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1.
Pharmazie ; 74(6): 326-333, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31138368

RESUMO

Objective: Formulations containing probiotics are promoted due to health benefits. During lyophilization and subsequent storage in the gastrointestinal tract, bacteria are exposed to stress conditions that can lead to impairment and loss of viability. Methods: The suitability of various excipients for enhancing the stability and functionality of Bifidobacterium longum subsp. infantis during storage as freeze-dried powder and through exposure to acid and bile was investigated. Cells were lyophilized in the presence of sucrose, trehalose, lactose, cellobiose and fructooligosaccharide (FOS) and stored at 4 °C or 25 °C. The effect of diverse protectants on the persistence after exposure to acid and bile environment was examined through determination of the colony forming units, the ß-glucosidase and ß-galactosidase activity and the membrane integrity changes. Results: Cells freeze-dried in the presence of cryoprotectants had comparable survivability during storage at 4 °C whereas the survival rate at 25 °C of cells protected by cellobiose and FOS was higher than for those protected with sucrose and trehalose. Furthermore, the respective excipients used as cryoprotectants enhanced the stability of cells exposed to simulated gastric and small intestinal medium. Stabilization may be achieved through different mechanism of action such as protecting the membrane integrity and as metabolizable substrates. Overall, prebiotic and thus metabolizable protectants including cellobiose and FOS were superior to other protectants used. Conclusion: In symbiotic formulas with B. infantis, these sugars might serve as prebiotics and stabilizers of this probiotic strain during lyophilization, storage and in gastrointestinal conditions simultaneously, potentially increasing its health-promoting effects.


Assuntos
Bifidobacterium longum subspecies infantis/crescimento & desenvolvimento , Excipientes , Prebióticos/microbiologia , Trato Gastrointestinal , Probióticos
2.
Contrast Media Mol Imaging ; 2018: 1269830, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29666562

RESUMO

Molecular imaging probes such as PET-tracers have the potential to improve the accuracy of tumor characterization by directly visualizing the biochemical situation. Thus, molecular changes can be detected early before morphological manifestation. The A3 adenosine receptor (A3AR) is described to be highly expressed in colon cancer cell lines and human colorectal cancer (CRC), suggesting this receptor as a tumor marker. The aim of this preclinical study was the evaluation of [18F]FE@SUPPY as a PET-tracer for CRC using in vitro imaging and in vivo PET imaging. First, affinity and selectivity of FE@SUPPY and its metabolites were determined, proving the favorable binding profile of FE@SUPPY. The human adenocarcinoma cell line HT-29 was characterized regarding its hA3AR expression and was subsequently chosen as tumor graft. Promising results regarding the potential of [18F]FE@SUPPY as a PET-tracer for CRC imaging were obtained by autoradiography as ≥2.3-fold higher accumulation of [18F]FE@SUPPY was found in CRC tissue compared to adjacent healthy colon tissue from the same patient. Nevertheless, first in vivo studies using HT-29 xenografts showed insufficient tumor uptake due to (1) poor conservation of target expression in xenografts and (2) unfavorable pharmacokinetics of [18F]FE@SUPPY in mice. We therefore conclude that HT-29 xenografts are not adequate to visualize hA3ARs using [18F]FE@SUPPY.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Ácidos Nicotínicos/farmacocinética , Tomografia por Emissão de Pósitrons/métodos , Animais , Radioisótopos de Flúor , Células HT29 , Xenoenxertos , Humanos , Camundongos , Imagem Molecular/métodos , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Receptor A3 de Adenosina/análise , Receptor A3 de Adenosina/metabolismo
3.
Benef Microbes ; 5(3): 263-72, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24675230

RESUMO

During the last years, the application of probiotics in gynaecological clinical practice has gained increasing relevance regarding therapy and prevention. This trend has also provoked the need for having tailored pharmaceutical preparations containing powerful microbial strains with defined properties. For the development of such preparations, several factors and criteria have to be considered, thereby not only focusing on identity and safety aspects as well as individual properties of the bacterial strains, but also on technological issues, such as stability and targeted release from the preparation. Against this background, this report exemplarily addresses the development procedure of a probiotic bacterial formulation for gynaecological application, covering the search for suitable strains, assessing their microbiological, molecular biological and physiological characterisation, and the selection for their use in clinical trials. In detail, starting with 127 presumptive lactobacilli isolates of vaginal origin, a step-by-step selection of candidate strains meeting special criteria was thoroughly examined, finally leading to a preparation consisting of four individual Lactobacillus strains that possess particular significance in women's urogenital health. Relevant issues and quality criteria of probiotic preparations used in gynecology are addressed and exemplarily introduced.


