    A novel method for preparation of magnetic polymer microspheres by spraying suspension polymerization (SSP) was developed. Relatively uniform magnetic poly(methyl methacrylate) microspheres were prepared by the spraying suspension polymerization (SSP)using methyl methacrylate (MMA) as monomer, divinylbenzene (DVB) as cross-linking agent,benzoyl peroxide (BPO) as initiator and polyvinyl alcohol (PVA) as stabilizer in the presence of hydrophobic Fe3O4 magnetic fluid. The microspheres prepared were modified by surface chemical reaction. The magnetic properties and morphology of the microspheres were examined by SEM and VSM respectively. The active functional groups of microspheres were examined by infrared spectra. The results showed that microspheres with saturation magnetization of 16.8emu/g showed distinct superparamagnetic characteristics and the magnetic microspheres with a size of 10 μm were relatively uniform.

  9. Preparation,Characterization,and in vitro Release of Biodegradable Erythromycin-gelatin Microspheres

    Institute of Scientific and Technical Information of China (English)

    WANG Fei; LIU Pai; JIANG Dan; LIU Cheng-bai; ZHANG Feng-chun; CHEN Xia

    2008-01-01

    Blank and erythromycin-loaded gelatin microspheres were successfully fabricated via emulsion chemical crosslinking technique.The surface morphology of the microspheres was characterized by scanning electron microscope(SEM)and optical microscope.The results show that the microspheres wcre spherical and smooth.The particle average size of erythromycin-loaded microspheres Was found to be 20.6 μm,with a high purity of more than 90%and with a good dispersibility.The microspheres could be obtained in a high yield.Erythromycin released from the microspheres Was monitored in buffer and artificial body fluid at 37℃.Average drug content was 27.2%, and erythromycin-loaded gelatin microspheres showed good release profiles with a nearly constant release during 4-8h in artificial body fluid in vitro degradation studies.These gelatin mierospheres are useful for studying and developing various drug-delivery systems.

  10. Preparation and structure of drug-carrying biodegradable microspheres designed for transarterial chemoembolization therapy.

    Science.gov (United States)

    Wang, Yujing; Benzina, Abderazak; Molin, Daniel G M; Akker, Nynke van den; Gagliardi, Mick; Koole, Leo H

    2015-01-01

    Biodegradable poly(D,L-lactic acid) drug-eluting microspheres containing anti-tumor drugs, cisplatin, and sorafenib tosylate have been prepared by the emulsion solvent evaporation method with diameter between 200 and 400 μm. Scanning electron microscopy showed that cisplatin microspheres had smooth surfaces, while sorafenib tosylate microspheres and cisplatin + sorafenib tosylate microspheres were porous at the surface and the pits of the latter were larger than those of the former. Notably, cisplatin + sorafenib tosylate microspheres had a fast drug release rate compared with microspheres containing one drug alone. In vitro cytotoxicity experiments and classical matrigel endothelial tube assay certificated the maintaining bioactivity of cisplatin and sorafenib tosylate released from the microspheres, respectively. This work provides a useful approach for the fabrication of drug-eluting beads used in transarterial chemoembolization.

  11. Modified composite microspheres of hydroxyapatite and poly(lactide-co-glycolide) as an injectable scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xixue [BNLMS, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology, Beijing 100190 (China); Shen, Hong, E-mail: shenhong516@iccas.ac.cn [BNLMS, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Yang, Fei [BNLMS, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Liang, Xinjie [CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology, Beijing 100190 (China); Wang, Shenguo, E-mail: wangsg@iccas.ac.cn [BNLMS, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Wu, Decheng, E-mail: dcwu@iccas.ac.cn [BNLMS, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-02-15

    The compound of hydroxyapatite-poly(lactide-co-glycolide) (HA-PLGA) was prepared by ionic bond between HA and PLGA. HA-PLGA was more stable than the simple physical blend of hydroxyapatite and poly(lactide-co-glycolide) (HA/PLGA). The surface of HA-PLGA microsphere fabricated by an emulsion–solvent evaporation method was rougher than that of HA/PLGA microspheres. Moreover, surface HA content of HA-PLGA microspheres was more than that of HA/PLGA microspheres. In vitro mouse OCT-1 osteoblast-like cell culture results showed that the HA-PLGA microspheres clearly promoted osteoblast attachment, proliferation and alkaline phosphatase activity. It was considered that surface rich HA component and rough surface of HA-PLGA microsphere enhanced cell growth and differentiation. The good cell affinity of the HA-PLGA microspheres indicated that they could be used as an injectable scaffold for bone tissue engineering.

  12. Biomass Vanillin-Derived Polymeric Microspheres Containing Functional Aldehyde Groups: Preparation, Characterization, and Application as Adsorbent.

    Science.gov (United States)

    Zhang, Huanyu; Yong, Xueyong; Zhou, Jinyong; Deng, Jianping; Wu, Youping

    2016-02-03

    The contribution reports the first polymeric microspheres derived from a biomass, vanillin. It reacted with methacryloyl chloride, providing monomer vanillin methacrylate (VMA), which underwent suspension polymerization in aqueous media and yielded microspheres in high yield (>90 wt %). By controlling the N2 bubbling mode and by optimizing the cosolvent for dissolving the solid monomer, the microspheres were endowed with surface pores, demonstrated by SEM images and mercury intrusion porosimetry measurement. Taking advantage of the reactive aldehyde groups, the microspheres further reacted with glycine, thereby leading to a novel type of Schiff-base chelating material. The functionalized microspheres demonstrated remarkable adsorption toward Cu(2+) (maximum, 135 mg/g) which was taken as representative for metal ions. The present study provides an unprecedented class of biobased polymeric microspheres showing large potentials as adsorbents in wastewater treatment. Also importantly, the reactive aldehyde groups may enable the microspheres to be used as novel materials for immobilizing biomacromolecules, e.g. enzymes.

  13. Controlled Synthesis of Hierarchically Assembled Porous ZnO Microspheres with Enhanced Gas-Sensing Properties

    Directory of Open Access Journals (Sweden)

    Shengsheng You

    2015-01-01

    Full Text Available The ZnO microspheres constructed by porous nanosheets were successfully synthesized by calcinating zinc hydroxide carbonate (ZHC microspheres obtained by a sample hydrothermal method. The samples were characterized in detail with scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffraction (XRD, and thermogravimetric and differential scanning calorimetry (TG-DSC. The results indicated that the prepared ZnO microspheres were well crystalline with wurtzite hexagonal phase. The effects of reaction time, temperature, the amount of trisodium citrate, and urea on the morphology of ZnO microspheres were studied. The formation mechanism of porous ZnO microspheres was discussed. Furthermore, the gas-sensing properties for detection of organic gas of the prepared porous ZnO microspheres were investigated. The results indicated that the prepared porous ZnO microspheres exhibited high gas-sensing properties for detection of ethanol gas.

  14. Preparation of PVA/amino multi-walled carbon nanotubes nanocomposite microspheres for endotoxin adsorption.

    Science.gov (United States)

    Zong, Wenhui; Chen, Jian; Han, Wenyan; Cheng, Guanghui; Chen, Jie; Wang, Yue; Wang, Weichao; Ou, Lailiang; Yu, Yaoting; Shen, Jie

    2017-03-23

    A novel polyvinyl alcohol-amino multi-walled carbon nanotube (PVA-AMWCNT) nanocomposite microsphere was prepared successfully for the first time and used for endotoxin removal. The resulting AMWCNT modified PVA microsphere was characterized by SEM, Raman spectrum and fluorescence image, which indicated AMWCNT was dispersed into the macropores of PVA microsphere uniformly. The PVA-AMWCNT microspheres showed better adsorption capability and faster adsorption equilibrium for endotoxin in aqueous solution when compared to the PVA microsphere with polymyxin B (PMB) as ligand. More noteworthy, the PVA based microspheres had little nonspecific adsorption in simulated serum. Therefore, PVA-AMWCNT nanocomposite microsphere with an excellent haemocompatibility has a great potential application in clinical blood purification.

  15. Search for Millicharged Particles Using Optically Levitated Microspheres

    CERN Document Server

    Moore, David C; Gratta, Giorgio

    2014-01-01

    We report results from a search for stable particles with charge > $10^{-5}$ e in bulk matter using levitated dielectric microspheres in high vacuum. No evidence for such particles was found in a total sample of 1.4 ng, providing an upper limit on the abundance per nucleon of 2.5 x $10^{-14}$ at the 95% confidence level for the material tested. These results provide the first direct search for single particles with charge < 0.1 e bound in macroscopic quantities of matter and demonstrate the ability to perform sensitive force measurements using optically levitated microspheres in vacuum.

  16. Optical diffraction by ordered 2D arrays of silica microspheres

    Science.gov (United States)

    Shcherbakov, A. A.; Shavdina, O.; Tishchenko, A. V.; Veillas, C.; Verrier, I.; Dellea, O.; Jourlin, Y.

    2017-03-01

    The article presents experimental and theoretical studies of angular dependent diffraction properties of 2D monolayer arrays of silica microspheres. High-quality large area defect-free monolayers of 1 μm diameter silica microspheres were deposited by the Langmuir-Blodgett technique under an accurate optical control. Measured angular dependencies of zeroth and one of the first order diffraction efficiencies produced by deposited samples were simulated by the rigorous Generalized Source Method taking into account particle size dispersion and lattice nonideality.

  17. Investigation of Expandable Polymeric Microspheres for Packaging Applications

    Science.gov (United States)

    2012-06-06

    REDUCTION RATIONS LIGHTWEIGHT BIODEGRADATION MILITARY RATIONS PACKING MATERIALS SAVINGS POLYOLEFINS WASTE...microspheres is the MRETM menu  bag .      The  investigation  of  polymeric  microspheres  for  food  packaging  applications  will  continue as a CFREP...in military food packaging applications, specifically the FRH pouch and the MRETM menu  bag .     Based on the three trials, the blown multilayer film

  18. Alginate-Casein Microspheres as Bioactive Vehicles for Nutrients

    Institute of Scientific and Technical Information of China (English)

    何志敏; 张茜青; 齐崴; 黄仁亮; 苏荣欣

    2015-01-01

    The aim of this work was to develop an alginate-casein composite microsphere as a bioactive vehicle for oral administration of nutrients by a simple extrusion dripping method. Riboflavin was selected as a model drug, and the microencapsulation efficiency was raised to 97.94%after optimizing the preparation conditions by response surface methodology. In vitro release studies showed that riboflavin was released completely from alginate-casein microspheres in simulated intestinal fluids. Meanwhile, the morphology, structure and interaction between alginate and casein were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectra.

  19. A comparison of low-dose risperidone to paroxetine in the treatment of panic attacks: a randomized, single-blind study

    Directory of Open Access Journals (Sweden)

    Galynker Igor I

    2009-05-01

    Full Text Available Abstract Background Because a large proportion of patients with panic attacks receiving approved pharmacotherapy do not respond or respond poorly to medication, it is important to identify additional therapeutic strategies for the management of panic symptoms. This article describes a randomized, rater-blind study comparing low-dose risperidone to standard-of-care paroxetine for the treatment of panic attacks. Methods Fifty six subjects with a history of panic attacks were randomized to receive either risperidone or paroxetine. The subjects were then followed for eight weeks. Outcome measures included the Panic Disorder Severity Scale (PDSS, the Hamilton Anxiety Scale (Ham-A, the Hamilton Depression Rating Scale (Ham-D, the Sheehan Panic Anxiety Scale-Patient (SPAS-P, and the Clinical Global Impression scale (CGI. Results All subjects demonstrated a reduction in both the frequency and severity of panic attacks regardless of treatment received. Statistically significant improvements in rating scale scores for both groups were identified for the PDSS, the Ham-A, the Ham-D, and the CGI. There was no difference between treatment groups in the improvement in scores on the measures PDSS, Ham-A, Ham-D, and CGI. Post hoc tests suggest that subjects receiving risperidone may have a quicker clinical response than subjects receiving paroxetine. Conclusion We can identify no difference in the efficacy of paroxetine and low-dose risperidone in the treatment of panic attacks. Low-dose risperidone appears to be tolerated equally well as paroxetine. Low-dose risperidone may be an effective treatment for anxiety disorders in which panic attacks are a significant component. Trial Registration ClinicalTrials.gov Identifier: NCT100457106

  20. Dopamine transporter density assessed with [{sup 123}]IPT SPECT before and after risperidone treatment in children with tourette's disorder

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Young Hoon; Kim, Tae Hoon; Ryu, Won Gee [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of)] [and others

    2004-02-01

    Tourette's disorder (TD), which is characterized by multiple waxing and waning motor tics and one or more vocal tics, is known to be associated with abnormalities in the dopaminergic system. To testify our hypothesis that risperidone would improve tic symptoms of TD patients through the change of the dopaminergic system, we measured the dopamine transporter (DAT) densities between drug-naive children with TD and normal children, and investigated the DAT density before and after treatment with risperidone in drug-naive children with TD, using iodine-123 labelled N-(3-iodopropen-2-yl)-2{beta}-carbomethoxy-3beta-(4-chlorophenyl)tropane ([{sup 123}I]IPT) single photon emission computed tomography (SPECT). [{sup 123I}]IPT SPECT imaging and Yale Global Tic Severity Scale-Korean version (YGTSS-K) for assessing the tic symptom severity were carried out before and after treatment with risperidone for 8 weeks in nine drug-naive children with TD. Eleven normal children also underwent SPECT imaging 2 hours after an intravenous administration of [{sup 123}I]IPT. Drug-naive children with TD had a significantly greater increase in the specific/nonspecific DAT binding ratio of both basal ganglia compared with the normal children. However, no significant difference in the specific/nonspecific DAT binding ratio of the basal ganglia before and after treatment with risperidone in children with TD was found, although tic symptoms were significantly improved with risperidone. These findings suggest that DAT densities are directly associated with the pathophysiology of TD, however, that the effect of risperidone on tic symptoms in children with TD is not attributed to the change of dopaminergic system.

  1. Facile fabrication of various zinc-nickel citrate microspheres and their transformation to ZnO-NiO hybrid microspheres with excellent lithium storage properties.

    Science.gov (United States)

    Xie, Qingshui; Ma, Yating; Zeng, Deqian; Wang, Laisen; Yue, Guanghui; Peng, Dong-Liang

    2015-02-16

    Zinc-nickel citrate microspheres are prepared by a simple aging process of zinc citrate solid microspheres in nickel nitrate solution. As the concentration of nickel nitrate solution increases, the morphology of the produced zinc-nickel citrate evolves from solid, yolk-shell to hollow microspheres. The formation mechanism of different zinc-nickel citrate microspheres is discussed. After annealing treatment of the corresponding zinc-nickel citrate microspheres in air, three different ZnO-NiO hybrid architectures including solid, yolk-shell and hollow microspheres can be successfully fabricated. When applied as the anode materials for lithium ion batteries, ZnO-NiO hybrid yolk-shell microspheres demonstrate the best electrochemical properties than solid and hollow counterparts. After 200th cycles, ZnO-NiO hybrid yolk-shell microspheres deliver a high reversible capacity of 1176 mA h g(-1). The unique yolk-shell configuration, the synergetic effect between ZnO and NiO and the catalytic effect of metal Ni generated by the reduction of NiO during discharging process are responsible for the excellent lithium storage properties of ZnO-NiO hybrid yolk-shell microspheres.

  2. Facile fabrication of various zinc-nickel citrate microspheres and their transformation to ZnO-NiO hybrid microspheres with excellent lithium storage properties

    Science.gov (United States)

    Xie, Qingshui; Ma, Yating; Zeng, Deqian; Wang, Laisen; Yue, Guanghui; Peng, Dong-Liang

    2015-02-01

    Zinc-nickel citrate microspheres are prepared by a simple aging process of zinc citrate solid microspheres in nickel nitrate solution. As the concentration of nickel nitrate solution increases, the morphology of the produced zinc-nickel citrate evolves from solid, yolk-shell to hollow microspheres. The formation mechanism of different zinc-nickel citrate microspheres is discussed. After annealing treatment of the corresponding zinc-nickel citrate microspheres in air, three different ZnO-NiO hybrid architectures including solid, yolk-shell and hollow microspheres can be successfully fabricated. When applied as the anode materials for lithium ion batteries, ZnO-NiO hybrid yolk-shell microspheres demonstrate the best electrochemical properties than solid and hollow counterparts. After 200th cycles, ZnO-NiO hybrid yolk-shell microspheres deliver a high reversible capacity of 1176 mA h g-1. The unique yolk-shell configuration, the synergetic effect between ZnO and NiO and the catalytic effect of metal Ni generated by the reduction of NiO during discharging process are responsible for the excellent lithium storage properties of ZnO-NiO hybrid yolk-shell microspheres.

