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1.
Materials (Basel) ; 16(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36676289

RESUMO

Semiconductor quantum dots of the A2B6 group and organic semiconductors have been widely studied and applied in optoelectronics. This study aims to combine CdTe quantum dots and perylene-based dye molecules into advanced nanostructure system targeting to improve their functional properties. In such systems, new electronic states, a mixture of Wannier-Mott excitons with charge-transfer excitons, have appeared at the interface of CdTe quantum dots and the perylene dye. The nature of such new states has been analyzed by absorption and photoluminescence spectroscopy with picosecond time resolution. Furthermore, aggregation of perylene dye on the CdTe has been elucidated, and contribution of Förster resonant energy transfer has been observed between aggregated forms of the dye and CdTe quantum dots in the hybrid CdTe-perylene nanostructures. The studied nanostructures have strongly quenched emission of quantum dots enabling potential application of such systems in dissociative sensing.

2.
Rev Sci Instrum ; 93(3): 033903, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365002

RESUMO

We demonstrate the potential of using digital stereo micro-photogrammetry for the analysis and modeling of the habit and sectoral structure of real high-pressure high-temperature single-crystal diamonds. A prototype scanning system with a resolution of 5 µm has been implemented based on a digital single-lens reflex camera, making it possible to create highly accurate reproductions of crystal shapes with a minimum size of 4 mm. This method makes it possible to monitor the effect of actual conditions on the physical processes of crystal growth, which is a useful advance for the development of active device elements based on semiconductor diamonds.

3.
Wiad Lek ; 75(1 pt 2): 251-258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35182131

RESUMO

OBJECTIVE: The aim: To obtain the first estimates of the current incidence, and risk factors for Surgical Site Infection (SSI) after laparoscopic hysterectomy, and antimicrobial resistance of responsible pathogens in Ukraine. PATIENTS AND METHODS: Materials and methods: We performed a multicenter prospective cohort study was patient-based on surveillance data for SSIs were according to CDC/NHSN methodology. This study included women's undergoing a laparoscopic hysterectomy in 8 hospitals from different regions of Ukraine from January 2018 to December 2020. RESULTS: Results: A total of 1184 women underwent a laparoscopic hysterectomy and 14.9% SSI were identified within 30 days of the operation. Majority of SSI were deep/organ-space. The deep/organ-space SSI incidence rate was 9.2% in total laparoscopic hysterectomy, 15.2% in laparoscopic-assisted vaginal hysterectomy, and 17% in laparoscopic supracervical hysterectomy. The predominant SSI types were Pelvic abscess or cellulitis (19.1%), Salpingitis (16%), Oophoritis (15.3%), Adnexa utery (14.5%), Vaginal cuff infections (13.7%), Endometritis (11.1%), and Chorioamnionitis (9.9%). 93.8% of SSIs were detected post discharge. The most commonly identified pathogen were Escherichia coli (21.6%), Enterobacter spp. (13.1%), followed by Klebsiella spp. (8,1%), Streptococcus spp. (7%), and Pseudomonas aeruginosa (7%). The overall proportion of extended spectrum beta-lactamase production (ESBL) among Enterobacteriaceae was 17.1% and of methicillin-resistance in S. aureus (MRSA)15.8%. Resistance to third-generation cephalosporins was observed in 13.7% E.coli and 8.5% Klebsiella spp. isolates. Carbapenem resistance was in 9.7% of P.aeruginosa strains. CONCLUSION: Conclusions: Our study identified high incidence rates of SSI within 30 days surveillance of the laparoscopic hysterectomy in Ukraine, and many cases were caused by pathogens that are resistant to antibiotics.


