bluuebunny/crossref_metadata_2025 huggingface dataset:
Flow cytometric cell‐cycle analysis of cultured fibroblasts from the giant panda, Ailuropoda melanoleuca L.
Authors: Han Zhi‐Ming , Chen Da‐Yuan , Li Jin‐Song , Sun Qing‐Yuan , Wang Peng‐Yan , Du Jun , Zhang He‐Min
Published: April 2003

In animal cloning, it is generally believed that the inactive diploid G0or G1stage of the cell cycle is beneficial to initiate cell‐cycle coordination and reprogramming following transfer of the donor nucleus. Previous experiments have demonstrated that serum starvation results in quiescent cell stage. Some experiments show that the majority of cells in a fully confluent cell culture are also in an inactive G1stage.

In order to provide more G0/G1stage cells for giant panda cloning, we carried out a flow cytometric analysis of the cell cycle of fibroblasts from the abdominal muscle of a giant panda at different passage numbers under different growth conditions, and after different periods of serum starvation. The percentage of G0+G1stage cells differed significantly under different growth conditions. Serum starvation effectively increased the percentage of G0+G1stage cells, and the cell cycle characteristics following serum starvation for varying periods of time differed with this and the initial confluency of the cultures. The data should help in choosing the optimal stage for preparing donor cells as well as increasing the potential cloning efficiency in our study of giant panda cloning.
Reproducibility of the measurement of the muscle ergoreflex activity in chronic heart failure
Authors: Scott Adam C. , Francis Darrel P. , Coats Andrew J.S. , Piepoli Massimo F.
Published: April 2003

Background:

A causative role for symptom generation in heart failure has been attributed to overactive muscle afferents, metaboreflex and mechanoreflex. We examined the reproducibility of the methods commonly used to assess these reflexes.

Material and methods:

Twelve stable heart failure patients (62.8±2.4 years) and 18 normals were studied. The metaboreflex was evaluated on both leg and arm exercises, by performing two runs of 5‐min submaximal handgrip and leg exercises. On one run the subjects recovered normally (control recovery), while on the other a post‐exercise regional circulatory occlusion (PE‐RCO) was induced in the exercising limb, to isolate the stimulation of the metaboreceptor after exercise. The metaboreflex was quantified as the difference in ventilation between the PE‐RCO and the control recovery periods with respect to rest. The existence of a mechanoreflex was sought by comparing the ventilatory increment per unit of active work (dVE/dVO2 ratio) between leg passive movement and active low level exercise. The coefficients of variation (CV) were computed to express the reproducibility of these reflexes in heart failure. Results: The metaboreflex was overactive in patients vs. normals during both arm (7.2±2.8 l/min vs. 0.06±0.3 l/min) and leg (5.6±1.2 l/min vs. 0.5±0.2 l/min) tests. The mechanoreflex was not different between patients and normals: dVE/dVO2 during passive movement 48.9±18.3 and 22.4±26.5; active exercise 42.3±18.4 and 31.9±18.7 (P=NS). In patients, the CV for the metaboreflex was 23.4% in the arm and 35.3% in the leg, while for the mechanoreflex test CV was 38.1% during passive movement and 21.1% during active exercise.

Conclusion:

The described method of measuring the muscle reflex activity shows an adequate reproducibility in heart failure patients.
Embodied Knowledge and Making Sense of Prenatal Diagnosis
Authors: Lippman Abby
Published: April 2003

Open‐ended, qualitative interviews with women to whom amniocentesis was offered were analyzed to understand how women made sense of these tests. We found that women, whether tested or not, negotiated with biomedical information. They transformed it through identifiable processes, then wove it with their own instincts and beliefs and with their personal experiences, thereby creating “embodied” knowledge on which their decisions were based. Women who were and were not tested may have differed from each other when categorized on the basis of a final, binary choice, but they were more alike than unalike in reaching this point. The apparent importance of embodied knowledge suggests the critical role of the listening activities of the genetic counselor and of awareness of the validity and importance of women's complementary ways of knowing and doing in understanding the uses and meanings of prenatal genetic testing.
The osteodystrophy of mucolipidosis type III and the effects of intravenous pamidronate treatment
Authors: Robinson C. , Baker N. , Noble J. , King A. , David G. , Sillence D. , Hofman P. , Cundy T.
Published: April 2003

Summary: Mucolipidosis type III (ML III; McKusick 252600) is a rare lysosomal storage disease in which skeletal involvement is prominent, in particular the destruction of vertebral bodies and the femoral heads. We describe studies in two siblings with ML III that suggest the presence of a distinct metabolic bone disorder. Biochemical indices of bone turnover were increased, and transiliac bone biopsy demonstrated both trabecular osteopenia and marked subperiosteal bone resorption. Intravenous pamidronate treatment given monthly for a year was well tolerated and produced dramatic clinical effects, with reduction in bone pain and improvements in mobility, despite incomplete suppression of bone resorption as assessed by biochemical, radiographic and histological criteria. Bisphosphonate therapy may have an important role in the management of bone pain in ML III, as it does in the related lysosomal disorder of Gaucher disease.
Client Perceptions of the Impact of Genetic Counseling: An Exploratory Study
Authors: Veach Patricia McCarthy , Truesdell Sarah E. , LeRoy Bonnie S. , Bartels Dianne M.
Published: April 2003

Twenty‐eight former genetic counseling clients seen at a major Midwestern university were recruited to be interviewed about their genetic counseling experiences, including most and least helpful aspects, what they learned, how this information impacted their decision‐making, and their perceptions of their genetic counselors' behaviors. Responses were inductively analyzed, and several themes were identified, including: Clients sought genetic counseling to obtain genetic‐medical information; a majority accurately recalled this information; genetic counseling influenced decisions for about 50% of the sample; decision‐making was affected by several extra‐session factors; a majority experienced distress during the session; most perceived genetic counselor responses as nondirective and liked this approach; counselor behaviors regarded as directive involved discussion of pregnancy termination; participants disagreed about the need for and provision of genetic counselor support; most regarded the session as helpful and stated that they would seek genetic counseling again. Suggestions for addressing these issues in practice and research are given.
Psychological Aspects of Genetic Counseling: XIII. Empathy and Decency
Authors: Kessler Seymour
Published: April 2003