  3. 利培酮合并氯氮平治疗难治性精神分裂症对照研究%Comparative Study on Risperidone Combined Clozapine and Risperidone in the Treatment of Refractory Schizophrenia

    Institute of Scientific and Technical Information of China (English)

    高亚娇; 安红伟; 靳红强

    2011-01-01

    Objective To compare the efficacy and safety of clozapine combined with risperidone in the treatment of refractory schizophrenia. Methods 63 cases were divided into two groups randomly,32 cases of treatment-refractory schizophrenia were treated with risperidone combined clozapine( the treatment group ) and 31 cases were treated with risperidone( the control group ). The clinical effect of patients were measured with positive and negative symptoms scale( PANSS ), and side effects were assessed with treatment emergent symptoms scale( TESS )respectively before and after 4,8,12 week treatment. Results There were significant differences in the curative effect between the two groups( P <0.05 ). After eight weeks treatment, total score of PANSS in two groups were much lower than before,the treatment group had greater decreases. After twelve weeks treatment,total score of PANSS in the treatment group was lower than that in the control group. There were statistical differences between the two groups( P <0. 05 ). Conclusion Clozapine combined with risperidone has curative effect affirmation to treat TRS,this deserves utilization in the clinical area.%目的 探讨利培酮联合氯氮平治疗难治性精神分裂症(TRS)的疗效及安全性.方法 将63例TRS患者随机分为利培酮合并氯氮平组(治疗组)32例和利培酮组(对照组)31例,两组治疗后4、8、12周均以阳性与阴性症状量表(PANSS)评定疗效,治疗意外症状量表(TESS)评定不良反应.结果 治疗组和对照组治疗TRS的疗效比较差异有统计学意义(P<0.05).治疗后8周,两组PANSS总分均较治疗前下降,治疗组下降更明显.两组治疗12周后PANSS总分比较,治疗组明显低于对照组,差异有统计学意义(P<0.05).结论 利培酮联合氯氮平治疗TRS的疗效肯定,值得临床应用.

  4. Surface modification of cyclomatrix polyphosphazene microsphere by thiol-ene chemistry and lectin recognition

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chen; Zhu, Xue-yan; Gao, Qiao-ling; Fang, Fei; Huang, Xiao-jun, E-mail: hxjzxh@zju.edu.cn

    2016-11-30

    Graphical abstract: A new synthetic route leading to polyphosphazene cyclomatrix microsphere with various functional groups has achieved via thiol-ene click modification. Herein, hexacholorocyclophosphazene (HCCP) crosslinked with bisphenol-S and 4,4′-diallyl bisphenol-S to generate broadly dispersed microspheres. Thiol-ene modification under UV irradiation not only presented high efficiency and flexibility for post-functionalization, but also imposed no harm on global morphology and crosslinked skeleton of such microspheres. - Highlights: • Functional polyphosphazene microspheres with high chemical flexibility were synthesized by thiol-ene modification. • Polyphosphazene microspheres possessed high thermal stability. • Glycosylated polyphosphazene microspheres showed affinity to lectin Con-A, which inferred potential application in biomedicine. - Abstract: A new synthetic route leading to functional polyphosphazene cyclomatrix microsphere has been developed via thiol-ene click modification. Hexacholorocyclophosphazene (HCCP) was crosslinked with both bisphenol-S and 4,4′-diallyl bisphenol-S to obtain vinyl polyphosphazene microspheres (VPZM) in order to ensure high crosslinking degree and introduce vinyl moieties. Compared to the microspheres obtained by HCCP and bisphenol-S, the size of VPZM was broadly dispersed from 400 nm to 1.40 μm. Thiol-ene click reactions were carried out to attach functional groups, such as glucosyl, carboxyl, ester and dodecyl groups onto polyphosphazene microspheres, which demonstrated no change in morphology and size after modification. Solid state NMR (SSNMR) and Fourier transform infrared spectoscopy (FT-IR) results showed that the vinyl moieties were introduced in the period of crosslinking and functionalization was also successful via click reactions. Moreover, the microspheres presented a little difference in thermal properties after modification. Concanavalin A (Con-A) fluorescent adsorption was also observed for

  5. 利培酮的臨床應用與進展%Clinical Application and Advancement of Risperidone

    Institute of Scientific and Technical Information of China (English)

    查彩慧; 肖計劃

    2001-01-01

    Objective This article reviews the mechanism, pharmcokinetics and the clinical use ofrisperidone.Materials The data base on updated literature recently. Conclusion Risperidone, a benzisoxazol derivative, is a novel typical antipsychotic agent which combines 5-hydroxytryptamine-2 (5-HT2) and dopamine-2 (D2) receptors antagonism. It can improve both positive and negative symptoms of schizophrenia. The efficacy of risperidone is well positive and effective in patients with chronic schizophrenia who had been resistant to or intolerant of conventiona neuroleptics. Risperidone can be used to treat mood disorder, obsessive-compulsive disorder, metal retardation,brain injury associated behavioral and psychiatric disorder and now it is already used in clinic widely. Risperidone is absorbed rapidly when taken orally and mainly metabolized in the liver .The principal active metabolite is 9-hydroxyrisperidone which has obvious pharmacological function. The metabolized production of risperidone is mainly discharged via urine. Risperidone has high efficacy and good safety. Now it is already used in clinic widely.%目的本文對利培酮的作用機制、藥代動力學、臨床應用和不良反應作一綜述,供同道們參考.資料所有資料均來自近幾年最新的相關文獻.結論利培酮是苯異惡唑衍生物,是一種新型的非典型抗精神病藥物.利培酮對5羥色胺Ⅱ型和多巴胺Ⅱ型受體均有拮抗作用,能有效改善精神分裂症陽性和陰性症狀,對於傳統抗精神病藥物治療失敗的難治性精神分裂症患者可首選利培酮治療.利培酮還可用於治療心境障礙、強迫症、精神發育遲滯及腦損害伴發的行為和精神障礙.利培酮口服吸收迅速,主要經肝臟代謝,在體內的代謝産物為9-羥基利培酮,亦具有藥理活性.利培酮主要通過尿液排出.利培酮的常見副反應為激越、頭痛、失眠、噁心、嗜睡等,較少出現錐體外系副反應,惡性綜合徵發

  6. Prosumer e star dei videogiochi

    Directory of Open Access Journals (Sweden)

    Giuseppe Frazzetto

    2012-03-01

    Full Text Available Su molti server di World of Warcraft ci sono toon (“personaggi” pilotati dal giocatore “famosi”. Il caso più significativo è quello di Kungen (cioè “re”, toon del giocatore svedese Thomas Bengtsson, leader prima dei Nihilum poi di un’altra celebre gilda, Ensidia. Questa peculiare fama settoriale è certamente legata alla struttura degli MMORPG, al loro essere basati su una specifica forma di socializzazione. Tuttavia ci si potrebbe chiedere: il giocatore capace di guidare un suo toon fino alla “celebrità” è un “produttore”? Un prosumer? Certo, non è “produttore” del software. Qui è in questione qualcosa di molto diverso.

  7. A case of psychosis due to Fahr's syndrome and response to behavioral disturbances with risperidone and oxcarbazepine

    Science.gov (United States)

    Faye, Abhijeet Dhawalram; Gawande, Sushil; Tadke, Rahul; Kirpekar, Vivek C.; Bhave, Sudhir H.

    2014-01-01

    Calcification of basal ganglia or Fahr's syndrome is a rare disease characterized by bilateral and symmetrical intracranial deposition of calcium mainly in cerebral basal ganglia. Motor and neuropsychiatric symptoms are prominent features. We report a case presented with a few motor symptoms, features of delirium and prominent psychiatric symptoms (disorganized behavior) predominantly evident after the improvement in delirium. Radiological findings were suggestive of bilateral basal ganglia calcification. Parathyroid hormone levels were low with no significant findings in other investigations and negative family history. Patient showed significant improvement in behavioral disturbances with risperidone, low dose of lorazepam, oxcarbazepine, and memantine. PMID:24891710

  8. Modulated Photon Emission of Eu3+ in Microsphere Cavity

    Institute of Scientific and Technical Information of China (English)

    YANG Yong; HAN Zheng-Fu; DONG Chun-Hua; XIAO Yun-Feng; GUO Guang-Can

    2006-01-01

    @@ Fused silica microsphere with a few Eu3+ ions on the equator is fabricated. The photon emission sharply modulated by whispering gallery (WG) modes is observed under excitation of 395 nm laser, which is in agreement with the prediction in theory.

  9. Calcium carbonate microspheres as carriers for the anticancer drug camptothecin

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Neng [Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow, G12 8LT (United Kingdom); State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041 (China); Department of Bio-pharmaceutical Engineering, School of Chemical Engineering, Sichuan University, Chengdu ,610065 (China); Yin, Huabing, E-mail: huabing.yin@glasgow.ac.uk [Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow, G12 8LT (United Kingdom); Ji, Bozhi; Klauke, Norbert; Glidle, Andrew [Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow, G12 8LT (United Kingdom); Zhang, Yongkui; Song, Hang [Department of Bio-pharmaceutical Engineering, School of Chemical Engineering, Sichuan University, Chengdu ,610065 (China); Cai, Lulu; Ma, Liang; Wang, Guangcheng [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041 (China); Chen, Lijuan, E-mail: lijuan17@hotmail.com [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041 (China); Wang, Wenwen [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041 (China)

    2012-12-01

    Biogenic calcium carbonate has come to the attention of many researchers as a promising drug delivery system due to its safety, pH sensitivity and the large volume of information already in existence on its medical use. In this study, we employed bovine serum albumin (BSA) as an additive to synthesize a series of porous calcium carbonate microspheres (CCMS). These spheres, identified as vaterite, are stable both in aqueous solutions and organic solvents. Camptothecin, an effective anticancer agent, was loaded into the CCMS by simple diffusion and adsorption. The camptothecin loaded CCMS showed sustained cell growth inhibitory activity and a pH dependent release of camptothecin. With a few hours, the release is negligible under physiological conditions (pH = 7.4) but almost complete at pH 4 to 6 (i.e. pHs found in lysosomes and solid tumor tissue respectively). These findings suggest that porous, biogenic calcium carbonate microspheres could be promising carriers for the safe and efficient delivery of anticancer drugs of low aqueous solubility. - Highlights: Black-Right-Pointing-Pointer BSA-doped calcium carbonate microspheres with porous structure were prepared. Black-Right-Pointing-Pointer Camptothecin was encapsulated in the spherical microparticles with encapsulation efficiency up to 11%. Black-Right-Pointing-Pointer The release of encapsulated camptothecin is pH dependent Black-Right-Pointing-Pointer In vitro studies showed an effective anticancer activity of the camptothecin- microspheres.

  10. Hydrogel microspheres from biodegradable polymers as drug delivery systems

    Science.gov (United States)

    A series of hydrogel microspheres were prepared from pectin, a hydrophilic biopolymer, and zein, a hydrophobic biopolymer, at varying weight ratios. The hydrogel formulation was conducted in the presence of calcium or other divalent metal ions at room temperature under mild conditions. Studies of ...

  11. Processing and Characterization of Sol-Gel Cerium Oxide Microspheres

    Energy Technology Data Exchange (ETDEWEB)

    McClure, Zachary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Padilla Cintron, Cristina [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-27

    Of interest to space exploration and power generation, Radioisotope Thermoelectric Generators (RTGs) can provide long-term power to remote electronic systems without the need for refueling or replacement. Plutonium-238 (Pu-238) remains one of the more promising materials for thermoelectric power generation due to its high power density, long half-life, and low gamma emissions. Traditional methods for processing Pu-238 include ball milling irregular precipitated powders before pressing and sintering into a dense pellet. The resulting submicron particulates of Pu-238 quickly accumulate and contaminate glove boxes. An alternative and dust-free method for Pu-238 processing is internal gelation via sol-gel techniques. Sol-gel methodology creates monodisperse and uniform microspheres that can be packed and pressed into a pellet. For this study cerium oxide microspheres were produced as a surrogate to Pu-238. The similar electronic orbitals between cerium and plutonium make cerium an ideal choice for non-radioactive work. Before the microspheres can be sintered and pressed they must be washed to remove the processing oil and any unreacted substituents. An investigation was performed on the washing step to find an appropriate wash solution that reduced waste and flammable risk. Cerium oxide microspheres were processed, washed, and characterized to determine the effectiveness of the new wash solution.

  12. Preparation and characterization of microspheres of albumin-heparin conjugates

    NARCIS (Netherlands)

    Kwon, Glen S.; Bae, You Han; Kim, Sung Wan; Cremers, Harry; Feijen, Jan

    1991-01-01

    Albumin-heparin microspheres have been prepared as a new drug carrier. A soluble albumin-heparin conjugate was synthesized by forming amide bonds between human serum albumin and heparin. After purification the albumin-heparin conjugate was crosslinked in a water-in-oil emulsion to form albumin-hepar

  13. Acrylic microspheres-based optosensor for visual detection of nitrite.

    Science.gov (United States)

    Noor, Nur Syarmim Mohamed; Tan, Ling Ling; Heng, Lee Yook; Chong, Kwok Feng; Tajuddin, Saiful Nizam

    2016-09-15

    A new optosensor for visual quantitation of nitrite (NO2(-)) ion has been fabricated by physically immobilizing Safranine O (SO) reagent onto a self-adhesive poly(n-butyl acrylate) [poly(nBA)] microspheres matrix, which was synthesized via facile microemulsion UV lithography technique. Evaluation and optimization of the optical NO2(-) ion sensor was performed with a fiber optic reflectance spectrophotometer. Scanning electron micrograph showed well-shaped and smooth spherical morphology of the poly(nBA) microspheres with a narrow particles size distribution from 0.6 μm up to 1.8 μm. The uniform size distribution of the acrylic microspheres promoted homogeneity of the immobilized SO reagent molecules on the microspheres' surfaces, thereby enhanced the sensing response reproducibility (<5% RSD) with a linear range obtained from 10 to 100 ppm NO2(-) ion. The micro-sized acrylic immobilization matrix demonstrated no significant barrier for diffusion of reactant and product, and served as a good solid state ion transport medium for reflectometric nitrite determination in food samples.

  14. Improved antireflection coated microspheres for biological applications of optical tweezers

    Science.gov (United States)

    Ferro, Valentina; Sonnberger, Aaron; Abdosamadi, Mohammad K.; McDonald, Craig; Schäffer, Erik; McGloin, David

    2016-09-01

    The success of optical tweezers in cellular biology1 is in part due to the wide range of forces that can be applied, from femto- to hundreds of pico-Newtons; nevertheless extending the range of applicable forces to the nanoNewton regime opens access to a new set of phenomena that currently lie beyond optical manipulation. A successful approach to overcome the conventional limits on trapping forces involves the optimization of the trapped probes. Jannasch et al.2 demonstrated that an anti-reflective shell of nanoporous titanium dioxide (aTiO2, nshell = 1.75) on a core particle made out of titanium dioxide in the anatase phase (cTiO2, ncore = 2.3) results in trappable microspheres capable to reach forces above 1 nN. Here we present how the technique can be further improved by coating the high refractive index microspheres with an additional anti-reflective shell made out of silica (SiO2). This external shell not only improves the trap stability for microspheres of different sizes, but also enables the use of functionalization techniques already established for commercial silica beads in biological experiments. We are also investigating the use of these new microspheres as probes to measure adhesion forces between intercellular adhesion molecule 1 (ICAM-1) and lymphocyte function-associated antigen 1 (LFA-1) in effector T-Cells and will present preliminary results comparing standard and high-index beads.

  15. Statistical design of position-encoded microsphere arrays.

    Science.gov (United States)

    Sarder, Pinaki; Nehorai, Arye

    2011-03-01

    We propose a microsphere array device with microspheres having controllable positions for error-free target identification. We conduct a statistical design analysis to select the optimal distance between the microspheres as well as the optimal temperature. Our design simplifies the imaging and ensures a desired statistical performance for a given sensor cost. Specifically, we compute the posterior Cramér-Rao bound on the errors in estimating the unknown target concentrations. We use this performance bound to compute the optimal design variables. We discuss both uniform and sparse concentration levels of targets, and replace the unknown imaging parameters with their maximum likelihood estimates. We illustrate our design concept using numerical examples. The proposed microarray has high sensitivity, efficient packing, and guaranteed imaging performance. It simplifies the imaging analysis significantly by identifying targets based on the known positions of the microspheres. Potential applications include molecular recognition, specificity of targeting molecules, protein-protein dimerization, high throughput screening assays for enzyme inhibitors, drug discovery, and gene sequencing.

  16. Development of activity standard for 90Y microspheres

    CSIR Research Space (South Africa)

    Mo, L

    2005-08-01

    Full Text Available 90Y is a therapeutic radiopharmaceuticals used in the treatment of liver cancer following implantation via a catheter in the hepatic artery, 90Y microspheres are embolised in the microvasculature of liver cancer where they irradiate the tumour by a...