Assuntos
Laparoscopia , Infecção da Ferida Cirúrgica , Assistência ao Convalescente , Antibacterianos/uso terapêutico , Estudos de Coortes , Farmacorresistência Bacteriana , Feminino , Humanos , Histerectomia/efeitos adversos , Alta do Paciente , Gravidez , Estudos Prospectivos , Estudos Retrospectivos , Staphylococcus aureus , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Ucrânia
4.
Wiad Lek ; 74(6): 1510-1514, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34159947

RESUMO

OBJECTIVE: The aim: To present data on the possibility of occurrence and active progression of generalized periodontitis in persons with secretory immunoglobulin A deficiency and possible methods of its correction. PATIENTS AND METHODS: Мaterials and methods: Analytical elaboration of scientific and medical literature based on the immunological aspect of generalized periodontitis. CONCLUSION: Conclusions: The deficiency of secretory immunoglobulin A may occur in cases of primary or secondary insufficiency of the immune system. Selective IgA deficiency is an example of primary insufficiency of the immune system. Secondary immunodeficiency disorders is a clinical and immunological syndrome that develops against the background of a previously normally functioning immune system, characterized by a steady decrease in quantitative or functional indicators of specific or(and) nonspecific factors of immunoresistance. Insufficient awareness of dentists about certain aspects of the etiology and pathogenesis of generalized periodontitis leads to deterioration of treatment results.


Assuntos
Deficiência de IgA , Periodontite , Humanos , Imunoglobulina A , Imunoglobulina A Secretora , Periodontite/complicações , Periodontite/terapia
5.
Wiad Lek ; 73(8): 1677-1680, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33055333

RESUMO

OBJECTIVE: The aim of this study was to compare the wear resistance of such restorative materials as composite resin, feldspathic ceramic, leucite glass ceramic with intact enamel and to draw an analogy with some similar researches. PATIENTS AND METHODS: Materials and methods: In this research 20 extracted human teeth (maxillary incisors) without fillings and carious cavities were used as samples. All samples were disinfected and stored in saline in order to prevent dehydration. Teeth roots were cut off for the measure of fixation on an organic glass plate using chemically polymerizable resin. If necessary, the teeth were also cut on their lateral sides in order to give them equal size. The samples were placed in a frame-holder, located on the lever of the machine MI-2, which determines abrasion resistance under slipping. RESULTS: Results: The research has revealed that the average wear resistance of natural teeth was 122,67±4.9 J/mm3 (Tab 1). The archived result overcomes dental composite resin twice more (62.8±1.21 J/mm3), feldspathic ceramic 6.5 times more (16.32±1.2 J/mm3) and leucite ceramic over the half (73.79±3.12 J/mm3). CONCLUSION: Conclusion: Thus, according to this performed research and the analysis of the relative literature sources it can be stated that dental composite resin and leucite ceramics may be proposed as the materials of choice for anterior restoration of teeth. They have shown the good wear resistance and tolerance to antagonizing natural teeth.


Assuntos
Resinas Compostas , Desgaste dos Dentes , Cerâmica , Humanos
6.
Wiad Lek ; 73(7): 1561-1566, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32759455

RESUMO

OBJECTIVE: The aim: was toanalyze the scientific and pedagogical heritage of N.I. Pirogov, which remains relevant in the modern medical and pedagogical community, and opens new little-known pages of the scientific, pedagogical and medical activity of the doctor. PATIENTS AND METHODS: Materials and methods: The authors conducted a thorough analysis of scientific publications by N.I. Pirogov and papers devoted to his activity as a doctor, educator and researcher using analytical, comparative and bibliosemantic methods. CONCLUSION: Conclusions: The study suggested the new chronological boundaries in the scientific and educational heritage of N.I. Pirogov. The developed periodization accurately reflects the beginning of his scientific and pedagogical path in medical education, specifically refers to the period of his work in Germany as a supervisor of professorial candidates from 1862 to 1866, and the period of his participation in Sevastopol (Crimean) campaign and in the Franco-Prussian War, which was very important for the development of military field surgery.