Assuntos
Anti-Infecciosos/uso terapêutico , Lactobacillus/isolamento & purificação , Probióticos/uso terapêutico , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/microbiologia , Técnicas de Tipagem Bacteriana , Feminino , Humanos , Lactobacillus/classificação , Tipagem Molecular , Vagina/microbiologia , Vaginose Bacteriana/prevenção & controle
4.
Appl Radiat Isot ; 70(10): 2287-94, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22858577

RESUMO

The melanin concentrating hormone (MCH) system is a new target to treat human disorders. Our aim was the preparation of the first PET-tracer for the MCHR1. [(11)C]SNAP-7941 is a carbon-11 labeled analog of the published MCHR1 antagonist SNAP-7941. The optimum reaction conditions were 2 min reaction time, ≤25°C reaction temperature, and 2 mg/mL precursor (SNAP-acid) in acetonitrile, using [(11)C]CH(3)OTf as methylation agent. [(11)C]SNAP-7941 was prepared in a reliable and feasible manner with high radiochemical yields (2.9±1.6 GBq; 11.5±6.4% EOB, n=15).


Assuntos
Radioisótopos de Carbono/química , Piperidinas/síntese química , Tomografia por Emissão de Pósitrons , Pirimidinas/síntese química , Receptores de Somatostatina/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Controle de Qualidade
5.
Gesundheitswesen ; 74(10): e90-8, 2012 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-22422076

RESUMO

OBJECTIVES: We examined the financial burden of osteoporosis in Austria. METHODS: We took both direct and indirect costs into consideration. Direct costs encompass medical costs such as expenses for pharmaceuticals, inpatient and outpatient medical care costs, as well as other medical services (e.g., occupational therapies). Non-medical direct costs include transportation costs and medical devices (e.g., wheel chairs or crutches). Indirect costs refer to costs of productivity losses due to absence of work. Moreover, we included costs for early retirement and opportunity costs of informal care provided by family members. While there exist similar studies for other countries, this is the first comprehensive study for Austria. For our analysis, we combined data of official statistics, expert estimates as well as unique patient surveys that are currently conducted in the course of an international osteoporotic fracture study in Austria. RESULTS: Our estimation of the total annual costs in the year 2008 imposed by osteoporosis in Austria is 707.4 million €. The largest fraction of this amount is incurred by acute hospital treatment. Another significant figure, accounting for 29% of total costs, is the opportunity cost of informal care. CONCLUSIONS: The financial burden of osteoporosis in Austria is substantial. Economic evaluations of preventive and therapeutic interventions for the specific context of Austria are needed to inform health policy decision makers.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Hospitalização/economia , Programas Nacionais de Saúde/economia , Fraturas por Osteoporose/economia , Assistência ao Paciente/economia , Assistência Ambulatorial/economia , Áustria , Cuidadores/economia , Custos e Análise de Custo , Custos de Medicamentos/estatística & dados numéricos , Feminino , Traumatismos do Antebraço/economia , Traumatismos do Antebraço/prevenção & controle , Política de Saúde/economia , Fraturas do Quadril/economia , Fraturas do Quadril/prevenção & controle , Serviços de Assistência Domiciliar/economia , Assistência Domiciliar/economia , Humanos , Fraturas do Úmero/economia , Fraturas do Úmero/prevenção & controle , Tempo de Internação/economia , Masculino , Fraturas por Osteoporose/prevenção & controle , Pensões/estatística & dados numéricos , Fraturas das Costelas/economia , Fraturas das Costelas/prevenção & controle , Fraturas da Coluna Vertebral/economia , Fraturas da Coluna Vertebral/prevenção & controle
6.
Appl Radiat Isot ; 69(9): 1212-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21550258