  17. [Study on preparation process of artesunate polylactic acid microspheres].

    Science.gov (United States)

    Pan, Xu-Wang; Wang, Wei; Fang, Hong-Ying; Wang, Fu-Gen; Cai, Zhao-Bin

    2013-12-01

    This study aims to investigate the preparation process and in vitro release behavior of artesunate polylactic acid microspheres, in order to prepare an artesunate polylactic acid (PLA) administration method suitable for hepatic arterial embolization. With PLA as the material and polyvinyl alcohol (PVA) as the emulsifier, O/W emulsion/solvent evaporation method was adopted to prepare artesunate polylactic acid microspheres, and optimize the preparation process. With drug loading capacity, encapsulation efficiency and particle size as indexes, a single factor analysis was made on PLA concentration, PVA concentration, drug loading ratio and stirring velocity. Through an orthogonal experiment, the optimal processing conditions were determined as follows: PLA concentration was 9. 0% , PVA concentration was 0. 9% , drug loading ratio was 1:2 and stirring velocity was 1 000 r x min(-1). According to the verification of the optimal process, microsphere size, drug loading and entrapment rate of artesunate polylactic acid microspheres were (101.7 +/- 0.37) microm, (30.8 +/- 0.84)%, (53.6 +/- 0.62)%, respectively. The results showed that the optimal process was so reasonable and stable that it could lay foundation for further studies.

  18. Biotemplate synthesis of monodispersed iron phosphate hollow microspheres.

    Science.gov (United States)

    Cao, Feng; Li, Dongxu

    2010-03-01

    Monodispersed iron phosphate hollow microspheres with a high degree of crystallization were prepared through a facile in situ deposition method using rape pollen grains as a biotemplate. The functional group on the surface of the pollen grains could adsorb Fe(3+), which provided the nucleation sites for growth of iron phosphate nanoparticles. After being sintered at 600 degrees C for 10 h, the pollen grains were removed and iron phosphate hollow microspheres were obtained. A scanning electron microscope and x-ray diffraction were applied to characterize the morphology and crystalline structure of the pollen grains, iron phosphate-coated pollen grains and iron phosphate hollow microspheres. Differential scanning calorimetry and thermogravity analyses were performed to investigate the thermal behavior of the iron phosphate-coated pollen grains during the calcinations. Energy dispersive spectroscopy and Fourier transform infrared spectroscopy were utilized to investigate the interaction between the pollen grains and iron phosphate. The effect of the pollen wall on the surface morphology of these iron phosphate hollow microspheres was also proven in this work.

  19. Albumin-heparin microspheres as carriers for cytostatic agents

    NARCIS (Netherlands)

    Cremers, H.F.M.; Feijen, J.; Kwon, G.; Bae, Y.H.; Kim, S.W.; Noteborn, H.P.J.M.; McVie, J.G.

    1990-01-01

    Much work has been done on adriamycin-loaded albumin microspheres (Alb-MS) for chemoembolization [1–4], the rationale being that site-specific drug delivery may increase the therapeutic efficacy of the drug. Alb-Ms are being investigated because of their biocompatibility and because the degradation

  20. A microfluidic approach to assembling ordered microsphere arrays

    Science.gov (United States)

    Xu, W.; Sur, K.; Zeng, H.; Feinerman, A.; Kelso, D.; Ketterson, J. B.

    2008-07-01

    Hydrodynamic flow through an array of channels has been utilized to assemble microspheres on a flat surface. The channels, about 6 µm in lateral size, were etched through a 60 µm thick silicon wafer using deep reactive ion etching (DRIE). Droplets containing 6-8 µm fluorescent polystyrene microspheres were placed on the top side of the horizontally-oriented silicon wafer, while the bottom side was connected to a syringe that draws the fluid through the channels. In this way the microspheres are guided and secured at the inlets of the channels, and remain in place when the suction ceases. This technique, which combines favorable features such as high throughput, high resolution rate and reusability, can be a powerful platform for a new generation of protein microarrays. Antigens can be bound to the microspheres as 'targets', which can then be exposed to different fluorescence-tagged antibodies so that their binding can be confirmed. This system can also be used to study the functional roles of gene fragments and their relations to human diseases. The high throughput feature will make it possible to screen a large number of DNA fragments and identify the genetic basis of various diseases effectively.

  1. Mucoadhesive microspheres of propranolol hydrochloride for nasal delivery

    Directory of Open Access Journals (Sweden)

    Dandagi P

    2007-01-01

    Full Text Available Gelatin A microspheres of propranolol hydrochloride for intranasal systemic delivery were developed with the aim to avoid first pass metabolism, to improve the patient compliance, to use an alternative therapy to conventional dosage form, to achieve controlled blood level profiles, and to improve the therapeutic efficacy of propranolol hydrochloride in the treatment of various cardiovascular disorders and as a prophylactic for migraine. Gelatin A microspheres were prepared by emulsion crosslinking method using glutaradehyde as a crosslinking agent. Gelatin and chitosan were used as polymer and co polymer respectively. All the prepared microspheres were evaluated for physical characteristics, such as particle size, incorporation efficiency, swelling index, in vitro bioadhesion using rat jejunum and in vitro drug release in pH 6.6 phosphate buffer. Average particle size of microspheres was found to be in the size range 1-50 mm. Increase in drug and polymer concentration in the formulation increased incorporation efficiency. All the microsphers showed good bioadhesive properties and swelling indices and good sustained release of drug. The data indicates that propranolol hydrochloride release followed Higuchi′s matrix and Peppa′s model. Stability studies showed stability of formulation at all the conditions to which they were subjected.

  2. Process for fabricating doped zinc oxide microsphere gel

    Science.gov (United States)

    Arnold, Jr., Wesley D.; Bond, Walter D.; Lauf, Robert J.

    1991-01-01

    A new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel.

  3. Biotemplate synthesis of monodispersed iron phosphate hollow microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Cao Feng; Li Dongxu, E-mail: dongxuli@njut.edu.c [College of Materials Science and Engineering, Nanjing University of Technology, Jiangsu Nanjing 210009 (China)

    2010-03-15

    Monodispersed iron phosphate hollow microspheres with a high degree of crystallization were prepared through a facile in situ deposition method using rape pollen grains as a biotemplate. The functional group on the surface of the pollen grains could adsorb Fe{sup 3+}, which provided the nucleation sites for growth of iron phosphate nanoparticles. After being sintered at 600 deg. C for 10 h, the pollen grains were removed and iron phosphate hollow microspheres were obtained. A scanning electron microscope and x-ray diffraction were applied to characterize the morphology and crystalline structure of the pollen grains, iron phosphate-coated pollen grains and iron phosphate hollow microspheres. Differential scanning calorimetry and thermogravity analyses were performed to investigate the thermal behavior of the iron phosphate-coated pollen grains during the calcinations. Energy dispersive spectroscopy and Fourier transform infrared spectroscopy were utilized to investigate the interaction between the pollen grains and iron phosphate. The effect of the pollen wall on the surface morphology of these iron phosphate hollow microspheres was also proven in this work.

  4. Prediction of the effective thermal conductivity of microsphere insulation

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Ling Xue; Park, Ji Ho; Lee, Cheon Kyu; Seo, Man Su; Jeong, Sang Kwon [Cryogenic Engineering Laboratory, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-03-15

    Since glass microsphere has high crush strength, low density and small particle size, it becomes alternative thermal insulation material for cryogenic systems, such as storage and transportation tank for cryogenic fluids. Although many experiments have been performed to verify the effective thermal conductivity of microsphere, prediction by calculation is still inaccurate due to the complicated geometries, including wide range of powder diameter distribution and different pore sizes. The accurate effective thermal conductivity model for microsphere is discussed in this paper. There are four mechanisms which contribute to the heat transfer of the evacuated powder: gaseous conduction (k{sub g}), solid conduction (k{sub s}), radiation (k{sub r}) and thermal contact (k{sub c}). Among these components, k{sub g} and k{sub s} were calculated by Zehner and Schlunder model (1970). Other component values for k{sub c} and k{sub r}, which were obtained from experimental data under high vacuum conditions were added. In this research paper, the geometry of microsphere was simplified as a homogeneous solid sphere. The calculation results were compared with previous experimental data by R. Wawryk (1988), H. S. Kim (2010) and the experiment of this paper to show good agreement within error of 46%, 4.6% and 17 % for each result.

  5. PLGA and PHBV Microsphere Formulations and Solid-State Characterization

    DEFF Research Database (Denmark)

    Yang, Chiming; Plackett, David; Needham, David

    2009-01-01

    To develop and characterize the solid-state properties of poly(DL-lactic-co-glycolic acid) (PLGA) and poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid) (PHBV) microspheres for the localized and controlled release of fusidic acid (FA). The effects of FA loading and polymer composition on the mean...

  6. Hollow mesoporous titania microspheres: New technology and enhanced photocatalytic activity

    Science.gov (United States)

    Feng, Zhenliang; Wei, Wenrui; Wang, Litong; Hong, Ruoyu

    2015-12-01

    Hollow titania microspheres (HTS) were fabricated via a sol-gel process by coating the hydrolysis product of titanium tetrabutoxide (TBOT) onto the amino (-NH2) modified porous polystyrene cross-linked divinyl benzene (PS-DVB) microspheres under changing atmospheric pressure, followed by calcination in nitrogen and air atmosphere. Particularly, the atmospheric pressure was continuously and regularly changed during the formation process of PS-DVB@TiO2 microspheres. Then the TiO2 particles were absorbed into the pores and onto the surface of PS-DVB as well. The resultant HTS (around 2 μm in diameter) featured a high specific surface area (84.37 m2/g), anatase crystal and stable hollow microsphere structure, which led to high photocatalysis activity. The photocatalytic degradation of malachite green (MG) organic dye solution was conducted under ultraviolet (UV) light irradiation, which showed a high photocatalytic ability (81% of MG was degraded after UV irradiation for 88 min). Therefore, it could be potentially applied for the treatment of wastewater contaminated by organic pollutants.

  7. Chitosan-Montmorillonite microspheres: A sustainable fertilizer delivery system.

    Science.gov (United States)

    dos Santos, Bruna Rodrigues; Bacalhau, Fabiana Britti; Pereira, Tamires dos Santos; Souza, Claudinei Fonseca; Faez, Roselena

    2015-08-20

    Controlled release fertilizers are efficient tools that increase the sustainability of agricultural practices. However, the biodegradability of the matrices and the determination of the release into soil still require some investigation. This paper describes the preparation of potassium-containing microspheres based on chitosan and montmorillonite clay and the in situ soil release. The chitosan-montmorillonite microspheres were prepared using a coagulation method and different proportions of montmorillonite. The structural, thermal and morphological properties as well the water swelling and fertilizer sorption capacity were evaluated. The best formulations were applied in soil, and the fertilizer release was monitored using time-domain reflectometry (TDR). Montmorillonite clay provides better sorption properties than the chitosan microspheres because of the rough and porous surface. Due to these properties, high levels of fertilizer were sorbed onto the material. ChMMT33-containing potassium shows two specific periods of fertilizer release: the first one lasted approximately three days and was assigned to the external fertilizer on the microspheres. The second was assigned to the internal fertilizer. TDR is an important and fast tool and was used to determine the fertilizer release and the ion movement in the soil.

  8. Albumin-heparin microspheres as carriers for cytostatic agents

    NARCIS (Netherlands)

    Cremers, Harry; Feijen, Jan; Kwon, G.; Bae, Y.H.; Kim, S.W.; Noteborn, H.P.J.M.; Mcvie, J.G.

    1990-01-01

    Much work has been done on adriamycin-loaded albumin microspheres (Alb-MS) for chemoembolization [1–4], the rationale being that site-specific drug delivery may increase the therapeutic efficacy of the drug. Alb-Ms are being investigated because of their biocompatibility and because the degradation

  9. Porous metal oxide microspheres from ion exchange resin

    Science.gov (United States)

    Picart, S.; Parant, P.; Caisso, M.; Remy, E.; Mokhtari, H.; Jobelin, I.; Bayle, J. P.; Martin, C. L.; Blanchart, P.; Ayral, A.; Delahaye, T.

    2015-07-01

    This study is devoted to the synthesis and the characterization of porous metal oxide microsphere from metal loaded ion exchange resin. Their application concerns the fabrication of uranium-americium oxide pellets using the powder-free process called Calcined Resin Microsphere Pelletization (CRMP). Those mixed oxide ceramics are one of the materials envisaged for americium transmutation in sodium fast neutron reactors. The advantage of such microsphere precursor compared to classical oxide powder is the diminution of the risk of fine dissemination which can be critical for the handling of highly radioactive powders such as americium based oxides and the improvement of flowability for the filling of compaction chamber. Those millimetric oxide microspheres incorporating uranium and americium were synthesized and characterizations showed a very porous microstructure very brittle in nature which occurred to be adapted to shaping by compaction. Studies allowed to determine an optimal heat treatment with calcination temperature comprised between 700-800 °C and temperature rate lower than 2 °C/min. Oxide Precursors were die-pressed into pellets and then sintered under air to form regular ceramic pellets of 95% of theoretical density (TD) and of homogeneous microstructure. This study validated thus the scientific feasibility of the CRMP process to prepare bearing americium target in a powder free manner.

  10. Evaporation of water between two microspheres: how wetting affects drying

    Science.gov (United States)

    Cho, Kun; Kim, Yeseul; Lim, Jun; Kim, Joon Heon; Weon, Byung Mook

    2016-11-01

    When a small volume of water is confined between microparticles or nanoparticles, its evaporation behavior can be influenced by wettability of particles. This situation frequently appears in coating or printing of colloidal drops in which colloidal particles are uniformly dispersed into a liquid. To explore water evaporation between particles, here we study on evaporation dynamics of water between two microspheres by utilizing high-resolution X-ray microscopy for side views and optical microscopy for bottom views. We find that evaporating water gets pinned on microsphere surfaces, due to a force balance among air, water, and microspheres. Side and bottom views of evaporating water enable us to evaluate water curvature evolution around microspheres before and after pinning. Interestingly curvature evolution is controlled by cooperation of evaporation and wetting dynamics. This study would be useful in identifying and controlling of coating or printing for colloidal drops. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2016R1D1A1B01007133).

  11. Polyacrylate microspheres for tunable fluorimetric zinc ions sensor.

    Science.gov (United States)

    Woźnica, Emilia; Maksymiuk, Krzysztof; Michalska, Agata

    2014-01-07

    A novel concept of optical fluorimetric sensing using polymeric microspheres is explored on example of zinc ions sensors. The novel approach proposed uses the advantage of concomitant presence in a microsphere of two compounds: a receptor, fluorescently silent complexing ligand and an optical transducer, fluorescent compound. Binding of the analyte by the ligand affects its absorption spectrum, leading to decrease of the free ligand absorption and increase of complex absorption band. The decrease of free ligand absorption exposes emission of the transducer, yielding increase in fluorescence intensity on analyte concentration increase. This approach was verified experimentally using Zn(2+) as a model analyte, the fluorimetric sensor obtained uses 1-(2-pyridylazo)-2-naphthol (PAN) as analyte sensitive receptor and pyrene as optical transducer. In the absence of zinc ions in the sample emission of pyrene embedded in the spheres was significantly quenched, whereas increase of Zn(2+) ions concentration in the sample resulted in dependence of fluorescence intensity on logarithm of zinc ions concentration in extraordinary wide range, from 10(-7) to 0.1 M. The response mechanism was explained by surface accumulation of zinc ion-PAN complex on the microsphere/sample solution interface. It was also shown that introduction of cation-exchanging sites to the microspheres significantly alters the responses pattern leading to high sensitivity over relatively limited concentration range (3-4 orders of magnitude). In the latter case the observed responses can be tuned to occur in chosen concentration range, simply by adjusting sample pH.

  12. BIOCOMPATIBLE FLUORESCENT MICROSPHERES: SAFE PARTICLES FOR MATERIAL PENETRATION STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    farquar, G; Leif, R

    2008-09-12

    Biocompatible polymers with hydrolyzable chemical bonds are being used to produce safe, non-toxic fluorescent microspheres for material penetration studies. The selection of polymeric materials depends on both biocompatibility and processability, with tailored fluorescent properties depending on specific applications. Microspheres are composed of USFDA-approved biodegradable polymers and non-toxic fluorophores and are therefore suitable for tests where human exposure is possible. Micropheres are being produced which contain unique fluorophores to enable discrimination from background aerosol particles. Characteristics that affect dispersion and adhesion can be modified depending on use. Several different microsphere preparation methods are possible, including the use of a vibrating orifice aerosol generator (VOAG), a Sono-Tek atomizer, an emulsion technique, and inkjet printhead. The advantages and disadvantages of each method will be presented and discussed in greater detail along with fluorescent and charge properties of the aerosols. Applications for the fluorescent microspheres include challenges for biodefense system testing, calibrants for biofluorescence sensors, and particles for air dispersion model validation studies.