Assuntos
Educação Médica , Médicos
7.
Wiad Lek ; 73(2): 360-364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32248175

RESUMO

OBJECTIVE: The aim: The aim of the study is a statistical analysis of the mucosa of the stomach affected by Helicobacter pylori in young people studying at the university. PATIENTS AND METHODS: Materials and methods: The work contains the results of the study of chronic gastritis of type B in university volunteer students. The study was attended by students of 1-4courses, aged 17 to 25 years, a total of 50 people. Among them were 28 men and 22 women. RESULTS: Results: Various forms of chronic gastritis were found in the mucosa of the topographic-anatomical sections of the stomach, 90% of which were associated with Helicobacterpylori (HP). In all departments there is a different amount of common forms of chronic gastritis. In the pyloric section only atrophic gastritis was detected - 31.0 ± 8.5. Atrophic gastritis was also dominant on the lesser curvature - 32.3 ± 7.8, but its forms were significantly (p <0.5) less pronounced than in the pyloric section. In the area of the body, the above variants of chronic gastritis were found in 34.3 ± 8.7 cases, and the majority were flat erosive gastritis 51.0 ± 9.3. There is a tendency to reduce the degree of bacterial contamination of the gastric mucosa from its pyloric section and the lesser curvature to the walls of the body. With a decrease in the degree of bacterial contamination of the gastric mucosa, the degree of leukocyte infiltration also decreases. Between the degree of contamination of the mucous membrane of Helicobacter pylori and the degree of leukocyte infiltration of the mucous membrane, the Pearson correlation coefficient is rxy - 0,935, the correlation is very strong, the coefficient of determination is D=rxy^2 - 0,874, the statistically significant dependence on the probability is 0.99. CONCLUSION: Conclusions: Atrophic or hyperplastic gastritis associated with HP is found in the gastric mucosa, respectively, 90% of cases. The degree of bacterial contamination correlates with the degree of leukocyte infiltration of the gastric mucosa. Atrophic or hyperplastic gastritis Helicobacter pylori-associated is a common disease of people in young and working age.


Assuntos
Gastrite , Adolescente , Adulto , Feminino , Mucosa Gástrica , Infecções por Helicobacter , Helicobacter pylori , Humanos , Masculino , Estudantes , Adulto Jovem
8.
JAMA Facial Plast Surg ; 21(6): 511-517, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31486840

RESUMO

IMPORTANCE: Preoperative assessment of nasal soft-tissue envelope (STE) thickness is an important component of rhinoplasty that presently lacks validated tools. OBJECTIVE: To measure and assess the distribution of nasal STE thickness in a large patient population and to determine if facial plastic surgery clinicians can predict nasal STE thickness based on visual examination of the nose. DESIGN, SETTING, AND PARTICIPANTS: This retrospective review and prospective assessment of 190 adult patients by 4 expert raters was conducted at an academic tertiary referral center. The patients had high-resolution maxillofacial computed tomography (CT) scans and standardized facial photographs on file and did not have a history of nasal fracture, septal perforation, rhinoplasty, or other surgery or medical conditions altering nasal form. Data were analyzed in March 2019. MAIN OUTCOMES AND MEASURES: Measure nasal STE thickness at defined anatomic subsites using high-resolution CT scans. Measure expert-predicted nasal STE thickness based on visual examination of the nose using a scale from 0 (thinnest) to 100 (thickest). RESULTS: Of the 190 patients, 78 were women and the mean (SD) age was 45 (17) years. The nasal STE was thickest at the sellion (mean [SD]) (6.7 [1.7] mm), thinnest at the rhinion (2.1 [0.7] mm), thickened over the supratip (4.8 [1.0] mm) and nasal tip (3.1 [0.6] mm), and thinned over the columella (2.6 [0.4] mm). In the study population, nasal STE thickness followed a nearly normal distribution for each measured subsite, with the majority of patients in a medium thickness range. Comparison of predicted and actual nasal STE thickness showed that experts could accurately predict nasal STE thickness, with the highest accuracy at the nasal tip (r, 0.73; prediction accuracy, 91%). A strong positive correlation was noted among the experts' STE estimates (r, 0.83-0.89), suggesting a high level of agreement between individual raters. CONCLUSIONS AND RELEVANCE: There is variable thickness of the nasal STE, which influences the external nasal contour and rhinoplasty outcomes. With visual analysis of the nose, experts can agree on and predict nasal STE thickness, with the highest accuracy at the nasal tip. These data can aid in preoperative planning for rhinoplasty, allowing implementation of preoperative, intraoperative, and postoperative strategies to optimize the nasal STE, which may ultimately improve patient outcomes and satisfaction. LEVEL OF EVIDENCE: NA.