The issues confronting genetic counselees, the demands of the “new genetics” and other factors suggest strongly the need for greater attention to counseling procedures which convey understanding of clients and help them feel more hopeful and more capable of dealing with their life problems. This should include interventions to help them feel more effective in their coping efforts as well as such ego‐bolstering techniques as the expression of kindness, the provision of appropriate rewards, and other attempts to raise the client's self‐esteem. These attempts should be a standard part of all genetic counseling. The traditional arguments of potential harm and time limitations often used to avoid counseling efforts are viewed through the lens of countertransference.
Case Report—Loyalty, Legacy, and Ledger: Contextual Therapy in a Patient with a Family History of Ovarian Cancer
Authors: Brown Tamsen Caruso , Garber Judy , Muto Michael , Schneider Katherine A.
Published: April 2003

A client's emotional experiences and reactions to those experiences are influenced by his/her family of origin and direct or indirect interactions with various family members. Contextual therapists propose that a client's satisfaction with a relationship depends on the equity of his/her emotional interactions with family members. When relationships are inequitable, trust between individuals disintegrates. In order to reestablish trust in a relationship, a balance of interests must be restored. If not, imbalances may be passed down to future generations. A case of a woman with a family history of ovarian cancer is reviewed with the principles of contextual therapy in mind. In her family, several legacies have resulted in unbalanced relationships between family members that lead to difficulty in establishing trust within the genetic counseling session.
Genetic Testing Considerations in Breast Cancer Patients
Authors: France Liz , Gray Jonathon , Elwyn Glyn , Tischkowitz Mark , Brain Kate , Sampson Julian , Anglim Cathy , Clarke Angus , Parsons Evelyn , Sweetland Helen , Mansel Robert , Barrett‐Lee Peter , Harper Peter
Published: April 2003

Genetic testing is now feasible for a growing number of cancers. Although the implications for unaffected relatives have been widely described, the impact of the tests on affected individuals are often not recognized. We present and discuss four cases that highlight some of the issues—for example, feelings of guilt and anxiety, intrafamilial conflict, and support needs—that may arise in testing affected individuals. We offer some suggestions to aid in the approach to such testing.
Understanding, Resisting, and Overcoming Oppression: Toward Psychopolitical Validity
Authors: Prilleltensky Isaac
Published: April 2003

My first objective in this paper is to synthesize, synoptically, the literature on oppression and liberation with the contributions to this special issue. To fulfil this aim I introduce a framework for understanding, resisting, and overcoming oppression. The framework consists of psychopolitical well‐being; experiences, consequences, and sources of oppression; and actions toward liberation. Each of these components is subdivided into 3 domains of oppression and well‐being: collective, relational, and personal. Experiences of suffering as well as resistance and agency are part of the framework. My second objective is to offer ways of closing the gap between research and action on oppression and liberation. To do so I suggest 2 types of psychopolitical validity: epistemic and transformative.
Narrating Survival and Change in Guatemala and South Africa: The Politics of Representation and a Liberatory Community Psychology
Authors: Lykes M. Brinton , Blanche Martin Terre , Hamber Brandon
Published: April 2003

Peace accords and international interventions have contributed to the suspension of armed conflict and the censuring of repressive regimes in many parts of the world. Some governments and their opposition parties have agreed to the establishment of commissions or other bodies designed to create historical records of the violations of human rights and foster conditions that facilitate reparatory and reconciliatory processes. This paper explores selected roles that community psychologists have played in this process of remembering the past and constructing new identities towards creating a more just future. With reference to two community groups (in Guatemala and South Africa) we show how efforts to “speak out” about one's own experiences of political and military repression involve complex representational politics that go beyond the simple binary opposition of silencing versus giving voice. The Guatemalan group consisted of Mayan Ixil women who, together with the first author, used participatory action research and the PhotoVoice technique to produce a book about their past and present struggles. The South African group, working within the ambit of the Truth and Reconciliation Commission and in collaboration with the third author and others, explored ways of speaking about their roles in apartheid and post‐apartheid society. Although both these initiatives can be seen as moments in on‐going struggles to overcome externally‐imposed repressive practices that censor the voices of marginalized communities, they also serve to dispel overly romanticized notions of “univocal” communities now liberated to express themselves in an unmediated and unequivocal fashion. The paper discusses how each group of women instead entered into subtly nuanced relationships with community psychologists involving a continual interplay between the authenticity of their self‐representational accounts and the requirements of the discursive technologies into which they were being inducted and the material conditions within their sites of struggle. In both cases the group's agenda also evolved over time, so that what emerged was not so much a particular account of themselves, or even the development of a particular “voice” for speaking about themselves, but an unfolding process—for the groups and for the community psychologists who accompanied them—of becoming active players in the postmodern, mediated world of self‐representational politics and social struggle.
Comparative mammalian choline metabolism with emphasis on the high-yielding dairy cow
Authors: Pinotti L , Baldi A , Dell'Orto V
Published: April 2003