  13. Inflammation in Patients with Schizophrenia: the Therapeutic Benefits of Risperidone Plus Add-On Dextromethorphan

    Science.gov (United States)

    Chen, Shiou-Lan; Lee, Sheng-Yu; Chang, Yun-Hsuan; Chen, Shih-Heng; Chu, Chun-Hsieh; Tzeng, Nian-Sheng; Lee, I-Hui; Chen, Po-See; Yeh, Tzung Lieh; Huang, San-Yuan; Yang, Yen-Kuang; Lu, Ru-Band; Hong, Jau-Shyong

    2013-01-01

    Objectives Increasing evidence suggests that inflammation contributes to the etiology and progression of schizophrenia. Molecules that initiate inflammation, such as virus- and toxin-induced cytokines, are implicated in neuronal degeneration and schizophrenia-like behavior. Using therapeutic agents with anti-inflammatory or neurotrophic effects may be beneficial for treating schizophrenia. Methods One hundred healthy controls and 95 Han Chinese patients with schizophrenia were tested in this double-blind study. Their PANSS scores, plasma interleukin (IL)-1β, TNF-α and brain-derived neurotrophic factor (BDNF) levels were measured before and after pharmacological treatment. Results Pretreatment, plasma levels of IL-1β and TNF-α were significantly higher in patients with schizophrenia than in controls, but plasma BDNF levels were significantly lower. Patients were treated with the atypical antipsychotic risperidone (Risp) only or with Risp+add-on dextromethorphan (DM). PANSS scores and plasma IL-1β levels significantly decreased, but plasma TNF-α and BDNF levels significantly increased after 11 weeks of Risp treatment. Patients in the Risp+DM group showed a greater and earlier reduction of symptoms than did those in the Risp-only group. Moreover, Risp+DM treatment attenuated Risp-induced plasma increases in TNF-α. Conclusion Patients with schizophrenia had a high level of peripheral inflammation and a low level of peripheral BDNF. Long-term Risp treatment attenuated inflammation and potentiated the neurotrophic function but also produced a certain degree of toxicity. Risp+DM was more beneficial and less toxic than Risp-only treatment. PMID:22730040

  14. Study on the luminescence behavior of sulfobutylether-β-cyclodextrin with risperidone and its analytical application

    Science.gov (United States)

    Wu, Min; Chen, Donghua; Song, Zhenghua

    2012-10-01

    The interaction of sulfobutylether-β-cyclodextrin (SBE-β-CD) with risperidone (RISP) was first described with luminol-SBE-β-CD chemiluminescence (CL) system by flow injection analysis (FIA). In luminol-SBE-β-CD CL system, the 1:1 SBE-β-CD⋯luminol∗ complexation could enhance CL intensity of luminol and produce the effect of complexation enhancement of CL (CEC). It was found that RISP could quench the CL intensity of SBE-β-CD⋯luminol∗ and caused the effect of complexation enhancement of quenching (CEQ), the formation constant KR-CD 3.4 × 104 L mol-1 and the stoichiometric ratio 1:1 of RISP⋯SBE-β-CD complex were obtained by the proposed CL model. Association degree α 0.036 of RISP⋯SBE-β-CD complex was also given by CL method. Based on the linear relationship to the decrement of luminol-SBE-β-CD-RISP CL intensity and the logarithm of RISP concentration, RISP also can be quantified in the linear range of 3.0-500.0 nmol L-1 with a detection limit of 1.0 nmol L-1 (3σ). The proposed method was successfully applied to monitoring excreted RISP in human urine. It was found that RISP reached its maximum after oral administration for 1.5 h with the total excretion of 14.26% within 8.5 h; the elimination rate constant k and half-life time t1/2 were 0.474 and 1.5 h, respectively.

  15. Distinct neurobehavioral consequences of prenatal exposure to sulpiride (SUL) and risperidone (RIS) in rats.

    Science.gov (United States)

    Zuo, Jing; Liu, Zhening; Ouyang, Xuan; Liu, Haihong; Hao, Yihui; Xu, Lin; Lu, Xiao-Hong

    2008-02-15

    Antipsychotic treatment during pregnancy is indicated when risk of drug exposure to the fetus is outweighed by the untreated psychosis in the mother. Although increased risk of congenital malformation has not been associated with most available antipsychotic drugs, there is a paucity of knowledge on the subtle neurodevelopmental and behavioral consequences of prenatal receptor blockade by these drugs. In the present study, antipsychotic drugs, sulpiride (SUL, a selective D2 receptor antagonist) and risperidone (RIS, a D2/5HT2 receptor antagonist) were administered to pregnant Sprague-Dawley dams from gestational day 6 to 18. Both RIS and SUL prenatal exposed rats had lower birth body weights compared to controls. RIS exposure had a significant main effect to retard body weight growth in male offspring until postnatal day (PND) 60. Importantly, water maze tests revealed that SUL prenatal exposure impaired visual cue response in visual task performance (stimulus-response, S-R memory), but not place response as reflected in hidden platform task (spatial memory acquisition and retention). In addition, prenatal SUL treatment reduced spontaneous activity as measured in open field. Both behavioral deficits suggest that SUL prenatal exposure may lead to subtle disruption of striatum development and related learning and motor systems. RIS exposure failed to elicit deficits in both water maze tasks and increased rearing in open field test. These results suggest prenatal exposure to SUL and RIS may produce lasting effects on growth, locomotion and memory in rat offspring. And the differences may exist in the effects of antipsychotic drugs which selectively block dopamine D2 receptors (SUL) as compared to second generation drugs (RIS) that potently antagonize serotonin and dopamine receptors.

  16. Development of Nutraceutical Emulsions as Risperidone Delivery Systems: Characterization and Toxicological Studies.

    Science.gov (United States)

    Igartúa, Daniela Edith; Calienni, María Natalia; Feas, Daniela Agustina; Chiaramoni, Nadia Silvia; Valle Alonso, Silvia Del; Prieto, María Jimena

    2015-12-01

    Emulsions are gaining increasing interest to be applied as drug delivery systems. The main goal of this work was the formulation of an oil/water nutraceutical emulsion (NE) for oral administration, enriched in omega 3 (ω3) and omega 6 (ω6), and able to encapsulate risperidone (RISP), an antipsychotic drug widely used in the treatment of autism spectrum disorders (ASD). RISP has low solubility in aqueous medium and poor bioavailability because of its metabolism and high protein binding. Coadministration of ω3, ω3, and vitamin E complexed with RISP might increase its bioavailability and induce a synergistic effect on the treatment of ASD. Here, we developed an easy and quick method to obtain NEs and then optimized them. The best formulation was chosen after characterization by particle size, defects of the oil-in-water interface, zeta potential (ZP), and in vitro drug release. The formulation selected was stable over time, with a particle size of around 3 μm, a ZP lower than -20 mV and controlled drug release. To better understand the biochemical properties of the formulation obtained, we studied in vitro toxicity in the Caco-2 cell line. After 4 h of treatment, an increase in cellular metabolism was observed for all RISP concentrations, but emulsions did not change their metabolic rate, except at the highest concentration without drug (25 μg/mL), which showed a significant reduction in metabolism respect to the control. Additionally, locomotor activity and heart rate in zebrafish were measured as parameters of in vivo toxicity. Only the highest concentration (0.625 μg/mL) showed a cardiotoxic effect, which corresponds to the decrease in spontaneous movement observed previously. As all the materials contained in the formulations were US FDA approved, the NE selected would be good candidate for clinical trials.

  17. Inflammation in patients with schizophrenia: the therapeutic benefits of risperidone plus add-on dextromethorphan.

    Science.gov (United States)

    Chen, Shiou-Lan; Lee, Sheng-Yu; Chang, Yun-Hsuan; Chen, Shih-Heng; Chu, Chun-Hsieh; Tzeng, Nian-Sheng; Lee, I-Hui; Chen, Po-See; Yeh, Tzung Lieh; Huang, San-Yuan; Yang, Yen-Kuang; Lu, Ru-Band; Hong, Jau-Shyong

    2012-09-01

    Increasing evidence suggests that inflammation contributes to the etiology and progression of schizophrenia. Molecules that initiate inflammation, such as virus- and toxin-induced cytokines, are implicated in neuronal degeneration and schizophrenia-like behavior. Using therapeutic agents with anti-inflammatory or neurotrophic effects may be beneficial for treating schizophrenia. One hundred healthy controls and 95 Han Chinese patients with schizophrenia were tested in this double-blind study. Their PANSS scores, plasma interleukin (IL)-1β, tumor necrosis factor-α (TNF-α) and brain-derived neurotrophic factor (BDNF) levels were measured before and after pharmacological treatment. Pretreatment, plasma levels of IL-1β and TNF-α were significantly higher in patients with schizophrenia than in controls, but plasma BDNF levels were significantly lower. Patients were treated with the atypical antipsychotic risperidone (Risp) only or with Risp+ dextromethorphan (DM). PANSS scores and plasma IL-1β levels significantly decreased, but plasma TNF-α and BDNF levels significantly increased after 11 weeks of Risp treatment. Patients in the Risp+ DM group showed a greater and earlier reduction of symptoms than did those in the Risp-only group. Moreover, Risp+ DM treatment attenuated Risp-induced plasma increases in TNF-α. Patients with schizophrenia had a high level of peripheral inflammation and a low level of peripheral BDNF. Long-term Risp treatment attenuated inflammation and potentiated the neurotrophic function but also produced a certain degree of toxicity. Risp+ DM was more beneficial and less toxic than Risp-only treatment. Protocol Record: HR-93-50; NCT01189006; URL: http://www.clinicaltrials.gov.

  18. A doxorubicin delivery system: Samarium/mesoporous bioactive glass/alginate composite microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ying, E-mail: yingzhang@suda.edu.cn; Wang, Xiang; Su, Yanli; Chen, Dongya; Zhong, Wenxing

    2016-10-01

    Samarium (Sm) incorporated mesoporous bioactive glasses (MBG) microspheres have been prepared using the method of alginate cross-linking with Ca{sup 2+} ions. The in vitro bioactivities of Sm/MBG/alginate microspheres were studied by immersing in simulated body fluid (SBF) for various periods. The results indicated that the Sm/MBG/alginate microspheres have a faster apatite formation rate on the surface. To investigate their delivery properties further, doxorubicin (DOX) was selected as a model drug. The results showed that the Sm/MBG/alginate microspheres exhibit sustained DOX delivery, and their release mechanism is controlled by Fickian diffusion according the Higuchi model. In addition, the delivery of DOX from Sm/MBG/alginate microspheres can be dominated by changing the doping concentration of Sm and the values of pH microenvironment. These all revealed that this material is a promising candidate for the therapy of bone cancer. - Graphical abstract: The schematic illustration of controlled DOX release from the Sm/MBG alginate microspheres. Display Omitted - Highlights: • Sm/MBG/alginate microspheres were synthesized by alginate cross-linking with Ca{sup 2+}. • Sm/MBG/alginate microspheres demonstrate apatite formation ability. • Sm/MBG/alginate microspheres possess a sustained release of anti-cancer drug (DOX). • Sm/MBG/alginate microspheres have positive potential for the therapy of bone cancer.

  19. Sustained Release Floating Microspheres Of Acyclovir: Formulation, Optimization, Characterization And In Vitro Evaluation

    Directory of Open Access Journals (Sweden)

    Parmar Kunal Vinodbhai

    2011-03-01

    Full Text Available The aim of the present work was to prepare floating microspheres of acyclovir to prolong residence time in stomach and to sustain the release of acyclovir. Acyclovir loaded floating microspheres were prepared by double emulsion solvent evaporation method. The 32 full factorial design was applied to optimize the formulation. The resultant microspheres were evaluated for average particle size, percentage encapsulation efficiency, in vitro drug release and model fitting kinetics. Scanning electron microscopy, Fourier transform infrared (FTIR spectroscopy and differential scanning calorimetry were used to investigate the physical state of the drug in the microspheres. The particle size of microspheres was in the range of 275-340 µm. Percentage encapsulation efficiency was between 59%-77% w/w. Microspheres remained buoyant for more than about 12 h. The results of FT-IR spectroscopy and differential scanning calorimetry indicated the stable character of acyclovir in microspheres and also revealed absence of drugpolymer interaction. The in vitro drug release study showed that acyclovir release from the microspheres was slow and sustained for more than about 10 h. Drug release followed Korsemeyer-peppas model. The results of factorial batches revealed that the concentration of ethyl cellulose and stirring speed significantly affected drug encapsulation efficiency and particle size of the microspheres. Thus we can conclude that floating microspheres can successfully be developed to sustain the drug release.

  20. Synthesis and catalytic performance of SiO2@Ni and hollow Ni microspheres

    Science.gov (United States)

    Liu, Xin; Liu, Yanhua; Shi, Xueting; Yu, Zhengyang; Feng, Libang

    2016-11-01

    Nickel (Ni) catalyst has been widely used in catalytic reducing reactions such as catalytic hydrogenation of organic compounds and catalytic reduction of organic dyes. However, the catalytic efficiency of pure Ni is low. In order to improve the catalytic performance, Ni nanoparticle-loaded microspheres can be developed. In this study, we have prepared Ni nanoparticle-loaded microspheres (SiO2@Ni) and hollow Ni microspheres using two-step method. SiO2@Ni microspheres with raspberry-like morphology and core-shell structure are synthesized successfully using SiO2 microsphere as a template and Ni2+ ions are adsorbed onto SiO2 surfaces via electrostatic interaction and then reduced and deposited on surfaces of SiO2 microspheres. Next, the SiO2 cores are removed by NaOH etching and the hollow Ni microspheres are prepared. The NaOH etching time does no have much influence on the crystal structure, shape, and surface morphology of SiO2@Ni; however, it can change the phase composition evidently. The hollow Ni microspheres are obtained when the NaOH etching time reaches 10 h and above. The as-synthesized SiO2@Ni microspheres exhibit much higher catalytic performance than the hollow Ni microspheres and pure Ni nanoparticles in the catalytic reduction of methylene blue. Meanwhile, the SiO2@Ni catalyst has high stability and hence it can be recycled for reuse.

  1. Enhanced autonomic shutdown of Li-ion batteries by polydopamine coated polyethylene microspheres

    Science.gov (United States)

    Baginska, Marta; Blaiszik, Benjamin J.; Rajh, Tijana; Sottos, Nancy R.; White, Scott R.

    2014-12-01

    Thermally triggered autonomic shutdown of a Lithium-ion (Li-ion) battery is demonstrated using polydopamine (PDA)-coated polyethylene microspheres applied onto a battery anode. The microspheres are dispersed in a buffered 10 mM dopamine salt solution and the pH is raised to initiate the polymerization and coat the microspheres. Coated microspheres are then mixed with an aqueous binder, applied onto a battery anode surface, dried, and incorporated into Li-ion coin cells. FTIR and Raman spectroscopy are used to verify the presence of the polydopamine on the surface of the microspheres. Scanning electron microscopy is used to examine microsphere surface morphology and resulting anode coating quality. Charge and discharge capacity, as well as impedance, are measured for Li-ion coin cells as a function of microsphere content. Autonomous shutdown is achieved by applying 1.7 mg cm-2 of PDA-coated microspheres to the electrode. The PDA coating significantly reduces the mass of microspheres for effective shutdown compared to our prior work with uncoated microspheres.

  2. Evaluation of the Intestinal Colonizing Potential and Immunomodulating Capacity of Lactobacilli Microspheres.

    Science.gov (United States)

    Cotta, Karyn I; Addo, Richard T; D'Souza, Martin J

    2016-05-01

    Lactobacilli species get degraded by acidic conditions in the stomach. Thus, the objective of this study was to (1) formulate and characterize gastro-resistant Lactobacilli microspheres and (2) evaluate the ability of Lactobacilli microspheres to colonize the intestine and their capacity to have an immunomodulating effect in vivo. The product yield and the encapsulation efficiency were 45% and 100%, respectively. The average microsphere particle size was 5 μm. Lactobacilli microspheres were most stable at 4°C and showed a better suspendibility in distilled water. Without encapsulation, the viability of bacteria decreased within 30 min. In the case of Lactobacilli microspheres, no Lactobacilli were released in the first 3 h, and highest release was observed at 4 h, thus, suggesting the significance of encapsulation of Lactobacilli. Lactobacilli microspheres maintained intestinal colonization only during the dosing period, and the serum IgG, serum IgA, fecal, intestinal, nasal IgA, and the serum interleukin-1β levels were higher in the Lactobacilli microsphere group compared with the blank microsphere and the lactobacilli solution group, suggesting that the Lactobacilli microspheres were more gastro-resistant and, hence, showed positive effects compared with the Lactobacilli solution. However, the Lactobacilli microspheres did not have a significant effect on the tumor necrosis factor-α levels.