Assuntos
Algoritmos , Nariz/anatomia & histologia , Exame Físico , Rinoplastia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
9.
Wiad Lek ; 71(6): 1129-1134, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30267488

RESUMO

OBJECTIVE: Introduction: Perceiving the high prevalence of direct composite restoration technique usage for the rehabilitation of patients with increased tooth wear, as well as during the sanitation of oral cavity before indirect methods of rehabilitation, there is a necessity in more detailed reasoning of adhesive system application for treatment of dentition with increased tooth wear. The aim: The purpose of our work was to study the microstructure and chemical compound of hard tissues of teeth on background of increased tooth wear with the presence of a carious process with the application of adhesive systems of 5th and 7th generation. PATIENTS AND METHODS: Materials and methods: The researche of teeth with physiological and increased tooth wear with the presence of carious process in the amount of 40 pcs. was carried out with the help of a raster electron microscope (SEM) Mira 3 LMU (Tescan, Czech Republic) with a maximum resolution of 1 nm and a maximum increase of 1 000 000. Elemental composition of the local area was determined using the X-max 80mm2 energy dissipation spectrometer ( Oxford Instruments, UK), integrated into a raster electron microscope. RESULTS: Results: The number of enamel prisms per square area in the case of increased tooth wear is 19 per 100 microns on average and 22.65 per 100 microns in carious teeth. CONCLUSION: Conclusions: Greater permeability is observed in the adhesive system of 7th generation (Adper Easy One), which allows it to be recommended for usege in the cases of severe caries and increased tooth wear.


Assuntos
Adesivos , Cárie Dentária , Esmalte Dentário/ultraestrutura , Desgaste dos Dentes , Humanos , Microscopia Eletrônica
10.
ACS Appl Mater Interfaces ; 10(7): 6755-6763, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29381323

RESUMO

We experimentally demonstrate that the conductivity of graded AlxGa1-xN increases as a function of the magnitude of the Al concentration gradient (%Al/nm) due to polarization doping effects, without the use of impurity dopants. Using three up/down-graded AlxGa1-xN nanolayers with Al gradients ranging from ∼0.16 to ∼0.28%Al/nm combined in one structure, the effects of polarization engineering for localized electric fields and current transport were investigated. Cross-sectional Kelvin probe force microscopy and conductive atomic force microscopy were used to directly probe the electrical properties of the films with spatial resolution along the thickness of the growth. The experimental profiles of the built-in electric fields and the spreading current found in the graded layers are shown to be consistent with simulations of the field distribution as well as of the electron and hole densities. Finally, it was directly observed that for gradients less than 0.28%Al/nm the native n-type donors still limit polarization-induced hole doping, making p-type conductivity still a challenge due to background impurities and defects.

11.
Inorg Chem ; 55(20): 10547-10557, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27690398

RESUMO

Density functional theory (DFT) calculations within the concept of the MBJ+U+SO (modified Becke-Johnson potential + U + spin orbit) approach were performed for a Tl4HgBr6 single crystal for the first time assuming weak noncentrosymmetry (space group P4nc). Excellent agreement was achieved between the calculated and experimental band-gap-energy magnitudes as well as the density of electronic states measured by the X-ray photoelectron spectroscopy method. It is a very principal result because usually the DFT calculations underestimate the energy-gap values. In the present study, we carry out calculations of the optical properties (absorption coefficient, real and imaginary parts of the dielectric function, electron energy-loss spectrum, refractive index, extinction coefficient, and optical reflectivity dispersions). It has been established that the principal origin of the observed weak acentricity is determined by delocalized band states at the top of the valence band originating from the p states of the Br atoms.