RESUMO

[(11)C]PIB is still the standard PET compound for Alzheimer imaging targeting beta-amyloid plaques. We aimed to establish a fully-automated procedure for the synthesis and purification of [(11)C]PIB with a high degree of reliability and improved specific activity as well as a suitable and fast quality control assay. The optimum reaction conditions were 75°C, 4 mg/mL precursor yielding at 48.0±2.7% (EOS, based on [(11)C]CH(3)OTf, corrected for decay), 183±14 GBq/µmol specific activity and >99% radiochemical purity. Time consumption was kept to a minimum (40 min from EOB) and overall yields were enough to serve 2 consecutive patients with a single preparation.


Assuntos
Benzotiazóis/síntese química , Marcação por Isótopo/métodos , Compostos Radiofarmacêuticos/síntese química , Doença de Alzheimer/diagnóstico por imagem , Compostos de Anilina , Automação Laboratorial/métodos , Radioisótopos de Carbono , Humanos , Placa Amiloide/diagnóstico , Placa Amiloide/patologia , Cintilografia , Tiazóis
7.
Osteoarthritis Cartilage ; 18(2): 240-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19800998

RESUMO

OBJECTIVE: Sialic acids frequently occur at the terminal positions of glycoprotein N-glycans present at chondrocyte surfaces or in the cartilage matrix. Sialic acids are transferred to glycoproteins in either alpha-2,3 or alpha-2,6 linkage by specific sialyltransferases (SiaTs) and can potentially affect cell functions and cell-matrix interactions. The present study aimed to assess the relationship between the expression of the human chondrocyte phenotype and the sialylation of chondrocyte glycoprotein N-glycans. METHODS: The transcription of 5 SiaT was quantified using real-time Reverse transcription polymerase chain reaction (RT-PCR) assays. N-glycan analysis was performed using LC-ESI-MS. Primary human chondrocytes were cultured in monolayer or alginate beads and compared to the chondrocyte cell lines C-28/I2 and SW1353. In addition, effects of interleukin-1beta (IL-1beta) or tumour necrosis factor-alpha (TNF-alpha) on primary cells were assessed. RESULTS: Primary human chondrocytes predominantly express alpha-2,6-specific SiaTs and accordingly, alpha-2,6-linked sialic acid residues in glycoprotein N-glycans. In contrast, the preponderance of alpha-2,3-linked sialyl residues and, correspondingly, reduced levels of alpha-2,6-specific SiaTs are associated with the altered chondrocyte phenotype of C-28/I2 and SW1353 cells. Importantly, a considerable shift towards alpha-2,3-linked sialic acids and alpha-2,3-specific SiaT mRNA levels occurred in primary chondrocytes treated with IL-1beta or tumour necrosis factor-alpha (TNF-alpha). CONCLUSION: The expression of the differentiated chondrocyte phenotype is linked to the ratio of alpha-2,6- to alpha-2,3-linked sialic acids in chondrocyte glycoprotein N-glycans. A shift towards altered sialylation might contribute to impaired cell-matrix interactions in disease conditions.


Assuntos
Condrócitos/metabolismo , Glicoproteínas/química , Sialiltransferases/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Condrócitos/efeitos dos fármacos , Citocinas/farmacologia , Expressão Gênica , Humanos , Interleucina-1beta/farmacologia , Fenótipo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sialiltransferases/química , Sialiltransferases/genética , Fator de Necrose Tumoral alfa/farmacologia
8.
Appl Radiat Isot ; 68(3): 399-403, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20022514

RESUMO

For the development and process optimization of pharmaceutical equipment, it is important to investigate the underlying processes. Taking the fluidized bed technology as an example, the study of particle flow pattern and convection of the particles within the functional unity is essential for construction and process improvement. With positron emission particle tracking (PEPT) it is possible to study the real-time particle motion with radiolabelled particles. We established a fast and simple labelling technique with [(18)F]fluoride for pellets composed of Avicel and anion exchange resin. The uptake of activity ranged from 1.3% to 1.7% per mg and 8.6% to 16.3% per pellet. A specific binding of [(18)F]fluoride with increasing degree of anion exchange resin in the pellets could be observed.