  3. 利培酮微球和利培酮治疗精神分裂症对照研究%A comparative study of risperidone long-acting injection and risperidone in treatment for patients with schizophrenia

    Institute of Scientific and Technical Information of China (English)

    苏磊; 孙自豪; 冯凡; 李龙飞

    2015-01-01

    Objective To explore the efficacy and safety of risperidone long-acting injection and risperidone in treatment for patients with schizophrenia.Methods A total of 160 patients with schizophrenia were randomly divided into study group ( 80 cases) with risperidone long-acting injection and control group(80 cases) with risperidone for treatment of 3 months.They were assessed with Positive and Negative Syndrome Scale(PANSS), Clinical Global Impression-Severity of Illness(CGI-S), Clinical Global Impression-Global Improvement(CGI-I) and Extrapyramidal Symptom Rating Scale(ESRS) at baseline , 1st month end, 2nd month end and 3rd month end of treatment.Results At 1st month end, 2nd month end and 3rd month end of treatment, the factors and total scores of PANSS in two groups were all significantly lower than those at baseline(P<0.05).At 2nd month end and 3rd month end of treatment, the factors and total scores of PANSS and CGI in study group were all significantly lower than those in control group(P<0.05).At 1st month end, 2nd month end and 3rd month end of treatment, the scores of ESRS in study group were significantly lower than those in control group(P<0.05).Conclusion It’s effective and safe for risperidone long-acting injection to treat the patients with schizophrenia.%目的:探寻利培酮微球和利培酮治疗精神分裂症患者的疗效和安全性。方法将160例精神分裂症患者随机分为研究组和对照组各80例,研究组用利培酮微球系统治疗,对照组用利培酮系统治疗,共3个月,在基线和治疗后1、2、3个月末应用阳性和阴性综合征量表( PANSS)、临床疗效总评量表-病情严重程度( CGI-S)、临床疗效总评量表-疗效总评( CGI-I)、锥体外系症状评定量表( ESRS)评价。结果两组在治疗后第1、2、3个月末的PANSS评分均低于基线时相应评分(P<0.05)。在治疗后第2、3个月末,研究组PANSS评分以及CGI

  4. Hydrothermal synthesis and photocatalytic performance of hierarchical Bi{sub 2}MoO{sub 6} microspheres using BiOI microspheres as self-sacrificing templates

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Ming; Zhang, Wei-De, E-mail: zhangwd@scut.edu.cn

    2015-07-15

    Bi{sub 2}MoO{sub 6} hierarchical microspheres were successfully prepared through phase transformation from BiOI microspheres with the assistance of sodium citrate under hydrothermal condition. The possible formation mechanism for the conversion of BiOI to Bi{sub 2}MoO{sub 6} is discussed here. After being annealed at 300 °C for 2 h, the obtained Bi{sub 2}MoO{sub 6} microspheres exhibited remarkably enhanced photocatalytic activity towards the degradation of rhodamine B and phenol. The superior catalytic performance can be attributed to its larger surface area and higher crystallinity. In addition, Bi{sub 2}MoO{sub 6} microspheres are stable during the degradation reaction and can be used repeatedly. - Graphical abstract: Bi{sub 2}MoO{sub 6} hierarchical microspheres were successfully prepared through a facile partial anion exchange strategy using BiOI microspheres as self-sacrificing templates. The Bi{sub 2}MoO{sub 6} microspheres show high visible light photocatalytic activity. - Highlights: • Bi{sub 2}MoO{sub 6} microspheres were prepared via self-sacrificing template anion exchange. • Sodium citrate-assisted anion exchange for preparation of Bi{sub 2}MoO{sub 6} photocatalyst. • Bi{sub 2}MoO{sub 6} catalysts show high visible light photocatalytic activity.

  5. Alginate gel-coated oil-entrapped alginate-tamarind gum-magnesium stearate buoyant beads of risperidone.

    Science.gov (United States)

    Bera, Hriday; Boddupalli, Shashank; Nandikonda, Sridhar; Kumar, Sanoj; Nayak, Amit Kumar

    2015-01-01

    A novel alginate gel-coated oil-entrapped calcium-alginate-tamarind gum (TG)-magnesium stearate (MS) composite floating beads was developed for intragastric risperidone delivery with a view to improving its oral bioavailability. The TG-blended alginate core beads containing olive oil and MS as low-density materials were accomplished by ionotropic gelation technique. Effects of polymer-blend ratio (sodium alginate:TG) and crosslinker (CaCl2) concentration on drug entrapment efficiency (DEE, %) and cumulative drug release after 8 h (Q8h, %) were studied to optimize the core beads by a 3(2) factorial design. The optimized beads (F-O) exhibited DEE of 75.19±0.75% and Q8h of 78.04±0.38% with minimum errors in prediction. The alginate gel-coated optimized beads displayed superior buoyancy and sustained drug release property. The drug release profiles of the drug-loaded uncoated and coated beads were best fitted in Higuchi kinetic model with Fickian and anomalous diffusion driven mechanisms, respectively. The optimized beads yielded a notable sustained drug release profile as compared to marketed immediate release preparation. The uncoated and coated Ca-alginate-TG-MS beads were also characterized by SEM, FTIR and P-XRD analyses. Thus, the newly developed alginate-gel coated oil-entrapped alginate-TG-MS composite beads are suitable for intragastric delivery of risperidone over a prolonged period of time.

  6. Use of haloperidol and risperidone in highly aggressive Swiss Webster mice by applying the model of spontaneous aggression (MSA).

    Science.gov (United States)

    Fragoso, Viviane Muniz da Silva; Hoppe, Luanda Yanaan; de Araújo-Jorge, Tânia Cremonini; de Azevedo, Marcos José; Campos, Jerônimo Diego de Souza; Cortez, Célia Martins; de Oliveira, Gabriel Melo

    2016-03-15

    Aggression is defined as the act in which an individual intentionally harms or injures another of their own species. Antipsychotics are a form of treatment used in psychiatric routine. They have been used for decades in treatment of patients with aggressive behavior. Haloperidol and risperidone promote the control of psychiatric symptoms, through their respective mechanisms of action. Experimental models are obtained by behavioral, genetic, and pharmacological manipulations, and use a reduced number of animals. In this context, we applied the model of spontaneous aggression (MSA), originating the presence of highly aggressive mice (AgR) when reassembled in adulthood. We administered haloperidol and risperidone in escalating doses, for ten consecutive days. Using positive and negative control groups, we evaluated the effectiveness of these drugs and the reversal of the aggressive behavior, performing the tail suspension test (TST) and open field test (OFT) on 10th day of treatment and 10 days after its discontinuation. The results showed that both antipsychotic drugs were effective in AgR and reversed the aggressive phenotype, reducing the number of attacks by AgR and the extent of lesions in the subordinate mice (AgD) exposed to the pattern of aggressive behavior (PAB) of the aggressors. This conclusion is based on the reduction in the animals' motor and exploratory activity, and on the reversal of patterns of aggressive behavior. The association between the MSA and experiments with other therapeutic protocols and different antipsychotics can be an important methodology in the study of aggressive behavior in psychiatric patients.

  7. Risperidone reverses the spatial object recognition impairment and hippocampal BDNF-TrkB signalling system alterations induced by acute MK-801 treatment.

    Science.gov (United States)

    Chen, Guangdong; Lin, Xiaodong; Li, Gongying; Jiang, Diego; Lib, Zhiruo; Jiang, Ronghuan; Zhuo, Chuanjun

    2017-03-01

    The aim of the present study was to investigate the effects of a commonly-used atypical antipsychotic, risperidone, on alterations in spatial learning and in the hippocampal brain-derived neurotrophic factor (BDNF)-tyrosine receptor kinase B (TrkB) signalling system caused by acute dizocilpine maleate (MK-801) treatment. In experiment 1, adult male Sprague-Dawley rats subjected to acute treatment of either low-dose MK801 (0.1 mg/kg) or normal saline (vehicle) were tested for spatial object recognition and hippocampal expression levels of BDNF, TrkB and the phophorylation of TrkB (p-TrkB). We found that compared to the vehicle, MK-801 treatment impaired spatial object recognition of animals and downregulated the expression levels of p-TrkB. In experiment 2, MK-801- or vehicle-treated animals were further injected with risperidone (0.1 mg/kg) or vehicle before behavioural testing and sacrifice. Of note, we found that risperidone successfully reversed the deleterious effects of MK-801 on spatial object recognition and upregulated the hippocampal BDNF-TrkB signalling system. Collectively, the findings suggest that cognitive deficits from acute N-methyl-D-aspartate receptor blockade may be associated with the hypofunction of hippocampal BDNF-TrkB signalling system and that risperidone was able to reverse these alterations.

  8. A Double-Blind, Placebo-Controlled Study of Risperidone for the Treatment of Adolescents and Young Adults with Anorexia Nervosa: A Pilot Study

    Science.gov (United States)

    Hagman, Jennifer; Gralla, Jane; Sigel, Eric; Ellert, Swan; Dodge, Mindy; Gardner, Rick; O'Lonergan, Teri; Frank, Guido; Wamboldt, Marianne Z.

    2011-01-01

    Objective: The purpose of this double-blind, placebo-controlled exploratory pilot study was to evaluate the safety and efficacy of risperidone for the treatment of anorexia nervosa. Method: Forty female subjects 12 to 21 years of age (mean, 16 years) with primary anorexia nervosa in an eating disorders program were randomized to receive…

  9. Schizophrenic patients treated with clozapine or olanzapine perform better on theory of mind tasks than those treated with risperidone or typical antipsychotic medications.

    Science.gov (United States)

    Savina, Ioulia; Beninger, Richard J

    2007-08-01

    Theory of mind (ToM), the ability to attribute mental states to others, is associated with medial prefrontal cortical (mPFC) activity and is impaired in schizophrenia. Olanzapine or clozapine but not typical antipsychotics or risperidone preferentially affect c-fos expression in mPFC in animals. We tested the hypothesis that schizophrenic patients treated with different antipsychotics would perform differently on ToM tasks. Groups receiving Typicals (n=23), Clozapine (n=18), Olanzapine (n=20) or Risperidone (n=23) and a Control group of healthy volunteers (n=24) were matched for age, gender, handedness and education. ToM functioning was assessed with picture sequence, second-order belief and faux-pas tests. Schizophrenic groups performed similarly to controls on non-ToM conditions. The Olanzapine and Clozapine groups performed similarly to Controls on ToM tasks. The Typicals and Risperidone groups performed worse than the other groups on ToM tasks. We concluded that ToM performance of schizophrenic patients is influenced by the antipsychotic they are taking. Our results suggest that olanzapine or clozapine but not typicals or risperidone may improve or protect ToM ability.

  10. Risperidone-Induced Weight Gain in Referred Children with Autism Spectrum Disorders Is Associated with a Common Polymorphism in the 5-Hydroxytryptamine 2C Receptor Gene

    NARCIS (Netherlands)

    Hoekstra, Pieter J.; Troost, Pieter W.; Lahuis, Bertine E.; Mulder, Hans; Mulder, Erik J.; Franke, Barbara; Buitelaar, Jan K.; Anderson, George M.; Scahill, Lawrence; Minderaa, Ruud B.

    2010-01-01

    Weight gain is an important adverse effect of risperidone, but predictors of significant weight gain have yet to be identified in pediatric patients. Here, we investigated differences between age-and gender-normed body mass index-standardized z scores at baseline and after 8 weeks of open-label, fle

  11. Risperidone-Induced Weight Gain in Referred Children with Autism Spectrum Disorders Is Associated with a Common Polymorphism in the 5-Hydroxytryptamine 2C Receptor Gene.

    NARCIS (Netherlands)

    Hoekstra, P.J.; Troost, P.W.; Lahuis, B.E.; Mulder, H.; Mulder, E.J.H.; Franke, B.; Buitelaar, J.K.; Anderson, G.M.; Scahill, L.; Minderaa, R.B.

    2010-01-01

    Abstract Weight gain is an important adverse effect of risperidone, but predictors of significant weight gain have yet to be identified in pediatric patients. Here, we investigated differences between age- and gender-normed body mass index-standardized z scores at baseline and after 8 weeks of open-

  12. A Double-Blind, Placebo-Controlled Study of Risperidone for the Treatment of Adolescents and Young Adults with Anorexia Nervosa: A Pilot Study

    Science.gov (United States)

    Hagman, Jennifer; Gralla, Jane; Sigel, Eric; Ellert, Swan; Dodge, Mindy; Gardner, Rick; O'Lonergan, Teri; Frank, Guido; Wamboldt, Marianne Z.

    2011-01-01

    Objective: The purpose of this double-blind, placebo-controlled exploratory pilot study was to evaluate the safety and efficacy of risperidone for the treatment of anorexia nervosa. Method: Forty female subjects 12 to 21 years of age (mean, 16 years) with primary anorexia nervosa in an eating disorders program were randomized to receive…

  13. Risk of Hyperprolactinemia and Sexual Side Effects in Males 10-20 Years Old Diagnosed with Autism Spectrum Disorders or Disruptive Behavior Disorder and Treated with Risperidone

    NARCIS (Netherlands)

    Roke, Yvette; Buitelaar, Jan K.; Boot, Annemieke M.; Tenback, Diederik; van Harten, Peter N.

    2012-01-01

    Objective: The aim of this study was to investigate the long-term treatment effects of risperidone on prolactin levels and prolactin-related side effects in pubertal boys with autism spectrum disorders (ASD) and disruptive behavior disorders (DBD). Method: Physical healthy 10-20-year-old males with

  14. A randomized, double-blind, placebo-controlled study of risperidone maintenance treatment in children and adolescents with disruptive behavior disorders.

    NARCIS (Netherlands)

    Reyes, M.; Buitelaar, J.K.; Toren, P.; Augustyns, I.; Eerdekens, M.

    2006-01-01

    OBJECTIVE: The authors compared the effects of maintenance versus withdrawal of risperidone treatment in children and adolescents with symptoms of disruptive behavior disorder. METHOD: Patients with disruptive behavior disorder (5-17 years of age and a range of intellect) who had responded to risper

  15. Literature Analysis of 153 Cases of Adverse Drug Reactions Induced by Risperidone%153例利培酮致不良反应的文献分析

    Institute of Scientific and Technical Information of China (English)

    周秋娟; 吴晓燕; 陈颖; 巢楠; 瞿发林; 黄家富

    2014-01-01

    Objective To study the clinical features of adverse reaction induced by risperidone. Methods 122 case reports of adverse drug reaction due to risperidone from 2000 to 2012 in China were collected and analyzed, which involved 153 patients. Results The adverse reactions of risperidone were correlated with individual differences, which mainly occurred in central and peripheral nervous system. Conclusion Pay attention to physical status of patients when use risperidone,slowly increase the dose and comply with the individualized principle.%目的:综合分析利培酮所致不良反应的临床特征。方法对2000~2012年国内文献中有关利培酮所致不良反应的病例报道122篇涉及153例患者进行汇总分析。结果利培酮所致不良反应主要累及的系统-器官为中枢及外周神经系统,不良反应的发生与患者的个体差异有关。结论利培酮用药时应注意给药速度不宜过快,遵循个体化原则,关注患者的身体状况。

  16. Differences in frontal cortical activation by a working memory task after substitution of risperidone for typical antipsychotic drugs in patients with schizophrenia

    OpenAIRE

    Honey, Garry D; Edward T Bullmore; Soni, William; Varatheesan, Malini; Williams, Steve C.R.; Sharma, Tonmoy

    1999-01-01

    Antipsychotic drug treatment of schizophrenia may be complicated by side effects of widespread dopaminergic antagonism, including exacerbation of negative and cognitive symptoms due to frontal cortical hypodopaminergia. Atypical antipsychotics have been shown to enhance frontal dopaminergic activity in animal models. We predicted that substitution of risperidone for typical antipsychotic drugs in the treatment of schizophrenia would be associated with enhanced functional activation of frontal...

  17. MRI visible drug eluting magnetic microspheres for transcatheter intra-arterial delivery to liver tumors.

    Science.gov (United States)

    Kim, Dong-Hyun; Chen, Jeane; Omary, Reed A; Larson, Andrew C

    2015-01-01

    Magnetic resonance imaging (MRI)-visible amonafide-eluting alginate microspheres were developed for targeted arterial-infusion chemotherapy. These alginate microspheres were synthesized using a highly efficient microfluidic gelation process. The microspheres included magnetic clusters formed by USPIO nanoparticles to permit MRI and a sustained drug-release profile. The biocompatibility, MR imaging properties and amonafide release kinetics of these microspheres were investigated during in vitro studies. A xenograft rodent model was used to demonstrate the feasibility to deliver these microspheres to liver tumors using hepatic transcatheter intra-arterial infusions and potential to visualize the intra-hepatic delivery of these microspheres to both liver tumor and normal tissues with MRI immediately after infusion. This approach offer the potential for catheter-directed drug delivery to liver tumors for reduced systemic toxicity and superior therapeutic outcomes.