12.
Nanoscale Res Lett ; 11(1): 252, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27184965

RESUMO

Superlattices (SLs) consisting of symmetric layers of GaN and AlN have been investigated. Detailed X-ray diffraction and reflectivity measurements demonstrate that the relaxation of built-up strain in the films generally increases with an increasing number of repetitions; however, an apparent relaxation for subcritical thickness SLs is explained through the accumulation of Nagai tilt at each interface of the SL. Additional atomic force microscopy measurements reveal surface pit densities which appear to correlate with the amount of residual strain in the films along with the appearance of cracks for SLs which have exceeded the critical thickness for plastic relaxation. These results indicate a total SL thickness beyond which growth may be limited for the formation of high-quality coherent crystal structures; however, they may indicate a growth window for the reduction of threading dislocations by controlled relaxation of the epilayers.

13.
ACS Appl Mater Interfaces ; 7(41): 23320-7, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26431166

RESUMO

We report on AlxGa1-xN heterostructures resulting from the coherent growth of a positive then a negative gradient of the Al concentration on a [0001]-oriented GaN substrate. These polarization-doped p-n junction structures were characterized at the nanoscale by a combination of averaging as well as depth-resolved experimental techniques including: cross-sectional transmission electron microscopy, high-resolution X-ray diffraction, Rutherford backscattering spectrometry, and scanning probe microscopy. We observed that a small miscut in the substrate orientation along with the accumulated strain during growth led to a change in the mosaic structure of the AlxGa1-xN film, resulting in the formation of macrosteps on the surface. Moreover, we found a lateral modulation of charge carriers on the surface which were directly correlated with these steps. Finally, using nanoscale probes of the charge density in cross sections of the samples, we have directly measured, semiquantitatively, both n- and p-type polarization doping resulting from the gradient concentration of the AlxGa1-xN layers.

14.
EPMA J ; 6(1): 12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26097523

RESUMO

BACKGROUND: Male infertility has largely idiopathic, multifactorial origin. Oxidative stress is a major factor that affects spermatogenesis, in particular in aging. Cerium dioxide nanoparticles (CNPs) due to their antioxidative properties are promising to impact on the development of male infertility. The aims of this study were to investigate the effects of CNPs on fertility parameters in 24-month male rats and to overview relevant literature in the field of personalized treatments, predictive diagnosis, and preventive measures for male health and fertility. METHODS: We included 30 24-month-old male rats. After a week of adaptation to the standard diet, the rats were randomly divided into three groups with ten rats in each. Group 1 (controls) received only a standard diet. The rats of group 2 and 3 in adjunct to the standard diet during 10 days received intragastrically 10 % sodium citrate and citrate-coated CNPs in dose 1 mg/kg, respectively. We assessed sex hormones, epididymal sperm parameters and spermatogenesis, ultrasound, and morphological data of rat reproductive organs. RESULTS: After a 10-day administration of CNPs, we revealed significant decrease of lipid peroxidation product levels in serum and increase of catalase and SOD activity, associated with increase of sperm count (p < 0.001) and improvement in quantitative sperm parameters (motility, viability, and percentage of spermatozoa). We found no significant changes between sperm quantitative parameters in citrate-treated rats and controls and observed age-related decrease of activated Leydig cell number and focal atrophy of the seminiferous tubules. In CNP group, we observed regeneration of seminiferous tubules, increase number and activation of Leydig cells, and 2.5-fold significant increase of serum testosterone. Ultrasound data showed the slight increase of linear measurement and volume of rat testes in CNP group. Review highlights the benefits for predictive diagnosis, preventive measures, and personalized approaches to manage male infertility in the general concept of male health also related to aging. CONCLUSION: Citrate-coated 2-5-nm CNPs lead to increase in sex hormones levels, sperm count, and quality, as well as the activation of spermatogenesis in 24-month-old male rats. Nanoceria demonstrated the perspectives to be an effective infertility treatment via reduction of oxidative stress in male reproductive organs, in particular in aging.