Assuntos
Celulose/química , Radioisótopos de Flúor/química , Resinas de Troca Iônica/química , Marcação por Isótopo/métodos , Tecnologia Farmacêutica/métodos , Tomografia por Emissão de Pósitrons
9.
In Vitro Cell Dev Biol Anim ; 45(7): 351-60, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19263178

RESUMO

In vitro studies using chondrocyte cell cultures have increased our understanding of cartilage physiology and the altered chondrocytic cell phenotype in joint diseases. Beside the use of primary cells isolated from cartilage specimens of donors, immortalized chondrocyte cell lines such as C-28/I2 and T/C-28a2 have facilitated reproducible and standardized experiments. Although carbohydrate structures appear of significance for cartilage function, the contribution of the chondrocyte glycocalyx to matrix assembly and alterations of the chondrocyte phenotype is poorly understood. Therefore, the present study aimed to evaluate the glycoprofile of primary human chondrocytes as well as of C-28/I2 and T/C-28a2 cells in culture. First, the chondrocytic phenotype of primary and immortalized cells was assessed using real-time reverse transcriptase polymerase chain reaction, immunofluorescence, and glycosaminoglycans staining. Then, a panel of lectins was selected to probe for a range of oligosaccharide sequences determining specific products of the O-glycosylation and N-glycosylation pathways. We found that differences in the molecular phenotype between primary chondrocytes and the immortalized chondrocyte cell models C-28/I2 and T/C-28a2 are reflected in the glycoprofile of the cells. In this regard, the glycocalyx of immortalized chondrocytes was characterized by reduced levels of high-mannose type and sialic acid-capped N-glycans as well as increased fucosylated O-glycosylation products. In summary, the present report emphasizes the glycophenotype as an integral part of the chondrocyte phenotype and points at a significant role of the glycophenotype in chondrocyte differentiation.


Assuntos
Condrócitos/metabolismo , Lectinas/metabolismo , Diferenciação Celular , Linhagem Celular , Condrócitos/citologia , Citometria de Fluxo , Glicocálix/fisiologia , Glicosaminoglicanos/metabolismo , Humanos , Modelos Biológicos , Fenótipo
10.
Osteoarthritis Cartilage ; 16(10): 1205-12, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18321735

RESUMO

OBJECTIVE: To compare the effects of glucosamine (GlcN), curcumin, and diacerein in immortalized human C-28/I2 chondrocytes at the cellular and the gene expression level. This study aimed to provide insights into the proposed beneficial effects of these agents and to assess the applicability of the C-28/I2 cell line as a model for the evaluation of chondroprotective action. METHODS: Interleukin-1beta (IL-1beta)-stimulated C-28/I2 cells were cultured in the presence of GlcN, curcumin, and diacerein prior to the evaluation of parameters such as viability, morphology and proliferation. The impact of GlcN, curcumin, and diacerein on gene expression was determined using quantitative real-time RT-PCR (qPCR). RESULTS: At the transcriptional level, 5 mM GlcN and 50 microM diacerein increased the expression of cartilage-specific genes such as aggrecan (AGC) and collagen type II (COL2), while reducing collagen type I (COL1) mRNA levels. Moreover, the IL-1beta-mediated shift in gene expression pattern was antagonized by GlcN and diacerein. These effects were associated with a significant reduction in cellular proliferation and the development of chondrocyte-specific cell morphology. In contrast, curcumin was not effective at lower concentrations but even damaged the cells at higher amounts. CONCLUSIONS: Both GlcN and diacerein promoted a differentiated chondrocytic phenotype of immortalized human C-28/I2 chondrocytes by altering proliferation, morphology, and COL2/COL1 mRNA ratios. Moreover, both agents antagonized inhibitory effects of IL-1beta by enhancing AGC and COL2 as well as by reducing COL1 mRNA levels.