  18. Evaluation of the Thermosensitive Release Properties of Microspheres Containing an Agrochemical Compound.

    Science.gov (United States)

    Terada, Takatoshi; Ohtsubo, Toshiro; Iwao, Yasunori; Noguchi, Shuji; Itai, Shigeru

    2017-01-01

    The purpose of this study was to develop a deeper understanding of the key physicochemical parameters involved in the release profiles of microsphere-encapsulated agrochemicals at different temperatures. Microspheres consisting of different polyurethanes (PUs) were prepared using our previously reported solventless microencapsulation technique. Notably, these microspheres exhibited considerable differences in their thermodynamic characteristics, including their glass transition temperature (Tg), extrapolated onset temperature (To) and extrapolated end temperature (Te). At test temperatures below the To of the PU, only 5-10% of the agrochemical was rapidly released from the microspheres within 1 d, and none was released thereafter. However, at test temperatures above the To of the PU, the rate of agrochemical release gradually increased with increasing temperatures, and the rate of release from the microspheres was dependent on the composition of the PU. Taken together, these results show that the release profiles of the microspheres were dependent on their thermodynamic characteristics and changes in their PU composition.

  19. Characterization of Fe3O4/P(St-MPEO) Amphiphilic Magnetic Polymer Microspheres

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Amphiphilic magnetic microspheres consisting of styrene and poly(ethylene oxide) macromonomer(MPEO) were prepared by dispersion copolymerization in the presence of Fe3O4 magnetic fluid in an ethanol/water medium. The sizes of the magnetic microspheres and their distribution were characterized by means of scanning electron microscopy(SEM). The surface morphology and the average surface roughness of the microspheres were investigated by virtue of atomic force microscopy(AFM). It was found that the microspheres exhibit microscopic phase-separate and the mean square surface roughness of the microspheres increases with increasing MPEO used in the copolymerization. The amphiphilic magnetic microspheres containing 0.4-3.5 mg/g hydroxyl groups could be prepared from MPEO with different concentrations and styrene.

  20. Mesoporous metal oxide microsphere electrode compositions and their methods of making

    Energy Technology Data Exchange (ETDEWEB)

    Paranthaman, Mariappan Parans; Liu, Hansan; Brown, Gilbert M.; Sun, Xiao-Guang; Bi, Zhonghe

    2016-12-06

    Compositions and methods of making are provided for mesoporous metal oxide microspheres electrodes. The mesoporous metal oxide microsphere compositions comprise (a) microspheres with an average diameter between 200 nanometers (nm) and 10 micrometers (.mu.m); (b) mesopores on the surface and interior of the microspheres, wherein the mesopores have an average diameter between 1 nm and 50 nm and the microspheres have a surface area between 50 m.sup.2/g and 500 m.sup.2/g. The methods of making comprise forming composite powders. The methods may also comprise refluxing the composite powders in a basic solution to form an etched powder, washing the etched powder with an acid to form a hydrated metal oxide, and heat-treating the hydrated metal oxide to form mesoporous metal oxide microspheres.

  1. Microspheres as carriers for lipase inhibitory substances to reduce dietary triglyceride absorption in mice

    Directory of Open Access Journals (Sweden)

    Shiuan-Huei Wu

    2016-01-01

    Full Text Available The present study intends to use microspheres as a delivery system of chlorogenic acid (CGA to investigate the influences of CGA microspheres on dietary fat absorption and fecal triglyceride excretion in a mice model. Microspheres have an average particle size of about 53.3 μm. Results indicated that the microspheres were capable of gradually releasing the preloaded CGA into the surrounding medium. Their bioadhesive property might help prolong the gastrointestinal transit time in mice, and render a better mixing and contact between CGA and triglyceride. Consumption of CGA microspheres resulted in a significantly higher level of fecal triglyceride (119–144% as compared with the corresponding control groups. A microsphere would be a desirable vehicle for CGA to improve its efficacy along the intestine.

  2. Use of spray-dried zirconia microspheres in the separation of immunoglobulins from cell culture supernatant.

    Science.gov (United States)

    Subramanian, A; Carr, P W; McNeff, C V

    2000-08-18

    A method suitable for the isolation of monoclonal antibodies (MAbs) on novel zirconia microspheres (20-30 microm) is described. Zirconia microspheres were generated by spray drying colloidal zirconia. Spray-dried zirconia microspheres were further classified and characterized by X-ray diffraction, BET porosimetry and scanning electron microscopy. Spray-dried zirconia microspheres were modified with ethylenediamine-N,N'-tetra(methylenephosphonic) acid (EDTPA) to create a cation-exchange chromatographic support. The chromatographic behavior of a semi-preparative column packed with EDTPA-modified zirconia microspheres was evaluated and implications for scale-up are provided. EDTPA-modified zirconia microspheres were further used to purify MAbs from cell culture supernatant. Analysis by enzyme linked immunosorbent assay and gel electrophoresis demonstrate that MAbs can be recovered from a cell culture supernatant at high yield (92-98%) and high purity (>95%) in a single chromatographic step.

  3. Aerogel microspheres from natural cellulose nanofibrils and their application as cell culture scaffold.

    Science.gov (United States)

    Cai, Hongli; Sharma, Sudhir; Liu, Wenying; Mu, Wei; Liu, Wei; Zhang, Xiaodan; Deng, Yulin

    2014-07-14

    We demonstrated that ultralight pure natural aerogel microspheres can be fabricated using cellulose nanofibrials (CNF) directly. Experimentally, the CNF aqueous gel droplets, produced by spraying and atomizing through a steel nozzle, were collected into liquid nitrogen for instant freezing followed by freeze-drying. The aerogel microspheres are highly porous with bulk density as low as 0.0018 g cm(-3). The pore size of the cellulose aeogel microspheres ranges from nano- to macrometers. The unique ultralight and high porous structure ensured high moisture (~90 g g(-1)) and water uptake capacity (~100 g g(-1)) of the aerogel microspheres. Covalent cross-linking between the native nanofibrils and cross-linkers made the aerogel microspheres very stable even in a harsh environment. The present study also confirmed this kind of aerogel microspheres from native cellulose fibers can be used as cell culture scaffold.

  4. Sub-wavelength image stitching with removable microsphere-embedded thin film

    Science.gov (United States)

    Du, Bintao; Ye, Yong-Hong; Hou, Jinglei; Guo, Minglei; Wang, Tian

    2016-01-01

    Imaging by dielectric microspheres embedded in thin film is a simple technique to achieve optical super-resolution. However, the film-thickness effect has not caused enough attention, and its field of view (FOV) is very limited. We first introduce a method to fabricate barium titanate glass (BTG) microsphere-embedded ultrathin polydimethylsiloxane (PDMS) films, and study their sub-wavelength imaging properties as a function of the film thickness. Our experimental results reveal that for an individual microsphere, its FOV obviously increases as the film thickness decreases, while the corresponding magnification changes barely. When the PDMS film thickness is 5-10 μm, the FOV of a microsphere is the largest, and the images produced by the neighboring close-packed microspheres with the same size can be stitched together to form a large image, realizing effective view expansion. Our results will boost the practical capacity of BTG microsphere-embedded film for sub-wavelength imaging.

  5. Raspberry-like PS/CdTe/Silica Microspheres for Fluorescent Superhydrophobic Materials

    Science.gov (United States)

    Chang, Jinghui; Zang, Linlin; Wang, Cheng; Sun, Liguo; Chang, Qing

    2016-02-01

    Superhydrophobic particulate films were fabricated via deposition of raspberry-like fluorescent PS/CdTe/silica microspheres on clean glass substrates and surface modification. Particularly, the fluorescent microspheres were prepared by a kind of modified strategy, namely introducing poly (acrylic acid)-functionalized polystyrene microspheres and thiol-stabilized CdTe quantum dots into a hydrolysis reaction of tetraethoxysilane simultaneously. And through adjusting the reaction parameters, the polystyrene spheres with two particle sizes and three colors of CdTe quantum dots aqueous solution were obtained. Consequently, raspberry-like microspheres consist of polystyrene cores and the composite shells of CdTe quantum dots and silica. These microspheres possess a fluorescent characteristic and form a hierarchical dual roughness which was conductive to superhydrophobicity, and the hydrophobic tests also showed the contact angles of water droplets on the surface of the raspberry-like microspheres which were over 160° at room temperature.

  6. Raspberry-like PS/CdTe/Silica Microspheres for Fluorescent Superhydrophobic Materials.

    Science.gov (United States)

    Chang, Jinghui; Zang, Linlin; Wang, Cheng; Sun, Liguo; Chang, Qing

    2016-12-01

    Superhydrophobic particulate films were fabricated via deposition of raspberry-like fluorescent PS/CdTe/silica microspheres on clean glass substrates and surface modification. Particularly, the fluorescent microspheres were prepared by a kind of modified strategy, namely introducing poly (acrylic acid)-functionalized polystyrene microspheres and thiol-stabilized CdTe quantum dots into a hydrolysis reaction of tetraethoxysilane simultaneously. And through adjusting the reaction parameters, the polystyrene spheres with two particle sizes and three colors of CdTe quantum dots aqueous solution were obtained. Consequently, raspberry-like microspheres consist of polystyrene cores and the composite shells of CdTe quantum dots and silica. These microspheres possess a fluorescent characteristic and form a hierarchical dual roughness which was conductive to superhydrophobicity, and the hydrophobic tests also showed the contact angles of water droplets on the surface of the raspberry-like microspheres which were over 160° at room temperature.

  7. Risperidone Attenuates Modified Stress-Re-stress Paradigm-Induced Mitochondrial Dysfunction and Apoptosis in Rats Exhibiting Post-traumatic Stress Disorder-Like Symptoms.

    Science.gov (United States)

    Garabadu, Debapriya; Ahmad, Ausaf; Krishnamurthy, Sairam

    2015-06-01

    Mitochondria play a significant role in the pathophysiology of post-traumatic stress disorder (PTSD). Risperidone and paroxetine were evaluated for their effect on mitochondrial dysfunction and mitochondria-dependent apoptosis in discrete brain regions in modified stress re-stress (SRS) animal model of PTSD. Male rats were subjected to stress protocol of 2 h restraint and 20 min forced swim followed by halothane anesthesia on day 2 (D-2). Thereafter, rats were exposed to re-stress (forced swim) on D-8 and at 6-day intervals on D-14, D-20, D-26, and D-32. The rats were treated with risperidone (0.01, 0.1, and 1.0 mg/kg p.o.) and paroxetine (10.0 mg/kg p.o.) from D-8 to D-32. Risperidone at median dose and paroxetine ameliorated modified SRS-induced depressive-like symptom (increase in immobility period) in forced swim, anxiety-like behavior (decrease in percentage of open arm entries and time spent) in elevated plus maze and cognitive deficits (loss in spatial recognition memory) in Y-maze tests on D-32. Risperidone, but not paroxetine, attenuated modified SRS-induced decreases in plasma corticosterone levels. Risperidone ameliorated increase in the activity of mitochondrial respiratory complex (I, II, IV, and V), decreases in the levels of mitochondrial membrane potential, cytochrome-C and caspase-9 in the hippocampus, hypothalamus, pre-frontal cortex, and amygdala. However, both drugs attenuated modified SRS-induced increase in the number of apoptotic cells and caspase-3 levels in all the brain regions indicating anti-apoptotic activity of these drugs. Hence, these results suggest that anti-apoptotic activity could be a common mechanism for anti-PTSD-like effect irrespective of the pathways of apoptosis in the modified SRS model.

  8. No change of dopamine transporter density in basal ganglia after risperidone treatment in drug-naive children with Tourette's disorder

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, W. K.; Ryu, Y. H.; Yoon, M. J.; Chun, K. A.; Lee, J. D. [College of Medicine, Univ. of Yonsei, Seoul (Korea, Republic of); Zee, D. Y. [Univ. of Inhwa, Incheon (Korea, Republic of); Choi, T. H. [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    2003-07-01

    Tourette's disorder (TD), which is characterized by multiple waxing and waning motor tics and one or more vocal tics, is known to be associated with abnormalities in the dopaminergic system. To testify our hypothesis that risperidone would improve tic symptoms of TD patients through the change of the dopaminergic system, we measured the DAT densities between drug-naive children with TD and normal children investigated the DAT density before and after treatment with risperidone in drug-naive children with TD, using lodine-123 labelled N-(3-iodopropen-2-yl)-2beta-carbomethoxy-3beta-(4-chlorophenyl) tropane(I-123 IPT) single photon emission computed tomography (SPECT). I-123 IPT SPECT imaging and Yale Global Tic Severity Scale-Korean version (YGTSS-K) for assessing the tic symptom severity were carried out before and after treatment with risperidone for 8 weeks in eight drug-naive children with TD. Eight normal children also underwent SPECT imaging 2 hours after an intravenous administration of I-123 IPT and carried out both quantitative and qualitative analyses using the obtained SPECT data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. The drug-naive children with TD had a significantly greater increase in the specific/nonspecific DAT binding ratio of both basal ganglia compared with the normal children. However, no significant difference in the specific/nonspecific DAT binding ratio of the basal ganglia before and after treatment with riperidone in children with TD was not found, although tic symptoms were significantly improved with risperidone. These findings suggest that DAT densities are directly associated with the pathophysiology of TD, however, that the effect of risperidone on tic symptoms in children with TD is not attributed to the change of dopaminergic system.

  9. Differences in frontal cortical activation by a working memory task after substitution of risperidone for typical antipsychotic drugs in patients with schizophrenia

    Science.gov (United States)

    Honey, Garry D.; Bullmore, Edward T.; Soni, William; Varatheesan, Malini; Williams, Steve C. R.; Sharma, Tonmoy

    1999-01-01

    Antipsychotic drug treatment of schizophrenia may be complicated by side effects of widespread dopaminergic antagonism, including exacerbation of negative and cognitive symptoms due to frontal cortical hypodopaminergia. Atypical antipsychotics have been shown to enhance frontal dopaminergic activity in animal models. We predicted that substitution of risperidone for typical antipsychotic drugs in the treatment of schizophrenia would be associated with enhanced functional activation of frontal cortex. We measured cerebral blood oxygenation changes during periodic performance of a verbal working memory task, using functional MRI, on two occasions (baseline and 6 weeks later) in two cohorts of schizophrenic patients. One cohort (n = 10) was treated with typical antipsychotic drugs throughout the study. Risperidone was substituted for typical antipsychotics after baseline assessment in the second cohort (n = 10). A matched group of healthy volunteers (n = 10) was also studied on a single occasion. A network comprising bilateral dorsolateral prefrontal and lateral premotor cortex, the supplementary motor area, and posterior parietal cortex was activated by working memory task performance in both the patients and comparison subjects. A two-way analysis of covariance was used to estimate the effect of substituting risperidone for typical antipsychotics on power of functional response in the patient group. Substitution of risperidone increased functional activation in right prefrontal cortex, supplementary motor area, and posterior parietal cortex at both voxel and regional levels of analysis. This study provides direct evidence for significantly enhanced frontal function in schizophrenic patients after substitution of risperidone for typical antipsychotic drugs, and it indicates the potential value of functional MRI as a tool for longitudinal assessment of psychopharmacological effects on cerebral physiology. PMID:10557338

  10. Preparation and characterization of monodisperse large-porous silica microspheres as the matrix for protein separation.