The present review examines the importance of choline in dairy cow nutrition. Choline is an essential nutrient for mammals when excess methionine and folate are not available in the diet. The requirement for choline can be met by dietary choline and by transmethylation reactions. Two types of functions for choline are known: functions of cholineper se; functions as a methyl donor. The two principal methyl donors in animal metabolism are betaine, a metabolite of choline, and S-adenosyl-methionine, a metabolite of methionine. Choline and methionine are interchangeable with regard to their methyl group-furnishing functions. In adult ruminants, choline is extensively degraded in the rumen; for this reason dietary choline contributes insignificantly to the choline body pool and methyl group metabolism is generally conservative with a relatively low rate of methyl catabolism and an elevated rate ofde novosynthesis of methyl groups via the tetrahydrofolate system. In dairy ruminants, the dietary availability of choline is still low, but the output of methylated compounds in milk is high, and precursors from the tetrahydrofolate pathway are limiting, especially at the onset of lactation. Therefore choline may be a limiting nutrient for milk production in high-yielding dairy cows.
Ligand-dependent Inhibition of CD1d-restricted NKT Cell Development in Mice Transgenic for the Activating Receptor Ly49D
Authors: Voyle Roger B. , Beermann Friedrich , Lees Rosemary K. , Schümann Jens , Zimmer Jacques , Held Werner , MacDonald H. Robson
Published: April 2003

In addition to their CD1d-restricted T cell receptor (TCR), natural killer T (NKT) cells express various receptors normally associated with NK cells thought to act, in part, as modulators of TCR signaling. Immunoreceptor-tyrosine activation (ITAM) and inhibition (ITIM) motifs associated with NK receptors may augment or attenuate perceived TCR signals respectively, potentially influencing NKT cell development and function. ITIM-containing Ly49 family receptors expressed by NKT cells are proposed to play a role in their development and function. We have produced mice transgenic for the ITAM-associated Ly49D and ITIM-containing Ly49A receptors and their common ligand H2-Dd to determine the importance of these signaling interplays in NKT cell development. Ly49D/H2-Dd transgenic mice had selectively and severely reduced numbers of thymic and peripheral NKT cells, whereas both ligand and Ly49D transgenics had normal numbers of NKT cells. CD1d tetramer staining revealed a blockade of NKT cell development at an early precursor stage. Coexpression of a Ly49A transgene partially rescued NKT cell development in Ly49D/H2-Dd transgenics, presumably due to attenuation of ITAM signaling. Thus, Ly49D-induced ITAM signaling is incompatible with the early development of cells expressing semi-invariant CD1d-restricted TCRs and appropriately harmonized ITIM–ITAM signaling is likely to play an important role in the developmental program of NKT cells.
DC-SIGN (CD209) Mediates Dengue Virus Infection of Human Dendritic Cells
Authors: Tassaneetrithep Boonrat , Burgess Timothy H. , Granelli-Piperno Angela , Trumpfheller Christine , Finke Jennifer , Sun Wellington , Eller Michael A. , Pattanapanyasat Kovit , Sarasombath Suttipant , Birx Deborah L. , Steinman Ralph M. , Schlesinger Sarah , Marovich Mary A.
Published: April 2003

Dengue virus is a single-stranded, enveloped RNA virus that productively infects human dendritic cells (DCs) primarily at the immature stage of their differentiation. We now find that all four serotypes of dengue use DC-SIGN (CD209), a C-type lectin, to infect dendritic cells. THP-1 cells become susceptible to dengue infection after transfection of DC-specific ICAM-3 grabbing nonintegrin (DC-SIGN), or its homologue L-SIGN, whereas the infection of dendritic cells is blocked by anti–DC-SIGN antibodies and not by antibodies to other molecules on these cells. Viruses produced by dendritic cells are infectious for DC-SIGN– and L-SIGN–bearing THP-1 cells and other permissive cell lines. Therefore, DC-SIGN may be considered as a new target for designing therapies that block dengue infection.
Analytic solution of partial differential equations with Adomian's decomposition
Authors: García‐Olivares Antonio
Published: April 2003

Adomian's method is completed to obtain the analytic solution of any partial differential equation with boundary conditions defined on the four sides of a rectangle. Adomian's decomposition method is first used to obtain the N‐order approximant to the one direction partial solution that satisfies the boundary conditions on that direction. Then the functions obtained are variationally modified on the four sides to make them compatible with a given experimental error. The product of these transformations is an analytic approximation to the solution which is compatible with both the weak norm imposed on the boundaries and the accuracy imposed in the whole domain.
Drug-Susceptible
Mycobacterium tuberculosis
Beijing Genotype Does Not Develop Mutation-Conferred Resistance to Rifampin at an Elevated Rate
Authors: Werngren Jim , Hoffner Sven E.
Published: April 2003

The
Mycobacterium tuberculosis
Beijing genotype has drawn attention because it is often strongly associated with multidrug-resistant tuberculosis (MDR-TB). A possible reason is that the Beijing strains may have an enhanced capacity to develop drug resistance. In this study, we used the Luria-Delbrück fluctuation test to investigate whether strains of Beijing and non-Beijing genotypes exhibit differences in the acquisition of drug resistance. The
M
.
tuberculosis
reference strain H37Rv and 12 fully drug-susceptible clinical isolates, 6 of which were of the Beijing genotype, were examined. To determine the distribution of rifampin-resistant mutants, 25 independent cultures were made for each strain. The average mutation frequencies for the non-Beijing (H37Rv included) and Beijing genotypes were estimated to be 4.4 × 10
−8
and 3.6 × 10
−8
, respectively. The corresponding average mutation rates for the non-Beijing and Beijing strains were 1.3 × 10
−8
and 1.1× 10
−8
mutations per cell division, respectively. The results suggest that the association of the Beijing genotype with MDR-TB is not due to an altered ability to develop resistance.
Performance Characteristics of the TRUGENEHIV-1Genotyping Kit and the Opengene DNA Sequencing System
Authors: Kuritzkes Daniel R. , Grant Robert M. , Feorino Paul , Griswold Marshal , Hoover Marie , Young Russell , Day Stephen , Lloyd, Robert M. , Reid Caroline , Morgan Gillian F. , Winslow Dean L.
Published: April 2003