Assuntos
Antraquinonas/farmacologia , Condrócitos/efeitos dos fármacos , Curcumina/farmacologia , Glucosamina/farmacologia , Osteoartrite/metabolismo , Substâncias Protetoras/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas/metabolismo , Expressão Gênica/efeitos dos fármacos , Glucosamina/genética , Humanos , Interleucina-1beta/genética , Modelos Biológicos , Osteoartrite/genética , Reação em Cadeia da Polimerase
11.
BJOG ; 114(11): 1402-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17877778

RESUMO

OBJECTIVE: This study was undertaken to characterise the dominant species of Lactobacillus colonising the vagina of healthy pregnant women, to examine some of their phenotypic and genotypic properties, and to gain a better understanding of the potential role of species, which might be associated with infection-free status. DESIGN: A prospective descriptive cohort study. SETTING: Department of Obstetrics and Gynaecology, Medical University of Vienna and Medical School, Vienna, Austria. SAMPLE: A total of 200 women in the late first trimester of pregnancy without clinical signs of vaginal infection were included in the study. Of these, 126 women were found to have a normal vaginal flora based on Gram stain. METHODS: Culture probes from those 126 women were further processed for identification of Lactobacillus species. Overall, 168 colonies from 84 women were identified as belonging to the Lactobacillus genus. Based on the combined results of microbiological methods and genus-specific, multiplex, and species-specific polymerase chain reaction, lactobacilli were recovered from 72 women. MAIN OUTCOME MEASURES: Identification of Lactobacillus species of the vaginal flora of healthy pregnant women. RESULTS: The most frequently occurring species were Lactobacillus crispatus and Lactobacillus gasseri, followed by Lactobacillus jensenii and Lactobacillus rhamnosus. CONCLUSIONS: Our results may have implications on the composition and on the use of Lactobacillus preparations for the prevention of recurrent vaginal infection.


Assuntos
Lactobacillus/isolamento & purificação , Gravidez/fisiologia , Vagina/microbiologia , Adolescente , Adulto , Estudos de Coortes , Feminino , Genótipo , Humanos , Lactobacillus/genética , Fenótipo , Reação em Cadeia da Polimerase/métodos , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Esfregaço Vaginal/métodos
12.
J Control Release ; 117(1): 121-9, 2007 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-17126445

RESUMO

The present study was performed to evaluate the applicability of plant lectins as mediators of bioadhesion in cartilage research using human chondrocyte cell lines C-28/I2 and T/C-28a2. The bioadhesive properties of fluorescein-labelled lectins with different carbohydrate specificities were investigated by flow cytometry. Specificity of the lectin-cell interactions was ascertained by competitive inhibition using complementary carbohydrates. As compared to that of other lectins, the interaction between wheat germ agglutinin (WGA) and chondrocytic cells was characterised by remarkable cytoadhesion, adequate binding strength and a high degree of specificity for N-acetyl-glucosamine as contained in hyaluronan chains. We therefore suggest WGA to be a promising candidate for mediating bioadhesion to low-adhesive scaffolds in cartilage tissue engineering. Moreover, the WGA-association rate of C-28/I2 and T/C-28a2 cells was dependent on temperature indicating cellular uptake of membrane-bound WGA. Intracellular enrichment was confirmed by confocal microscopy. Equilibration of intracellular pH gradients with monensin resulted in the reversal of quenching effects indicating accumulation of WGA within acid compartments of chondrocytic cells. Thus, WGA might be internalised into chondrocytes together with hyaluronan via the CD44 receptor-mediated endocytosis pathway and accumulated within lysosomes. This physiological process could represent a feasible pathway to target WGA-functionalised drug delivery devices into chondrocytes.