    Science.gov (United States)

    Xia, Hongjun; Wan, Guangping; Zhao, Junlong; Liu, Jiawei; Bai, Quan

    2016-11-04

    High performance liquid chromatography (HPLC) is a kind of efficient separation technology and has been used widely in many fields. Micro-sized porous silica microspheres as the most popular matrix have been used for fast separation and analysis in HPLC. In this paper, the monodisperse large-porous silica microspheres with controllable size and structure were successfully synthesized with polymer microspheres as the templates and characterized. First, the poly(glycidyl methacrylate-co-ethyleneglycol dimethacrylate) microspheres (PGMA-EDMA) were functionalized with tetraethylenepentamine (TEPA) to generate amino groups which act as a catalyst in hydrolysis of tetraethyl orthosilicate (TEOS) to form Si-containing low molecular weight species. Then the low molecular weight species diffused into the functionalized PGMA-EDMA microspheres by induction force of the amino groups to form polymer/silica hybrid microspheres. Finally, the organic polymer templates were removed by calcination, and the large-porous silica microspheres were obtained. The compositions, morphology, size distribution, specific surface area and pore size distribution of the porous silica microspheres were characterized by infrared analyzer, scanning-electron microscopy, dynamic laser scattering, the mercury intrusion method and thermal gravimetric analysis, respectively. The results show that the agglomeration of the hybrid microspheres can be overcome when the templates were functionalized with TEPA as amination reagent, and the yield of 95.7% of the monodisperse large-porous silica microspheres can be achieved with high concentration of polymer templates. The resulting large-porous silica microspheres were modified with octadecyltrichlorosilane (ODS) and the chromatographic evaluation was performed by separating the proteins and the digest of BSA. The baseline separation of seven kinds of protein standards was achieved, and the column delivered a better performance when separating BSA digests

  11. Fabrication of uranium dioxide ceramic pellets with controlled porosity from oxide microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Remy, E. [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Picart, S., E-mail: sebastien.picart@cea.fr [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Delahaye, T. [Fuel Cycle Technology Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Jobelin, I. [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Dugne, O. [Fuel Cycle Technology Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Bisel, I. [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Blanchart, P. [Heterogeneous Materials Research Group, Centre Européen de la Céramique, F-87068 Limoges (France); Ayral, A. [Institut Européen des Membranes, UMR 5635 CNRS-ENSCM-UM2, University of Montpellier, F-34095 Montpellier cedex 5 (France)

    2014-05-01

    This study concerns the fabrication of uranium oxide pellets using the powder-free process called Calcined Resin Microsphere Pelletization (CRMP). Details are given about oxide microsphere synthesis and particularly about loading operation and heat treatments. The fabrication of ceramic pellets is also described and discussed. Results showed that this process allows the preparation of either dense or porous pellets by mixing U{sub 3}O{sub 8} and UO{sub 2}-like microspheres before pressing and sintering.

  12. A general approach to mesoporous metal oxide microspheres loaded with noble metal nanoparticles

    KAUST Repository

    Jin, Zhao

    2012-04-26

    Catalytic microspheres: A general approach is demonstrated for the facile preparation of mesoporous metal oxide microspheres loaded with noble metal nanoparticles (see TEM image in the picture). Among 18 oxide/noble metal catalysts, TiO 2/0.1 mol Pd microspheres showed the highest turnover frequency in NaBH 4 reduction of 4-nitrophenol (see picture). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Raspberry-like PS/CdTe/Silica Microspheres for Fluorescent Superhydrophobic Materials

    OpenAIRE

    Chang, Jinghui; Zang, Linlin; Wang, Cheng; Sun, Liguo; Chang, Qing

    2016-01-01

    Superhydrophobic particulate films were fabricated via deposition of raspberry-like fluorescent PS/CdTe/silica microspheres on clean glass substrates and surface modification. Particularly, the fluorescent microspheres were prepared by a kind of modified strategy, namely introducing poly (acrylic acid)-functionalized polystyrene microspheres and thiol-stabilized CdTe quantum dots into a hydrolysis reaction of tetraethoxysilane simultaneously. And through adjusting the reaction parameters, the...

  14. Validation of large-scale, monochromatic UV disinfection systems for drinking water using dyed microspheres.

    Science.gov (United States)

    Blatchley, E R; Shen, C; Scheible, O K; Robinson, J P; Ragheb, K; Bergstrom, D E; Rokjer, D

    2008-02-01

    Dyed microspheres have been developed as a new method for validation of ultraviolet (UV) reactor systems. When properly applied, dyed microspheres allow measurement of the UV dose distribution delivered by a photochemical reactor for a given operating condition. Prior to this research, dyed microspheres had only been applied to a bench-scale UV reactor. The goal of this research was to extend the application of dyed microspheres to large-scale reactors. Dyed microsphere tests were conducted on two prototype large-scale UV reactors at the UV Validation and Research Center of New York (UV Center) in Johnstown, NY. All microsphere tests were conducted under conditions that had been used previously in biodosimetry experiments involving two challenge bacteriophage: MS2 and Qbeta. Numerical simulations based on computational fluid dynamics and irradiance field modeling were also performed for the same set of operating conditions used in the microspheres assays. Microsphere tests on the first reactor illustrated difficulties in sample collection and discrimination of microspheres against ambient particles. Changes in sample collection and work-up were implemented in tests conducted on the second reactor that allowed for improvements in microsphere capture and discrimination against the background. Under these conditions, estimates of the UV dose distribution from the microspheres assay were consistent with numerical simulations and the results of biodosimetry, using both challenge organisms. The combined application of dyed microspheres, biodosimetry, and numerical simulation offers the potential to provide a more in-depth description of reactor performance than any of these methods individually, or in combination. This approach also has the potential to substantially reduce uncertainties in reactor validation, thereby leading to better understanding of reactor performance, improvements in reactor design, and decreases in reactor capital and operating costs.

  15. Microwave Irradiation Assisted Preparation of Chitosan Composite Microsphere for Dye Adsorption

    OpenAIRE

    Xiaoyu Chen; Lindun He

    2017-01-01

    Chitosan-activated carbon composite microspheres were prepared by emulsion cross-linking method and its adsorption properties for methyl orange were studied. Chitosan solution was mixed with activated carbon powder and then chitosan was cross-linked by epichlorohydrin under microwave irradiation. SEM photos show that the composite microspheres have diameters of 200–400 μm and activated carbon powder dispersed on the surface of composite microsphere. FTIR spectrum indicates chitosan is success...

  16. POE-PEG-POE triblock copolymeric microspheres containing protein. I. Preparation and characterization.

    Science.gov (United States)

    Yang, Y Y; Wan, J P; Chung, T S; Pallathadka, P K; Ng, S; Heller, J

    2001-07-10

    Poly(ortho ester) (POE)-poly (ethylene glycol) (PEG) triblock copolymers (POE-PEG-POE) with different PEG contents were synthesised as carriers for controlled protein delivery. POE-PEG-POE microspheres containing bovine serum albumin (BSA) were prepared using a double-emulsion (water-in-oil-in-water) process. In this first paper of a two-part series, we report the fundamentals of the fabrication and characterization of POE-PEG-POE microspheres. Because the triblock copolymer is more hydrophilic than neat poly(ortho ester), the triblock copolymer yields a more stable first emulsion (water-in-oil) and a greater BSA encapsulation efficiency (90% vs. 30%). No BSA is found on POE-PEG-POE microsphere surfaces measured by X-ray photoelectron spectroscopy, while uniform BSA distributions are observed within the microspheres by confocal microscopy. SEM pictures show that an increase in PEG content results in microspheres with a denser cross-section because of a more stable first emulsion and better affinity between the copolymer and water. POE-PEG(20%)-POE suffers significant swelling during the fabrication process and yields the biggest microspheres. However, the POE-PEG(30%)-POE microspheres are much smaller since the dissolution loss of POE-PEG(30%)-POE in the external water phase may be much higher than that of POE-PEG(20%)-POE. The salt concentration in the external water phase significantly affects the morphology of the resultant microspheres. Microspheres with a dense wall are produced when using pure water as the external water phase. Polymer concentration has less impact on BSA encapsulation efficiency but has a considerable effect on microsphere size and morphology. Increasing the concentration of the polyvinyl alcohol emulsifier does not cause an obvious decrease in microsphere size. However, increased BSA loading results in bigger microspheres.

  17. Design and evaluation of controlled release mucoadhesive microspheres of amoxicillin for anti Helicobacter pylori therapy

    OpenAIRE

    N Venkateswaramurthy; Sambathkumar, R.; Perumal, P.

    2011-01-01

    The aim of this study was to develop controlled release mucoadhesive microspheres of amoxicillin trihydrate for the treatment of peptic ulcer disease caused by Helicobacter pylori (H. pylori). Microspheres were prepared by solvent evaporation technique using carbopol 974P, hydroxypropyl methyl cellulose K4M (HPMC K4M) and Eudragit RS 100. The prepared microspheres were subjected to evaluation for particle size, incorporation efficiency, in vitro mucoadhesion and in vitro drug release characte...

  18. Polystyrene microsphere-based lanthanide luminescent chemosensor for detection of organophosphate pesticides

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hongxing; HUA Xiufu; TUO Xinlin; CHEN Chuanzhi; WANG Xiaogong

    2012-01-01

    Fluorescent microspheres of polystyrene-based Eu(Ⅲ) complexes were prepared from TentaGel resin,2,6-bisbenzimidazolylpyridine and europium nitrate.The microspheres were characterized by FTIR spectroscopy,elemental analysis,XPS measurements and fluorescence spectroscopy.Characteristic red emission under irradiation of 365 nm light from a hand-held UV lamp was observed for the microspheres either in a solution or solid-state.Fluorescent quenching was observed when the microspheres were exposed to a trace amount of diethyl chlorophosphate (DCP) in the dispersion.The material and property can be potentially used to fabricate chemosensor in the detection of organophosphates.

  19. Template-flee approach for hydrothermal fabrication of ZnO microspheres

    Institute of Scientific and Technical Information of China (English)

    Hao Jiang; Junqing Hu; Feng Gu; Chunzhong Li

    2009-01-01

    Wurtzite ZnO microspheres, 5.5-11 μm in diameter and with smooth surfaces, were prepared in abso-lute ethanol via a simple template-free method in the presence of ethylenediamine. The products were characterized using X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy. This simple method to fabricate ZnO microspheres shows high yield (>90%) and good repro-ducibility. The formation process of ZnO microspheres was discussed. The as-obtained ZnO microspheres are expected to provide some immediate advantages for optical, microelectronic, and biological applica-tions.

  20. Study on Magnetic Responsibility of Rare Earth Ferrite/Polyacrylamide Magnetic Microsphere

    Institute of Scientific and Technical Information of China (English)

    Zhang Ming; Wang Zhifeng; Zhang Hong; Dai Shaojun; Qiu Guanming; Okamoto Hiroshi

    2005-01-01

    In inverse microemulsion, rare earth ferrite/polyacrylamide magnetic microsphere were prepared and their magnetic responsibility were studied by magnetic balance. Results indicate that the magnetic responsibility of microsphere relates to magnetic moment of rare earth ion, and it can be improved by the addition of dysprosium ion of high magnetic moment. Dysprosium content has an effect on magnetic responsibility of dysprosium ferrite/polyacrylamide magnetic microsphere. The microsphere displays strong magnetic responsibility when the molar ratio of Dy3+/iron is 0.20.

  1. Bioassay and biomolecular identification, sorting, and collection methods using magnetic microspheres

    Science.gov (United States)

    Kraus, Jr., Robert H.; Zhou, Feng; Nolan, John P

    2007-06-19

    The present invention is directed to processes of separating, analyzing and/or collecting selected species within a target sample by use of magnetic microspheres including magnetic particles, the magnetic microspheres adapted for attachment to a receptor agent that can subsequently bind to selected species within the target sample. The magnetic microspheres can be sorted into a number of distinct populations, each population with a specific range of magnetic moments and different receptor agents can be attached to each distinct population of magnetic microsphere.

  2. Synthesis of TiO2/Poly(styrene-co-divinybenzene)Nanocomposite Microspheres by Grafting Copolymerization

    Institute of Scientific and Technical Information of China (English)

    LI Sen; WANG Kuan; CHENG Jiang; WEN Xiu-Fang; PI Pi-Hui; YANG Zhuo-Ru; LI Zhi-Ying

    2008-01-01

    Porous and nonporous nanocomposite microspheres were successfully prepared by grafting titania (TiO2) particles to poly(styrene-co-divinylbenzene) microsphere involving silane coupling agent 3-glycidoxypropyltri-methoxysilane (KH560), styrene and maleic anhydride as coupling agents. The effects of KH560 and styrene on the dispersion and amount of grafted-titania on the surface of the microsphere (nonporous) as well as the effect of porous properly of the supporting microsphere on the amount of grafted-TiO2 within the microsphere (porous) were investigated. The results indicated that both KH560 and styrene could enhance the stability and dispersion of TiO2 particles attached to the surface of the microsphere producing grain size with diameter in the range of 30-80 nm. With nonporous microsphere styrene also increased the amount of grafted-TiO2 particles on the microsphere from 10.4% to 20.4% as revealed by TGA. Porous nanoeomposite microspheres with mean pore size of 136 nm could accommodate more TiO2 particles larger than either nonporous nanocomposite or porous nancomposite with mean pore size of 31 nm, yielding maximum of 26% by weight of grafted-TiO2.

  3. In vitro and in vivo evaluation of drug-eluting microspheres designed for transarterial chemoembolization therapy.

    Science.gov (United States)

    Wang, Yujing; Molin, Daniël G M; Sevrin, Chantal; Grandfils, Christian; van den Akker, Nynke M S; Gagliardi, Mick; Knetsch, Menno L; Delhaas, Tammo; Koole, Leo H

    2016-04-30

    Poly(D,L-lactic acid) biodegradable microspheres, loaded with the drugs cisplatin and/or sorafenib tosylate, were prepared, characterized and studied. Degradation of the microspheres, and release of cisplatin and/or sorafenib tosylate from them, were investigated in detail. Incubation of the drug-carrying microspheres in phosphate buffered saline (pH=7.4) revealed slow degradation. Nevertheless, significant release of cisplatin and sorafenib tosylate from microspheres loaded with both drugs was apparent in vitro; this can be attributed to their porous structure. Supernatants from microspheres loaded with both drugs showed strong toxic effects on cells (i.e. endothelial cells, fibroblast cells and Renca tumor cells) and potent anti-angiogenic effect in the matrigel endothelial tube assay. In vivo anti-tumor effects of the microspheres were also observed, in a Renca tumor mouse model. The poly(D,L-lactic acid) microspheres containing both cisplatin and sorafenib tosylate revealed highest therapeutic efficacy, probably demonstrating that combined local administration of cisplatin and sorafenib tosylate synergistically inhibits tumor growth in situ. In conclusion, this study demonstrates the applicability of biodegradable poly(D,L-lactic acid) microspheres loaded with cisplatin and sorafenib tosylate for local drug delivery as well as the potential of these microspheres for future use in transarterial chemoembolization.

  4. A review of recent progress in preparation of hollow polymer microspheres

    Institute of Scientific and Technical Information of China (English)

    Wei Bin; Wang Shujun; Song Hongguang; Liu Hongyan; Li Jie; Liu Ning

    2009-01-01

    The preparation methods of hollow polymer microspheres both at home and abroad are summarized, and their preparation mechanisms and developmental states are presented. These methods include the liquid droplet method, dried-gel droplet method, self-assembly method, microencapsulation method, emulsion polymerization method and the template method. Hollow polystyrene microspheres are the most extensively studied in the research of hollow polymer microspheres. Through comparison of the advantages and disadvantages of different preparation methods, it is concluded that microencapsulation method is most suitable for preparing polystyrene hollow microspheres.

  5. Facile preparation of multifunctional superparamagnetic PHBV microspheres containing SPIONs for biomedical applications

    Science.gov (United States)

    Li, Wei; Jan Zaloga; Ding, Yaping; Liu, Yufang; Janko, Christina; Pischetsrieder, Monika; Alexiou, Christoph; Boccaccini, Aldo R.

    2016-03-01

    The promising potential of magnetic polymer microspheres in various biomedical applications has been frequently reported. However, the surface hydrophilicity of superparamagnetic iron oxide nanoparticles (SPIONs) usually leads to poor or even failed encapsulation of SPIONs in hydrophobic polymer microspheres using the emulsion method. In this study, the stability of SPIONs in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) solution was significantly increased after surface modification with lauric acid. As a result, magnetic PHBV microspheres with high encapsulation efficiencies (71.0-87.4%) were prepared using emulsion-solvent extraction/evaporation method. Magnetic resonance imaging (MRI) showed significant contrast for the magnetic PHBV microspheres. The toxicity of these magnetic PHBV microspheres towards human T-lymphoma suspension cells and adherent colon carcinoma HT-29 cells was investigated using flow cytometry, and they were shown to be non-toxic in a broad concentration range. A model drug, tetracycline hydrochloride, was used to demonstrate the drug delivery capability and to investigate the drug release behavior of the magnetic PHBV microspheres. The drug was successfully loaded into the microspheres using lauric acid-coated SPIONs as drug carrier, and was released from the microspheres in a diffusion controlled manner. The developed magnetic PHBV microspheres are promising candidates for biomedical applications such as targeted drug delivery and MRI.