15.
EPMA J ; 6(1): 13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26110044

RESUMO

BACKGROUND: Probiotics have great potential to contribute to development of healthy dietary regimes, preventive care, and an integrated approach to immunity-related disease management. The bacterial wall is a dynamic entity, depending on many components and playing an essential role in modulating immune response. The impact of cell wall elasticity on the beneficial effects of probiotic strains has not been sufficiently studied. The aim was to investigate the effect of lactic acid bacteria (LAB) and bifidobacteria strains on phagocytic system cells (macrophages) as related to bacterial wall elasticity, estimated using atomic force microscopy (AFM). METHODS: We conducted studies on Balb/c line mice 18-20 g in weight using lyophilized strains of LAB-Lactobacillus acidophilus IMV B-7279, Lactobacillus casei IMV B-7280, Lactobacillus delbrueckii subsp. bulgaricus IMV B-7281, and bifidobacteria-Bifidobacterium animalis VKL and Bifidobacterium animalis VKB. We cultivated the macrophages obtained from the peritoneal cavity of mice individually with the strains of LAB and bifidobacteria and evaluated their effect on macrophages, oxygen-dependent bactericidal activity, nitric oxide production, and immunoregulatory cytokines. We used AFM scanning to estimate bacterial cell wall elasticity. RESULTS: All strains had a stimulating effect on the functional activity of macrophages and ability to produce NO/NO2 in vitro. Lactobacilli strains increased the production of IL-12 and IFN-γ in vitro. The AFM demonstrated different cell wall elasticity levels in various strains of LAB and bifidobacteria. The rigidity of the cell walls among lactobacilli was distributed as follows: Lactobacillus acidophilus IMV B-7279 > Lactobacillus casei IMV B-7280 > Lactobacillus delbrueckii subsp. bulgaricus IMV B-7281; among the strains of bifidobacteria: B. animalis VKB > B. animalis VKL. Probiotic strain survival in the macrophages depended on the bacterial cell wall elasticity and on the time of their joint cultivation. CONCLUSION: LAB and bifidobacteria strains stimulate immune-modulatory cytokines and active oxygen and nitrogen oxide compound production in macrophages. Strains with a more elastic cell wall according to AFM data demonstrated higher resistance to intracellular digestion in macrophages and higher level of their activation. AFM might be considered as a fast and accurate method to assess parameters of probiotic strain cell wall to predict their immune-modulatory properties.

16.
Opt Express ; 18(1): 43-8, 2010 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-20173820

RESUMO

Here we report the first (as far as we know) experimental observation of extremely high enhancement factor due to elastic surface plasmon-polariton scattering by surface singularities.We have observed strong diffraction of surface plasmon-polaritons by shallow diffraction grating while its illumination by evanescent or volume waves do not shows any traces of diffraction structure in space distribution of scattered light.


Assuntos
Iluminação/métodos , Modelos Teóricos , Refratometria/métodos , Ressonância de Plasmônio de Superfície/métodos , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade , Propriedades de Superfície
17.
Carbohydr Res ; 333(2): 129-36, 2001 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-11448673

RESUMO

In the present work, we aimed at developing a chemoenzymatic procedure for the synthesis of beta-maltooligosaccharide glycosides. The primer in the enzymatic reaction was 2-chloro-4-nitrophenyl beta-maltoheptaoside (G(7)-CNP), synthesised from beta-cyclodextrin using a convenient chemical method. CNP-maltooligosaccharides of longer chain length, in the range of DP 8-11, were obtained by a transglycosylation reaction using alpha-D-glucopyranosyl-phosphate (G-1-P) as a donor. Detailed enzymological studies revealed that the conversion of G(7)-CNP catalysed by rabbit skeletal muscle glycogen phosphorylase b (EC 2.4.1.1) could be controlled by acarbose and was highly dependent on the conditions of transglycosylation. More than 90% conversion of G(7)-CNP was achieved through a 10:1 donor-acceptor ratio. Tranglycosylation at 37 degrees C for 30 min with 10 U enzyme resulted in G(8-->12)-CNP oligomers in the ratio of 22.8, 26.6, 23.2, 16.5, and 6.8%, respectively. The reaction pattern was investigated using an HPLC system. The preparative scale isolation of G(8-->11)-CNP glycosides was achieved on a semipreparative HPLC column. The productivity of the synthesis was improved by yields up to 70-75%. The structures of the oligomers were confirmed by their chromatographic behaviours and MALDI-TOF MS data.