Assuntos
Cartilagem/fisiologia , Condrócitos/metabolismo , Sistemas de Liberação de Medicamentos , Engenharia Tecidual , Acetilglucosamina , Ligação Competitiva/efeitos dos fármacos , Carboidratos/química , Cartilagem/citologia , Adesão Celular , Linhagem Celular , Sobrevivência Celular , Citometria de Fluxo , Humanos , Ácido Hialurônico/química , Lectinas , Microscopia Confocal , Aglutininas do Germe de Trigo
13.
Eur J Med Res ; 11(1): 7-12, 2006 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-16504954

RESUMO

PURPOSE: Monocytes derived from patients with early breast cancer (EBC) have shown functional deficiencies. These functional deficiencies are characterized by changes in phenotype and morphology. We have expanded these investigations to dendritic cells generated from monocytes from patients with early breast cancer. - PATIENTS AND METHODS: Peripheral blood from 36 patients with EBC and from 26 healthy age-matched women was drawn and prepared for ex vivo generation of dendritic cells (DC) by incubation with granulocyte/macrophage-colony stimulating factor (GM-CSF) and interleukin 4 (IL4). The phenotype of DC was examined by flow-cytometry. T cell - proliferation was induced with tetanus toxoid pulsed autologous dendritic cell. - RESULTS: Dendritic cells generated from monocytes from EBC-patients showed a significantly lower expression of the phenotype-associated antigens CD1a, CD83, CD80, CD86 and CD54 than the dendritic cells from healthy controls. T cell - proliferation in response to TT-pulsed autologous dendritic cells was significantly decreased when induced with dendritic cells from patients with early breast cancer, when compared to healthy controls. Morphologically, only dendritic cells from healthy women possessed prominent dendrites indicating maturity. - CONCLUSIONS: These findings indicate that dendritic cells generated from monocytes from patients with early breast cancer express an immature phenotype, exhibit immature morphology and show functional deficits when compared to the cells derived from healthy age-matched controls. Whether these findings offer a potential target for therapeutic interventions remains to be elucidated.


Assuntos
Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apresentação de Antígeno , Antígenos CD/biossíntese , Neoplasias da Mama/patologia , Células Cultivadas , Feminino , Humanos , Pessoa de Meia-Idade , Fenótipo , Índice de Gravidade de Doença , Toxoide Tetânico/imunologia
14.
J Microencapsul ; 21(3): 317-30, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15204598

RESUMO

The negative aspects of chemical pesticides are of growing concern to the public. Thus, there is a strong effort to exploit environmentally friendly possibilities for pest management. One strategy is the application of biocontrol agents such as the fungus Beauveria brongniartii. In this context, the central objective of the research presently described is to investigate spray drying as a preservation method for fungal conidia to obtain a practical formulation for spray application. An aqueous binary mixture composed of skim milk (SM) and polyvinylpyrrolidone (PVP K90) was examined as encapsulation matrix. The influence of different inlet/outlet temperature adjustments, the composition of the carrier system and the conidia concentration were examined with respect to their influence on spore viability. Results indicate that air outlet temperatures up to 53 +/- 2 degrees C resulted in a slight reduction of conidial viability (approximately 3%). Microencapsulated conidia have been subjected to storage tests with and without the addition of silica gel capsules at various temperatures. Results show that survival is inversely related to storage temperatures and residual moisture levels of the spray dried powders. The highest survival rates were observed at moisture contents of 3% and a temperature of 10 degrees C. Moreover, production characteristics like entrapment efficacy, shape and size were investigated. Furthermore, the composition of the carrier matrix was optimised to result in production yields of 25%. Results show that spray drying is a useful, economic encapsulation technology for aerial conidia of Beauveria brongniartii resulting in highly concentrated, spray dried powders of 92% viability.


Assuntos
Composição de Medicamentos/métodos , Fungos Mitospóricos , Controle Biológico de Vetores , Animais , Bovinos , Dessecação , Leite , Polivinil , Esporos Fúngicos , Temperatura
15.
Int J Pharm ; 256(1-2): 117-22, 2003 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-12695017

RESUMO

In the present study, gastric juice resistant tablet formulations of lactic acid bacteria (LAB) were developed, using hydroxypropylmethylcellulose acetate succinate (HPMCAS) as well as alginates, apple pectin and Metolose as matrix forming components. To optimize the formulation-using survival rate in acid medium, and disintegration time in intestinal fluid as test parameters-tablets were modified with respect to LAB content, amount of applied excipients per tablet, and compaction forces. A decrease of viable cells of not more than one log unit after 2h of incubation in acid medium was desired, as well as a disintegration time of 1h in phosphate buffer pH 6.8. It was found that the amount of HPMCAS in the tablet correlates with gastric juice resistance. As HPMCAS also leads to a decrease of disintegration time in intestinal fluid, slight amounts of this excipient were preferred. The best protective qualities against artificial gastric juice were observed when tablets were prepared from compaction mixtures of LAB, HPMCAS and sodium alginate.