The TRUGENEHIV-1Genotyping Kit and OpenGene DNA Sequencing System are designed to sequence the protease (PR)- and reverse transcriptase (RT)-coding regions of human immunodeficiency virus type 1 (HIV-1)pol. Studies were undertaken to determine the accuracy of this assay system in detecting resistance-associated mutations and to determine the effects of RNA extraction methods, anticoagulants, specimen handling, and potentially interfering substances. Samples were plasma obtained from HIV-infected subjects or seronegative plasma to which viruses derived from wild-type and mutant infectious molecular clones (IMC) of HIV-1 were added. Extraction methods tested included standard and UltraSensitive AMPLICOR HIV-1 MONITOR, QIAGEN viral RNA extraction mini kit, and QIAGEN Ultra HIV extraction kit, and NASBA manual HIV-1 quantitative NucliSens. Sequence data from test sites were compared to a “gold standard” reference sequence to determine the percent agreement. Comparisons between test and reference sequences at the nucleotide level showed 97.5 to 100% agreement. Similar results were obtained regardless of extraction method, regardless of use of EDTA or acid citrate dextrose as anticoagulant, and despite the presence of triglycerides, bilirubin, hemoglobin, antiretroviral drugs, HIV-2, hepatitis C virus (HCV), HBV, cytomegalovirus, human T-cell leukemia virus type 1 (HTLV-1), or HTLV-2. Samples with HIV-1 RNA titers of ≥1,000 copies/ml gave consistent results. The TRUGENEHIV-1Genotyping Kit and OpenGene DNA Sequencing System consistently generate highly accurate sequence data when tested with IMC-derived HIV and patient samples.
In Vitro Susceptibility Testing of Four Antibiotics against
Borrelia burgdorferi
: a Comparison of Results for the Three Genospecies
Borrelia afzelii
,
Borrelia garinii
, and
Borrelia burgdorferi
Sensu Stricto
Authors: Sicklinger Martin , Wienecke Ralf , Neubert Uwe
Published: April 2003

MICs and minimal bactericidal concentrations (MBCs) were evaluated for the four antibiotics azithromycin, amoxicillin, ceftriaxone, and doxycycline against the three main genospecies of
Borrelia burgdorferi
sensu lato. In MBC testing, statistically significant differences between the genospecies could be found in 7 out of 12 comparative evaluations (
P
< 0.05).
Mycetoma of the Foot Caused byFusarium solani: Identification of the Etiologic Agent by DNA Sequencing
Authors: Yera H. , Bougnoux M. E. , Jeanrot C. , Baixench M. T. , De Pinieux G. , Dupouy-Camet J.
Published: April 2003

We report a case ofFusarium solanimycetoma of the foot that could not be diagnosed by culture, but was correctly identified after amplification and sequence analysis of fungal internal transcribed spacers 1 and 2 and 5.8S ribosomal DNA regions.
Adsorption of 2-Thiouracil at the Mercury/Electrolyte Interface II. Capacitance Transients
Authors: Wandlowski Thomas , Levie Robert de
Published: April 2003

The adsorption of 2-thiouracil at the mercury-water interface exhibits several regions. In region I, the capacitance is consistently higher than that of the supporting electrolyte, as is usually observed for sulfur-containing compounds. At higher concentrations of 2-thiouracil, two additional adsorption regions appear. Region II corresponds to a condensed monolayer, formed by nucleation and two-dimensional growth, while region III exhibits behavior typical for polylayer formation.
Study of Sedimentation Velocity of Block Copolymer Micelles
Authors: Tian Minmin , Ramireddy C. , Webber Stephen E. , Munk Petr
Published: April 2003

No anomalies were observed during the measurement of sedimentation coefficients of block copolymer micelles formed by copolymers of styrene and methacrylic acid in a mixed solvent; 80 vol.% of dioxane and 20 vol.% of water. The shapes of the sedimenting boundaries suggest that the size heterogeneity of the micelles is small. Linear relations between 1/s and c were obtained. The value of the hydrodynamic coefficient κ was between 2 and 4 in a good agreement with the value 2.75 or 2.86 that was obtained by combining Burgers' or Fixman's values of the coefficient of the concentration dependence kvs for hard spheres with Einstein's value of [η] for spheres.
[n]Staffanes with Terminal Nitrile and Isonitrile Functionalities and Their Metal Complexes
Authors: Janecki Tomasz , Shi Shu , Kaszynski Piotr , Michl Josef
Published: April 2003

The synthesis of several bridgehead nitrile and isonitrile derivatives of the first two [n]staffanes, n = 1 and 2, is reported. Both isonitriles were converted into pentacarbonylmolybdenum complexes. [2]Staffane-3-carbonitrile was converted to a complex with rhodium(II) acetate, which was characterized by a single crystal X-ray analysis.
Laser-Induced Decomposition of Heptafluoro-2-Iodopropane
Authors: Pola Josef , Horák Milan
Published: April 2003

CO2 laser-induced homogeneous decomposition of i-C3F7I yields a variety of perfluorinated compounds, which are suggested to be formed by recombinations of carbenes and radicals generated upon the cleavage of the C-I bond and the fragmentation of the i-C3F7. radical. The decomposition of i-C3F7I in the presence of ethene leads mainly to the formation of (i-3F7CH2)2 and i-C3F7(CH2)2I.
Electronic Nature of α-Methoxy, Amino, Cyano, and Mercapto Nitrones
Authors: Gallis David E. , Warshaw James A. , Acken Bruce J. , Crist DeLanson R.
Published: April 2003