  6. Synthesis and characterization of magnesium gluconate contained poly(lactic-co-glycolic acid)/chitosan microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Shekh M. [Department of Chemical, Biological and Bioengineering, North Carolina A& T State University, 1601 East Market Street, Greensboro, NC 27411 (United States); NSF Engineering Research Center for Revolutionizing Metallic Biomaterials, North Carolina A& T State University, Greensboro, NC 27411 (United States); Mahoney, Christopher [Department of Bioengineering, University of Pittsburgh, 4200 Fifth Avenue, Pittsburgh, PA 15250 (United States); Sankar, Jagannathan [NSF Engineering Research Center for Revolutionizing Metallic Biomaterials, North Carolina A& T State University, Greensboro, NC 27411 (United States); Department of Mechanical Engineering, North Carolina A& T State University, 1601 East Market Street, Greensboro, NC 27411 (United States); Marra, Kacey G. [NSF Engineering Research Center for Revolutionizing Metallic Biomaterials, North Carolina A& T State University, Greensboro, NC 27411 (United States); Department of Bioengineering, University of Pittsburgh, 4200 Fifth Avenue, Pittsburgh, PA 15250 (United States); Department of Plastic Surgery, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 15250 (United States); McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive, Pittsburgh, PA 15250 (United States); Bhattarai, Narayan, E-mail: nbhattar@ncat.edu [Department of Chemical, Biological and Bioengineering, North Carolina A& T State University, 1601 East Market Street, Greensboro, NC 27411 (United States); NSF Engineering Research Center for Revolutionizing Metallic Biomaterials, North Carolina A& T State University, Greensboro, NC 27411 (United States)

    2016-01-15

    Graphical abstract: - Highlights: • Magnesium gluconate contained PLGA/chitosan microspheres were fabricated. • In vitro release of magnesium ions was performed using Xylidyl Blue assay. • Chitosan coated PLGA can significantly control the release of magnesium ions. • Cellular compatibility was tested using adipose-derived stem cells and PC12 cells. • The cells encounter acceptably low levels of damage in contact with microspheres. - Abstract: The goal of this study was to fabricate and investigate the chitosan coated poly(lactic-co-glycolic acid) (PLGA) microspheres for the development of controlled release magnesium delivery system. PLGA based microspheres are ideal vehicles for many controlled release drug delivery applications. Chitosan is a naturally occurring biodegradable and biocompatible polysaccharide, which can coat the surface of PLGA to alter the release of drugs. Magnesium gluconate (MgG) was encapsulated in the PLGA and PLGA/chitosan microspheres by utilizing the double emulsion solvent evaporation technique for controlled release study. The microspheres were tested with respect to several physicochemical and biological properties, including morphology, chemical structure, chitosan adsorption efficiency, magnesium encapsulation efficiency, in vitro release of magnesium ions, and cellular compatibility using both human adipose-derived stem cells (ASCs) and PC12 cells. Chitosan coated PLGA microspheres can significantly control the release of magnesium ions compared to uncoated PLGA microspheres. Both coated and uncoated microspheres showed good cellular compatibility.

  7. Preparation, characterization, and in vitro release of gentamicin from coralline hydroxyapatite-alginate composite microspheres.

    Science.gov (United States)

    Sivakumar, M; Rao, K Panduranga

    2003-05-01

    In this work, composite microspheres were prepared from bioactive ceramics such as coralline hydroxyapatite [Ca(10)(PO(4))(6)(OH)(2)] granules, a biodegradable polymer, sodium alginate, and an antibiotic, gentamicin. Previously, we have shown a gentamicin release from coralline hydroxyapatite granules-chitosan composite microspheres. In the present investigation, we attempted to prepare composite microspheres containing coralline hydroxyapatite granules and sodium alginate by the dispersion polymerization technique with gentamicin incorporated by absorption method. The crystal structure of the composite microspheres was analyzed using X-ray powder diffractometer. Fourier transform infrared spectra clearly indicated the presence of per-acid of sodium alginate, phosphate, and hydroxyl groups in the composite microspheres. Scanning electron micrographs and optical micrographs showed that the composite microspheres were spherical in shape and porous in nature. The particle size of composite microspheres was analyzed, and the average size was found to be 15 microns. The thermal behavior of composite microspheres was studied using thermogravimetric analysis and differential scanning calorimetric analysis. The cumulative in vitro release profile of gentamicin from composite microspheres showed near zero order patterns.

  8. The Pharmacokinetics and Pharmacodynamics of Lidocaine- Loaded Biodegradable Poly(lactic-co-glycolic acid) Microspheres

    OpenAIRE

    Jianming Liu; Xin Lv

    2014-01-01

    The purpose of this study was to develop novel lidocaine microspheres. Microspheres were prepared by the oil-in-water (o/w) emulsion technique using poly(d,l-lactide-co-glycolide acid) (PLGA) for the controlled delivery of lidocaine. The average diameter of lidocaine PLGA microspheres was 2.34 ± 0.3 μm. The poly disperse index was 0.21 ± 0.03, and the zeta potential was +0.34 ± 0.02 mV. The encapsulation efficiency and drug loading of the prepared microspheres were 90.5% ± 4.3% and 11.2% ± 1...

  9. FORMULATION AND EVALUATION OF MUCOADHESIVE MICROSPHERES OF PIOGLITAZONE HYDROCHLORIDE USING A NATURAL POLYMER

    Directory of Open Access Journals (Sweden)

    Mobeen Mohd.

    2015-04-01

    Full Text Available The objective of the present investigation was to design a controlled release dosage form for a thiazolidinedione oral hypoglycemic drug i.e., pioglitazone hydrochloride employing a natural polymer. The present study was also aimed to increase the biological half-life by developing it in the form of sustained release microspheres. The present study aimed at employing a natural polymer in formulating the mucoadhesive microspheres and estimate its effect over the controlled release of the drug from the formulation. The microspheres of pioglitazone hydrochloride were prepared by employing sodium alginate as a cell forming polymer and by using a natural bio-adhesive polymer viz. goru gum in the ratios of 1:1, 1:1.5 and 1:2, by orifice ion gelation method with varying concentrations of calcium chloride. Six batches of microspheres (MS1 – MS6 were prepared. The microspheres were evaluated for various micromeritic properties and it was observed that all the batches exhibited free-flowing properties. Scanning electron microscopy results showed that the microspheres were almost spherical in shape and discrete. The FTIR results showed that there were no interactions between the drug and the excipients. The in vitro release profile indicated that all the batches of microspheres showed controlled and prolonged drug release over an extended period, with acceptable release kinetics. The work demonstrated that among all the formulations of microspheres, the microspheres of the formulation MS4 are promising candidates for the sustained release of pioglitazone hydrochloride.

  10. Synthesis of Core-Shell @@ Microspheres and Their Application as Recyclable Photocatalysts

    Directory of Open Access Journals (Sweden)

    Zhenghua Wang

    2012-01-01

    Full Text Available We report the fabrication of core-shell Fe3O4@SiO2@TiO2 microspheres through a wet-chemical approach. The Fe3O4@SiO2@TiO2 microspheres possess both ferromagnetic and photocatalytic properties. The TiO2 nanoparticles on the surfaces of microspheres can degrade organic dyes under the illumination of UV light. Furthermore, the microspheres are easily separated from the solution after the photocatalytic process due to the ferromagnetic Fe3O4 core. The photocatalysts can be recycled for further use with slightly lower photocatalytic efficiency.

  11. Synthesis of Core-Shell @ @ Microspheres and Their Application as Recyclable Photocatalysts

    OpenAIRE

    Zhenghua Wang; Ling Shen; Shiyu Zhu

    2012-01-01

    We report the fabrication of core-shell Fe3O4@SiO2@TiO2 microspheres through a wet-chemical approach. The Fe3O4@SiO2@TiO2 microspheres possess both ferromagnetic and photocatalytic properties. The TiO2 nanoparticles on the surfaces of microspheres can degrade organic dyes under the illumination of UV light. Furthermore, the microspheres are easily separated from the solution after the photocatalytic process due to the ferromagnetic Fe3O4 core. The photocatalysts can be recycled for further us...

  12. Preparation of PLLA/bpV(pic) microspheres and their effect on nerve cells.

    Science.gov (United States)

    Lin, Qiang; Chen, Hai-yun; Li, Hao-shen; Cai, Yang-ting

    2014-02-01

    In this study, we prepared PLLA/bpV(pic) microspheres, a bpV(pic) controlled release system and examined their ability to protect nerve cells and promote axonal growth. PLLA microspheres were prepared by employing the o/w single emulsification-evaporation technique. Neural stem cells and dorsal root ganglia were divided into 3 groups in terms of the treatment they received: a routine medium group (cultured in DMEM), a PLLA microsphere group (DMEM containing PLLA microspheres alone) and a PLLA/bpV(pic) group [DMEM containing PLLA/bpV(pic) microspheres]. The effects of PLLA/bpV(pic) microspheres were evaluated by the live-dead test and measurement of axonal length. Our results showed that PLLA/bpV(pic) granulation rate was (88.2±5.6)%; particle size was (16.8±3.1)%, drug loading was (4.05±0.3)%; encapsulation efficiency was (48.5±1.8)%. The release time lasted for 30 days. In PLLA/bpV(pic) microsphere group, the cell survival rate was (95.2 ±4.77)%, and the length of dorsal root ganglion (DRG) was 718±95 μm, which were all significantly greater than those in ordinary routine medium group and PLLA microsphere group. This preliminary test results showed the PLLA/bpV(pic) microspheres were successfully prepared and they could promote the survival and growth of neural cells in DRG.

  13. INVESTIGATION OF DRUG RELEASE FROM BIODEGRADABLE PLG MICROSPHERES: EXPERIMENT AND THEORY

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS, MALCOLM J. [Los Alamos National Laboratory; BERCHANE, NADER S. [Los Alamos National Laboratory; CARSON, KENNETH H. [Los Alamos National Laboratory; RICE-FICHT, ALLISON C. [Los Alamos National Laboratory

    2007-01-30

    Piroxicam containing PLG microspheres having different size distributions were fabricated, and in vitro release kinetics were determined for each preparation. Based on the experimental results, a suitable mathematical theory has been developed that incorporates the effect of microsphere size distribution and polymer degradation on drug release. We show from in vitro release experiments that microsphere size has a significant effect on drug release rate. The initial release rate decreased with an increase in microsphere size. In addition, the release profile changed from first order to concave-upward (sigmoidal) as the system size was increased. The mathematical model gave a good fit to the experimental release data.

  14. Post-facelift flap necrosis treatment using charged polystyrene microspheres

    Science.gov (United States)

    Weissman, Oren; Farber, Nimrod; Remer, Eric; Tessone, Ariel; Trivizki, Omer; Bank, Jonathan; Winkler, Eyal; Zilinsky, Isaac; Haik, Josef

    2013-01-01

    BACKGROUND: Flap necrosis following facial rhytidectomy constitutes a vexing and grievous complication to the patient and the surgeon. Treatment modalities that can expedite wound healing and re-epithelialization rates are highly desired. OBJECTIVES: To assess wound healing and re-epithelialization rates of open wounds following postrhytidectomy flap necrosis treated with commercially available charged polystyrene microspheres (Polyheal-1, Polyheal Ltd, Israel). METHODS: Flap necrosis following rhytidectomy with open wounds in three female patients were treated using dressings soaked with Polyheal-1. Wound closure rates were documented. RESULTS: The wounds demonstrated both accelerated granulation tissue formation and rapid re-epithelialization rates. No complications or side effects were encountered. CONCLUSIONS: Charged polystyrene microspheres may offer a new and efficacious way to treat open wounds due to flap necrosis following facial rhytidectomy. Further research with larger patient numbers is still needed to verify these findings. PMID:24431937

  15. L-Cysteine-assisted Synthesis of Copper Gallium Sulfide Microspheres

    Institute of Scientific and Technical Information of China (English)

    LIANG Xiao-juan; ZHONG Jia-song; CAI Qian; HUANG Hai-yu; LIU Hai-tao; XIANG Wei-dong; SUN Jun-cai

    2012-01-01

    An effective L-cysteine-assisted synthetic route has been successfully developed to prepare copper gallium sulfide(CuGaS2) microspheres under solvothermal conditions with CuCI2-2H2O,GaCl3 and L-cysteine as source materials,in which L-cysteine was used as the sulfide source and eomplexing molecule.The experiments revealed that the synthesized sample was of a typical CuGaS2 tetragonal structure.Moreover,the prepared CuGaS2 crystals consisting of microspheres made up of nanoflakes,and the diameter of the nanoflakes was about 20 nm.Raman spectrum of the obtained CuGaS2 exhibits a high-intensity peak of the A1 mode at 306 cm-1.Meanwhile,a possible growth mechanism was proposed based on the investigations.

  16. Synthesis and characterization of porous microspheres bearing pyrrolidone units

    Energy Technology Data Exchange (ETDEWEB)

    Maciejewska, M., E-mail: mmacieje@umcs.pl; Kołodyńska, D.

    2015-01-15

    Porous microspheres of glycydyl methacrylate (GMA) cross-linked with trimethylolpropane trimethacrylate (TRIM) were prepared with toluene as porogen by suspension-emulsion polymerization. With increasing molar ratio of the functional monomer to cross-linker, the epoxy group content increases significantly whereas the parameters of porous structure (specific surface area and total pore volume) decreases. In order to obtain adsorbents bearing functional groups the porous methacrylate network was modified by subsequent reaction with pyrrolidone. The materials were studied using elemental analysis, infrared spectroscopy, atomic force microscopy (AFM), attenuated total reflection (ATR) spectroscopy, Raman spectroscopy, thermal gravimetry. Additionally, polymers sorption capacity towards Cu(II) was investigated. - Highlights: • Porous microspheres with reactive epoxy group were synthesized. • Highly developed porous structure was created. • Pyrrolidone units were incorporated during ring–opening reaction. • Polymers sorption capacity towards Cu (II) was investigated.

  17. Preparation of polystyrene microspheres for laser velocimetry in wind tunnels

    Science.gov (United States)

    Nichols, Cecil E., Jr.

    1987-01-01

    Laser Velocimetry (L/V) had made great strides in replacing intrusive devices for wind tunnel flow measurements. The weakness of the L/V has not been the L/V itself, but proper size seeding particles having known drag characteristics. For many Langley Wind Tunnel applications commercial polystyrene latex microspheres suspended in ethanol, injected through a fluid nozzle provides excellent seeding but was not used due to the high cost. This paper provides the instructions, procedures, and formulations for producing polystyrene latex monodisperse microspheres of 0.6, 1.0, 1.7, 2.0, and 2.7 micron diameters. These are presently being used at Langley Research Center as L/V seeding particles.

  18. Polyacrylate microspheres composite for all-solid-state reference electrodes.

    Science.gov (United States)

    Kisiel, Anna; Donten, Mikołaj; Mieczkowski, Józef; Rius-Ruiz, F Xavier; Maksymiuk, Krzysztof; Michalska, Agata

    2010-09-01

    A novel concept is proposed for the encapsulation of components within polyacrylate microspheres, prior to their incorporation into a membrane phase. Thus finer and better controlled dispersion of heterogeneous membrane components can be achieved. This concept was verified by using a poly(n-butyl acrylate) membrane-based reference electrode as an example. In this example the proper dispersion of solid constituents of the heterogeneous membrane and prevention of their leakage are both of primary importance. Potassium chloride-loaded poly(n-butyl acrylate) microspheres were prepared and then left in contact with silver nitrate to convert some of the KCl into AgCl. The material obtained was introduced into a poly(n-butyl acrylate) membrane. The reference electrode membranes obtained in this way were characterized with much more stable potential (both in different electrolytes and over time) compared with electrodes prepared by the direct introduction of KCl and AgCl to the membrane.

  19. Stimuli-responsive polyaniline coated silica microspheres and their electrorheology

    Science.gov (United States)

    Park, Dae Eun; Choi, Hyoung Jin; Vu, Cuong Manh

    2016-05-01

    Silica/polyaniline (PANI) core-shell structured microspheres were synthesized by coating the surface of silica micro-beads with PANI and applied as a candidate inorganic/polymer composite electrorheological (ER) material. The silica micro-beads were initially modified using N-[(3-trimethoxysilyl)-propyl] aniline to activate an aniline functional group on the silica surface for a better PANI coating. The morphology of the PANI coating on the silica surface was examined by scanning electron microscopy and the silica/PANI core-shell structure was confirmed by transmission electron microscopy. The chemical structure of the particles was confirmed by Fourier transform infrared spectroscopy. Rotational rheometry was performed to confirm the difference in the ER properties between pure silica and silica/PANI microsphere-based ER fluids when dispersed in silicone oil.

  20. PREPARATION AND EVALUATION OF, NORETHISTERONE/POLY D, L-LACTIDE-CO-GLYCOLIDE MICROSPHERES IN VITRO AND IN VIVO

    Institute of Scientific and Technical Information of China (English)

    ZHOUZhi-Fang; ZHOUMing-Xing; SHENZheng-Rong; SHENWen-Zhao

    1989-01-01

    Biodegradable poly d, l-lactide 90-co-glycolide 10 was used to prepare microspheres containing 20% NET by solvent evaporation method. The drug content and morphology of the prepared microspheres were affected by the initial PLGA concentration in