Assuntos
Ácido Láctico/química , Lactobacillus acidophilus , Metilcelulose/análogos & derivados , Probióticos/química , Contagem de Colônia Microbiana , Força Compressiva , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes/química , Suco Gástrico/química , Concentração de Íons de Hidrogênio , Lactobacillus acidophilus/isolamento & purificação , Metilcelulose/química , Solubilidade , Comprimidos com Revestimento Entérico , Temperatura
16.
Int J Pharm ; 256(1-2): 175-81, 2003 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-12695024

RESUMO

Pyrethrum extract, containing six insecticidal esters, has a long history of successful application in the control of stored products. Its low environmental hazard makes it an ideal pesticide for outdoor pre-harvest treatment. However the disadvantage of its low light stability then becomes apparent. This drawback can be overcome by the complexation of pyrethrum extract with gamma-cyclodextrin. Primary object of the conducted studies was to investigate the effect of complexation upon the insecticidal action against the grain weevil, an important storage pest in temperate climates. To slow down the quick metabolism of pyrethrum by the insects' microsomal system synergistic substances are added. Additional to the already well-known piperonyl butoxide two natural synergists, sesamol and tocopherol acetate, were combined with pyrethrum extract to investigate their synergistic activity. A complex of pyrethrum with gamma-cyclodextrin, with piperonyl butoxide as synergist, has a slightly enhanced action compared to a commercial product, which contained pyrethrum in its free form. Sesamol and tocopherol acetate also display a synergistic action, but to a much smaller degree, even if applied in larger amounts. The optimal concentration of pyrethrum was found to be 0.3% combined with 3% piperonyl butoxide.


Assuntos
Inseticidas/química , Piretrinas/química , alfa-Tocoferol/análogos & derivados , gama-Ciclodextrinas , Animais , Benzodioxóis , Besouros , Ciclodextrinas/química , Sinergismo Farmacológico , Fenóis/química , Butóxido de Piperonila/química , Fatores de Tempo , Tocoferóis , alfa-Tocoferol/química
17.
J Microencapsul ; 19(5): 641-59, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12433306

RESUMO

Alginate beads, as well as microcapsules based on alginate, cellulose sulphate and polymethylene-co-guanidine, were produced at diameters of 0.4, 1.0 and 1.5 mm. These standard materials were tested, by independent laboratories, in regards to water activity, bead or capsule size, mechanical resistance and transport behaviour. The water activity and mechanical resistance were observed to increase with bead and capsule size. Transport properties (ingress) were assessed using a variety of low molar mass and macromolecular probes. It was observed that the penetration of Vitamin B12 increased with bead diameter, as did dextran penetration. However, for the membrane-containing microcapsules, larger membrane thickness, observed for the larger capsules, retarded ingress. The authors, who are part of a European working group, recommend that permeability be assessed either using a large range of probes or a broad molar mass standard, with measurements at one or two molar masses insufficient to simulate the behaviour in application. Mechanical compression is seen as a good means to estimate elasticity and rupture of beads and capsules, with the sensitivity of the force transducer, which can vary from microN to tens of N, required to be tuned to the anticipated bead or capsule strength. Overall, with the exception of the mechanical properties, the precision in the inter-laboratory testing was good. Furthermore, the various methods of assessing transport properties agreed, in ranking, for the beads and capsules characterized, with gels having smaller radii being less permeable. For microcapsules, the permeation across the membrane dominates the ingress, and thicker membranes have lower permeability.