The electronic nature of various C-substituted nitrones was investigated by IR spectroscopy and 13C NMR as well as MNDO calculations. These include α-methoxy nitrones (imidate N-oxides) RC(OMe)=N(O)t-Bu with R = p-MeOC6H4 (Ia), C6H5 (Ib), p-NO2C6H4 (Ic), and H (Id) and nitrones YCH=N(O)t-Bu with Y = CN (IIIa), n-BuS (IIIb), C6H5CH2NH (IIIc). Upfield 13C shifts of C(α), the iminyl (C=N) carbon, of imidate N-oxides I versus the corresponding imidates are less than the usual upfield shifts of imine N-oxides versus imines, suggesting less buildup of electron density on C(α) in the case of alcoxy nitrones. Charge density and π bond order values from MNDO calculations for C-methoxy-C-phenyl nitrones versus model systems confirm this result and indicate a more localized C=N π bond in nitrones bearing an α-methoxy group. For N-tert-butyl nitrones with an α heteroatom (nitrogen or sulfur), phenyl, or cyano group, C(α) shifts move downfield for π-donating groups and upfield for π-accepting groups. This "reverse substituent effect" as well as C=N stretching frequencies can also be readily explained by C=N π bond containment by lone pair groups. The reported enhanced cycloaddition reactivity of α-alkoxy nitrones and their electrochemical behavior are discussed in terms of HOMO energy levels.
Antituberculotic 4'-Cyclohexylthiobenzanilides: Combination of Free-Wilson Method in QSAR with Topliss Approach
Authors: Waisser Karel , Kubicová Lenka , Odlerová Želmíra
Published: April 2003

On the basis of a preliminary study of antimycobacterial activity of thiobenzanilides against Mycobacterium kansasii, a group of 4'-cyclohexylthiobenzanilids have been prepared which exhibit a significant activity against the microorganism mentioned. The whole set of 35 thiobenzanilides was tested with Mycobacterium tuberculosis, and on the basis of QSAR analysis conclusions have been made with regard to prognostics of structures suitable for further studies. The problem was solved by the method by Free and Wilson combined with the Topliss approach and by a Hansch type analysis.
Determination of Diffusion Coefficient of Carbon Dioxide in Polyethylene by the Method of Moments
Authors: Jirásek Jan , Šípek Milan
Published: April 2003

By using the method of moments, the values of diffusion coefficients of carbon dioxide in high-pressure polyethylene of two different thicknesses were determined at 25 °C. The values of diffusion coefficients determined with the accuracy of about ±3% are in good agreement both with the values obtained by the optimization method, and with the published values determined on the basis of asymptotic solutions of diffusion equations.
The Effects of 1-Propanol on Behaviour of Human Serum Albumin in Alkaline Solution
Authors: Karpenko Vladimír , Škrabana Rostislav
Published: April 2003

The effects of 1-propanol ant to a certain extent of ethanol on human serum albumin were studied over the pH range 7 - 13.3 and alcohol concentrations up to 20 vol.%. In some case behaviour of the native preparation was compared with albumin cleared of weaker bound fatty acids. The data obtained by UV-spectrophotometry were discussed from the point of view of individual types of chromophores as well as in a broader context of the secondary structure. The results can be summarized as follows: (a) Partial removal of bound fatty acids has an influence on the dissociation of tyrosines. (b) The effect of alcohols on this dissociation is rather complex, the permitivity of the solvent being only a part of it. (c) At high alkaline pH a series of peaks in the fourth-derivative absorption spectra appear in the region 305 - 320 nm. These peaks were shown to correspond to buried dissociated tyrosines. (d) In the presence of 1-propanol a small conformational transition of albumin molecule is observed at pH below 9.
Investigation of the Conditions of Extraction of Ion-Associates of 3-Quinuclidinyl Benzilate with Acidic Dyes
Authors: Halámek Emil , Kobliha Zbyněk
Published: April 2003

Ion-associates of 3-quinuclidinyl benzilate (BZ) with thirteen acidic dyes were examined after their extraction into chloroform. Based on spectrophotometric measurements, the optimum pH of the aqueous phase was established and the extraction yields, distribution ratios, conditional extraction constants and limits of detection were calculated. Bromocresol green and metanil yellow are suggested as reagents for the analysis of BZ.
The Effect of Scalling-Up and Hydrodynamic Properties of Stirring System on the Kinetics of Vegetable Oil Hydrogenation
Authors: Dědek Ivan
Published: April 2003

The stirring system of classical turbine agitator beside the anchor agitation system was studied from the point of view of the effect of their hydrodynamic properties on the kinetics of sunflower oil hydrogenation, It was found out that the anchor agitator makes up a higher gas hold-up than the turbine one and its efficiency from the view of reaction kinetics is higher. On changing the geometrical parameters of anchor agitator - by reducing its blade height - its hydrodynamic properties change considerably, and its efficiency decreases. The scaling-up of the stirring system did not manifest itself in the reaction rate in case of the turbine agitator. With the anchor agitator, the scaling-up resulted in the confirmation of its specific effect on the reaction kinetics, viz., on exceeding the limiting value of stirring frequency, the dramatic loss in efficiency took place.
Crystal and Molecular Structure of the s-fac-[Co((S)-Asp)(medien)]ClO4 . H2O . HClO4 Isomer
Authors: Ondráček Jan , Maixner Jaroslav , Ondráčková Jana , Jursík František
Published: April 2003

The crystal and molecular structure of s-fac-[Co((S)-Asp)(medien)]ClO4 . H2O . HClO4 was elucidated by the heavy atom method. The positional parameters of the nonhydrogen atoms and their anisotropic temperature parameters were refined based on 2 474 observed reflection with final values of R = 0.0603 and wR = 0.0616. The substance crystallized in the orthorhombic system in the space group P212121, Z = 4, a = 8.536(1), b = 13.378(1), c = 16.899(2) Å. The structure comprises layers of the complex cation which alternate with layers containing two perchlorate anions and one hydroxonium cation. The five-membered chelate ring of 4-methyl-1,4,7-triazaheptane exist in the asymmetric λ, δ envelope conformations and the N-CH3 group of the triamine has the exo orientation. The five-membered ring of (S)-aspartic acid assumes the symmetric envelope conformation, the six-membered chelate ring, the skew boat conformation.
Oxidizability and Structure of Lactams
Authors: Burda Jaroslav , Lánská Božena
Published: April 2003