Assuntos
Glucosídeos/síntese química , Glicogênio Fosforilase/metabolismo , Glicosídeos/síntese química , Oligossacarídeos/síntese química , Acarbose/química , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Glucosídeos/química , Glicogênio Fosforilase/química , Glicosídeos/química , Dados de Sequência Molecular , Estrutura Molecular , Oligossacarídeos/química , Coelhos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura
19.
Arzneimittelforschung ; 49(9): 779-90, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10514907

RESUMO

This report describes the development and the biology of Sch 55700, a humanized monoclonal antibody to human IL-5 (hIL-5). Sch 55700 was synthesized using CDR (complementarity determining regions) grafting technology by incorporating the antigen recognition sites for hIL-5 onto consensus regions of a human IgG4 framework. In vitro, Sch 55700 displays high affinity (Kd = 20 pmol/l) binding to hIL-5, inhibits the binding of hIL-5 to Ba/F3 cells (IC50 = 0.5 nmol/l) and blocks IL-5 mediated proliferation of human erythroleukemic TF-1 cells. In allergic mice, Sch 55700 (0.1-10 mg/kg, i.p. or i.m.) inhibits the influx of eosinophils in the lungs, demonstrates long duration of activity and the anti-inflammatory activity of this compound is additive with oral prednisolone. In allergic guinea pigs, Sch 55700 (0.03-30 mg/kg i.p.) inhibits both the pulmonary eosinophilia and airway hyperresponsiveness and at 30 mg/kg, i.p. inhibited allergic, but not histamine-induced bronchoconstriction. In allergic rabbits, Sch 55700 blocks cutaneous eosinophilia. Sch 55700 (0.1-1 mg/kg i.p.) also blocks the pulmonary eosinophilia and neutrophilia caused by tracheal injection of hIL-5 in guinea pigs. In allergic cynomolgus monkeys, a single dose of Sch 55700 (0.3 mg/kg i.v.) blocks the pulmonary eosinophilia caused by antigen challenge for up to six months. Sch 55700 is, therefore, a potent antibody against IL-5 in vitro and in a variety of species in vivo that could be used to establish the role of IL-5 in human eosinophilic diseases such as asthma.


Assuntos
Anticorpos Monoclonais/farmacologia , Hiper-Reatividade Brônquica/patologia , Eosinófilos/efeitos dos fármacos , Interleucina-5/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Ligação Competitiva , Hiper-Reatividade Brônquica/imunologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Clonagem Molecular , Eosinofilia/imunologia , Eosinofilia/patologia , Eosinófilos/imunologia , Eosinófilos/patologia , Humanos , Imunoglobulina G/imunologia , Interleucina-5/metabolismo , Cinética , Contagem de Leucócitos , Pulmão/imunologia , Pulmão/patologia , Macaca fascicularis , Camundongos , Camundongos Endogâmicos , Neutrófilos/patologia , Coelhos , Ratos , Pele/imunologia , Pele/patologia
20.
J Chromatogr B Biomed Sci Appl ; 718(1): 187-92, 1998 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9832375

RESUMO

Porous carbonaceous adsorbent was prepared by carbonization of saccharose in silica gel pores followed by leeching out of the silica matrix. The product of pyrolysis was then deactivated by hydrogenation. The resulting adsorbent shows intermediate sorption properties between those of the highly polar pyrolytic glassy carbon and the hydrophobic graphitized carbon. The microparticulate mesoporous carbon was examined for its use in capillary HPLC separations. The separation of selected stereoisomers in a 320 microm I.D. capillary column packed with the porous carbon particles is described and discussed. Additionally, the porous carbon filled with dextran gel was tested as a material for direct HPLC analysis of drugs in human serum.


Assuntos
Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Adsorção , Líquidos Corporais/química , Dextranos , Humanos , Indicadores e Reagentes , Cetoprofeno/sangue , Estereoisomerismo
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