Assuntos
Cápsulas/química , Alginatos/síntese química , Alginatos/química , Fenômenos Biomecânicos , Cápsulas/síntese química , Dextranos , Composição de Medicamentos , Géis , Ácido Glucurônico , Ácidos Hexurônicos , Técnicas In Vitro , Tamanho da Partícula , Permeabilidade , Propriedades de Superfície , Vitamina B 12/administração & dosagem , Vitamina B 12/farmacocinética , Água
18.
J Appl Microbiol ; 93(4): 521-30, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12234334

RESUMO

AIMS: This study was undertaken to characterize and differentiate therapeutically relevant Saccharomyces yeasts. Among the isolates were so-called Saccharomyces boulardii strains, which are considered as probiotic agents, but whose taxonomic assignment is controversial. Moreover, the discriminative power of the applied molecular typing techniques should be evaluated. METHODS AND RESULTS: Genotyping was performed using species-specific polymerase chain reaction (PCR), randomly amplified polymorphic DNA-PCR, restriction fragment length polymorphism analysis of rDNA spacer regions and pulsed-field gel electrophoresis. Species-specific PCR assigned all of the product isolates to the species S. cerevisiae. By combining the other techniques, all isolates could be discriminated. Moreover, it could be demonstrated that probiotic S. boulardii strains form a separate cluster located within the species. CONCLUSIONS: With the exception of species-specific PCR, all of the applied methodologies were suitable for subspecies typing and indicated a close relationship between the probiotic strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The methods applied in this study are considered powerful tools for quality control of therapeutically relevant yeasts. It is of crucial importance, especially regarding S. boulardii yeasts, to verify the identity of the correct strain, since the beneficial properties are considered to be strain-specific.


Assuntos
Probióticos , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/genética , Saccharomyces/classificação , Saccharomyces/genética , DNA Fúngico/análise , DNA Espaçador Ribossômico/análise , Eletroforese em Gel de Campo Pulsado , Técnicas de Tipagem Micológica , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
19.
Lett Appl Microbiol ; 33(4): 251-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11559396

RESUMO

AIMS: To investigate 17 strains of therapeutically relevant strains of Saccharomyces cerevisiae (including 10 strains of so-called S. boulardii) isolated from various pharmaceutical products, feed supplements and brewer's yeast for their capability of utilizing selected carbohydrates of prebiotic importance. METHODS AND RESULTS: Automated turbidimetric measurements and conventional test combinations were used to examine the basic sugar assimilation profiles of the test strains. It was shown that none of the so-called S. boulardii strains utilized galactose and palatinose. Among the prebiotic substrates, the yeasts indicated a pronounced preference for metabolizing the fructo-oligosaccharides. CONCLUSION: Yeast strains of therapeutic relevance can be successfully combined with certain prebiotics in symbiotic formulations. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study may serve as a basis for the development of new pharmaceutical preparations for medical therapy and a better understanding of intestinal micro-ecology.


Assuntos
Metabolismo dos Carboidratos , Saccharomyces cerevisiae/metabolismo , Intestinos/microbiologia , Nefelometria e Turbidimetria , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/crescimento & desenvolvimento
20.
Pharm Res ; 17(3): 358-65, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10801226

RESUMO

PURPOSE: In the present paper, linear and nonlinear models for complexation of alpha- beta- and gamma-cyclodextrin with guest molecules are developed, with the aim of free energy prediction and interpretation of the association process. METHODS: Linear and nonlinear regression is used to correlate experimental free energies of complexation with calculated molecular descriptors. Molecular modeling supports the interpretation of the results. RESULTS: Highly predictive models are obtained, although the structural variability of the compounds used for their deduction is large, reaching from synthetic heterocycles to steroids and prostaglandins. CONCLUSIONS: The scaled regression coefficients give insight to the complexation mechanisms, which appear to be different for the three types of cyclodextrins.


Assuntos
Ciclodextrinas/química , Transferência de Energia , Modelos Lineares , Dinâmica não Linear , Relação Estrutura-Atividade , alfa-Ciclodextrinas , beta-Ciclodextrinas , gama-Ciclodextrinas , Modelos Moleculares , Preparações Farmacêuticas/química , Estrutura Terciária de Proteína
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