The radical-initiated chain oxidation of five- to nine-membered lactams with molecular oxygen has been studied by the quantum-chemical method AM1. It has been confirmed that the reaction is controlled by its propagation step. The kinetic length of the oxidation chains correlates with the energy of formation of the lactam radical by abstraction of hydrogen from the methylene group adjacent to nitrogen atom. With five- to eight-membered rings the reaction is symmetry-forbidden.
Vibrational Spectra and Normal Coordinate Analysis of Disulfuryl Difluoride S2O5F2 and Diselenonyl Difluoride Se2O5F2
Authors: Toužín Jiří , Černík Miloš
Published: April 2003

Raman spectra (1 600 - 100 cm-1) of liquid S2O5F2 and Se2O5F2 and infrared spectra of liquid and gaseous S2O5F2 were measured. A modified general valence force field was used for their interpretation by normal coordinate analysis. Refinement of the number of lines in the Raman spectrum of S2O5F2 by means of numerical separation of the overlapping bands led to the conclusion that liquid S2O5F2 consists at least of three rotamers at room temperature.
Application of Magnesium Alkoxides to Syntheses of Benzoheterocyclic Compounds
Authors: Svoboda Jiří , Nič Miloslav , Paleček Jaroslav
Published: April 2003

The Dieckmann condensation of methyl [(2-methoxycarbonyl)phenyl]-X-acetates Ia-Ih (X = O, S, SO2, NH, NCH3) initiated by action of magnesium methoxide, ethoxide, isopropoxide and other basic reagents have been studied under various conditions. Whereas magnesium methoxide has comparable efficiency as sodium methoxide and potassium tert-butoxide in syntheses of benzoheterocyclic compounds IIa-IIh, magnesium ethoxide gives the ethyl ester IIb in medium yield, and magnesium isopropoxide is quite inefficient in the condensation reaction. The alkylation of the esters IIa, IId, and IIg with methyl chloroacetate in the presence of sodium hydride in dimethylformamide gives the diesters IIi - IIk which on action by potassium tert-butoxide undergo the cyclization reaction to give esters III.
Preparation of Unlabelled and [3H]-Labelled Epitestosterone and Its Metabolites
Authors: Kasal Alexander , Fuksová Květa , Pouzar Vladimír
Published: April 2003

Cold as well as [3H]-labelled substrates and metabolites IX - XI, XV, XVI, XX - XXII, XXIV, XXV and XXVIII were prepared by catalytic hydrogenation of epitestosterone (VIII) and ∆1-dehydroepitestosterone (XIII). The key step in the preparation of compound XXVIII was reaction of 3β-tosylates XXVI and XXX with potassium nitrite in dimethyl sulfoxide.
Synthesis of RIA Haptens: 3α,11α-Dihydroxy-5α-pregnan-20-one 11-Hemisuccinate
Authors: Kasal Alexander , Pásztorová Světlana
Published: April 2003

5α-Pregnane-3α,11α-diol-20-one (XVII) was prepared by hydroxylation of 5α-pregnan-3α-ol-20-one (XVI) by Rhizopus nigricans and by chemical conversion of 11α-hydroxyprogesterone (I). The diol XVII was partially acylated with 2-(trimethylsilyl)ethyl hydrogen succinate and the 11α-succinate XVIII was converted to the target 11α-hemisuccinate XXI.
Synthesis and Biological Effects of Acyclic Analogs of Deazapurine Nucleosides
Authors: Dvořáková Hana , Holý Antonín , Votruba Ivan , Masojídková Milena
Published: April 2003

Deaza analogs of three basic types of S-adenosyl-L-homocysteine hydrolase (SAHase) inhibitors, (S)-DHPA (I), eritadenine (II) and AHPA (III), were prepared. Alkylation of 3-deazaadenine (V), 3-deazapurine (VI), 1-deazaadenine (VII) and 4-amino-6-bromo-5-cyanopyrrolo[2,3-d]pyrimidine (XXII) with (R)-2,2-dimethyl-4-tosyloxymethyl-1,3-dioxolane (XIIIb), followed by acid hydrolysis, afforded the corresponding (S)-2,3-dihydroxypropyl derivatives XVIIa -XIXa and XXV. Reaction of V and VII with 2,3-O-cyclohexylidene-D-erythrono lactone (XXIX) and subsequent removal of the protecting groups in an acid medium gave eritadenine analogs XXVII and XXVIII. Compounds V and VII were alkylated with bromoacetaldehyde diethyl acetal to give N-(2,2-diethoxyethyl) derivatives XXXII and XXXIII from which the substituted acetaldehyde derivatives were liberated in situ and converted into compounds XXX and XXXI by cyanohydrine reaction followed by acid hydrolysis. The alkylations were performed in dimethylformamide with sodium or cesium salts of the bases. Biological activity was observed only with 3-deazaadenine derivatives XVIIa, XXVII and XXX, which exhibit both enzyme-inhibitory and antiviral activities.
Formation of Polyelectrolyte Complexes
Authors: Mikulík Jaroslav , Vinklárek Zdeněk , Vondruška Milan
Published: April 2003

Polyelectrolyte complexes are intermacromolecular complexes, i.e. macromolecular compounds formed by interpolymeric reaction between oppositely charged polyelectrolytes. The effect of the molecular parameters and reaction conditions on the formation and structure of polyelectrolyte complexes is reviewed.
Chemisorption of Oxygen on Supported Nickel Catalysts
Authors: Zahradníková Hana , Šolcová Olga , Jirátová Květa
Published: April 2003

One unsupported nickel catalysts (about 55 wt.% Ni) supported on SiO2, Al2O3, TiO2, Nb2O5, ZrO2, V2O5 and ZnO were characterized by pulse dynamic oxygen chemisorption measured at -78 °C and evaluated in the reaction of reductive amination of diethylene glycol. Correlation was obtained between their oxygen uptake and catalytic activity.
The Use of Amberlite IRA-410 for Preparation of Terminal Chlorodeoxy Sugars
Authors: Vukojevic Nada , Miljković Dušan , Popsavin Mirjana , Popsavin Velimir
Published: April 2003

Anion-exchange resin Amberlite IRA-410 was found to be an effective and selective reagent for the nucleophilic displacement of primary tosyloxy (mesyloxy) groups in 3,5-disulfonates of xylofuranose derivatives I and III, as well as in 3,5,6-trisulfontes and 3,6-ditosyl derivatives of glucofuranose V, VII and IX. In all examined cases only the primary sulfonyloxy groups were replaced with chloride anions, whereupon the corresponding terminal chlorodeoxy derivatives were obtained in good yields.
Synthesis and Structure-Activity Relationship of Scyliorhinin I Analogues Modified in Position 3, 6, 7 and 8
Authors: Zboinska Jolanta , Rolka Krzysztof , Kupryszewski Gotfryd , Golba Krzysztof , Imiolek Piotr , Janas Piotr , Herman Zbigniew S.
Published: April 2003

Seven analogues of scyliorhinin I modified in positions 3, 6, 7 and 8 were synthesized by the solid-phase method. Their agonistic activity was determined on isolated guinea pig ileum (GPI). Except for the two analogues modified in position 6, all exhibited dose-dependent activity. Analogues with Phe, D-Phe(F) in position 7 and Abu in position 8 appeared significantly more active than scyliorhinin I and substance P, whereas the analogue with NMeLeu in position 8 appeared to be twice as active as the native molecule, but displayed only 12% of the substance P activity. CD studies indicated that the analogues modified in position 8 behaved differently in the surroundings that mimics the biological membranes.
Synthesis of 2(3H)-Benzoxa(thia)zolones Containing a Heterocycle in the Alkyl Group at Position 3
Authors: Petrov Ognyan I. , Kalcheva Veneta B. , Antonova Antonina Ts.
Published: April 2003

The present paper deals with the synthesis of new compounds which combine two structures showing biological activities i. e. those of 3-alkylated 2(3H)-benzoxa(thia)zolones and 5-substituted tetrazoles or 1,3,4-oxadiazoles.
Reactions of Benzoylisothiocyanate with Acetoacetanilide: Synthesis of Pyrazole, Pyridine, Pyrimidine, Pyrazolo[3,4-d]pyrimidine, Pyrazolo[4,3-d]pyrimidine and Pyrido[4,3-d]oxazine Derivatives
Authors: Mohareb Rafat Milad , Aziz Suzan Ibrahim , Abdel-Sayed Nadia Iskander , El-Ablack Fawzia Zakeria
Published: April 2003

We describe in this article the results of investigations involving the reaction of benzoyl isothiocyanate I with acetoacetanilides IIa, IIb.
Spiroheterocyclic Systems: Part I: Synthesis of Some New Spiroheterocycles Related to 1-Oxa-4-thiaspiro[4,4]nonan-2-one and/or [4,5]Decan-2-one
Authors: El-Zohry Maher F. , Awad Ibrahim M. A. , Abdel-Hafez Ali A.
Published: April 2003

As continuation to our previous work, we report herein the synthesis of some new spirothiazolopyrazoles, spirothiazoloisoxazoles, spirothiazolopyrimidinones and spirothiazolothiopyrimidinones.
Effect of the Method of Synthesis, Forming, and Activation on the Catalytic Activity of Vanadium-Phosphorus Catalysts
Authors: Brutovský Milan , Ferdinandyová Lucia , Gerej Štefan , Novák Ján
Published: April 2003

Methods where vanadium in the precursor is reduced to V4+ in solution are well suited to the synthesis of vanadium-phosphorus catalyst because the high temperatures (500 to 800 °C) required to transform the precursor to the active catalyst are thus avoid, which is desirable from the chemical as well as structuro-physical aspects. The way of forming and activating the catalyst, i.e. the temperature regime of the treatment and the kind of the gas atmosphere, were found to affect appreciably the catalyst activity in the partial oxidation of butane to maleic anhydride.. Forming procedures resulting in sufficiently fine crystals and optimized lattice defects are suitable. The application of synthesis, forming and activation procedures exhibiting a low tendency to form, in the catalyst phase composition, condensed phosphates such as VO(PO3)2 or even V(PO3)3 is also beneficial to the catalyst activity. The catalytic properties of the vanadium-phosphorus catalyst which was prepared in concentrated HCl were improved considerably by doping the lattice with modifying metal cations.
Study on 50 MHz ICP Torch with Medium Resolution Spectrometer. Determination of Rare Earth Elements in Complicated Matrices
Authors: Kanický Viktor , Toman Jiří , Otruba Vítězslav , Sommer Lumír
Published: April 2003

ICP-OES is a suitable method for the determination of R.E.E. (rare earth elements),which exhibits advantages in the absence of interferences of evaporation, low detection limits and a great linear range of calibration graphs. A spectrometer having spectral bandwidth (SBW) 30 pm with 50 MHz ICP source were used. Optimum working conditions resulted from detailed studies of axial intensity distributions. Differences in axial intensity distribution were evident when compared with usual 27.12 MHz ICP sources. Matrix interferences of alkaline salts and acids have been evaluated and the optimum spectral lines selected respecting mutual spectral interferences of R.E.E.
Axial Dispersion in an Apparatus with Mobile Packing
Authors: Palatý Zdeněk
Published: April 2003

The paper deals with modelling of the flow of liquid on a plate with mobile packing. The results of measurements have been interpreted by means of a simple dispersion model whose two parameters were determined from the nonideal step-input of a tracer and its response. It has been found that in the gas flow rate region followed (1.0 - 3.5 m s-1), the liquid flow rate followed (5.36 - 12.5 . 10-3 m s-1), and the static bed height followed (21 - 47 . 10-3 m) the diffusion Peclet number is independent of these quantities. The mean residence time of the liquid on the plate decreases with increasing flow rate of Both gas and liquid, but it increases with the increasing height of packing.
Nonconventional Friedel-Crafts Chemistry. VIII. On the Preferentional Intramolecular Cyclization Reactions of 2-Aryl-2-benzyl-1,3-oxathiolan-5-one under Lewis Acids Catalytic Action
Authors: El-Zohry Maher F. , Hozien Zeinab A. , Mohamed Omima S.
Published: April 2003

In our previous work we reported the intermolecular reactions of spirothialactones with arenes, ferrocene and thiophene. The results of these investigation together with our interest in Friedel-Crafts chemistry prompted us to consider the intramolecular cyclization reactions of 2-aryl-2-benzyl-1,3-oxathiolan-5-one derivatives (IIa - IId) under Lewis acid catalyst effect.
Effect of Pressure Decrease on the Belousov-Zhabotinskii Oscillation Reaction
Authors: Ševčík Petr , Kolínková Lenka
Published: April 2003

The decrease of pressure from 101.3 kPa to 5.25 kPa has an effect on the parameters of Belousov-Zhabotinskii reaction in batch system in the atmosphere of N2, O2 and CO2. Under the anaerobic conditions, the difference in the form of the reduced phase of oscillatory cycle persists even at vigorous stirring. The role of nucleation, supersaturation, atmosphere, and rate of stirring in these effects is discussed.
Synthesis and Biological Effects of 9-(3-Hydroxy-2-phosphonomethoxypropyl) Derivatives of Deazapurine Bases
Authors: Dvořáková Hana , Holý Antonín , Alexander Petr
Published: April 2003

Analogs of antiviral 9-(S)-(3-hydroxy-2-phosphonomethoxypropyl)adenine (HPMPA, I), containing modified purine bases 3-deazaadenine XII, 1-deazaadenine XIV, 7-deaz-7-cyanoaadenine XXXII and 3-deazaguanine XXXVIII, were prepared by alkylation of the bases with synthon XVII, containing preformed structure of the side chain, in the presence of cesium carbonate. The obtained protected derivatives were deblocked successively with sodium methoxide and bromotrimethylsilane to give phosphonic acids XII, XIV, XXXII and XXXVIII. Compounds XII, XIV and XVI were also prepared from (S)- or (R)-9-(2,3-dihydroxypropylderivatives VI, VII and XV by the reaction with chloromethanephosphonyl dichloride, isomerization of the arising 2'- and 3'-chloromethanephosphonates and conversion of the 3'-isomers into the phosphonic acids in alkaline medium. The 3-deaza analog XII was also prepared by ditritylation of VI, reaction with bis(2-propyl) tosyloxymethanephosphonate (XXII), subsequent acid hydrolysis and reaction with bromotrimethylsilane. 3-DeazaHPMPA (XII) is a potent inhibitor of DNA viruses (HSV-1, HSV-2, VZV, CMV) and exhibits activity against Plasmodium sp.
Synthesis of Some New Bis[1-(2-aroyl-3-aryl)cyclopropylcarbonyl]benzenes and Pyridines under Phase Transfer Catalysis (PTC) Method
Authors: Bhaskar Reddy Dandu , Seenaiah Biradavolu , Padmaja Adivireddi , Ramana Reddy Pallela Venkata
Published: April 2003

Some new bis[1-(2-aroyl-3-aryl)cyclopropylcarbonyl]benzenes and pyridines IV - VI have been prepared by the cycloaddition of dimethylsulfonium phenacylide to 1,1'-(1,3-, 1,4-phenylene, and 2,6-pyridylene)-bis(3-aryl-2-propen-1-ones) I - III by adopting two different methods. The advantages of the PTC method over the other have been discussed. The structures of the compound have been confirmed by spectral data.
Nonisochoric Reactor with Constant Feed Rate of One Component
Authors: Dušek Václav , Skopal František
Published: April 2003

For a chemical reactor with constant volume feed rate equations have been derived which describe the time dependences of concentration of the reaction components, and their approximation has been suggested. The applicability of the approximation has been verified on a model redox system Ce(IV)/V(IV) in sulfuric acid medium.
Role of the Structure and Electronic Properties of Fe2O3-MoO3 Catalyst on the Dehydration of Isopropyl Alcohol
Authors: Said Abd El-Aziz A.
Published: April 2003

Molybdenum oxide catalyst doped or mixed with (1 - 50) mole % Fe3+ ions were prepared. The structure of the original samples and the samples calcined at 400 °C were characterized using DTA, X-ray diffraction and IR spectra. Measurements of the electrical conductivity of calcined samples with and without isopropyl alcohol revealed that the conductance increases on increasing the content of Fe3+ ions up to 50 mole %. The activation energies of charge carriers were determined in presence and absence of the alcohol. The catalytic dehydration of isopropyl alcohol was carried out at 250 °C using a flow system. The results obtained showed that the doped or mixed catalysts are active and selective towards propene formation. However, the catalyst containing 40 mole % Fe3+ ions exhibited the highest activity and selectivity. Correlations were attempted to the catalyst composition with their electronic and catalytic properties. Probable mechanism for the dehydration process is proposed in terms of surface active sites.
A Brief Synthesis of 3-Hydroxyeicos-4(E)-en-1-yne, a Component of Marine Sponge, Cribrochalina vasculum
Authors: Kulkarni Bhimashnkar A. , Chattopadhyay Angshuman , Mamdapur Vasant R.
Published: April 2003

A short approach to the synthesis of 3-hydroxyeicos-4(E)-en-1-yne from palmitic acid is described.